Jamestown Canyon and snowshoe hare virus seroprevalence in New Brunswick

Abstract

Background: Jamestown Canyon virus (JCV) and snowshoe hare virus (SSHV) are wide-ranging mosquito-borne arboviruses in the California serogroup viruses (CSGV) that are known to circulate in New Brunswick. Despite potential for debilitating central nervous system manifestations, the prevalence of human exposure to these viruses in New Brunswick is unknown. The goal of this study was to quantify rates of human exposure in New Brunswick to these neglected arboviruses. Methods: A retrospective, anonymized provincial serosurvey was performed using a stratified random sample of residual sera submitted between May 2015 and August 2016. To determine the seroprevalence of JCV and SSHV, competitive enzyme-linked immunosorbent assay–positive samples were confirmed positive using plaque-reduction neutralization testing (PRNT). Results: A total of 452 serum samples were screened. The seroprevalence of antibodies against CSGV was estimated to be 31.6% (95% CI 27.4% to 36.1%) with 143 positive samples. PRNT results indicated that most single virus exposures were due to JCV (38 of 143; 26.6%) rather than SSHV (3 of 143; 2.1%). The species of CSGV that the remaining 102 seropositive people were exposed to could not be precisely determined. Conclusions: The prevalence of human exposure to CSGV is high but comparable to rates observed in other Atlantic Canadian jurisdictions. Studies such as this provide important baseline epidemiological data regarding the risk of exposure to these neglected arboviruses. SSHV and JCV should be considered in the differential diagnosis for undiagnosed febrile and neuroinvasive illness during mosquito season, particularly when testing for common aetiologies is negative or inconclusive.

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

“…Urbanization and international travel, for example, heighten transmission risks and the (re)introduction of mosquito-borne diseases (MBDs) 3 , 4 . 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.…”

Jamestown Canyon virus (Bunyavirales: Peribunyaviridae) vector ecology in a focus of human transmission in New Hampshire, USA

“…Over 22 states have reported human cases, presumed to be locally acquired (CDC ArboNET 2022). Reports of JCV antibody prevalence in humans range from 4% to >20% across North America from southwestern US National Parks to New Brunswick, CA (Mayo et al 2001, Kosoy et al 2016, Mincer et al 2021). However, human case reporting and mosquito vector surveillance are not uniformly conducted across the United States.…”

Jamestown Canyon virus comes into view: understanding the threat from an underrecognized arbovirus

“…Antibodies increased with age in studies that analyzed this variable, suggesting long-term endemic transmission of JCV within these communities (Walters et al 1999, Patriquin et al 2018, Mincer et al 2021). Seropositivity was statistically higher in males in 3 surveys (Grimstad et al 1986a, Patriquin et al 2018, Mincer et al 2021) but there was no difference among sexes in native populations from Alaska (Walters et al 1999). Although reported clinical cases are rare, serological evidence suggests that residents are frequently exposed to JCV and that most infections are mild or asymptomatic.…”

“…Underlying symptomatic cases is a much larger population of exposed individuals as revealed by serosurveys of human populations. Seropositivity to JCV among humans was reported at 28% in Michigan (Grimstad et al 1986a), 4–10% in CT (Mayo et al 2001), 18% in Alaska (Walters et al 1999), 9–24% in Quebec (Sampasa-Kanyinga et al 2013), 21% in Nova Scotia (Patriquin et al 2018), and 27% in New Brunswick (Mincer et al 2021). Antibodies increased with age in studies that analyzed this variable, suggesting long-term endemic transmission of JCV within these communities (Walters et al 1999, Patriquin et al 2018, Mincer et al 2021).…”

“…Seropositivity to JCV among humans was reported at 28% in Michigan (Grimstad et al 1986a), 4–10% in CT (Mayo et al 2001), 18% in Alaska (Walters et al 1999), 9–24% in Quebec (Sampasa-Kanyinga et al 2013), 21% in Nova Scotia (Patriquin et al 2018), and 27% in New Brunswick (Mincer et al 2021). Antibodies increased with age in studies that analyzed this variable, suggesting long-term endemic transmission of JCV within these communities (Walters et al 1999, Patriquin et al 2018, Mincer et al 2021). Seropositivity was statistically higher in males in 3 surveys (Grimstad et al 1986a, Patriquin et al 2018, Mincer et al 2021) but there was no difference among sexes in native populations from Alaska (Walters et al 1999).…”