Assessment of the Role of Free-Living and Farmed Fallow Deer (Dama dama) as A Potential Source of Human Infection with Multiple-Drug-Resistant Strains of Yersinia enterocolitica and Yersinia pseudotuberculosis

Abstract

Yersinia enterocolitica and Y. pseudotuberculosis are Gram-negative, facultative anaerobic bacteria that cause yersiniosis—one of the most important zoonotic diseases of the digestive tract. The aim of this study was to determine the prevalence of potentially human-pathogenic Y. enterocolitica and Y. pseudotuberculosis strains in free-living and farmed fallow deer, and to evaluate their sensitivity to chemotherapeutics. A total of 372 rectal swabs were analyzed, including 262 from free-living and 110 from farmed fallow deer. Due to the psychrophilic properties of Yersinia, two samples were collected from each animal. Seven Y. enterocolitica strains were isolated from free-living fallow deer, while two strains were isolated from farmed fallow deer. Yersinia pseudotuberculosis strains were not identified. All isolated Y. enterocolitica strains were ystB-positive, and phylogenetic analysis based on the nucleotide sequences of this gene revealed the presence of two phylogenetic groups. Yersinia enterocolitica strains isolated from fallow deer belonged to biotype 1A, and serotyping analysis demonstrated that the vast majority did not agglutinate with any diagnostic sera. All strains were multiple drug resistant and were not sensitive to at least four of the tested chemotherapeutics (amoxicillin with clavulanic acid, ampicillin, cefalexin, and streptomycin). One Y. enterocolitica strain isolated from a free-living animal was resistant to nine out of the 13 analyzed chemotherapeutics and was intermediately sensitive to the four remaining chemotherapeutics. The highest sensitivity was noted in case of ciprofloxacin (five strains) and trimethoprim-sulfamethoxazole (three strains). Only one strain isolated from a free-living animal was sensitive to three out of the 13 examined antibiotics, whereas the remaining strains were sensitive to only one drug or were not sensitive to any of the chemotherapeutics used. The results of this study indicate that multiple drug-resistant Y. enterocolitica strains can be carried by free-living and farmed fallow deer. This observation gives serious cause for concern because the meat of fallow deer and other ruminants is often consumed semi-raw (steak) or raw (tartar steak).

Hunting Dynamics and Identification of Potentially Pathogenic Bacteria in European Fallow Deer (Dama dama) across Three Hunting Reserves in Western Romania

“…This study revealed that most of the bacteria isolated from European fallow deer can be potential health hazards to both humans and animals (e.g., Escherichia , Staphylococcus , Salmonella , Listeria , Enterococcus , Yersinia ). Moreover, the prevalence recorded in the research is in accordance with the values that were reported by other authors, which confirms that wild cervids can act as reservoirs, amplifiers, or be a link in zoonotic diseases [ 15 , 21 ]. In fact, while wildlife can pose a risk to humans and domestic animals, the majority of interactions between microbes and wildlife are innocuous and necessitate little concern [ 33 ].…”

“…Notable studies have pointed out the prevalence of pathogenic bacteria, including Escherichia coli , Salmonella spp., Staphylococcus aureus , Listeria monocytogenes , Campylobacter spp., Yersinia enterocolitica , Yersinia pseudotuberculosis or Mycobacterium bovis , within wild deer populations in Europe. This highlights the need for more comprehensive investigations to prevent the public health risks linked to zoonotic diseases or game consumption [ 15 , 18 , 19 , 20 , 21 , 22 ].…”