June 26, 2008 -- HIV diagnoses in the U.S. are on the rise among men who have sex with men, especially among males aged 13-24.
That news comes from the CDC, which tracked HIV/AIDS diagnoses reported by 33 states from 2001 to 2006.
During that time, those states had 214,379 HIV/AIDS diagnoses. Men who have sex with men account for almost half -- 46% -- of those diagnoses.
Every year from 2001 to 2006, HIV diagnoses among men who have sex with men rose by 1.5% overall. But that figure doesn't tell the whole story.
The youngest men, those aged 13-24, had the steepest estimated annual increase -- 12% in HIV/AIDS diagnoses. And the increase was higher -- 15% per year -- for African-American men aged 13-24 who have sex with men, compared to 9% among white and 8% among Hispanic men of the same age who have sex with men.
Men who have sex with men were the only high-risk group to show an increase in HIV diagnoses during 2001-2006. HIV diagnoses dropped during that time among heterosexuals who have high-risk sex, injection drug users, and men who are injection drug users who also have sex with men.
The findings appear in the CDC's Morbidity and Mortality Weekly Report.
The CDC's new report is about HIV/AIDS diagnoses, not infection rates. Many people with HIV don't know they're infected.
But the new HIV/AIDS diagnosis statistics may be a red flag that HIV infection is rising among men aged 13-24 who have sex with men.
"Because these men probably have not been sexually active for a very long period of time, there's reason to believe that these diagnoses probably represent fairly recent infections and so it's an indication that infections may be increasing in this population," Richard Wolitski, PhD, acting director of the CDC's division of HIV/AIDS Prevention, tells WebMD.
Increased HIV testing probably doesn't explain the trend, according to the CDC.
The increase in HIV diagnoses among young men who have sex with men may partly be due to "sero-sorting," in which men who have sex with men choose monogamous relationships with partners whom they believe have the same HIV status as them. But they may be mistaken about their HIV status.
Some men, especially younger men, have "begun to shift from using condoms consistently as their primary risk-reduction strategy to sero-sorting," says Wolitski. He explains that while sero-sorting works theoretically in a monogamous relationship, it's risky in the real world because some men may be HIV positive and not know it.
"Most men who have sex with men have been tested at least once before," says Wolitski. He notes that in a 2005 CDC study conducted in five U.S. cities, 84% of the men who were HIV positive and didn't know it had been tested at least once before, but 58% hadn't had an HIV test in the past year.
"CDC recommends that all sexually active men who have sex with men be tested for HIV on at least an annual basis, and we recommend that [men who have sex with men] who are engaging in risky sexually practices be tested more frequently," says Wolitski.
June 27 is National HIV Testing Day, notes the CDC, which has posted a list of HIV testing sites online.
"It's not the case that men who have sex with men no longer care about getting HIV or are intentionally seeking HIV infection," says Wolitski. "The vast majority of men who have sex with men still are actively taking steps to avoid contracting HIV, and we know that HIV prevention interventions continue to be effective for this population."
HIV prevention messages still work, but it can be hard to reach males as young as 13, says Wolitski, who sees the Internet as one potential way to get HIV prevention messages to young men.
Growing up decades after HIV/AIDS started may also be a factor.
"There seem to be some additional challenges in trying to introduce regular condom use among younger men, perhaps because they haven't had the experience of seeing the impact of the AIDS epidemic in the earlier years of the epidemic," says Wolitski.