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The Status
and Trends Of the Global HIV/AIDS Pandemic
Official Satellite
Symposium July 5 - 6, 1996
Jointly organized
by
The AIDS
Control and Prenvention (AIDSCAP) Project of Family Health International
The François-Xavier
Bagnoud Center for Health and Human Rights of the Havard School
of Pubil Health
UNAIDS The
Joint United Nation Programme on HIV/AIDS
Introduction
The Status
and Trends of the Global HIV/AIDS Pandemic Satellite Symposium
of the XI International Conference on AIDS was jointly organized
by the AIDS Control and Prevention (AIDSCAP) Project of Family
Health International, the François-Xavier Bagnoud Center for Health
and Human Rights of the Harvard School of Public Health and the
Joint United Nations Programme on HIV/AIDS (UNAIDS). This two-day
Symposium, held on 5-6 July 1996 in Vancouver, Canada, resulted
from an extraordinary response to The Status and Trends of the
HIV/AIDS Epidemics in Africa Workshop held in Kampala, Uganda,
in December 1995 prior to the IX International Conference on AIDS
and STD in Africa.
With specific
recommendations for urgent action to prevent the further spread
of HIV in Africa, the Kampala workshop report raised issues that
cut across HIV/AIDS epidemics in developing countries globally
and provided a successful model for future action-oriented international
HIV/AIDS symposia. The workshop report, released during the Kampala
conference and quickly disseminated internationally by the workshop
organizers, became available for immediate programmatic reorientation,
planning and implementation by policy makers and program managers
working on HIV/AIDS-related issues in Africa and around the world.
Seizing on
the impact of the Kampala initiative, the workshop’s co-chairs,
Daniel Tarantola of Harvard’s François-Xavier Bagnoud Center and
Peter Lamptey of AIDSCAP, quickly convened a larger Symposium
on The Status and Trends of the Global HIV/AIDS Pandemic at the
XI International Conference on AIDS in Vancouver, Canada, which
they also co-chaired. The objectives for the Vancouver Symposium
included: reviewing the current status and trends of the global
HIV/AIDS pandemic, including the epidemiological and behavioral
patterns; identifying the specific data needs for monitoring and
forecasting; and producing a consensus report on the global pandemic
and on current as well as projected trends for the epidemics in
various parts of the world.
Ten regional
teams composed of 50 leading epidemiologists, public health and
development specialists (see List of Participants, Page 58), each
nominated by an international steering committee, were chosen
to collect and analyze data and information on the status and
trends of HIV/AIDS in their region prior to the Symposium. Regional
working group sessions held by each team on site provided the
basis for summary presentations to the Symposium participants.
Finally, a plenary discussion was held on each region at which
the Symposium participants reached conclusions and made their
final recommendations for this report.
Released within
24 hours of the Symposium’s conclusion, the provisional Vancouver
report was amended during the Vancouver conference to the version
herein. A day later, the Vancouver Symposium organizers began
planning the next Status and Trends of the HIV/AIDS Pandemic Symposium
to be convened at the 4th International Conference on AIDS in
Asia and the Pacific, to be held in Manila, Philippines, in October
1997.
Executive
Summary
Globally,
the HIV/AIDS pandemic continues to sweep across continents: the
number of estimated adult HIV infections worldwide has more than
doubled since 1990 from 10 million to a mid-1996 total of 25.5
million. Composed of distinct epidemics, each with its own features
and force, the pandemic is disproportionately impacting the developing
world. HIV infections, however, are leveling off and even decreasing
in some populations. HIV incidence has declined in young women
in Uganda, young men in Thailand and in gay men in the U.S., Australia,
Canada and western Europe.
From the beginning
of the pandemic until mid-1996, an estimated 27.9 million people
worldwide were infected with HIV. Of these, 14.9 million were
men (58 percent) and 10.5 million were women (42 percent). The
majority of HIV infections- 26 million (93 percent) -have occurred
in developing countries. The largest numbers of HIV-infected individuals
were in sub-Saharan Africa, totaling 19 million (68 percent of
the global total), and in South and Southeast Asia, totaling 5
million (18 percent of the global total). The number of HIV-infected
people in South and Southeast Asia is now more than twice the
total number of those infected in the entire industrialized world.
Worldwide, 5.8 million people (4.5 million adults and 1.3 million
children), 75 percent of all those with AIDS, are estimated to
have died from AIDS.
Sub-Saharan
Africa, representing about 60 percent of the world’s total
HIV infections, accounts for almost 90 percent of the current
13.3 million HIV infections in adults and adolescents in Africa.
The rates of newly acquired HIV infections are highest in the
15- to 24-year-old group among both females and males in most
of sub-Saharan Africa. Of the 3 million HIV-infected infants born
in the world with HIV infection since the beginning of the pandemic,
over 90 percent have been born in Africa. Many of these children
typically develop AIDS and die within a few years.
Eighteen countries
in the region have at least 100,000 people living with HIV. Central
and East African countries have 37 percent of all current HIV
infections on the continent. A second group of countries in southern
Africa contributes about 15 percent to the total number of adults
and adolescents living with HIV in the region. In other sub-Saharan
countries- mostly in west and central Africa -HIV epidemics are
currently passing through their intermediate stage where between
1 and 10 percent of women attending urban antenatal clinics are
HIV-infected. In contrast to the increasing spread of HIV-1, the
prevalence of HIV-2 has remained rather stable in West Africa,
perhaps the result of the higher transmissibility of HIV-1 compared
to HIV-2.
Urban and
trading centers generally show substantially higher prevalence
of HIV infection than rural areas; however, rates of HIV infection
in some rural populations have increased steadily. Open conflicts,
environmental degradation, natural disasters and low-intensity
wars also have led millions of Africans to leave their homes and,
in some situations, to turn to survival strategies that have increased
the practice of unsafe sex. Migration and urbanization also have
led to high concentrations of predominantly male communities and
increased participation in commercial sex.
Demographic
surveys in several countries have already noted significant increases
in infant and child mortality. Projections for Zambia and Zimbabwe
indicate that AIDS may increase child mortality rates nearly threefold
by the year 2010. Due to high levels of fertility, populations
will generally continue to grow, but critical deficits will affect
the economically active age groups.
Asia,
home to more than 60 percent of the world’s adult population,
presents epidemiology and HIV prevalence estimates that are extremely
diverse, ranging from countries with low prevalence (Mongolia,
DPR Korea) to countries with high prevalence (Cambodia, Myanmar
and Thailand). HIV is spreading mostly through heterosexual contact.
Infected men probably outnumber infected women by a factor of
3 to 1 or more, and gender inequality and the frequent practice
of men visiting sex workers have strongly influenced spread of
HIV. Sharing of needles among injecting drug users (IDUs) also
played a significant role early in the epidemics, particularly
in the Golden Triangle region (from Thailand and Vietnam, across
southern China, to Myanmar and Manipur State in India) and in
northern Malaysia.
Thailand has
an estimated three-quarters of a million people living with HIV.
Yet there is evidence that Thailand's active multi-sectoral prevention
efforts are taking effect, as HIV infection levels in military
conscripts have dropped from 3.6 percent in 1993 to 2.5 percent
in 1995. Pediatric HIV infection is difficult to assess regionally,
but an estimated 6,400 children are infected annually in Thailand,
making up approximately 10 percent of the new infections of HIV.
Evidence in
India suggests rapid, extensive and uncontrolled spread of HIV
in many parts of the country, and HIV seroprevalence is high in
the South and West. In Bombay, prevalence went from 2 to 3 percent
in sexually transmitted disease (STD) clinic attendees before
1990 to 36 percent in 1994. Injecting drug use has been a problem
in Manipur State, where prevalence reached 60 percent by 1992.
Evidence suggests an estimated 2 to 5 million HIV infections nationwide
in mid-1996. Low use of condoms and high rates of sexually transmitted
disease continue to be a major problem in India, threatening to
multiply exponentially the spread of HIV.
In Cambodia
data indicate that the current extensive HIV epidemic started
during the late 1980s or early 1990s and is predominantly occurring
among heterosexuals with multiple sex partners. Myanmar has one
of the most serious epidemics in the region, with an estimated
half a million people infected with HIV by 1996. In Malaysia HIV
infection levels in IDUs have grown rapidly from 0.1 percent in
1988 to 20 percent in 1994.
In Vietnam,
evidence shows the HIV epidemic to be growing rapidly, with high
levels in IDUs in treatment (32 percent in 1992-95), and increasing
levels among young men and women in the south.
China, because
of its size and rapid changes in social and sexual behavior, represents
another major potential focus of the epidemic in Asia. The majority
(about 70 percent) of reported HIV infections and AIDS cases have
been among IDUs in Yunnan Province, but infections are believed
to be increasing among heterosexuals in southern China, especially
in the areas surrounding Hong Kong. An estimated 10,000 persons
were infected with HIV in China at the end of 1993, growing to
100,000 by the end of 1995.
HIV transmission
may be starting in the heterosexual population in Laos. Bangladesh,
Indonesia, Nepal and Sri Lanka show high levels of other STDs,
implying a strong possibility for extensive HIV spread. In Hong
Kong, Japan, Mongolia and the Republic of Korea, extensive spread
has not been documented. No cases of AIDS or HIV have been reported
in DPR Korea or Bhutan. In the Philippines the epidemic shows
slower growth, and in Singapore, HIV infection levels in sex workers
have been growing quite slowly.
In Latin
America and the Caribbean the spread of HIV/AIDS has been
slower than in other regions, but the pandemic is well-established
and some Caribbean countries report AIDS incidence rates among
the highest in the world. Dominant modes of transmission vary
from one country to the next: mainly through homo- and bisexual
contacts in some countries, to epidemics connected to injecting
drug use in others, to still others primarily determined by heterosexual
transmission. Epidemiological evidence signals a rapid shift of
new infections to younger ages, particularly to young people between
15 and 24 years old.
The number
of new HIV infections in Mexico, Guatemala, Belize, El Salvador,
Honduras, Nicaragua, Costa Rica, Panama, Cuba, Dominican Republic,
Haiti and Puerto Rico continues to rise, reflecting increasing
HIV/AIDS incidence and accelerated heterosexual transmission.
Haiti is of
particular importance because, perhaps alone in the region, it
represents a relatively mature epidemic. HIV prevalence is particularly
high among sex workers, STD clinic attendees and tuberculosis
(TB) patients. High rates of HIV prevalence are found among pregnant
women aged 14 to 24.
In the English-speaking
Caribbean, the male-to-female ratio of new AIDS cases has fallen
dramatically over the past 10 years, under 2 men to 1 woman in
1994. Women aged 15 to 19 now have higher annual incidence rates
than men of the same age. AIDS is the leading cause of death among
young men in some Caribbean countries, while pediatric AIDS cases
have been steadily rising and now account for 5 percent of all
new cases. The extremely low incidence of HIV infection through
contaminated blood represents a partial success story for the
Caribbean region.
HIV infections
and AIDS cases in South America are rising steadily. Brazil accounts
for 75 percent of AIDS cases reported and is followed by the Andean
Region (15 percent) and the Southern Cone (10 percent). Sexual
transmission of HIV accounts for 74 percent of all infections
(51 percent homo/bisexual and 23 percent heterosexual), injecting
drug use 19 percent (although recent data in Brazil suggests that
the HIV transmission through injecting drug use seems to be leveling
off) and 7 percent for blood and vertical transmission and undocumented
cases.
The impact
of HIV/AIDS on morbidity and mortality is being seen in major
urban centers, such as in São Paulo, Brazil, where AIDS is now
the leading cause of death in women of reproductive age.
North America
has seen the HIV epidemic slow in recent years as new infections
start to level off, largely due to the decline in sexual transmission
between men as a result of behavior change. Nevetheless, HIV prevalence
in gay men remains high on the continent. In the United States,
HIV prevalence among IDUs has decreased. AIDS cases related to
heterosexual contact represent an increasing proportion of newly
diagnosed cases in North America.
Since the
start of the epidemic from 1 to 1.5 million cumulative HIV infections
have occurred in North America, and HIV infection has been one
of the major causes of death for individuals between the ages
of 25 and 44. Among men in this age group, it was the leading
cause of death in the U.S. and the second leading cause of death
in Canada in 1994. In the same year, HIV infection was the third
leading cause of death among 25- to 44-year-old women in the U.S.
An estimated 12,000 children in the U.S. are living with HIV,
although AIDS incidence among children under 13 has declined annually
since 1990.
Although there
has been an overall slowing in AIDS incidence, there has been
substantive shift in the populations affected. In 1995 AIDS incidence
was 6.5 times greater for blacks and 4 times greater for Hispanics
than for whites, 20 percent of persons diagnosed with AIDS were
women, and 15 percent were infected heterosexually. AIDS among
prisoners was 7 times the rate of the non-incarcerated population,
and AIDS was the second leading cause of death among prisoners.
In Europe
an estimated 450,000 adults were living with HIV in western Europe
at the end of 1993, with an annual incidence of around 40,000
since 1990. Over the past 2 to 3 years, AIDS incidence appears
to have stabilized in several countries in northwestern Europe
and condom use increased markedly, particularly for the most sexually
active population groups. In contrast, countries in southwestern
Europe show no indication of AIDS leveling off.
Transmission
of HIV through injecting drug use continues to play a major role
in the dynamics of the epidemic. It is responsible for the majority
of AIDS cases in some of the western countries with highest incidence
(Spain and Italy) and is strongly associated with AIDS cases occurring
among heterosexual adults and among children in these countries.
Transmission
of HIV through injecting drug use continues to play a major role
in the dynamics of the epidemic. It is responsible for the majority
of AIDS cases in some of the western countries with highest incidence
(Spain and Italy) and is strongly associated with AIDS cases occurring
among heterosexual adults and among children in these countries.
