Disease Alerts

Number Confirmed: 1; 
Number Exposed: Unknown; 
Comments: Unvaccinated horse (laboratory confirmed 8/11/2026);

Number Confirmed: 1; 
Number Exposed: Unknown; 
Facility Type: Private Facility; 
Comments: Horse was 2 yrs old and unvaccinated;

Number Confirmed: 1; 
Number Exposed: 15; 
Facility Type: Farm; 

Horse 1: 
Age: 6; Gender: Gelding; Breed: Standardbred; Usage: Carriage; Onset of Clinical Signs: 8/3/2026; Clinical Signs: Lethargy, ataxia worse in hind limbs than forelimbs.; Horse Status: Affected And Alive; Vaccination Status: Unvaccinated;

Number Confirmed: 1; 
Number Suspected: 1; 
Number Exposed: 4; 

Horse 1: 
Age: 23; Gender: Gelding; Breed: Paint; Clinical Signs: Nasal discharge, cough; Confirmation Date: 8/11/2026; Horse Status: Affected And Alive; Vaccination Status: Unvaccinated;

Comments: Affected horses were acquired from auction;

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

Horse 1: 
Age: 16; Gender: Mare; Breed: Quarter Horse (QH); Usage: Ranch Horse; Onset of Clinical Signs: 8/8/2026; Clinical Signs: 8/8/26: ataxia and no muscle fasciculations 8/12/26: down and euthanized; Confirmation Date: 8/12/2026; Horse Status: Euthanized; Vaccination Status: Unvaccinated;

Number Confirmed: 1; 
Number Exposed: 9; 
Facility Type: Private Facility; 

Horse 1: 
Age: Yearling; Gender: Filly; Breed: Quarter Horse (QH); Usage: Breeding; Onset of Clinical Signs: 8/9/2026; Clinical Signs: 8/9/26: severe colic signs (down and rolling) 8/10/26: 3/4 ataxia on all 4 limbs 8/12/26: recovering; Confirmation Date: 8/13/2026; Horse Status: Recovering; Vaccination Status: Undervaccinated;

Comments: Vaccinated and boostered 1 m later, but not this spring.;

Number Confirmed: 1; 
Number Exposed: Unknown; 

Horse 1: 
Age: 5; Gender: Gelding; Breed: Paint; Clinical Signs: Nasal discharge; Horse Status: Affected And Alive; Vaccination Status: Undervaccinated;

Comments: Horse came from a dealer/kill pen rescue in southern Wisconsin;

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

Comments: Since the last VSV situation report (8/10/2026), 1 new confirmed VSV-positive equine premises has been identified in La Plata County, Colorado. All confirmed cases in the 2025-26 outbreak have been vesicular stomatitis New Jersey virus (VSNJV) serotype. 

Updates are as follows: Colorado • La Plata County – 1 new confirmed positive equine premises • Since the last situation report (8/10/2026), 2 previously VSV-affected equine premises have been released from quarantine in Montrose County. 

New Mexico • No new VSV-affected premises have been quarantined. 

Since the start of the outbreak, 40 VSV-affected premises have been identified (30 confirmed positive, 10 presumptive positive) in 3 states, Arizona, Colorado, and New Mexico. All 40 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), 9 premises located in 4 Colorado counties (Archuleta, La Plata, Montezuma, and Montrose Counties), and 16 premises located in 4 New Mexico counties (Rio Arriba, Sandoval, Santa Fe, and Valencia Counties).;

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;