Resistance to HIV-1 infection among highly exposed sex workers in Nairobi:what mediates protection and why does it develop?

Variability in susceptibility to infection and disease caused by infectious agents is a characteristic of all populations. Among susceptible individua ls exposed to an infection: not all become infected and among infected indi viduals, not all develop disease. It seems logical that variability in susc eptibility to infection and disease would apply to infection and disease wi th human immunodeficiency viruses. However, until recently, it has been gen erally held that there is no natural immunity to HIV-1 and that once infect ed, all individuals would ultimately succumb to AIDS. (C) 1999 Elsevier Sci ence B.V. All rights reserved.