Recently, there have been multiple confirmed cases of strangles in Minnesota. Strangles is a highly contagious bacterial infection of the upper airway in horses.
Early signs of strangles include:
- Fever, temperature above 102 F.
- Nasal discharge which starts clear and becomes thick and yellow.
A few days after onset, horses will develop painful swelling of the lymph nodes. This swelling produces abscesses that will rupture and discharge pus. More serious cases arise when horses have lymph node swelling in the throatlatch area. These horses often refuse to eat due to pain. They may stand with their head and nose stretched out to help them breathe. Horses that are struggling to breathe need immediate veterinary care.
Some horses carry strangles but don’t show symptoms. This is likely the most important cause of recurring infection on some farms. Veterinarians take several swabs to identify horses that are carring strangles.
Veterinarians usually recommend applying hot packs to the lower jaw. This will help the abscesses mature so they can be safely opened. Once opened, a veterinarian will flush the inside of the abscess with dilute povidone-iodine solutions until they heal. Horses usually recover fully after the abscesses open.
Many veterinarians refrain from using antibiotics for uncomplicated cases. Antibiotics can delay the abscesses from maturing. Horses that have trouble breathing need a more aggressive treatment. They’ll likely need anti-inflammatories and antibiotics. The horse may need hospital care to keep their airway open and keep them hydrated.
Strangles can spread through:
- Horse-to-horse contact
- Contact with contaminated people, tack, drinking troughs, etc.
If strangles occurs:
- Isolate all the horses with symptoms to one area.
- Use separate tools and grooming equipment in the isolation area.
- Completely clean all feed, manure and bedding from contaminated areas. Keep these materials away from healthy horses.
- Thoroughly disinfect equipment, stables, fences, trailers, etc.
- Change your clothes and wash your hands before coming in contact with healthy horses.
Ideally, isolate new horses for two to three weeks. Check their temperatures regularly and watch for any signs of strangles. If signs occur, have a veterinarian take a swab and test for strangles. Horses that haven’t been exposed to the bacteria in recent years are more prone to strangles. Intramuscular and intranasal vaccines are available for horses and while these vaccines decrease the severity of strangles symptoms, they don’t completely prevent the disease.