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New Paradigms of Risk and Protection

New Paradigms of Risk and Protection
Reported by
Nicholette Zeliadt

Posted January 28, 2013

Presented By


Despite tremendous progress in confronting the global HIV epidemic, new HIV infections continue to increase among gay, bisexual, and other men who have sex with men (MSM) in rich and poor countries alike. The New Paradigms of Risk and Protection: Understanding the HIV Epidemics among Gay and Bisexual Men conference, presented on December 7, 2012, by the Johns Hopkins Bloomberg School of Public Health and the New York Academy of Sciences, discussed the key drivers of the HIV epidemic in this population, including the biology of anal sex, the characteristics of MSM networks, and behavioral factors. The event also explored the unique challenges faced by black MSM around the world and discussed tools and initiatives that could help to turn the tide for this unresolved component of the HIV / AIDS epidemic.

Use the tabs above to find a meeting report and multimedia from this event.

Presentations available from:
Stefan Baral, MD, MPH, MBA (Johns Hopkins Bloomberg School of Public Health)
Chris Beyrer, MD, MPH (Johns Hopkins Bloomberg School of Public Health)
Chris Collins, MPP (amfAR, The Foundation for AIDS Research)
Thomas Farley, MD, MPH (New York City Department of Health and Mental Hygiene)
Kenneth Mayer, MD (Harvard Medical School; Fenway Health)
Gregorio Millett, MPH (Centers for Disease Control and Prevention)
Patrick Sullivan, PhD, DVM (Emory University)
Chris Beyrer presented on behalf of Patrick Sullivan.

Presented by

  • The New York Academy of Sciences
  • The Johns Hopkins Bloomberg School of Public Health


Chris Beyrer (Johns Hopkins Bloomberg School of Public Health)

Global Epidemiology of HIV Infection among Men Who Have Sex with Men

Stefan Baral (Johns Hopkins Bloomberg School of Public Health)

Successes and Challenges of HIV Prevention in Men Who Have Sex with Men

Patrick Sullivan (Emory University); Presented by Chris Beyrer

Caring for the Whole Person: Comprehensive Health Services for MSM

Kenneth Mayer (Harvard Medical School; Fenway Health)

Meta-analysis of HIV Infection Disparities among Black MSM in the U.S., Canada, and UK

Gregorio Millett (Centers for Disease Control and Prevention)

Common Roots: HIV Infection Disparities among Black MSM Across the Africa Diaspora

Gregorio Millett (Centers for Disease Control and Prevention)

Call to Action for Comprehensive HIV Services for Men Who Have Sex with Men

Chris Collins (amfAR, The Foundation for AIDS Research)

Guest Presentation

Thomas Farley (New York City Department of Health and Mental Hygiene)

Panel Discussion

Moderator: Chris Beyrer (Johns Hopkins Bloomberg School of Public Health)
  • 00:01
    1. Diversifying the message; Self-reporting; The role of social media
  • 26:22
    2. Country of origin and risk behavior; Communication without stigma
  • 33:35
    3. Age, religion, and transgender datasets; The dual message
  • 53:32
    4. Structural and clinical factors; Conclusio


amfAR, The Foundation for AIDS Research

The Black AIDS Institute

The Centers for Disease Control and Prevention

The Fenway Institute, The National LGBT Health Education Center

Office of National AIDS Policy, National HIV/AIDS Strategy

Books & Reports

Beyrer C, Wirtz AL, Walker D, et al. The Global HIV Epidemics among Men Who Have Sex with Men. Washington, DC: The World Bank; 2011.

Committee on Lesbian, Gay, Bisexual, and Transgender Health Issues and Research Gaps and Opportunities, Institute of Medicine. The Health of Lesbian, Gay, Bisexual, and Transgender People: Building a Foundation for Better Understanding. Washington, DC: The National Academies Press; 2011.

Makadon HJ, Mayer KH, Potter J, Goldhammer H, eds. The Fenway Guide to Lesbian, Gay, Bisexual, and Transgender Health. 1st ed. Philadelphia: American College of Physicians; 2007.

President's Emergency Plan for AIDS Relief. PEPFAR Blueprint: Creating an AIDS-free generation. 2012.

World Health Organization. Prevention and treatment of HIV and other sexually transmitted infections among men who have sex with men and transgender people: recommendations for a public health approach. Geneva, Switzerland; 2011.

Journal Articles

Baggaley R, White RG, Boily M. HIV transmission risk through anal intercourse: systematic review, meta-analysis and implications for HIV prevention. Int J Epidemiol. 2010;39(4):1048-63.

