A Hold Order has been placed on Barn 1 at the central Maryland track, which means none of the horses in the barn will be permitted to train or race, pending further testing. None of the other 29 horses are showing neurologic signs.
"We are working cooperatively with all involved parties using the most up-to-date science and best practices to manage this situation and are doing comprehensive tests to determine the nature of this outbreak," said Maryland State Veterinarian Dr. Guy Hohenhaus. "In the meantime, we urge everyone's diligence in continuing strong preventive measures such as keeping new horses separate from your general barn population for at least one week, disinfecting and keeping vaccinations up to date."
Equine herpesvirus causes upper respiratory infection and can lead to severe neurological disease. Four horses died at Pimlico Race Course and Laurel Park during an outbreak of the virus in 2006.
"Today's news is disappointing but we have already put the proper precautions into place to control the situation," said Maryland Jockey Club racing secretary Georganne Hale. “We learned a great deal from 2006 and now know to shut things down immediately if there is a possible case so as to reduce the possibility of it spreading. The one advantage to having this happen in Barn 1 is that it is already isolated from much of the backside.”
There is currently no known method to reliably prevent the neurologic form of EHV-1 infection. It is recommended to maintain appropriate vaccination procedures in an attempt to reduce the incidence of the respiratory form of EHV-1 infection, which may help prevent the neurologic form. Transmission of the virus can occur via coughing or sneezing over a distance of up to 35 feet as well as by direct contact with infected horses, feed and equipment. Based on clinical signs, there is no reason to believe that there is any human health risk.