Equine Vaccinations

The two most routinely administered vaccinations are for influenza and tetanus.


This is a highly contagious respiratory disease caused by several different strains of the influenza virus. A horse usually contracts the virus from other infected horses, which may not demonstrate obvious infection. The incubation period can be several days before signs of disease are seen, although the virus can be spread during and after this time. Signs of influenza in horses are similar to those seen in humans, although it is not the same virus!

  • High temperature for 1-3 days
  • Lethargy
  • Loss of appetite
  • Clear nasal discharge progressing to thick, green-yellow colour.
  • A harsh, dry cough that can persists for 2-3 weeks or more.

  • The disease leaves the horse susceptible to secondary infections and can develop into a much more serious illness such as bronchitis or pneumonia.

    Outbreaks of influenza are most common when large numbers of young horses are brought together in stressful conditions, i.e. sales or shows.  Therefore, many equestrian organisations insist that horses hold current vaccination cards showing continuous cover and vaccination against influenza. This is now mandatory for all horses using racecourse premises.


Tetanus is caused by a bacterium found in soil, Clostridium tetani. The bacteria enter the horse's bloodstream via an open wound. Even small wounds can allow contamination and because the incubation period is 1-3 weeks, the wound has usually healed by the time the signs of disease are apparent. The initial signs of disease are vague stiffness and reluctance to move. As the disease progresses, the more classic indicative signs develop: muscle spasms of the head and neck resulting in difficulty chewing, nostril flaring and a wide-eyed expression. The affected horse then develops generalised trembling, leading to violent, whole body spasms in response to sudden movements or noise. 

Approximately 90% of unvaccinated horses that develop tetanus die. In the small number of horses that do recover, intensive veterinary treatment and nursing care is required for a period of about 6 weeks. Due to the poor prognosis for any horse that contracts this disease we recommend that all horses are vaccinated against tetanus, as prevention is the only sensible option.

Tetanus vaccination course:

  • Vaccinations can start from 3 months of age.
  • Initially 2 injections should be given 4-6 weeks apart
  • The first tetanus booster should be given a year later
  • Thereafter boosters are only required every 2 years

Pregnant Mares

Mares should be given a tetanus booster in the last 4-6 weeks before foaling, to ensure the foal is protected in the first 6-12 weeks of life. If the mare hasn’t been vaccinated the foal may be covered with an ‘antitoxin’ (an 'antidote' to the tetanus infection) in the first 24hrs of life. 

Flu Vaccination Course:

Approved vaccination schedules for the influenza vaccine are published by the British Horseracing Authority, International Equestrian Federation (FEI) and various show societies and these form part of the entry requirements for horses competing or racing at their events. 

Unfortunately, these schedules differ between organisations and it is confusing for the owner to determine which they should follow. To complicate matters further, the manufacturers of each vaccine recommend a different schedule again, based on the efficiency of their vaccines determined by clinical trials.  However, if you follow manufacturers recommendations they will meet with the approval of the BHA and most show organisers regulations, which are: 

  • Vaccinations can start from 4 months of age.
  • The 1st and second injections are given 4-6 weeks apart
  • A 3rd is given 5-7 months after
  • Thereafter annual boosters giving Flu or Flu & Tetanus in alternate years

Commonly the flu vaccination schedule is combined with the tetanus vaccination course to provide cover for both diseases in one injection.

Vaccination compliance - Flu vaccinations for horses and ponies

The British Horseracing Authority (formerly The Jockey Club) has laid down exact rules that must be followed for horses entering BHA premises (i.e. racecourses) or competitions. Certain societies require the same compliance, examples of which are:

            British Horse Trials Association
            British Endurance Riding Association
            British Horse Driving Trials Association
            British Riding Club
            British Show Jumping Association (when competing internationally)

This list is not exhaustive. The BHA rules regarding ‘flu vaccinations are:

The second dose of a course of ‘flu vaccine must be given between 21 and 92 days after the first.

  • The third dose must be given between 150 and 215 days after the second.
  • Subsequent doses must be given within 12 months of the previous one. It is acceptable (but not recommended) to boost on the same date as previously.
  • The horse may not compete until the 8th day after the last vaccination. 

When competing under Federation Equestre Internationale (FEI) rules, the horse must be vaccinated every 6 months, rather than annually.

Vaccination guidelines

In order to minimize any adverse reactions to any vaccination given, we recommend that you follow these guidelines:

  • Your horse's coat should be clean and dry before vaccination
  • The horse should have done no heavy exercise in the last 2 hours prior to vaccination
  • The vaccinated horse should then not be given heavy exercise for 24-48hrs

Adverse reactions

If your horse or pony ‘reacts adversely’ to a vaccination, or indeed to any medication, you should inform us as quickly as possible, telephone 01291 672637.  The reaction may simply be a swelling at the site of injection, which can be relieved using warm compresses, or there may be stiffness, which makes movement difficult (e.g grazing, if the injection was in the neck). More serious reactions include sweating or mild colic. Some horses tolerate certain vaccines perfectly well, but react to those made by another manufacturer. If you are aware of a previous reaction, this should be made clear to our staff at the time of booking your appointment.

To book your horse's vaccination appointment telephone 01291 672637.  We can arrange a call out visit, it may be possible to share this call out with other horseowners on your yard.  Alternatively you are welcome to arrange to bring your horse to either our Usk or Caerleon surgeries.  Please discuss your requirements with our receptionist when you telephone to make your appointment.

Equine Microchipping.

Our Main Vet Centre in Usk is supported by surgeries in Caerleon and Pontypool

Which enable us to provide veterinary services throughout Monmouthshire, Newport and Torfaen including Abergavenny, Gilwern, Goytre, Cwmbran, Chepstow, Blaenavon, Blackwood, Newbridge, Risca, Magor, Caldicot, Tintern and Trelleck.