How the DDT "ban" killed millions

"Now, what did the banning of DDT do to the peoples of Africa? There’s been no effective control. The world got the impression that they were spraying the jungle; this was not so.

At that time most of the use of DDT, effectively, was by spraying inside of the huts once a year or twice a year — especially the lower part — with DDT. And the insects, the mosquitoes, during the day when the sun is bright outside, they hide in darker parts. And it used to — In the case of India, when they started using DDT for malaria control, that swamp, the Torai area, was worthless. There was probably… no one knows how many millions of people with malaria. It’s not only a killer, it’s a debilitator, people can’t work effectively. It affects different people in different ways. So Ceylon, the little island, India had reduced [the number of people with malaria] from millions down to 250-300,000 people, when the ban came [on DDT]. They took it off and [the number of people with malaria] went back into the millions. In the case of Sri Lanka, they were down to 14. Took the ban off and it exploded. This is the same story, many places."

--Norman Borlaug