LONDON -- Half of all teenage boys in South Africa will eventually die of AIDS, predicted a United Nations report last year. "The world has never before experienced death rates of this magnitude across young adults of both sexes across all social strata," it added -- and noted that 70 percent of all the world's HIV-positive people are Africans, although Africans are only 10 percent of the human race.

Drugs exist that could prolong the lives of many of those Africans indefinitely. True, the triple AIDS therapy now on offer in the United States costs about $10,000 per patient per year -- but an American "generic" manufacturer, asked to calculate the price of the same therapy if he didn't have to respect patent rights, came up with the figure of $230 a year. Move the manufacturing to Brazil or India or South Africa, and you would bring the price down further.

Why, then, haven't the drug companies who hold the patents said, "Go ahead and do it. We'll make our profit in those parts of the world where people can afford to pay large amounts of money for our drugs. Africa is facing an immense continent-wide humanitarian emergency -- and Africans can't pay enough to make them an interesting market for us anyway, so we're not losing anything. Do it, and save some lives."