Horse Scout Blogger has just seen the H&H article about Event rider Dani Evans who has told H&H she has had to shut down her yard after an outbreak of strangles was confirmed last month (27 February). What a disaster for her and her owners. My sympathies go out to them all. I hope that they are on the way to being clear of the disease now. Read more at here
There can be nothing more worrying for the horse owner nor frustrating for the professional competition rider than having a yard shut down through something like this. Most especially when every precaution has been taken through good biosecurity and hygiene and yet something like strangles or equine hereps or even ringworm sweeps through a yard.
Strangles is caused by the bacterium Streptococcus equi (Strep. equi), it is one of the most common equine respiratory infections in the world. It can affect horses of all ages and types.
Strangles is a common threat
The disease causes major economic losses to the equine industry worldwide due to its prolonged course, extended recovery period and associated serious complications. According to International Collating Centre reports, strangles is responsible for 30% of infectious disease episodes. Reliable UK statistics are not available, but in Sweden, where strangles and equine flu are notifiable diseases, there are approximately four cases of strangles for every case of flu (see table).
Reported cases in Sweden 2000 2001 2002 2003
Strangles/flu ratio 4:1 4:1 6:1 4:1
A dangerous and contagious disease
Strangles itself can kill (in simple cases there is a one percent mortality rate), but the major reason for its concern is the speed with which strangles spreads among horses, especially in a stable setting. In large horse populations, established outbreaks may last for months, essentially shutting down stabling premises.
Moreover, some “recovered” horses (carriers) can harbour Strep. equi with no outward clinical signs. Consequently, new or recurrent outbreaks are likely unless costly diagnostic procedures and aggressive quarantine measures are used.
S. equi infection can be transmitted both directly via close contact with an infected horse or indirectly through shared housing, water and feed buckets, shared tack and equipment; and contact with shared personnel such as groom, instructor, farrier, veterinary surgeon or more unexpected sources such as a pet dog.
Signs include:
• fever
• loss of appetite
• depression
• marked ‘snotty’ nasal discharge (this is the most common sign)
• lymph node swelling and abscesses predominantly of the head and neck
• Remember that not all horses will show all (or any) of these signs
If you suspect Strangles:
Isolate the horse and any other horses that have had direct, particularly nose-to-nose contact with it. Also isolate those which have/may have had indirect contact with the suspect case (such as through sharing of water and/or feed buckets, tack, handlers, and so on). Isolation should be away from other horses in the yard with which they have not had such contact. Do not allow other animals to enter the stable where the infected horse was kept or have access to its feed or water container.
Call your veterinary surgeon and discuss with the appropriate management, sampling and laboratory strategies to investigate whether infection with S. equi is the likely cause of the clinical signs. It may be beneficial to take more than one sample from more than one horse or on more than one occasion from the same horse to confirm or exclude the suspicion of strangles. Depending on the type and timing of sampling of cases, S. equi can sometimes be difficult to confirm and your vet will be able to advise you further.
Further information can be found here through the British Horse Societies very useful pdf on the Voluntary code in the event of a strangles outbreak. “Strategy to eradicate and prevent Strangles (STEPS)”
Vaccination can be used as part of a strangles management program. It can form a critical element in preventing strangles outbreaks on yards but it is not a substitute for good stable management and disease awareness.
A vaccine is now available to reduce clinical signs and the incidence of lymph node abscesses. Developed by MSD Animal Health, Europe’s leading manufacturer of equine vaccines. The vaccine is now available to help owners and veterinarians manage this disease.
The vaccine can be used in horses from just four months of age and is administered by injecting a very small volume of vaccine into the upper lip of the horse. In trials undertaken by MSD Animal Health, horses tolerated this innovative application method well.
Where vaccination is required and to minimise the risk of strangles taking hold, all horses in a yard should be vaccinated.
This vaccination information is brought to you by MSD Animal Health, manufacturers of Equilis® StrepE. Equilis® StrepE which can only be prescribed by your veterinary surgeon whose advice should be sought.
A horse’s vaccination program should be based on the risk of disease for the horse, the yard and also the economic consequences of an outbreak. In general, the more a horse is in contact with other horses the greater its risk of contracting strangles.
Discuss an appropriate vaccination schedule for your horse with your veterinary surgeon
