LONDON, Aug. 7 — There is a “strong probability” that the outbreak of foot-and-mouth disease in Britain was caused by viruses that escaped somehow from a pair of veterinary laboratories where vaccines are made, a government report said today.
The disease was found in cattle on a second farm in southern England today, and 102 animals from that farm were slaughtered, British agricultural officials said.
That farm, and the first farm where the disease was confirmed, are both within a few miles of the laboratories, the government-run Institute of Animal Health and Merial Animal Health, a commercial facility run by a subsidiary of Merck & Co., the American pharmaceutical maker.
The report, issued by the British government’s Health and Safety Executive, found a “negligible” chance that the virus had been released from the labs by becoming airborne, or that recent flooding in the area had led to the release. Human movement or waterborne release unrelated to the flooding remained possibilities and were still being investigated, the report said.
The new herd of 102 infected cattle were within a six-mile “protection zone” that was established after the first cases of foot-and-mouth, a highly contagious viral disease, were confirmed last Friday at a farm in Guildford, Surrey, about 30 miles southwest of London and about 4 miles from the labs. The European Union banned imports of livestock from Britain over the weekend because of the outbreak.
Despite the discovery of a second farm with the disease, authorities appeared to be relieved that it was geographically close to the first one.
Laurence Matthews, the farmer who owns the land where the second outbreak was found, said his family was “absolutely devastated.” Mr. Matthews told BBC radio: “We were starting to think that maybe this virus had been contained. Most farmers are very, very scared, and all activity on farms has almost come to a standstill.”
The two labs were identified by the Minister of Environment, Hilary Benn, over the weekend as a possible source of the outbreak. Officials said then that the strain of the virus found in the cattle at Guildford matched one used at the facilities.
Both laboratoriues denied that there had been any breaches in their biosecurity procedures.
As the investigation into the outbreak continued, the British farming industry debated whether it would be necessary for farmers to start vaccinating their livestock against foot-and-mouth disease, a move that has been resisted over the years. Vaccinating the livestock would immediately cost Britain its designation as a foot-and-mouth-free country and hamper its exports.
Agricultural experts said that even if small numbers of animals were vaccinated, Britain would be unable to export meat or livestock to non-European Union nations for six months.
The European Union’s ban on British livestock imports, formalized on Monday, includes all live animals, including cattle, sheep, goats and pigs, as well as all fresh milk and meat, which can transmit the virus. The disease can also attack various species of wildlife including deer; it very rarely affects humans.
Britain’s Meat and Livestock Commission said the country’s cattle and beef exports in 2006 were valued at £100 million (about $200 million at current exchange rates).
Prime Minister Gordon Brown, who canceled his summer vacation to take charge of the response to the foot-and-mouth-disease outbreak, received unusually high marks from the British news media for quick action.
The last time the disease broke out in Britain, in 2001, the Blair government waited three days before imposing a ban on the movement of livestock around the country, a delay that could have helped spread the virus, a government report said later.
The conclusions of that report — especially the recommendation to shut down the transportation of animals and to quickly destroy infected livestock — have helped propel Mr. Brown’s actions this time.