Identification and investigation of Calodium hepaticum in rodents and insectivores from Wuhan section of the Yangtze River in China

ABSTRACT

Objective: To investigate the prevalence of Calodium hepaticum (C. hepaticum) in rodents and insectivores from Wuhan section of the Yangtze River in China, and to provide evidence for the prevention and treatment of hepatic Calodium infection.Methods: Rodents and insectivores were captured from three selected Yangtze River beaches using mousetraps. The three survey sites were divided into six areas according to natural conditions, with 60 mousetraps placed in each area. The liver lesions in the captured rodents were observed by the naked eye and the eggs in the liver tissue were observed by microscopic examination. Results: A total of 1080 mousetraps were placed, and 1075 mousetraps were retrieved, with the retrieve rate as 99.5％. A total of 101 Apodemus agrarius, 12 Rattus norvegicus, and 9 Crocidura attenuata were caught. The average density of rodents and insectivores was 10.5％ and 0.8％, respectively. DNA of egg nodules from infected rodents showed 98％ similarity with that of C. hepaticum 18S rRNA (LC425008.1). One Rattus norvegicus was infected with C. hepaticum, with an infection rate of 3.23％ in the Erqi river beach; the other two beaches did not show the incidence of C. hepaticum. Conclusions: The monitoring of C. hepaticum in the Yangtze River beaches should be strengthened to reduce the risk of human C. hepaticum infection.