A recent case of strangles has been reported at a farm in Flathead County, Montana. The attending veterinarian confirmed that one horse has tested positive for the infection, while two other horses have been exposed. As a precautionary measure, all horses are currently under voluntary quarantine.
EDCC Health Watch is a program by Equine Network that uses information from the Equine Disease Communication Center (EDCC) to produce and share verified equine disease updates. The EDCC is a nonprofit organization supported by industry donations to provide accessible infectious disease information.
About Strangles
Strangles is a contagious infection in horses caused by Streptococcus equi subspecies equi. It spreads through direct contact with infected horses or contaminated surfaces. Even horses without symptoms can carry and transmit the bacteria, and recovered horses can remain contagious for up to six weeks, potentially leading to long-term outbreaks.
Common clinical signs of strangles in horses include:
- Fever
- Swollen or abscessed lymph nodes
- Nasal discharge
- Coughing or wheezing
- Muscle swelling
- Difficulty swallowing
Veterinarians typically diagnose strangles using polymerase chain reaction (PCR) testing with samples from nasal swabs, washes, or abscesses. Treatment is based on clinical signs, with antibiotics prescribed for severe cases. Overusing antibiotics can hinder the horse’s ability to develop immunity. Most horses recover fully within three to four weeks.
Although a vaccine is available, its effectiveness varies. Implementing biosecurity measures such as quarantining new horses and maintaining high levels of hygiene and disinfection can help reduce the risk of an outbreak or contain one if it occurs.