An international team of researchers has discovered a way that may make it possible to slow the progression of HIV virus in women who also suffer from genital herpes. The investigators found that treating such women with an inexpensive drug for genital herpes reduced the amount of AIDS virus in their blood. VOA's Jessica Berman reports.

Experts say that between 50 and 90 percent of people who are HIV-positive in Africa are also infected with a virus that causes genital herpes. According to the experts, genital herpes, which causes blister-like sores, acts as a gateway for the AIDS virus to enter the body.

Researchers have also known for a while that when the two viruses interact, they cause people to get sick and die of AIDS sooner than if they were infected with HIV alone.

Lawrence Corey is a leading AIDS researcher at the University of Washington Virology Division in Seattle.

"Genital herpes increases the replication rate of HIV in the body," said Lawrence Corey. "And if you treat genital herpes with an antiviral that's directed just against the herpes simplex virus, and not against HIV, you actually can decrease the viral load or the amount of viral load that's circulating in the blood [plasma] by a significant amount."

Corey, who did not participate in this study, says the drug valacylovir, usually used to treat gential herpes, was as effective in suppressing the levels of HIV in the blood as the old AIDS drug AZT.

The study was conducted in Burkina Faso by a team of French, British and African researchers. It involved 140 women infected with both HIV and genital herpes who were not being treated for either disease. Half of the group received valacyclovir, the other half were given dummy pills for three months.

At the end of the trial, there was a dramatic reduction in the amount of HIV in the blood and vaginal secretions of the women who took the valacyclovir, which is manufactured by GlaxoSmithKline.

The investigators say reductions in HIV were greatest among those women who stayed on the drug the longest

The results of the study were published in the New England Journal of Medicine.

In a commentary in the Journal, Corey says more research is needed to confirm the benefits of treating genital herpes in people with HIV.

In the meantime, he says, clinicians ought to waste no time diagnosing and treating their HIV patients for this and other venereal diseases.

"One of those clinical benefits might be to prolong the time that you are asymptomatic and prolong the time that you need antiretroviral therapy," he said. "Or for those people that are not doing that well on antiretroviral therapy, prolong the time that antiretroviral therapy is effective."

The experts hope that simple strategies like treating genital herpes will help reduce the transmission of HIV in developing countries, where costly anti-AIDS drugs are out of reach for many people.