Almost one million dying of malaria each year, mostly in Africa, because of the horrendous consequences of the irresponsible legal or de facto ban of the use of insecticide. DDT was good enough for eradicating malaria in the Mezzogiorno and in the American South - but not in the Congo, Ethiopia, and Uganda?
That is a campaign that the Church could lead, for Africa and Africans (including many African Catholics): bring back DDT or other effective insecticides, and eradicate malaria worldwide.