DDT was NEVER banned for public health purposes in Africa or anywhere in the Developing World.
It was restricted for use in agriculture to ensure --in part-- that it continued to be useful for public health. As far back as the late 1950s it was known that mosquitos easily developed resistance to DDT and other insecticides.
I suppose I can farm some of my own links, but if you have more please LMK!
https://www.scientificamerican.com/article/ddt-use-to-combat... (Article mentions that we are still using DDT in africa)
https://www.sciencedaily.com/releases/2014/02/140224204808.h... (a single mutation is required to for mosquitos to become DDT resistant)
Think about this: At least in the western world we have achieved wealth and productivity where the word "unimaginable" from a point of view of even 500 years ago would be a gross understatement. And yet, to many people daily life still feels full of threats, while many work what they themselves recognize are meaningless jobs (see the popular Dilbert cartoons). It doesn't make sense, it is artificial. It doesn't need to be this way. We force people - and organizations - to live in a "stress and survival mode" that is completely unnecessary.