Prevalence of Haplorchis taichui Infection in Snails from MaeTaeng Basin, Chiang Mai Province, by Using Morphological and Molecular Techniques

Abstract

The investigation of biological diversity of intestinal trematode in snails which the report concerned is rarely and not extended in current status. Especially in minute intestine trematode, Haplorchis taichui Witenberg, 1930, family of Heterophyidae, which was found in the small intestine of mammals including human, and causes serious clinical problem worldwide. So, this study was aimed to investigate H. taichui infection in freshwater snails from Mae Taeng basin, Chiang Mai, Thailand. Total of 1,836 snails were collected during April 2008 to August 2012. Cercarial infection was examined by crushing method. Molecular identification of H. taichui were conducted by a DNA specific primer which amplified the mCOI gene. The PCR product of mCOI were sequenced and confirmed by BLAST program. Six types of cercariae were found viz. megalurous, furcocercous, monostome, pleurolophocercous, parapleurolophocercous, and virgulate cercaria. The parapleurolophocercous cercaria in Melanoides tuberculata, Tarebia granifera, and Thiara scabra were larval stages of H. taichui which yield the specific fragment of 256 bp. Overall of H. taichui infection of snails was 42.71%. The mCOI sequences had 99% similarity with the 29 isolated gene references of the H. taichui in Genbank data base. The molecular method had suitability as an epidemiological tool for suitable control programs against the dissemination of trematodes.