Hard on the heels of Earth Day came Africa Malaria Day. Earth Day got more coverage, and that's a shame, because malaria is as big a scourge as AIDS, maybe worse. Malaria kills two million people a year and ravages economies. In Africa, a child dies of malaria every 30 seconds, and many who don't die suffer brain damage. But we've been blinded by environmental paternalism. And so we're standing back and watching. The problem is our irrational aversion to DDT, which, in the popular imagination, is the most toxic pesticide known to man. So allergic are we to DDT that the World Health Organisation will not fund its use, and most agencies are pushing for a ban worldwide. This, despite massive evidence that DDT as it is used today does no harm to people or the environment - and saves lives.