Morphological and Morphometric Analysis of Trypanosoma lewisi and Toxoplasma gondii in Malang City, Indonesia Rats

Rats are reported to be the intermediate hosts and reservoirs of several zoonotic protozoal diseases. Trypanosoma lewisi is commonly reported in rats’ blood and is considered non-pathogenic protozoa in humans. However, some countries documented several cases in humans with T. lewisi infection. Another zoonotic protozoon that develops in rats and can be transmissible to humans is Toxoplasma gondii. We intended to present the morphology and morphometry of T. lewisi and T.gondii in wild rats collected around Malang City to explore the potential risk of transmission nearby. The rats were collected using single live traps followed by identification, sexing, age approximation, and body morphometry. All specimens were euthanized according to the standard procedure followed by blood and peritoneal fluid collection. The fluid smear preparation and Giemsa staining were performed to detect the presence of T. lewisi and T. gondii. Morphologic and morphometric analyses were conducted using ImageJ software. Among the collected 50 collected rats, 23 were identified as Rattus norvegicus (46%), 22 as Rattus rattus (44 %), and 5 as Mus musculus (1%). In the case of protozoans infection, ten individuals were infected with T. Lewisi (20%) from the blood smear check, whereas peritoneal fluid smear examination revealed an infection of T. gondii in a specimen (2%). Results of the study proved trypanosomiasis and toxoplasmosis in wild rats in Malang City. Though the clinical significance to human and public health impact is questionable, further research and surveillance of rodent-borne parasitic pathogens will provide more information for pre-emptive action