Health campaigners have accused the pharmaceutical industry of trying to sabotage attempts by developing countries to relax patent rules in the World Trade Organisation by using new research to demonstrate that patents are not blocking access to cheap Aids and other drugs in Africa.

A paper published today in the Journal of the American Medical Association argues that "patents in Africa have generally not been a factor in . . . anti-retroviral drug treatment access".

Similar research carried out by PhRMA, the US pharmaceutical industry association, shows that in Africa, of the 16 anti-retroviral drugs used for treating Aids, patent coverage is below 20 per cent, with fewer than 150 patents out of the 832 that could theoretically apply.

Of 52 African nations, only South Africa has patent protection more or less across the board, with 15 patents out of a possible 16. Twenty-one have no patents and the rest have eight or fewer, with no patents on more than a dozen different triple-therapy cocktails for Aids sufferers.

"For these drugs, Africa is a patent desert," PhRMA says. "Patents are simply not an obstacle to access in almost every sub-Saharan African nation." Industry representatives also point to discounted prices for patented drugs under United Nations-sponsored programmes for poor African nations and donations of drugs such as nevirapine, which is used to prevent mother-to-baby transmission of the Aids virus.

The pharmaceutical industry argues poverty and lack of infrastructure are more important barriers to access in countries that spend as little as Dollars 10 per person per year on health, putting even the cheapest generic triple cocktail offer by India's Cipla - Dollars 350 (Pounds 238) per person per year - out of reach.

However, five health campaign groups, including Oxfam and Medecins Sans Frontie`res, say in a statement today that the same data reveal extensive patent protection of the most practical and sought-after drug combinations to treat Aids.

Patents on the full range of anti-retroviral drugs in South Africa also block access by generic competitors to sub-Saharan Africa's biggest market with the associated economies of scale. Even so, patented prices are still three times higher than generic prices, they say.

The US and some other countries are resisting pressure from developing countries led by Brazil and India, both important generic manufacturers, to increase the leeway under WTO rules for compulsory licensing of pharmaceuticals.

* Between 7m and 10m South Africans would have died of HIV/Aids by 2010 if the disease was left untreated by the state, the South African Medical Research Council (MRC) said yesterday, James Lamont writes in Johannesburg. In a report, the MRC said that 40 per cent of deaths of people between the ages of 15 and 49 last year were as a result of HIV/Aids infection. About 20 per cent of all adult deaths were attributable to the disease. "Do patents for anti-retroviral drugs constrain access to Aids treatment in Africa?"; Amir Attaran and Lee Gillespie-White; www.jama.ama-assn.org