Nigeria records first vaccine-derived polio case since 2014
Report does not affect nation’s free virus status
Despite recording the first case of type 2 circulating vaccine-derived poliovirus (cVDPV2) in Maiduguri district of Borno province, Nigeria is on course towards being certified polio- free by the World Health Organisation (WHO) after July 2017.
And in response to this outbreak, Nigeria is planning to conduct the first ever campaign using monovalent oral polio vaccine type 2 even as the Director General of the WHO has authorized the vaccine release from the global stockpile.
Sub-National Immunization Days (SNIDs) are planned in the north of the country from May 14 to 17 using bOPV.
Nigeria alongside 154 other countries have completed the switch from trivalent oral polio vaccine (tOPV) to bivalent oral polio vaccine (bOPV), withdrawing the type two component of the vaccine to protect future generations against circulating vaccine derived polioviruses, which held from April 17 to May 1.
According to the latest edition of Weekly Polio Update published yesterday by the Global Polio Eradication Initiative (GPEI), “No wild poliovirus type 1 (WPV1) cases have been reported in 2016. No cases were reported in 2015. The most recent case had onset of paralysis on 24 July 2014 in Sumaila Local Government Area (LGA), southern Kano State.
“One environmental sample positive for cVDPV2 was reported this week, collected in Maiduguri district of Borno province on 23 March 2016.
“Genetic sequencing of the isolated strain indicates it is most closely linked genetically to a cVDPV2 strain from Borno in November 2013 and last detected in May 2014, indicating the strain has been circulating without detection for almost two years.’’