A third of gay men with HIV are unaware that they are infected yet an increasing number of them are engaging in unsafe sex with other men, a study has found.
The scientists who carried out the research have warned that the high level of risky behaviour among HIV-positive men - whether they have been diagnosed or not - is a serious public health concern. The findings, published today in the journal Sexually Transmitted Infections, will re-ignite the debate over whether the safe-sex message has lost its impact among gay men.
The survey of more than 8,000 men visiting gay bars, clubs and saunas across London revealed an increase in unprotected sex since the study of gay men's behaviour began nearly 10 years ago. The proportion engaging in risky sexual behaviour increased from about 30 per cent in 1996 to 42 per cent in 2000, said the researchers, from the Royal Free and University College Medical School and the Central Public Health Laboratory.
Saliva samples taken from 1,206 men who took part in the survey were tested anonymously for HIV and about one in nine turned out to be antibody-positive. About a third of those infected with the virus - 43 individuals out of the 132 who were HIV-positive - were undiagnosed, Julie Dodds and her colleagues Danielle Mercey and Ann Johnson said.
"Homosexual men continue to report increasing levels of unprotected anal intercourse. HIV prevalence is high in this group, with many infections remaining undiagnosed," the researchers said. "The high level of risky behaviour in HIV-positive men, regardless of whether they are diagnosed, is of public health concern in an era when HIV prevalence, anti-retroviral resistance and STI [sexually transmitted infections] incidence are increasing."
About 16 per cent of the men who reported having a sexual relationship with partners of the same HIV status were incorrect about their diagnosis or could not be certain about it. Overall the study found that 10.9 per cent of the socially active gay men in London who took part in the survey were HIV-positive, as determined from tests for the presence of viral antibodies in saliva samples.
"High levels of unprotected anal intercourse continue to be reported by both HIV saliva antibody-positive and negative men, and the potential for onward transmission of HIV and increasing prevalence is a major public health concern," the researchers said.
Latest figures from the Health Protection Agency revealed a 20 per cent increase in people being diagnosed with HIV during 2003. So far there have been 5,047 new cases of HIV reported for 2003, compared with 4,204 for the same period in the previous year.Reuse content