The free-range flocks of chickens at two more farms in Norfolk hit by bird flu have all been killed, officials said on Monday.
About 15,000 birds have been slaughtered
The chickens at Norwich Road Farm and Mowles Manor Poultry Unit at North Tuddenham were slaughtered after tests showed they had the H7N3 strain.
Workers moved in on Sunday morning to begin the cull of about 15,000 birds.
A cull of 35,000 chickens at the nearby Witford Lodge Farm, where the latest outbreak started, ended on Saturday.
Restrictions to contain the spread of the virus are in operation in a 1km area around the affected sites and trading standards officials have offered fresh guidance to anybody travelling in the area.
'No more infection'
David Collinson, Norfolk County Council's head of trading standards, said: "I want to reassure people who might see the signs that the restrictions only apply to the movement of poultry, captive birds and domestic mammals, but not pets.
"The orders advise all bird keepers within a declared zone to maintain high standards of biosecurity, and any movements of poultry and other captive birds within the zone must be licensed by a veterinary inspector."
A spokeswoman for the Health Protection Agency (HPA) said that she was not aware of any more people becoming ill because of the virus.
So far only one poultry worker has contracted the H7 strain of bird flu in the form of conjunctivitis. Three others have tested negative for the disease.
The spokeswoman said about 60 people, including poultry workers and members of the State Veterinary Service, had been given anti-viral drugs to prevent them getting ill.