By T. D. Thornton
Turf Paradise in Arizona on Feb. 12 became the fifth Thoroughbred track in the country since the start of the new year to have a quarantine imposed because of a confirmed case of equine herpesvirus type 1 (EHV-1).
But what appears to be a recent spike in outbreaks should not be mistaken for a nationwide EHV pandemic, an official with the American Association of Equine Practitioners (AAEP) cautioned.
Rather, the apparent spate of EHV reports could just be a function of the AAEP’s Equine Disease Communication Center making outbreak information more readily accessible to the media and the general public, Dr. Nathaniel A. White II, DVM, a chair of the AAEP’s National Equine Health Plan Task Force, told TDN Tuesday.
The more robust recent reporting via the EDCC’s various public-facing platforms, which began sending out real-time alerts in 2016, can make it difficult to drill down precise EHV-1 prevalence comparisons with years prior to the implementation of the alert system, White said.
“It can happen at any time of the year, but it seems like this winter or early spring we’ve seen more outbreaks than during the rest of the year,” White said. “I’m not sure we know that it’s increased, because the reporting systems [previously] were not in place to keep track of every case in the country. That’s changing with the EDCC. We’ve been able to capture that. But this is [traditionally] the season where we see the most of it.
“[EHV-1] is called ‘reportable,'” White explained. “That is, the state veterinarians, when they have a case in their state, if it’s reportable in their state they’re obligated to look at the case and try to keep it from spreading.
“But until we started the EDCC, there was no central reporting system,” White continued. “So I think that we’re able to capture more of them now and know that they’re happening, whereas before [an outbreak could occur] and [the state] would just take care of it and nobody outside that state would necessarily know.”
Since January, EHV-1 quarantines have been imposed and subsequently released at Belmont Park in New York, Laurel Park in Maryland and Portland Meadows in Oregon. A barn remains under quarantine at Turfway Park in Kentucky after a 3-year-old was euthanized following an EHV-1 diagnosis there.
Standardbred entities have also been affected. Racing at The Meadows in Pennsylvania has been shut down since late January through at least Feb. 23, and The Blooded Horse Sales Company in Ohio canceled an auction this month.
Also according to the EDCC, the University of Pennsylvania’s New Bolton Center in Pennsylvania had a state EHV-1 quarantine lifted effective Feb. 3, but a self-imposed quarantine remains in effect at that facility for three horses that previously tested positive.
The Turf Paradise quarantine is for the “wild” strain of EHV-1 and traces to a horse that presented with neurological impairment Feb. 8 and was moved to a referral hospital. One barn at the racetrack has been quarantined while the state veterinarian works with track officials to monitor for exposed horses.
“People should be aware that [contracting EHV-1] is possible, but considering the total number of horses, it’s probably not that prevalent,” White said. “But it certainly can happen, particularly when horses travel and they’re very active and stressed, and people should practice biosecurity, which is the best way to prevent their horses from getting the problem.”