Disease reached Britain a fortnight ago, say scientists

Scientists suspect foot-and-mouth disease reached Britain through food discarded from a docking container ship and fed to pigs up to a fortnight ago. They are trying to find why neither the farmer nor the vet on the farm identified as "ground zero" in the outbreak immediately spotted the signs of infection, specifically blisters on animals' mouths and legs.

Scientists suspect foot-and-mouth disease reached Britain through food discarded from a docking container ship and fed to pigs up to a fortnight ago. They are trying to find why neither the farmer nor the vet on the farm identified as "ground zero" in the outbreak immediately spotted the signs of infection, specifically blisters on animals' mouths and legs.

A team at the Institute of Animal Health, in Pirbright, Surrey, will work around the clock this weekend studying blood samples from every animal on the farm at Heddon-on-the-Wall near Newcastle, pinpointed as the source of the outbreak that has crippled the farming industry.

Paul Kitching, a world expert in the disease, was at the farm yesterday with a specialist group to examine pigs and other livestock for signs of old or healed blisters from the illness. "They have gone on behalf of the Ministry [of Agriculture, Fisheries and Food] to give their best opinion," said Alex Donaldson, the head of the institute. "They're trying to work out how long the infection has been there, and what risk there might be to the surrounding area."

Some of the animals on the farm are understood to have high levels in their blood of antibodies to the virus, a sign that they have been infected and fought off the illness. "That takes at least four to five days," said Dr Donaldson. "There is also the incubation period before the disease actually starts to affect an animal. Taking all those factors together, that means this disease has been in the country for one week at the absolute minimum."

Though the exact source was still a mystery, Dr Kitching's team established earlier this week that the virus is a strain that originated in India, and has been seen in South Korea and Japan in the past year. "The next question, once we've established when it got to the farm, is how it got there," said Dr Donaldson. "Other incidents have been attributed to garbage from ships being given to pigs uncooked." The outbreak last year of swine fever, also an Asian strain, came from a sandwich thrown to a pig on a farm.

Jim Scudamore, the chief veterinary officer, said the farm at Heddon-on-the-Wall, Tyne and Wear, was the source of the Essex cluster of outbreaks and two farms and an abattoir have been sealed off after the disease was confirmed there. "We have had active disease in the country for longer than we had thought, and that could have been spreading," he said.

The Pirbright team will bring back "scores" of samples from every animal on the Heddon farm for DNA examination. "We don't have a mobile laboratory, because that would increase the chance of spreading infection by carrying it around on tyres and so on," said Dr Donaldson.

But he was surprised the infection had not been spotted sooner. "Foot-and-mouth disease can stay quiescent if people don't report it," he said. But the highly infectious nature of the disease means that if it was not reported for even a couple of days after an animal fell ill, farms and land in the area could be infected.

Craig Kirby, the vet who discovered the sick animals at an Essex abattoir, said: "We had pigs and sows on site ready for slaughter. As is normal, the pigs were dealt with first, and gave me no cause for concern.

"The drover began moving the sows, and they became very noisy. I moved in to look at their condition. They were showing signs of foot-and-mouth.

"It is not a disease I have seen before, but it is one of the key diseases we are trained to spot. The implications of missing an outbreak of foot-and-mouth at an early stage are enormous, given how far and how fast it travels.

"I have always hoped never to see it, for the sake of the livelihoods of farmers; others in the industry, and the well-being of the animals."