Experimental studies of microbial populations and incidence of zoonotic pathogens in the faeces of red deer (Cervus elaphus).

Abstract

Wild animals can serve as hosts, amplifiers or reservoirs for various zoonotic diseases. Most species of deer in highly fragmented agricultural landscapes, search out maximum cover from intrusive human activity. Hence, the likelihood of zoonosis transmission is likely to increase the more humans and wildlife interact. In our study, we conducted a comparative analysis of bacteria isolated from the faeces of red deer (Cervus elaphus) living in their natural environment in south-western Poland and brought in from Hungary and Slovakia under a species reintroduction programme. The faecal bacterial flora from 120 specimens of deer were examined, with particular attention to potentially pathogenic agents. We isolated 458 micro-organisms, of which 13 (2·84%) were identified as EHEC (Enterohaemorrhagic Escherichia coli) strains, and of these one strain, produced the Shiga toxin. No strain was identified as having ESBL (Extended-Spectrum Beta-Lactamase) resistance. Other bacteria that are important in terms of the health of humans and animals included Yersinia enterocolitica (4, 0·67%) and Staphylococcus aureus (4, 0·67%), but without methicillin resistance, and Listeria monocytogenes (8, 1·75%). Of all the micro-organisms 138 (30·13%) were bacteria of the genus Enterococcus, including 12 (2·62%) of the species Enterococcus faecium. The results of the study indicate that red deer may play an important role in the environmental maintenance of zoonotic pathogens. A particularly important factor in the epidemiology of bacterial infections is the introduction of pathogens posing a risk to other animals and humans into the soil, plants and especially water, as contaminants together with faeces. Our study presents screening of potentially pathogenic bacteria in different populations of deer that were displaced under reintroduction programmes. Based on our own research and the literature data, it seems that wild ruminants play an important role in the maintenance of zoonotic pathogens and information about zoonoses from red deer will become increasingly important as deer populations continue to grow, especially in Europe.