Regular vaccination of horses, ponies and donkeys is an important part of their primary care to prevent some serious, and potentially life-threatening, diseases. Furthermore owners of competition horses should be aware that an up to date vaccination record is a requirement of many sporting governing bodies for horses competing under their rules (eg. HRA, FEI, BE).

The following is a list of  diseases against which horses are most commonly vaccinated in the UK:

Equine Influenza (Flu)

Influenza is a viral infection which most commonly affects young horses. The virus affects the respiratory system resulting in a high fever, runny nose and coughing. Though rarely fatal, it can be a very debilitating disease. A number of disease outbreaks have occurred amongst unvaccinated animals in UK over the last few years.

To provide effective immunity against influenza your horse should be given an initial primary course of 3 vaccinations. Following the first vaccination the second needs to be given 21 to 92 days later. The third vaccination needs to be given 150 to 215 days after  the second and then booster vaccinations given annually, within 365 days . The primary course may be started any time after your horse is 5 months old.

Many sporting governing bodies, including HRA and FEI, have strict rules that dictate that a horse must be vaccinated against influenza in order to compete in competitions held under their rules.

Under HRA rules, a horse may compete 7 days following the second booster vaccination of the primary course. Additionally the horse must have a third booster vaccination given between 150 and 215 days after the primary course and thereafter have its annual booster vaccination within each calendar year.

Under FEI rules, a horse may compete 7 days following the second booster vaccination of the primary course. Additionally the horse must have further booster vaccinations every 6 months (actually must be given within 6 months +/- 21 days).

Any of our vets will be happy to check your horse’s vaccination record before competition. Please be aware that a lapse in the vaccination history (even by a few days, years before) will be considered as a breach of the regulations and may result in your horse being unable to compete or fines being imposed.

It is your responsibility to ensure that your horse receives its vaccinations at the correct time although we will endeavour to send out a vaccination reminder to remind you when your horse requires its vaccinations. Despite our best efforts these systems are not infallible and it remains your responsibility.


All horses and donkeys should be vaccinated against tetanus.  Tetanus  is usually a  fatal condition in the horse. Tetanus is caused by production of endotoxins by the bacteria, Clostridium tetani. The spores of this bacteria are commonly found in the soil and may be present in horses’ faeces and may enter the tissues via wounds. Deep puncture wounds are particularly dangerous as they provide an ideal site for infection as the bacteria thrive in anaerobic (low oxygen) environments.

Effective immunity against tetanus requires a primary course of two vaccinations given 4-6 weeks apart, followed by a booster 12 months later. Thereafter subsequent vaccinations can be given at 2 yearly intervals. Foals will receive antibodies from their mother’s colostrum and milk that will protect them for the first few weeks of life. Many foals are given tetanus anti-toxin shortly after birth as extra protection. Primary vaccinations are usually started in a horse over the age of 5 months but tetanus vaccination may be recommended in younger animals in some cases. Tetanus vaccination is often given as a combination vaccine with equine flu.

If your horse has not been vaccinated or vaccination programme has lapsed and it sustains a wound it is essential that a tetanus anti-toxin injection is given as soon as possible to prevent tetanus infection.  This is not the same as a vaccination but will protect your horse against tetanus for approximately 3 weeks.

Equine Herpes Virus (EHV) 

There are 5 types of Equine Herpes virus but EHV 1 and EHV 4 are the most clinically important and they are the only types which can be vaccinated against.

EHV 1 and 4 can cause a flu-like respiratory infection in horses but may also cause abortion in pregnant mares and severe neurological disease.

To provide effective immunity against respiratory and neurological disease caused by EHV 1 and EHV- 4 a primary course of 2 vaccinations should be given followed by a booster vaccination every 6 months.

  • 1st vaccination: Can be given to any horse over the age of 5 months.
  • 2nd vaccination: To be given 4-6 weeks after the 1st vaccination.
  • 6 month booster: To be given within 6 calendar months of the 2nd vaccination.

To provide effective immunity against abortion caused by EHV 1 and EHV-4 a course of three vaccinations should be given to a mare during her 5th, 7th and 9th months of pregnancy.