Commensal Brown Rat (Rattus norvegicus) as a carrier of potential zoonotic parasites in the urban area of Bosnia and Herzegovina
Commensal rats are highly adaptable to coexisting with human populations, often relying on human dwellings and immediate access to food, water, shelter and space. We present the case of an adult commensal brown rat, Rattus norvegicus, that was found in an urban area of Sarajevo (Bosnia and Herzegovina). Histopathological examination revealed numerous eggs of Calodium hepaticum in the liver parenchyma and coprological examination identified species of the class Cestoda (Rodentolepis spp., Hymenolepis diminuta) and the class Nematoda (Trichuris muris, Nippostrongylus brasiliensis and Strongyloides ratti). Haematological parameter analysis was conducted using the “Idexx ProCyte Dx” cell counter and biochemical parameters of the rat's serum were tested. Haematocrit, haemoglobin content and erythrocyte indices (MCV, MCH) were decreased and moderate quantities of spherocytes were present (4.95 %). The total number of leukocytes was within the physiological range, with minimally increased values of monocytes and neutrophils and decreased values of eosinophils. The results of the morphometric examinations were in the expected range for adult rats. This case report highlights the public health risk posed by commensal rats if systematic rodent control measures are not fully implemented. It should serve as a guide for future research on the population of commensal rats in the cities of Bosnia and Herzegovina, aimed at a detailed identification of parasitic zoonotic pathogens.