Vaccination myths

There is limited research on how many horse owners vaccinate their horses, and adhering to vaccination guidelines does seem to differ geographically across the country. On the Horse First Aid Courses that I run all around the UK compliance with vaccinations is generally quite high, but sometimes only half of owners admit to not vaccinating their horses. Personally I find this really surprising as vaccinations are an essential part of preventative health care, just like shoeing or trimming, worming and dental care, and aren’t particularly expensive.

In this country horses are commonly vaccinated for Equine Influenza and Tetanus, and generally a combined vaccination which is given. Animals involved in breeding may well also be vaccinated for Equine Herpes Virus as well.

So why don’t more owners vaccinate their horses?

Personally I believe that the main reason is a misunderstanding about vaccinations; as with many other areas of the equine world there are lots of myths and ‘Old Wives Tales’. With that in mind here are six popular vaccination myths that I hear on our courses, and why these shouldn’t stop you vaccinating your horse.

1. My horse is old (or young) … he doesn’t go anywhere so doesn’t need vaccinating

 

This is a common reason I hear for owners not vaccinating their horses, but this is incorrect for several reasons.

Firstly a vaccination will provide cover against Tetanus which is a life threatening disease caused by a toxin released by a bacteria called Clostridium tetani. This bacteria lives in the environment, and infection from Tetanus occurs when the bacteria enters the body, generally via a small wound.  Tetanus affects all domestic animals (and humans), but the horse is the most susceptible. Horses are also very prone to wounds, and spend a lot of time in a muddy environment. Prognosis is very poor, and sadly most cases don’t survive. So tetanus doesn’t mind if your horse never leaves the field, or if they are old or young.

This is not an infectious disease and not passed from horse to horse, and there really is no reason not to vaccinate a horse for tetanus.

There are also very strong reasons to vaccinate your horse for Equine Flu, even if they never leave the field. Consider how much ‘horse traffic’ there is in your yard, and which other horses your own horse interacts with. There are very few horses who don’t mix with any other horses, so there is still a risk from an infectious disease such as Flu. It should also be highlighted that an older (or a younger horse) may have reduced immunity, so could benefit more from the protection that a vaccination would offer.

 

2. I’ve got too many horses to vaccinate them all, so I just vaccinate a few and they will all be protected.

Again this is incorrect, particularly in regard to tetanus where without a vaccination the horse is not offered any protection at all.  Although vaccinating your horse will help to contribute to the overall health of the equine population, there is no magic way that the benefits of a vaccination can ‘jump’ from horse to horse. Vaccinating against an infectious disease such as Equine Flu can help (together with effective biosecurity measures) reduce the chance of a disease outbreak, but this is certainly not guaranteed.

A vaccination stimulates an immune response which helps protect the animal if it has contact with the disease at a later date, and it is the best safeguard we have against Equine Flu. It is estimated that up to 85% of all horses would need to be vaccinated to protect the majority of a herd so vaccinating only a few animals won’t work.

3. It’s a waste of money

In actual fact vaccinations are generally very reasonably priced, (probably around the cost of a lesson), and owners really should ask themselves if they can afford NOT to vaccinate their horses?

There are significant financial implications with an outbreak of Equine Flu in a yard. The centre will be ‘closed down’ with no hacking or competing for several weeks or even months, there will be many associated costs, numerous vet visits, and potential loss of business as well; not to mention lots of very unwell horses.

Tetanus is treated with intensive nursing, and the cost of this will easily run into thousands of pounds and sadly the prognosis is very limited. Of all the vets that I work with only a few have had a successful outcome when treating a tetanus case, and most horses are  euthanised.

In order to make vaccinations affordable, and to improve uptake many practices offer a practice plan where you pay for vaccinations (and other routine care) on a monthly basis. Other practices offer a no-visit fee on set days, again making vaccinations very reasonable with a little bit of forward planning. Have a chat to others at your yard, perhaps you could combine a visit with a few other owners to keep the costs down.

 

4. My horse has had loads of vaccinations… he will have immunity by now

This is another popular reason that owners don’t want to vaccinate their horses. Many owners believe that horses are ‘over-vaccinated’, and that they don’t need an annual booster. Whilst your horse is not going to lose all benefits of the last vaccination once exactly 365 days have passed there is no evidence that protection can last longer than current vaccination guidelines dictate.

Research shows that antibodies produced in response to a Flu (or a combined) vaccination start to decline after 6 months, but adequate cover is still offered for most leisure horses up to 12 months, hence an annual vaccination was historically recommended. This decline in antibodies after 6 months is the reason that horses competing under FEI rules are required to have a booster twice a year, and why during a flu outbreak many owners choose to give an additional booster at 6 months. Horses competing under affiliated rules (such as British Showjuming, British Eventing and British Dressage) now need a 6 monthly booster, and it is well worth checking the policy of training and competition centres that you wish to attend.

With Tetanus vaccinations, owners are often surprised that horses need to be given annual (if combined with flu), or bi-annual vaccination (Tetanus only) because humans receive boosters quite infrequently. Humans may receive a Tetanus booster every ten years depending on risks for that individual. Naturally there is a danger of extrapolating from other species, and we shouldn’t forget that horses are most susceptible to tetanus, live in the perfect environment for Tetanus bacteria, and are prone to cutting themselves.

It is certainly better safe than sorry with regard to vaccinations, and not sticking to guidelines for boosters will mean that your horse won’t be able to compete in the future without starting the entire course again.

 

5. My horse isn’t competing so doesn’t need vaccinating

Whilst the need to comply with competition rules is probably a motivating factor for many owners to keep up with annual vaccination boosters, it is certainly not the only reason to vaccinate your horse.

As outlined very few horses live in complete isolation, just because you don’t compete your horse that doesn’t mean he or she doesn’t come into contact with other horses. Consider your horse’s stable and field mates, they probably do mix with other horses, and attend training clinics and competitions. Many yards have limited or no isolation procedures in place, so what about when a new horse arrives? A vaccination is not a guarantee that your horse won’t catch Equine Flu, but if this does happen your horse will certainly be less unwell with it, in a similar way to humans who have received a Flu vaccination.

As already mentioned there is no reason not to vaccinate your horse for Tetanus as the bacteria is present in your horse’s environment, regardless of their age or workload.

 

6. A vaccination will make my horse unwell

Sometimes horses do have a reaction on the vaccination site and an abscess can occur, although this isn’t actually that common. Chat to your vet if this has happened before as many vets will vaccinate into the pectoral muscles instead of the neck. If the horse does have a reaction it will drain much better in the chest, and cause less discomfort to your horse. It is very rare that horses do have a bad reaction to a vaccination, but in the unlikely event of this happening you must inform your vet as this would need to be reported to a vaccination manufacturers.

I hope that this article has helped you to understand the importance of vaccinating your horse. We all want to keep our horses happy and healthy, and vaccinating are such an essential part of their care. There is certainly some misunderstanding around vaccinating and I know that owners find our vaccination ‘myth busting’ on our Horse First Aid Courses really useful. If you’re unsure about whether your horse needs a six monthly booster then have a chat with your vet, who can help you assess the risk for your horse.