In central and eastern Europe (with the exception of Romania)
and central Asia, the HIV/AIDS epidemic is much more recent and
AIDS incidence much lower than in western Europe. In some countries,
a rapid spread of HIV is indicated, mainly linked with injecting
drug use. In Poland and the Federal Republic of Yugoslavia, where
IDUs account for the largest proportion of cases, the incidence
of AIDS is rising rapidly.
Before 1990,
most AIDS cases were diagnosed in men who have sex with men (MSM).
Since 1990, however, IDUs account for the highest proportion of
yearly diagnosed cases in the region (43 percent of adult and
adolescent cases in 1995). The shift in transmission patterns
is accompanied by an increase in the proportion of female cases,
which rose from 11 percent in 1986 to 20 percent in 1995.
The vast majority
of children have been infected through mother-to-child transmission,
and HIV prevalence in pregnant women has been much higher in urban
than in rural areas. The epidemic among children is dominated
by the epidemic in Romanian hospitals, which was detected in 1989
and accounts for over 50 percent of the 6,060 pediatric cases
reported in the European region. Another, though much smaller,
epidemic among children in hospitals occurred in the Russian Federation
in the late 1980s.The most worrisome information coming from STD
surveillance arose recently from the independent republics of
the former Soviet Union. Substantial increases in syphilis rates
have been seen since 1990 in several of these states.
In the North
and South Pacific around 7,400 cases of AIDS had been reported
by the end of 1995, with over 7,000 of them in Australia and New
Zealand, where the major pathway of HIV transmission (about 85
percent of HIV infections) has been through sexual contact between
men. This pattern also has been reflected in the French Territories
of New Caledonia and French Polynesia. The HIV epidemic in Papua
New Guinea (PNG) has developed more recently and appears to involve
a major component of heterosexual transmission; by the end of
1994 PNG had an estimated 4,000 adults living with HIV, overtaking
Australia on a per-capita basis to give the highest prevalence
in the region.
The incidence
of AIDS has reached a plateau in Australia, and appears to be
declining in New Zealand, due to the drop in the rate of sexual
transmission of HIV between men that mostly occurred ten years
earlier. In Australia, and to a lesser extent New Zealand, high
rates of STDs other than HIV in indigenous people have led to
mounting concern about the potential for a major heterosexual
epidemic of HIV infection in these populations, among whom the
rate of HIV diagnosis has increased in the past six years.
In conclusion,
the HIV/AIDS pandemic is as powerful as ever: HIV continues to
spread in the industrialized world, where, increasingly, it affects
people who, for reasons of race, sex, behavior or social and economic
status, have lesser access to services. From a global perspective,
the pandemic disproportionately affects the developing world,
where the needs for effective prevention and care are escalating.
But the pandemic has now become immensely complex. It has become
fragmented and is now a mosaic composed of a multitude of epidemics,
which can be distinguished on the basis of: predominant modes
of transmission; geographic focus; HIV sub-types; age, sex, socioeconomic
or behavioral characteristics of the populations most affected;
rapidity of or potential for HIV spread; stage of maturity and,
in some communities and countries, declining HIV incidence.
As the HIV
epidemics pursue their course, the social, economic and demographic
impacts of HIV/AIDS in particular in the developing world are
likely to exacerbate the burden on individuals, communities and
countries, which will challenge the stability of entire regions.
Current evidence
of the effectiveness of HIV prevention and recent progress achieved
in the development of new therapies provide the scientific basis
on which an expanded response to growing prevention and care needs
can be built.
Existing epidemiological
surveillance systems are inadequate to monitor the HIV epidemics
effectively. Creativity and sustained effort must be applied to
collect and analyze data that better reflect and will help understand,
predict and prevent the dynamic spread of HIV in vulnerable populations
worldwide.
Global
Overview
In mid-July
1996, an estimated 21.8 million adults and children worldwide
were living with HIV/AIDS, of whom 20.4 million (94 percent) were
in the developing world. Of the adults, 12.2 million (58 percent)
were male and 8.8 million (42 percent) were female (For more
details, see "The HIV/AIDS Situation in mid-1996, Global and Regional
Highlights. Fact Sheet 1 July 1996," UNAIDS and WHO, Geneva, Switzerland).
Close to 19 million adults and children (86 percent of the world
total) were living with HIV/AIDS in sub-Saharan Africa and in
South and Southeast Asia.
Worldwide
during 1995, 2.7 million adult HIV infections occurred in adults
(averaging more than 7,000 new infections each day). Of these,
about 1 million (an average of nearly 3,000 new infections per
day) occurred in Southeast Asia and 1.4 million infections (close
to 4,000 new infections per day) were in sub-Saharan Africa. The
industrialized world accounted for about 55,000 new HIV infections
in 1995 (nearly 150 new infections per day; about 2 percent of
the global total).
In 1995 approximately
500,000 children were born with HIV infection (about 1,400 per
day); of these children 67 percent were in sub-Saharan Africa,
30 percent in South and Southeast Asia, and over 2 percent in
Latin America and the Caribbean.
From the beginning
of the pandemic until mid-1996, an estimated 27.9 million people
worldwide have been infected with HIV. The largest numbers of
individuals ever infected with HIV were in sub-Saharan Africa,
totaling 19 million (68 percent of the global total), and in South
and Southeast Asia, totaling 5 million (18 percent of the global
total).
Since the
beginning of the pandemic, the majority of HIV infections- 26
million (93 percent) -have occurred in the developing world. The
number of HIV-infected people in South and Southeast Asia is now
more than twice the total number of infected people in the entire
industrialized world.
The global
cumulative number of HIV infections among adults has more than
doubled since the beginning of the decade, from about 10 million
in 1990 to almost 25.5 million by mid-1996. Of these, 14.9 million
were men (58 percent) and 10.5 million were women (42 percent).
More than
6 million adults have developed AIDS from the beginning of the
pandemic to July 1996, and of these 4.5 million (close to 75 percent)
were in sub-Saharan Africa; 0.4 million were in Latin America
and the Caribbean (7 percent); and 0.75 million were in North
America, Europe and North and South Pacific combined (12 percent).
In South and Southeast Asia, where the pandemic gained intensity
more recently, it is estimated that 330,000 adults have developed
AIDS. Of the 1.6 million children with AIDS, the majority- 1.4
million (85 percent) -were in sub-Saharan Africa.
By July 1996,
5.8 million people (4.5 million adults and 1.3 million children),
75 percent of all people with AIDS, are estimated to have died
from AIDS worldwide.
In summary,
the HIV/AIDS pandemic is as powerful as ever. This report will
show that the pandemic is now composed of distinct epidemics each
with their own features and force, and disproportionately impacting
on the developing world. The following sections of this report
will show that as the HIV/AIDS epidemics within each region and
country have become increasingly diverse and fragmented, they
have created a multifaceted and devastating pandemic.
Africa
And The Middle East
Sub-Saharan
Africa by mid-1996, 13.3 million adults were living with HIV in
sub-Saharan Africa, representing about 60 percent of the world’s
total. Three broadly defined geographic areas, which include countries
with severe epidemics and others with epidemics at their intermediate
stages, account for almost 90 percent of all current HIV infections
in adults and adolescents in Africa. Within these three areas,
18 countries have at least 100,000 people living with HIV. In
central/eastern Africa, Cameroon, Ethiopia, Kenya, Rwanda, Sudan,
Uganda and Zaire have 37 percent of all current HIV infections
on the continent. A similar proportion is contributed by a second
group of countries in southern Africa: Botswana, Malawi, Mozambique,
South Africa, Tanzania, Zambia and Zimbabwe. Finally, West African
countries, including Burkina Faso, Côte d’Ivoire, Ghana and Nigeria,
contribute about 15 percent to the total number of adults and
adolescents living with HIV in Africa.
In Kenya,
Malawi, Rwanda, Tanzania, Uganda, Zambia, Zimbabwe (countries
where HIV began to spread widely in the early 1980s), more than
10 percent of women attending antenatal clinics surveyed in urban
areas have been found to be HIV-infected, with rates which may
exceed 40 percent in some surveillance sites. In these populations,
transmission of HIV occurs mainly through heterosexual contact,
beginning in early teen years and peaking before age 25. Following
similar patterns of spread and intensity, HIV epidemics have recently
expanded in Botswana, Lesotho, Swaziland and South Africa. The
observed high rates of HIV in women of reproductive age have resulted
in high numbers of HIV-infected newborns. Of the 3 million HIV-infected
infants born in the world with HIV infection since the beginning
of the pandemic, over 90 percent have been born in Africa. Many
of these children typically develop AIDS and die within a few
years.
In other sub-Saharan
countries (mostly in west and central Africa)HIV epidemics are
currently passing through their intermediate stage where between
1 and 10 percent of women attending urban antenatal clinics are
HIV-infected. A few of these countries still have relatively low
levels of HIV prevalence, but these have begun to rise in several
countries such as Nigeria and Cameroon, which earlier had been
relatively spared. HIV-2 is primarily found in West Africa, but
HIV-2 infections also have been confirmed in African countries
elsewhere, including Angola and Mozambique. The highest prevalence
of HIV-2 infection is found in Guinea Bissau and in southern Senegal.
In contrast to the increasing spread of HIV-1, the prevalence
of HIV-2 has remained rather stable in West Africa. This is thought
to be the result of the higher transmissibility of HIV-1 compared
to HIV-2. The likelihood of transmission of HIV-1 through heterosexual
intercourse is estimated to be about three times higher per exposure
than for HIV-2. In addition, perinatal transmission rates of HIV-2
are reported significantly lower (less than 4 percent for HIV-2
compared with 25 to 35 percent for HIV-1).
Under circumstances
that are not yet fully understood, epidemics may suddenly explode,
with rates of infection increasing several fold within only a
few years, as has been observed recently in Botswana and South
Africa. HIV prevalence in pregnant women in South Africa has grown
dramatically. From 1993 to 1995, HIV prevalence increased from
4.3 to 11 percent, and from 9.6 to 18 percent, in the provinces
of Free State and Kwazulu/Natal, respectively. Population mobility,
patterns of sexual behavior, and societal factors are likely to
influence the potential for such explosions.
The presence
of sexually transmitted diseases (STDs) suggests a marked risk
of concurrent HIV infection for at least two reasons: (1) the
modes of transmission of HIV and other STDs are similar; and (2)
the role of STDs in facilitating the transmission of HIV has been
clearly established. STDs are affecting young adults, especially
women, with direct serious consequences. For women, these consequences
include pelvic inflammatory disease, cervical cancer, infertility
and post-partum endometritis. For infants, maternal STDs may lead
to low birth weight, neonatal syphilis and gonococcal opthalmia.
The lack of circumcision in males has been shown to add to the
risk of acquiring STDs. The World Health Organization estimates
that in 1995, 65 million new cases of curable STDs occurred in
Africa.
Populations
Affected
The transmission
of HIV in adults and young people in sub-Saharan Africa occurs
essentially through heterosexual contact. Rates of HIV infection
among sex workers are now found as high as 80 percent in Nairobi
and 55 percent in Abidjan. HIV antibody testing of blood donations
remains incomplete in most countries in sub-Saharan Africa. Transfusions
continue to play a role in the spread of HIV to those most likely
to receive them: women of reproductive age and children.
Within each
country, HIV epidemics have progressed with different velocity
in various population groups. Early in the evolution of the epidemics,
urban populations and rural communities located along highways
were more rapidly affected. Among them, young adults with multiple
sexual partners acquired high rates of infection. Urban and trading
centers generally continue to have substantially higher prevalence
of HIV infection than rural areas. But, this pattern is by no
means universal: population displacement, armed conflicts, proximity
to highways or intense migration and population mobility for economic
reasons influence strongly the spread of HIV.
As a result
of a combination of these factors, some rural communities of Kenya,
Tanzania and Uganda have higher infection rates than those observed
in neighboring urban populations. In some countries where HIV
epidemics were initially found in urban areas, rates of HIV infection
in some rural populations have increased steadily over recent
years. In other countries, perhaps with poorer transport networks,
this has not been the case.
As a result
of a combination of these factors, some rural communities of Kenya,
Tanzania and Uganda have higher infection rates than those observed
in neighboring urban populations. In some countries where HIV
epidemics were initially found in urban areas, rates of HIV infection
in some rural populations have increased steadily over recent
years. In other countries, perhaps with poorer transport networks,
this has not been the case. As epidemics mature, they tend to
spread into younger populations, especially young women. The rates
of newly acquired HIV infections are highest in the 15- to 24-year-old
group among both females and males in most of sub-Saharan Africa.
The peak of new infections occurs several years earlier in young
women than in young men. In Masaka, Uganda, for example, HIV prevalence
in 13- to 19-year-old females is over 20 times higher than in
males of the same age. Most of the infections in 15- to 19-year-olds
are in females, although as young men get older, their prevalence
increases as well.
Apart from
possible biological factors, there are at least two reasons for
the disproportionate risk of young women acquiring HIV infection
early, including: (1) an earlier age of sexual initiation of girls
(in Masaka, the median age at first sexual intercourse is 15 for
females and 17 for males); and (2) the patterns of sexual mixing,
wherein young women tend to have sex with older men in the context
of marriage or in exchange for money or advantages, whereas young
men tend to have sex with young women. But for many women, the
major risk factor for HIV is the behavior of their spouse or regular
sexual partner. Monogamous women are at a disadvantage in protecting
themselves against HIV when spouses are engaged in high-risk behavior.
Populations
on the Move
Major political,
social and demographic changes have occurred in sub-Saharan Africa
over the last few decades and have resulted in important population
displacement, migration and rapid urbanization. The improvement
of transportation and communication networks, the increased exchange
of goods, and the creation of large-scale development programs
have stimulated the movement of young men and women within and
across national boundaries. Open conflicts, environmental degradation,
natural disasters and low-intensity wars have also led millions
of Africans to leave their places of residence and, in some situations,
to turn to survival strategies that have increased the practice
of unsafe sex. Consequences of political and civil unrest and
subsequent population displacement have led to an increased spread
in HIV transmission; populations displaced from Ethiopia, Mozambique,
Rwanda and Liberia are examples. In addition, the movement of
troops from West
Africa to Angola and Mozambique has been linked to the spread
of HIV-2 to these countries.
