THE confirmation of a bird flu outbreak in Dorset has sent shock-waves through local communities.

News that three dead swans at Abbotsbury had been found carrying the deadly H5N1 strain, is the last thing farmers, tourist chiefs and poultry owners wanted to hear.

Thursday's discovery comes less than a month after restrictions on poultry movement were lifted in Norfolk and Suffolk.

The restriction zone was imposed following an outbreak of H5N1 on a free range turkey farm in November and only removed on December 19.

Thousands of birds on six premises were culled in the wake of the outbreak, which Defra said had been contained to two farms in Suffolk.

In a preliminary report into the outbreak, Defra said wild birds could not be ruled out as a source of infection.

Thursday's shock discovery in the Chesil Beach area is the second H5N1 avian influenza case detected in a wild bird in the British Isles.

The previous case, also involving a swan, was confirmed in Cellardyke, Fife in April 2006.

As fears grew of a bird flu epidemic, following the discovery of an infected swan, Dorset residents dialled the emergency services at the mere sighting of a dead sparrow.

Dorset police wildlife officer PC John Snellin advised people not to touch dead birds but contact Defra if a swan, goose or group of birds were involved.

He said: "Bird flu doesn't affect all birds - it's really just waterfowl such as swans and geese."

Avian influenza is a disease of birds. While it can pass very rarely and with difficulty to humans, this usually requires extremely close contact with infected birds, particularly faeces.

If the virus gained the ability to pass easily between humans the results could be "catastrophic", scientists have claimed.

Should it mutate, experts predict anything between two million and 50 million deaths.

Symptoms in humans are similar to other types of flu and may include a fever or cough, shortness of breath, headache, sore eyes, muscle aches or a sore throat. People cannot be affected by properly cooked poultry.

H5N1 claimed its first human victim; a three-year-old boy, in Hong Kong in May 1997.

Since being detected again in February 2003, it has spread west through Asia, the Middle East, Europe and Africa, despite mass bird culls and exclusion zones.

According to figures from the World Health Organisation there have been 335 confirmed cases of H5N1 in humans, leading to 206 deaths.

Advice from the Food Standards Agency remains that property cooked poultry and poultry products, including eggs, are safe to eat.

Local councils have contingency plans in the event of an outbreak of bird flu in their area.

Ian Johnson, South West spokesman for the National Farmers' Union, said: "After the last 12 months of plague and pestilence, this is the last thing on God's green earth we would have wished for.

"We have got to deal with it expediently but there is no need to panic as it appears to have been contained.

"Vigilance is important amongst poultry keepers but, given a fair wind and co-operation in minding the controls, there is no reason to believe it is anything but an isolated yet regrettable outbreak and we are working very closely with Defra."

West Dorset MP Oliver Letwin, whose constituency includes the swannery, said: "Obviously this is very worrying for poultry farmers and others but I am glad to see it is being treated with the seriousness it deserves.

"I very much hope we will get through this with the swannery intact, because it is a remarkable national institution of real beauty and real ecological significance."