HIV: An Evolutionary Perspective

Abstract HIV: An Evolutionary Perspective Arthur J. Stepp; April 2001 Human Immuno-deficiency Virus (HIV) poses a significant threat to global health. Despite the fact that the number of cases of HIV is growing exponentially, there is no known cure for the disease and little understanding of its mechanism of pathogenesis. An application of an evolutionary perspective understanding may provide new insight into how natural selection acts upon HIV to increase its level of virulence, and also HIV's pathogenesis. By applying the replication rate hypothesis theory developed by Paul Eward in 1994 to epidemiological evidence from Africa, it becomes clear that as the replication rate of the virus increases, the mutation rate increases simultaneously. People who have been infected for the longest amounts of time tend to have more virulent, powerful strains of HIV as the virus has gone through more replications and has thus developed more powerful mutations that tend to advance to AIDS more quickly. This has important implications for the best approach to combatting the spread of the virus, because it means that preventing unprotected contact with people with highly mutated strains of the virus will greatly reduce the virus's virulence. Thus, the reduction of unprotected sexual contact and needle-borne transmission will pay extra dividends, as highly virulent strains of HIV will be better contained.