Migration
within countries, across borders, and urbanization (e.g., from
rural areas to urban centers or industrial sites) have led to
high concentrations of predominantly male communities and increased
participation in commercial sex. Professional groups characterized
by mobility, for instance, truck drivers, traders and military
personnel, have also been associated with a higher risk of HIV
infection. Population mobility facilitates the spread of STDs,
including HIV.
Economic development
programs (the construction of highways, dams, and the creation
of new industries or agriculture projects, for example) need to
include an initial appraisal of the potential impact of these
projects on the vulnerability of the labor force and the local
population to HIV infection and other STDs. Measures to minimize
this impact, such as reducing gender imbalance in the labor force,
enabling workers to be joined by their families, allowing for
regular contacts with distant spouses, and incorporating HIV/STD
programs in development schemes, need to be built into the project
design. But even with such initiatives, the sheer dynamic of transition
towards increasingly urbanized society brings with it changing
behavior mores that create new needs and present new opportunities
for HIV transmission.
All of these
social and demographic changes need to be addressed by well-designed
national and inter-country HIV/STD prevention programs based on
epidemiological, behavioral and social determinants research.
Burden
of Disease
Although the
constantly growing HIV/AIDS care needs have already overwhelmed
the coping capacity of urban health systems in hard-hit countries,
demands for care will increasingly fall on poorly equipped and
under-funded rural services, households and individuals. Already,
80 percent of hospital beds in an infectious disease hospital
in Abidjan, Côte d’Ivoire, and 50 percent in a hospital in Kampala,
Uganda, are occupied by people with HIV.
Demographic
surveys in several countries have already noted significant increases
in infant and child mortality. Projections for Zambia and Zimbabwe
indicate that AIDS may increase child mortality rates nearly threefold
by the year 2010. Other estimates point to a more modest impact.
In either case, due to high levels of fertility, populations will
generally continue to grow, but critical deficits will affect
the economically active ages. Studies in areas where 8 percent
of the adult population is HIV-infected have measured a doubling
of mortality due to HIV and a decrease of 5 years in life expectancy.
Some HIV epidemics will have severe effects on the population
age structure, indenting the population pyramid in young adults,
the main contributors to social and economic development, but
this may not occur in all areas.
Successes
in Prevention
To date in
sub-Saharan Africa, there has been a lack of rigorous evaluation
of intervention strategies, especially for the behavioral interventions
designed to reduce the sexual transmission of HIV. Without good
behavioral, social and contextual data, however, it is difficult
to attribute observed changes in HIV prevalence rates to specific
program efforts. STD control programs, through early diagnosis,
treatment and the promotion of safer sexual behavior, have been
shown to reduce significantly the rates of STD infections. Successful
programs have been documented in Zambia and Zimbabwe. In a research
study in Mwanza, Tanzania, early treatment of STDs in a rural
population has been associated with a 42 percent decline in the
rate of newly acquired HIV infections. Emerging data also show
substantial decline in some STDs. This important finding supports
the revitalization of STD control programs benefiting from new
approaches that have already been initiated in several sub-Saharan
countries.
Treating
Sexually Transmitted Diseases Reduces HIV Incidence: Result of
the Mwanza, Tanzania Trial
- One of
the key advances in HIV/AIDS research over the past year has
been the confirmation that treating sexually transmitted diseases
(STDs) reduces the incidence (rate of new infections) of HIV.
This evidence arises from the Mwanza trial, the first randomized
controlled trial to demonstrate the impact of preventive measures
against HIV in a general population setting.
- The aim
of the Mwanza trial was to implement improved STD treatment
services for the rural population of this northern Tanzanian
region. These services were fully integrated into the primary
health care system based on the syndromic treatment method (not
requiring laboratory diagnosis) recommended bt the World Health
Organization. The services were designed to be affordable and
replicable on a large scale in resource-poor settings, and their
impact was measured in a randomized trial: six communities with
the improved STD services (the intervention group) were compared
with six matched comparison communities with pre-existing STD
services (the comparison group).
- A random
sample of 12,000 adults in Mwanza was followed over two years
to record HIV incidence and the prevalence (proportion of infections
in a population) of selected STDs. HIV prevalence at baseline
was about 4 percent in both the intervention and comparison
groups. Incidence of HIV infections over two years was 1.2 percent
in the intervention communities, compared with 1.9 percent in
the comparison communities, showing a reduction of about 40
percent from the intervention. Reductions were seen in all age
and sex groups.
- Data from
Mwanza also show a substantial impact from the intervention
on some of the STDs targeted by the treatment program: active
syphilis was reduced by 30 to 40 percent, and in men the prevalence
of symptomatic urethristis was reduced by 50 percent.
- There was
little effect from the Mwanza intervention on asymptomatic STDs,
which are common in both women and men in this population. Because
symdromic treatment services rely on patients perceiving STD
symptoms, the significant impact on symptomatic but not asymptomatic
STDs is not surprising.
- A detailed
economic evaluation showed that the annual cost of the Mwanza
intervention program for a population of 150,000 was about US$68,000,
or about 45 cents per capita. The cost per case of HIV infection
averted was about $250, or $11 for each year of healthy life
saved. This compares favorably with child immunization programs
and other highly cost-effective health interventions.
- Results
from Mwanza suggest that a large proportion of HIV infections
in this population are due to the enhancing effects of other
STDs, particularly when these are symptomic. This may help to
explain the very rapid spread of HIV in some parts of Africa
and other regions of the developing world. The Mwanza trial
has shown that providing effective treatment services for such
STDs can significantly reduce their prevalence and the number
of new HIV infections.
- The economic
data from Mwanza show that improved STD treatment services are
not only effective, but highly cost-effective and should, therefore,
be promoted as an essential component of HIV/AIDS control activities
wherever STDs are highly prevalent. Large-scale implementation
of STD treatment services could have a major impact on the HIV
pandemic worldwide.
Hope that
the number of new infections occurring may have decreased comes
from studies of the epidemic in Uganda, a country with one of
the older epidemics in Africa. A study of recent trends in HIV
infection in women attending several antenatal clinics in Uganda
shows significant declines in HIV prevalence. Between 1990-93
and 1994-95, overall HIV prevalence in pregnant women at sentinel
sites decreased 29 percent (from 21 to 15 percent), and decreased
35 percent in both 15- to 19- and 20- to 24-year-olds. Since infection
levels (prevalence) in this young age group reflect more recent
patterns in new infections (incidence), these data suggest a substantial
reduction in the incidence of HIV infection in young people over
time.
Declines
in HIV Incidence and Prevalence in Pregant Women and their Relationship
to HIV Risk Reduction in Uganda from 1989 to 1995
- In Uganda,
recent trends in HIV prevalence (proportion of people infected)
in pregnant women detected by sentinel HIV surveillance in urban
areas indicate that a substantial decline has occured in recent
HIV incidence (proportion of new infections) in young women.
- From 1990
to 1993 and from 1994 to 1995, HIV prevalence in pregnant women
at sentinel sires in Uganda decreased overall by 29 percent
(from 21 percent to 15 percent), and by 35 percent in both 15-
to 19-year-olds (from 17 percent to 11 percent) and in 20- to
24-year-olds (27 percent to 17 percent). These findings are
consistent with a reduction of 30 to 50 percent in HIV incidence
in female adolescents and young women in Uganda since 1988.
- Population
surveys to assess the determinants of declining HIV incidence
in Uganda suggest that changes could be due largely to a reduction
in high-risk behavior, including: increased monogamy; reduction
in numbers of sexual partners; condom use in sexual relationships
at risk of HIV infection; and later age of sexual debut. For
example, in 1995 in Kampala, 22 percent of male respondents
reported sex with a non-regular partner, of whom 63 percent
reported use of a condom in the last sexual encounter at risk
of HIV infection.
- A decline
in HIV incidence is the most pausible explanation for the observed
trends in Uganda, and such changes could result from a reduction
in high-risk sexual behavior.
- These findings
provide evidence that prevention strategies to change high-risk
sexual behavior in Uganda may have had a direct impact on reducing
the rate of new HIV infections in some areas of the country.
- Additional
studies are required to better identify the determinants of
such sexual behavior change in Uganda and assess the extent
to which these findings can be applied to other HIV epidemics
in sub-Saharan Africa.
Similar declines
in HIV prevalence in young adults are reported from another study
in the Masaka district in Uganda. These findings could indicate
that the growth of the epidemic has been blunted, perhaps transiently,
by behavioral changes resulting in decreased spread of HIV in
younger age groups. Surveys of such populations suggest that behavior
change might have led to these apparent declines; however, more
rigorous qualitative and quantitative behavioral and social data
will be required to help interpret these results.
Notwithstanding
these encouraging signs, new infections remain high, especially
in young people. The combination of reductions in levels of infection
and continuing evidence of new infections should provide additional
impetus for enhancing prevention efforts.
North
Africa And The Middle East
This region
represents 22 countries ranging from Morocco in the west to Pakistan
in the east. Information on HIV infection in the region is sparse.
Information available from mandatory screening of blood donors
indicates low HIV prevalence in these populations, except for
Djibouti.
The highest
levels of HIV infection have been documented in Djibouti (9.3
percent in pregnant women and from 2 to 20 percent in STD patients).
HIV prevalence among STD patients rose from 1.3 to 5 percent in
Sudan; this pattern has also been seen in Yemen, Pakistan and
the Syrian Arab Republic. Seventy-five percent of reported AIDS
cases are from five countries in the region: Morocco, Sudan, Saudi
Arabia, Tunisia and Djibouti.
The future
size and trends of the epidemic in this region are difficult to
predict. There is anecdotal evidence of high STD rates and risk
behaviors. The region is characterized by late introduction of
the virus, the status of women in society, the highly stigmatizing
nature of STDs, and the difficulty of conducting effective sexual
health programs.
Asia
This region
includes Bangladesh, Bhutan, Brunei Darussalam, Cambodia, China,
India, Indonesia, Hong Kong, Japan, DPR Korea, Republic of Korea,
Laos, Malaysia, the Maldives, Mongolia, Myanmar, Nepal, the Philippines,
Singapore, Sri Lanka, Thailand and Vietnam. It is home to over
60 percent of the world’s adult population, hence what happens
in the region will have a major impact on the global pandemic.
The general
epidemiology and estimated prevalence rates for these countries
are extremely diverse, ranging from countries with low HIV prevalence
rates (Mongolia, DPR Korea) to countries with high HIV prevalence
(Cambodia, Myanmar and Thailand).
There has
been substantial variation in the timing and rate of growth of
the epidemic. In some countries, e.g., Cambodia, India, Myanmar
and Thailand, HIV spread has been extensive, with extremely rapid
growth in some geographic areas. In others, e.g., DPR Korea and
the Republic of Korea, the Philippines and Singapore, only limited
spread has occurred to date and the rate of growth appears to
be substantially lower.
The epidemic
in Thailand is among the best documented in the world, with an
estimated three-quarter of a million people living with HIV. Nationally,
HIV prevalence among injecting drug users rose quickly in 1988
to approximately 35 percent. HIV among brothel-based sex workers
rose from 3.5 percent in 1989 to 33 percent by late 1994. Infection
levels in males at STD clinics grew from 0 percent to 8.6 percent
over the same time period. HIV prevalence in women attending antenatal
clinics has continued to rise steadily from 0 percent in 1989
to 2.3 percent in 1995. This trend is expected to continue for
several years. However, there is evidence that prevention efforts
are taking effect; HIV infection levels in military conscripts
have dropped from 3.6 percent in 1993 to 2.5 percent in 1995.
In India HIV
seroprevalence is high in the south and west. For example, in
Bombay prevalence went from 2 to 3 percent in STD clinic attendees
before 1990 to 36 percent in 1994. HIV prevalence in sex workers
rose from 1 to 51 percent between 1987 and 1993, and antenatal
clinic women tested positive at a 2.5 percent rate in 1994. There
is great geographical variation in India. HIV seroprevalence in
the central, eastern and northern parts of the country are generally
lower than in the rest of India. Studies among sex workers in
Calcutta have shown a clear and consistently low prevalence of
1.2 percent. In Vellore rates among women attending antenatal
clinics have been steady at 0.1 percent, although STD clinic rates
there grew from 4 percent to 15 percent between 1993 and 1995.
Injecting drug use has been a problem in Manipur State, with prevalence
reaching 60 percent by 1992. This geographic variability and the
size of the country have made estimation of the actual number
of infections difficult. At the end of 1994, WHO estimated 1.75
million HIV infections, while evidence suggests an estimate of
between 2 and 5 million in mid-1996.
HIV/AIDS
in India
- India is
experiencing rapid and extensive spread of HIV. This is particularly
worrisome since India is home to a population of over 900 million.
As a single nation it has more people than the continents of
Africa, Australia and Latin America combined.
- There are
an estimated 2 to 5 million people infected with HIV in India
today, and 50,000 to 100,000 cases of AIDS may have already
occured in the country.
- This epidemic
is hueled by both married and unmarried men visiting sex workers.
- The most
rapid and well-documented spread of HIV has occured in Bombay
and the State of Tamil Nadu. In Bombay HIV prevalence has reached
the level of 50 percent in sex workers, 36 percent in STD patients
and 2.5 percent in women attending antenatal clinics.
- Certain
regions, such as eastern India (Calcutta area) and northern
India (New Delhi region), still show a lower prevalence of HIV
(1 to 2 percent) among sex workers.
