Was the banning of DDT one of the worst decisions ever?
Actually if you look into it you’ll find that DDT is an endocrine disruptor, a possible facilitator to carcinogenesis (it has been proven to cause liver tumours in animals), in fact many studies have shown links between DDT and various forms of cancer including rectal, pancreatic and lung cancers as well as multiple myleoma. It is also one of the many pesticides which causes skin problems such as dermatitis and eczema, as can be seen on many farmers in the developing world. So, given that in general the countries where malaria is most widespread are also poorer countries that still use many pesticides and herbicides banned in the west, your point appears invalid.