It is impossible to claim that South Africa has been turning its back on its AIDS problem. The disease is now so endemic, and absorbs so much of the health budget at both federal and provincial levels, that it has rapidly become one of the country's top health priorities. All the more reason, therefore, to be concerned at the government's recent decision not to supply the drug AZT to pregnant women infected with HIV (see Nature 396, 504; 1998). Whatever the appeal of the argument that the money for this drug could be better used on prevention, the move threatens to undermine South Africa's credibility as an effective platform for improving the health of the whole of sub-Saharan Africa.

The statistics are horrifying enough. Nationally, officials estimate that 1,500 individuals are infected every day in South Africa, and antenatal tests have revealed that about 16 per cent of all pregnant women are HIV positive. The situation has been developing rapidly; the result, inevitably, has been an equally rapid increase in the number of children born with the infection, with the drain on both medical and social resources that this inevitably creates.

Yet Nkosazana Zuma, the country's soft-spoken but tough-minded health minister, has steadfastly refused to use government funds to pay for AZT for infected mothers. Her reasoning has a superficial logic; even though a three-month course of AZT costs only about 1,500 rand (US$250), the same money spent on prevention could — at least in theory — save many more than one (or two) lives. But this cold calculation fails to take into account a different sum: when the cost of treating a mother for this period is compared with that of providing medical treatment for an infected child — one estimate places this at more than 50,000 rand — the savings are undeniable.

Another agenda seems to be at work, one based on an implicit distrust of certain aspects of Western biomedical practice, particularly when corporate interests (as expressed through the involvement of major pharmaceutical companies) are involved. Zuma, a physician by training, has already demonstrated her disdain for some aspects of this practice through her vigorous promotion — circumventing the country's Medicines Control Council — of a group of researchers at the University of Pretoria who claimed last year to have produced a local cure for AIDS (see Nature 386, 6; 1997).

Such distrust is not totally without foundation; pharmaceutical companies are, after all, driven by private profit. And Zuma, an influential member of the ruling African National Congress, has many supporters who back the principles on which she has been standing firm (a ban on tobacco advertising has been another, equally controversial topic). The cabinet, for example, has publicly endorsed her decision not to provide pregnant women with AZT, which would have had to have been bought from Western drug companies.

But there is also a downside to Zuma's rigid stance. Some argue that it could create a situation in which drug companies will be reluctant to invest in preventative strategies if these are to be given a low priority. Others point out more concretely that children who could have been saved are being condemned to a painful, untimely and unnecessary death. The situation has already enraged some Western researchers so much that they are threatening to boycott the next (13th) international AIDS conference, due to be held in Durban in 2000. This would be a mistake; boycotts by a few individuals seldom make an effective political weapon.

But the sentiment behind the threatened boycott is correct. Whatever Zuma's suspicions of Western drugs and drug companies, withholding affordable treatment from individuals who would benefit enormously from it (a study in Thailand showed that the chance of a baby being born with HIV almost halved when the mother was given AZT) verges on the immoral. It is time for the government to rethink its stance. Little in either practical or financial terms would be lost. Much in terms of scientific and humanitarian credibility would be gained. And many lives would be saved.