- Contrary
to traditional belief, sexually transmitted diseases and sex
with multiple partners are common in the country, both in urban
and rural areas. An estimated 3 to 4 percent of some rural populations
have a sexually transmitted disease.
- Injecting
drug use is a problem in Manipur, which is in North East region,
where 55 percent of drug users are HIV-infected and 1 percent
of women attending antenatal clinics are infected with HIV.
- HIV is
rapidly spreading to rural areas through migrant workers and
truck drivers. Surveys show that 5 to 10 percent of some truck
drivers in the country are infected with HIV.
- An estimated
1 to 2 million cases of tuberculosis occur in India every year.
In Bombay 10 percent of the patients presenting with tuberculosis
are HIV-positive. Tuberculosis is the presenting symptom of
AIDS in over 60 percent of AIDS cases.
- A major
international and governmental effort is necessary to respond
effectively to this severe epidemic.
In Cambodia
the HIV/AIDS data indicate that the current extensive HIV epidemic
started during the late 1980s or early 1990s and is predominantly
occurring among heterosexuals with multiple sex partners. To date,
there has been no evidence of a significant problem of injecting
drugs in Cambodia. Levels among blood donors in Phnom Penh have
risen from less than 0.1 percent in 1991 to about 10 percent in
1995. Dramatic rises have also been seen in sex workers, the police,
the military, STD patients and pregnant women.
The epidemic
in Myanmar is one of the most serious in the region. There are
an estimated half a million people with HIV in this country in
1996. The epidemic began with the infection of large numbers of
injecting drug users in the late 1980s, with a prevalence of 60
to 70 percent since 1992. HIV prevalence in sex workers has steadily
risen from 4.3 percent in March 1992 to 18 percent in March 1995.
There is substantial geographic variability, with infection rates
in pregnant women varying according to region between 0 and 12
percent in 1993. High levels of other STDs, low levels of condom
use, the clandestine nature of commercial sex, and limited blood
screening due to cost constraints are contributing factors to
HIV spread.
In Malaysia,
HIV infection levels in IDUs have grown rapidly from 0.1 percent
in 1988 to 20 percent in 1994. In female sex workers, rates have
gone from 0.3 percent in 1989 to 10 percent in 1994. A behavioral
study conducted nationwide in 1992 found that almost one in three
sexually active men and one in ten married men reported having
had casual sexual contact in the previous month. Reported condom
use in commercial sex is low. This implies serious potential for
heterosexual transmission. The rapid growth in prevalence in IDUs
and sex workers in Malaysia in the last three years is similar
to that seen in Thailand and Myanmar in the early stages of their
epidemics.
In Vietnam
there is some evidence that the HIV epidemic is now growing rapidly.
High levels have been demonstrated in IDUs in treatment (32 percent
in 1992-95), and recent evidence suggests increasing levels among
young men and women in the south of Vietnam. Rates in some sex
worker populations rose from 9 to 38 percent between 1992 and
1994-95.
In China the
majority (about 70 percent) of reported HIV infections and AIDS
cases have been among IDUs in Yunnan Province. HIV infections
are believed to be increasing among heterosexual populations in
southern China, especially in the areas surrounding Hong Kong.
The Chinese Academy of Preventive Medicine has estimated that
there were 10,000 HIV-infected persons in China as of the end
of 1993, growing to 100,000 by the end of 1995.
Limited HIV/AIDS
data for Laos suggest that HIV transmission may be starting in
the heterosexual population. Additional data are needed to confirm
the beginning of an HIV epidemic in Laos.
In Bangladesh,
Indonesia, Nepal and Sri Lanka the situation must be assessed
based upon relatively limited testing, low rates of HIV detection
in most populations, and low numbers of reported HIV and AIDS
cases. These limits to our knowledge of the situation make any
estimates of total prevalence or incidence quite speculative.
However, most of these countries appear to have high levels of
other STDs in their populations, implying a strong potential for
extensive HIV spread.
In Hong Kong,
Japan, Mongolia and the Republic of Korea, extensive spread has
not been documented. In DPR Korea and Bhutan no AIDS cases or
HIV infections have been reported, but only limited surveillance
has been carried out.
In the Philippines
there appears to be slower growth of the epidemic, with much lower
levels (less than 1 percent) of HIV among sex workers. Early AIDS
cases indicated some spread of HIV among men having sex with men.
The lower number of clients and more indirect nature of sex work
in the Philippines may help to explain the more gradual evolution
of the situation.
In Singapore,
infection levels in sex workers have been growing quite slowly.
The rapid growth of HIV infection in sex workers seen elsewhere
in the region has not been seen there, perhaps as a result of
prevention efforts.
Populations
Affected
The epidemics
in Asia are predominantly spreading through heterosexual contact.
On a regional basis, infected men probably outnumber infected
women by a factor of 3 to 1 or more, since commercial sex clients,
injecting drug users and men having sex with men have contributed
most strongly to the rapid initial growth of the epidemic. This
male/female ratio is expected to drop as the epidemic spreads
into the general population through spread of HIV from clients
of sex workers to their regular partners and spouses.
The HIV/AIDS
epidemics in Asian countries have been strongly influenced by
gender inequality and the frequent practice of men visiting sex
workers. Since sexual expression for females is typically more
limited than for males, the small population of sex workers has
large numbers of clients, and consequently high rates of other
STDs, which enhance HIV transmission. As a result, most epidemics
begin with rapid prevalence increases in sex workers and their
clients (as seen through STD clinic data). This growth can be
quite explosive. Annual incidences in sex workers as high as 25
percent and in clients of almost 10 percent have been seen in
India. High growth rates have also been well documented in numerous
studies in Thailand and Cambodia.
Sharing of
needles among injecting drug users, given its high efficacy for
HIV transmission, has also played a significant role early in
the epidemics, particularly in the Golden Triangle region (from
Thailand and Vietnam, across southern China, to Myanmar, to Manipur)
and in northern Malaysia. As the epidemics mature, transmission
from sex worker clients and IDUs to their wives or girlfriends
becomes the most important route of female infection, although
this transmission occurs at slower rates than that between sex
worker and client.
The ultimate
size to which the epidemic might grow in most countries is difficult
to assess because few studies of risk behaviors in the general
population are available. Only Hong Kong, Malaysia, the Philippines,
Singapore and Thailand have done national studies of risk behavior.
Indicating that the total number of men engaging in sexual risk
behavior is lower in Hong Kong, the Philippines and Singapore
than in Thailand and Malaysia, these studies may help to explain
the slower growth of the epidemic in those countries.
Pediatric
HIV infection is also difficult to assess in this region, given
the wide geographic variability in antenatal clinic infection
levels. In Thailand it is now estimated that 6,400 children are
infected annually, approximately 10 percent of total new HIV infections.
Impact
of Prevention Programs
The extent
of behavior change in the region has varied greatly from country
to country. Thailand has best documented the most extensive behavioral
change, the result of an active multi-sectoral national effort.
In national surveys conducted in 1990 and 1993, the percentage
of men visiting sex workers in the last year declined from 22
percent to 10 percent. Condom use in commercial sex transactions
is now the norm. As a consequence of these behavioral changes
STD rates have fallen precipitously, with reported cases dropping
to one-fourth of their initial levels. Male HIV incidence is estimated
to have fallen by an even greater factor. While there has been
substantial success of HIV prevention in commercial sex trade,
the situation in non-commercial casual sex remains of concern.
Current levels of condom use between boyfriend/girlfriend or with
other longer-term partners remains low, on the order of 10 percent.
Another area in which there has been only limited success has
been slowing HIV transmission within HIV-discordant married couples
in which the husband is HIV-infected and the wife is not. As these
women become infected, rates found in antenatal clinics continue
to climb.
The extent
of behavior change in the region has varied greatly from country
to country. Thailand has best documented the most extensive behavioral
change, the result of an active multi-sectoral national effort.
In national surveys conducted in 1990 and 1993, the percentage
of men visiting sex workers in the last year declined from 22
percent to 10 percent. Condom use in commercial sex transactions
is now the norm. As a consequence of these behavioral changes
STD rates have fallen precipitously, with reported cases dropping
to one-fourth of their initial levels. Male HIV incidence is estimated
to have fallen by an even greater factor. While there has been
substantial success of HIV prevention in commercial sex trade,
the situation in non-commercial casual sex remains of concern.
Current levels of condom use between boyfriend/girlfriend or with
other longer-term partners remains low, on the order of 10 percent.
Another area in which there has been only limited success has
been slowing HIV transmission within HIV-discordant married couples
in which the husband is HIV-infected and the wife is not. As these
women become infected, rates found in antenatal clinics continue
to climb. The slow growth of the epidemic in Singapore may largely
be attributable to general awareness and programs promoting condom
use at STD clinics and in brothels. It is reported that condom
use by sex workers has reached fairly high levels, although commercial
sex by Singapore residents traveling overseas remains an important
avenue of HIV transmission.
Efforts to
produce behavior change have been less effective in other countries
of the region. In India, no formal studies have been done on the
large-scale impact of prevention programs. From focus group discussions,
however, it appears that fear of acquiring HIV has risen among
the educated and the higher socioeconomic classes. This may lead
to higher condom use in these populations, but this is not yet
documented. Unfortunately, in the lower socioeconomic classes
and rural areas there is still a gross lack of awareness and knowledge
of HIV prevention methods, suggesting that behavioral change has
probably been minimal. There still appears to be low use of condoms
in many sex worker populations, especially among those who have
many clients per day. Condoms continue to be the exception rather
than the rule for most premarital and extramarital sex in India.
Sexually transmitted diseases continue to be a major problem in
this country, a fact not well recognized prior to the HIV epidemic.
In the Philippines,
behavioral surveys in 1990 and 1994 in Metro Manila have shown
fairly constant levels of casual and commercial sex, implying
little behavioral change during that time. The levels of condom
use, while rising somewhat in Metro Manila, remain quite low.
STD rates are lower than in many other countries of the region,
but as mentioned earlier, are high in certain populations, including
sex workers.
Myanmar and
Malaysia’s effectiveness in inducing behavioral change is difficult
to evaluate because no periodically collected data on risks is
available there. However, extensive NGO efforts in Malaysia and
grass-roots efforts in Myanmar may be reducing risk behaviors
and increasing the use of condoms.
For those
countries in the early stages of HIV epidemics (e.g., Bangladesh,
Bhutan, Brunei Darussalam, Indonesia, Nepal, the Maldives and
Sri Lanka), national efforts at HIV control have been fairly limited
and major nationwide behavioral change is unlikely to have yet
occurred. Non-governmental organization and governmental program
efforts targeted at commercial sex may have raised condom use
somewhat in more heavily populated urban settings, e.g., Jakarta,
Kathmandu and Colombo.
Impact
of Care Programs
Because the
epidemics in the region are comparatively young, many doctors
fail to properly diagnose AIDS and, in addition, medical care
is often difficult to access or limited in scope. As a result,
what little data are available on issues of survival and the effect
of care show somewhat shorter survival after diagnosis with AIDS
than in the industrialized world. In one study in Thailand, median
survival time after a diagnosis of AIDS was only 7 months, much
shorter than in many industrialized countries, possibly because
cases were only diagnosed when illness was quite advanced. In
the Philippines, a small study following HIV-infected sex workers
found survival times of one and a half years after the recognition
that the immune system was seriously compromised. In Thailand,
approximately one-fifth of children infected at birth were found
to have developed AIDS after 6 months. However, the findings of
these small preliminary studies can hardly be generalized. Studies
of accessibility to and use of care, and its impacts on disease
progression and survival are urgently needed throughout the region.
AIDS:
the Eruption in Asia
It is critical
to recognize the sheer numbers of people living in South and Southeast
Asia, a region that contains more than 60 percent of the world’s
adult population. In particular the evidence gathered in India
suggests rapid, extensive and uncontrolled spread in many parts
of the country. There is an urgent need for a comprehensive synthesis
of the state of the epidemic in India. It is clear that there
is a critical need, in this country as elsewhere in the region,
to gather more credible HIV/AIDS data on rural populations.
China, too,
because of its size and rapid changes in social and sexual behaviors,
potentially represents a major focus of the epidemic in the region.
The different
rates of spread within and between countries must be acknowledged
and better understood. For example, why is the spread of HIV in
the Philippines and Indonesia apparently slower than in Malaysia
and Thailand? Is it related to later introduction of the virus,
to lack of reliable information or differences in behavior?
Some governments
(Hong Kong, Malaysia, Singapore, Thailand) have committed extensive
resources to responding to the epidemic. However, the majority
of governments in the region are relying heavily on external financial
support to prevent epidemics occurring within their own borders.
In addition, there continues to be a serious problem of denial
and reticence about releasing surveillance and behavioral information
by some governments in this region.
Latin America
And The Caribbean
Latin America
and the Caribbean region is heterogeneous and diverse, with a
total of 44 countries and territories, an estimated population
of 470 million people with a variety of ethnic backgrounds, and
four main languages (English, Spanish, French and Portuguese).
The rate of spread of HIV/AIDS has been slower than in other developing
regions of the world, but the pandemic is well established and
there is a wide variation in the level of HIV infection and the
speed of the many epidemics among sub-regions and countries.
The dominant
modes of transmission vary from one country to the next, ranging
from some epidemics that are predominantly related to homo- and
bisexual behaviors, to epidemics connected to injecting drug use,
and to others that are primarily determined by heterosexual transmission.
In spite of this epidemiological diversity, sexual transmission
of HIV/AIDS accounts for 80 percent of overall transmission in
the region, ranging from 64 percent in Brazil to as high as 93
percent in the Andean sub-region (Bolivia, Colombia, Ecuador,
Peru, Venezuela). Although data are limited and sometimes spotty,
they reflect an increasing pandemic that is progressively affecting
heterosexual populations and non-urban areas.
