A young Thoroughbred racehorse has been euthanized at Maryland's Laurel Park racetrack after showing signs and testing positive for the Equine Herpes virus (EHV). Officials curtailed horse traffic in and out of the racetrack last Friday when the sick filly was confirming to be infected with EHV.
It was just two years ago that an EHV outbreak on the South Florida showgrounds at Wellington threatened the hunter/jumper showing circuit; this is the second outbreak at a racetrack in the state of Maryland in recent years.
On Monday, Maryland Department of Agriculture (MDA) Animal Health staff took nasal swabs and blood samples from the 18 remaining untested horses in Barn 1, where the filly was tabled. Complete results received on Tuesday from the horses stabled in Barn 1 to date are all negative test results. In addition, samples from 31 lead ponies submitted by the Maryland Jockey Club on Saturday are all negative, as are tests on horses that had shipped out of the barn.
Equine herpes virus causes upper respiratory infection and can lead to severe neurological disease. There is currently no known method to reliably prevent the neurological 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 neurological form. Transmission occurs primarily by direct nose to nose contact or contaminated hands, equipment, feed and water. It can also be spread up to 35 feet by airborne droplets. This virus is not associated with any human health risk.
Photo of bio-emergency drill courtesy of Maryland Department of Agriculture Animal Health Section.