Among people with HIV who have viral loads higher than 1,500, the small proportion of those who have sex that poses a risk of transmitting the virus often have high viral loads, aidsmap reports.

A higher viral load makes an individual more likely to transmit the virus in the context of condomless intercourse.

Publishing their findings in Sexually Transmitted Infections, researchers conducted a study of 1,315 people with HIV who had a viral load above 1,500 and who were receiving care at six university-affiliated U.S. hospitals as part of a study looking at an intervention to improve control of the virus and retention in HIV care. The participants were given a computer questionnaire asking about their sexual behavior during the previous two months.

Sixty-one percent of the participants were taking antiretroviral (ARV) treatment. Thirty-eight percent were men who have sex with men (MSM), 32 percent were heterosexual men and 30 percent were women. Sixty-two percent were Black, 18 percent were white and 18 percent were Latino.

Thirty-seven percent reported engaging in anal or vaginal sex during the previous two months; 60 percent of that group reported always using a condom. Just under 30 percent of those reporting recent intercourse said they had condomless sex only with other HIV-positive partners.

Fourteen percent (68 people) of the group reporting recent sex said they had condomless sex with partners who were HIV negative or whose status they did not know. Sixty-three percent (43 people) of these individuals had viral loads above 10,000, and 31 percent  (21 people) had viral loads above 50,000.

To read the aidsmap article, click here.

To read the study abstract, click here.