Protection of mice against intestinal amoebiasis with BCG, Corynebacterium parvum and Listeria monocytogenes.

Treatment with Corynebacterium parvum or BCG, or infection with live Listeria monocytogenes was found to protect mice against subsequent infection with Entamoeba histolytica. Complete protection was obtained in mice treated with 10(7) (colony forming units) of BCG but not with 10(5). Partial protection was achieved with 10(6) of BCG. These data provide evidence that non-specific immunity plays an important role in the host defense against amoebic infection.