Pathogen is mainly known for causing disease in immunocompromised humans and newborns
In 2019, an acute die-off was reported among European hares (Lepus europaeus) in northeastern Austria. A study published in Letters in Applied Microbiology shows that the most likely cause was typhlocolitis, resulting from an infection with the bacterial pathogen Cronobacter turicensis. This is thought to be the first report of clinical infection caused by a member of the genus Cronobacter in wild animals.
The study, led by the University of Veterinary Medicine, Vienna (Vetmeduni), investigated nine hares that died in autumn 2019. All nine showed very similar lesions in necropsy and histopathology. Five of the animals were found to be infected with C. turicensis, while the other four were infected with unrelated bacteria.
The bacterial genus Cronobacter, which currently comprises seven species, is primarily known as a ubiquitous, opportunistic pathogen that can contaminate several types of food products. Particularly dangerous are C. sakazakii and C. malonaticus, which are involved in most clinical Cronobacter infections in humans, causing severe symptoms such as blood poisoning, necrotising enteritis and meningitis.
The researchers say their study demonstrates that C. turicensis could be associated with epidemiologically related cases of typhlocolitis in European hares. “Due to the potential of this bacterium to inflict severe disease in humans, the risk of a spillover should be kept in mind, especially for those people in direct contact with hares, such as hunters, farmers or veterinarians,” says the study’s first author, Annika Posautz of the Research Institute of Wildlife Ecology at Vetmeduni.
The researchers recommend a more detailed investigation of wild animal populations: “The risk of a spillover of the bacterium Cronobacter turicensis highlights the importance of investigating the general role of wild animals as a reservoir of potentially pathogenic C. turicensis strains”, say Annika Posautz and Igor Loncaric, the study’s last author.
Article: Posautz, A., Szostak, M. P., Cabal Rosel, A., Allerberger, F., Stöger, A., Rab, G., Feßler, A. T., Spergser, J., Kübber-Heiss, A., Schwarz, S., Forsythe, S. J., Ruppitsch, W., & Loncaric, I. (2022). Outbreak of Cronobacter turicensis in European brown hares (Lepus europaeus). Letters in Applied Microbiology, advance online publication, doi: 10.1111/lam.13685