Grassland versus forest dwelling rodents as indicators of environmental contamination with the zoonotic nematode Toxocara spp.

Abstract

Small mammals are suspected of contributing to the dissemination of Toxocara canis and helping with the parasite survival during periods when there is a temporary absence of suitable definitive hosts. While the primary aim of the current study was the assessment of seroprevalence of Toxocara spp. infections in wild rodents in Poland, we also explored the role of intrinsic (sex, age) and extrinsic factors (study site) influencing dynamics of this infection to ascertain whether grassland versus forest rodents play a greater role as indicators of environmental contamination with T. canis. We trapped 577 rodents belonging to four species (Myodes glareolus, Microtus arvalis, Microtus agrestis, Alexandromys oeconomus) in north-eastern Poland. Blood was collected during the parasitological examination, and serum was frozen at − 80 °C until further analyses. A bespoke enzyme-linked immunosorbent assay was used to detect antibodies against Toxocara spp. We found Toxocara spp. antibodies in the sera of all four rodent species with an overall seroprevalence of 2.8% [1.9–4.1%]. There was a significant difference in seroprevalence between vole species, with the grassland species (M. arvalis, M. agrestis and A. oeconomus) showing a 16-fold higher seroprevalence (15.7% [8.7–25.9%]) than the forest-dwelling M. glareolus (0.98% [0.5–1.8%]). We hypothesise that the seroprevalence of Toxocara spp. differs between forest and grassland rodents because of the higher contamination of grasslands by domestic dogs and wild canids. Our results underline the need for wide biomonitoring of both types of ecosystems to assess the role of rodents as indicators of environmental contamination with zoonotic pathogens.

Comprehensive control of toxocariasis in communities

“…Viable larvae have been found even after 9 years of residence in non-human primate tissues [38]. This information can be extrapolated to the role that small mammals play in maintaining L3 in hypobiosis in their tissues, which when preyed on by dogs or cats would help maintain the parasite cycle within urban communities [39]. For these reasons, cats are underestimated in Comprehensive Control of Toxocariasis in Communities DOI: http://dx.doi.org/10.5772/intechopen.1005054 their role in human toxocariasis, even though their offspring can become infected transmammarily, thus allowing superinfected kittens [40].…”

A walk on the wild side: A review of the epidemiology of Toxocara canis and Toxocara cati in wild hosts

“…In N.E. Poland, Krupińska et al (2023) investigated four rodent species from both grassland and forest habitats. They reported a 16-fold higher seroprevalence among grassland inhabiting species ( Microtus arvalis, Microtus agrestis , Alexandromys oeconomus ) (15.7%) in contrast to the forest dwelling Myodes glareolus (0.98%).…”

Identification of <i>Toxoplasma gondii</i> in wild rodents in Poland by molecular and serological techniques

“…Felid species, including domestic cats and their relatives, are the definitive hosts and the only hosts that can shed oocysts into the environment [5]. Environmental contamination is an important health issue, therefore monitoring of the occurrence of this parasite is crucial for the One Health approach [6,7]. Rodents pose a particular threat to public health because they are intermediate hosts of T. gondii and are also the reservoirs of infection for other animals [8].…”