polio vaccine Health Bill and Melinda Gates to pay off Nigeria’s $76 million polio debt Nigeria, which accounted for more than half of all polio cases in 2012, reported zero new cases of the infectious disease in 2017.
Health Bill and Melinda Gates to pay off Nigeria’s $76 million polio debt Nigeria, which accounted for more than half of all polio cases in 2012, reported zero new cases of the infectious disease in 2017.
