LONDON, May 2 (Xinhua) -- The drug nevirapine taken by women in late pregnancy to stop their babies being infected with HIV during birth has a major downside, according to the latest issue of the New Scientist.

    Researchers at the National Institutes of Health in Frederick, Maryland, looked more carefully for specific nevirapine-resistance mutations in HIV from women given the treatment in Soweto, South Africa, and found more than a fifth had some drug-resistant HIV a year later, the magazine said, which is a challenge to the previous suggestion that any nevirapine-resistant HIV arising as aresult of the treatment disappear from the mother's body shortly after birth.

    The new study result means that if a woman takes nevirapine again, whether to treat her own disease or protect a subsequent child, it may not work. Such drug failures may already be happening in women treated years earlier, says main research SarahPalmer.

    Palmer says that ideally women should get full-time therapy with several drugs, to stop the virus becoming resistant to any one drug. Enditem