LONDON, Feb. 22 (Xinhua) -- A study carried out by British researchers has revealed that a drug designed to combat genital herpes can reduce levels of HIV in the blood by 70 percent and also appears to reduce levels of HIV in the genital tract.

    Researchers of the London School of Hygiene and Tropical Medicine, UK, had the findings after having carried out a small trial in Africa, New Scientist reported Thursday on its website.

    The researchers led by Philippe Mayaud recruited 140 women infected with both HIV and herpes in the West African nation of Burkina Faso and gave half of the women valacyclovir and the other half women placebo pills for three months.

    The researchers found that copies of HIV in those who received valacyclovir had dropped from 25,000 copies per milliliter of blood to 8,000 per milliliter - a 70 percent reduction and levels of HIV found in the blood of women who received the placebo, by comparison, had increased slightly on average.

    The women who received valacyclovir also had half as many copies of HIV in their genital tracts compared to those who received the placebo, suggesting that valacyclovir has the potential to reduce the spread of HIV, Mayaud said.

    This is the same effect one would expect if the women had been given an anti-HIV drug such as Zidovudine (AZT), according to Mayaud.

    The herpes medication, valacyclovir, and other herpes drugs, might dramatically reduce the spread of HIV, according to the researchers.

    Researchers believe that valacyclovir indirectly reduces HIV infection by decreasing copies of the herpes virus and note that untreated herpes can cause lesions in the genital region, which subsequently attract a type of immune cell that harbors HIV.

    Mayaud stressed the need for long-term studies of valacyclovir's effect on HIV infection.