WHO recommends wider use of DDT to fight malaria

The controversial insecticide, DDT has been strongly recommended by the World Health Organization for killing mosquitoes that spread malaria, which has caused deaths of one million people. DDT earned an ill reputation with its widespread use outdoor which had adverse effects on the environment.

WHO says there is no health risk, and DDT should level with bed nets and other drugs as a means for struggling malaria and killing mosquitoes, which wait to bite families as they sleep.

"The scientific and programmatic evidence clearly supports this reassessment," said Dr Anarfi Asamoa-Baah, WHO assistant director-general for HIV/AIDS, TB and Malaria. "Indoor residual spraying is useful to quickly reduce the number of infections caused by malaria-carrying mosquitoes; it has proven to be just as cost effective as other malaria prevention measures, and DDT presents no health risk when used properly."

In 2004 the global treaty on Persistent Organic Pollutants (POPs) globally prohibited the use of DDT except for allowing its manufacture and use in disease control. Most of the African countries switched to other kinds of insecticides but some starting reusing DDT after mosquitoes developed resistance to the substitute compounds.

In the past, India was able to cut radically the number of malaria cases and fatalities with the use DDT in indoor residual spraying.

"We must take a position based on the science and the data," said Dr. Arata Kochi, the WHO's malaria chief. "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."

Those supporting the cause say that until better strategies are developed, carefully controlled DDT use is acceptable because in recent years, nothing else has succeeded in reducing the number of deaths from malaria.

"Indoor spraying is like providing a huge mosquito net over an entire household for around-the-clock protection," said Sen. Tom Coburn, R-Okla., a physician who has urged stronger international anti-malaria programs.

According to WHO malaria transmission can be reduced up to 90 per cent with the correct and timely use of indoor residual spraying.