Women who have both HIV and the most common vaginal infection are more likely to transmit the AIDS- causing virus to uninfected men, a study found.
Men were three times more likely to contract HIV from their female partners if the women also had bacterial vaginosis in the three months before the men became infected, researchers led by Craig Cohen from the University of California, San Francisco, said at an AIDS meeting in Rome today.
The study is the first to show a link between HIV and an infection that strikes as many as half of all African women. While antibiotics can clear bacterial vaginosis, the disease recurs in as many as 70 percent of women within three months, Cohen said. He’s working with closely held Osel Inc., based in Mountain View, California, on a product that would replenish helpful bacteria in the vagina after antibiotics clear out the harmful ones, helping to protect against repeat infections.
“By replenishing the good guys, you’re reducing the risk of the bad guys coming back,” Cohen said in an interview today.
Cohen and colleagues recruited 2,236 HIV-negative men in seven African nations whose female partners were HIV-positive. Among those whose partners also had bacterial vaginosis, 2.9 men in every 100 caught HIV over two years, compared with 0.9 men per 100 whose partners were free of the disease. In men who acquired HIV, the researchers matched the virus genetically to their female partners to make sure they didn’t get it from someone else.
The study, funded by the Bill & Melinda Gates Foundation, was presented at the International AIDS Society’s Conference on HIV Pathogenesis, Treatment and Prevention in Rome today.
Cohen has also worked with Melbourne-based Starpharma Holdings Ltd. on an experimental gel designed to cure women of bacterial vaginosis. VivaGel, as the product is called, may be used as an alternative to antibiotics in the $350 million market for topical treatments against the infection.
In a study of 132 women who used VivaGel or a placebo every night for a week, the product cleared bacterial vaginosis in 74 percent of women within two to five days, compared with 22 percent for those using the placebo, the company said in May. It’s planning to test the gel in the third and final stage of patient studies usually needed for regulatory approval, it said at the time.
“This is powerful research that adds to my conviction that Starpharma’s VivaGel product, which is highly effective at dealing with bacterial vaginosis,” Stuart Roberts, an analyst at Bell Potter Securities Ltd. in Sydney, said in an e-mail. VivaGel “has a future role to play in limiting the spread of HIV/AIDS in both the first and emerging worlds.”