Beyrer C, Baral SD, van Griensven F, et al. Global epidemiology of HIV infection in men who have sex with men. Lancet. 2012;380(9839):367-77.

Beyrer C, Sullivan PS, Sanchez J, et al. A call to action for comprehensive HIV services for men who have sex with men. Lancet. 2012;380(9839):424-38.

Coates TJ, Richter L, Caceres C. Behavioural strategies to reduce HIV transmission: how to make them work better. Lancet. 2008;372(9639):669-84.

Glick S, Golden M. Persistence of racial differences in attitudes toward homosexuality in the United States. J Acquir Immune Defic Syndr. 2010;55(4):516-23.

Grulich A, Zablotska I. Commentary: probability of HIV transmission through anal intercourse. Int J Epidemiol. 2010 39(4):1064-5.

Lewis F, Hughes GJ, Rambaut A, et al. Episodic sexual transmission of HIV revealed by molecular phylodynamics. PLoS Med. 2008;5(3):e50.

Li H, Bar KJ, Wang S, et al. High multiplicity infection by HIV-1 in men who have sex with men. PLoS Pathog. 2010;6(5):e1000890.

Mansergh G, Koblin BA, Sullivan PS. Challenges for HIV pre-exposure prophylaxis among men who have sex with men in the United States. PLoS Med. 2012;9(8):e1001286.

Mayer KH, Bekker L-G, Stall R, et al. Comprehensive clinical care for men who have sex with men: an integrated approach. Lancet. 2012;380(9839):378-87.

Mayer KH, Bradford JB, Makadon JH, et al. Sexual and gender minority health: what we know and what needs to be done. Am J Public Health. 2008;98(6):989-95.

Millett GA, Flores SA, Peterson JL, Bakeman R. Explaining disparities in HIV infection among black and white men who have sex with men: a meta-analysis of HIV risk behaviors. AIDS. 2007;21(15):2083-91.

Millett GA, Jeffries WL 4th, Peterson JL, et al. Common roots: a contextual review of HIV epidemics in black men who have sex with men across the African diaspora. Lancet. 2012;380(9839):411-23.

Millett GA, Peterson JL, Flores SA, et al. Comparisons of disparities and risks of HIV infection in black and other men who have sex with men in Canada, UK and USA: a meta-analysis. Lancet. 2012;380(9839):341-8.

Prejean J, Song R, Hernandez A, et al. Estimated HIV incidence in the United States, 2006–2009. PLoS One. 2011;6(8):e17502.

Sullivan PS, Carballo-Diéguez A, Coates T, et al. Successes and challenges of HIV prevention in men who have sex with men. Lancet. 2012;380(9839):388-99.

Trapence G, Collins C, Avrett S, et al. From personal survival to public health: community leadership by men who have sex with men in the response to HIV. Lancet. 2012;380(9839):400-10.

Special Guest Speaker

Thomas Farley, MD, MPH

New York City Department of Health and Mental Hygiene
e-mail | website | publications

Thomas Farley was appointed New York City Health Commissioner in May 2009. Before joining the agency, Farley was chair of the Department of Community Health Sciences at the Tulane University School of Public Health and Tropical Medicine. He received MD and MPH degrees from Tulane University. Trained as a pediatrician, he previously served in the Centers for Disease Control and Prevention's Epidemic Intelligence Service and worked for the CDC and the Louisiana Office of Public Health., where he directed programs to control various infectious diseases. His research has covered a wide range of topics, including Legionnaires' disease, prevention of HIV/STDs, infant mortality, and obesity. Farley is coauthor with RAND Senior Scientist Deborah Cohen of Prescription for a Healthy Nation.


Stefan Baral, MD, MPH, MBA

Johns Hopkins Bloomberg School of Public Health
e-mail | website | publications

Stefan Baral is a physician epidemiologist and a professor in the Department of Epidemiology at the Johns Hopkins School of Public Health and is the associate director for key populations for the Center for Public Health and Human Rights. Baral completed his medical school training at Queen's University and his residency at the University of Toronto, both in Ontario, Canada. Baral has two core research interests: assessing the epidemiology of HIV and sexually transmitted infections among the most at risk populations, including gay men and other men who have sex with men and sex workers; and characterizing effective HIV-prevention strategies. Baral has led epidemiological studies among men who have sex with men and sex workers in southern, eastern, and western African countries, as well as in Central and Southeast Asia. In addition, Baral has worked on global HIV-prevention studies to characterize effective combination HIV-prevention packages, funded by the World Bank, for men who have sex with men, female sex workers, and people who use drugs. Baral's work has also been funded by USAID and the NIH.

