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The Epidemiology of HIV Among MSM in Low- and Middle-Income
Countries: High Rates, Limited Responses
Stefan
Baral, Frangiscos Sifakis, Farley Cleghorn, Chris
Beyrer
In
many regions of the world, HIV first emerged among populations of men who have
sex with men (MSM) (1).
More
than a quarter-century later and in an increasingly broad range of countries,
contexts, and development levels, male-to-male sexual contact remains an
important route
of HIV transmission. Men who have sex with men is
a technical phrase intended to be less stigmatizing than
culturally bound terms such as gay, bisexual, or homosexual. It
describes same-sex behaviours between men rather than identities, orientations,
or cultural categories. Therefore, the
term MSM includes gay men, bisexuals, MSM who do not identify as gay or
bisexual despite
their behaviours, male sex workers, transgendered
people, and a range of culture- and country-specific populations of
MSM. MSM belonging to these diverse
populations may have both individual
and network-level risks and these groups may have diverging HIV epidemic
dynamics. It may be a long time before the differential risk status of these
various populations can be accurately described, given
the homophobia that is prevalent in many countries and the limited funding
available for studies and programs targeting
MSM. Nevertheless, recent data indicate that HIV prevalence among MSM is high
and rising across these groups, and that these epidemics are no longer limited
to the high-income countries in which they were initially
described. These studies have demonstrated high HIV prevalence among MSM from a
number of low- and middle-income
country settings (2). In certain countries—such as Thailand, Cambodia, and
Senegal—with relatively low and declining HIV prevalence among heterosexual populations
but high prevalence among MSM, the data suggest concentrated HIV epidemics
among MSM and a “dislinked” epidemic pattern (3-7). These men exhibit ongoing high
HIV prevalence against a backdrop of declining general population epidemics.
Despite these significant findings,
this continues to be an understudied and underserved population.
There
are strong data supporting the preventive efficacy of circumcision among
heterosexual men, but among MSM there exist only limited observational data
regarding the possible protective effect of adult circumcision on HIV
acquisition (9-18). Being a black or minority ethnic man
who has sex with men in high-income country settings is associated with a
higher risk of HIV compared to white MSM (19). A critical review of the
evidence examining the
racial differential seen in the HIV epidemic among MSM suggested that the
increased HIV prevalence seen among black MSM is most likely due to the fact
that a lower
proportion of them have been tested and know their HIV status, as well as to
higher rates of sexually transmitted infections (STIs), which facilitate HIV
transmission (20). These individual risk factors likely transcend geography,
whereas the higher-level structural risk factors vary significantly between
countries and continents. In particular, high-risk behaviours such as those
common among male sex workers, transgendered people, and
MSM
who inject drugs, likely put all the members of a sexual network at increased
risk of infection (7). A high prevalence of STIs increases the probability of
HIV transmission within a network. At the community level, access to prevention
services, voluntary counselling and testing, and antiretroviral treatment (ART) can help
diminish risk within MSM communities. Finally, the more advanced an HIV
epidemic is, the greater the risk to lower-order determinants of HIV infection.
In
countries such as the U.S., HIV prevention and treatment efforts have been
mainstreamed to target the general population. However, as of 2005, 72% of all
HIV infections among men in the U.S. were related to MSM (21). MSM are the only
vulnerable group with no significant decrease
in transmission rates in the U.S. from 2001 to 2004 (22). Active surveillance
in Baltimore has demonstrated HIV
prevalence as high as 46% among African-American MSM, 67% of whom were unaware
of their status. HIV prevalence was 21% among white MSM, 18% of whom were
unaware of their status. These data suggest that
HIV continues to have a disproportionate impact on MSM in the U.S., and that
these epidemics continue to grow.
To
see if this disproportionate HIV burden also affected MSM in lower-income
settings, in 2006 we examined a random sample of low- and middle-income
countries and found
some notable trends. First, it was difficult even to find studies of the
prevalence of male-male sexual contact in lower-income settings, and second,
where HIV data were
available, prevalence was consistently high. To be able to draw more concrete
conclusions, we completed a systematic review and meta-analysis of this topic
in 2007. This review confirmed that HIV has spread widely in Asia, Africa, and
Latin America, and that MSM are at increased risk
of HIV infection compared to the general population of reproductive age adults,
even in settings with high HIV prevalence.
