PHOENIX — In California, big events are being canceled and horses are being euthanized because of an outbreak of the equine herpesvirus.
In Orange County, hundreds have been exposed and more than a dozen horses have tested positive. Donna Hyde, who runs a horse therapy nonprofit there, is working to spread the word.
"I've heard of over 50 horses dying so far, so it's pretty serious," she said. "They get symptoms of a snotty nose and the symptoms come on very quickly."
As of Thursday, no cases have been reported in Arizona. But it's a virus Brian Dygert, general manager of WestWorld of Scottsdale, is watching closely.
"Of course, we have concerns," he said. "Individually I have concerns anytime I see the case, anytime I see any case."
Dygert says more than 14,000 horses come in and out of his facility every year, 5,000 in just the last four weeks.
Before they arrive, he says every horse must have a health certificate within the past 30 days showing they have no symptoms and that they've been vaccinated. He says the show managers this weekend are requiring a 10-day certificate.
"That's going to ensure that no matter where that horse has been in the last 30-40 days, it's been seen by a veterinarian and or tested and therefore it's healthy to come here," he said.
He says WestWorld of Scottsdale also enhanced their disinfecting plan two years ago, cleaning more between events.
The shows are a huge economic driver to not just Scottsdale, but the entire state of Arizona.
"I carry the responsibility of making the decision on when to stop an event," Dygert said. "I don't want to stop an event. There's significant consequences to that including economics."
As of March 16, the state of California set new guidelines recommending all equine events be postponed until the end of the month.
Shows are continuing in Arizona and are scheduled throughout the next few months.