State authorities in the US are wrestling with two outbreaks of Equine Herpes Virus-1 (EHV-1) but the risk of a widespread outbreak appear to be low.
Quarantines are in place in Utah and in Florida over the unrelated outbreaks..
The Utah state veterinarian, Dr Bruce King, has issued several quarantines in Cache County following the confirmation of two cases of the neurological form of EHV-1 along with three other suspected cases.
Symptoms of the neurological form include fever, decreased coordination, nasal discharge, urine dribbling, loss of tail tone, hind limb weakness, leaning against a wall or fence to maintain balance, lethargy, and the inability to rise.
While there is no cure, the symptoms of the disease may be treatable.
On Wednesday (US time), tests on two of three horses that were under observation returned positive results for the disease, bringing the number of confirmed cases to four. One other horse is suspected of having the disease and test results are awaited.
Utah’s Department of Agriculture and Food and the state veterinarian are not restricting any horse shows or events as a result of the cases.
King’s office believes the outbreak is confined to Cache County, but horse owners throughout Utah are advised to take extra biosecurity precautions when taking their animals to shows or public arenas.
Two of the five horses were humanely euthanized because of their condition.
The three other animals are under quarantine at their private locations, and are being observed.
The Cache County Fairgrounds horse arena has closed its riding arena until further notice as it is believed that most of the horses had been at the facility within the past week.
No other horses in Utah have shown signs of EHV-1.
King advised Utah horse owners to take extra security measures to prevent unnecessary contact with possibly infected horses, and to quickly report symptoms to their veterinarian.
Horse event coordinators should contact their show veterinarian for recommendations concerning planned events.
“As a precaution to Utah horse owners, I advise they take extra biosecurity steps to safeguard the health of their animals,” King said. “Don’t let your horses touch other horses, especially nose to nose. Isolate horses that return to the farm from a show or event.”
In Florida, a horse participating in the Horse Shows in the Sun (HITS) horse show in Ocala was referred to the University of Florida, College of Veterinary Medicine after showing clinical neurological signs on February 20.
The horse subsequently tested positive to a wild-type strain of EHV-1.
The horse is in a stable condition and is being treated at the University of Florida. There are no additional suspected or confirmed cases to date.
Florida’s Division of Animal Industry is continuing the disease investigation, which includes the HITS show grounds in Ocala, the local index farm and multiple premises that have horses that may have been exposed to the positive horse.
There are now nine premises under state quarantine: HITS Showground’s, Tent 7; Up Country Farm/Synergy Farm, Ocala; Montera Farm, Ocala; Flutterby Farm, Ocala; Foxwood Farms, Pinellas Park; Black Forest Farm, St Augustine;
Littlewood Farm, Wellington; Brookmore Farm, Oviedo; and Kings Ridge Farm, Reddick.
The quarantines do not necessarily encompass the entire premises, the agriculture department said.
Additional movement requirements or restrictions have not been imposed by Florida or any other states at this time.
The department advised horse owners and trainers to contact the venue of destination for any additional requirements prior to travel.
The equine programs manager for the Florida state veterinarian’s office, Rusty Ford, moved to dispel what he described as rumors and misinformation around the case.
“In summary, the investigative information provides there has been a single horse at the Ocala HITS Show found to be ataxic and that diagnostic testing did detect Equine Herpes Virus – Type 1.
“The testing further provided that the DNA detected represents the wild strain of EHV-1, not the mutated strain commonly referred to as neurologic pathogenic strain.
“There have been no other horses observed demonstrating similar symptoms or other illness.
“Based on the conversation I have had with the Florida Department of Agriculture, I understand about 40 horses stabled in the same barn (tent) as this index case were evaluated and their potential exposure assessed during the day on Friday by FL Veterinary Officials.
“Temporary movement restrictions of these 40 or so horses have been imposed and implemented by the Florida Department of Agriculture.”
Ford continued: “The information available at this point supports this horse to most likely be the index case and our opinion is other horses on the grounds (not housed in the tent barn with this horse) would be described as having limited opportunity of exposure. All horses on the grounds are being monitored for any evidence of illness.”