ARVs may Prevent HIV Transmission by 90 Percent. 7/5/10

The chance of transmitting the virus to each other is reduced by at least 90% if the HIV-positive partner is on anti-retroviral therapy (ARVs).

AllAfrica

Kampala — A study of HIV transmission between long-term HIV discordant couples in Africa has found that the chance of transmitting the virus to each other is reduced by at least 90% if the HIV-positive partner is on anti-retroviral therapy (ARVs).

A discordant couple is where one partner is positive and the other is negative. This was in a study whose results were reported at a Conference in Cape Town recently.

During the study, there was one transmission from a partner who was taking ARVs. The presenter, Deborah Donnell, said this indicated that discordant couples should keep having protected sex, even when the HIV-positive partner was on treatment and with a high CD4 count.

The other important finding from this study was that untreated partners with CD4 counts under 200 were five times more likely to transmit HIV than those with CD4 counts over 350, strengthening the case for extending ARVs to all people with low CD4 counts.

The study, consisted of 3,381 discordant couples from Uganda, Kenya, South Africa and Zimbabwe. About 30% of partners had reported having unprotected sex with their main partner in the previous month. None were on ARVs.

CD4 counts were taken every six months, HIV tested and ARVs were given. During the study, 349 people, about 10%, started taking ARVs. Approximately half of them had CD4 counts under 200 and one-third between 200 and 350.

There were 151 new HIV infections in the study. HIV viruses were sequenced to show the source of the infection and 108 (28.5% of infections) were proved to have came from someone who was not the primary partner.

Only one of the transmissions came from a partner taking ARVs. This meant the relative risk of transmission from a partner taking ARVs, when adjusted for time on study and CD4 count, was 0.08; a 92% reduction in HIV transmission.

At the moment therefore, ARVs and using condoms is one of the leading HIV prevention technologies we have. If only we could work on increasing accessibility.