One horse in Florida has tested positive for strangles, and two horses are suspected positive. In Citrus County, a 30-year-old Quarter Horse mare tested positive on January 10 after developing clinical signs on December 19, including cough, fever and lymphadenopathy. She is currently affected and alive, and 15 horses have been exposed.
In Santa Rosa County, a mare is suspected positive after developing mucopurulent nasal discharge and lymphadenopathy. The farm is under investigation by the county, and testing status is unknown. Two other horses have been exposed to the sick horse.
In Hillsborough County, a 6-year-old mare is suspected positive. She developed clinical signs, including mucopurulent nasal discharge and lymphadenopathy, on January 14. The horse is under official quarantine pending laboratory confirmation. It is unknown if other horses were exposed.
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.
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:
- 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.