Leishmania aethiopica: infections in laboratory animals.

Leishmania aethiopica parasites were inoculated into 11 different strains and species of small laboratory animals. Clinical lesions were only produced following inoculation of hamster noses and thus this parasite is highly selective in both species and site for the laboratory animals tested. Parasites could, however, be recovered from draining lymph nodes 3 weeks after infection of BALB/c mice. Lesions in hamsters were progressive and nonulcerating (up to 1 year) and histologically resembled diffuse cutaneous leishmaniasis (DTH) in man. Pronounced delayed hypersensitivity responses to L. aethiopica antigens only developed in mice despite the absence of clinical lesions. Weak DTH responses were produced in hamsters with clinical lesions only after 25 weeks of infection.