Conspiracy theories and urban myths doing the rounds in Britain suggest that everyone from illegal immigrants and animal rights activists to foreign terrorists and vets are responsible for the foot-and-mouth outbreak.
Most of the rumours, such as the one that Saddam Hussein sent an envoy to spray the virus on to animals, are laughable or appear impossible to prove.
Other theories, such as the possibility that illegally imported meat found its way into pig swill which was not properly cooked and then caused the outbreak, are being investigated.
Behind them all, the rumour that foot-and-mouth has been in Britain for months and that the Ministry of Agriculture failed to identify it persists.
The pig farm at Heddon-on-the-Wall in Northumberland, identified by the British government as the possible source of the outbreak, was visited six times by officials from the Ministry of Agriculture, animal health officers and trading standards officers in the year before the outbreak was confirmed.
A vet from the Ministry of Agriculture and an animal health inspector from Northumberland County Council visited Burnside farm, operated by Mr Bobby Waugh and his brother, Ronnie, on December 22nd after complaints were made to the RSPCA about the conditions in which animals were being kept.
After the visit the Ministry said the 520 pigs on the farm were "fit and healthy", although a notice warning was served on the Waughs to improve conditions.
However, one animal welfare officer has suggested that the pigs may already have been incubating foot-and-mouth when Ministry of Agriculture officials visited the farm, and that they failed to notice it.
"It is absolutely crucial that we see the reports into the visits to the farm. It is in the public interest that the reports are published," Mr Martin Coutts, an animal welfare officer with the Norwich-based Hillside Animal Sanctuary, told The Irish Times.
On December 16th, Mr Coutts says, he received a report from a person who had worked on Burnside farm alleging poor farming practices. The RSPCA notified Northumberland County Council, which investigated. The December 22nd visit found the animals in a "satisfactory condition", the county council said.
A follow-up visit by a Ministry vet and animal health officials from the county council on January 24th again found conditions were satisfactory.
However, the Agriculture Minister, Mr Nick Brown, has accepted that soon after the visit pigs on the farm may have developed foot-and-mouth.
The Waughs have consistently denied allegations of poor farming practices. In a statement on February 25th, Mr Bobby Waugh said: "I honestly had not seen anything wrong with any of the pigs in the last few weeks."
This week he criticised Mr Brown for being "judge and jury" and said his holding was being wrongly targeted. "I've been made a convict and I haven't even been given a chance to reply," he told the Guardian.
The Ministry of Agriculture said the results of its investigation into the source of the disease, and an investigation by Northumberland County Council into the outbreak in its region, could not be made public because they might "prejudice" any possible legal action.
A Ministry official said: "It wasn't in our interests to be aware of a disease and not to let people know about it. It simply doesn't make sense."
But Mr Coutts is adamant that the Ministry could have done more to identify the early signs of foot-and-mouth.