Government investigators are racing to uncover the source of the Suffolk bird flu outbreak which has seen 160,000 turkeys slaughtered in a mass cull expected to end this morning.

Identifying the source of the virus is key to containing its further spread.

Suspicion has naturally fallen on the most recent European appearance of the H5N1 strain in Hungary, which has suffered a cluster of cases in the last month. Bernard Matthews, the food group which owns the Suffolk turkey facility hit by Britain's first confirmed outbreak of the disease, also owns a large Hungarian farming company.

According to The Guardian, a Bernard Matthews spokesman said: "All our birds are British. The fact that we have a Hungarian operation is immaterial. It is very unlikely. It's a complete mystery to us. We have the highest biosafety standards of anyone. We are waiting for Defra to finish its investigations and they will tell us the likely cause."

DEFRA said it would probe the Hungarian connection. It is maintaining an 807 square mile exclusion zone around the farm and is monitoring local wild bird populations, though Japan has already temporarily suspended UK poultry imports.

The arrival of the virus in Britain has long been expected, though vets first suspected E. coli bacteria when birds started dying last week.

H5N1 has killed more than 150 people worldwide since emerging in southern Chinese province Guandong in 1996. All those victims are thought to have had close contact with infected birds. There is no sign yet of the evolutionary jump H5N1 would need to perform for human to human transmission to become a global pandemic similar to the 1918 bird flu, which is estimated to have killed about 18 million.

More here (http://news.bbc.co.uk/1/hi/uk/6330167.stm) at the BBC. ®

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