Michigan mare tests positive for strangles – The Horse

On June 19, a two-year-old Percheron mare in Ionia County, Michigan, was diagnosed with strangles. On June 8, the mare began showing clinical signs, including nasal discharge, and is currently under quarantine.

EDCC Health Watch is an Equine Network marketing program that uses information from the Equine Disease Communication Center (EDCC) to create and disseminate verified reports on equine diseases. EDCC is an independent, nonprofit organization supported by industry donations to provide open access to information about infectious diseases.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies even and spread through direct contact with other horses or contaminated surfaces. Horses that do not show clinical signs can harbor and spread the bacteria, and recovered horses remain infectious for at least six weeks and can cause long-term outbreaks.

Infected horses may exhibit various clinical signs:

• Fever
• Swollen and/or inflamed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• difficulties swallowing

Veterinarians diagnose horses using a polymerase chain reaction (PCR) test on a nasal swab, nasal wash, or abscess sample and treat most cases based on clinical signs. In severe cases, antibiotics are used. Overuse of antibiotics can prevent the development of immunity in an infected horse. Most horses make a full recovery within three to four weeks.

While a vaccine is available, it is not always effective. Biosecurity measures such as quarantining new horses at a facility and maintaining high standards of hygiene and disinfecting surfaces can help reduce the risk of an outbreak or contain an outbreak if it does occur.