TO GO WITH AFP STORY BY AMINU ABUBAKAR A polio vaccinator administers oral drops to a child in the Dawanau district of Kano, northern Nigera, on October 28, 2013 during a polio immunisation campaign in six local government areas found to harbour polio virus. Bill and Melinda Gates Foundation is funding a hi-tech electronic tracking of vaccination in eight high-risk states in the region as part of global effort to eradicate polio. US billionaire Bill Gates on November 11 vowed to help end the scourge of polio in Nigeria, Africa's most populous nation, still blighted by the debilitating disease. AFP PHOTO / AMINU ABUBAKAR / AFP / AMINU ABUBAKAR (Photo credit should read AMINU ABUBAKAR/AFP/Getty Images)
