DISEASE SUSCEPTIBILITY AMONG
NEW WORLD PEOPLES
Francis L. Black
New World peoples, those who were isolated from most other humans prior to the age of European exploration, had to a large extent developed a modus vivendi with parasitic microbes. A few microbes, such as the agent of tuberculosis, may have continued to cause problems (Rothschild and Hobling 2002), and some viruses that primarily infect animals, such as yellow fever (Causey et al. 1961), retained virulence for these people. However, the vast majority of infectious agents that New World people encountered in their new homes were relatively innocuous. There would have been a selection process by which agents that were preadapted and tended to cause persistent infection without debilitation would have been those carried into the new land. There may have been some selection of the host for tolerance and virus innocuity after arrival, but we are not sure how much of this reflected strains from which the agent came and how much occurred later. Strains of agents encountered in New World tend to be distinctive, such as JC, a small papillomavirus (Fernandez-Cabo et al. 2002); human T-cell lymphotropic virus type II (HTLV-II), a relative of the much-feared virus of AIDS (Biggar et al. 1998); several viruses from the herpes group (Black et al. 1974; de Freitas et al. 1994; Biggar et al. 2000); and DNA viruses. All these typically cause infection in infancy and persist throughout life.
Of particular concern here are infectious agents introduced to these people by outsiders, especially the virus measles. Like any New World