The
review evaluated 63,538 men from 38 countries and demonstrated an overall HIV
prevalence among MSM of 12.8%. Studies from the 16 Latin American countries included
38,013 MSM with an overall HIV prevalence of 16.1%, compared to a general
regional population HIV prevalence of 0.5%. Studies from 10 Asian countries included
19,142 men with an HIV prevalence of 11.4%, compared to a general regional
prevalence of 0.1–0.3%. Though there were no published studies from the former Soviet
Union and Eastern Europe, data were available from 12 countries in this region
and demonstrated an HIV prevalence among 8,609 MSM of 1.2%, compared to a
general regional prevalence of 0.9%. Limited data
were
also available from Africa, where studies from four countries included 2,353
MSM with an HIV prevalence of 13.0%, compared to a general regional prevalence
of 5.0%.
Looking
at the more widely available data from Latin America, there have been
significant differences within the region in the responses to HIV epidemics
among MSM, which have likely resulted in different epidemic dynamics, even
between neighbouring countries. For example, in Peru, MSM are included in
national HIV surveillance programmes, and targeted HIV prevention expenditures match
the relative burden of disease among MSM. HIV prevalence among MSM sampled was
12.2% with an odds ratio (the probability of being HIV positive relative to the
general population) of 22.6 times greater than the general
population (23). This can be contrasted to Bolivia, where programming and
spending on MSM as a proportion
of
total HIV prevention expenditures are less than one half of the proportion that
MSM contribute to the country’s
HIV epidemic. In Bolivia, HIV prevalence among MSM was 21.5%, with an odds
ratio of 178.8 above the baseline general population prevalence. These
differences between countries are likely related to structural risk
factors for HIV infection among MSM, rather than individual level risk factors.
With some exceptions, Latin American countries have included indicators on MSM in
their national AIDS strategies, but the high HIV prevalence speaks to the
continued need for expansion within these programmes to be in line with the
relative HIV burden among MSM. Similar to Latin America, HIV in Asia tends to
be highly concentrated among subpopulations, including MSM.
Many
of these epidemics seem to be occurring separately from what is happening in
the general population.
Consequently,
the regional average probability of being infected with HIV is 33.3 for MSM in
Latin America, and 18.7 for MSM in Asia. In both cases, the HIV infection risk for
MSM is much greater than for the general population. Given that Asia makes up
the majority of the global population, it is surprising that, as of 2007, data
were only
available from 19,142 men from seven countries in the region. The vast and
diverse Asian continent contains very different HIV epidemics, as can be seen
by comparing countries
such as Thailand and China. In Thailand, HIV prevalence among 3,236 MSM sampled
was 24.6%, compared to a prevalence rate of 3.8% among 6,270 MSM in
China. However, while the absolute risk among MSM of being infected with HIV
was higher in Thailand, MSM in China were at higher risk of HIV infection
compared to the general
population. Specifically, while MSM in Thailand were approximately 20 times
more likely than the general population to have HIV, MSM in China were more than
45 times more likely than the general population to be HIV positive. Thus,
while programming has tended to focus on the absolute risk of HIV infection, it
is also key to consider the relative risk of HIV infection among MSM in these
settings. In Asia, prevention expenditures targeting MSM range from barely more
than zero in parts of China to
a high of 4% of all prevention expenditures in Thailand, highlighting the
ongoing disparity between the burden of disease
among MSM and the level of spending on prevention programmes for this
population (23). The high prevalence of HIV infection and high odds ratios among
MSM are quite consistent across most individual countries and geographic regions,
as well as all States
(low-level, concentrated, and generalized). Eastern Europe appears to be an
exception: data on MSM are scarce, and the region’s HIV epidemics are primarily driven
by injection drug use. Since an unknown but potentially significant number of
MSM in this region may also be injection drug users, it may be difficult to
estimate the
attributable risk fraction—the portion of the total burden of
the epidemic that can be attributed to a particular cause—for
these differing behaviours. What is clear is the need for better
characterization of the risks for MSM in this region and for the development of
effective prevention programmes
to curb these epidemics.
