The Arctic Ecosystem is especially vulnerable to climate changes with several pathogens extending their distributions northerly and infecting hereinto naïve animal populations. At the same time, human driven activities change habitats, reduce resources or introduce additional stresses to several wild species, which leads to changes in infection patterns.
In aquatic ecosystems we observe infectious salmon anaemia and salmon pancreatic disease, two viral infections of salmonids, expanding north along the Norwegian coast as a result of, among others, higher water temperatures. Brucellosis, a well-known bacterial zoonosis of terrestrial animals, has also been found and isolated from seals and whales in Norwegian waters. More recently influenza related mortality in seals along southern Scandinavia raised new questions on spread of viral diseases.
In terrestrial ecosystems vector borne diseases are perhaps the main concern, as new vectors expand to higher latitudes. Tick borne encephalitis has been reported in the Arctic and we have identified cervids positive for TBE. Deer ked, a biting fly causing alopecia in moose but often also biting humans, continues to expand north and has been found to carry the zoonotic bacteria Bartonella spp. In reindeer/caribou we have observed outbreaks of infectious keratoconjunctivitis connected to alphaherpesvirus infections, with outbreaks likely linked to increased stress due to food shortages, habitat reductions, and changes in husbandry.
Any bird or mammal, including marine mammals, may potentially be infected by the protozoan parasite Toxoplasma gondii as shown by recent studies in the Svalbard high Arctic Archipelago. Also Rabies, caused by a lyssavirus, has been reported in the Svalbard Archipelago (last in 2011) with arctic foxes and reindeer being infected.
Increased awareness/research on emerging pathogens in the Arctic is paramount to understand the underlying infection biology mechanisms in this very quickly changing ecosystem and better predict disease emergence and evaluate mitigation options.