The Arizona Department of Agriculture has released an update on the neurologic EHV-1 outbreak in Maricopa County. Three additional horses have been confirmed positive.
On May 16, the Arizona Department of Agriculture noted that 13 horses are still considered exposed during this outbreak. The most recent positive horses are a 12-year-old pony that had onset of clinical signs on May 10 that included lethargy. The pony was confirmed positive on May 14 and is recovering. The pony had been vaccinated.
A 20-year-old Quarter horse had onset of clinical signs on May 9 that included ataxia and muscle fasciculation. The horse was confirmed positive on May 14 and is alive. The horse was reported to be undervaccinated.
The last new case reported was a horse that showed clinical signs of ataxia on May 10 and was confirmed positive on May 14. The horse is affected and alive, and it was reported to be undervaccinated.
Information for this report was provided by the Equine Disease Communication Center.
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