Using residual serum samples from Nova Scotia, Canada, we found that 87.8% of tested deer and an estimated 20.6% of the human population were infected with Jamestown Canyon virus. Human seropositivity reached 48.2% in 1 region. This virus may be an underrecognized cause of disease in Nova Scotia.
Keywords: Atlantic; Bunyaviridae; California serogroup; Canada; Jamestown Canyon virus; Nova Scotia; arbovirus; bunyavirus; seroprevalence; viral encephalitis; viral meningitis; viruses; zoonotic.