Occurrence and Genetic Correlations of Yersinia spp. Isolated from Commensal Rodents in Northeastern Poland

Abstract

Rodents can be a potential Yersinia spp. vector responsible for farm facilities contamination. The aim of the study was to determine the prevalence of Yersinia spp. in commensal rodents found in the farms and fodder factory areas to characterize the obtained isolates and epidemiological risk. Intestinal samples were subjected to bacteriological, bioserotype, and PCR examination for virulence markers ail, ystA, ystB, and inv presence. Yersinia spp. was isolated from 43 out of 244 (17.6%) rodents (Apodemus agrarius n = 132, Mus musculus n = 102, Apodemus sylvaticus n = 8, Rattus norvegicus n = 2). Y. enterocolitica was isolated from 41 rodents (16.8%), and from one Y. pseudotuberculosis and one Y. kristensenii. In three cases, two Y. enterocolitica isolates were obtained from one rodent. All Y. enetrocolitica contained ystB and belonged to biotype 1A, considered as potentially pathogenic. One isolate additionally had the ail gene typical for pathogenic strains. The sequence analysis of the ystB, ail, and inv fragments showed a high similarity to those from clinical cases. The current study revealed a high prevalence of Y. enetrocolitica among commensal rodents, but the classification of all of Y. enterocolitica isolates into biotype 1A and the sporadic isolation of Y. pseudotuberculosis do not indicate a high epidemiological risk.

Virulence Determinants and Genetic Diversity of Yersinia Species Isolated from Retail Meat

“…The presence of virulence genes of clinical importance (ail, myfA and ystA) was identified previously in non-pathogenic Y. enterocolitica and other Yersinia-Y. kristensenii and Y. intermedia [9,39,46].…”

“…Despite lacking classical virulence markers, with the exception of ystA in Y. kristensenii, in the present study, other pathogenicity factors may contribute to Yersinia virulence. ystB of Y. enterocolitica 1A was considered as potentially pathogenic, and high similarity between clinical and rodent isolates of ystB, ail and inv fragments was shown [46]. The presence of virulence genes of clinical importance (ail, myfA and ystA) was identified previously in non-pathogenic Y. enterocolitica and other Yersinia-Y.…”

“…The ail gene is widely targeted to confirm Y. enterocolitica pathogenicity [23]. Previous reports show the sporadic presence of the ail gene in Y. enterocolitica 1A and other Yersinia species in clinical, animal and food samples, raising debates regarding its significance in epidemiology of human yersiniosis [13,23,26,46].…”

Yersinia enterocolitica in wild and peridomestic rodents within Great Britain, a prevalence study

“…(2020) discovered five Y. enterocolitica isolates that despite being classified as biotype 1A also harboured the y stB as well as ail gene , an important marker of pathogenicity. Although, virulence genes are known to be present in biotype 1A such as yst (Thoerner et al., 2003) and ail (Sihvonen et al., 2011), these are rare findings, and as such the results of this study, similar to those of Platt‐Samoraj et al., (2021), are unexpected and require further investigation and research to explore alternative explanations for these findings. Nevertheless, Thoerner et al.…”

“…Nevertheless, Thoerner et al. (2003) describe how it is not possible to distinguish between pathogenic and apathogenic isolates within this biotype based on the virulence gene detection alone, and instead requires biotyping to truly identify a pathogenic strain, a sentiment which is reinforced by this study's and multiple other studies' results (Platt‐Samoraj et al., 2021; Sihvonen et al., 2011).…”