Colorado Department of Agriculture reports 37 cases of horses exposed to Equine Infectious Anemia
An incident of Equine Infectious Anemia in Weld County, Colo., has made the job of area large animal practitioners more challenging, as the state veterinarian’s office reaches out to owners whose horses may have been in contact with the one initially infected that entered the state without a negative EIA test on July 18, 2018.
As of Sept. 7, the Colorado Department of Agriculture reported that 240 animals had been on the quarantined premises during the same time as the index positive animal.
“Approximately 100 of these horses were sent to 20 other states across the country and steps are being taken to locate, quarantine, and re-test those horses,” according to a CDA press release. “At this time, no other horses have tested positive for EIA.”
The infected horse has since been euthanized, however, the index premises is under a quarantine order, as well as two associated premises that are under hold orders.
Fifteen additional premises are under hold orders in nine Colorado counties: Adams, Arapahoe, Crowley, Delta, Douglas, El Paso, Mesa, Montrose and Weld.
According to Keith Roehr, DVM, Colorado state veterinarian, the names and locations of the premises and owners are protected by the Livestock Security Act. This protects livestock information related to ownership and movement used in investigations and other official use.
Roehr said his office has been in contact with brand inspectors and state veterinarians in 20 t states in an attempt to gather information, share test results and track exposed horses. Quarantine and hold orders are being actively monitored to ensure compliance for premises with exposed horses. The Department of Agriculture has legal authority to pursue civil fines against those who violate a quarantine, hold orders or animal health requirement rules.
“Part of the difficulty is that initially, the brand inspection shows a change of ownership that goes to a person but many of the horses in the rescue network move locations and subsequently are cared for by different people so our information changes rapidly so it’s not a simple process in finding those horses,” Roehr said.
HORSE TO HORSE
Lora Bledsoe, DVM, said EIA, a virus, is transmitted horse to horse by biting insects or misuse of a needle and syringe. It is more prevalent in southern and eastern states than Colorado. Unfortunately, she said, the initial infected horse had crossed several state lines and been in contact with a number of other horses.
In an infected horse, all of the body fluid can potentially be a source of contamination, but most documented cases show contamination as a result of biting insects. One of the factors making the job of controlling an outbreak difficult, is the virus’ 60-day incubation period. An infected horse, Bledsoe said, can be infected without demonstrating symptoms during this period, making the job of determining a horse’s travel history during that time all the more important.
“Another point of concern in this particular situation is finding this horse in the height of the biting insect season as we try to prevent it from spreading,” she said.
According to Bledsoe, the infected horse entered Colorado without a negative Coggins test and was housed in Weld County. A negative Coggins test, a requirement for health papers to enter the state, is simple and rush results can be obtained the next day.
“Although laws are on the books requiring health papers to cross state lines and a negative Coggins test, in this case, individuals chose not to follow the laws,” she said. “It’s difficult for the state veterinarian to chase down how many animals may be affected.”
With no vaccination protocol and no treatment, Bledsoe said practitioners and horse owners have been managing the virus through negative Coggins testing. Infected animals must be permanently quarantined or euthanized. Symptoms, which may or may not be demonstrated, may include lethargy, anemia, petechia, or red spots on the mucous membranes, and fever.
“If the animal has been exposed, they’re going to have to be quarantined for 60 days or stop movement, or stay on their premises for 60 days, then be retested,” she said. “It’s always a good idea to have a Coggins test run on your horses once per year, especially if they travel on and off your premises or interact with other people’s horses.”
As part of the ongoing investigation and tracing of horses from the quarantined facility, the CDA is requesting assistance in supplementing contact information. If you purchased horses from that facility between July 18 and Aug. 20, 2018, you are asked to contact the State Veterinarian’s office at the CDA at (303) 869-9130. ❖