Neglected, leaky pipes and England's record-setting wet summer likely combined to cause the country's recent outbreak of foot-and-mouth disease (FMD), according to two reports issued on Friday. The virus probably escaped from a company, Merial, that grew vast amounts of it for vaccine production, the studies say. Yet the reports assign most of the blame for the outbreak to the Institute for Animal Health (IAH), a government lab at the same site in Pirbright that owned the aging network of underground wastewater pipes. IAH appears to have breached biosecurity in other ways as well.
Rapid government action helped contain the outbreak, first confirmed on 3 August, to just two farms in Surrey (ScienceNOW, 6 August). Still, the National Farmers' Union puts the accident's economic impact at more than $100 million, and some politicians have called for resignations at the Department for Environment, Food and Rural Affairs (Defra), which oversees biosafety at IAH and also funds two-thirds of its work.
Genomic comparisons of the outbreak virus to strains from Merial and IAH can't pinpoint from which of the two labs the virus escaped, according to the reports, one led by the U.K.'s Health and Safety Executive (HSE), a government agency, and the other by Imperial College London molecular epidemiologist Brian Spratt. Still, the panels say, it's more likely that the virus came from Merial, which grew it in two 6000-liter vats shortly before the accident, producing a million times more virus than IAH used in its small-scale experiments.
But the virus probably escaped through leaks in a complex system of pipes. Those pipes take the water to a shared effluent treatment plant, managed by IAH, where caustic soda is used to raise the pH to 12 and kill off any remaining virus during a 12-hour holding period. The reports hypothesize that live virus seeped into the soil as a result, especially as July's excessive rainfall may have caused the drains to overflow. As it happened, construction crews were digging holes around the leaks at the time, and heavy trucks--without proper IAH oversight--drove through the presumably virus-laden mud. Some of these vehicles later took a road that went very close to the first infected farm. From there, the farmer may have carried the virus to his herd.
IAH, a part of the U.K. Biotechnology and Biological Sciences Research Council (BBSRC), owns the antiquated drainage system, the HSE report says. It was also aware of some of the network's problems. In fact, IAH, Defra, BBSRC, and Merial had debated an upgrade since 2003; the problem was money. The findings are a blow to the reputation of IAH, a world-renowned FMD research center, says Andrew Mathieson, an environmental health expert at the University of the West of England in Bristol. But they should also serve as a more general warning. "My worry is: What about the many other research establishments of the same age?" he says.
Defra says it will adopt a range of recommendations to fix problems at Pirbright, such as keeping better track of visitors and making sure biosafety officers communicate. IAH, which was constructed in 1924, is due to be almost completely rebuilt by 2012, although some funding issues remain.