Infection of the Jackal (Canis aureus) by Haplorchis taichui (Trematoda: Heterophyidae) in Southwestern Iran: A Clue for Potential Human Infection

Background: We detected eight trematodes in the small intestine of a roadkilled jackal (Canis aureus) from Hamidiyeh District near the city of Ahvaz, Khuzestan Province in 2010. Methods: Three worms were stained with carmine acid, mounted in Canada balsam on glass slides and examined under a light microscope at 1000X magnification. PCR and sequencing of a partial ITS2 sequence were used to approve the diagnosis. Results: The flukes measured ≈1 mm in length with an elongated ovoid shape resembling the members of heterophyid, and only one testis, characteristics of the genus Haplorchis. Sequencing of a 481-bp fragment of the ITS2 locus from the worms revealed 97%-98% identity with the similar sequences of the H. taichui flukes previously identified in the fish, cat, and humans from Thailand, China, and Vietnam. Conclusion: Further studies with the application of reliable molecular tools to diagnose trematode infections in wildlife and humans can bring more insight into the epidemiology of fish-borne flukes including H. taichui in this area.