The majority of people with HIV infection also have herpes simplex virus-2 infection. Multiple studies have shown that frequent genital herpes recurrences increase the amount of HIV in the blood and genital tract.
The HIV virus is also shed from genital herpes ulcers and individuals with such ulcers transmit HIV to others more efficiently, the researchers said.
Researchers at the University of Washington in Seattle conducted studies among 3,408 African HIV discordant couples, in which one partner had HIV and the other did not.
In all the couples, the partner who had HIV also had herpes simplex virus-2 infection. The study took place at 14 sites in seven countries in eastern and southern Africa -- Botswana, Kenya, Rwanda, South Africa, Tanzania, Uganda and Zambia.
In the primary analysis of HIV transmissions determined by laboratory testing to have occurred within the couple and not acquired from an outside partner, there were 41 infections in the acyclovir arm and 43 in the placebo arm -- not a significant difference, researchers said.
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