Abstract: Objective  To investigate the second intermediate host of Paragonimus and its cysticercosis infection in some areas of Minjiang River Basin, so as to provide evidence for the control of Paragonimus in the basin. Methods  Investigation on the second intermediate host of Paragonimus and its cysticercosis infection was carried out in the villages in the upper reaches, around the upper reaches and some areas in the middle of Minjiang River. The stream crabs captured were identified, from which the metacercariae were collected using double screen method, and microscopically examined to calculate the infection rate, infection degree and infection index of crab. Results  595 stream crabs were captured. The total infection rate of metacercariae was 36.81%, and the infection rate was 54.93% (78/142), 44.03% (59/134) and 25.71% (82/319) in the villages in the upper reaches, around the upper reaches and some areas in the middle of Minjiang River. The difference was significant in the three areas (χ²=39.96, P<0.05). The overall infection index was 5.90, and the infection rate of metacercariae was 13.47, 7.80 and 2.17, respectively for the three areas where were foci of high risks. Eight species of stream crabs were caught, in which 7 species were infected except Huananpotamon sheni. The infection rate was the highest in Sinopotamon jianglense (65.25%, 77/118) and B. youxiense (64.58%, 31/48). The difference was significant among the crab species (χ²=95.86, P<0.05). Three species of metacercaria of Paragonimus (Paragonimus westermani, P. skrjabini and Euparagonimus cenocopiosus) were microscopically identified. Conclusion  The infection rate of Paragonimus appears relatively higher in some areas of Minjiang River basin, which should call our attention, and effective measures be taken to prevent and control the infection in population. 

Key words: Paragonimus, Metacercariae, Stream crab, Minjiang River, Fujian Province