Scientists seek answers as virus spreads

Society Materials 17 September 2007 06:49 (UTC +04:00)

( BBC ) - With two more cases of foot-and-mouth disease found in Surrey this month, following last month's outbreak there, scientists are trying to find out how the disease has spread.

There have been four confirmed cases of foot-and-mouth in the most recent outbreak - the first two were at the beginning of August, at Pirbright, and then on Wednesday this week, a third case was confirmed near Egham, with a fourth on Friday.

Tests have confirmed that the first three are the same strain of the disease. An official report blamed the outbreak earlier in the year on a leak from a government laboratory complex at Pirbright.

There has been no confirmation yet of the origin of the fourth case, but the animals have already been culled.

They were confirmed as high risk contacts - animals that, for example, were in the same field or neighbouring field as infected cattle.

Farming community

Vets are trying to establish how the disease, which is supposed to have an incubation period of only a couple of weeks, has managed to hang around so long.

Several theories are being investigated. Firstly, the possibility that the disease might have been in the cattle in the third outbreak for some time, which would allow a closer link between that and the first two outbreaks.

This is complicated in Surrey by the nature of the farming community there.

Unlike other areas, the farming landscape is fragmented. Fields and farms lie between housing developments, and often one farmer can own several non adjacent fields.

Secondly, that the outbreak has been spread in sheep. It is often impossible to diagnose the disease in sheep, even for experienced vets.

Thirdly, that it has managed to stay in the environment, in some suitable area. In the right cool, dark, neutral conditions, scientists say the disease can live for several weeks.

National differences

One small crumb of comfort is how the outbreak is limited, at present, to Surrey.

Animal health is a devolved issue, and in Wales and Scotland the respective agriculture ministers have made the decision to ease restrictions to allow animals to move off farms, straight to abattoirs for slaughter.

The Scottish Rural Affairs Minister, Richard Lochhead, has now decided to allow farm-to-farm movements for animals from the Scottish islands to the mainland, as this is the busiest time of the farming year - but, he says, he's nowhere near easing restrictions which would allow hill farmers to take their animals to market at what is one of the busiest times of the livestock farmer's year.

Hill farm pressure

"We have a huge sheep sector that's hugely important to the country, and it's on the brink," he told BBC News website.

"In the next few weeks we'll know more as to scale of long-term damage to the industry: 1.1 million sheep have to come off the hills in the next four weeks. Hill farmers in Highlands are in major distress - and it's them, as much as their animals, that I'm concerned about."

English farmers argue that if you live in Cornwall or Northumberland, you're no nearer to the outbreaks in Surrey than Wales or Scotland, and are urging the government's chief vet, Debby Reynolds, to start lifting restrictions region by region, taking the immense pressure off hill farmers in particular.

It's understood that this could happen as early as this weekend.