Identification of trematode metacercariae species in Channa gachus in Jinghong City using PCR analysis

PCR combined with ITS sequence analysis were used to identify the type of trematode metacercariae in Channa gachus living in Jinghong City. By targeting the specific type, local health departments can prevent and control fish-borne fluke disease scientifically and reduce the risk of human infection more effectively. The Channa gachus were collected from the Jinghong city in Kunming, and metacercariaes were then extracted using artificial digestion method. DNA of different morphological cysts were extracted, PCR amplification, and sequencing analysis was conducted. Classification was performed based on morphological features of different species. Morphological identification showed that Haplorchis pumilio was found in the cheeks, fins and muscles of the snakehead, Metorchis orientalis Tanabe, Clonorchis sinensis, Centrocestus formosanus, Haplorchis pumilio and other metacercariaes. Unknown bladder worms were also present. ITS Sequence analysis results identified Haplorchis pumilio flukes. A variety of trematode metacercariaes have been detected in Channa gachus in Jinghong City. There are certain defects in the identification of trematode metacercariaes pecies only by morphological characteristics. The species can be determined by combining with ITS sequence analysis.