1985 Volume 47 Issue 4 Pages 617-625
During the period from July, 1981 to November, 1982, the freshwater crab, Geothelphusa dehaani, which is known as the second intermediate host of the lung fluke, Paragonimus miyazakii, was collected at 28 different localities in the central part of Wakayama Prefecture. Of the 2, 187 crabs examined, 285 (13.0%) harbored Paragonimus metacercariae. The infected crabs were found at 18 localities including seven in Ryujin-mura, six in Miyama-mura, four in Minabegawa-mura, and one in Nakatsu-mura. The infection rate of the Paragonimus metacercariae in these 18 localities varied from 2.0 to 78.9%. A total of 904 metacercariae were obtained from the 285 infected crabs. The number of metacercariae collected from a positive crab ranged from one to 26, with an average of 3.2 per positive crab. The highest incidence (78.9%) of metacercarial infection and the largest number (5.5) of the mean burden per positive crab occurred at Hachi of Miyama-mura. No Paragonimus metacercaria was observed in 1, 000 crabs collected at the remaining ten localities. On the basis of the morphological features of the metacercariae, as well as the adult flukes and the eggs recovered from the cats given the metacercariae, the flukes discovered in this investigation were all identified as P. miyazakii Kamo, Nishida, Hatsushika et Tomimura, 1961. In the present paper, the central part of Wakayama Prefecture is added as a new prevalent locality of P. miyazakii in Japan.
