Every horse is at risk of contracting flu (equine influenza), a highly contagious respiratory disease affecting the upper and lower respiratory tract in equines. It is caused by subtypes of the influenza A virus and is so contagious that any outbreak will trigger yards, competition centres and sporting venues to close down in an attempt to contain it.

Vaccination is widely available, affordable and the best way to protect horses. While no vaccine is 100% effective, immunisation is effective in limiting the spread of the virus and decreasing the severity of infection.

So if your horse isn’t currently vaccinated, make arrangements now.

According to Richard Freeman from insurance broker Lycetts, having an unvaccinated horse may even invalidate any horse health insurance policy you have if they become unwell with flu.

“It is commonly a condition [of an insurance policy] that the insured horse must be vaccinated,” he says.

Facts about horse flu

There are three crucial things that every horse owner should know about equine flu:

  1. It is highly contagious and every horse is at risk of contracting it.
  2. The virus can travel up to 5km in the air.
  3. It is easily passed on to horses via human touch and clothing.

Equine flu is transmitted by contact with the virus — either from infected horses, in the air, or via clothes, tack and tools. So even if your horse never leaves the yard, they are still at risk of exposure to the virus.

Although horse flu is rarely fatal, it is an unpleasant disease that can have far-reaching consequences, particularly financially in the loss of competitions and closing of yards.

Some groups of horses — youngsters, veterans, sick horses and mares in foal, for example — are more vulnerable to flu than others.

.In 2019 it was estimated that less than 50% of the UK’s horses were not vaccinated against flu, and to date many horses remain unvaccinated.

Signs of horse flu

Signs of infection appear as quickly as two days after initial exposure, and horses with flu remain infectious for up to 10 days following the onset of symptoms.

They may show any of the following signs:

If you notice any of these in your horse, consult your vet. If you see any symptoms or your horse has been in contact with infected horses, isolate them and call your vet.

Official advice is to not travel the horse anywhere, including competitions or lessons, if your horse is showing symptoms or has been in contact with infected horses.

Lessons learned from Covid-19

Thanks to the Covid-19 pandemic, people’s understanding of infectious disease has improved massively, and this is a good thing when it comes to vaccinating for things like equine flu and tetanus.

British horse owners faced a devastating flu outbreak in January 2019, when a new strain of equine flu was found in the UK. It was the highest recorded numbers of equine flu for many years and it brought horse racing and competition circuits to a halt.

The UK saw the highest number of outbreaks of any country, possibly due to the fact that the UK has a much lower level of vaccinated horses in comparison to Europe.

In 2019 it was estimated that less than 50% of the UK’s horses were not vaccinated against flu, and to date many horses remain unvaccinated.

“There were a couple of cases of equine flu at the start of 2020, but that is normal,” explains equine vet David Rendle MRCVS, former president of the British Equestrian Veterinary Association (BEVA).

“Some vet practices did stop vaccination for a short period [due to lockdown in March 2019], which may have caused some problems for people at the end of their vaccination programme, but that has been largely sorted now.”

Vaccination for horse flu

The worry, David says, is that people don’t keep up with vaccinations for horse flu, which increases the likelihood of another large-scale outbreak occurring.

“It is frustrating that historically horse owners haven’t appreciated the value of vaccination, as the scientific evidence is clear in that the only way to effectively protect the horse population is to have a high level of vaccination,” he says.

“There are certain sectors where the rate of vaccination isn’t high, and those horses are at higher risk of having more problems and potentially dying as a result. These sectors also undermine the hard work put in by other sectors of the industry.

“Hopefully people’s understanding of infectious disease has improved as a result of Covid and they’ll see that vaccination is the only way to control a highly infectious disease in a constantly moving population.”

Six monthly boosters

There was a shortage of equine flu vaccines in 2022, but expert advice by the end of that year was to revert to bi-annual booster jabs for horses who had already received their primary course of equine flu vaccinations four weeks apart.

Keeping up to date with six-monthly vaccinations is still the recommended choice, but a yearly vaccination is infinitely better than nothing.

Of course if you compete your horse, you will need to make sure they are vaccinated in line with the governing body’s requirements. Consult the rulebook to find this information.

“Twice a year is much better at protecting the population which is why performance horses have now been moved toward six-monthly vaccinations for flu,” explainss David.

“We know it is unrealistic to expect everyone to vaccinate six-monthly, but everyone should vaccinate once a year as a minimum and then administer additional boosters if they are moving and mixing their horses. We need to act together to keep our horses safe.”

It’s a date!

If you horse isn’t already vaccinated for equine flu, book them in with your vet as soon as possible. As a guide, primary and secondary vaccination is given approximately four weeks apart, followed by a booster six months later. After this, a booster should be administered every six or 12 months.

Your vet will be able to advise what the most appropriate vaccination schedule is for your individual horse. Save the booster date as an annual reminder in your phone and remember to put it into your diary and/or on the calendar in your kitchen or tack room.

In my experience, vet practices are also very good at sending out reminders of an impending booster due date and will make sure you get booked in in good time.

You can often save yourself a call out fee by booking in for a vaccination day. This is when a vet will visit all the horses in your area who are due for a booster around the same time.

Main image: copyright Shutterstock

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