A low severity case of avian flu has been confirmed in chickens at a farm in Hampshire and robust action is being taken to prevent any spread of the disease, which poses very low risk to human health, according to the latest report from the agriculture department, Defra.

Tests have confirmed the outbreak as a low severity H7 strain of the disease, a much less severe form than the H5N8 strain found at a Yorkshire duck farm in November. There are no links between the two cases.

A 1-km poultry movement restriction zone has been imposed and the birds at the commercial chicken breeding farm are being culled as part of our tried and tested procedures for responding swiftly and thoroughly when an outbreak occurs. The cull to prevent the spread of potential infection is being carried out in a safe and humane manner by fully trained APHA staff.

The advice from Public Health England (PHE) is that the risk to public health is very low, and the Food Standards Agency has said there is no food safety risk for consumers.

Chief Vet Nigel Gibbens said: "We have taken immediate action to contain this outbreak as part of our robust procedures for dealing swiftly with avian flu. This is a low severity form of the virus and we are taking action to ensure that the disease does not spread or develop into a more severe form. We are investigating the possible sources of the outbreak.

"I would urge poultry keepers in the surrounding area to be vigilant for any signs of disease and to ensure they are maintaining good biosecurity on their premises."

Professor Nick Phin, Director of PHE’s Centre for Infectious Disease Surveillance and Control said: "Based on what we know about this strain of avian influenza and the actions that have been taken, the risk to human health in this case is considered very low. Public Health England continues to work closely with Defra throughout this investigation."

A spokesperson for the Food Standards Agency said: "On the basis of current scientific evidence, Food Standards Agency advice is that avian (bird) flu does not pose a food safety risk for UK consumers.

"Laboratory investigations on the outbreak indicate that it is the N7 sub-type of H7 but this will need to be confirmed in further testing."

Anyone suspecting avian influenza should immediately contact their nearest Animal and Plant and Health Agency (APHA) office.

Defra has reported the outbreak to the World Organisation for Animal Health (OIE).

That report gives additional information, including that the affected farm is in Upham, near Southampton and that the outbreak started on 29 January in a flock of 10,539 40-week-old housed broiler breeders. Of these, 52 birds died.

The source of infection is unknown, and it is confirmed that the virus is a low-pathogenic H7 subtype.