HIV treatment prevents transmission in couples

HIV treatment prevents transmission in couples


Despite not having a cure, there have been tremendous advances in HIV prevention and treatment over the 35 years of the global HIV epidemic. But one of the questions has been: in a couple (homosexual or heterosexual), if one person is HIV positive and the other HIV negative, how safe is it to have sexual relations?

Couples with one partner HIV positive and one HIV negative are referred to as “HIV-different” or “HIV-discordant” couples. And now, the question about the safety of sexual relations in these couples has been answered by a long-term study just published in the British medical journal The Lancet.

The European HIV study

This first phase of the study ran from 2010 to 2014, and included 888 couples. Most were heterosexual couples, recruited from 75 clinical sites in 14 European countries. Each couple had one partner who was HIV positive, but who was receiving anti-retroviral therapy (“cocktail”) that effectively lowered their virus count to “undetectable” (or less than 200 copies/ ml.). The couples were not using condoms during sex.

The results were very encouraging. The data showed that the risk of transmission from the HIV positive partner the HIV negative partner was zero. Note however that there were 11 HIV negative people who turned positive during the years of the study.

Importantly, though, the researchers performed genetic analyses of the HIV virus in each of those couples. These genetic studies showed that the people who turned positive were contaminated by a different genetic strain of the virus. Meaning, they received the virus from sexual relations outside their primary relationship, and not from their partner. Apparently when partners “strayed” from their primary relationship, and without proper condom protection, they were vulnerable to infection by someone who was HIV positive but whose virus level was NOT undetectable.

The second part of the study ran from 2014 to 2017, and included only homosexual couples (782 couples). The results were the same as the first phase of the study. There was a zero rate of transmission of the virus from the HIV positive partner to the HIV negative partner. There were a few HIV negative men who converted to positive, but again genetic testing of their virus proved that the virus was received from a sexual act outside the primary relationship.

The message

According to a leader of the research, Professor Alison Rodger from University College, London “Our findings provide conclusive evidence for gay men that the risk of HIV transmission with suppressive ART is zero. Our findings support the message…that an undetectable viral load makes HIV untransmittable.”

This is very reassuring news for couples in a sero-different relationship. However, note that the HIV positive partner needs to take his anti-retroviral medication faithfully, with regular blood testing to ensure that their viral load remains undetectable.

Also the message is that if the HIV negative partner has sexual relations outside the primary relationship, that they can be infected by that outside person if safe sex practices (condoms) are not followed. Finally, anti-retroviral therapy does not prevent the spread of other infectious diseases such as syphilis and gonorrhea. Only condoms will prevent those infections.

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See also in ProcuraMed:

Update on PrEP daily to prevent HIV infection

Near normal life expectancy for HIV positive people

Esta postagem também está disponível em: Portuguese (Brazil)

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