Chris Beyrer, MD, MPH

Johns Hopkins Bloomberg School of Public Health
e-mail | website | publications

Chris Beyrer is a professor in the Departments of Epidemiology, International Health, and Health, Behavior and Society at the Johns Hopkins Bloomberg School of Public Health. Beyrer holds an MD from SUNY Downstate and an MPH from Johns Hopkins School of Public Health. He is the founder and director of the Center for Public Health and Human Rights at Johns Hopkins and the director of the Johns Hopkins Fogarty AIDS International Training and Research Program. He was recently named president-elect of the International AIDS Society of the International AIDS Society and is the co-director of the Johns Hopkins University Center for AIDS Research. Beyrer's research focuses on the burden of HIV and other infectious diseases and the association with human rights, with specific interests in epidemiology among high-risk or marginalized populations, prevention research, and molecular epidemiology.

Chris Collins, MPP

amfAR, The Foundation for AIDS Research
e-mail | website | publications

Chris Collins is the vice president and director of public policy at amfAR, The Foundation for AIDS Research. He holds a Master's degree in public policy from the Kennedy School of Government at Harvard University. Before joining amfAR, Collins was a consultant on policy and communications for domestic and global health organizations. He is the author of Improving Outcomes: Blueprint for a National AIDS Plan for the United States, published by the Open Society Institute. He helped to organize the movement for development of a National HIV/AIDS Strategy for the U.S.; coordinated the Global HIV Prevention Working Group as a consultant with the Bill & Melinda Gates Foundation; and oversaw production of Missing the Target reports produced by the International Treatment Preparedness Coalition (ITPC). Collins is a co-founder of the AIDS Vaccine Advocacy Coalition (AVAC). As an appropriations associate for Rep. Nancy Pelosi, Collins developed the first Congressional legislation designed to provide incentives for the development and delivery of vaccines against AIDS, malaria, and TB.

Kenneth Mayer, MD

Harvard Medical School; Fenway Health
e-mail | website | publications

Kenneth Mayer's clinical research career has focused on the natural history and transmission of HIV in the U.S. and in Asia. He developed some of the very first cohort studies and prevention interventions dealing with the AIDS epidemic. He was trained in internal medicine at Beth Israel Hospital and in infectious diseases and molecular epidemiology at Brigham and Women's Hospital. As the founding medical research director of Fenway Health, he created a community-health research program that has developed an international reputation for its community-based peer reviewed research. He is a visiting professor at Harvard Medical School, an attending physician at Beth Israel Deaconess Hospital, and director of HIV-prevention research there. He was previously a professor of medicine and community health at Brown University and is the principal investigator of the only NIH-funded HIV-Prevention Research Clinical Trials Unit in New England. He is co-chair of an NIAID-funded protocol evaluating a community-based prevention intervention for African American men who have sex with men in 6 U.S. cities. He coauthored the first text on AIDS for the general public (The AIDS Fact Book, Bantam Press, 1983) and has co-edited 5 academic texts, including most recently, The Social Ecology of Infectious Diseases and HIV Prevention: A Comprehensive Approach.

Gregorio Millett, MPH

Centers for Disease Control and Prevention
e-mail | website | publications

Gregorio Millett is a detailee from the U.S. Centers for Disease Control and Prevention (CDC), serving as the senior policy advisor in the Office of National AIDS Policy. In this role, he coordinates the office's policy and research activities, including HIV-prevention policy. He is also the staff lead for the HIV interagency working group that is tasked with developing the National HIV / AIDS Strategy. Before this, Millett was a senior behavioral scientist in the Division of HIV/AIDS Prevention at the CDC in Atlanta. In that capacity, he authored numerous peer reviewed papers that explored racial/ethnic disparities in HIV among men who have sex with men (MSM), correlates of HIV risk behavior among bisexual men of color, and the relationship between circumcision and HIV acquisition among MSM. Before working at the CDC, Millett was a fellow in the HIV/AIDS Bureau of the Health Resources Services Administration (HRSA), a lecturer on lesbian and gay health at Duke University and Bowman Gray schools of medicine, and a board member of the Piedmont HIV Health Care Consortium. Millett holds an MPH degree with an emphasis in community health education from the University of North Carolina at Chapel Hill.

Patrick Sullivan, PhD, DVM

Emory University
e-mail | website | publications

Patrick Sullivan is an associate professor of epidemiology at Emory University's Rollins School of Public Health, and the co-director of the Prevention Sciences Core at Emory's Center for AIDS Research (CFAR). Sullivan's research focuses on HIV among men who have sex with men, including behavioral research, interventions, and surveillance. Previously, Sullivan worked as the chief of the Behavioral and Clinical Surveillance Branch in the HIV Division of the Centers for Disease Control and Prevention, implementing HIV research studies and surveillance systems. He is the principle investigator of NIH-funded studies to determine reasons for black/white disparities in HIV among MSM and to develop and test a couples-HIV-testing intervention for male couples.

