GRAND RAPIDS, Mich. (WOOD) — Since the start of the new year, the Michigan Department of Agriculture and Rural Development has confirmed 12 separate outbreaks of strangles, a highly contagious equine bacterial infection.
Of the 12 outbreaks, five were in West Michigan: two in Van Buren County and one each in Montcalm, Ottawa and St. Joseph counties.
The Ottawa County case was confirmed in late January. One 22-year-old gelding was confirmed to have an infection and was last reported to be recovering. The most recent outbreak in West Michigan was reported on Feb. 17 out of Van Buren County. A 22-year-old mare was confirmed to have strangles and four other horses were suspected of contracting an infection.
Dr. Nora Wineland, the state veterinarian and director of MDARD’s Animal Industry Division, called strangles a “low mortality, high morbidity” infection, meaning it is extremely contagious and it can be deadly, but the death rate is low.
Strangles is a bacterial disease that can spread through direct or indirect contact from horse to horse. The germs are spread through saliva and other body fluids and can survive for a certain time on hard surfaces, like trailers, equipment, tack and clothes.
MDARD recommends avoiding shared equipment, isolating new horses or horses returning an event for up to two weeks and regularly using disinfectant on equipment.
An infection typically causes fevers, nasal discharge and throat inflammation. Some infections also cause abscesses in the lymph nodes and upper respiratory tract, making it difficult for the horse to breathe and swallow. Some horses can defeat the infections on their own. Others may require antibiotics.
A vaccine for strangles is widely available but, as with all vaccines, it doesn’t fully guarantee immunity. Studies do show that infection rates and infection severity are much lower with the vaccine.
According to the Equine Disease Communication Center, seven of the 12 outbreaks involved unvaccinated horses. The vaccination status in the other five outbreaks is unknown.
Because it is so contagious, the state made strangles a “monitored disease” in 2018, meaning any cases must be reported to the state within seven days of being discovered.
“We share that (information) with the Equine Disease Communication Center so that they can help spread the word out so that veterinarians and horse owners know where we’re seeing the disease, because it is highly contagious,” Wineland told News 8. “It was really on requests from the equine community. They want to know where this disease is so that they can be extra vigilant when they’re in those areas.”
Wineland suspects the case number is even higher.
“There are cases of this disease that are probably out there undiscovered,” she said. “If the horse just has a fever and clears the infection fairly rapidly, the owner or caretakers may not notice. There may not be any effort to culture, which is how we know that the disease is there.”
Wineland says the key to protecting your horses is to pay close attention and establish a good relationship with your vet.
“If they get fevers, the veterinarian needs to be called to come in. There are a number of reasons why they might (get fevers) and having somebody actually examine the horse is the best thing,” she said. “Regular visits by the veterinarian to make sure that the horses are healthy is the best defense.”