Molecular characterization and histo-physiological alterations induced by concurrent helminthosis in the liver of urban commensal rodents in Punjab, India

Rodents harbour a number of parasites of public health importance, thus, they threaten human health and livestock.

The present study aimed to characterize two helminthic species found in commensal rodents and record histo-physiological alterations induced by them.

A total of 300 synanthropic rodents of three species: Rattus rattus (n=201), Bandicota bengalensis(n=90), and Mus musculus(n=09) were live trapped and necropsied in different seasons during November 2017 to October 2019 at Ludhiana, Punjab, India.

Liver of two species B. bengalensis (72.22%) and R. rattus (65.67%) were found infected with two helminthic parasites Taenia taeniaeformis, and Calodium hepaticum. These endoparasites were present either alone (4.33-6.33%) or as mixed infection (65.55%). The level of total proteins and liver marker enzymes including aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were found significantly higher in the liver of rodent species infected with single and mixed infection compared to those with no infection. In histopathological assay, granulomatous liver lesions and necrosis of hepatocytes were seen which were associated with eggs and adults of C. hepaticum and inflammatory reaction in hepatic parenchyma adjoining to cysts of T. taeniaeformis. Based upon scanning electron microscopy (SEM) identification and molecular characterization using mitochondrial cytochrome oxidase I (COI) region, the metacestodes in whitish cysts were confirmed to be of T. taeniaeformis for the first time in Punjab, India.

The study highlights an alarmingly high infection of rodents with zoonotic parasites and suggests immediate pest (rodent) control to check the dissemination of zoonotic diseases by helminth species under study.