Volume: 5, 2026
5th International PhD Students’ Conference at the University of Life Sciences in Lublin, Poland:
ENVIRONMENT – PLANT – ANIMAL – PRODUCT
Abstract number: A029
DOI: https://doi.org/10.24326/ICDSUPL5.A029
Published online: 22 April 2026
Virulence of superbugs, Escherichia coli as risk factors in free-living animals
Wojciech Ospałek*, Łukasz Wlazło, Małgorzata Targońska-Karasek and Bożena Nowakowicz-Dębek
Department of Animal Hygiene and Environmental Hazards, University of Life Sciences in Lublin, 13 Akademicka St., 20-950 Lublin, Poland
* Corresponding author: wojciech.ospalek@up.edu.pl
Zoonotic bacteria currently pose a significant threat to public health, resulting from the increasing interpenetration of human and wild animal habitats. Wild ruminants play a particularly important epidemiological role. As asymptomatic carriers, they can constitute both a primary and secondary source of pathogenic microorganisms. Importantly, they also act as a reservoir and vector for the transmission of genes associated with antimicrobial resistance and virulence, contributing to their spread in the natural environment.
The significance of this phenomenon is growing due to the increasing entry of wild animals into highly urbanized areas, which increases the risk of direct and indirect contact with humans, livestock, and environmental components. This creates favorable conditions for the circulation of microorganisms and the exchange of genetic material between various ecological niches, both natural and anthropogenic.
Among zoonotic bacteria, Escherichia coli is particularly important, being widespread in the environment due to its presence in the gastrointestinal tract of animals and its well-known pathogenic potential. E. coli virulence is associated with the presence of numerous factors, including genes involved in biofilm formation, such as aggR, fimH, bolA, csgD, and luxS. Additionally, some strains possess the ability to produce Shiga toxins and are classified as STEC, with key virulence genes including stx1, stx2, eaeA, and hlyA. Another significant problem is growing antimicrobial resistance. In the case of E. coli, the presence of extended-spectrum β-lactamases (ESBLs) is of particular concern, but resistance to carbapenems, third-generation cephalosporins, sulfonamides, aminoglycosides, tetracyclines, and fluoroquinolones, including plasmid-mediated mechanisms (PMQR), has also been observed.
The epidemiological significance of this bacterium is further enhanced by its ability to survive in the environment. Escherichia coli can persist in soil for extended periods due to its tolerance to fluctuations in temperature and humidity, which increases the risk of indirect transmission. Consequently, free-living animals should be considered not only as passive reservoirs but also as active players in the maintenance, evolution, and spread of pathogenic and resistant microbial populations in the environment.
Keywords: Escherichia coli; zoonotic bacteria; wild ruminants; antibiotic resistance; virulence genes; environmental transmission
How to cite
Ospałek W., Wlazło Ł., Targońska-Karasek M., Nowakowicz-Dębek B., 2026. Virulence of superbugs, Escherichia coli as risk factors in free-living animals. In: 5th International PhD Students’ Conference at the University of Life Sciences in Lublin, Poland: Environment – Plant – Animal – Product. https://doi.org/10.24326/ICDSUPL5.A029