Notes from the Field: House-to-House Campaign Administration of Inactivated Poliovirus Vaccine — Sokoto State, Nigeria, November 2022

After the 2015 documentation of global eradication of wild poliovirus type 2,* Sabin type 2 oral poliovirus vaccine (OPV) was withdrawn from routine immunization (RI) in all OPV-using countries in 2016, in a global synchronized switch from trivalent OPV (containing vaccine virus serotypes 1, 2, and 3) to bivalent OPV (containing serotypes 1 and 3), to reduce the rare risks for type 2 vaccine-associated paralytic poliomyelitis. In Nigeria’s northwest Sokoto State, outbreak transmission continued even after eight nOPV2 SIAs conducted since March 2021 (National Primary Health Care Development Agency, Polio Expert Review Committee meeting, Abuja, Nigeria, unpublished data, 2023). Because Sokoto reported 27% RI IPV coverage in 2021 (Figure), a campaign to increase IPV coverage was planned. Risk factors for the spread of vaccine-derived type 2 polioviruses after global withdrawal of trivalent oral poliovirus vaccine and the effects of outbreak responses with monovalent vaccine: a retrospective analysis of surveillance data for 51 countries in Africa.