MEXICO CITY (Reuters) - Younger men who binge drink and abuse drugs are the gays and bisexuals most likely to transmit HIV to others, and prevention programs should be developed to target them, U.S. researchers said on Thursday.
The study, presented at an international AIDS meeting in Mexico City, also helps explain why the AIDS epidemic is starting to grow again among U.S. homosexuals.
"When one drinks or uses other substances, inhibitions are lowered, making people more likely to engage in risky behavior like unprotected sex. This is particularly true for young people, who often take risks without thinking about the consequences," said Dr. Kenneth Mayer, an infectious disease specialist at Brown University in Rhode Island.
Gay and bisexual men account for about half of all new HIV infections in the United States.
The researchers studied 200 HIV-positive gay and bisexual men in the United States. They found that 57 percent were getting treatment and half met the criteria of "high-risk HIV transmitter," defined as having engaged in unprotected anal intercourse over the last six months with partners who were either HIV positive or whose HIV status was not known.
Three-quarters of the men were white and more than half were college-educated.
Nearly a quarter of the men said they had consumed five or more alcoholic drinks in a day at least once in the previous three months and 65 percent used drugs such as methamphetamine. About 12 percent had been diagnosed with a sexually transmitted infection within the past year, according to the study.
Mukesh Kapila, special representative of the secretary general at the International Federation of Red Cross and Red Crescent Societies, said HIV prevention programs must target each new generation.
"Within the community of men who have sex with men, the new generation would not have been through the 1980s and 1990s and they wouldn't have the high levels of awareness that the previous generations have. And (they have) the feeling perhaps that treatment is available, that maybe it's not such a fatal condition anymore," Kapila told Reuters in an interview.
"What it shows is the task of prevention is a permanent one. Every generation has to start (learning) again."
Editing by Xavier Briand