The bets are off at Britain’s historic racecourses. Trainers across the country are nervously awaiting the results of tests from more than 100 stables after an outbreak of equine influenza has sparked fears that a new vaccine-resistant strain of the disease could plunge the industry into disarray.

Equine influenza

Feeling a little hoarse? The symptoms of equine influenza are similar to flu in humans, but it’s no joke to the racing industry which could potentially be shut down for most of the year in the event of an epidemic. (Image: ONE17)

The British Horseracing Authority took the decision to cancel all racing until next Wednesday at the earliest after three cases of horse flu were confirmed at a stable in Cheshire on Wednesday.

Earlier that day, the stable had sent a runner to races in Ayr, on the west coast of Scotland, and Ludlow, near England’s border with Wales, prompting fears that numerous horses from stables all over the country could have been exposed to the virus.

In the UK, vaccination is mandatory for almost all breeds used in competitive horse racing — and the fact that the horses that tested positive on Wednesday were vaccinated suggests a new, mutated strain of the virus has emerged.

Cheltenham Jeopardized

Equine influenza is rarely fatal and produces similar symptoms in horses as flu does in humans. But it is long lasting. Horses can take weeks or even months to recover.

The temporary shutdown is likely to cost the UK horse racing and betting industries tens of millions of dollars, but an epidemic would be catastrophic — almost certainly leading to the cancelation of most of the racing calendar this year.

The biggest event for UK horse racing — and also one of the biggest events of the year for the betting industry — is the Cheltenham Festival, which is scheduled to begin in just over a month.

The last time Cheltenham was canceled was in 2001 following an outbreak of foot and mouth disease.

An outbreak of equine flu in Australia in 2007 shut down racing for five months and the costs to eradicate the disease were estimated at $1 billion. Well over 10,000 horses — albeit from an unvaccinated population — were infected over a period of three months.

No New Cases in Early Tests

Because the incubation period for horse flu can be up to 72 hours, the BHA’s veterinary team waited until Friday to conduct tests at stables across the country.

Initial signs were good. The BHA said Friday that no additional horses had tested positive, but the disease can take up to a further three days before symptoms are visible, which means Sunday will be the earliest point at which a decision can be made as to whether racing can continue.

“This approach will allow samples to be collected and assessed by the Animal Health Trust in order that a fully informed decision can be made on Monday,” said the BHA in an official statement. “This may then allow declarations to take place on Tuesday in time for racing on Wednesday.”