One exacting condition of the environment that we encountered was the constant exposure to disease. Dysentery epidemics were so severe and frequent that we scarcely allowed ourselves to eat any food that had not been cooked or that we had not peeled ourselves. In general, it was necessary to boil all drinking water. We dared not allow our bare feet to touch a floor of the ground for fear of jiggers which burrow into the skin of the feet. Scarcely ever when below 6,000 feet were we safe after sundown to step from behind mosquito netting or to go out without thorough protection against the malaria pests. These malaria mosquitoes which include many varieties are largely night feeders. They were thought to come out soon after sundown. We were advised that the most dangerous places for becoming infected were the public eating houses, since the mosquitoes hide under the tables and attack the diner’s ankles if they are not adequately protected. We rigidly followed the precaution of providing adequate protection against these pests. Disease-carrying ticks were so abundant in the grass and shrubbery that we had to be on guard constantly to remove them from our clothing before they buried themselves in our flesh. They were often carriers of very severe fevers. We had to be most careful not to touch the hides with which the natives protected their bodies from the cold at night and from the sun in the daytime without thorough sterilization following any contact. There was grave danger from the lice that infected the hair of the hides. We dared not enter several districts because of the dreaded tsetse fly and the sleeping sickness it carries. One wonders at the apparent health of the natives until he learns of the unique immunity they have developed and which is largely transmitted to the offspring. In several districts we were told that practically every living native had had typhus fever and was immune, though the lice from their bodies could transmit the disease.
– Isolated & Modern African Tribes, Chapter 9, “Nutrition & Physical Degenaration” by Dr. Weston A. Price