Nicholette Zeliadt
Nicholette Zeliadt resides Washington, D.C., where she writes about science for scientists and non-scientists alike. She has a background in biochemistry and nutrition, and a PhD in environmental health sciences from the University of Minnesota. In pursuit of science, she has traveled by ship to the South Pacific Gyre, traversed the Willamette Valley by bike, and encountered 12 of the planet's 13 climatic zones. She has written for Scientific American, Proceedings of the National Academy of Sciences, BioTechniques, and


Presented by

  • The New York Academy of Sciences
  • The Johns Hopkins Bloomberg School of Public Health

Special Guest Speaker:
Thomas Farley, New York City Department of Health and Mental Hygiene


  • New cases of HIV continue to increase among MSM despite available treatment and prevention strategies.
  • MSM comprise 2% of the U.S. population but accounted for 61% of new HIV infections in 2009.
  • HIV is widely perceived to be a manageable chronic infection and is less feared than it was 30 years ago.

The expanding epidemic

The first recognized cases of HIV / AIDS occurred in the early 1980s in gay men and other men who have sex with men (MSM). More than 30 years later, new HIV infections continue to increase in this population worldwide despite decades of research and major advances in prevention and treatment. In the United States, MSM comprise just 2% of the population, yet they accounted for 61% of new HIV infections in 2009 according to the Centers for Disease Control and Prevention. On December 7, 2012, researchers, clinicians, and other professionals at the frontlines of the HIV epidemic met at the New York Academy of Sciences to discuss recent progress toward curbing the spread of HIV among MSM.

HIV incidence among MSM has been stable or increasing in every part of the world that has been studied. (Image courtesy of Stefan Baral)

The Manhattan skyline provided an appropriate backdrop to the meeting, as New York City remains one of the epicenters of the HIV / AIDS epidemic in the U.S., with more than 100 000 HIV-infected residents. Thomas Farley, commissioner of the New York City Department of Health and Mental Hygiene (DOHMH), reported that nearly 67% of the city's new HIV infections occur in MSM; of newly diagnosed MSM, 7 out of 10 are African American or Latino. Farley also acknowledged that while many parameters—new infections, mortality, life expectancy—are improving, the number of new cases of HIV among MSM under the age of 30 has been increasing since 2006. "This is the only population we're looking at where we have an increase in the number of cases in recent years, and that worries me a lot," Farley said.

With the advanced treatments available today, someone newly diagnosed with HIV can expect to have a nearly normal life expectancy. "That's wonderful," Farley said. "But it's also got a problem buried in it, and that is people don't fear HIV in the way they used to." Farley pointed to additional factors that drive the epidemic, including a general sense of fatigue with condoms, denial about risk factors, and the changing nature of the sexual marketplace in the Internet era, where it has never been easier to pick up an anonymous sex partner on short notice.

To combat the epidemic, the DOHMH has distributed approximately 36 million condoms, targeting its efforts toward venues where men are likely to meet male partners. The department has also used media messages that warn about the risks of HIV infection, including the controversial campaign called "It's Never Just HIV," which informed young MSM that HIV infection increases the risks for osteoporosis, dementia, and anal cancer. Farley challenged conference attendees to provide new ideas for messages and prevention approaches.

In the remaining talks, the speakers reviewed recent studies from a special series, HIV in Men Who Have Sex with Men, published in the medical journal The Lancet in 2012. Stefan Baral discussed the worldwide infection rate and the factors that are driving the HIV epidemic among MSM. Gregorio Millett focused on the disparities facing black MSM. Chris Beyrer and Kenneth Mayer explored the prevention, treatment, and care of HIV in MSM. Finally, Chris Collins outlined a strategy for providing MSM with the comprehensive HIV services that will be needed to control this epidemic.

Stefan Baral, Johns Hopkins Bloomberg School of Public Health
Gregorio Millett, Centers for Disease Control and Prevention


  • The HIV epidemic among MSM is expanding globally and is marked by a high HIV burden among young men, rapid spread and clustering within sexual networks, high transmission frequency of multiple HIV variants, and structural-level risks.
  • Black men bear a disproportionate burden of the MSM HIV epidemic: HIV infection rates among black MSM are higher than among other MSM despite comparable risk behaviors.
  • Racial disparities among MSM may be driven by clinical factors and structural inequalities.

