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A railroad worker wears protective gear inside a train during a drill on preventing the H5N1 virus in Hong Kong February 5. Health experts fear the virus could spark a deadly pandemic if it mutates into a form that passes easily from person to person.

Railroad workers in protective gear walk on the platform during the drill on preventing the H5N1 virus.

A railroad worker in protective gear covers a mock bird inside a train.

(China Daily February 6, 2007)