Vaccine-Derived Polioviruses, Central African Republic, 2019

Abstract Since May 2019, the Central African Republic has experienced a poliomyelitis outbreak caused by type 2 vaccine-derived polioviruses (VDPV-2s). The affected Bangui, capital city, and 10 districts across country. resulted from several independent emergence events of VDPV-2s featuring recombinant genomes with complex mosaic genomes. low number mutations (<20) in viral capsid protein 1–encoding region compared vaccine strain suggests that VDPV-2 had been circulating for relatively short time (probably <3 years) before being isolated. Environmental surveillance, which relies on limited sampling sites does not cover whole country, failed to detect circulation some induced children.