Fever of unknown origin due to zoonoses.

Fevers of unknown origin have been classified as classic, nosocomial, immune-deficient, and HIV-related. More than half of the 1407 human pathogens are zoonotic, making zoonotic infections an important subcategory in each of the classifications. This article describes both common and unusual zoonoses causing fevers of unknown origin. Simian immune virus is considered as a possible emerging infection. For special populations (the homeless, zoophiliacs, those whose occupation or leisure brings them in close contact with oceans or lakes, and veterinarians), zoonotic infection potentials are discussed.