Burden of HIV in MSM

Stefan Baral of Johns Hopkins Bloomberg School of Public Health opened the conference with a look at the epidemiological drivers of the HIV epidemic among MSM and the reasons it has continued to grow in most countries. Citing data from 2007 to 2011—including HIV prevalence, incidence, risk factors, and molecular epidemiology—Baral reported that the burden of HIV in MSM was significantly higher than in the general population in all regions. The prevalence of HIV in MSM ranged from a low of approximately 3% in the Middle East and North Africa to a high of approximately 25% in the Caribbean; a strikingly consistent percentage of MSM—between 14% and 18%—lived with HIV in North, Central, and South America, South and Southeast Asia, and sub-Saharan Africa. However, 93 out of 195 countries (nearly half of the countries of the world) had no data on HIV prevalence in MSM for the last 5 years. Baral also noted that during the last 15 years the number of new cases of HIV among MSM has been stable or rising.

Global burden of HIV among MSM. (Image courtesy of Stefan Baral)

Why do MSM bear a disproportionate burden of the HIV epidemic, and why are HIV infections increasing or stable in MSM amid overall decreasing rates of HIV infection worldwide? Individual-level risks such as unprotected receptive anal intercourse, high frequency and number of male partners, ethnicity, and drug use are certainly important, Baral said, but are not sufficient to explain the high rates of HIV among these men. Network-level risks such as larger and lower-density sexual networks and structural risks such as criminalization, stigma, and discrimination in healthcare settings may also be important.

But it is the biology of anal sex and the behaviors associated with it that may be the most potent drivers of the HIV epidemic in MSM. A 2010 systematic review and meta-analysis found the rate of HIV transmission by anal sex to be 1.4% per act, 18 times greater than for vaginal sex, and 40.4% per partner. In addition, MSM can engage in both receptive and insertive anal intercourse, which may enhance the efficiency of HIV transmission in MSM networks compared with heterosexual networks.

Molecular epidemiology studies underscore the importance of biological risk factors. Baral pointed out that the genetic sequences of the HIV variants in MSM are more similar to each other than variants in the general population, suggesting that HIV spreads more quickly in MSM networks than in heterosexual networks. Furthermore, MSM in the U.S. are more than twice as likely as heterosexuals to be infected with multiple HIV variants.

How much smaller would the HIV epidemic be in MSM if anal sex had the same HIV transmission probability as vaginal sex, with all other factors equal? Using a stochastic agent-based modeling approach to simulate HIV transmission in two hypothetical populations—urban U.S. and urban Peruvian—Baral and colleagues predicted that new infections would decline in both populations by 80% to 98% within 5 years. These results further emphasize the importance of the biology of HIV in anal sex and suggest that even substantial changes in behavior, such as a reduction in the number of sexual partnerships, would not significantly impact the HIV epidemic among MSM. The high transmission probability, rate at which MSM become infected, and prevalence of infection in MSM sexual networks suggest that interventions must focus on reducing infectiousness, Baral concluded.

Risks and outcomes in black MSM

Among MSM, black men bear a disproportionate burden of the HIV epidemic. Black MSM represent less than 1% of the U.S. population, yet they accounted for nearly a quarter of new HIV infections between 2006 and 2009. Gregorio Millett of the Centers for Disease Control and Prevention discussed a meta-analysis examining this disparity in the U.S., Canada, and the United Kingdom.

Millett reported that the increased burden of HIV among black MSM is not a result of individual risk behaviors in these men. In fact, young black MSM were tested for HIV as often as other young MSM, were less likely to engage in unprotected anal sex or to use drugs associated with HIV, and reported having fewer male sex partners. However, young black MSM were five times more likely to have HIV and also more likely to be diagnosed with other sexually transmitted infections. In addition, Millett found that HIV-positive black MSM were less likely to know their HIV status or to be using antiretrovirals compared with other HIV-positive MSM. These findings suggest that black MSM may have suboptimal access to healthcare services.

Several factors appear to contribute to HIV disparities among young black MSM: a higher likelihood of childhood sexual abuse, older sex partners, and a younger age at sexual debut compared with other MSM. Young black MSM were also more likely than other MSM to be impacted by structural factors, including low income, low education, incarceration, unemployment, and lack of health insurance coverage. Similar dynamics exist in the United Kingdom and Canada. "Any interventions in clinical settings and interventions that address social and environmental inequalities may have a greater impact in addressing disparities than some of the behavioral risk interventions that we have concentrated on heretofore in the pandemic," Millett suggested.

