Strangles, What Is It?

Written by: Dr. Jay Altman

Strangles, a highly contagious bacterial disease caused by streptococcus equi, is very common in our area. Although rarely life threatening, it can cause severe clinical symptoms including high fever, lethargy, nasal discharge, abscessation, laryngitis and even pneumonia.

The bacterium responsible for strangles is usually contained and grows in the lymph nodes of the upper respiratory tract, which is the most common place for abcessation to occur. The outward sign of this lymph node growth is a swelling underneath the jowl or the throat, although internal abscessation in the larynx is also quite common and can cause the choking symptom which gives strangles its name. Additionally, in a certain percentage of cases, the bacteria can infiltrate or travel to other areas of the body, causing substantial complications.

Strangles most commonly affects young horses, under the age of 5 or 6 years old; and older, immune-compromised patients. We have found the intranasal vaccine to be effective in control of the disease. Our recommendations on vaccination of any single or group of horses is based upon both the animal's age and their degree of exposure or risk of exposure.