EHV-1 in Penn., Possible Iowa Cases

While Ohio veterinarians are busy fighting what seems to be an especially aggressive strain of equine herpesvirus type 1 (EHV-1), two horses were euthanized due to illness from the virus at Penn National Race Course in Grantville, Penn., in an outbreak that appears to be a more typical, sporadic episode. Additionally, at least two Iowa horses have been euthanized after battling what officials believe might be EHV-1.

The two horses at Penn National were euthanized because of severe neurologic signs consistent with EHV-1. Three horses stabled with these animals tested positive for EHV-1, although reportedly, they only exhibited respiratory illness. The training barn is under a self-imposed quarantine, with disinfection protocol in place.

The Philadelphia Park Racetrack, which typically has horses shuttling between Penn National and its facility on a daily basis, placed a restriction on horses shipping in from Penn National (scheduled to end March 19). Racetracks in neighboring West Virginia have also decided to implement the shipping restriction as a precaution.

Nan Henshaw-Roberts, DVM, a veterinarian at the Pennsylvania Department of Agriculture, said, "Every so often we see EHV-1. We had one small outbreak in Pennsylvania last year, so there are isolated incidents of this."

According to Iowa State Veterinarian John Schiltz, DVM, officials know of only one premise possibly affected by EHV-1, where the two horses which were euthanized had lived. "Some of the preliminary tests have come back negative, but the definitive testing was not completed at press time. I'm hearing lots of rumors about other possible cases," he said.

"There are elements of the case in Iowa that could be considered (consistent) with equine herpesvirus," he said, and others that aren't consistent with the disease. "None of the animals have exhibited any respiratory symptoms," he explained; these signs are often seen before signs of neurological illness appear. He emphasized that EHV-1 hasn't been ruled out since similar neurologic signs were associated with the recent Findlay, Ohio, outbreak.

Both Iowa horses were submitted for necropsy to Iowa State University's diagnostic lab. Schiltz said that additional samples have been sent to the Ohio Department of Agriculture's Animal Disease Diagnostic Laboratory, where EHV diagnostics were performed recently for the Ohio EHV-1 outbreak at the University of Findlay. Confirmatory test results were to be available March 5.

In the meantime, Schiltz would like to follow up on some of the rumors that clinical signs consistent with the neurologic form of EHV-1 have affected other horses in the state.

"We're still in the process of trying to run down some of these rumors and find out what, if any, truth there was, and if there were any additional horses," he said. He is asking people to report possible Iowa cases to the state veterinarian's office at 515/281-5305.

About the Author

Stephanie L. Church, Editor-in-Chief

Stephanie L. Church, Editor-in-Chief, received a B.A. in Journalism and Equestrian Studies from Averett College in Danville, Virginia. A Pony Club and 4-H graduate, her background is in eventing, and she is schooling her recently retired Thoroughbred racehorse, Happy, toward a career in that discipline. She also enjoys traveling, photography, cycling, and cooking in her free time.

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