This article was updated at 4:30 p.m. on April 1 to reflect additional information obtained by The Horse.

The Maryland Department of Agriculture (MDA) reported March 31 that a horse from Pennsylvania that attended a Maryland horse show on March 15 has tested positive for the equine herpesvirus (EHV).

On April 1, the Pennsylvania Department of Agriculture told  The Horse  that "a quarantine was placed on a farm in the Dover area of York County. The quarantine will be effective for a minimum of 21 days as long as there are no further developments."

The MDA’s statement indicated that none of the other horses that attended the Maryland show and none of the horses that live with the sick horse in Pennsylvania are currently exhibiting any signs of illness. The MDA received a report of a horse that with a fever, but that animal tested negative for EHV on March 29