Two horses in Ontario were recently confirmed positive for strangles. The horses live in the city of Hamilton and Grey County.
In Hamilton, a 10-year-old Warmblood gelding was confirmed positive on January 25 after developing clinical signs on January 23, including two draining abscesses on his head. The horse had arrived on the property two weeks prior. Six additional horses are exposed, and the horses are being quarantined.
In Grey County, a 2-year-old filly was confirmed positive for strangles on January 26 after developing clinical signs on January 25, including fever, purulent nasal discharge and enlarged submandibular lymph nodes. Eight other horses in the barn are recovering from similar clinical signs. The farm has implemented movement restrictions.
EDCC Health Watch is an Equine Network marketing program that utilizes information from the Equine Disease Communication Center (EDCC) to create and disseminate verified equine disease reports. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.
About strangles
Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t showing clinical signs can harbor and spread the bacteria, and recovered horses remain contagious for at least six weeks, with the potential to cause outbreaks long-term.
Infected horses can exhibit a variety of clinical signs:
- Fever
- Swollen and/or abscessed lymph nodes
- Nasal discharge
- Coughing or wheezing
- Muscle swelling
- Difficulty swallowing
Veterinarians diagnose horses using polymerase chain reaction (PCR) testing with either a nasal swab, wash or an abscess sample, and they treat most cases based on clinical signs, implementing antibiotics for severe cases. Overuse of antibiotics can prevent an infected horse from developing immunity. Most horses make a full recovery in three to four weeks.
A vaccine is available but not always effective. Biosecurity measures of quarantining new horses at a facility and maintaining high standards of hygiene and disinfecting surfaces can help lower the risk of outbreak or contain one when it occurs.
