Epidemiology of West Nile Virus (WNV) in Canadians

  • 5 WNV lineages identified based on genomic phylogeny
  • Canada represents the northernmost range of WNV in North America
  • 2001: First positive WNV indicator in Canada, virus was detected in birds and mosquitoes in Ontario
  • 2002: 394 human cases in Ontario and 20 human cases in Quebec
  • 2003: WNV spread quickly to the prairie provinces with a proportion of the cases resulting in West Nile Neurologic Syndrome (WNNS) that occured mostly in the southern parts of Canada.
  • 2007: 2nd major outbreak in Canada! 1456(113 WNNS) cases in Saskatchewan, 587(72 WNNS) cases in Manitoba, and 318(21 WNNS) cases in Albera
  • 2009: Long-delayed range expansion of WNV into British Columbia. 2 cases in humans, 10 positive mosquito pools and 3 cases in horses detected by provincial surveillance

    Engler, O., et al. (2013) European Surveillance for West Nile Virus in Mosquito Populations. Int. J. Environ. Res. Public Health. 10:4869-95.
    Roth, D. et al.(2010) West Nile Virus Range Expansion into British Columbia. Emerg Infect Dis. 16(8):1251-8.