The New York Racing Association, The Maryland Jockey Club, and Charles Town Race Track on Friday morning placed a ban on horses shipping in from Parx Racing after a horse stabled there became ill earlier this week.

Aqueduct scratched horses on their Friday card trained by Parx-based horsemen Carlos Guerrero, Michael Moore, Uriah St. Lewis, and Harold Wyner. Laurel scratched a horse trained by Joseph Taylor.

As of Friday morning, Penn National Race Course had not placed any restrictions on horses shipping to or from Parx, according to Eric Johnston, the track's director of racing.

A horse in Barn 27 at Parx trained by Ramon Martin came down with a fever on Tuesday and was sent to the Mid-Atlantic Equine Center in Ringoes, N.J.

According to David Osojnak, the director of racing at Parx, a temporary quarantine was placed on Martin's barn and the starting gate early Friday but was soon lifted. Horses are currently free to ship in and out of Parx.

Osojnak said the quarantine was placed "using an abundance of caution" and that he was waiting for an update on the situation from the Pennsylvania Department of Agriculture.

Rodney Belgrave, the director of internal medicine at the Mid-Atlantic Equine Center, said the horse was tested with a nasal swab and was determined to have the non-neurological strain of the equine herpesvirus.

"The horse is clinically doing well and is being kept in our state of the art isolation facility," Belgrave said. "The horse is not to this point neurological."

Belgrave said his team would probably wait "at least a week" and then retest the horse. Belgrave said in his experience maybe 30 percent of the horse population carry the virus but are in good health.

"It's a very complicated virus," he said.

There was some confusion Friday morning regarding whether a quarantine had been put into effect at Parx.

At 9:51 a.m., Jason Klouser, the director of enforcement for the Pennsylvania Department of Agriculture, sent out the following email to track officials:

"This morning the Executive Office was informed that a horse at Parx Racing tested for EVH-1 and a quarantine was established preventing horses from entering and exiting the facility.

"This email is to confirm that there is NO QUARANTINE AT PARX and NO HORSE TESTED POSITIVE FOR EHV-1. The Bureau of Animal Health NEVER PLACED ANY QUARANTINE nor did the Bureau Director.  It is business as usual. "

Sal Sinatra, vice president of the Maryland Jockey Club, who previously headed the Parx racing office, said typically the state will only place a quarantine at a track if a horse tests positive for the neurological strain of the herpesvirus. If a horse tests positive for the non-neurological strain of the disease, it is up to the track to determine what safety precautions should be put into place.

"We are always very cautious in these matters," Sinatra said of the Maryland Jockey Club's ban on Parx horses.

The equineherpesvirus is contagious, can cause respiratory and neurological problems in horses, and can sometimes be fatal.

There have been almost annual outbreaks of the equine herpesvirus in recent years during the winter in the Mid-Atlantic region. Last winter there were two EHV-1 quarantines at Belmont Park and one at Laurel Park.

Parx has had EHV-1 quarantines in 2013, 2014, and 2016. Four horses died from the illness during the 2016 outbreak.