A dead male polar bear and a walrus found on the Arctic archipelago of Svalbard have tested positive for the H5N5 strain of highly pathogenic avian influenza, marking the first confirmed cases of bird flu in polar bears in Europe, Norwegian authorities announced Tuesday. The Norwegian Veterinary Institute (NVI) confirmed the detection in samples collected from the animals in mid-May, adding that the discovery underscores the expanding geographic reach of avian influenza in the Arctic.
The infected bear, estimated to be about one year old, and the walrus were discovered in the same region, approximately 1,000 kilometers (620 miles) from the North Pole. While the NVI has not yet determined the precise route of transmission, the presence of H5N5 in both animals suggests potential spillover from infected seabirds or marine mammals, a pattern observed in other Arctic wildlife populations in recent years. The institute emphasized that the findings are part of an ongoing surveillance program monitoring avian influenza in Arctic species, which has seen increasing detections across the region since 2022.
Svalbard, a Norwegian-administered territory located between mainland Norway and the North Pole, serves as a critical habitat for Arctic wildlife, including polar bears, walruses, and seabird colonies. The archipelago’s remote location and harsh climate typically limit human contact with wildlife, but climate change and shifting migration patterns have raised concerns among scientists about the potential for disease transmission between species. The NVI’s latest report does not indicate whether the virus poses an immediate risk to human health, though avian influenza strains like H5N5 have historically shown limited human-to-human transmission but can cause severe illness in mammals.
The discovery follows a broader trend of avian influenza detections in Arctic wildlife, including seals, reindeer, and seabirds, across Norway, Greenland, and Canada. In January 2024, the Norwegian Food Safety Authority reported H5N1 cases in reindeer herds in Finnmark, Norway’s northernmost county, prompting culling measures to contain the outbreak. While the H5N5 strain identified in Svalbard is distinct from the H5N1 variant, both belong to the same family of highly pathogenic avian influenza viruses, raising questions about whether the Arctic’s ecological systems are becoming more susceptible to viral spread.
Norwegian officials have not yet issued public health advisories related to the Svalbard findings, though the NVI has advised local researchers and indigenous communities to monitor wildlife for signs of illness. The Norwegian Environment Agency, which oversees Arctic conservation efforts, stated in a statement that the agency is coordinating with international partners, including the World Organisation for Animal Health (WOAH), to assess the broader implications of the detection. The agency did not specify whether additional testing or containment measures would be implemented in Svalbard.
The Arctic’s role as a sentinel for emerging infectious diseases has gained prominence in recent years, with climate-induced changes—such as thawing permafrost and altered migration routes—potentially facilitating the spread of pathogens. A 2023 study published in Nature highlighted how rising temperatures in the Arctic could increase the overlap between wildlife species, heightening the risk of cross-species transmission. The NVI’s confirmation of H5N5 in polar bears and walruses adds to a growing body of evidence suggesting that the region’s ecosystems may be undergoing unseen shifts in disease dynamics.
As of Tuesday, no further details were available on whether the virus had been detected in live polar bears or other wildlife in the region, though the NVI has pledged to release updated findings as they become available. The discovery comes amid heightened global surveillance for avian influenza, particularly after the H5N1 strain was detected in dairy cattle in the U.S. And Europe earlier this year, prompting concerns about potential zoonotic spillover. The Norwegian government has not yet commented on whether the Svalbard cases will influence domestic or international biosecurity protocols.
