Canine Paragonimiases in Ehime Prefecture, Japan

Abstract

Four cases of canine paragonimiasis, accompanied by a main symptom of bad cough, were detected in Kami-ukena-gun, Ehime Prefecture in 1975-1978. Eggs excreted into the feces were ovoidal or elliptical in shape and measured approximately 75μm in length and 45μm in width. The maximum width was measured at the middle portion in many of the eggs. The operculum was approximately 4μm long and 20μm wide. The egg shell measured about 1μm in thickness and no thickening or processes were present in the shell on the opposite side of the operculum. The eggs were identified by their morphological features as those of Paragonimus miyazakii and it was considered that P. miyazakii infection of dogs was prevalent in this area. By oral administration of bithionol in a dose of 50mg/kg once or 25mg/kg twice a day for 5 consecutive days, the clinical signs and the excretion of eggs into the feces disappeared in all four cases. The autopsy of one of the four dogs, six years after chemotherapy, revealed no gross lesions in the lungs.