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.



West Nile Virus
Lexington County, SC
Outbreak Identifier: 6050
Alert ID: 3499
November 20, 2023
Confirmed Case(s) - No Quarantine

Clemson Livestock Poultry Health

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

Horse 1: 
Age: 13; Gender: Gelding; Breed: Tennessee Walking Horses; Usage: Pleasure Riding; Confirmation Date: 11/17/2023; Horse Status: Euthanized; Vaccination Status: Unvaccinated;

West Nile Virus
McIntosh County, OK
Outbreak Identifier: 6044
Alert ID: 3492
November 15, 2023
Confirmed Case(s) - No Quarantine

State Veterinarian Office

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

Horse 1: 
Age: 2; Gender: Filly; Breed: Quarter Horse (QH); Onset of Clinical Signs: 11/5/2023; Clinical Signs: muscle fasciculations, ataxia; Confirmation Date: 11/14/2023; Horse Status: Recovering; Vaccination Status: Unvaccinated;

West Nile Virus
Westchester County, NY
Outbreak Identifier: 6042
Alert ID: 3488
November 10, 2023
Confirmed Case(s) - No Quarantine

NYS Department of Agriculture and Markets, Division of Animal Industry

Number Confirmed: 1; 
Number Exposed: Unknown; 

Horse 1: 
Age: 15; Gender: Gelding; Onset of Clinical Signs: 10/28/2023; Clinical Signs: Choke, fasciculations of the head/neck/shoulders, tripping, crossing over of back feet, lethargy, quiet mentation; Horse Status: Recovering; Vaccination Status: Unvaccinated;

West Nile Virus
San Mateo County, CA
Outbreak Identifier: 6038
Alert ID: 3484
November 09, 2023
Confirmed Case(s) - No Quarantine

California Department of Food and Agriculture

Number Confirmed: 1; 

Horse 1: 
Age: 11; Gender: Mare; Breed: Warmblood (WB); Onset of Clinical Signs: 10/25/2023; Clinical Signs: ataxic (all 4 limbs), muscle fasciculations in muzzle, lethargic; Confirmation Date: 11/1/2023; Horse Status: Affected And Alive; Vaccination Status: Unvaccinated;

Comments: The thirty-first (31st) case of West Nile Virus in California in 2023 was confirmed in San Mateo County. On November 1, 2023, an 11-year-old Warmblood mare in San Mateo County displaying neurologic signs was confirmed positive for West Nile Virus. The mare is alive and recovering.;

West Nile Virus
Harper County, OK
Outbreak Identifier: 6036
Alert ID: 3482
November 07, 2023
Confirmed Case(s) - No Quarantine

State Veterinarian Office

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

Horse 1: 
Age: Yearling; Gender: Stallion; Breed: Quarter Horse (QH); Onset of Clinical Signs: 10/29/2023; Clinical Signs: Hindlimb weakness; Horse Status: Recovering; Vaccination Status: Unvaccinated;

West Nile Virus
Ottawa County, OK
Outbreak Identifier: 6032
Alert ID: 3477
November 06, 2023
Confirmed Case(s) - No Quarantine

State Veterinarian Office

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

Horse 1: 
Age: 10; Gender: Gelding; Breed: Quarter Horse (QH); Onset of Clinical Signs: 10/22/2023; Clinical Signs: Muscle fasciculations, incoordination; Confirmation Date: 11/3/2023; Horse Status: Recovering; Vaccination Status: Unvaccinated;

West Nile Virus
Centre-du-Québec, QC
Outbreak Identifier: 6030
Alert ID: 3474
November 03, 2023
Confirmed Case(s) - No Quarantine

MAPAQ

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

Horse 1: 
Age: 3; Gender: Filly; Onset of Clinical Signs: 10/24/2023; Clinical Signs: Lethargy, ataxia, facial tremors; Confirmation Date: 11/2/2023; Horse Status: Recovering; Vaccination Status: Unvaccinated;

West Nile Virus
Houston County, TX
Outbreak Identifier: 6026
Alert ID: 3470
November 03, 2023
Confirmed Case(s) - No Quarantine

Attending Veterinarian

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

West Nile Virus
Clare County, MI
Outbreak Identifier: 6024
Alert ID: 3468
November 03, 2023
Confirmed Case(s) - No Quarantine

Michigan Department of Agriculture and Rural Development

Number Confirmed: 1; 
Number Exposed: Unknown; 

Horse 1: 
Age: 14; Gender: Mare; Breed: Quarter Horse (QH); Onset of Clinical Signs: 10/23/2023; Clinical Signs: Head tremors; Confirmation Date: 11/2/2023; Horse Status: Recovering; 

Comments: Owner states they vaccinated horse in the past against disease, but date vaccinated unknown. Reportedly would have been over a year ago.;

West Nile Virus
Coal County, OK
Outbreak Identifier: 6015
Alert ID: 3458
October 30, 2023
Confirmed Case(s) - No Quarantine

State Veterinarian Office

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

Horse 1: 
Age: 5; Gender: Mare; Breed: Quarter Horse (QH); Onset of Clinical Signs: 10/23/2023; Clinical Signs: Mild ataxia, muscle fasciculations and CN deficits; Confirmation Date: 10/25/2023; Horse Status: Recovering; Vaccination Status: Status Unknown;