Apes, lice and prehistory
Division of Infection and Immunity, University College London, 46 Cleveland Street, London W1T 4JF
Journal of Biology 2009, 8:20 doi:10.1186/jbiol114Published: 10 February 2009
Although most epidemic human infectious diseases are caused by recently introduced pathogens, cospeciation of parasite and host is commonplace for endemic infections. Occasional host infidelity, however, provides the endemic parasite with an opportunity to survive the potential extinction of its host. Such infidelity may account for the survival of certain types of human lice, and it is currently exemplified by viruses such as HIV.