Vaccinations are a means to reduce the incidence of disease, in particular Equine Influenza, Equine Herpes Virus (EHV) and Tetanus . They should only be carried out on healthy horses. Most livery yards, racecourses and competition centres will require any horse coming onto the premises to have proof that their immunity is up to date, and all injections are therefore recorded in a horse’s passport.

Vets are unable to backdate injections in a passport, so timings of boosters need to planned ahead to ensure that they are not given too close to key dates, in particular for competition horses or broodmares.

Competition rules

If you wish to compete your horse or pony, the governing body will state which regulations they expect you to follow. in the UK, riding club, pony club and affiliated events all adhere to the racing authority rules. No vaccination should be given within the 7 days preceding competition

Influenza protocol
  • A primary course is two injections not less than 21 days or more than 92 days apart.  It is most common to give the second vaccination 3 – 6 weeks after the first.
  • A  first booster must be given 5 – 7 months (not less than 150 days and not more than 215 days) after the second injection of the primary course.
  • Thereafter, annual boosters are given not more than 12 months apart.
  • To compete under FEI rules a booster vaccination must be given within 6 months + 21 days of the competition.
  • No vaccination is to be given within 7 days of competition.

If at any time an injection is given later than this protocol, the whole sequence must be started from the beginning, including the 5 – 7 month booster.

Tetanus protocol

Tetanus is caused by the production of endotoxins by the bacteria Clostridium tetani, which is found in soil and enters the tissues via wounds. It is often fatal, so all horses should be vaccinated against tetanus even if they do not travel or mix with others. Tetanus vaccination is commonly combined with influenza vaccination. When using separate vaccines, the tetanus vaccination schedule is as follows:

  • Primary course – two injections 4-6 weeks apart
  • First booster within 12 months of the second primary injection
  • Subsequent boosters are only needed every 2 years
EHV 1 & EHV 4  protocols 

In some cases  an equine vet will recommend vaccinating against other diseases such as EHV and rotavirus, particularly for competition horses or broodmares.

With regard to EHV vaccines, currently there is a world shortage of the attenuated vaccine commonly used in Europe. The “killed” vaccine, Pneumobort K” is being shipped in from the USA, but is probably not as efficacious. This will create a big issue for studs in the next northern hemisphere season.

Strangles Vaccine

An estimated 600 outbreaks of strangles occur each year in the UK alone, so the development of a vaccine is of interest to many owners. A protein-based strangles vaccine is being developed by a group of scientists from the Animal Health Trust (AHT), the Swedish University of Agricultural Sciences, the Karolinska Institute and Intervacc AB.  It is anticipated that it will be available in 2020.