As of June
10, 1996, Latin America and the Caribbean accounted for 26 percent
(176,930) of the cumulative total of cases reported in the Americas
to the Pan American Health Organization (PAHO) and 13.4 percent
of the cases reported worldwide to the World Health Organization
(WHO). It is estimated that 1.6 million people in the region have
already been infected with HIV and that some countries are at
particular risk of rapid dissemination of HIV from traditional
"at-risk" groups (sex workers, men who have sex with men [MSM],
men with multiple partners) and to other vulnerable groups in
the general population (women, youth and children).
Sexual behaviors
across the region reflect patterns that place the population at
risk for HIV. These behaviors include early onset of sexual behavior,
cultural acceptability of multiple partners, especially for males,
and low levels of condom use. In this region, however, despite
the relatively high proporation of men who have sex with other
men, patterns of homo- and bi-sexual behavior are still poorly
understood. Bisexual behavior is more prevalent than exclusively
homosexual behavior, while self-identification with a gay lifestyle
or culture is not common. Consequently, targeting messages likely
to reach MSM is difficult.
The current
epidemiological profile of HIV/AIDS in Latin America and the Caribbean
is driven by high-risk situations favorable to a rapid spread
of the HIV infection. Slowly but steadily the pandemic is taking
hold of communities rendered doubly vulnerable due to their socioeconomic
disadvantage and lack of information. Migration, both between
countries and from rural to urban areas, contributes to the continued
spread of HIV/AIDS and creates additional challenges to HIV prevention.
The epidemiological evidence signals a rapid shift of new infections
to younger ages, particularly toward people between 15 and 24
years old. In addition, there are marked tendencies for HIV infection
to increase among the general population and among specific populations,
in particular women, children, the poor, rural communities and,
generally, those who have lower socioeconomic status and those
who lack access to basic educational and health services.
Mexico,
The Isthmus of Central America and the Latin Caribbean
The number
of new HIV infections in Mexico, the Central American Isthmus
(Guatemala, Belize, El Salvador, Honduras, Nicaragua, Costa Rica
and Panama) and the Latin Caribbean (Cuba, Dominican Republic,
Haiti and Puerto Rico) continues to rise. As of June 10, 1996,
60,564 cases were reported to PAHO. This represents 8.7 percent
of the total number of cases reported for the Americas and 4.6
percent of the cases reported worldwide to WHO. However, the estimated
"true" incidence of AIDS is substantially higher than the number
of cases reported by 20 to 70 percent, with a one- to two-year
lag in data collection.
There is evidence
of continued increasing HIV incidence among MSM in Mexico, although
the rise is not as rapid as it was in the 1980s. Transfusion-associated
HIV infection and AIDS cases have drastically declined in this
country as in the rest of the region due to effective blood screening.
In Mexico this has resulted in an apparent slowing of AIDS cases
among women, but there is, in fact, a much younger epidemic of
heterosexually acquired HIV infection emerging among women. Consequently,
in this country two epidemics are observed: an urban epidemic,
more mature and affecting predominantly MSM and an emerging rural
epidemic, which is predominantly spreading through heterosexual
transmission.
The Central
American Isthmus and the Latin Caribbean reflect epidemics with
increasing HIV/AIDS incidence and accelerated heterosexual transmission.
Honduras accounts for 57 percent of AIDS cases diagnosed in Central
America, while it has only 17 percent of its population.
HIV seroprevalence
levels among sex workers in Honduras have reached as high as nearly
40 percent. Sentinel surveillance of pregnant women in the city
of San Pedro Sula has documented prevalence of up to 4 percent.
Commerce, migration patterns and communication within this sub-region
suggest that HIV is spreading within each country in well-established
local epidemics and, externally, across international borders.
In the Latin
Caribbean, Haiti is of particular importance because, perhaps
alone in the region, it represents a case of a relatively mature
epidemic. Due to social, economic and political instability, among
other factors, HIV prevalence rose from 2 percent in 1989 to an
estimated 5 percent of the adult population in rural areas in
1994. In urban areas the prevalence was estimated at 10 percent
in 1994. HIV prevalence is particularly high among sex workers,
STD clinic attendees and tuberculosis (TB) patients. High rates
of HIV prevalence found by recent studies among pregnant women
aged 14 to 24 are of particular concern.
Within this
sub-region, there is diversity in the structure and organization
of commercial sex, ranging from informal networks to thriving
sex industries. The latter involve countries from which sex workers
in other countries within and outside this region originate and
others that have organized sex tourism. In the Dominican Republic,
HIV seroprevalence among Dominican population subsets reached
levels up to 11 percent among sex workers, 5 to 8 percent among
STD patients and, by 1993, 1.2 percent among women attending antenatal
clinics. International and intra-regional travel, including tourism
and employment seeking, also exert major influences on the dynamics
of the epidemics in the Caribbean, enhancing the potential for
spread of HIV.
The
English-Speaking Caribbean
The predominant
mode of transmission for HIV in the English-speaking Caribbean
is heterosexual, but estimates of HIV transmitted through homo/bisexual
contacts account for 14 percent of all new infections. Inter-country
variation exists in AIDS incidence rates and in the underlying
HIV infection levels but, in general, the number of cases is increasing
in all countries. As of June 10, 1996, this region accounted for
4.6 percent (9,399) of the cumulative total of cases reported
in the Americas to PAHO and 0.7 percent of the cases reported
worldwide to WHO. The doubling time for the annual number of new
AIDS cases in this sub-region is four to five years. Some Caribbean
countries report AIDS incidence rates that are among the highest
in the world. Among the many small countries of the Caribbean,
the presence of countries with very high and very low rates of
HIV incidence indicates that there are many different epidemics
and not one regional pattern.
The male-to-female
ratio of incident AIDS cases has fallen dramatically over the
past 10 years, standing at just less than 2 men to 1 woman in
1994. Women aged 15 to 19 now have higher annual incidence rates
than men of the same age. Pediatric AIDS cases have been steadily
rising and now account for 5 percent of all incident cases. AIDS
has become the leading cause of death among young adult men in
some Caribbean countries. There is an urgent need for increased
surveillance of behavioral risk factors for AIDS and HIV infection,
although the small size of most Caribbean countries makes the
confidentiality issue an important obstacle to data collection
and analysis.
Among the
heterosexual population in the Caribbean, increasing numbers of
persons from marginalized groups are becoming infected, including
migrant workers, sex workers and users of crack cocaine. The extremely
low incidence of HIV infection through contaminated blood represents
a partial success story for the Caribbean region. Available data
from sentinel surveillance indicates increasing HIV prevalence
rates among pregnant women, sex workers, applicants for visas
to the U.S. and migrant farm workers in some Caribbean countries.
South
America
The number
of HIV infections and AIDS cases in South America is rising steadily.
As of June 10, 1996, South America accounted for 15.5 percent
(106,841) of the cumulative total of cases reported in the Americas
to PAHO and 8.2 percent of the cases reported worldwide to WHO.
However, as in other sub-regions, the true incidence of AIDS is
believed to be substantially higher due to under reporting and
difficulties in data collection. Within this specific region,
Brazil accounts for 75 percent of all cases of AIDS reported to
PAHO/WHO, followed by the Andean Region (15 percent) and the Southern
Cone (10 percent). Sexual transmission of HIV accounts for 74
percent of all reported AIDS cases (51 percent homo/bisexual and
23 percent heterosexual), injecting drug use for 19 percent and
blood and vertical transmission and undocumented cases, 7 percent.
The HIV/AIDS
epidemics in the region are at differing levels of maturity, but
are well established in most countries. There is considerable
transmission of HIV/AIDS due to injecting drug use in Brazil (27
percent) and the Southern Cone countries of Chile, Argentina,
Uruguay and Paraguay (30 percent), although recent data in Brazil
suggests that the HIV transmission through injecting drug use
seems to be leveling off. The pandemic in this region has progressed
since the early 1980s from one predominated by homo/bisexual transmission
to one with accelerated heterosexual transmission. In addition,
there is an emerging transition from epidemics centered in major
urban areas to increasing involvement of smaller urban centers
and rural areas. Epidemics are increasingly taking hold in specific
population subsets, including adolescents, marginalized communities,
and others characterized by low socioeconomic status and lack
of basic socioeconomic, educational and health services.
High HIV seroprevalence
levels have been reported among specific South American populations:
27 percent among sex workers in Santos City, Brazil; 30 to 60
percent in several studies of urban IDUs in Brazil and Argentina,
23 percent in MSM in Rio de Janeiro, and 1 percent to 3 percent
among pregnant women in Santos City, Brazil. The impact of HIV/AIDS
on morbidity and mortality is already seen in major urban centers
in Latin America and the Caribbean. In the city of São Paulo,
Brazil, for example, AIDS deaths are now the leading cause of
mortality in women of reproductive age.
Challenges
for Prevention
A significant
increase in knowledge, attitudes, practices and behaviors (KABP)
about HIV/AIDS has occurred in the region in the past ten years.
Behavior changes are most visible among sex workers, MSM and health
care providers involved in AIDS management. The behavior changes
observed invariably coincide with prevention interventions. However,
in spite of these trends, knowledge of the relationship between
HIV and AIDS and of asymptomatic transmission is still very limited
in the region as a whole. Knowledge of sexually transmitted diseases
and their relationship to HIV is limited, too. This is further
compounded by the fact that although awareness of HIV/AIDS has
substantially increased to levels over 80 percent in many countries,
there are still many misconceptions regarding the transmission
of HIV through casual contact. Surveys on knowledge, attitudes,
practices and behavior (KAPB) have documented the coexistence
of high levels of knowledge of HIV/AIDS in many populations with
myths and misconceptions, unsafe practices and low self-perception
of risk.
Immediate
and targeted attention to specific population subsets (women,
adolescents and children) is needed as these populations are expected
to become most vulnerable in the next phase of the epidemic. While
attention has been given effectively to partner reduction, non-penetrative
sex, and the increase and correct use of condoms, programs have
not fully capitalized on and need to be complemented with realistic
prevention messages addressing abstinence, delayed sexual initiation
and monogamy.
In brief,
as the pandemic escalates in Latin America and the Caribbean,
affecting larger segments of the population, the social, economic
and demographic impacts of HIV/AIDS are likely to exacerbate the
burden on individuals, communities and countries, threatening
the development and stability of the region as a whole. Hence,
the need for continued and increased support and an expansion
of HIV/AIDS prevention and control programs is critical to effectively
combat the pandemic in this region.
North
America
The growth
of the AIDS epidemic in North America has slowed in recent years
and is approaching stable incidence, largely due to the decline
in sexual transmission between men. However, current AIDS incidence
is at an unacceptably high level and it must be recognized that
this leveling off should in no way be considered reason for complacency.
AIDS data do not reflect current HIV infections, and HIV infection
continues to occur at an alarming rate in a number of sub-populations
and geographic areas. The characteristics of persons with HIV
infection and AIDS continue to change, reflecting the evolving
patterns of transmission.
Populations
Affected
Estimates
from a statistical model show that in 1992 in the United States
about 750,000 persons were living with HIV, and that year about
60,000 persons became infected with HIV. In Canada an estimated
34,000 adults were living with HIV in 1994, and 2,500 to 3,000
persons were newly infected with HIV each year in the period from
1990 to 1994. Recent estimates based on surveys of childbearing
women indicate that approximately 3.2 per 10,000 children born
in Canada and 15.1 per 10,000 children born in the United States
carried HIV antibodies. In the U.S., an estimated 12,000 children
are currently living with HIV. Since the start of the epidemic,
from 1 to 1.5 million cumulative HIV infections have occurred
in North America.
HIV infection
has become one of the major causes of death for individuals between
the ages of 25 and 44. Among men in this age group, it was the
leading cause of death in the U.S. and the second leading cause
of death in Canada in 1994. In that same year, HIV infection was
the third leading cause of death among 25- to 44-year-old women
in the U.S.
Through December
1995, 513,486 persons had been reported with AIDS in the United
States; 13,291 had been reported through March 31, 1996 in Canada.
Overall AIDS incidence in North America has been slowing progressively.
Although there were large increases in the number of persons annually
diagnosed with AIDS-related opportunistic illnesses (AIDS-OIs)
through the early 1990s, the annual increase since 1993 has been
less than 5 percent. In 1995, after adjustment for delays in reporting,
approximately 62,000 persons were diagnosed with AIDS-OIs (29
per 100,000 population) in the United States and 2,166 in Canada
(9 per 100,000 population).
In North America,
although there has been an overall slowing in the increase in
AIDS incidence, there has been substantive variation in the populations
affected. For example, in the United States, the increase in AIDS
incidence in the 1990s has been greatest for women compared to
men, blacks and Hispanics compared to whites, and persons infected
through heterosexual contact compared to those infected through
other modes of transmission. As a result of these trends, AIDS
incidence in 1995 was 6.5 times greater for blacks and 4 times
greater for Hispanics than for whites, 20 percent of persons diagnosed
with AIDS were women, and 15 percent were infected heterosexually.
The HIV infection
rates are also high among certain groups, such as incarcerated
persons. In 1994, 2.3 percent of nearly 1 million prisoners in
the United States were known to be infected with HIV, the rate
of AIDS among prisoners was 7 times the rate of the non-incarcerated
population, and AIDS was the second leading cause of death among
prisoners. Among Canadian prisoners, HIV prevalence is higher
in women, between 2 and 10 percent versus 1 to 4 percent for men;
for both sexes, transmission is primarily related to injecting
drug use.
In the United
States, AIDS incidence among children less than 13 years of age
has declined annually. For example, while there were 938 cases
in 1992, there were approximately 600 cases in 1995. Only 21 Canadian
children were diagnosed with AIDS in 1995. This decline may well
reflect such factors as lower conception rates in women diagnosed
with HIV and the possible impact of maternal and neonatal zidovudine
therapy on HIV transmission.
