Strangles (Streptococcus equi) has been confirmed in the District of Sudbury, Ontario. A pregnant 10 year old Quarter Horse mare, bought at an auction in Alberta, developed a submandibular abscess on December 1, 2025, 16 days after arriving in Ontario. She is isolated from others on the farm. Pus from the abscess tested positive for S. equi.
The facility owner, working with their veterinarian, has instituted voluntary animal movement restrictions and biosecurity protocols. To see past and present Strangles cases in Ontario go to: https://www.oahn.ca/resources/ontario-equine-disease-alerts/ and enter the disease surveillance portal.