“…Nigeria is one of three countries, including Pakistan and Afghanistan, where wild poliovirus (WPV) transmission has never been interrupted. In September 2015, after >1 year without any reported WPV cases, Nigeria was removed from WHO’s list of countries with endemic WPV transmission ( 2 ); however, during August and September 2016, four type 1 WPV (WPV1) cases were reported from Borno State, a state in northeastern Nigeria experiencing a violent insurgency ( 3 ). The Nigerian government, in collaboration with partners, launched a large-scale coordinated response to the outbreak ( 3 ).…”