Data
regarding MSM in Africa are the sparsest in the world, but are beginning to
emerge. One of the earliest studies
was published in 2005 in Senegal, where 463 MSM from Dakar and four other urban
communities demonstrated an HIV prevalence of 21.5%. STI prevalence among
MSM was 4.8% for active syphilis, 22.3% for herpes simplex virus II, 4.1% for
chlamydia, and 5.4% for gonorrhoea. A 2005 study of 713 receptive MSM from Khartoum,
Sudan, revealed a mostly Muslim population with an HIV prevalence of 9.3%. The
best-developed data have been generated in Kenya, with the support of the
Kenyan National AIDS Council. Groups throughout the country have shown HIV
prevalence as high as 43% among
MSM (24-26). In Nigeria, a recent study hosted by the Ministry of Health
characterized the risk of MSM
across
the country and found that their overall HIV prevalence was 13.5%, though
prevalence varied significantly
between
sites of study (27). Specifically, HIV prevalence among MSM in Cross River was
2.8%, 11.7% in Kano, and 25.4% in Lagos. The combination of these studies suggests
that even in the generalized HIV epidemics of
sub-Saharan Africa, MSM are nearly four times more likely to be infected
with HIV than the general population.
Data
on HIV prevalence among MSM are currently being generated or analyzed in
Botswana, Ghana, Ivory Coast, Malawi, Namibia, South Africa, and Zambia, among
other countries. While these data are preliminary, they clearly demonstrate
that MSM not only exist in Africa, they are also at risk for HIV infection and
in need of targeted prevention programming.
Decreasing
the relative burden of disease among MSM will
require a concerted effort and a strategic approach. We suggest that any such strategy
should include at least three main components: increased
surveillance, enhanced research, and targeted prevention programmes. Surveillance
is the ongoing collection, collation, and analysis of data and the
timely dissemination of information to those who need it. Surveillance of MSM
in low and middle-income countries to date has been largely carried out through
research, and only a few countries have included MSM in national surveillance
programmes. However, where available, prevalence data have demonstrated a
consistent and disproportionately high burden of HIV among MSM. National
surveillance systems should consider this high
burden of disease and include MSM in countries where they are currently
excluded. Methodologically sound surveillance can help determine and
demonstrate the need for targeted HIV prevention expenditures from regional,
national, and international funding agencies.
Prevention
expenditures should be allocated according to evidence-based need. To this end,
it is important to use research to generate data proving that HIV epidemics in low-
and middle-income countries are real. Enhanced research can also inform the
design of prevention strategies, and eventually serve to evaluate these
prevention programmes after their initiation. Given
documented high HIV prevalence among MSM, it is also vital to enact targeted
and evidence-based prevention programs for these men. The goal of these programmes
is to decrease HIV transmission among men by increasing condom use during anal
sex and employing other evidence-based biomedical interventions. We already
know that these prevention strategies can work.
Research
among MSM in low- and middle-income countries has been limited by the
criminalization and social stigmatization of their behaviour, safety
considerations for
study participants, the hidden nature of this population, and lack of targeted
funding. Thus, most available data evaluating determinants of HIV risk among
MSM are derived
from high-income countries. Available evidence from these countries suggests
that structural risks— social,
economic, political, or legal factors—are important in defining HIV risk for
any one man. Individual-level acquisition
risks have focused on the highest probability exposure: unprotected anal
intercourse, and specifically on receptive anal intercourse (8). Use of “party”
or “club” drugs
has been associated with heightened sexual exposure risk among MSM, and, as with
men who only report sex with women, HIV transmission in MSM is associated with
genito-urinary disease. However, high frequency of male partners and a high
lifetime number of male partners
are also relevant (7-9).
A
recent systematic review and meta-analysis including 16,224 men in 38
experimental and observational studies
demonstrated
that compared to controls with no interventions, study groups reduced
unprotected anal intercourse by 27% (28;29). In an additional 16 studies where
MSM were given targeted prevention strategies, study groups decreased
unprotected anal intercourse by 17%, compared to MSM who received standard HIV
prevention measures.
Prevention
strategies tend to work better when community-level rather than individual
risks are targeted. These strategies functioned equally well independent of the proportion
of minorities included. Globally, only 5–10% of MSM have access to programmes
such as these, with the majority
taking place in high-income countries (30;31). However, studies of
interventions targeting MSM in low- and middle-income settings have
consistently demonstrated
both the need for and effectiveness of these programs (32-35). Although
prevention strategies targeting MSM have been shown to be effective across country
income levels, the benefit of these interventions has been subject to decay
over time, indicating that programmes should be ongoing to preserve increased
condom usage.
