Since early 2006, highly pathogenic avian influenza H5N1 has been clocking up air miles at an alarming rate. It has spread quickly,to Europe, the middle east, India, and Africa following noapparentpattern,andunderlining how little scientists know about the virus ecology and where it will strike next. There is now growing concern that the whirlwind spread of avian flu in some parts of the world is not entirely governed by nature, but by the human activities of commerce and trade.
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