Clemson animal health experts confirm SC's first cases of equine infectious anemia in eight years
A fifth horse in South Carolina has been euthanized after contracting equine infectious anemia, or EIA, animal health researchers confirmed Monday.
State Veterinarian Michael Neault said all five cases of the disease have been reported since July, and that the cases are the state’s first since a lone case in a donkey in Aiken County was reported in 2014.
Dr. Neault said the infections have been traced back to a single racehorse training facility in the state, but he did not say which.
Typically, EIA infections occur following a bite from a horsefly or deerfly. However, the five cases Dr. Neault has seen in the last month likely occurred from horse vaccinations, he said.
“We’ve been finding that it’s really the sharing of needles,” Dr. Neault said. “If you’ve got a contaminated needle, you hit one animal that hadn’t been tested, and as you keep going on down the line, you’re starting to introduce that virus into all of them.”
Dr. Sean Eastman, who leads Clemson’s animal health team, said that so far, the number of EIA cases has topped off at five.
“The investigation continues and we’re still chasing down contacts and tracing horse movements,” Dr. Eastman said. “It’s five currently, but the possibility of it extending even more is there.”
Both veterinarians say they are “cautiously optimistic” that the outbreak seems to be contained.
While the disease does not affect humans, it is communicable and serious for equine animals.
According to the USDA, animals suffering from EIA could experience jaundice,
rapid breathing, rapid heart rate, swelling of limbs, bleeding from the nose, or red/purple spots on mucous membranes, and blood-stained feces
“There is no treatment for EIA, so if an infected animal does not die from the disease it will become a lifelong EIA carrier and serve as a reservoir for the disease, putting other equines at risk,” Neault said in an earlier statement on the EIA outbreak. “For this reason, they must be permanently isolated and quarantined from other animals or they must be euthanized.”
Another cause for cautious optimism from Drs. Neault and Eastman is that so far this year, there have been no reported cases of eastern equine encephalomyelitis, or EEE, which occurs mainly through mosquito bites.
“Every time we … pull blood for EIA testing, we’re also testing [animals] for other diseases,” Dr. Eastman said. “But so far, they’ve been clean for those.”
And while Dr. Eastman feels the lull in EEE is “eerily quiet” given that this is the time of year when at least a few cases show up, he said he’s hopeful that things stay calm.
“EIA is communicable to other horses and is a serious animal health threat,” Dr. Neault said in the earlier statement. “Thankfully, with other deadly diseases like EEE, West Nile virus and rabies, we have effective equine vaccinations available. So it’s a good idea for all horse owners to plan a regular Coggins test just like they do their animals’ annual vaccinations.”
But it's a bad idea to reuse needles, he added, given how inexpensive new needles are for each horse compared to the many costs that come from euthanizing an animal.
EIA is a reportable animal disease in all 50 states, meaning that positive cases must be reported by the testing laboratory to local state or federal animal health officials within two days of discovery. LPH maintains an animal reportable diseases list, available by clicking here.