HIV infection is not so easily spread by heterosexual sex as scientists had feared.
French doctors made the discovery after working with couples wanting a baby where the man was HIV positive. They say that HIV infection of the woman is infrequent during natural conception.
Of the 92 couples they were counselling, no women became infected during the first three months after conception, although two were HIV positive by the seventh month of the pregnancy, and two more became infected after the birth.
L Mandelbrot and his colleagues from the obstetrical unit at the Cochin Port Royal hospital in Paris say their findings are in line with infection rates of 1 per 1000 acts of unprotected sex among stable heterosexual couples (The Lancet, 1997; 349: 851-2).
The natural levels of the antioxidant glutathione (GSH) could determine the length of time someone survives with HIV. Leonore Herzenberg, a professor of genetics at Stanford University, claims that HIV infected patients with fewer than 200 CD4 cells but with normal GSH levels had a 20 per cent risk of dying within three years, but the risk rose to 80 per cent among those with a similar CD4 count but with low GSH levels.
Herzenberg says the drug acetylcysteine can replenish GSH levels, and sufferers should be advised to avoid GSH depleting substances such as alcohol, paracetamol and UV radiation.