Title : Assessment of the role of free-living forest mammals as a potential source of Yersinia enterocolitica infection
Abstract:
Free-living animals are an important environmental reservoir of the pathogens dangerous for other animal species and humans. One of those is Yersinia (Y.) enterocolitica, the causative agent of yersiniosis – foodborne, enzootic disease, significant for public health. Y. enterocolitica has been divided into six biotypes based on its specific biochemical features (1A, 1B, and 2 – 5), and more than 70 serological groups have been identified based on chemical variations in the thermostable somatic antigen O. The objective of this study was to identify the bioserotypes and virulence markers of Y. enterocolitica strains isolated from different species of free-living forest mammals: red foxes (Vulpes vulpes), European hares (Lepus europaeus), European hedgehogs (Erinaceus europaeus), European beavers (Castor fiber) and European rabbits (Oryctolagus cuniculus). Sixteen Y. enterocolitica strains have been found in samples obtained from red foxes, while the pathogen has not been isolated from other species. Eight strains were isolated from warm enrichment (ITC), and eight from cold enrichment (PSB). 1A/NT (not-typable) was the most common Y. enterocolitica bioserotype. It was detected in 6/16 (37.5%) isolates. The remaining strains were represented by bioserotypes: 1A/O:8 – 3/16 (18.75%), 1B/NT – 2/16 (12.5%); 2/NT – 2/16 (12.5%); 1A/O:3 – 1/16 (6.25%); 1A/O:5 – 1/16 (6.25%) and 3/O:3 – 1/16 (6.25%). Presence of amplicons corresponding only to ystB gene fragments was demonstrated in 12 of examined Y. enterocolitica strains. Amplicons corresponding to ail and ystB genes were noted in 3 Y. enterocolitica biotype 1A strains and one Y. enterocolitica biotype 3 strain. Ail-positive strains belonging to biotype 1A are extremely rare. Research has shown that red foxes may be the carriers, shedders and potential source of Y. enterocolitica infections for other animal species and indirectly for humans. Funded by the Minister of Science under the “Regional Initiative of Excellence Program”