EQUINE STRANGLES
Prepared by the Georgia Dept. of Agriculture

What Is Strangles?

Strangles is an easily transmitted infectious disease that is seen worldwide in Equidae. It is caused by a bacterium called Streptococcus equi. More than one strain of the disease may exist. While usually occurring in young equine, equine of any age lacking immunity from previous infection or vaccination may succumb. The disease is not communicable to humans.

What Does Strangles Look Like

Any equine with abscessed lymph nodes of the head and neck and a high fever should be considered a strangles suspect. Common clinical signs of strangles include:

• Thick yellow discharge from nostrils and eyes
• Swollen lymph nodes of the head and neck, often draining pus
• Difficulty in swallowing, often with an extended neck
• Fever up to 106°
• Depressed with no appetite
• Coughing

We should be contacted to conduct a thorough examination and provide an accurate diagnosis.

How Are Equine Infected?

Equine strangles is highly contagious and easily transmitted through bacteria found in discharges from an infected animal. Coughing will aerosol the bacteria throughout the immediate airstream. Equine may be infected by inhaling the organism or by direct contact with contaminated buckets, grooming equipment or flies. People may also spread the disease by carrying the organism on their hands or clothing after handling an affected equine. The incubation period is typically 3-12 days and the disease normally runs its course in 2-4 weeks. However, equine may shed the bacteria from 4 weeks to as long as 8 months after clinical signs resolve. Therefore, affected animals should be isolated from unexposed equine for prolonged periods. Convalescing equine can become chronic carriers. Immunity may last from 5-8 years after recovery; however, some equine may not develop immunity post-infection and are susceptible to reinfection.

Can Strangles Be Fatal?

Nearly 100% of the animals in an exposed herd may be infected, but the mortality rate of strangles is usually less than 2%. A rare and sometimes fatal sequelae is purpura hemorrhagica, which is acute and generalized hemorrhage. Death generally occurs due to nervous system infections, pneumonia, or abscesses developing in the internal organs. Strangles gets its descriptive name because swollen lymph nodes may cause airway obstruction and death due to asphyxiation.

What Are Complications Of Strangles?

Strangles may damage the heart and kidneys, and cause anemia and immune system disorders. A chronic form known as "Bastard Strangles" may occur if abscesses develop in unusual areas of the body, such as the abdomen or chest cavity. Significant danger from this form of the disease occurs when these abscesses rupture. Bastard Strangles occurs due to immune system failure or overwhelming and rapid spread of the bacteria throughout the body.

Is There A Vaccine?

Three vaccines are currently available in the US, including intranasal and injectable forms Vaccination provides the most benefit in herds in which Strangles is already present (endemic). Vaccination in other circumstances may not be as effective. Side effects from vaccination may include abscess formation at the site of the injection or a mild respiratory reaction. Contact us for vaccination recommendations.

How Is Strangles Treated?

Infected equine should be immediately isolated from other equine. A veterinarian should examine the animal and provide medical advice and treatment. Complete rest and nursing care should also be provided. Hot packs applied to abscesses may expedite healing. Affected equine should be fed soft, palatable feed if having trouble swallowing.

Can Strangles Be Prevented And Controlled?

Strangles can be prevented from spreading by taking the following precautions:

• Vaccinate equine if Strangles is endemic in the herd or on the farm.
• Isolate new equine for two to three weeks before introducing them to the herd. Check rectal temperatures twice daily for evidence of fever. Because fever usually develops two days before bacteria shedding, early detection of fever may prevent further transmission.
• Any newly isolated equine with a nasal discharge should be examined by a veterinarian. Prompt diagnosis is important to prevent additional spread.
• If an equine is infected, stop movements of equine on and off the infected premises. • Disinfect stalls, water troughs, tack, and grooming utensils. Do not mix equipment between infected equine in isolation and noninfected equine.
• Handle infected equine only after handling noninfected equine. If possible, assign one person to handle affected equine and to avoid contact with healthy equine. Wash hands, arms, footwear, etc. after handling infected animals
• Bedding associated with infected equine should be destroyed by burning with thorough disinfection of the stall. If burning is prohibited, the bedding should be composted under cover.
• Implement strict fly control measures by installing screens, electronic fly killers and using insecticides.
• The Strangles bacteria can be killed by drying and sunlight. Phenolic disinfectants are recommended in equine facilities. Bleach and quaternary ammonium compounds quickly become inactivated with organic matter, so it is important to thoroughly clean surfaces prior to disinfection.

Contact our office to set up a vacination schedule for your equine family!