In North America,
syphilis incidence has declined, yet 1994 rates in the U.S. were
60 times greater for blacks than for whites. The incidence of
gonorrhea has also declined. In 1994, the U.S. rate was 168 per
100,000 and the Canadian rate was 21 per 100,000.
Estimates
from statistical models and data from several cohort studies demonstrate
that HIV transmission among men who have sex with men (MSM) has
declined from the very high levels of the early 1980s. In Canada,
HIV incidence among MSM has dropped from about 5 to 10 percent
per year in the early 1980s to an estimated 1 to 2 percent per
year in the early 1990s. The HIV seroprevalence rate among MSM
attending STD clinics in the U.S. fell from over 30 percent in
the late 1980s to 24 percent in 1995. However, the prevalence
of HIV infection among MSM remains high in almost all areas of
North America.
The declining
trends in HIV infection and morbidity among MSM are consistent
with trends in STD surveillance data, which show large decreases
in the rates of syphilis and rectal gonorrhea. These declines
are also consistent with behavioral survey results, which show
decreases in the number of sexual partners and other indicators
of sexual risk behaviors. There does, however, appear to be some
variation in the risk behaviors of younger MSM in that relatively
high rates of unprotected receptive anal intercourse (30 percent
to 47 percent over a 6- to 18-month period) continue to be reported
by this age group.
In the United
States, HIV prevalence among injecting drug users has decreased
in all areas. The largest decrease has been observed in the northeast
among IDUs in drug treatment programs. Anonymous testing in drug
treatment centers in 29 U.S. cities from 1988 to 1995 showed higher
HIV infection rates in the northeast (median HIV prevalence, 23
percent) and lower in the west (median, 1.5 percent). AIDS cases
related to injecting drug use has increased less than 5 percent
annually since 1993. In 1995, more than three-quarters of the
injecting drug users diagnosed with AIDS were black or Hispanic
and one quarter were women. In Canada, HIV infection among IDUs
is a major concern. For example, incidence in Montreal is currently
estimated to be 5 per 100 person years; this rate is among the
highest in North America.
Although some
studies have shown a decrease in both unsafe injection practices
and HIV incidence, new HIV infections continue to occur and the
number of IDUs sharing injection equipment is high. Several studies
have shown that 48 to 88 percent of IDUs continue to share injection
equipment and that only 22 to 63 percent clean this equipment
in any way. In Canada, sterile injection equipment for persons
who continue to inject drugs is available in pharmacies and through
numerous needle-exchange programs. In contrast, 45 of the 50 states
in the United States prohibit the sale or possession of sterile
needles or syringes without a medical prescription, and only a
small number of legal needle exchange programs exist.
AIDS cases
related to heterosexual contact represent an increasing proportion
of cases in North America. Heterosexual contact is the most common
mode of transmission among women diagnosed with AIDS in the U.S.,
and has doubled as a proportion of female AIDS cases in Canada
since 1991. While a large proportion of these cases reported sexual
contact with an IDU, a substantial proportion of women who acquired
their infection heterosexually were unaware of their partner’s
risk status. In addition to injection drug use, the use of crack
cocaine in the United States has been associated with an increased
risk of HIV transmission through sexual contact in both urban
areas and the rural South.
Between 1990
and 1995, the average HIV prevalence among heterosexual men and
women attending STD clinics in North America changed little. However,
the seroprevalence rates of heterosexual men and women in New
York, Miami and Washington, DC, grew by 5 percent or more.
Changes
in Behavior
General population
surveys have shown that the level of HIV/AIDs knowledge is high
in North America and that changes in sexual behavior have occurred.
Among adolescents in U.S. schools, the use of condoms reported
at last sexual intercourse increased from 46 percent in 1991 to
54 percent in 1995. In 1992, 50 to 65 percent of Canadian adolescents
reported using a condom at last sexual intercourse. A study conducted
in the U.S. from 1988 to 1991 showed that condom use by heterosexual
adults with non-steady partners increased from 14 percent to 22
percent among whites and from 5 percent to 27 percent among blacks.
In a 1994 Canadian survey, 26 percent of men and 19 percent of
women aged 20 to 45 reported using condoms with non-steady partners.
Europe
The European
region counts some 850 millions inhabitants living in 50 countries.
For the purpose of this analysis, this region also includes countries
of central Asia that have geo-political affinities with countries
in eastern Europe. The analysis of the European AIDS epidemic
reveals complex patterns and dynamics that cannot be reduced to
a simple division between eastern and western Europe. However,
this report uses the old political division because there are
large differences in the timing and spread of the epidemic between
eastern and western Europe, and the dramatic changes occurring
in central and eastern Europe create specific situations of high
vulnerability.
Long-Term
Trends from AIDS Surveillance
By the end
of 1995 a cumulative total of 160,982 AIDS cases, including 154,
866 adult/adolescent cases and 6,060 pediatric cases, had been
reported in the region. A total of 26,139 new AIDS cases were
reported in 1995, an increase of less than 1 percent over the
25,986 cases reported in 1994.
Over the past
2 to 3 years, AIDS incidence appears to have stabilized in several
countries in northwestern Europe. In contrast, there is no indication
of the AIDS epidemic leveling off in countries in southwestern
Europe.
In central
and eastern Europe (with the exception of Romania) and central
Asia, the HIV/AIDS epidemic is much more recent and AIDS incidence
much lower than in western Europe. The highest rate per million
(9.9) was found in the federal Republic of Yugoslavia in 1995.
However, in some countries, a rapid spread of HIV is indicated,
which is mainly linked with injecting drug use. In Poland and
the Federal Republic of Yugoslavia (Serbia and Montenegro), where
injecting drug users account for the largest proportion of cases,
the incidence of AIDS is rising rapidly.
Before 1990,
most AIDS cases were diagnosed in men who have sex with men. Since
1990, however, IDUs account for the highest proportion of yearly
diagnosed cases in the region (43 percent of adult and adolescent
cases in 1995). Among the 22,494 cumulative heterosexual AIDS
cases diagnosed up to December 1995, persons originating from
other regions accounted for 30 percent. The shift in transmission
patterns was accompanied by an increase in the proportion of female
cases, which rose from 11 percent in 1986 to 20 percent in 1995.
Most women diagnosed with AIDS in 1995 were IDUs (46 percent)
or had been heterosexually infected (40 percent), often by an
IDU sex partner (accounting for 33 percent of non-IDU heterosexually
infected women).
The epidemic
among children is closely related to that among women. In most
countries, the vast majority of children have been infected through
mother-to-child transmission. However, in the region as a whole,
the epidemic among children is dominated by the epidemic in Romanian
hospitals, which was detected in 1989 and accounts for over 50
percent of the 6,060 pediatric cases reported in the European
region. Another, though much smaller, epidemic among children
in hospitals occurred in the Russian Federation in the late 1980s.
HIV Incidencs
and Prevalence
In western
European countries, reconstruction of past trends of HIV incidence
through back calculation models usually shows that the incidence
of HIV infection peaked in the mid-1980s. The same method shows
a low but steady increase of HIV prevalence among heterosexual
populations. Trends for IDUs appear more variable and complex.
Birth cohort analysis of AIDS cases suggest that HIV transmission
through injecting drug use among young adults decreased in the
early 1990s in France, Italy and Switzerland, but increased over
the same period in Spain and Portugal.
Among eastern
European countries, large outbreaks of HIV infection in IDUs have
been observed in the late 1980s in the former Republic of Yugoslavia
and Poland. Until recently, HIV reporting systems associated with
systematic testing of large segments of the general population
had not identified increasing trends of HIV incidence. However,
Ukraine recently reported a dramatic increase of newly infected
IDUs in cities bordering the Black Sea. For example, the percentage
of HIV-infected IDUs in Nikolayev rose from 1.7 percent in January
1995 to 56.5 percent in December, eleven months later.
Back calculations
performed in western Europe in 1996 estimate that 450,000 adults
were living with HIV in western Europe at the end of 1993, a figure
similar to that obtained by adding national "best" estimates.
There is no indication of a rapid upward or downward trend in
these countries. An annual incidence of around 40,000 since the
beginning of the 1990s seems a plausible estimate. In many countries
of eastern Europe, which are at a very early stage of the AIDS
epidemic, estimates of HIV prevalence are more uncertain. Best
estimates, according to national surveillance systems, gave a
total of around 18,000 cumulative infections by the end of 1993.
The possibility of recent rapid increases in HIV incidence in
some of these countries, as demonstrated by the 1995 Ukraine outbreak,
makes any estimate of prevalence or incidence for 1995 extremely
hazardous.
In countries
where local data are available, the HIV prevalence in pregnant
women has been much higher in urban than in rural areas (England,
Scotland, Italy). The highest prevalence (between 1 and 4 per
thousand) is observed in women who give birth or in newborns in
the regions of Paris, Rome, Milan, London, Madrid, Barcelona and
Amsterdam. In northern and eastern Europe, where data are mostly
limited to the national level, the prevalence among pregnant women
appears much lower (between 0 and 0.1 per thousand). In 1995 systematic
screening for HIV did not detect any infection among women in
Bulgaria, Lithuania, Moldova, Norway or the Slovak Republic.
Rapid
Spread of STDs in Eastern Europe and of HIV in Ukraine
Even as western
Europe has experienced significant declines in the incidence of
syphilis and gonorrhea, there has been rapid rise of syphilis
reported in several countries in eastern Europe. From 1908 to
1991, the incidence of syphilis in western Europe dropped to below
2 per 100,000; it remained stable in Poland from 1986 to 1993,
but rose sharply in several Newly Independent States, starting
in 1989 (see Figure 4).
Countries
of the former Soviet Union have experienced dramatic increases
in the incidence of syphilis from a low 5 per 100,000 in 1990
to a high 170 per 100,000 in 1995. The sharp increase in syphilis
incidence prefigures the mounting vulnerability of the region
to the sexual transmission of HIV.
In Ukraine,
since the beginning of the HIV/AIDS epidemic in 1988, 40 to 80
new HIV infections were registered annually through extensive
testing for HIV in various population groups. During the last
year, however, more than 3,000 drug users have been found to be
HIV-infected in Ukraine. The vulnerability of this country to
the further spread of HIV is reflected in the more than tenfold
increase of the number of syphilis cases between 1991 and 1995
(see Figure 6).
A European
network of STD clinics from 17 countries (Czech Republic, Hungary,
Norway, Switzerland and countries of the European Union except
Luxembourg and Ireland) has collected data on HIV prevalence among
STD patients since 1990. Among the 87,640 patients tested, 2.8
percent were HIV-infected. MSM had the highest HIV infection rate
in most countries (between 30 and 50 percent in Denmark, France,
Germany, Portugal and Spain, and 10 percent or less in the Czech
Republic, Finland, Greece, Hungary, Norway, Scotland and Sweden).
In Italy, Spain and Switzerland, the highest rates of HIV infection
were found in IDUs.
Among the
heterosexual STD patients who were not IDUs, HIV rates were below
1 percent in 11 countries, 10 to 30 times lower than among MSM.
Higher rates (between 1 and 3 percent) were found in France, Germany,
Italy, Portugal, Spain and Switzerland. No significant HIV prevalence
trend has been observed in this population. Available results
from systematic screening of STD patients in several countries
in eastern Europe have shown very low rates of HIV infection.
In Russia, HIV infections were identified in only 64 of nearly
6 million tests done between January 1987 and December 1993. In
1995, 2.3 per 100,000 STD patients tested in Russia were identified
as infected with HIV. However, dramatic ongoing changes in STD
incidence in these countries demonstrate a potential for a rapid
change in HIV dynamics. Also in some countries of eastern Europe,
where STD incidence rates are relatively low (as for example in
Slovenia, where 2 early syphilis cases were reported per 100,000
population in 1995), HIV infections are already beginning to be
detected among STD patients. In one of the regions of Slovenia
that year, 1.4 percent of 294 STD patients tested unlinked anonymously
for surveillance purposes were found to be infected with HIV.
In some countries
in southwestern Europe the proportion of HIV-infected IDUs has
been high for years. In Madrid, between 59 and 74 percent of IDUs
entering drug treatment programs from 1986 to 1990 were found
to be infected with HIV. In Italy, on a national level, HIV prevalence
in IDUs was 31 percent and 39 percent in 1990 and 1991, respectively.
In Poland, on a national level, the percentage of HIV-infected
IDUs treated at health care settings ranged from 8.7 percent in
1988 to 2.9 percent in 1993. However, 46 percent of IDUs entering
two drug treatment centers in Warsaw in 1993 were reported to
be infected with HIV. In some eastern European countries, HIV
infection seems not yet to have been introduced, although injecting
drug use is on the rise and there is evidence of high-risk injecting
behavior. In Slovenia, 80 percent of IDUs interviewed outside
IDU treatment centers in 1991 admitted sharing injecting equipment
during the previous year, although none of 115 unlinked anonymously
tested IDUs entering methadone maintenance programs in two IDU
treatment centers in 1995 tested positive for HIV infection.
Changing
Behavior
In Europe,
the lack of basic data on sexual behavior in most countries means
that behavior change, condom availability and use are all difficult
to monitor. A review of behavioral surveys carried out in western
European countries between 1987 to 1990 shows that the reported
numbers of sexual partners remained quite stable irrespective
of the country, while condom use increased markedly, particularly
for the most sexually active populations. Among people with casual
partners, the percentage of those reporting using condoms regularly
rose from 8 percent in 1987 to 48 percent in 1989 in Switzerland,
and from 9 percent to 40 percent in the Netherlands during the
same period. In the United Kingdom, the percentage of 18- to 24-year-olds
who reported using a condom during their most recent sexual intercourse
rose from 14 percent in 1986 to 31 percent in 1989. Such results,
based on self-reported behaviors, are also partially supported
by trends in condom sales. In Switzerland, wholesalers (representing
80 percent of the market) increased their sales from 7.6 million
units in 1986 to 15 million in 1992. In France, the number of
condoms sold in pharmacies and supermarkets rose from 38.6 million
to 74.4 million between 1986 and 1993.
