IAS: Diagnosis during primary infection reduces risky sex

Being diagnosed with primary (sometimes called acute) HIV infection can lead to a significant decrease in sexual behaviour that involves a risk of HIV transmission, according to a small American study presented as a poster to the recent International AIDS Society Conference on HIV Pathogenesis, Treatment and Prevention in Sydney.

It is thought that as many as 50% of all HIV transmissions originate from people who have been recently infected with HIV themselves. This is because HIV viral load is particularly high in the first couple of months following HIV seroconversion.

US investigators wanted to see if being diagnosed with primary HIV infection was associated with a decrease in HIV risk behaviour. They therefore examined the sexual behaviour of individuals diagnosed with primary HIV infection in the eight weeks before and after their HIV diagnosis. A total of 32 recently infected individuals were recruited to the study, which involved a qualitative interview and structured questionnaire. Data from 21 individuals were presented to the Sydney conference. Individuals were recruited in Los Angeles, New Haven, New York, Providence, San Diego and San Francisco and all but three were gay men.

Individuals were interviewed about their sexual behaviour immediately prior to their infection with HIV within four weeks of their diagnosis with primary HIV infection. They were interviewed about their subsequent sexual behaviour eight weeks later.

Half of the participants were white, 47% were aged between 30 and 39 years, two-thirds had at least some college education, 62% were single, and 81% said they were gay, with a further 6% saying they were bisexual.

Unprotected anal sex with partners met on the internet was the principal reason for HIV infection. In the eight weeks before the diagnosis of primary HIV infection, individuals reported an average of nine sexual partners. The majority of these partners were either known to be HIV-negative (mean, four), or perceived to be HIV-negative (mean, four), with a mean of one known to be HIV-positive.

But in the eight weeks after the diagnosis of primary HIV infection, the average number of sexual partners fell to four, with the majority of partners (mean, 2.5) reported to be also HIV-positive.

There was also a significant decrease in the amount of unprotected sex reported. In the two months before diagnosis, individuals reported a mean of six episodes of unprotected anal or vaginal sex with HIV-positive partners and a mean of six episodes of unprotected penetrative sex with HIV-negative partners. Immediately following diagnosis, however, the mean number of instances of unprotected anal or vaginal sex with HIV-positive partners fell to five, and no unprotected penetrative sex with HIV-negative partners was reported.

The qualitative interviews revealed that individuals adopted a range of behaviours likely to reduce the risk of onward HIV transmission.

One strategy was sexual abstinence, with a gay man telling the investigators of his complete lack of interest in sex, “not even masturbation.” A heterosexual man also reported initial abstinence, saying, “I don’t want to infect nobody.”

Another strategy was reducing the number of sexual partners. One gay man said, “in the two months before [diagnosis] I had sex with three people. Now I’m just with my partner. I don’t want to take a risk and hurt anybody else.”

There was also evidence of serosorting – the deliberate selection of other HIV-positive partners. One gay man told investigators, “I won’t have sex with people who are negative. Whereas before it was the other way round.” Another gay man said, “since my diagnosis…I haven’t played with anyone negative…my new partners are also positive. So I don’t have to worry about giving them HIV. Most other stuff can be cured.”

Condom use also increased, with one gay man saying that the recommendation of his doctor lead him to use condoms with other HIV-positive men. A heterosexual woman reported that she shifted from sexual abstinence to condom use, saying, “at first I had no sex…but then I told my partner who was very accepting… we now always use condoms.”

Testing for HIV during primary infection can serve as a “behavioural intervention” conclude the investigators, “as it appears to promote an immediate decrease in sexual behaviour, number of sexual partners, and serodiscordant partnering as well as increased condom use.” The investigators add, “attempts to diagnose HIV in a timely manner could decrease HIV incidence and better connect clients with care and support services.”