By Liz Highleyman

While the total estimated global number of new HIV infections per year has declined slowly since the 1990s, according to a recently released report from the United Nations Program on HIV/AIDS (UNAIDS) and the World Health Organization, the incidence of new infections among men who have sex with men (MSM) appears to be rising again after previously leveling off or falling.

HIV/AIDS advocates expect the Centers for Disease Control and Prevention (CDC) to soon announce data showing that the overall rate of new infections in the U.S. is significantly higher -- perhaps as much as 50% higher -- than the steady 40,000 estimated annual cases the agency has been reporting for the past several years.

According to the Washington Blade, CDC officials have reportedly told leaders of AIDS advocacy groups that the revised total could be around 60,000 new cases. It is not clear whether the new figure reflects an increase in the number of people becoming infected, or rather more extensive testing and more accurate reporting.

“We are developing new incidence estimates and CDC and our partners are very excited about this, because this is finally providing us with information on where the epidemic is located,” said Kevin Fenton of the CDC’s National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention during a World AIDS Day webcast on November 16.

“We have some different estimates from what had been published previously, and it’s very important that CDC has robust external scrutiny of these estimates in order to feel absolutely confident that we are both providing the correct estimates and that our methodologies are robust as well,” he continued. “So CDC has been working with peer-reviewed journals to have the methodologies and the estimates externally reviewed, and we’re looking forward to publishing the results in the very near future.”

While the relative proportion of women and heterosexuals becoming infected with HIV has risen steadily over the course of the epidemic, MSM -- especially young men and men of color -- still account for a large number of new infections.

“Gay and bisexual men, or men who have sex with men, still continue to bear the brunt of the HIV epidemic in the United States today,” Fenton said. “We estimate at CDC that about 67%, nearly two-thirds, of new diagnoses of HIV/AIDS are occurring among gay and bisexual men, or men who have sex with men.”

In San Francisco, the annual number of new HIV infections has plateaued after falling consistently for several years. Willi McFarland of the San Francisco Department of Public Health said that officials expect annual HIV incidence to hold steady at around 1000 new infections per year, leading him to describe the disease as “endemic” rather than “epidemic” in the city. In San Francisco, MSM accounted for about 75% of all new HIV cases in 2006.

“We need to encourage HIV testing among young MSM and, in fact, all MSM. We need to encourage those who have tested HIV positive, and ensure that those MSM [are] receiving proper therapy,” Fenton added. “Finally, we need to encourage those MSM who are HIV negative to stay negative, and [emphasize] that there is a benefit to remaining HIV negative, even today, 25 years into the epidemic.”

A Re-emerging Epidemic

In the November 28, 2007, issue of the Journal of the American Medical Association, 3 international public health experts -- Harold Jaffe (former director of the CDC’s National Center for HIV, STD and TB Prevention, now at the University of Oxford), Ronald Valdiserri (chief consultant for the U.S. Department of Veterans Affairs Public Health Strategic Health Care Group), and Kevin De Cock (WHO’s Director of HIV/AIDS) -- presented an overview of the “re-emerging HIV/AIDS epidemic” among MSM.

Although MSM first brought HIV/AIDS to the world's attention, and were the first to promote risk reduction strategies, they wrote, “prevention efforts for MSM appear to have faltered.”

According to the authors, the number of HIV/AIDS cases among MSM increased by 13% in the U.S. between 2001 and 2006, and by 55% in Europe between 1998 and 2005. They also pointed to an increase in syphilis cases as evidence of the increasing frequency of unprotected sex.

While dramatic changes in sexual behavior in the early years of the epidemic resulted in part from fear of the disease -- leading gay men to develop “a collective will to survive that embraced safer sex norms” -- the authors said that today, “AIDS is simply not as frightening as it was before highly active antiretroviral therapy (HAART) became available.”

“Younger MSM have largely been spared the visible devastation of untreated HIV infection,” they continued. “Most U.S. residents no longer view AIDS as a major health threat.”

Further, they noted, “Lack of awareness of HIV infection status is a likely reason for continuing high-risk behaviors in MSM.” A recent study of more than 5000 young MSM in 6 U.S. cities, for example, found that 10% of the men were HIV positive, of whom 77% were unaware they had the virus; nearly 60% of men who were unaware they were HIV positive considered themselves to be at low risk.

This lack of awareness and inaccurate perception of current HIV status and level of risk, the authors said, would “weaken the risk-reduction strategy of serosorting, in which partners who believe they have the same serostatus engage in unprotected sex.”

To reduce the rate of new infections, biomedical prevention methods -- such as HIV vaccines, microbicides, pre-exposure prophylaxis, and circumcision -- may one day augment behavioral approaches, but at this time these are experimental. (While circumcision has been associated with lower HIV infection rates in Africa,this has not been demonstrated in the U.S.)

“In addition to re-energizing the call for safer sexual behaviors, new leaders must call for the end of stigma toward MSM, which may mitigate the internalization of homophobia leading to sexual risk behavior,” the authors wrote. “This need is particularly critical within racial and ethnic minority MSM communities that bear the stigma of homosexuality along with the discrimination faced by these minorities. Political leadership is also needed to advocate for legal domestic partnerships as a way to promote stable, longer-term MSM relationships.”

They continued by describing some potential HIV prevention pitfalls: “In an effort to increase the effect of a behavioral intervention, it may be tempting to exaggerate the danger of the condition to be avoided. However, such tactics are morally questionable and may ultimately be counterproductive. It may also be tempting to introduce legal penalties for unsafe sex; however, with the rare exception of penalties for intentional exposure to HIV, this approach is unacceptable in free societies. Although emphasizing individual and community responsibility may seem overly moralistic, establishment of community norms of safe behavior can play a key role in addressing the MSM HIV/AIDS epidemic.”

Despite the current challenges, “advances can occur through open discussion, increased HIV testing, funding to develop and implement evidence-based public health interventions, leadership from the gay community and public health officials, and recognition of the role of personal action,” the authors concluded. “Failure to address these difficult issues implies that the HIV/AIDS epidemic in MSM must be accepted as inevitable; this cannot be allowed to happen. The tragedy of the epidemic for an earlier generation of MSM must not be repeated.”

11/30/07

Sources

CDC. World AIDS Day webcast. November 16, 2007 (transcript available at www.aids.gov/podcast/aidsday_webcast.html).

L Chibbaro. Gov’t to Report Alarming Spike in HIV. Washington Blade. November 14, 2007.

MS Bajko. SF's HIV Rate Flat-lines, STDs Drop. Bay Area Reporter. November 15, 2007.

HW Jaffe, RO Valdiserri, and KM De Cock. The Reemerging HIV/AIDS Epidemic in Men Who Have Sex With Men. Journal of the American Medical Association 298(20): 2412-2414. November 28, 2007.