No indication of arthropod-vectored viruses in mosquitoes (Diptera: Culicidae) collected on Greenland and Svalbard

Viruses transmitted to vertebrates via arthropod vectors (so-called arboviruses) include many important pathogens such as dengue virus, Zika virus, and Sindbis virus. Mosquitoes represent the major vectors of many of these arboviruses and occur in all climatic zones, including the Arctic. The focal species, Aedes nigripes (Diptera: Culicidae), is the most widely distributed mosquito species in the Arctic. We screened over 11,000 specimens collected between 2012 and 2016 on Greenland (Kangerlussuaq) and Svalbard (Petuniabukta) for the presence of arboviruses which have previously been reported in latitudes up to 70°N. Assays for arbovirus detection using RT-PCR with primers specific for the genera Alphavirus (family Togaviridae), Orthobunyavirus, Phlebovirus (Bunyaviridae), Flavivirus (Flaviviridae), and Orbivirus (Reoviridae) were negative for all specimens. Similar results were recently obtained in a screening focused on tick-borne pathogens on Svalbard. The findings suggest that the circulation of arboviruses at studied localities is currently negligible or nonexistent, possibly due to dispersal, climate, or biotic restrictions. However, global climate change could enhance vector abundance and activity, introduction of invasive host species, and increase in tourism which then could lead to emerging arbovirus outbreaks in the future, with considerable impact on local ecosystems.