An expected consequence of climate warming is an expansion of the geographical distribution of biting insects and associated arthropod-borne viruses (arboviruses). Emerging and re-emerging arboviruses that can affect human and animal health are likely to pose significant consequences for Northern communities where access to health resources is limited. In the North American Arctic, little is known about arboviruses. Thus, in 2019, we sampled biting insects in Nunavik, Northern Québec (Kuujjuaq), Nunavut (Igloolik, Karrak Lake and Cambridge Bay), Northwest Territories (Igloolik and Yellowknife) and Alaska (Fairbanks). The main objective was to detect the presence of California serogroup (CSG) viruses– a widespread group of arboviruses across North America and that are known to cause a wide range of symptoms, ranging from mild febrile illness to fatal encephalitis. Biting insects were captured twice daily for a 7-day period in mid-summer, using a standardised protocol consisting of 100 figure-eight movements of a sweep net. Captured specimens were separated by genus (mosquitoes) or by superfamily (other insects) and then grouped into pools of 75 by geographical locations. In total, 5079 Aedes mosquitoes and 1014 Simulioidae flies were caught. We report the detection of CSG viruses RNA in mosquitoes captured in Nunavut (Karrak Lake) and Nunavik (Kuujjuaq). We also report, for the first time in North America, the presence of CSG viruses RNA in Simulioidae flies. These results highlight the use of biting insects for tracking any future emergence of arboviruses in the North, thereby providing key information for public health in Northern communities.

气候变暖的一个预期后果是叮咬昆虫和相关节肢动物传播病毒（虫媒病毒）的地理分布范围扩大。可影响人类和动物健康的新出现和重新出现的虫媒病毒可能会对获取卫生资源有限的北部社区造成重大影响。在北美北极地区，人们对虫媒病毒知之甚少。因此，在 2019 年，我们在努纳维克、魁北克北部（Kuujjuaq）、努纳武特（伊格卢利克、卡拉克湖和剑桥湾）、西北地区（伊格卢利克和耶洛奈夫）和阿拉斯加（费尔班克斯）采样了叮咬昆虫。主要目标是检测加利福尼亚血清群 (CSG) 病毒的存在，这是一种遍布北美的广泛传播的虫媒病毒群，已知会引起多种症状，从轻微的发热性疾病到致命的脑炎。使用由 100 次八字形扫网运动组成的标准化方案，在仲夏的 7 天内每天捕获两次叮咬昆虫。捕获的标本按属（蚊子）或总科（其他昆虫）分开，然后按地理位置分组为 75 个。共计 5079捕获了伊蚊和 1014 只拟蝇。我们报告了在努纳武特 (Karrak Lake) 和努纳维克 (Kuujjuaq) 捕获的蚊子中检测到 CSG 病毒 RNA。我们还首次在北美报告了拟蝇科苍蝇中 CSG 病毒 RNA 的存在。这些结果强调了使用叮咬昆虫来跟踪北方未来任何虫媒病毒的出现，从而为北方社区的公共卫生提供关键信息。