New Vaccine to Prevent Strangles

Strangles is a nasty infection that can spread quickly from horse to horse, often causing serious problems.

Strangvac is a new vaccine for horses to prevent against catching strangles, caused by the Strep equi bacteria.  Although it has been possible to vaccinate horses against strangles previously, the new vaccine offers ground-breaking new advantages which will help make vaccination a much more practical option for horse owners:

• Strangvac is up to 94% effective at preventing or reducing infection in vaccinated horses.
• The vaccine is administered by a simple injection into the muscle which makes it fast, safe and helps to reduce stress for many horses compared to other types of injection.
• Blood test analysis can differentiate between vaccinated horses and those who are infected with strangles, an important factor when screening horses who are new to a yard or involved in a strangles outbreak.

The primary Strangvac course consists of two vaccinations given four weeks apart. The horse’s immune system produces antibodies that specifically target the strangles bacteria, achieving beneficial levels of protection two weeks after the second dose has been given. Like most vaccines, boosters are then used to maintain that immunity over time, the frequency of dependant on the level of environmental challenge for your horse.

The horse’s immunity is then able (in up to 94% of cases) to significantly reduce clinical signs of strangles, including fever, loss of appetite, lymph node abscesses, a cough and depression. It is important to remember that as the vaccine isn't 100% effective (no vaccine is), a horse exposed to strangles can still be infected and able to pass the disease on to other equines.

Although the Strangvac licence currently requires a booster at two months in horses at high risk, research has also shown that horses’ immunity rises quickly following a booster vaccination given within six months and even after a year of their primary course. This suggests the immune system remains primed against the disease beyond the two-month window, and there is widespread optimism that strangles vaccination can be incorporated alongside the equine influenza vaccination program, though more frequent booster would be recommended for horses facing a higher risk of infection.

Strangles is endemic in the forest ponies, so if you feel your horse is at risk of direct contact with the forest ponies, or, for example, shares a water course, then please ring the practice to book a vaccination. Or speak to our equine vet Saara if you have any further questions.