Reported Cases
Recently rumors of a strangles outbreak in Maryland have been circulating throughout social media. As your source for breaking news in the state, The Equiery reached out to our Acting State Veterinarian to get to the bottom of the  matter. Thank you to the Maryland Department of Agriculture Animal Health Program for always providing us with prompt, detailed, and informative statements for our readers. ​​

According to MDA’s acting state veterinarian Jo Chapman, DVM MPH, there has  been only one officially reported case in Maryland over the last few weeks. The confirmed case was one horse on a farm in Cecil County. That horse has now been euthanized. MDA also stated that other horses on the property had been symptomatic but tested negative for strangles as of August 2. As a best practice, the farm implemented biosecurity measures and has temporarily canceled all activities.The Equiery was also made aware of two cases of strangles in horses that were stabled at the Tryon International Equestrian Center in North Carolina during the US Pony Club Championships East competition on July 25-28. According to a Facebook post from USPC on August 12, the infected horses were stabled in Barn 3 at Tryon. USPC did not release which state(s) these horses returned to after championships ended.

Strangles Protocol in Maryland
In Maryland, strangles is not a reportable disease, meaning MDA does not have to be notified, however it is best if they are contacted so they can help with containing the spread of the disease. Although farm owners are urged to implement their own quarantine procedures, that is not mandated by MDA. Local and state veterinarians do have protocols in place to help farm owners contain the disease and prevent the spread to other horses on and off the property.

For containment and control of strangles, MDA recommends (in order of priority):

The infected horse(s) should be isolated immediately. The isolation area should prevent any direct contact with other horses. Turnout areas, water and feed troughs as well as any tack, brushes, etc must not be shared with other horses.

Streptaococcus equi is highly contagious bacteria which incubate and spread through the shedding of the bacteria from nasal discharge or from other abscesses, typically of the lymph nodes under the jowl and around the throat latch area. The bacteria can live outside of the horse for up to eight weeks, so isolation of any infected horses is immediately important.

Personnel who are treating the infected horse(s) should use disposable gloves if possible and wash/sanitize their hands thoroughly after treating the infected horse(s). It is also recommended that these personnel change their clothing and boots before leaving the isolation area.

A local veterinarian should be called to work out treatment options for the infected horse(s). Antibiotics are typically the first line of defense during the early stage of the infection. This treatment may prevent abscess formation.. Once abscesses have formed, antibiotics typically are ineffective. It is also recommended to contact regulatory agencies, and others whose horses may have been in contact with the infected horse.

Daily Monitoring
All other horses on the property should be monitored daily and immediately isolated if they start showing any systems of strangles. Early symptoms typically develop within two to six days after exposure to the bacteria. Symptoms can include:

1. Horses can seem depressed, stop eating and/or drinking and will have a clear nasal discharge.
2. Fevers can spike as high as 106 F. As the disease progresses, the lymph nodes will start to swell and can eventually develop abscesses.
3. In severe, but rare, cases, abscesses can form throughout the body, most commonly in the lungs, liver, spleen, kidney and brain.
4. It is recommended to take horses’ temperatures twice daily.

Best Practices & Self-Imposed Quarantine
It is also recommended that farm owners restrict the movement of any horses coming in or going out of the property. These restrictions should stay in place for a minimum of four weeks or until three consecutive nasopharyngeal swabs are collected. Pastures and turn out areas where the infected horses were housed should be left open for at least 30 days. During this whole process, farm owners need to clean and disinfect all water containers, feeders, brushes, stall walls, fencing, trailers, etc before returning them to general use.

Good News
Typically, horses will recover from strangles in three weeks after receiving treatment but can continue to shed the bacteria for several months.

The Equiery urges its readers to contact MDA directly if they have a case of strangles on their property and to implement quarantine procedures immediately.