Equine Vaccinations
Vaccinations explained
Vaccinations are biological products used to stimulate the immune system to fight off a disease without actually infecting the animal with the disease. They do this by mimicking the disease agent (usually a virus, a bacteria or a bacterial product) and making the body think that it has been infected so that it mounts an immune response. The immune systems basic response is to make antibodies which then kill off the disease agent, although there other more complicated responses that are too technical to cover. The process works because special cells retains a ‘memory’ of the disease agent and are able to respond by quickly making antibodies if they ever encounter the disease agent again, hopefully eliminating it before it's able to infect the animal.
Most vaccines require an initial course of several doses a few weeks apart to establish a good immunity to infection. The need for further vaccination and the frequency of these depend on the vaccine and the disease being vaccinated against.
Common vaccines used for Equines
TETANUS – All horses should be vaccinated for tetanus. It is widespread in the soil and can enter the body through any break in the skin. Once infected treatment is almost impossible and incredibly traumatic for all involved. The initial course is 2 injections 4 weeks apart (usually given combined with first 2 flu vaccs) and then boosters every 18-24mths. Pregnant mares should receive a tetanus booster 6 weeks before they are due to foal to ensure there are lots of tetanus antibodies in the colostrum for the foal as the foal will not be born with any immunity to tetanus. Foals can be given an anti-toxin injection at birth to cover them until the antibodies from the colostrum have been absorbed. Foals should then be vaccinated from 4mths of age as the antibodies from the colostrum will start to wear off by this time.
EQUINE INFLUENZA (EI) – This is a virus that causes respiratory disease in the horse and is highly contagious. The disease is rarely fatal but can cause significant coughing and lethargy and can take many weeks to recover from. Most competition/show organisations require horses to be fully vaccinated against EI before they can compete. Generally this means they should have had the first 2 vaccinations for EI given 21-92 days apart. The first booster (3rd vacc) is due 150-215 days after the 2nd injection. After this inital course the vaccination is required every 365 days so if you miss your vaccination due date you would be required to start the whole course again. If you are competing at an FEI or jockey club event then you are required to adhere to their vaccination guidelines. The FEI guidelines :
EQUINE INFLUENZA VACCINATION
From 1 January 2005 onwards, influenza vaccination for all horses competing in FEI competitions requires a vaccination within six months + 21 days of the competition.
1. All horses intending to participate in FEI competition must have at least received an initial primary course of two vaccinations, given between 21 and 92 days apart. Thereafter, a third dose (referred to as the first booster) must be given within 6 months + 21 days after the date of administration of the second primary dose, with at least annual boosters given subsequently (i.e. within one year ofthe last dose).
2. If the horse is scheduled to take part in an FEI competition, the last booster must have been given within 6 months + 21 days of arrival at the FEI event. (The 21‐day window has been provided to enable vaccination requirements to fit in with the competition schedule).
3. No vaccination shall be given within 7 days of the day of arrival at the FEI event.
4. All horses that were certified as correctly vaccinated under the previous FEI equine influenza
vaccination rule prior to 1st January 2005, do not need to start a primary course again provided that
they have complied with the previous rule of primary course and annual re‐vaccinations and the
new rule of a booster vaccination within 6 months + 21 days of the day of arrival at the FEI event.
EQUINE HERPES VIRUSES 1 & 4 – contagious respiratory infections that can cause abortion. Vaccination against this is less common than influenze because there is no Jockey Club or FEI requirement for it and it's less likely to cause serious illness. However, infection can require several weeks off work to recover from and for this reason we reccomend high performance horses are vaccinated. Pregnant mares should also be vaccinated to reduce the rist of abortion. The initial course is two injections, four to six weeks apart and then 6 monthly boosters to maintain immunity. To help reduce risk of abortion injections must be given at five, seven and nine months of pregnancy. foals can be vaccinated from 5mths of age.
ROTAVIRUS – vaccination against rotavirus is carried out to prevent outbreaks of rotaviral diarrhoea in young foals. Mares are vaccinated at eight, nine and ten months of pregnancy and the antibodies transferred via the colostrum to the foal.
N.B. It is recommended that horses are not allowed to become 'sweaty' for 24 hours after the vaccination is done as this may cause an adverse reaction.
