Genetic Identification of Echinococcus granulosus Isolates in Hamadan, Western Iran.

Background: Cystic echinococcosis is a zoonotic infection and considered as a major economic and public health concern worldwide. This research was conducted to determine genotypic characteristics of livestock and human hydatid cyst isolates from Hamadan area, western Iran.

Methods: Sampling was conducted in Hamadan industrial slaughterhouse and Beast Hospital of Hamadan City, western Iran, from 2015 to 2016. Overall, 74 livestock isolates including 69 sheep, 3 cattle and 2 goats and 9 human hydatid cysts were genotyped by PCR amplification of the rDNA ITS1 region and followed restriction fragment length polymorphism (RFLP) analysis with four restriction endonuclease enzymes, RsaI , HpaII , AluI , and TaqI , and sequencing.

Results: The PCR amplicon size of each isolate was approximately 1 kb which was the same with that of sheep strain. According to the RFLP patterns, the isolates belonged to a single species, E. granulosus sensu stricto (G1-G3 complex). Furthermore, sequencing of representative amplicons confirmed that the RFLP-genotyped isolates corresponded to E. granulosus sensu stricto.

Conclusion: E. granulosus sensu stricto is the prevailing species of E. granulosus sensu lato in the region and pointed out the importance of sheep/dog cycle in human transmission.