Breaking News
Learn More About the EDCC
Learn More

Disease Alerts

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.



Middlesex County, ON
Outbreak Identifier: 7256
Alert ID: 4817
January 03, 2026
Confirmed Case(s) - Voluntary Quarantine

Number Confirmed: 7; 
Number Suspected: 4; 
Comments: 

Update: The Strangles outbreak at this Standardbred training facility was first confirmed on Dec 9, 2025. As of January 2, 2026 there have been 7 confirmed and 4 suspected cases of Strangles at the facility. The first group of affected horses (3 confirmed, 2 suspected) have recovered and are being tested at one isolation facility. The second group of affected horses (4 confirmed and 2 suspected) were voluntarily moved to a second isolation facility on January 2, 2026. All affected horses were housed in Barn 1 at the facility. 

Timeline: On Dec 8, 2025, all foot traffic ceased between the affected quadrant and remainder of Barn 1 with physical barriers in place. The 14- day voluntary animal movement restrictions began with twice daily temperature monitoring of the horses and biosecurity measures used. During this time, Barns 2 and 3 at the facility carried on business as usual and were permitted to race as they had had no evidence of disease and no direct or indirect contact with the Strangles cases in Barn 1. These racehorses posed no increased risk to the industry. Between Dec 16 and 20, two young horses developed clinical signs of respiratory disease in Barn 1. Both tested negative for Strangles (S. equi) but positive for the same respiratory virus. Similar (and suspected) upper respiratory viral infections had been circulating within the Standardbred yearling population according to local racehorse veterinarians. This circulating respiratory virus was an unexpected challenge. On Dec 23, the 14-day voluntary movement restrictions ended as no further Strangles cases could be confirmed. The Alcohol and Gaming Commission of Ontario, who regulate the industry, permitted horses to race. However, due to weather cancellations, NO horses from Barn 1 raced between Dec 23 and Dec 29. During the week of Dec 22-27, more young horses in the same shedrow of Barn 1 continued to have fevers, nasal discharge and lymph node swelling which were initially thought to be due to the circulating virus. However, these lymph nodes began to abscess and drain and Strangles (S. equi) was confirmed on Dec 29, including in a yearling that previously tested negative. The trainers in Barn 1 promptly restricted animal movement again. Trainers in Barn 2 also restricted animal movement as a precaution as there had been some common staff managing horses in barn 1 and 2 during this week. Barn 3 at the facility has remained independent of the other two barns, has biosecurity protocols in place and has no indirect or direct contact with the Strangles cases. On Dec 29, a 4-year-old racehorse in Barn 1, with a different trainer, developed a single swollen lymph node (no fever, no nasal discharge). On Jan 2, all confirmed and suspected Strangles cases from Barn 1 were isolated at an off-site facility. Trainers in Barn 1 are continuing to voluntarily restrict movement of their horses and monitor them for signs of disease. The attending veterinarians will continue to manage this challenging outbreak with the cooperation of trainers at the facility. OMAFA will continue to provide advice as requested. The Alcohol and Gaming Commission of Ontario is the body that determines the eligibility of horses to race.; 
Previous Alerts: 4789

Adams County, CO
Outbreak Identifier: 7278
Alert ID: 4816
December 31, 2025
Confirmed Case(s) - Official Quarantine

State Veterinarian's Office

Number Confirmed: 1; 
Number Exposed: 13; 
Number Euthanized: 1; 
Facility Type: Training Facility; 

Horse 1: 
Age: 5; Gender: Mare; Breed: Quarter Horse (QH); Usage: Racing; Clinical Signs: Unthrifty, poor body condition, tested for interstate movment requirements; Confirmation Date: 12/23/2025; Horse Status: Euthanized; 

Comments: Confirmatory testing for cohorts is pending.;

Santa Cruz County, AZ
Outbreak Identifier: 7277
Alert ID: 4815
December 30, 2025
Confirmed Case(s) - Official Quarantine

United States Department of Agriculture Animal and Plant Health Inspection Service

