Defra has confirmed avian influenza in a single sheep in Yorkshire following repeat positive milk testing, with farmers urged to remain vigilant for the disease.
The case of H5N1 was identified following routine surveillance of livestock on a farm where avian influenza had previously been confirmed in captive birds.
Defra said on Monday (24 March) that there was no evidence to suggest an increased risk to the UK livestock population.
Livestock surveillance had been introduced on the infected Yorkshire premises, the department added.
The infected sheep had been humanely culled to enable extensive testing, and no further infection was detected in the remaining flock.
While this is the first time this virus has been reported in a sheep, it is not the first time avian influenza has been detected in livestock in other countries.
In the United States, more than 700 dairy herds have been infected across the country since last year, but mostly in California, government statistics show.
In December, the United States Department of Agriculture issued a federal order for the testing of the nation’s milk supply due to the surge.
Following the case in Yorkshire, the UK chief veterinary officer urged farmers and livestock keepers across the country to remain vigilant to the disease's clinical signs.
Dr Christine Middlemiss said strict biosecurity measures had been implemented on the farm to prevent the further spread of disease.
"We have confirmed the detection of influenza of avian origin (H5N1) in a single sheep on a farm in Yorkshire," she said.
“While the risk to livestock remains low, I urge all animal owners to ensure scrupulous cleanliness is in place and to report any signs of infection to the Animal Plant Health Agency (APHA) immediately.”
In line with the UK’s international reporting requirements, the case will be reported to both the World Organisation for Animal Health (WOAH) and the World Health Organisation.
The UK Health Security Agency (UKHSA) said that avian influenza "is primarily a disease of birds and the risk to the public’s health is very low, but people should not touch any dead or sick wild birds they find".
Dr Meera Chand, emerging infection lead at the agency said: “Globally, we continue to see that mammals can be infected with avian influenza A(H5N1).
“However, current evidence suggests that the avian influenza viruses we’re seeing circulating around the world do not spread easily to people – and the risk of avian flu to the general public remains very low.
“UKHSA has established preparations in place for detections of human cases of avian flu and will respond rapidly with NHS and other partners if needed.”
In January, it became mandatory for all poultry farmers and keepers in Britain to follow strict biosecurity measures to help protect their flocks as part of the Avian Influenza Prevention Zone (AIPZ).
The AIPZ measures apply to all poultry farmers and bird keepers whether they have pet birds, commercial flocks or just a few birds in a backyard flock.
There is also a mandatory poultry housing order in place across large swathes of England and all of Northern Ireland. Scotland and Wales are not included in this.
Avian influenza is notifiable in all poultry and other captive birds and influenza of avian origin is notifiable in both kept and wild mammals.
If the disease is suspected, it must be reported immediately to APHA. Failure to do so is an offence.
• 03000 200 301 in England
• 0300 303 8268 in Wales
• Contacting a local Field Services Office in Scotland
