Schistosoma mansoni

Prepared by: Michael J. Huerkamp, DVM, Diplomate ACLAM

Date: October 29, 2001

Agent: Schistosoma mansoni

Schistosomes are trematode (fluke) parasites found in tropical areas of the world. They infected the bloodstream and certain tissues of mammals. Contact with infected aquatic snails or water containing infectious forms of the parasite and shed from infected snails is required for transmission of the parasite to humans. Experimentally schistosome infection is used to study the effects of parasitism on immunology and for drug treatment research.

Potential Hazard: Laboratory-associated infections with schistosomes acquired from mammals are unlikely and have never been reported. Depending upon the species of parasite and the species of the host it is possible for eggs to be shed in the urine and feces of an infect animal. These eggs, however, are not infectious for humans, because infection of a snail is required to complete the life cycle.

Recommended Precautions: The animal biosafety level II practices (DAR SOP 400-3) will protect husbandry personnel against exposure or infection. Safe and effective drugs are available for use in humans.

References: Biosafety in Microbiological and Biomedical Laboratories, 4th edition, CDC-NIH, 1999, pp. 129-30