Just five days later, the disease was back. Last Wednesday (September 12) the disease was confirmed in cattle grazing at Milton Park Farm, near Egham, in Surrey – about 14 miles away from the site of the August outbreaks, and outside the previous Surveillance Zone.

Then on Friday, disease was confirmed in cattle at the neighbouring Stroude Farm, after about 50 cattle and 900 pigs had been slaughtered on suspicion.

The next outbreak – the fifth since August 3 – was confirmed on Tuesday in a small herd of about 20 cattle at the Klondyke, next to Stroude Farm and inside the 3km Protection Zone. Their flock of about 20 sheep had been exposed to the virus but disease was not confirmed in sheep as FG went to press.

But how did the virus – not seen anywhere since early August – suddenly reappear?

The answer to this is crucial to establishing the level of risk facing farmers in Surrey, and the rest of the country. Yet by Wednesday, Defra appeared to have no firm idea as how the virus got to the Egham area.

Source: Farmers Guardian