Effective
arguments for improved HIV programming for MSM can be made both from public
health and human rights perspectives. The data presented here make a clear case
that MSM exist and are at risk for HIV infection throughout the world.
Moreover, ignoring and stigmatizing high-risk
population groups has never proven to be an effective tool in curbing HIV
epidemics. From a human rights perspective, discrimination on the basis of sex,
which includes sexual orientation, is prohibited by the
International Covenant on Civil and Political Rights signed in 1966, of which
most states, including all African countries,
are signatories. In 1994, the United Nations held that sexual orientation was a
status protected under this covenant from discrimination, with “sex” including “sexual
orientation.” Whether one gives more weight to the public health or the human
rights argument, the conclusion is the same: It is time to comprehensively address
the AIDS pandemic, and to do so effectively, all
vulnerable populations—including MSM—should be included in HIV prevention
programs.
References
(1) Caceres C, Konda K, Pecheny M, et al. “Estimating the number
of men who have sex with men in low and middle income countries.” Sex Transm Infect. 2006
June;82 Suppl 3:iii3-iii9. (2) Baral S, Sifakis F, Cleghorn F, et
al. “Elevated risk for HIV infection among men who have sex with men in low-
and middle-income countries
2000-2006: A systematic review.” PLoS Med. 2007 December 1;4(12):e339.
(3) Beyrer C. “HIV epidemiology update and transmission factors: Risks and risk
contexts.”
2006. (4) “HIV prevalence among populations of men who have sex
with men—Thailand,” 2003 and 2005. MMWR. 2006 August 11;55(31):844–8. (5) Wade AS, Kane CT,
Diallo PA, et al. “HIV infection and sexually transmitted
infections among men who have sex with men in Senegal.” AIDS. 2005 December
2;19(18):2133–40. (6) Girault
P, Saidel T, Song N, et al. “HIV, STIs, and sexual behaviors among
men who have sex with men in Phnom Penh, Cambodia.” AIDS Educ Prev. 2004
February;16(1):31–44.
(7) Beyrer C, Sripaipan T, Tovanabutra S, et al. “High HIV,
hepatitis C and sexual risks among drug-using men who have sex with men in
northern Thailand.” AIDS.
2005 September 23;19(14):1535–40. (8) Koblin BA, Husnik MJ, Colfax
G, et al. “Risk factors for HIV infection among men who have sex with men.” AIDS. 2006 March
21;20(5):731–9. (9) Buchbinder SP, Vittinghoff E, Heagerty PJ, et
al. “Sexual risk, nitrite inhalant use, and lack of circumcision associated
with HIV seroconversion in men
who have sex with men in the United States.” J Acquir Immune Defic Syndr. 2005
May 1;39(1):82–9. (10) Auvert B, Taljaard D, Lagarde E, et al. “Randomized,
controlled
intervention trial of male circumcision for reduction of HIV
infection risk: The ANRS 1265 Trial.” PLoS
Med. 2005 November;2(11):e298. (11) Bailey RC, Moses S,
Parker
CB, et al. “Male circumcision for HIV prevention in young men in
Kisumu, Kenya: A randomised controlled trial.” Lancet. 2007 February
24;369(9562):643–56. (12) Gray
RH, Kigozi G, Serwadda D, et al. “Male circumcision for HIV
prevention in men in Rakai, Uganda: A randomised trial.” Lancet. 2007 February
24;369(9562):657–66.
(13) Kreiss JK, Hopkins SG. “The association between circumcision
status and human immunodeficiency virus infection among homosexual men.” J Infect Dis. 1993
December;168(6):1404–8. (14) Krieger JN, Bailey RC, Opeya J, et
al. “Adult male circumcision: Results of a standardized procedure in Kisumu
District, Kenya.” BJU Int.
