McKee-Pownall Equine Services | Health Care FAQ

Health Care FAQ

What is Strangles?

Strangles is a highly contagious and serious infection of horses and other equids caused by the bacterium Streptococcus equi (S. equi). The disease is characterized by severe inflammation of the mucosa of the head and throat, with extensive swelling and, often, rupture of the lymph nodes that produces large amounts of thick, creamy pus.
The bacteria is highly contagious and can spread rapidly through a barn by both direct (nose to nose) contact, and indirect contact (for example infected stall equipment, water troughs, or on people’s hands or clothing).

Once a case of strangles is confirmed on a farm by way of a nasal swab, it is important to prevent the spread of the bacteria to other horses. Some recommendations include:

-No movement of horses on the property should be allowed for at least 4 weeks after the last symptom is seen.
-Horses from farms with cases of strangles on the property, or suspicious of being infected, should not be taken to or admitted into barns until they have undergone a 2-3 week quarantine period and been tested negative for S. equi.
-Infected horses and those with high exposure (eg. Pasture mates of infected horses) should be isolated and not allowed to come into contact with other horses until they are no longer shedding the bacteria – at least 4 weeks after the last symptom.
-Use separate stall cleaning supplies and personnel for the quarantined animals. Quarantine area staff should change their coveralls and boots before leaving the quarantine area and should wash their arms and hands with antibacterial soap or alcohol-based disinfectant solution.
-Any item coming into contact with an infected horse or its stall (eg. Haynets, water buckets) should be disinfected before being used for another horse.
-Contaminated pasture areas should be rested for at least 4 weeks before using them for normal turnout.

The strangles bacterium is commonly transmitted by silent carrier horses – horses that are not showing symptoms but have the bacteria in their guttural pouches. The bacteria are shed from these horses onto equipment, people or directly to other horses. Mixing of horses from different sources without a quarantine period (eg. horse shows), or the movement of people or equipment between barns, is a common source of bacteria spread.

If you have further questions or concerns, please contact McKee-Pownall, or your veterinarian, for further advice.