I just did some "research" (i.e. I googled "malaria clean water") and found this:
http://eau.sagepub.com/cgi/reprint/11/1/159.pdf
and this
http://www.eyesonmalaria.org/why%20m...ling%20us.html
which both tell me that the anopheles mosquito which passes on malaria prefers clean water.
From the latter:
"The basic knowledge most Ghanaians have is that the female anopheles mosquito which causes malaria, breeds in dirty surrounding and stagnant waters. Hence, most preventive measures in Ghana are aimed at educating the populace to keep their surroundings clean and get rid of stagnant waters. But the anopheles mosquito [ . . .] which transmits malaria to humans preferred relatively clean water.
"The anopheles is choosy in terms of where it breeds," says the Manager of the National Malaria Control Programme(NMCP), Mrs. Constance Bart-Plange. She explains that the anopheles mosquito lays its eggs in areas where it can get clean stagnant water such as in flower pots, ponds, pot holes, dugout pits, hoof prints, puddles, rice fields and streams."
I have no way of telling how credible these sources are, but I expect Bill Gates can pay for proper research into the causes of malaria.
Africans need clean water. I asked my husband to pay for three Oxfam "clean water" gifts to Africa for my birthday present last year. But maybe malaria is a little more complex than that.
ETA: If you want to donate some clean water:
https://payment.csfm.com/donations/u...php?gift_id=21