Canine histoplasmosis in Rio de Janeiro: natural and experimental infections.

Seven of 73 mongrel dogs in Rio de Janeiro gave positive results in skin tests with a polysaccharide mycelial antigen from Histoplasma capsulatum. Five of the positive reactors were necropsied and four of them had disseminated histoplasmosis proved by histopathology and culture. Four healthy puppies exposed for 10 min to soil at the site of a known outbreak of histoplasmosis developed symptoms and died 7-14 days after exposure with fulminant histoplasmosis. These experiments show the value of dogs as epidemiological indicator of histoplasmosis and as experimental models for the disease.