I think that DDT holds a lot of promise. It hasn't been banned everywhere - obviously it has in the U.S. In fact, about 10 years ago, the WHO came out with a statement promoting it for public health interventions in many countries. It's cheap. It's very, very effective. We've never had an insecticide that has worked so well since. It's also safe. A lot of people don't realize that its toxicity profile for humans is low.