In contrast,
very little is known about the condom market in central and eastern
Europe. In Slovenia, condoms are available through pharmacies,
petrol stations and supermarkets. In some countries, condom availability
and low income levels can heavily restrict condom use. In Kazakhstan
in 1995, condoms were available only in some pharmacies of Almati,
the capital city. In Moscow that year, although condoms were available
at most pharmacies and also could be found in some commercial
kiosks, supermarkets and hotels, the price of a twelve-unit pack
represented nearly one-third of the minimum monthly salary.
The most worrisome
information coming from STD surveillance arose recently from the
independent republics of the former Soviet Union. Substantial
increases in syphilis rates have been seen since 1990 in several
of these states. In 1995, compared to 1994, syphilis incidence
rates per 100,0 00 population rose from 81.7 to 172 in Russia
(from 169.8 to 320.8 in St. Petersburg), from 72.1 to 147.1 in
Belarus, from 116.6 to 173.6 in Moldova, and from 32.6 to 123
in Kazakhstan. These results indicate not only the likelihood
of further spread of other STDs (including HIV infection), but
also a potential for further spread to neighboring countries.
This is already happening in Finland, where 118 new syphilis cases
were diagnosed in 1995, as compared with 63 in 1994. Investigations
have demonstrated close links between the Finnish and the Russian
epidemics, through the increase of Finnish business/pleasure tourism
in the St. Petersburg area, and migration from Russia to Finland.
Current
and Future Trends
Transmission
of HIV through injecting drug use has had and continues to play
a major role in the dynamics of the epidemic in the region. Such
transmission accounts for the majority of AIDS cases in some of
the western countries with highest incidence (Spain and Italy),
and is strongly associated with AIDS cases occurring among heterosexual
adults and among children in the same countries. The sharp rise
of AIDS incidence observed since 1992 in Portugal is mainly due
to a rapid increase of cases among IDUs. In eastern European countries,
the more serious HIV infection outbreaks reported until now (Poland
and Ukraine) are also associated with IDU.
The relative
proportion of homo/bisexual men among people with AIDS has steadily
decreased in the past ten years in the region. This is mainly
due to a comparatively rapid progression of cases among drug users
and to a low, but steady, increase in the proportion of heterosexual
AIDS cases. AIDS incidence among gay men appears to be moderately
declining or quite stable in most of western Europe, while still
increasing in Greece, Portugal and Norway. In the Baltic States,
Slovenia and Hungary, homosexual men account for the vast majority
of HIV infections reported so far among males. Homosexual men
represent 77 percent of the 171 HIV infections reported in Hungary
in the past 5 years. In Russia, male to male sex was considered
the mode of transmission in 53 percent of the 587 HIV/AIDS cases
reported among adult males up to December 1994. In Slovakia and
Slovenia, 1996 data from unlinked anonymous HIV serosurveys using
saliva tests performed in gay gathering places showed prevalence
rates of around 3 percent, indicating a potential for further
spread of the HIV epidemic in that population.
Moreover,
information from the United Kingdom indicates that the declining
trend of male-to-male transmission noted in the late 1980s may
have begun to reverse, starting in 1990. Although of great importance,
the relative increase of AIDS cases and HIV infections among non-injecting-drug
heterosexuals, should not mask the fact that homosexual men and
IDUs continue to experience the heaviest burden of the epidemic
throughout the European region.
North
And South Pacific
For the purpose
of this report, North and South Pacific is defined as Australia,
New Zealand, Papua New Guinea, the Territories and independent
island countries of the Pacific. Populations range from 18 million
people in Australia to less than 10,000 in some of the island
states. By the end of 1995, around 7,400 cases of AIDS had been
reported in North and South Pacific, of which over 7,000 were
in Australia and New Zealand.
Australia
and New Zealand’s experience of the HIV epidemic has paralleled
that of a number of industrialized countries, particularly those
of Northern Europe. The major pathway of transmission has been
through sexual contact between men, which occurred primarily in
the early 1980s. This pattern also has been reflected in the French
Territories of New Caledonia and French Polynesia. The HIV epidemic
in Papua New Guinea has developed more recently, mostly as a result
of heterosexual transmission. In a number of the small island
countries in the region, HIV and AIDS cases have been reported,
but populations and case numbers are really too small to define
any clear patterns of transmission.
Overall,
the per capita HIV prevalence and incidence of AIDS in Australia
and New Zealand has been roughly in the middle of the range observed
in industrialized countries in other regions of the world. Although
AIDS incidence so far has been low in Papua New Guinea, it was
estimated that by the end of 1994 there were 4,000 adults living
with HIV infection in Papua New Guinea, overtaking Australia on
a per-capita basis to give the highest prevalence in the North
and South Pacific region. Some of the smaller countries of the
region have relatively high rates, even though the number of reported
cases is small.
Populations
Affected
Cumulatively,
over 85 percent of HIV infections in Australia and New Zealand
are reported to have been acquired through sexual contact between
men. In New Caledonia and French Polynesia, around two-thirds
of cases with a reported mode of transmission were in men with
a history of homosexual contact. Back-projection estimates from
AIDS cases in Australia show that there was a peak in the homosexual
transmission of HIV infection between men in the early to mid-1980s
and a substantial decline in transmission rates during the latter
half of the 1980s.
The incidence
of AIDS has reached a plateau in Australia and actually appears
to be declining in New Zealand. These patterns are essentially
due to the drop in the rate of sexual transmission of HIV infection
between men that occurred ten years earlier. This decline began
well before any organized prevention program was implemented,
but is likely to have been supported through the strong partnerships
developed between gay community-based organizations and governments.
Current trends in sexual transmission between men are unclear.
Cohort studies, behavioral surveys and monitoring of rectal gonorrhea
provide a basis for assessing changes in HIV risk.
In Australia
and New Zealand, HIV has remained rare among people who inject
drugs, apart from men who also have homosexual contact. In heterosexual
injecting drug users, surveys have consistently found HIV prevalence
below 2 percent. Both countries have adopted harm reduction policies,
including extensive use of needle exchange. Although the low HIV
rates indicate successful prevention efforts in this population,
the transmission of hepatitis C continues to occur at epidemic
levels among injecting drug users, with annual incidence rates
of 15 to 20 percent being recorded in Australia. The ongoing hepatitis
C epidemic indicates the continuing potential for a substantial
outbreak of HIV through blood contact among injecting drug users.
On the basis
of available evidence, heterosexual transmission of HIV has been
infrequent in Australia and New Zealand. The pattern appears to
be very different in Papua New Guinea, where heterosexual transmission
accounts for the largest proportion of diagnosed infections. By
the end of 1995, nearly 90 percent of the diagnosed cases of HIV
in Papua New Guinea for which modes of transmission had been reported
were attributed to heterosexual contact, and an equal number of
males and females had been diagnosed with HIV infection.
In Australia,
and to a lesser extent New Zealand, high rates of STDs other than
HIV in indigenous people have led to mounting concern about the
potential for a major heterosexual epidemic of HIV infection in
these populations. Surveillance data so far indicate that the
rate of HIV diagnosis is no higher among indigenous than non-indigenous
people, but in Australia the rate of HIV diagnosis has increased
in the past six years among indigenous people. In contrast, the
overall rate of HIV diagnosis in the Australian population has
declined substantially. There has also been a shift toward more
heterosexually transmitted infections among the diagnoses of HIV
among indigenous people in Australia.
Surveys among
men who have sex with men show a substantial decline in Australia
and New Zealand over the past decade in the frequency of unprotected
anal intercourse with casual male sexual partners. There have
also been major declines in the sharing of equipment by injecting
drug users. There has been little longitudinal information on
heterosexual risk behavior at a national level, but increased
condom use has been reported among heterosexual university students.
HIV Care
Most of the
need for HIV care in North and South Pacific has so far been in
Australia and New Zealand. In these countries, there has generally
been wide availability of good treatment services, access to appropriate
therapy and a steadily improving climate in regard to discrimination.
As the burden of HIV illness increases in Papua New Guinea and
possibly some of the other smaller countries of North and South
Pacific, it is likely that strain will be placed on existing health
infrastructures, as has been the case in other parts of the developing
world.
Symposium
Conclusions
1.Remarkable
progress has been achieved in reducing the spread of HIV in
some developing countries and in certain populations in industrialized
countries. Specifically, HIV incidence has declined in young
men in Thailand.
Impressive
declines in HIV incidence and/or prevalence have been reported
in gay men in the U.S., Australia, Canada and Western Europe.
A decline in prevalence has also been observed in young women
in Uganda, a country with one of the most mature HIV/AIDS epidemics.
HIV prevalence has remained low in injecting drug users in a
number of countries. In Australia, for example, major epidemics
have been prevented in injecting drug users through timely prevention
efforts. To a large extent, these successes in HIV reduction
are attributable to education and prevention programs.
2. The HIV
epidemic continues to expand in most developing countries, as
well as in those European countries undergoing political stress
and upheaval.
The social,
economic, demographic and health impacts of the HIV epidemics
are increasing in most countries. Especially dramatic is the
spread of HIV in young adults, adolescents and children in developing
countries. In a number of industrialized countries, the spread
of HIV is increasing rapidly in minority populations. There
is also continuing spread of HIV to rural areas throughout the
developing world. In many countries, the proportion of infected
women is now roughly equal to that of men. Globally, heterosexual
transmission continues to rise.
Extensive
commercial sex industries, high prevalence of sexually transmitted
diseases and injecting drug use provide the potential for explosive
epidemics in several countries, including Indonesia, China,
and several countries in West Africa and Eastern Europe. In
India, Cambodia and Myanmar, the explosion has already occurred.
3.The global
pandemic is now composed of multiple epidemics in different
stages of development. The characteristics of these epidemics
include different viruses (HIV-1 and HIV-2), different strains
of the same virus, differences in transmission modes and differences
in incidence in population subsets, including young adults.
HIV Subtypes
Background
- Advances
in genetic techmology in the 1980s made it possible to duplicate
in the test tube - by a technique called polumerase chain reaction
(PCR) - the RNA or DNA forms of the genetic "code" of HIV. This
revolutionary application made it possible to use the genetic
information to distinguish the two major types of HIV, type
1 (HIV-1) and type 2 (HIV-2), as well as different strains within
each type.
- HIV-1 is
more virulent than HIV-2 and is the predominant strain around
the world. To date, HIV-2 is found principally in West Africa,
and constitutes a small minority of infections in other parts
of Africa, South America and West India.
Applications
- As with
other typable infectious diseases, the ability to compare and
distinguish specific HIV virus isolates from individuals makes
it possible to track the spread of virus from person, country
to country and region to region.
- Surveillance
and knowledge about the geographic extent of HIV-1 strains is
important to confirm or rule out chains of transmission between
individuals and to provide clues as to how the epidemic is spreading.
Furthermore, the development and performance of AIDS vaccines
and clinical prognosis may be affected by biological differences
in the manifestations of infection with different subtypes.
HIV-1 and
HIV-2 Subtypes
- To date,
two major groups of HIV-1 exist, "M" and "O" (for outlier).
The virus that causes the great major of HIV-1 infections diagnosed
and studied in the world are in the M group. The O group includes
a small number of isolates discovered in Africa (with one case
found recently in the U.S.). These are genetically quite distant
from the M group, and consequently may not show up on some standard
laboratory tests for HIV-1.
- HIV-2 is
divided in the subtypes A and B, but further subtypes C through
E have recently been characterized by DNA sequencing.
Geographic
Distribution
- In the
predominant M group of HIV-1, 8 subtypes - A through H - have
been identified to date. Most all are found in one area or another
of Africa, while in other regions of the world, certains subtypes
predominate.
- In Europe,
subtype B is predominat in men who have sex with men, while
a variety of subtypes are found in the relatively small numbers
of people infected through heterosexual contact in Europe and
the countries of former Soviet Union. Subtype B has also been
noted in Indonesia, the Philippines and Taiwan.
- In India,
subtype C predominates, with a small number of A nad B infections.
In Thailand, E predominates, while a minority of B infections
occur in drug users, and this B strain has also been found in
drug users in Myanmar (Burma), Malaysia ans southeast China.
- In the
Americas (North, South and Central), as well as in Australia,
New Zealand and Japan, subtype B is most common. Subtype F occurs
in Romania, and along with subtype C also is found in a small
proportion of strains in Brazil.
Biological
Implications
- Preliminary
epidemiological work in Thailand suggests that subtype E may
be more transmissible by the sexual route than subtype B, while
preliminary clinical studies there suggested that subtype E
infection may produce significantly lower levels of CD4+ T-cells
than does infection with subtype B. Preliminary in vitro work
in the U.S. suggests that subtypes C and E may more readily
infect the Langerhans cells that line the sexual tract than
subtype B.
- It is not
known whether an AIDS vaccine designed against one subtype of
HIV-1 will work to protect the vaccine recipient against other
subtypes to which they may be exposed. Knowledge of which subtypes
exist in which proportions in specific geographic areas will
be important for designing AIDS vaccine trials and determining
which antigens might need to be included in future vaccines.
Simple economical techniques have been developed for collecting
HIV-1 in non-infectious dried blood spots that can be mailed
safely without refrigeration to laboratories capable of performing
PCR and subtyping.
Research
- Needs and
Implications Some countries have multiple subtypes circulating
in substantial numbers, such as E and B in Thailand, A and D
in Uganda, and B and C in South Africa. Prospective studies
among infected persons who continue to expose themselves to
HIV (e.g., sex workers and injecting drug users) would be useful
to determine whether infection with one subtype provides protection
against "superinfection" with another subtype. Recent data from
Senegal suggest that HIV-2 infection provides partial protection
from HIV-1 superinfection. If superinfection does not occur
as frequently as might be expected, this would bode well for
the possibility that killed, whole-virus or live, attenuated
vaccines might work if they can mimic the natural immune
response to HIV.
