Disease Alerts

Number Confirmed: 10; 
Number Exposed: 25; 
Number Euthanized: 1; 
Comments: Quarantine is still in effect for the premises.; 
Previous Alerts: 4904

Number Confirmed: 2; 
Number Euthanized: 1; 
Comments: Case was originally posted Feb. 24, 2026;

Number Confirmed: 2; 
Number Exposed: 20; 
Facility Type: Boarding Facility; 

Horse 1: 
Age: 37; Gender: Gelding; Breed: Quarter Horse (QH); Onset of Clinical Signs: 3/1/2026; Confirmation Date: 3/4/2026; Horse Status: Quarantined; Vaccination Status: Status Unknown;

Previous Alerts: 4899

Comments: Since the last situation report (2/26/2026), there has been one (1) new confirmed VSV positive equine premises identified in Arizona (Yavapai County). All confirmed cases in the 2025-26 outbreak have been vesicular stomatitis New Jersey virus (VSNJV) serotype. Updates are as follows: Arizona • Yavapai County – 1 new equine premises confirmed VSV-positive • Since the last situation report (2/26/2026), no additional VSV-affected premises have been released from quarantine. Classification of Cases 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/livestock-poultry-disease/cattle/vesicular-stomatitis

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

Horse 1: 
Age: 17; Gender: Gelding; Breed: Oldenburg; Usage: Pleasure Riding; Onset of Clinical Signs: 2/22/2026; Clinical Signs: ADR, fever of 104F, progressed to nasal discharge from right nares. Abscess; Confirmation Date: 2/25/2026; Horse Status: Affected And Alive; Vaccination Status: Status Unknown;

Number Confirmed: 1; 
Number Exposed: 3; 
Number Euthanized: 1; 

Horse 1: 
Age: 16; Gender: Gelding; Breed: Tennessee Walking Horses; Clinical Signs: ataxia, trouble urinating, recumbent; Confirmation Date: 3/2/2026; Horse Status: Euthanized; 

Comments: A 16-year-old Tennessee Walker gelding from Santa Barbara County displaying neurologic signs was confirmed positive for Equine Herpesvirus Myeloencephalopathy (EHM) secondary to Equine Herpesvirus-1 (EHV-1). The gelding was euthanized due to severity of clinical signs. Three (3) potentially exposed horses at the home premises in Santa Barbara County were quarantined with enhanced biosecurity measures implemented. There has been no history of horses on or off the property in more than 30 days. CDFA has been onsite and will continue to actively monitor the situation.;

Number Confirmed: 1; 
Number Suspected: Unknown; 
Number Exposed: 10; 
Facility Type: Training Facility;

Number Confirmed: 1; 
Number Exposed: 3; 

Horse 1: 
Age: 10; Gender: Gelding; Breed: Quarter Horse (QH); Onset of Clinical Signs: 2/22/2026; Clinical Signs: dry cough, unilateral purulent nasal discharge; Confirmation Date: 3/1/2026; Horse Status: Recovering; Vaccination Status: Unvaccinated;

Number Confirmed: 1; 
Number Exposed: 11; 
Facility Type: Private Facility; 

Horse 1: 
Age: 5; Gender: Gelding; Breed: Standardbred; Usage: Pleasure Riding; Clinical Signs: Neurologic, ataxic; Confirmation Date: 2/25/2026; Horse Status: Recovering; Vaccination Status: Unvaccinated;

Number Confirmed: 1; 
Number Suspected: Unknown; 
Number Exposed: Unknown; 
Comments: On February 26, 2026, positive equine infectious anemia (EIA) results were confirmed by the Canadian Food Inspection Agency’s (CFIA) national reference laboratory for a horse located on a premises in the Municipal District of Bonnyville, Alberta. The horse participates in rodeo activities and had been tested by an accredited veterinarian at the owner’s request to fulfill a U.S. export requirement. No clinical signs of the disease were noted at the time of sampling. A CFIA investigation is underway and as per program policy, movement controls have been placed on the infected horse and any on-premises contact animals. Initial reports indicate there are several other equines on the affected premises. Movement controls will remain until all disease response activities have been completed, including follow-up testing and ordering the destruction of confirmed cases. Trace-out activities may require the CFIA to undertake actions at additional premises as outlined in the current policy. Improved biosecurity protocols have been strongly recommended to the owners to help control the ongoing spread of EIA and protect our national herd.;