IAS 2015HIV-negative men who have sex with men (MSM) living in Seattle as well as Australia are taking their partners’ viral load, treatment or HIV testing history into account when making decisions about condom use, aidsmap reports. Researchers presented findings from two different studies looking at so-called sero-adaptive behaviors at the 8th International AIDS Society Conference on HIV Pathogenesis, Treatment and Prevention in Vancouver, British Columbia.

Researchers presented preliminary findings from the ongoing Opposites Attract study of 147 mixed-HIV status gay couples in Australia, Brazil and Thailand. Almost all the Australian HIV-positive men were on treatment and had an undetectable viral load. The researchers found that two-thirds of the Australian couples reported having condomless intercourse together. Those HIV-negative men who believed their partner had an undetectable viral load were 3.2 times more likely to report having sex without a condom. Those who believed that HIV treatment could lower transmission risk were also more likely to have condomless sex.

The men in Brazil and Thailand did not apparently consider viral load when making decisions about condoms.

Findings were also presented from a study of 1,011 HIV-negative and 203 HIV-positive MSM attending a Seattle sexual health clinic in 2014 and 2015. Eighty-six percent of the HIV-negative men said that they had asked at least one HIV-positive partner about his treatment and viral load status. Two-thirds of these men used this information to make sexual decisions; this subgroup was more likely to have condomless intercourse than the rest of the participants.

Eighty-six percent of the HIV-negative Seattle men asked about the timing of the most recent HIV test of their last partner who said he was HIV negative. More than half of these partners said they had gotten tested within the previous three months. The HIV-negative men in the study were more likely to report condomless sex if their partner had had a recent HIV-negative test result; many reported the timing of the test affected their condom use deliberations.

To read the aidsmap article, click here.