Thirty years after phasing out the use of indoor residual house spraying with DDT to control malaria infections, the World Health Organization (WHO) has announced that it will re-integrate this life-saving intervention into its malaria control programs.
DDT was considered a miracle pesticide after widespread use of it in the 1940s and 1950s led to the eradication of malaria in many areas of the world. Greece saw malaria cases drop from 1-2 million a year to nearly zero after a massive DDT spraying campaign. So why was this miracle intervention banned? Fears of DDT and other chemical pesticides can be attributed to the rise of the environmental movement and Rachel Carson's book _Silent Spring_, which claimed that DDT could be a threat to wildlife. These claims are dubious, and no scientific study has been able to link DDT to any adverse human health effects even among the pesticide-soaked workers of anti-malarial programs and the prisoners who ate DDT in volunteer experiments.
Last year, the Lancet published a report weighing the benefits and risks of DDT use. It covered all the usual suspected illnesses associated with exposure to chemical pesticides, including cancer. For all diseases or dysfunctions, there was either no, or at most a very weak, association with DDT.
Finally, the WHO has taken a position on DDT based on scientific evidence and not unfounded fears. "We must take a position based on the science and the data," said Dr. Arata Kochi, Director of WHO's Global Malaria Program. "One of the best tools we have against malaria is indoor residual house spraying. Of the dozen insecticides WHO has approved as safe for house spraying, the most effective is DDT."
Why do environmental activists continue to stoke fears concerning DDT use? In today's Wall Street Journal ("WHO Calls for Spraying Controversial DDT to Fight Malaria"), Jay Feldman — executive director of Beyond Pesticides, a Washington-based organization that advocates the elimination of pesticide use — says wider use of DDT is "shortsighted and doesn't recognize the long-term problems and hazards." One million dead African children each and every year isn't a problem? Massive economic disruption in Africa due to illness isn't a hazard? Banning DDT use was a public health disaster, and hopefully with the WHO's new position, Africa and other malaria-endemic regions of the world will see drastic reductions in malaria deaths.