An epizootic of histoplasmosis duboisii (African histoplasmosis) in an American baboon colony.

Histoplasmosis duboisii, a chronic granulomatous disease caused by Histoplasma capsulatum var. duboisii, was diagnosed in 21 baboons at a large primate colony in San Antonio, Texas. Diagnosis was based on finding 8 to 15 microns-diameter yeast cells in histologic sections. Therapy with drugs was unsuccessful. Surgical removal of lesions was the primary treatment. Epidemiologic data suggest the incubation period to be at least 9 months. The most likely route of infection was oral and happened during grooming by the baboons.