Back and Forth on DDT Again

What's missing from the latest news about the World Health Organization, DDT and malaria? Context! Context! Context! Namely, if DDT had been used from the time of its invention only for public health purposes--for indoor residential spraying against mosquitoes in areas hard-hit by malaria--it would probably never have developed its toxic reputation.

The fact that agricultural interests--particularly cotton farmers--adopted wholesale DDT spraying is what killed birds and poisoned entire ecological systems.

There is a special case to be made for judicious, environmentally-protective DDT spraying of residential homes--particularly in hard-hit African countries. South Africa has shown how to do this and still protect the environment. (I wrote about this in TIME Magazine five years ago. Please also note, it was the combination of DDT and treatment with an anti-malarial drug that turned the tide.)

The World Health Organization seemed to have acknowledged that point back in 2006.

Now comes word that they hope once again to achieve a total ban on DDT, thanks to pilot programs that have used other anti-mosquito pesticides and means in Mexico and Central America. Please note: malaria is much worse, much more prevalent in central and southern Africa so what works in Mexico may have little effect in malarial zones of Africa.

As for increased resistance of mosquitoes to DDT, the point is actually not to kill the mosquitoes but to keep them from biting. And DDT is actually a better mosquito repellent than anything else--exactly what you want, according to a 2007 study in Nature Medicine.

I suppose all public health programs have an element of politics but I find it very frustrating to read news reports that pretend that all decisions with respect to DDT are made solely on a scientific basis.

Related posts:
Can Malaria Be Eradicated?
Human Health Effects of DDT