Aug 17, 2007 (CIDRAP News) – As British veterinary officials continued to investigate outbreaks of food-and-mouth disease (FMD) at two farms this week, worries about possible outbreaks at two other sites in England were dispelled.
Animal handlers at a farm in Kent and a zoo in Surrey reported suspicious lesions in animals, but test results were negative, and the government eased restrictions on livestock movements in those areas.
The United Kingdom's chief veterinary officer, Debby Reynolds, said on Aug 15 that the risk that FMD would spread beyond the original affected area was "very low," according to an Aug 15 Reuters report.
FMD outbreaks were confirmed in early August on two farms about 30 miles southwest of London, in Surrey. Officials said the outbreaks were probably linked to a leak from a laboratory in nearby Pirbright that houses a commercial vaccine producer and a government-funded research institute.
Both organizations have denied there were any lapses in their biosecurity procedures, according to a recent Agence-France Presse (AFP) report.
More than 570 animals were destroyed to control the spread of the disease, Reuters reported on Aug 15.
The two sites that sparked the latest worries are outside the original protection zones surrounding the two infected farms. At the Kent location, a farmer had reported suspicious lesions on the muzzles of his calves, the AFP report said. In Surrey, officials at a zoo called Chessington World of Adventures had reported that a sheep showed symptoms of the disease, AFP reported. In response, veterinary officials placed 3-km control zones around the sites.
Reynolds lifted temporary restrictions in the areas Aug 15 after final results showed the animals didn't have the disease, according to a statement from the UK Department for Environment, Food, and Rural Affairs (DEFRA). She also said that vaccination teams, which stood ready for activation, would not be needed.
According to DEFRA's most recent epidemiologic report on the FMD outbreak, the outbreak strain of virus has been identified as type O1 BFS, the same strain recovered from a 1967 FMD outbreak in Britain. "This strain is used by both of the enterprises on the nearby Pirbright site. Current evidence indicates that this site is the likely source of infection for the outbreak," the report said.
Investigators were still trying to determine how the pathogen spread to the farms and are focusing on escape by contaminated flood water or contaminated items such as clothing, equipment, or vehicles, the report said.
The FMD outbreak is Britain's first since 2001, when authorities destroyed 7 million cattle to contain the disease. A European Union export ban on British meat and livestock is in effect through Aug 25, but leaders will meet on Aug 23 to consider easing the ban, AFP reported.
Aug 7 CIDRAP News story "Report: Lab leak likely caused UK food-and-mouth outbreak"