In China, a deadly strain of bird flu now easily infects ducks
A vaccine that protects chickens from the virus works in ducks, too

DUCK FLU Some ducks in China’s Fujian province carry highly pathogenic strains of the H7N9 avian influenza virus. The ducks shown here were photographed on a farm in Fujian province in April 2013, three years before the high pathogenicity strains emerged.
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