The agriculture department said late Saturday that the strain of foot-and-mouth disease found on a farm in southern England was identical to one used at a research laboratory a few miles away shared by the government's Institute for Animal Health and a private pharmaceutical company, Merial Animal Health. The department said the strain had not recently been seen in live animals.
"This is a promising lead but we do not know for sure," Environment Secretary Hilary Benn told the British Broadcasting Corp. on Sunday.
Cattle on a farm outside Wanborough, about 30 miles southwest of London, tested positive for the disease, which affects cloven-hoofed animals including cows, sheep, 바카라사이트
pigs and goats. It does not affect humans.
The agriculture department said there had been no movements of livestock from the affected farm since July 10, raising hopes the virus might not have spread further.
Benn said reports of symptoms at four more premises had been investigated and found not to be foot-and-mouth.
The highly infectious disease, which devastated the rural economy when it spread across Britain in 2001, can be transmitted though contact between animals, or on the wind.
Officials said they had begun an urgent review of biosecurity at the Institute for Animal Health's Pirbright Laboratory. The government-funded lab, which researches the disease and tests foot-amd-mouth samples, is about 4 miles from the affected farm.
Benn said health inspectors would be visiting the laboratory site Sunday.
Microbiologist Hugh Pennington said that "on the balance of probabilities, this is where the virus came from."
"There are other possible sources of the virus, but they are looking pretty remote," Pennington told the BBC.
He said airborne transmission was one way the virus could have spread from the lab to the nearby farm.
"It may not be a huge security breach," Pennington said. "It may just be one incident which let a puff of virus out."
The government's chief veterinarian, Debby Reynolds, ordered a new 6-mile protection zone to be set up around the farm and the lab.
She said the virus was not one found in animals, and instead matched a strain being held at nearby disease-research and vaccine production facilities.
"This is a strain ... that is contained in the Pirbright facility and is associated with vaccine production," Reynolds told Sky News television.
However, she said officials were still investigating other possible sources for the infection.
The Department for Environment, Food and Rural Affairs, or DEFRA, said the strain was present at the government lab and was used in a vaccine batch manufactured last month by a pharmaceutical company which shares the site. The company, Merial Animal
Health the British arm of Duluth, Georgia-based Merial Ltd. said it was suspending manufacture of the vaccine as a precaution.
Martin Shirley, director of the Institute for Animal Health, said the strain had been in "limited use" within the institute's own laboratory in the past four weeks but an investigation had found no breaches of biosecurity procedures.
Britain banned exports of livestock, meat and milk and halted the movement of cattle, sheep, goats and pigs nationwide in a bid to prevent
the spread of the virus.
The United States and Japan immediately banned British pigs and pork products in response to the outbreak. British beef is already banned in both countries because of mad cow disease.
The European Union was also likely to announce a ban on British livestock imports in the 27-nation bloc when its executive body meets on Monday.
Livestock on the affected cattle farm were slaughtered Saturday, and animals at a second farm next to the first were also culled.
The case is the first in Britain since 2001, when the carcasses of many of the 7 million culled cattle were burned on huge pyres that dotted the country. The farming industry was devastated, huge swaths of the countryside were closed and rural tourism was badly hit.
The total cost to the country was estimated at $16 billion.
Prime Minister Gordon Brown vowed to work "night and day" to avoid a repeat of the 2001 epidemic.
"Our first priority has been to act quickly and decisively," said Brown, who returned to London from a summer holiday to deal with the outbreak.