As of June 16, total confirmed cases in the outbreak were:
- Arizona — 2 EHV-1 and 1 EHM from direct exposure, 10 EHV-1 and 1 EHM from secondary/tertiary exposure;
- California — 9 EHV-1 and 7 EHM from direct exposure, 5 EHV-1 and 1 EHM from secondary/tertiary exposure;
- Colorado — 9 EHV-1 and 6 EHM from direct exposure, 1 EHV-1 from secondary/tertiary exposure;
- Idaho — 1 EHV-1 and 2 EHM from direct exposure, 3 EHV-1 and 2 EHM from secondary/tertiary exposure;
- Montana — 1 EHV-1 from direct exposure;
- Nevada — 1 EHV-1 from direct exposure, 2 EHM from secondary/tertiary exposure;
- New Mexico — 2 EHV-1 and 1 EHM from direct exposure, 1 EHM from secondary/tertiary exposure;
- Oklahoma — 1 EHM from direct exposure;
- Oregon — 2 EHV-1 and 1 EHM from direct exposure, 2 EHM from secondary/tertiary exposure;
- Utah — 1 EHV-1 and 4 EHM from direct exposure, 3 EHV-1 from secondary/tertiary exposure;
- Washington — 1 EHV-1 and 3 EHM from direct exposure; 5 EHV-1 from secondary/tertiary exposure.
Ten horses with confirmed cases of EHV-1/EHM through direct exposure died or were euthanized, plus another three horses with
confirmed cases contracted through secondary exposure.
More than 240 horse facilities were exposed across the Western states, with 62 reporting suspect or confirmed cases and 180
with no suspect or confirmed cases, says APHIS.
If the outbreak made it into the general horse population, things could have been a lot worse, Black says. The late-breaking
primary case in Montana, reported June 11 after more than a week with no new primary cases reported, is a little strange,
he says, since the incubation period for infection should have passed. But the horse could have been exposed after event,
through equipment that had been taken to Ogden. Or, since the horse showed no clinical signs of EHV-1, it could have just
been a late diagnosis, he says.
Black says he has heard some criticisms that the outbreak response was blown out of proportion, but he thinks that is a matter
"If you were in an area where you were actually seeing cases, you could relate to everything that was being done. I've heard
comments it was overplayed, but I think with the mobility of our horse industry and the fact that this is the first time we've
ever had an outbreak disseminating from a professional event, the majority felt that although we acted quite aggressively,
it was necessary to do that."
The outbreak is fading out now, though there probably will be some additional cases. Random infections are common each year,
and during the Ogden outbreak, two unrelated EHV-1 cases—one in Texas and one in Florida—were confirmed.
"I feel like that the fact that we're not seeing high numbers of secondary or tertiary cases is a good sign," Black says.
Still, it's difficult to decide when to resume normal activity.
"It's hard to know when to start back up again," he says, adding the cutting horse industry has given the green light to resume
shows, but owners are being advised to take heed of biosecurity measures. Show producers have also been advised to adopt a
"no fever" protocol to help keep the virus at bay.