Video: Swamp fever found in UK again

Cross section of the EIA virus

Two cases were detected in Wiltshire in January, in two horses who had been imported from Romania through Belgium.

The latest case of the viral disease, also known as equine infectious anaemia, was found in a horse in Northumberland, the Department for Environment, Food and Rural Affairs (Defra) said.

The case sparked a warning from equine charity World Horse Welfare, which called on all British and mainland European horse owners to work together to stop what it called the real and increasing threat from several diseases.

Defra said the latest case was detected through routine post-import testing.

It said the horse, who arrived in a group of six horses from the Netherlands, will be euthanised in line with regulations.

The five other horses have so far tested negative to the disease.

The property remains under restrictions.

Chief veterinary officer Nigel Gibbens said: "These were apparently healthy horses carrying a notifiable disease that we are keen to keep out of Great Britain.

"After considering the risk I have decided to take appropriate action and humanely destroy this horse."

Once infected, horses are infected for life and can pose a risk to other horses in close proximity. The British policy is to put down infected animals.

World Horse Welfare says the latest case "could be the tip of the iceberg".

It noted that, since the end of August alone, there have been new outbreaks of the disease reported in Northern France (directly linked to horses imported from Romania), the Dordogne area, and Germany.

"While World Horse Welfare welcomes the news that Defra has acted so promptly in dealing with this case, today's news is extremely concerning and demonstrates the changing environment we're living in," Chief executive Roly Owers said.

"This is a real warning to us that we're sailing far too close to the wind. The concerning question is where these horses came from, given that Holland to date has not reported a case of EIA.

"With more and more horses moving across Europe, including the significant trade in low-value animals, not just slaughter animals, we're facing an increasing threat from the spread of disease."

EIA is endemic in both Romania and Italy. Romania is one of the largest exporters and Italy the largest importer of horses for slaughter in Europe.

Despite the legal requirement for health certification before exporting horses from Romania, which were tightened in June 2010, there continued to be cases of EIA across Europe, Owers said.

"World Horse Welfare advises owners to undertake rigorous checks when buying a horse from abroad and is discouraging anyone from importing Romanian horses.

"Owners should also ensure that any horse they buy or that comes on to their yard has a passport, is checked for a microchip and that isolation and biosecurity measures are strictly followed for any new entry on to the yard," he said.

"If this disease spreads across the UK it could have catastrophic effects on our horse population. Whether it's a child's pony or Cheltenham Gold Cup winner, disease does not discriminate."

World Horse Welfare produced a disease pack earlier this year, offering advice on the prevention and detection of diseases such as EIA. The charity continues to promote and distribute it to horse owners, livery yards, veterinary practices and other equine organisations in Britain.

It is currently being translated into Romanian for distribution through the charity's Project Romania campaign.

EIA is a virus disease of horses causing intermittent fever, anaemia, emaciation and death. It can be transmitted by the exchange of blood by biting insects and occurs typically in low-lying swampy areas.

It is not a risk to human health.