Disease Alerts

Number Confirmed: 3; 
Number Suspected: 1; 
Number Exposed: Unknown; 
Facility Type: Training Facility; 

Horse 1: 
Breed: Standardbred; Clinical Signs: Two standardbreds, one who hasn't raced since June 2025 and another who last raced 11 days ago developed a high fever and submandibular lymph node swelling. Both tested positive for S. equi by PCR. A pony in the same shedrow with a draining abscess also tested positive for S. equi.; Confirmation Date: 12/10/2025; 

Comments: The infected horses are isolated and their care is being supervised by attending veterinarians. Trainers in the affected part of the barn have voluntarily withdrawn their horses from racing and are monitoring horses for fevers and the development of clinical signs of Strangles. Trainers at the facility are working with their veterinarians to institute biosecurity protocols.;

Number Confirmed: 1; 
Number Suspected: 4; 
Number Exposed: Unknown; 
Facility Type: Private Facility;

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

Horse 1: 
Age: 5; Gender: Mare; Onset of Clinical Signs: 11/23/2025; Clinical Signs: fever, swollen lymph nodes, respiratory noise; Confirmation Date: 11/25/2025; Horse Status: Recovering; Vaccination Status: Vaccinated;

Number Confirmed: 1; 
Number Exposed: 3; 
Facility Type: Private Facility; 

Horse 1: 
Age: 20; Gender: Mare; Breed: Haflinger; Clinical Signs: This mare developed a fever (39.9 C) and a draining tract under her jaw. The discharge was positive for S. equi by PCR.; Confirmation Date: 11/14/2025; 

Comments: 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.;

Number Confirmed: 1; 

Horse 1: 
Age: 5; Gender: Mare; Breed: Draft-cross; Clinical Signs: Fever, nasal discharge, lethargy; Confirmation Date: 11/19/2025; Horse Status: Affected And Alive; Vaccination Status: Status Unknown;

Comments: Horse acquired on November 7, 2025 from a dealer and was ill at the time. Date of onset unclear.;

Number Confirmed: 1; 
Number Exposed: 4; 

Horse 1: 
Age: 11; Gender: Mare; Breed: Quarter Horse (QH); Onset of Clinical Signs: 11/6/2025; Clinical Signs: enlarged submandibular lymph nodes, coughing, nasal discharge; Confirmation Date: 11/11/2025; Horse Status: Affected And Alive; Vaccination Status: Status Unknown;

Number Confirmed: 1; 
Number Exposed: 1; 
Facility Type: Private Facility; 

Horse 1: 
Age: Weanling; Gender: Colt; Breed: Oldenburg; Usage: Pleasure Riding; Onset of Clinical Signs: 11/5/2025; Confirmation Date: 11/10/2025; Horse Status: Quarantined; Vaccination Status: Status Unknown;

Number Exposed: 6; 
Number Euthanized: 1; 
Facility Type: Private Facility; 

Horse 1: 
Age: 24; Gender: Mare; Breed: Cross; Onset of Clinical Signs: 10/27/2025; Clinical Signs: swollen submandibular lymph nodes, thick, yellow /white nasal discharge, difficult breathing requiring a tracheostomy; Confirmation Date: 11/1/2025; Horse Status: Euthanized; Vaccination Status: Status Unknown;

Number Confirmed: 1; 
Number Suspected: Unknown; 
Number Exposed: Unknown; 

Horse 1: 
Age: 5; Gender: Mare; Breed: Standardbred; Clinical Signs: Dull and off feed; Confirmation Date: 11/4/2025; Horse Status: Euthanized; Vaccination Status: Status Unknown;

Comments: Horse was ill, underwent exploratory surgery, and was found to have multiple abdominal masses (abscesses).;

Number Confirmed: 2; 
Number Suspected: Unknown; 
Number Exposed: Unknown; 

Horse 1: 
Age: 22; Gender: Gelding; Breed: Draft; Confirmation Date: 10/27/2025; Horse Status: Recovering; Vaccination Status: Status Unknown;

Comments: Another horse at the premises was previously reported as a case (see alert 4657). This is a second, newly reported case at the premises. The sample was collected on October 22, 2025.; 
Previous Alerts: 4657