Worldwide, black MSM are at greater risk for HIV infection than general populations. Millett found that black MSM are 8.5 times more likely to be HIV positive compared with black populations overall and are 15 times more likely to be HIV positive compared with the general population. He also found a shockingly high disparity in HIV prevalence in countries where the general population is not predominantly black: in the U.S. and Canada, black MSM are roughly 72 times more likely to be infected with HIV than the general population; in the United Kingdom, they are 111 times more likely to be infected.

Across Africa, Canada, the U.S., the UK, and the Caribbean, only a few common characteristics correlated with HIV infection in black MSM, including identifying as gay, older age, low income, mixed race ancestry, and a history of sexual abuse. Other characteristics, such as alcohol use, incarceration, sex work, and circumcision, were associated with HIV infection in some regions but not in others.

Millett identified several social inequalities that may help to explain the disparity in HIV infection for black MSM worldwide. Although research has shown that antigay attitudes have declined among Caucasians in the U.S. since 1973, homophobia among blacks has remained largely unchanged. Internationally, antigay stigma is associated with reduced access to prevention and care services, as well as human rights abuses. Furthermore, criminalization of homosexuality is linked with an increase in HIV prevalence among black MSM in African and Caribbean countries.

Chris Beyrer, Johns Hopkins Bloomberg School of Public Health (On behalf of Patrick Sullivan, Emory University)
Kenneth Mayer, Harvard Medical School; Fenway Health


  • The historical approaches to HIV prevention for MSM have failed—more work must be done.
  • With sufficient resources, at least 25% of new HIV infections among MSM could be prevented in the next decade using existing prevention tools.
  • To maximize effectiveness, prevention packages should be multi-faceted and factors such as stigma, discrimination, and criminalization must be addressed.
  • MSM have increased risks for depression, substance use, violent victimization, and childhood sexual abuse, which are correlated with an increased risk of HIV infection.
  • MSM also have increased risks for many STIs, as well as several non-communicable diseases.

Prevention challenges

Prevention efforts have failed to control the HIV epidemic among MSM worldwide. This is particularly difficult because of the high biological risk of transmission associated with anal sex, further compounded by the pervasive stigma and discrimination against MSM. Chris Beyrer of Johns Hopkins Bloomberg School of Public Health reviewed the efficacy of HIV prevention strategies for MSM on behalf of Patrick Sullivan of Emory University, who was unexpectedly unable to attend the conference.

Early in the epidemic, most prevention approaches targeted behavioral risks, such as unprotected anal sex and multiple sexual partners. Unfortunately, these efforts did little to reduce HIV transmission. More recent clinical trials show that biomedical prevention approaches, such as condoms and pre-exposure treatment with antiretroviral drugs, have been more successful in reducing the incidence of HIV infection, but this conclusion is supported by relatively few trials. Virtually all studies are from North America; little is known about the effectiveness of prevention interventions with MSM in other parts of the world.

Categories of HIV prevention strategies for MSM, depicted by efficacy and quality of evidence. (Image courtesy of Patrick Sullivan)

No single intervention strategy is likely to be sufficient to reverse the current HIV epidemic among MSM. Therefore, prevention packages that combine behavioral, biomedical, and structural approaches may be required. Beyrer and colleagues modeled HIV transmission among MSM in the U.S., Peru, Kenya, and India to determine how it might respond to one of three prevention packages: condom promotion, early treatment with antiretroviral drugs after infection, or prophylactic use of antiretrovirals prior to HIV exposure (pre-exposure prophylaxis, or PrEP). These simulations suggested that between 10% and 25% of new infections could be averted using currently available prevention technologies.

Beyrer noted several important obstacles that hinder HIV-prevention programs for MSM. Prejudice, threats, and violence against MSM limit HIV-prevention services; furthermore, many healthcare workers lack the training needed to provide these services, particularly in developing countries. Criminalization of same-sex behavior makes many men reluctant to seek medical care and prevention services and is also used to justify the exclusion of MSM from prevention research. Finally, it is technically difficult and costly to test the impacts of prevention packages, so innovative study designs will be needed.

Despite these significant challenges, Beyrer remains optimistic about the future of combination approaches to HIV prevention. "What we hope is that we're now at something of a turning point in the field because there have been a number of successful interventions," Beyrer said. "We are hopeful that we're going to see some synergistic outputs that will start to really change this trajectory."

Treatment and care challenges

In addition to the challenges associated with preventing HIV among MSM, the unique healthcare needs of these men are a concern. Biological factors place them at increased risk of infection and societal stigma associated with same-sex behavior can lead to depression, anxiety, substance use, and other adverse outcomes. Kenneth Mayer of Harvard Medical School and Fenway Health explored some of the causes and consequences of healthcare disparities in this population.

