The National Association of Agricultural Contractors is urging operators to take every possible biosecurity precaution and avoid visiting stock farms, where possible.

Operations such as contract shearing, dipping and sheep-scanning are currently prohibited until a licensing system can be established.

DEFRA insists that all livestock contractors – including foot-trimmers, cattle-scanners and AI specialists – should stay away from farms for now.

Forage-harvesting and muck-spreading are also restricted in the protection and surveillance zones that surround the infected area in Surrey.

The NAAC advises that contractors should contact customers before visiting any farm and ensure all vehicles, equipment and staff are disinfected on entering and leaving any premises.