Homo sapiens was born with infectious agents that circulated in the common ancestral animal from which both the man and the chimpanzee evolved. We have acquired other microorganisms while still in African territory, in the time of the hunters and gatherers. We have left Africa, have conquered the planet and have become sedentary. We discovered agriculture and animal domestication and, thus, have been invaded by new infectious agents. The microorganisms came along with human locomotion. They were present in the human migrations from Africa, in the military campaigns of Antiquity, in the ocean voyages of discovery, in the colonizations, in the slave trade and so on. The advance in the studies of microorganisms DNA and RNA clarifies the origin and the spread of various infectious diseases. We can then find out how viruses, bacteria and parasites have been globalized since our departure from Africa until the present day.
History; Epidemics; DNA; Globalization
