five and six hundred years ago, it was the threat of malaria that held off european explorers from penetrating deeper into the hinterlands of africa. unlike their successes in the americas, where the diseases they introduced devestated the indigenous peoples, africa had waiting a number
of scourges which europeans had not developed any natural defenses against. malaria, yellow
fever, some pestilence passed on by the tse-tse fly (possibly a different strain of yellow fever) and a host of other diseases. africa could be as anglicized today as south america is
if not for those alien viruses the europeans could not defend against.