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A child receives an oral polio vaccine on June 25, 2011 in the Abobo suburb of Abidjan during the opening of the second national day of polio vaccinations organised by the World Health Organisation, UNICEF and Rotary International among others. AFP PHOTO / ISSOUF SANOGO (Photo credit should read ISSOUF SANOGO/AFP/Getty Images)

A child receives an oral polio vaccine on June 25, 2011 in the Abobo suburb of Abidjan during the opening of the second national day of polio vaccinations organised by the World Health Organisation, UNICEF and Rotary International among others. AFP PHOTO / ISSOUF SANOGO (Photo credit should read ISSOUF SANOGO/AFP/Getty Images)