A virus known to cause severe disease in marine mammals has been detected in whales in Arctic waters for the first time. This points to potential new health risks in a rapidly changing environment.
In a recent study published in BMC Veterinary Research, researchers identified cetacean morbillivirus in humpback whales, a sperm whale and a stranded pilot whale in northern Norway. The virus, part of the same genus as the measles virus in humans, has previously been linked to mass mortality events in dolphins and whales worldwide, but had not been reported above the Arctic Circle until now.
The study, conducted between 2016 and 2025, used minimally invasive methods to investigate free-ranging whales across the Northeast Atlantic, including northern Norway, Iceland and Cape Verde. Scientists collected blow samples (exhaled breath) using drones, alongside skin biopsies.
This approach enables pathogen detection in living animals and complements traditional investigations based on stranded individuals, which are often limited by decomposition and low reporting rates. The findings highlight the potential of drone-based sampling for disease surveillance in wild cetaceans.
The virus was detected in two groups of apparently healthy humpback whales, suggesting that infections may also occur without symptoms. In contrast, a sperm whale and a stranded pilot whale that tested positive showed clear signs of poor health, including skin lesions, parasite infestations and abnormal behaviour.
Morbilliviruses are known to weaken the immune system, increasing susceptibility to secondary infections. Herpesviruses were also detected in several groups of humpback whales, including cases of co-infection.
However, it remains unclear whether the virus was the primary cause of disease, contributed to it, or was present without causing severe effects.
The findings suggest that the lack of previous detections in Arctic regions may reflect limited surveillance rather than a true absence of the virus. Migratory species moving between tropical breeding grounds and Arctic feeding areas may facilitate its spread over long distances.
The study underscores the need for continued monitoring, as environmental change and human activity continue to increase pressure on Arctic marine ecosystems.
Léa Zinsli, PolarJournal