Since October 19, 2017, three cases of West Nile Virus in Frontenac County, Oxford County and the Regional Municipality of Halton have been reported to the Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA).

The horses included a gelding, a filly and a mare, ranging in age from two to 11 years old. Clinical signs ranged from hind end weakness, muscle fasciculations and hyperesthesia to ataxia.

All three are recovering under veterinary supervision. One horse was unvaccinated, one had not been vaccinated for three years, and one four-year-old had been vaccinated yearly since it was two.

The total number of cases reported in Ontario in 2017 is 21.