Health authorities in South Korea, Vietnam and Japan are killing millions of chickens to contain a third outbreak of avian influenza. The highly virulent strain has already claimed the lives of at least five people in Vietnam.
The virus is a variant of the so-called H5N1 virus, which killed six of the 18 people it infected in Hong Kong back in 1997. Experts believe it is present in large amounts, but have not determined which species carry it.
Authorities are watching it closely: the more virus in circulation, the bigger the chance that it could become not just lethal, but highly transmissible.
Reference: Science 303, 447 (2004)
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