Comments: Since the last situation report (12/9/2025), there has been one (1) new confirmed VSVpositive equine premises identified in Arizona (Santa Cruz County). All confirmed cases in the 2025 outbreak have been vesicular stomatitis New Jersey virus (VSNJV) serotype. Since the last situation report (12/9/2025), 1 affected premises in Santa Cruz County was released from quarantine. Premises that have diagnostic laboratory confirmation of VSV are categorized as confirmed positive premises. Once a county is confirmed as VSV-positive, new equine premises presenting with clinical signs of VSV in that county are not required to be tested for confirmation of the disease, but the premises will be quarantined and classified as a presumptive positive premises. Premises may also be classified as presumptive positive if clinical animals on the premises fail to meet confirmed case definition, but there is diagnostic laboratory evidence of recent VSV infection.; Confirmed and presumptive positive premises are quarantined for at least 14 days from the onset of lesions in the last affected animal on the premises. 

For more information, go to https://www.aphis.usda.gov/sites/default/files/vsv-sitrep-12-30-25.pdf

Cecil County, MD
Outbreak Identifier: 7276
Alert ID: 4814
December 29, 2025
Confirmed Case(s) - Official Quarantine

Maryland Department of Agriculture

Number Confirmed: 1; 
Number Exposed: 27; 
Facility Type: Training Facility; 

Horse 1: 
Age: 4; Gender: Mare; Breed: Warmblood (WB); Usage: Trail Riding; Onset of Clinical Signs: 12/29/2025; Clinical Signs: Febrile. Neurological deficits including hindlimb lameness; urine dribbling.; Confirmation Date: 12/29/2025; Horse Status: Quarantined; Vaccination Status: Status Unknown;

Hillsborough County, FL
Outbreak Identifier: 7259
Type: EHV-1
Alert ID: 4813
December 29, 2025
Quarantine Released

Florida Department of Agriculture and Consumer Services

Number Confirmed: 1; 
Number Exposed: 74; 
Facility Type: Racetrack; 

Horse 1: 
Age: 2; Gender: Filly; Breed: Thoroughbred (TB); Usage: Racing; Onset of Clinical Signs: 12/8/2025; Confirmation Date: 12/10/2025; 

Comments: The quarantine has been released as of Dec. 29, 2025.; 
Previous Alerts: 4792

St Clair County, MI
Outbreak Identifier: 7275
Alert ID: 4812
December 29, 2025
Confirmed Case(s) - Voluntary Quarantine

Michigan Department of Agriculture and Rural Development

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

Horse 1: 
Age: 13; Gender: Gelding; Breed: Quarter Horse Cross; Onset of Clinical Signs: 12/15/2025; Clinical Signs: Fever, nasal discharge, increased respiratory rate,; Confirmation Date: 12/24/2025; Horse Status: Affected And Alive; Vaccination Status: Status Unknown;

Eddy County, NM
Outbreak Identifier: 7217
Type: EHV-1
Alert ID: 4811
December 24, 2025
Quarantine Released

State Veterinarian

Number Confirmed: 2; 
Number Exposed: 3; 
Comments: All of our hold orders were released around 12/7 to 12/10. Our last quarantine was released on 12/21. As of right now, we have no active cases.; 
Previous Alerts: 4743

Dona Ana County, NM
Outbreak Identifier: 7206
Type: EHV-1
Alert ID: 4810
December 24, 2025
Quarantine Released

State Veterinarian

Number Confirmed: 1; 
Number Exposed: 2; 
Comments: All of our hold orders were released around 12/7 to 12/10. Our last quarantine was released on 12/21. As of right now, we have no active cases.; 
Previous Alerts: 4732

Palm Beach County, FL
Outbreak Identifier: 7274
Alert ID: 4809
December 23, 2025
Confirmed Case(s) - Official Quarantine

Florida Department of Agriculture and Consumer Services

Number Confirmed: 1; 
Number Exposed: 52; 
Facility Type: Boarding Facility; 
Comments: All traces have been conducted.;

Larimer County, CO
Outbreak Identifier: 7198
Type: EHV-1
Alert ID: 4808
December 23, 2025
Quarantine Released

State Veterinarian's Office

Number Confirmed: 1; 
Number Exposed: Unknown; 
Comments: Notice of quarantine release; 
Previous Alerts: 4730, 4723