Opening session of the International AIDS Conference in Vienna Austria, 18 July 2010

South African researchers have made a scientific breakthrough in the fight against AIDS with a vaginal gel that significantly reduces a woman's risk of being infected with HIV, the virus that causes AIDS.  Experts say the gel could be a revolutionary prevention tool, empowering women to protect themselves against partners who refuse to use condoms.

Since the AIDS epidemic began nearly 30 years ago, scientists have been searching for a vaginal microbicide that women could use to protect them from contracting HIV.

Now South African scientists Salim and Quarraisha Abdool Karim with the Center for the AIDS Program of Research in South Africa (CAPRISA), say their clinical trials on 889 South African women show great promise.  USAID helped to fund their study.

Quarraisha Abool Karim spoke with VOA about the findings.

"What we found in the study was that that women who were assigned to the tenofovir gel arm had 39 percent protection against getting infected compared to the placebo group," Dr. Abdool Karim said. "Those women who used the gel more than 80 percent of the time when they had sex, as we advised them to, had 54 percent protection.  So that is quite a powerful effect."

Dr. Abdool Karim said the studies are proof of a concept, but that more trials are needed before the gel could come to market.  But the hope is that it could be available within two to three years.

UNAIDS Executive Director Michel Sidibe is among the AIDS activists and experts celebrating the promising news.

"First let us say we need to celebrate," Sidibe said. "In 30 years of fighting HIV/AIDS it is the first time that we can talk about a prevention revolution."

About 33-million people worldwide are infected with the HIV virus - about half of them are women.  In Africa, more than 60 percent of new HIV infections are acquired by women and girls.

The new gel contains tenofovir, an antiretroviral drug that prevents HIV from growing in human cells.

Women apply the gel up to 12 hours before sexual intercourse and a second time as soon as possible within 12 hours afterwards.  Michel Sidibe says the simplicity of the gel will be the key to its appeal and effectiveness.

"This simplification is the revolution part," Sidibe said. "I called for a prevention revolution and I am so convinced that to fight this epidemic we need prevention, prevention and prevention."

Dr. Abdool Karim says there is still a lot of work to be done before women around the world will have access to the gel.

"Now we have to work on what is the next step," Dr. Abdool Karim.  "The next step is how do we get this into women's hands, what is the next set of studies we need to be doing to get us closer to that?  So until it is in women's hands our job is not done, and until we have eradicated [the] virus in this world we have lots to do."

The South African study also found that in addition to reducing HIV infection, it also reduced the rate of infection of herpes simplex-2 by 51 percent.  Women who have the herpes virus are more than twice as likely to contract HIV.

Health experts stress the gel is only a prevention against HIV and herpes, not a contraceptive.