New records of California serogroup viruses in Aedes mosquitoes and first detection in simulioidae flies from Northern Canada and Alaska

Abstract

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.

Widespread Exposure to Mosquitoborne California Serogroup Viruses in Caribou, Arctic Fox, Red Fox, and Polar Bears, Canada

“…Furthermore, we recently detected JCV and SSHV in Aedes sp. mosquitoes and biting midges collected in northern Québec ( 11 ), further confirming circulation of CSG viruses in northern vectors. Potential reservoirs in southern Canada and the United States are cervids for JCV and rodents and lagomorphs for SSHV ( 5 ).…”

A cost-effective RNA extraction and RT-qPCR approach to detect California serogroup viruses from pooled mosquito samples

“…The pooled tubes encompassed varying quantities of mosquitoes, ranging from 1 to 50 individuals. 2018 samples were first screened for CSGv via RT-qPCR at the NML (see 8 for NML’s diagnostic framework). The mosquito homogenates were subsequently shipped to Carleton University for method development.…”

“…The mosquito homogenates were subsequently shipped to Carleton University for method development. The NML also processed and extracted RNA from the 2019 samples using an in-house adapted QIAGEN™ RNeasy® method (see 8 ), but those extracts were screened for CSGv at Carleton University due to the SARS-CoV-2 diagnostics focus at the NML post-2020. All method development was done directly via the mosquito homogenate samples sent by the NML.…”

“…In Canada, endemic pathogens like West Nile virus, eastern equine encephalitis virus, and California serogroup viruses (CSGv) are on the rise 3 , 5 , 6 . Some studies have demonstrated CSGv prevalence in mosquitoes, animals, and humans 5 – 8 , including a 2018–2019 MBD surveillance program in Southeastern Ontario, Canada, which identified several CSGv-positive mosquito pools. Despite this surge, CSGv cases are underreported, indicating a pressing need for enhanced surveillance and testing 3 , 9 .…”

Relationships between water quality and mosquito presence and abundance: a systematic review and meta-analysis

“…Mosquito-borne diseases (MBDs), such as malaria, dengue, chikungunya, and yellow fever, are the leading cause of approximately 1 million deaths and over 700 million infections attributed to vector-borne diseases annually (World Health Organisation 2020). High MBD prevalence is most common in tropical and arid regions; however, climate change is broadening the geographic distribution of MBD globally (Reiter 2001, Parkinson et al 2014, Villeneuve et al 2021). In addition to climate factors, land use is a major contributor to the dispersal of mosquito arboviruses (Norris 2004).…”