Today's WSJ reports (link for subscribers):
The World Health Organization, in a sign that widely used methods of fighting malaria have failed to bring the catastrophic disease under control, plans to announce today that it will encourage the use of DDT, even though the pesticide is banned or tightly restricted in much of the world.
The new guidelines from the United Nations public-health agency support the spraying of small amounts of DDT, or dichloro-diphenyl-trichloroethane, on walls and other surfaces inside homes in areas at highest risk of malaria. The mosquito-borne disease infects as many as 500 million people a year and kills about a million. Most victims are in sub-Saharan Africa and under the age of 5. . . . .
DDT already is on a list of WHO-approved chemicals for indoor spraying. But until now, the agency hadn't strongly endorsed its use, and donors funding malaria programs were reluctant to finance purchases of it. As a result, countries hit hardest by malaria generally have been unable to afford substantial supplies. The WHO's new stance is aimed partly at encouraging even countries that ban the pesticide to help finance its use in areas ravaged by the disease. . . .
Other pesticides and malaria-fighting methods have often proved to be less-effective and more costly than DDT. Insecticide-treated mosquito nets hung in sleeping areas are successful, but cost, distribution problems and varying usage make them less effective than they could be. Malaria experts say deployment of a malaria vaccine that is now in development could still be years away.
Pressure has been growing in the past few years for the WHO to support DDT more aggressively. Jon Liden, a spokesman for the Global Fund, which pays for indoor spraying of DDT or other pesticides in 41 countries, says the organization welcomes the WHO's move. "The Global Fund....is ready to finance increased use of the strategy if affected countries request it," he says.
The U.S. government has stepped up support for indoor pesticide spraying of homes in Africa. While it spent less than $1 million on such programs in 2005, it plans to spend $20 million in fiscal 2007, according to Admiral R. Timothy Ziemer, coordinator of the President's Malaria Initiative and the U.S. Agency for International Development's malaria programs. This year, the U.S. government purchased DDT for a spraying program in Zambia.
This seems like a very positive development. While excessive DDT use in the United States was linked to reproductive problems in several bird species, respnsible indoor spraying of DDT is an important, cost-effective component to a comprehensive malaria-control strategy in developing nations.