2005 November;96(7):1109–13. 15) Millett GA, Ding H, Lauby J, et
al. “Circumcision status and HIV infection among black and Latino men who have
sex with men in
three U.S. cities.” J
Acquir Immune Defic Syndr. 2007 December
15;46(5):643–50. (16) Siegfried N, Muller M, Volmink J, et al. “Male
circumcision for prevention of heterosexual
acquisition of HIV in men.” Cochrane
Database Syst Rev. 2003;(3):CD003362. (17)
Templeton DJ, Jin F, Prestage GP, et al. “Circumcision status and risk of HIV
seroconversion in the HIM cohort of homosexual men in Sydney.”
(Abstract WEAC103). 2007 Jul 25; Sydney: IAS; 2007. (18) UNAIDS. “New data on
male circumcision
and HIV prevention: policy and programme implications.” Geneva:
UNAIDS; 2007. (19) Harawa NT, Greenland S, Bingham TA, et al. “Associations of
race/ethnicity with
HIV prevalence and HIV-related behaviors among young men who have
sex with men in seven urban centers in the United States.” J Acquir Immune Defic Syndr. 2004
April 15;35(5):526–36. (20) Millett GA, Peterson JL, Wolitski RJ,
et al. “Greater risk for HIV infection of black men who have sex with men: A
critical literature review.”
Am J Public Health. 2006
June;96(6):1007–19. (21) CDC. HIV/AIDS
Surveillance Report: Cases of HIV infection and AIDS in the United States and
Dependent Areas, 2005.
Atlanta: CDC; 2007 Jun; Volume 17. (22) Hall HI, Byers RH, Ling Q,
et al. “Racial/ethnic and age disparities in HIV prevalence and disease
progression among men who
have sex with men in the United States.” Am J Public Health. 2007
June;97(6):1060–6. (23) USAID and Health Policy Initiative. “HIV expenditure on
MSM programming
in the Asia-Pacific region.” Washington D.C.: Constella Futures;
2006 Sep. (24) Geibel S, Onyango-Ouma W, Birungi H. “Factors associate with
reported STI symptoms
among MSM in Nairobi, Kenya.” Abstract CDD0340. Toronto 2006. (25)
Geibel S, van der Elst EM, King’ola N, et al. “’Are you on the market?’: A
capture-recapture enumeration
of men who sell sex to men in and around Mombasa, Kenya.” AIDS. 2007 June;21(10):1349–54. (26)
Sanders EJ, Graham SM, Okuku HS, et al. “HIV-1 infection
in high risk men who have sex with men in Mombasa, Kenya.” AIDS. 2007 November
30;21(18):2513–20. (27) Nigerian Federal Ministry of Health and FHI. Integrated
Biological and Behavioural Surveillance Survey. Nigeria; 2008 May
2. (28) Herbst JH, Sherba RT, Crepaz N, et al. “A meta-analytic review of HIV
behavioral interventions
for reducing sexual risk behavior of men who have sex with men.” J Acquir Immune Defic Syndr. 2005
June 1;39(2):228–41. (29) Johnson WD, Holtgrave DR, McClellan
WM, et al. “HIV intervention research for men who have sex with
men: A seven-year update.” AIDS Educ Prev. 2005 December;17(6):568–89. (30)
UNAIDS. 2005 Update
on the Global HIV/AIDS Pandemic.
Geneva: UNAIDS; 2005. (31) UNAIDS. 2006 Report
on the Global AIDS Epidemic. Geneva: UNAIDS;
2006. (32) Amirkhanian YA, Kelly
JA, Kabakchieva E, et al. “Evaluation of a social network HIV
prevention intervention program for young men who have sex with men in Russia
and Bulgaria” AIDS
Educ Prev. 2003 June;15(3):205–20. (33)
Amirkhanian YA, Kelly JA, Kabakchieva E, et al. “A randomized social network
HIV prevention trial with young men who have
sex with men in Russia and Bulgaria.” AIDS. 2005 November
4;19(16):1897–905. (34) Choi KH, McFarland W, Kihara M. “HIV prevention for
Asian and Pacific Islander
men who have sex with men: Identifying needs for the Asia Pacific
region.” AIDS Educ Prev. 2004 February;16(1):v–vii. (35) Operario D, Nemoto T, Ng T, et
al. “Conducting
HIV interventions for Asian Pacific Islander men who have sex with
men: Challenges and compromises in community collaborative research.” AIDS Educ Prev. 2005
August;17(4):334–46.
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