| Resum: |
Campylobacter and Salmonella are among the most commonly reported zoonoses in the EU and USA and have a strong impact on public health. Poultry are considered the main reservoir and source of infection for humans, but wild birds also play an important role in the epidemiology of these pathogens as they are usually asymptomatic carriers able to maintain infection and disperse them over long distances through migratory movements. Antarctic and sub-Antarctic regions were long thought to be protected from pathogens introduction, but recent studies have reported the presence of human and animal pathogens. To gain insight into the epidemiology of Campylobacter and Salmonella in seabirds inhabiting the Southern Ocean, 60 samples from different species of seabirds were sampled at Crozet, Amsterdam and Kerguelen islands during December 2020. We analysed them by direct PCR detection, obtaining an overall prevalence of 16. 67% for Campylobacter and 6. 67% for Salmonella. Furthermore, 54 Campylobacter isolates and 29 Salmonella isolates recovered from previous samplings were also included in the study to determine the Campylobacter species and Salmonella serovars, and to assess their genetic diversity by means of RFLP, PFGE and ERIC-PCR. Campylobacter species mainly included were C. lari and C. jejuni. Molecular typing techniques showed a high genetic diversity among the Campylobacter isolates, but also some clusters suggest a certain connectivity among Southern Ocean localities and a lack of host specificity. Salmonella serovars identified were Typhimurium, Enteritidis, Newport and Chincol, which showed a low genetic diversity. The presence of some Campylobacter genotypes and Salmonella serovars suggest that events of reverse zoonoses have occurred in the region. Our results highlight the role of seabirds, especially skuas, as disseminators of pathogens through their foraging and migration movements, as well as the need of further studies to assess the impact of human activity on the introduction of new pathogens in these remote areas. |
visitant ::
identificació
dir.
