Outbreaks | Equine Disease Communication Center

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.

Disease

Outbreak States

Start Date

End Date

Search by Alert ID

Search by Outbreak ID

1 Week

2 Weeks

1 Month

2 Months

3 Months

3+ Months

No Results

The color range is based off of the selected End Date. If the End Date doesn't have a value it will use Today's Date.

West Nile Virus

San Luis Obispo County, CA

Outbreak Identifier: 7472

Alert ID: 5039

June 16, 2026

Confirmed Case(s) - No Quarantine

Source: California Department of Food and Agriculture

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.;

Search for County

Disease Alerts