Monitoring the circulation of H5N1 in penguin colonies of the Ross Sea, Antarctica, during the 2024/2025 breeding season

H5N1 viruses of the 2.3.4.4b clade were introduced to the Antarctic Peninsula in February 2024, and have been maintained in this region overcoming the austral summer. This virus poses a threat to the continent's unique wildlife. Experts believe that the presence of this virus will accelerate the decline of species already suffering climate change, ultimately leading to an ecological catastrophe. The activities carried out in Antarctica under the Italian National Antarctic Research Programme (PNRA) were coordinated by the Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA). In view of the epidemiological scenario, ENEA and the Istituto Zooprofilattico Sperimentale delle Venezie (IZSVe) started a collaboration to develop protocols aimed at reducing the risk of infection for personnel deployed in Antarctica and to prevent the spread of the virus through fomite contamination. In Oct-Nov 2024, two IZSVe scientists conducted an active survey of selected penguin colonies in the Ross Sea, to map the presence of the virus and inform PNRA researchers of the countermeasures to be taken.