(CBS/AP) Britain's health and safety agency determined Tuesday there is strong probability a foot-and-mouth disease outbreak in southern England originated at a vaccine laboratory, and said it was looking at the possibility the disease was spread by human movement.
The outbreak was discovered on a farm just four miles from the Pirbright vaccine laboratory, which is shared by the government's Institute for Animal Health, or IAH, and a private pharmaceutical company, Merial Animal Health, the British arm of Duluth, Georgia-based Merial Ltd.
There is a "real possibility" the disease was spread by human movement, and the possibility it was transmitted by air or flood water was "negligible," the government's Health and Safety Executive said in its initial report.
Environment Secretary Hilary Benn said in a statement the possibility that the strain had been released by human movement would be urgently investigated further.
"This will involve further interviews with personnel at the site. I have asked for a further report on these investigations as soon as possible," Benn said.
Benn said footpaths in the protection zone covering the two infected farms would be closed immediately.
Cranes piled cattle carcasses onto trucks and authorities expanded the protection zone around a second farm Tuesday, scrambling to halt the spread of the highly contagious virus to other herds in southern England.
The new cull and the slight expansion of the surveillance zone took place after a second group of cows were confirmed with the disease. Both farms, about 30 miles southwest of London, were within the initial two-mile-radius protection zone set up Friday, Benn said.
Prime Minister Gordon Brown said a second report was expected as early as Wednesday
"The work goes on to isolate, to contain, control and eradicate the disease," Brown said after the initial report was published.
The health and safety agency said Merial should not immediately resume production, despite a pending government order for 300,000 doses of a strain-specific foot-and-mouth vaccine.
"Our assessment is that there is no reason to prevent the Institute for Animal Health from operating providing that all the usual biosecurity protocols are followed rigorously. In relation to Merial, we advise that further work be done before any operations involving live pathogens are restarted," the health and safety agency's chief executive Geoffrey Podger said.
Merial had previously said it found no evidence of a breach in biosecurity, and the IAH claimed a check of records found "limited use" of the virus in the past four weeks.
Roger Pride, who runs the farm near Godalming, southern England, where the first outbreak was confirmed, said Tuesday his staff realized there was a problem when they spotted the cattle were "off color and drooling."
"For a moment we couldn't believe it. We were completely shocked and devastated," he said. "It felt as if our whole world was turned upside-down."
News of a second confirmed outbreak fed fears of a repeat of scenes in 2001, when 7 million animals were culled and incinerated on pyres, devastating agriculture and rural tourism in Britain.
"We were starting to think this virus had been contained and maybe we were going to be getting back to normality in a few weeks," farmer Laurence Matthews, who owns the farm where the second infected herd grazed, told British Broadcasting Corp. radio Tuesday.
"Now this has set us back again and most farmers, and I've been speaking to a few, are very, very scared," he said. Matthews, who met Prime Minister Gordon Brown when the leader toured the region Monday, said the infected cows belonged to a fellow farmer who used his land.
The containment process seemed slow and laborious, as tractors, glimpsed from behind a thick row of trees, haphazardly piled carcasses. Once the pile was complete, a black crane grabbed the carcasses, one or two at a time, and slid them gently, but quickly, into a truck that would haul them off the premises
Britain's Chief Veterinary Officer Debby Reynolds has said the strain found in the first herd matched samples taken during Britain's 1967 outbreak of foot-and-mouth disease. The strain had not been seen in animals for a long time, but was used to produce vaccines, she said.
Foot-and-mouth disease affects cloven-hoofed animals, including cows, sheep, pigs and goats, but does not typically affect humans.
The Department for the Environment, Food and Rural Affairs said a total of 199 cows have been culled.
Britain has banned the export of livestock, meat and milk, a decision endorsed by the European Commission.
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