Strangles is a highly contagious bacterial infection of the of the head and neck caused by the bacterium, Streptococcus equi subspecies equi (S. equi equi).
Click on the picture to watch a short video about Strangles
What should I look out for?
Clinical signs can vary between individuals and signs to look out for include:
Fever, usually at least 39-40°C or 102.5-104°F (this is usually the first clinical sign to occur)
Swollen and painful lymph nodes around the head and neck leading to abscesses
Difficulty swallowing and breathing and abnormal respiratory noises
Cough
Depression and loss of appetite
A runny nose (watery to begin with, but becoming thick pus within days)There is also a form of the disease known as ‘atypical strangles’ which is when horses only show very mild clinical signs, but they are still infectious
Complications
Some cases develop serious complications:
‘Bastard strangles’ occurs when abscesses form in different areas of the body
Purpura haemorrhagica is inflammation of the blood vessels leading to swelling (oedema). This can occur under the belly, limbs and the sheath. There are often also small areas of bruising/bleeding on the mucous membranes (gums and eyes)
Transmission
Strangles is transmitted by both direct horse to horse contact and indirectly via contaminated drinking water, feed, equipment and people.
Carriers
Approximately one in 10 horses that recover from strangles become long term carriers. This is when clinical signs resolve, but some bacteria remain in the guttural pouch. These bacteria will shed periodically without any clinical signs and can infect in-contact horses.
Diagnosis
An initial diagnosis may be based on clinical signs. There are tests available to confirm if a horse is suffering from strangles and swabs or other samples can be collected to check for the bacteria.
Treatment
Treatment is aimed at keeping the horse comfortable with good nursing and supportive care and anti-inflammatory medication. Most horses will recover within three to four weeks, but more severe cases may take longer to resolve.
Prevention
New horses entering a yard should be isolated for 3-4 weeks before joining a herd. As a horse can be a silent carrier without showing any clinical signs blood tests are useful to identify these animals.
Vaccination is a useful management tool, alongside good stable management and biosecurity measures, and can play a really important role in improving herd immunity and reducing the number of strangles cases in the equine population.
Outbreak management
Click on the picture to watch a short video about the management of a Strangles outbreak
The yard/premises should be closed to prevent horse movement and horses should be split into three groups:
Red – horses showing clinical signs or those that have tested positive
Amber – horses with known contact with positive cases
Green – horses who have had no contact with positive cases
The groups should be managed separately and all equipment must be thoroughly disinfected. Any horse in the amber or green group which develops clinical signs should be moved to the red group immediately. Rectal temperatures should be taken twice daily to check for fever.
The premises should remain closed, with no horse movements, until free of disease. For further information contact us on 01834 860871. We are here to help.