4. Epidemiological
surveillance is an essential early component of a country’s response
to HIV. In most developing countries and in Eastern Europe, surveillance
and evaluation data are insufficient to monitor adequately the
status and interpret the changes in trends of the HIV epidemics.
Recommendations
for Collection of HIV/AIDS Surveillance Information
As epidemics
of HIV and other sexually transmitted infections (STIs) continue
to evolve around the world, the need to understand more clearly
the dynamics of transmission, the impact of the epidemics and
the interventions designed to curtail them continues to grow.
It is necessary to recognize the gaps in our knowledge, reexamine
data needs, enhance the ability to interpret this information
and identify the most cost-effective methodologies for gathering
this data.
The guiding
principle of any surveillance system should be,"Are the data being
distributed and used by as broad a base of users as possible?"
The HIV/AIDS surveillance system established early in the epidemic
in Thailand proved invaluable, not only for the quality and scope
of the data generated, but, more importantly, because the ongoing
surveillance information became an integral part of the entire
national response to the epidemic. This was mainly due to the
widespread dissemination of the date as it was produced, which
served as a powerful tooi for raising the public profile of the
epidemic and refining program interventions.While the costs, protocols
and underlying infrastructure of the Thailand system may not be
suitable for all settings, the precedent of routine dissemination
of data should serve as an example for other national surveillance
systems.
In order to
improve our understanding of the epidemic, the following guidelines/principles
should be considered:
- Adopting
a minimum surveillance system for HIV/AIDS should be a key part
of an initial response for any country.
- There should
be more reliance on current HIV prevalence information (point
prevalence) and less use of cumulative HIV numbers (period prevalence)
which tend to mask the actual trends in the epidemic.
- AIDS case
reporting is extremely inaccurate in most of the developing
world. There is significant under-reporting, inconsistent use
of case definitions and, as a result, the number of reported
AIDS cases does not reflect the current status of the epidemic.
- There are
three main uses forAIDS case reporting:
- Estimating
retrospectively ("back estimating") the number of HIV infections
after adjustment for reporting delays and incomplete reporting;
- Estimating
AIDS mortality; and
- Determining
possible burden on the health care system as well as on
other aspects of society.
- Passive
reporting systems to garner AIDS case data are generally inexpensive
but more credible means of addressing the above issues. AIDS
case reporting continues to be a valuable aspect of a minimal
monitoring system. AIDS is still a powerful indicator of the
morbidity and mortality of this epidemic, particularly for policy
makers.When analyzed by age group over time, AIDS case analysis
may provide insight into trends occurring within younger age
groups.
- The goal
of a serial sentinel HIV seraprevalence system is to generate
a series of consistent prevalence data using a uniform methodology
that samples selected populations (women attending antenatal
clinics, sexually transmitted infection patients, sex workers,
etc.) within both rural and urban settings.
- Even when
credible serial H IV prevalence information is obtained for
various representative populations, interpretation is often
difficult It is necessary to collect information on a range
of additional issues. Special surveys should be utilized at
appropriate intervals linking HIV seroprevalence information
with:
- Behavior
change (e.g., number of sexual partners, condom use, history
of sexually transmitted infections);
- STI
prevalence in specific populations (e.g., sex workers, women
attending antenatai clinics);
- AIDS
morbidity and mortality (e.g., facilit:y-based surveys of
hospital bed utilization, use of such indicators as the
number of tuberculosis cases, other possible use of vital
statistics and funeral statistics);
- Fertility;
- Estimation
of "epidemic saturation" of vulnerable populations
- Evaluation
of possible sampling errors (e.g., migration); and
- Assessment
of social and economic determinants of vulnerability to
HIV infection.
- With governments
assuming increasing responsibilities for supporting surveillance
systems and the evolving role of both multilateral and bilateral
donors, it will be critical to determine the costs and secure
the necessary resources to implement HIV surveillance data gathering
systems.
The following
table proposes both a minimum and an advanced resourceintensive
surveillance system for various stages of the epidemic. It should
be acknowledged that multiple others aspects should be considered
when designing surveillance systems, including:
- The size
of a country;
- The type
of decisions that need to be made on the basis of surveillance
data; and
- The availability
of structures and resources.
Minimal
and Advances Surveillance Systems at Different Stages of HIV/AIDS
Epidemics
|
Stages
of the Epidemic
|
Minimal
Information Needs
|
Advanced/
Resource-Intensive Surveillance Systems
|
| Early/Slow:
Few cases of AIDS, low HIV prevalence in "high-risk" groups
and spread mainly in urban areas. |
1.Serial
(6 monthly) HIV prevalence focusing on selected "high-risk
groups".
2.AIDS
case reporting.
3.Selected
STI prevalence studies.
4.Development
of baseline levels of risk behaviors.
|
Minimal
package plus: Qualitative and quantitative data on social/sexual
mixing, selected STI prevalence, identification of potential
determinants of vulnerability to HIV infection. |
| Middle:
Increasing HIV prevalence in "high-risk" groups, low prevalence
in general adult population, continued spread mainly in urban
areas. |
1. Serial
(6 monthly) HIV prevalence of populations with high-risk
behaviors.
2.AIDS
case reporting.
3.Selected
STI prevalence studies.
4.HIV
prevalence in low-risk groups (e.g.. women attending antenatal
clinics, blood donors).
|
Above
plus: Health-seeking behavior surveys, monitoring of impact
of interventions, e.g., condom utilization, as well as any
interventions directed toward vulnerability issues, consider
population based seroprevalence studies. |
| Late:
High prevalence in populations with high-risk behaviors: increasing
prevalence in general adult population. |
1. Serial
(annual) HIV prevalence of high-risk groups and population
with low-risk behaviors.
2.AIDS
case reporting.
3.Selected
surveys of behavior change and STI prevalence coupled to
#1.
|
Above
plus: AIDS-related case mortality, health care utilization,
increasing ability to monitor trends in gender roles, sexual
negotiation, HIV subtype determination. |
| Mature/Endemic
in General Population: High (>5%) HIV prevalence in general
adult populations; gradual urban to rural equalization of
HIV prevalence. |
1. Serial
(annual) HIV prevalence in populations with high-risk behaviors
and others with low-risk behaviors.
2.AIDS
case reporting.
3.Selected
behavioral surveys and STI prevalence linked with epidemiologic
information.
|
All
of the above plus: Selected impact studies on health care
and other sectors of society, evaluation of quality of facility-based
care and orphan support, evaluation of discrimination. |
5. Inadequate
behavioral and social data make it difficult to interpret the
apparently slower growth of epidemics in some countries, as is
observed in the Philippines and Zaire. Also difficult to explain
have been the recent explosive epidemics in South Africa and Botswana,
as well as the rapid rise in Cambodia.
6. As the
impact of the pandemic is increasingly felt, care and support
for people living with HIV/AIDS continues to be grossly inadequate,
especially in developing countries and among disenfranchised populations
in industrialized countries.
Recommendations
1.Improvements
are needed in the collection and analysis of surveillance data,
including epidemiological, behavioral and socioeconomic data in
order to:
- Monitor
the status and trends of the epidemics adequately: HIV prevalence
data should be emphasized rather than AIDS cases; reporting
should be focused on current rather than cumulative cases; surveillance
systems and epidemiological studies should be capable of disaggregating
data according to sex and narrow age groups in order to reveal
trends occurring within the excessively broad population groups
currently used to monitor HIV/AIDS and behaviors;
- Interpret
the changes in HIV/AIDS trends;
- Detect
potentially explosive epidemics in their early stages; and
- Understand
the reasons for relatively slow epidemics as well as rapid epidemics.
2. Prevention
efforts should be focused on women, young adults, adolescents
and marginalized communities
3. Special
attention must be given to the explosive epidemics in India, Cambodia,
Myanmar and South Africa and to those countries and areas with
the potential for explosive epidemics, such as Indonesia, Eastern
Europe and several countries in West Africa.
4. Current
successes in prevention and interventions that are known to work
must be enhanced both in quality and scale to all populations
at risk of HIV/AIDS.
5. Research
must be done on the societal, social, behavioral and economic
determinants of vulnerability to HIV/AIDS. Both strong qualitative
and quantitative research methods will be needed to effectively
investigate these determinants.
6. Dissemination
of results at all levels is an essential component of research
and surveillance.
7. Close
linkages at the local, national and global levels should be strengthened
and maintained among epidemiologists, behavioral scientists, public
health specialists, HIV/AIDS workers and non-governmental and
private voluntary organizations in order to improve prevention
and care efforts and to monitor trends and evaluate program impacts.
8. The observed
epidemic trends require continuous improvement of policy commitment
and increased mobilization of financial resources for prevention
and care efforts at the local, national and international levels.
This Final
Report is the product of collective work involving all participants
in the Satellite Symposium and support staff. The inital texts
of short summaries that now appear as boxes throughout this report
have been contributed by the following Symposium participants:
Box
1: Mwanza STD Trial / Richard Hayes
Box
2: Declines in HIV in Uganda / Rand Stoneburner
Box
3: HIV/AIDS in India / Shiv Lal, Manoj Jain
Box
4: Eastern Europe and the Ukraine / Alexander Gromyko
Box
5: HIV Subtypes / Bruce Weniger
Box
6: Surveillance Collection / Bilali Camara, James Chin,
Paul Delay, John Kaldor, Karen Stanecki DeLay, Rand Stoneburner
and Peter Way
List of
Participants
Symposium
Co-Chairs
Peter Lamptey
- AIDSCAP/Family Health International, USA
Daniel Tarantola
- François-Xavier Bagnoud Center for Health and Human Rights
of the Harvard School of Public Health, USA
Symposium
Participants
E. Maxine
Ankrah - AIDSCAP/Family Health International, USA
Chris Archibald
- Bureau of HIV/AIDS and STD, Canada
Kwame Asiedu
- AIDSCAP/Family Health International, Kenya
Seth Berkley
- Rockefeller Foundation, USA
Stephen Blount
- Caribbean Epidemiology Center, Trinidad
Tim Brown
- East-West Center, USA
Jean Baptiste
Brunet - European Centre for the Epidemiological Monitoring
of AIDS, France
Anne Buvé
- Institute of Tropical Medicine, Belgium
Ricardo Calderón
- AIDSCAP/Family Health International, USA
Bilali Camara
- Caribbean Epidemiology Center, Trinidad
Pedro Chequer
- Ministry of Health, Brazil
James Chin
- University of California, Berkeley,
Escaroles
Del Rio - National Council for AIDS Prevention and Control
(CONASIDA), Mexico
Paul DeLay
- U.S. Agency for International Development, USA
Alex Gromyko
- World Health Organization, Denmark
Sofia Gruskin
- François-Xavier Bagnoud Center for Health and Human Rights
of the Harvard School of Public Health, USA
Osamah Hamouda
- Robert Koch Institute, Germany
Catherine
Hankins - Group for Action-Research, McGill AIDS Centre, Canada
Richard Hayes
- Johns Hopkins School of Public Health, USA
Jaafar Heikel
- Ministry of Public Health, Morocco (in absentia)
Manoj Jain
- Tufts University School of Medicine and the University of
Tennessee, USA
John Kaldor
- National Centre in HIV Epidemiology and Clinical Research,
University of New South Wales, Australia
Mitsuhiro
Kamakura - Department of Preventive Medicine and Public Health,
Keio University School of Medicine, Japan
Irena Klavs
- Institute of Public Health, Slovenia
Shiv Lal -
National AIDS Control Organization, India
Sophie Lallemant-Le
Coeur - Institut National d'Etudes Démographiques, France
Rob Moodie
- The Joint United Nations Programme on HIV/AIDS (UNAIDS),
Switzerland
Deborah Murray
- AIDSCAP/Family Health International, USA
Warren Naamara
- AIDSCAP/Family Health International, Zimbabwe
Ibra Ndoye
- Programme National de Lutte Contre le SIDA (PNLS), Senegal
Mary O'Grady
- AIDSCAP/Family Health International, USA
Wiput Phoolcharoen
- Ministry of Public Health, Thailand
Peter Piot
- The Joint United Nations Programme on HIV/AIDS (UNAIDS), Switzerland
Elizabeth
Preble - AIDSCAP/Family Health International, USA
Claude Raynaut
- Sociétés d'Afrique et SIDA, University of Bordeaux II, France
Thomas Rehle
- AIDSCAP/Family Health International, USA
Deborah Rugg
- Centers for Disease Control and Prevention, USA
Werasit Sittitrai
- The Joint United Nations Programme on HIV/AIDS (UNAIDS),
Switzerland
Karen Stanecki
DeLay - U.S. Bureau of Census, USA
Elaine Stevenson
Macfarlane - Burnet Centre for Medical Research, Australia
Rand Stoneburner
- World Health Organization, Switzerland
Steffanie
Strathdee - BC Centre for Excellence in HIV/AIDS, Canada
Donald Sutherland
- Bureau of HIV/AIDS & STD, Canada
Johannes Van
Dam - The Joint United Nations Programme on HIV/AIDS (UNAIDS),
Switzerland
John Ward
- Centers for Disease Control and Prevention, USA
Peter Way
- U.S. Bureau of Census, USA
Bruce G. Weniger
- Centers for Disease Control and Prevention, USA
Eka Esu-Williams
- AIDSCAP/Family Health International, Nigeria
Zheng Xiwen
- Chinese Academy of Preventive Medicine, China
Fernando Zacarias
- Pan American Health Organization, USA
Debrework
Zewdie - The World Bank, USA
The United
Nations Population Fund (UNFPA) and The United States Agency for
International Development provided partial funding for The Status
and Trends of the Global HIV/AIDS Pandemic satellite symposium.
|