What's in this vial changes from year to year, but the process of creating the flu vaccine remains pretty constant.

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A Haitian protester in Port-au-Prince last month spray-paints a wall, equating the UN mission in Haiti (abbreviated here as MINISTA) with cholera.

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Paul Keim at work in his lab on the Northern Arizona University campus.

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Victims of the plague are consigned to a communal burial during the Plague of London in 1665.

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