U.S. government officials are enthusiastically endorsing and funding the use of DDT in sub-Saharan Africa after years of resisting calls from scientists who said the insecticide would be the best weapon for fighting malaria, despite lingering objections by some environmentalists.
“We’re really pretty aggressive” about supporting DDT use against the mosquitoes that spread malaria, said Michael Miller, deputy assistant administrator of the Bureau of Global Health for the U.S. Agency for International Development (USAID).
Added Richard Green, director of the Office of Health, Infectious Diseases and Nutrition in USAID’s global health bureau: “We think DDT is an excellent insecticide and that, in some circumstances, it has some advantages over some other insecticides that are available.”
The insecticide credited with eliminating malaria in the Western world years ago was outlawed in the United States in 1972 and is banned in most countries because of environmental concerns and unsubstantiated fears it can harm humans.
“We think DDT is safe when used correctly and are not aware of any human health risks,” Mr. Green said.
USAID is the federal government’s lead agency in efforts to help African countries find ways to battle the continent’s deadliest disease, which kills about a million Africans yearly, most of them young children and pregnant women. DDT is generally cheaper and more effective than other insecticides in preventing household bites.
Later this year, Mr. Miller said, USAID will begin using DDT as part of malaria-control efforts in three nations — Mozambique, Ethiopia and Zambia. Nearly $10 million in federal funds has been allocated this year for “indoor residual spraying” in those three countries.
DDT will be one of 12 different insecticides employed in the effort, which officials hope to start in December, and it will be the one used in most of the spraying in Mozambique, Mr. Green said. Mozambique’s interest in DDT is significant, because it had long ignored pleas by its neighbor, South Africa, to use it. South Africa became a DDT booster in 2003, after using it to end a malaria epidemic in the eastern part of the country.
Of the $99 million that USAID is spending on malaria control this year, $20 million is being used for indoor spraying with DDT or one of the other 11 insecticides authorized by the World Health Organization (WHO) as malaria preventives, Mr. Green noted.
About one-third of USAID’s total budget for malaria is financing the President’s Malaria Initiative (PMI), which seeks to reduce malaria deaths by 50 percent in 15 African countries by 2010 and will spend $1.2 billion to that end. This year, PMI is doing indoor spraying in hundreds of thousands of homes in three countries — Uganda, Angola and Tanzania — using insecticides other than DDT.
“Between 1 million and 1.5 million people will be protected,” Mr. Green said.
Mr. Miller said DDT may be used in Uganda next year.
Mr. Green added that Angola’s government is considering waiving its DDT ban to allow its use in an area along its southern border with Namibia, where there are severe malaria problems. Trenton Ruebush, malaria adviser with USAID, said DDT spraying under PMI “could possibly begin this year” in that section of Angola. “Right now, they are looking at studies on the duration of effectiveness of DDT versus other insecticides.”
No one at USAID is calling for exclusive use of DDT for indoor spraying.
“WHO recommends planned rotation of insecticides to avoid” problems of mosquitoes becoming resistant to the products, Mr. Green said.