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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.



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West Nile Virus
Tehama County, CA
Outbreak Identifier: 5376
Alert ID: 2758
October 06, 2022
Confirmed Case(s) - No Quarantine

California Department of Food and Agriculture

Number Confirmed: 1;
Age: 3; Gender: Mare; Breed: Quarter Horse (QH); Onset of Clinical Signs: 9/28/2022;
Clinical Signs: Acute recumbency, ataxia (all 4 limbs), difficulty rising; Confirmation Date: 10/5/2022; Horse Status: Affected And Alive; Vaccination Status: Status Unknown;
Comments: On October 5, 2022, a 3-year-old Quarter Horse mare with an unknown vaccination history in Tehama County, displaying acute neurological signs, was confirmed positive for West Nile Virus. The mare is alive and recovering. This is the thirteenth case of equine WNV confirmed in California in 2022. For more information about West Nile Virus, go to: WNV Factsheet.
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