Disease Alerts

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

Horse 1: 
Age: 24; Gender: Mare; Breed: Thoroughbred (TB); Onset of Clinical Signs: 7/7/2026; Clinical Signs: This mare developed acute ataxia in all four limbs with muscle fasciculations and hyperesthesia on July 7. Clinical signs progressed and she was euthanized. Nasal swab and blood samples were positive for EHV-1 by PCR. There was no history of recent travel.; Horse Status: Euthanized; 

Comments: The facility owner, working with their veterinarian, has instituted voluntary animal movement restrictions and biosecurity protocols. To see past and present EHV-1 neurologic (EHM) cases in Ontario go to: https://www.oahn.ca/resources/ontario-equine-disease-alerts/ and enter the disease surveillance portal;

Number Confirmed: 1; 
Number Exposed: 2; 
Previous Alerts: 5044

Number Confirmed: 1; 
Number Exposed: 7; 

Horse 1: 
Age: 25; Gender: Mare; Breed: Pony; Onset of Clinical Signs: 6/29/2026; Clinical Signs: This mare developed sudden neurologic signs (ataxia , urine dribbling) on the evening of June 29. Her signs progressed the next day and she was euthanized. The mare had been at a schooling show in the Regional Municipality of Peel on June 28. The mare was kept outside at all times. The risk to other horses competing at the show is considered low, however, out of an abundance of caution, owners or custodians of horses attending the show should monitor the health of their horses over the next 14 days, including rectal temperature, which should be interpreted in the context of the extreme heat wave the region is experiencing. Owners should contact their veterinarian with any concerns about their horse.; Horse Status: Euthanized; 

Comments: The facility owner, working with their veterinarian, has instituted voluntary animal movement restrictions and biosecurity protocols. To see past and present EHV-1 neurologic (EHM) cases in Ontario go to: https://www.oahn.ca/resources/ontario-equine-disease-alerts/ and enter the disease surveillance portal.;

Number Confirmed: 1; 
Number Suspected: Unknown; 
Number Exposed: 7; 
Number Euthanized: 1; 
Facility Type: Horse Rescue; 

Horse 1: 
Age: Weanling; Gender: Mare; Breed: Donkey; Usage: Pet; Onset of Clinical Signs: 6/17/2026; Clinical Signs: Patient presented for extreme lethargy and increased respiratory effort. On presentation the patient had fever, increased resp rate and effort, and an elevated heart rate. Patient was minimally responsive to external stimuli. Patient had diarrhea and cyanotic mucous membranes.; Confirmation Date: 6/24/2026; Horse Status: Euthanized; Vaccination Status: Status Unknown;

Number Confirmed: 1; 
Number Exposed: 2; 
Facility Type: Private Facility; 

Horse 1: 
Clinical Signs: The mare presented with clinical signs of vestibular disease, including head tilt and circling to the left. Diagnostics were returned negative for EPM, but positive to EHV-1 on PCR of whole blood. Two other horses are exposed, but are not showing clinical signs. The mare has improved with treatment.; Confirmation Date: 6/19/2026; Horse Status: Affected And Alive;

Number Confirmed: 1; 
Number Exposed: 15; 
Number Euthanized: 1; 

Horse 1: 
Age: 18; Gender: Gelding; Breed: Thoroughbred (TB); Onset of Clinical Signs: 6/6/2026; Clinical Signs: This gelding developed edema of all four limbs on June 6. His signs progressed to acute hindlimb ataxia and bladder paralysis and he was taken to an equine referral hospital that day. He became recumbent on June 8 and was euthanized. Nasal swab was positive for EHV-1 by PCR.; Confirmation Date: 6/8/2026; Horse Status: Euthanized; Vaccination Status: Vaccinated;

Comments: The facility owner, working with their veterinarian, has instituted voluntary animal movement restrictions and biosecurity protocols. To see past and present EHV-1 neurologic (EHM) cases in Ontario go to: https://www.oahn.ca/resources/ontario-equine-disease-alerts/ and enter the disease surveillance portal;

Number Confirmed: 1; 
Number Exposed: 18; 
Number Euthanized: 1; 
Facility Type: Boarding Facility; 
Comments: All trace premises have been contacted.;

Number Confirmed: 1; 
Number Exposed: 18; 

Horse 1: 
Age: 18; Gender: Gelding; Breed: Oldenburg; Onset of Clinical Signs: 5/19/2026; Clinical Signs: acute clinical signs; Horse Status: Affected And Alive; 

Comments: The 18 remaining horses and ponies on the premises are under quarantine and being monitored for sickness. No recent horse movement has occurred by this herd, making the risk of disease spread from this case very low.;