For years they've used Doxycycline Hyclate to prevent malaria.
Doxycycline is a close relative to HCQ. Because of this, many Africans have an already built in immunity to Covid.
They are completely unrelated to each other.
No, doxy is a later generation tetracycline, not at all related to HCQ. I ate it nearly every day for malaria prevention when I lived in an area where resistant malaria was rife. It works pretty well, so long as you don’t get eaten alive by mozzies positively loaded with the stinking parasites (as I was one time).