By Guy Faulconbridge
1 hour, 5 minutes agoMOSCOW (Reuters) - Russia said on Tuesday an outbreak of bird flu in Chelyabinsk was dangerous to humans, as teams of sanitary workers destroyed birds in Siberia in an attempt to prevent the westward spread of the deadly virus.
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Russia is battling to contain a bird flu outbreak, which top health officials say has killed more than 11,000 birds countrywide and could spread westwards to Europe, the Middle East and Africa.
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Russian agricultural officials believe the flu was brought by migrating birds from Asia, where more than 50 people have died from the H5N1 strain since 2003. Officials fear that the virus could spread to Europe and Africa as tens of millions of birds continue their migration to warmer climates from next month ahead of Russia's harsh winter.
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Bird flu comes in different strains, such as H5 and H7, which have nine different subtypes. The H5N1 subtype is highly pathogenic and can be passed from birds to humans, though there have been no cases of human to human transmission.