20 May 2026
In a historic and worrying development for Arctic wildlife, scientists have confirmed the first-ever detection of highly pathogenic avian influenza (HPAI) in a polar bear in Europe. The virus was identified in a one-year-old male polar bear, as well as in a walrus, at the northern end of Spitsbergen, the largest island in the Svalbard archipelago. The discovery was made following a field investigation initiated in mid-May, after local tourist guides spotted the carcasses of both animals in Raudfjorden. Furthermore, two additional polar bears in the area were observed exhibiting signs of hindlimb lameness. While such neurological symptoms can stem from various causes, they are consistent with conditions previously seen in predators infected with bird flu or rabies. Following the report, experts from Norway’s Veterinærinstituttet (the Norwegian Veterinary Institute) traveled to the remote location via helicopter to collect biological samples. Laboratory analysis subsequently confirmed the presence of the highly pathogenic H5N5 subtype of the avian influenza virus in brain samples from both the polar bear and the heavily decomposed walrus. Testing for the rabies virus came back negative. While the H5N5 subtype has been detected on Svalbard before, first in wild seabirds in 2022, followed by a walrus in 2023 and Arctic foxes in 2025, this marks the very first time the virus has crossed into a polar bear in Norway or anywhere else in Europe. Globally, avian influenza in polar bears has only been scientifically documented once before, in Alaska in October 2023.
Norway’s Veterinærinstituttet has announced that it will conduct further genetic analysis on the detected virus to determine whether it has acquired specific mutations that indicate an adaptation to mammals.