Mayer reported that some health problems that are prevalent among MSM and others in sexual and gender minorities may stem from early childhood experiences. In many parts of the world, same sex behavior remains stigmatized; youth whose sexual identities deviate from socially-accepted norms are often treated as unacceptable and may experience emotional or physical abuse. To acknowledge their identity carries a risk of losing friends and support from family and community leaders; youth may develop a lack of self-acceptance, low self-esteem, and emotional distress. These problems can lead to adverse health outcomes, which may be compounded by nondisclosure of sexual behavior to healthcare providers, resulting in missed opportunities for screening and counseling.

Mayer also noted that black and Latino youth with same-sex orientation may experience dual stigmas in the U.S.: homophobia within their birth community and racism within the larger society. Such bullying may cause youth to withdraw from school, which can have long-term economic consequences and can lead to homelessness.

Many studies suggest that MSM are at an increased risk for depression, substance use, violent victimization, and childhood sexual abuse; these conditions frequently co-occur and are correlated with riskier sexual practices and increased risk of HIV infection. Despite this, the majority of MSM are not depressed and are not using substances. Although further research is required to understand this resilience, programs that enhance it at earlier ages may lead to effective intervention strategies, Mayer said.

Mayer also emphasized that sexual health refers not only to the absence of HIV or other diseases but also to the possibility of having safe and pleasurable sex. The diverse sexual repertoire of MSM puts them at risk for many STIs in addition to HIV, including rectal gonorrhea and chlamydia, hepatitis B and C viruses, human papilloma virus, herpes simplex virus, syphilis, enteric pathogens, and methicillin-resistant Staphylococcus aureus. Many of these infections are either preventable by vaccination or treatable. However, MSM who are uncomfortable with their sexuality and do not seek care, or are seen by clinicians who do not ask appropriate questions about sexual behaviors, may not be screened or treated and are more likely to transmit infections.

MSM are also susceptible to non-communicable medical conditions. Some individuals attempt to conform to cultural ideals for body image and weight, while others are prone to overeating due to depression. In addition, MSM may experience medical complications associated with the use of substances such as cigarettes, inhaled stimulants, and alcohol. Finally, MSM may experience unique aging issues because they often age alone, due in part to a lack of societal acceptance of non-traditional families.

Mayer closed by recommending that healthcare professionals be trained to recognize the diversity of MSM and their different health conditions and to provide culturally-competent care. Providers need to consider the whole person, including mental health, relationships, substance abuse, HIV status, and other STIs.

Chris Collins, amfAR, The Foundation for AIDS Research
Panel Moderator:
Chris Beyrer, Johns Hopkins Bloomberg School of Public Health


  • Gay-advocacy movements have been at the forefront of AIDS advocacy since the beginning of the epidemic and will continue to be important.
  • The unique nature of the HIV epidemic among MSM needs to be recognized, and MSM must be included in global surveillance and research efforts.
  • Individual-level behavioral change is necessary but insufficient to tackle HIV in MSM; biomedical and behavioral change-interventions will not achieve optimal results unless stigma and discrimination are addressed.
  • Messages about HIV for MSM need to be diverse and carefully crafted to avoid further stigma and discrimination.

A call to action

MSM bear a disproportionate burden of the global HIV epidemic, yet continue to be understudied and excluded from HIV services. To gain control of the global HIV epidemic, action must be taken on the sub-epidemic in MSM. Chris Collins of amfAR, The Foundation for AIDS Research outlined a strategic framework for expanding HIV prevention, treatment, and care services for MSM.

Collins began by examining the legacy of gay- and MSM-activist movements, which have been at the forefront of AIDS advocacy and will continue to be powerful driving forces for future change. Such efforts have advanced research, stimulated policy changes, and enhanced service delivery. Despite these successes, activists face many challenges, including threats of violence, stigma, and other forms of backlash.

The HIV epidemic in MSM must first be acknowledged as a health threat and investigated. MSM must be included in research, provided with support and services, and involved in making decisions about health programs, Collins said. Moreover, improved global surveillance is needed: more than 50% of countries lacked data on HIV prevalence in MSM in 2011, particularly in parts of the Middle East and Africa, where criminalization of same-sex behavior can complicate epidemiological assessments.

