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An Indian boy receives a polio vaccination from an Indian health worker in Amritsar last year. Narinder Nanu/AFP/Getty Images hide caption
A woman, left, cuts the hair of a fellow tuberculosis patient at a clinic in the township of Khayelitsha, on the outskirts of Cape Town, South Africa, in March.
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A street scene in New York City on Tuesday (May 31, 2011). Spencer Platt/Getty Images hide caption