Attempts to establish infections with Strongyloides stercoralis in mice and other laboratory animals.

Infection of a dog with Strongyloides stercoralis filariform larvae resulted in a persistent infection. Patent infections were not seen in rabbits, guinea-pigs, rats and 11 inbred strains and one outbred strain of mice. Manipulation of factors known to influence S. ratti infections in mice, such as age and sex of the host and the route of larval presentation, did not facilitate the appearance of rhabditiform larvae in the stools. Administration of immunosuppressive doses of corticosterioids to rabbits, guniea-pigs and C57Bl/6 mice did not permit complete development. Similarly, th course of infection was not altered in T cell-deficient hypothymic (nu/nu) mice. The fate of filariform larvae applied to the skin of mice was ascertained; filariform larvae were observed to migrate from the skin via the lungs to the muscles within several days of infection. Although S. Stercoralis does not develop to maturity in the small intestine of mice, this system does allow in vivo studies of the actions of anthelmintics against filariform larvae as well as a number of aspects of the immune response to this parasite.