Disease Alerts

Number Confirmed: 1; 
Facility Type: Private Facility; 
Comments: 23 yr old Horse under vet care.;

Number Confirmed: 1; 
Number Exposed: Unknown; 

Horse 1: 
Age: 12; Gender: Gelding; Breed: Quarter Horse (QH); Onset of Clinical Signs: 5/30/2026; Clinical Signs: ataxic, dragging RF foot, mild craniofacial deficits; Confirmation Date: 6/5/2026; Horse Status: Affected And Alive; Vaccination Status: Status Unknown;

Comments: The first (1st) equine case of West Nile Virus in California in 2026 was confirmed in San Luis Obispo County. On June 5, 2026, a 12-year-old Quarter Horse in San Luis Obispo County with unknown vaccine history displaying neurologic signs was confirmed positive for West Nile Virus. The gelding is alive and recovering.;

Comments: Since the last VSV situation report (6/10/2026), four (4) new VSV-affected equine premises have been confirmed positive in Valencia County, New Mexico (New Affected County). All confirmed cases in the 2025-26 outbreak have been vesicular stomatitis New Jersey virus (VSNJV) serotype. Updates are as follows: Arizona • The last VSV-quarantined premises in Arizona was released on 4/20/2026 and no new cases have been identified to date. Colorado • No new VSV-affected premises have been identified. New Mexico • Valencia County (New Affected County) – 4 new confirmed VSV-positive equine premises have been identified. Since the start of the outbreak, 23 VSV-affected premises have been identified (22 confirmed positive, 1 presumptive positive) in 3 states, Arizona, Colorado, and New Mexico. All 23 premises have had only equine species clinically affected with 15 premises located in 6 Arizona counties (Cochise, Gila, Maricopa, Pinal, Santa Cruz, and Yavapai Counties), 1 premises located in 1 Colorado county (Montezuma County), and 7 premises located in 3 New Mexico counties (Sandoval, Santa Fe, and Valencia Counties). There were other susceptible species also present on VSV premises in Arizona (cattle on 5 premises, goats on 2 premises) in Cochise, Gila, Maricopa, Santa Cruz, and Yavapai Counties, and in New Mexico (goats on 2 premises) in Sandoval and Valencia Counties, but they were not clinically affected.;

For more information, go to https://www.aphis.usda.gov/sites/default/files/vsv-sitrep-6-12-26.pdf

Number Confirmed: 2; 
Number Exposed: Unknown;

Number Confirmed: 2; 
Number Suspected: 1; 
Number Exposed: Unknown; 
Facility Type: Private Facility; 
Comments: Under veterinary care.;

Comments: Since the last VSV situation report (5/26/2026), one new VSV-affected equine premises has been confirmed positive in Santa Fe County, New Mexico (New Affected County). All confirmed cases in the 2025-26 outbreak have been vesicular stomatitis New Jersey virus (VSNJV) serotype. Updates are as follows: Arizona • The last VSV-quarantined premises in Arizona was released on 4/20/2026 and no new cases have been identified to date. Colorado • No new VSV-affected premises have been identified. Since the last situation report (5/26/2026), 1 previously VSV-affected premises was released from quarantine in Montezuma County, New Mexico • Santa Fe County (New Affected County) – 1 new confirmed VSV-positive equine premises has been identified. • Since the last situation report (5/26/2026), 2 previously VSV-affected equine premises have been released from quarantine in Sandoval County (1 confirmed positive and 1 presumptive positive premises). Since the start of the outbreak, 19 VSV-affected premises have been identified (18 confirmed positive, 1 presumptive positive) in 3 states, Arizona, Colorado, and New Mexico. All 19 premises have had only equine species clinically affected with 15 premises located in 6 Arizona counties (Cochise, Gila, Maricopa, Pinal, Santa Cruz, and Yavapai Counties), 1 premises located in 1 Colorado county (Montezuma County), and 3 premises located in 2 New Mexico counties (Sandoval and Santa Fe Counties). There were other susceptible species also present on VSV premises in Arizona (cattle on 5 premises, goats on 2 premises) in Cochise, Gila, Maricopa, Santa Cruz, and Yavapai Counties, but they were not clinically affected.;

For more information, go to https://www.aphis.usda.gov/sites/default/files/vsv-sitrep-6-10-26.pdf

Number Confirmed: 1; 
Facility Type: Private Facility; 
Comments: Recovering under vet care and owner quarantine;

Number Confirmed: 1; 
Number Euthanized: 1; 

Horse 1: 
Age: 20; Gender: Gelding; Breed: Grade; Onset of Clinical Signs: 6/1/2026; Clinical Signs: Fever, urine dribbling; Confirmation Date: 6/5/2026; Horse Status: Euthanized; Vaccination Status: Status Unknown;

Comments: Horse came from a local dealer/kill pen rescue. No other horses on site. Euthanized in part due to presumed chronic neurologic condition.;

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

Horse 1: 
Age: 9; Gender: Mare; Breed: Quarter Horse (QH); Usage: Barrel Racing; Onset of Clinical Signs: 6/3/2026; Clinical Signs: high fever, dry cough; Confirmation Date: 6/5/2026; Horse Status: Recovering; Vaccination Status: Unvaccinated;