Outbreaks | Equine Disease Communication Center

Updates on current disease outbreaks are listed here as they occur and will include the date listed, disease name, location and current status. Specific premises will not be named but the general location by town, county and state will be listed. When locations, events or horses are at risk they will be listed. Updates will be posted as they are received.

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West Nile Virus

Grey County, ON

Outbreak Identifier: 7155

Alert ID: 4678

October 23, 2025

Confirmed Case(s) - No Quarantine

Source: OMAFA

Number Confirmed: 1;
Number Exposed: Unknown;
Facility Type: Farm;

Horse 1:
Age: 17; Gender: Gelding; Breed: Standardbred; Onset of Clinical Signs: 9/27/2025; Clinical Signs: This gelding developed neurologic signs (hindlimb ataxia) on September 27. He tested positive for WNV.; Confirmation Date: 10/14/2025; Horse Status: Recovering; Vaccination Status: Unvaccinated;

Comments: This is the 9th confirmed case of equine WNV in Ontario this year . To see past and present WNV cases in Ontario go to: https://www.oahn.ca/resources/ontario-equine-disease-alerts/ and enter the disease surveillance portal;;;

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