Paragonimus Metacercaria Prevalence in Freshwater Crabs in the Markets in Bang Phli district, Samut Prakan Province, Thailand - ความชุกของพยาธิใบไม้ปอดระยะติดต่อ (metacercaria) ในปูนา ในตลาดสด เขตอำเภอบางพลี จังหวัดสมุทรปราการ

Abstract

                 Fresh water crabs are the second intermediate host of Paragonimus metacercaria. The objective of this cross-sectional survey was to study the prevalence of Paragonimus metacercaria in 100 crabs in the markets at Bang Phli district, Samut Prakan province, Thailand. Ninety-one percent of Paragonimus metacercaria were found in the samples. Proportion of metacercaria found in male and female crabs were 94.2 percent of the 35 male crabs and 89.2 percent of the 65 female crabs. On average, a male crab contained 35 metacercaria in an infective stage while a female crab harboured 23. The number of metacercaria found in male and female crabs were significantly different (p<0.05) by chi-square test. The simple sedimentation method (after grinding by blender) was used for detection of metacercaria in fresh water crabs. Based on the morphology classification of metacercaria, only Paragonimus siamensis was found in this study which might be the cause of ectopic paragonimiasis in human. Therefore the researchers believe that the prevalence of metacercaria in fresh water crabs should lead to a study on infective stage Paragonimus metacercaria epidemiology, by using polymerase chain reaction to confirm the genus and species.
Key words: genus Paragonimus, metacercaria, fresh water crabs, simple sedimentation method