Britain raced to avert economic disaster Saturday by halting meat and dairy exports and the movement of livestock around the country after foot-and-mouth disease was found on a southern English farm.
Prime Minister Gordon Brown vowed to work "night and day" to avoid a repeat of a 2001 outbreak, when millions of dead animals were burned on pyres, swathes of the countryside were closed, rural tourism was badly hurt and British meat was shut out of international markets.
"Our first priority has been to act quickly and decisively," Brown said. "I can assure people ... we are doing everything in our power to look at the scientific evidence and to get to the bottom of what has happened and then to eradicate this disease."
The Department for Environment, Food and Rural Affairs, or DEFRA, said Britain had banned the export of live cattle, pigs, sheep and goats, as well as carcasses, meat and milk.
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.
British authorities also imposed a nationwide ban on transporting cattle, sheep, goats and pigs in response to the outbreak.
Foot-and-mouth disease causes fever and blister-like lesions on the mouths, teats and hooves of affected animals. It can be deadly in livestock but is harmless to humans.
Although many animals recover, the disease leaves them debilitated, causing major losses in meat and milk production.
DEFRA said animals on a farm near Wanborough, about 30 miles southwest of London, had tested positive for the disease, which affects livestock but not humans. Officials did not specify how many animals were infected, but said all livestock on the farm were slaughtered and incinerated.
Scientists were carrying out tests to determine the strain of the disease, and whether vaccinations could be used to try to halt its spread.
The government was criticized for not using vaccines to try to fight the 2001 epidemic. A report on that outbreak by a senior scientific body, the Royal Society, concluded that vaccinations should be a major tool of first resort in the event of future outbreaks.
The government's chief veterinarian, Debby Reynolds, said it was too soon to determine how the disease had shown up again in Britain -- whether through the illegal movement of animals, on the wind or by accidental contamination -- or how far it may have spread.
The government-funded Institute for Animal Health's Pirbright Laboratory, which is researching the disease, is about four miles from the affected farm. Authorities have asked the lab to review its biosecurity procedures, Reynolds said.
No one at the laboratory returned a phone message seeking comment Saturday.
Reynolds said there had been a small number of reports of signs of illness among livestock on other farms in the country, but none had so far proved to be foot-and-mouth disease.
Farmers near the infected site said they were hopeful quick action would contain the disease.
"We are keeping our fingers crossed but there is really nothing we can do about it except wait," said Michael More-Molyneux, whose farm is about five miles from the infected site.
The 2001 outbreak started with a pig herd in northern England and quickly spread to cows and sheep. It eventually infected animals on more than 2,000 farms and shut Britain out of the world's livestock export markets. The total cost to the country was estimated at $16 billion.
It took a year before Britain was declared free of the disease, and months more before British exports were allowed to resume.