Global surveillance of HIV in MSM. (Image courtesy of Chris Collins)

It is also necessary to expand the package of services available to MSM to include HIV testing and treatment, condoms and appropriate lubricants, and mental health and substance abuse services. These services often focus on individual-level behavior change, which is critical but insufficient to tackle the HIV epidemic among MSM, Collins said. Estimating the number of HIV infections that could be averted by scaling-up a variety of HIV-prevention services, Collins and colleagues concluded that the largest impacts could be realized by increasing investments in low- and middle-income countries and by reducing HIV drug prices in high-income countries. They also estimated that an investment of $134 million in the coming year—a small fraction of the funds spent on HIV / AIDS annually—would cover the costs of condoms, lubricants, and distribution efforts that could avert 25% of new global HIV infections in MSM in the next 10 years.

Collins noted that even the best biomedical and behavior interventions cannot succeed without addressing the stigma and discrimination affecting MSM. He asserted that arguments rooted in culture, tradition, or religion cannot override the universal human rights to bodily security and sexual health. In 2011, the Global Commission on HIV and the Law found that laws criminalizing consensual same-sex activity undermine the prevention and treatment of HIV in MSM. The commission called for decriminalization of same-sex activity, accompanied by measures to prevent violence against MSM, to enforce laws that prohibit discrimination, and to remove barriers to HIV and other health services. Racial disparities in HIV infection must also be addressed.

Collins concluded by outlining priorities for research, including the prevalence of HIV in MSM; the cost-effectiveness of various prevention, treatment, and care programs; the efficacy of rectal microbicides; and the effect of stigma and homophobia on the risk of HIV infection. He also described a four-part strategy to improve the response to HIV in MSM: reduce homophobia and decriminalize same-sex behavior to overcome barriers to care; expand access to evidence-based services and scale-up prevention and treatment programs; improve the use of donor funds and resources; and improve outcomes by setting targets, measuring progress, and holding stakeholders accountable. "I think that by working together, demanding equity, and recognizing our diversity, we can achieve an AIDS-free generation for gay men and in the process advance our rights and the rights and health of other people," Collins said.

Panel discussion

The discussion about how to tackle the HIV epidemic in MSM continued in the interactive panel discussion, moderated by Chris Beyrer of Johns Hopkins Bloomberg School of Public Health and featuring Stefan Baral of Johns Hopkins Bloomberg School of Public Health, Chris Collins of amfAR, The Foundation for AIDS Research, Kenneth Mayer of Harvard Medical School and Fenway Health, and Gregorio Millett of the Centers for Disease Control and Prevention.

The panelists discussed the need to create appropriate messages about HIV for MSM. Because of the great diversity within the MSM population, Mayer called for equally diverse messages. "Some approaches may work with gay-identified people, and others have to deal with people who are not identified," he said. Beyrer lauded the messaging efforts of the Microbicide Trials Network, which promotes rectal microbicides as an intervention for everyone who practices anal sex—the per-act and per-partner risks of contracting HIV through anal sex are the same across genders for receptive partners. Collins said that he would like to see messaging campaigns that show people living with HIV encouraging others to protect themselves, get tested frequently, and get treatment. "If more people can come out about living with HIV in a positive way, that can be catalytic in terms of addressing stigma [and] driving demand for healthcare services and other things," he said.

Beyrer also pointed to social media as a potential tool for interventions. Baral echoed this, noting that social media has been particularly useful for delivering adherence reminders and surveys. While Baral thought that it would be difficult to deliver meaningful intervention strategies in this format, he acknowledged that it may be the only way to communicate with some populations until clinics and societies are seen as safe and accepting.

Millett elaborated on how the U.S. is addressing the structural and clinical risk factors in the black MSM population. For example, some clinics have reported higher rates of viral suppression when patients are provided with financial or other incentives to adhere to therapy. He also suggested leveraging social networks, citing studies that report fewer new diagnoses when MSM are asked to bring members of their sexual or friendship networks to get tested, as compared with when MSM come alone. Millett also recommended addressing other factors that are often not considered a part of public health, such as education, housing, employment, and urban development: "HIV is not just about health, it's about all these other issues that impinge upon health and make people at greater risk for HIV," Millett said. "I think we need to start…thinking outside of the box [about] some of the other factors that might be impinging upon these disparities and figuring out what types of interventions might be appropriate."

How can we scale-up HIV treatment, prevention, and care services to reach larger numbers of MSM?

Which interventions can effectively address HIV among MSM, given the evidence that the epidemic may be driven primarily by biological factors rather than by risk behaviors?

What are the most appropriate intervention packages for each setting and sub-population of MSM?

How can diverse MSM populations be engaged?

How do we reach those MSM who are most at risk for HIV? What messages would they respond to, and what types of services do they need?

How do we track the delivery, utilization, and efficacy of services for MSM?