Eastern Equine Encephalitis (EEE) has been confirmed in the United Counties of Stormont, Dundas and Glengarry, Ontario. On September 5, 2024, a 3 year old filly was noticed to be ataxic with an abnormally quiet demeanor and fever (41C). Despite supportive treatment, she died on September 7, 2024. EEE was confirmed on September 30, 2024. The horse was not vaccinated against EEE. This is the 19th case of equine EEE in Ontario this year.