Doctors check poultry farm staff in latest bird flu crisis
Medics said there was no sign that anyone had become ill as a result of the virus in chickens at the farm in Norfolk.
But 35,000 chickens at Witford Lodge Farm, Hockering, were being slaughtered and incinerated as the Department for Environment, Food and Rural Affairs (DEFRA) tried to ensure the virus did not spread.
Vets said the virus at the farm, owned by Banham Poultry, was believed to be the H7 strain - not the H5N1 that has killed scores of people in Asia.
But Health Protection Agency officials said H7 could make people ill and had killed a vet in Holland three years ago. All precautions were being taken. The outbreak emerged only weeks after a wild swan, found dead in Cellardyke, Fife, tested positive for H5N1. The swan remains the only known UK case of H5N1.
Dr Sue Ibbotson, East Anglian director of the Health Protection Agency, said a dozen workers at the farm - plus staff involved in destroying the birds - were being monitored and offered anti-viral drugs.
"There is no need for panic," she said. "People living in the area should carry on with their lives as normal. They can still walk in the countryside. They can still eat poultry, providing it is properly cooked.
"There is a risk to the human population amongst those who are in very close contact with infected birds. The people most at risk in this case are poultry workers and people involved in the destruction of the birds.
"The people working at the farm are being monitored and have been offered anti-viral drugs. We are not aware of any reported illnesses."
Dr Ibbotson said people who became infected could suffer flu-like symptoms or eye irritations. Anyone living nearby who had been in contact with chickens from the site and was concerned should contact a doctor, she added.
Heather Peck, DEFRA's regional operations manager, said scientists were continuing to analyse samples taken from the birds. But she said all evidence pointed to the strain being H7 and there were no indications of it being H5N1.
DEFRA officials said the birds were being gassed or electrocuted and incinerated away from the farm.
Anthony Greenleaves, chief veterinary manager of the State Veterinary Service (SVS) in East Anglia, said birds at the farm had shown signs of illness a week ago and scores had died.
Daily death rates had then risen from around 15 to 80 and a vet had been called in. Tests then revealed avian flu and SVS officials had moved on to the farm on Wednesday.
He said Banham Poultry staff had acted properly and followed proper procedures. There was no reason to believe the virus would spread in the way the cattle disease foot and mouth might.
He hoped slaughtering the flock and disinfecting the site would prevent the virus from spreading.
DEFRA said compensation would be available to Banham Poultry.