Cycle of parasite transfer: Oriental lung fluke Paragonimus westermanii

This parasite is readily transfered from host to host through consumption of raw or undercooked flesh of an infected host organism. In humans and other mammals this parasite can cause sometimes-fatal, tubercular-like symptoms. P. westermanii was epidemic in post-war Japan. Although advances in diagnosis and education as to the route of exposure contributed to the decline of the parasite, the increasing demand for raw freshwater crab is predicted to be accompanied by a rise in P. westermanii infections. (Gyoten, J. 1994. Changes of living habits related to the infection in human paragonimiasis in Japan. JAP. J. PARASITOL. 43(6)462-470)

Parasitologists studying Chinese mitten crabs in San Francisco Bay have found no evidence of P. westermanii although suitable freshwater snail hosts do exist in the waters of California and adjacent states. (Cohen and Carlton, 1995)

 

created 5/4/98