Survival of Haplorchis taichui metacercariae in Lab-Pla, Thai traditional food preparation.

Lab-Pla is a famous kind of Thai traditional food in northern and northeasthern Thailand. Consumption of uncooked Lab-Pla can lead to trematode infection because cyprinoid fish serve as the 2nd intermediate hosts of trematodes. The preparation of Lab-Pla can be made in different ways, depending on seasonings used in different places. The effect of the seasonings used in Lab-Pla on the survival of Haplorchis taichui metacercariae were, therefore, determined. The methodology was done by the following: 100 g of chopped Siamese mud carp fish (Henicorhynchus siamensis) were used for each experiment of seasonings used for completely mixed Lab-Pla. Mixed materials were blended and digested by 1% pepsin solution to obtain metacercariae and then checked for the movement under a stereomicroscope. The results showed that metacercariae remained active in 5 experimental groups: fermented fish treated, fish sauce treated, chili powder treated, ground roasted rice treated, and complete mixed treated indicated by average as follows: 27, 38.7, 33.3, 42.7 and 21%, respectively. In conclusion, fermented fish and completely mixed methods have more effectiveness in killing metacercariae in Lab-Pla preparation than other seasonings (p < 0.05).