The British government said today that there was no proof that the latest outbreak of bird flu at a Turkey farm in Suffolk came from Hungary.
Food and Rural Affairs Minister Lord Rooker said that even if the DNA structure of the H5N1 virus involved turned out to be the same as the one involved in the Hungarian outbreak, this would not prove that the British outbreak had originated there.
He said that since October last year, 354,745 live turkeys were imported to the UK.
He added: "These include 141,046 day-old chicks from within the EU. Figures for imports into the UK of live day-old turkey chicks from outside the EU are not currently available.
"All consignments of live birds are liable to documentary and identity checks. These must come with an official health certificate guaranteeing compliance with EU rules and freedom from disease."
Meanwhile British health experts were today expecting more workers at the at the Bernard Matthews farm in Holton, Suffolk, to report illnesses.
Officials at the Health Protection Agency (HPA) said it was "probably inevitable" that more people would report ailments and need checks.
Experts said precautionary tests would be carried out but they do not expect anyone to test positive for the H5N1 virus.
Two people who worked have undergone tests for the bug.
Analysis showed that neither was infected. A vet was checked at a hospital in Nottingham on Tuesday and a farm worker was tested at a hospital near Great Yarmouth, Norfolk, yesterday.
"It's the time of year when people are getting colds and viruses," said an HPA spokeswoman. "Anyone with those symptoms who has been at the farm is likely to be concerned. It's probably inevitable that more people will report illnesses."
HPA flu experts said yesterday that people who work at the farm should not become infected because all necessary precautions have been taken.
HPA flu expert Dr Jonathan Van Tam said: "We are not expecting any workers to test positive for avian flu as they have followed all the necessary precautions in terms of protective clothing, hygiene measures, and have been offered antiviral drugs.
"We are, however, expecting to see a number of workers with symptoms caused by other non-flu respiratory viruses over the coming week as this is the time of year when we see an increase in these infections. We will assess these cases as they occur."
The Department for Environment, Food and Rural Affairs (Defra) expects to complete cleaning and disinfecting sheds which housed the infected turkeys today.
Earlier this week all 159,000 turkeys at the farm were slaughtered to prevent the disease spreading. Vets confirmed H5N1 at the farm on Friday after significant numbers of birds started falling ill three days earlier.