Vaccine-Derived Polioviruses, Central African Republic, 2019

Marie-Line Joffret (1) , Joël Wilfried Doté (2) , Nicksy Gumede (3) , Marco Vignuzzi (1) , Maël Bessaud (1) , Ionela Gouandjika-Vasilache (2)

1 Populations virales et Pathogenèse - Viral Populations and Pathogenesis
2 Institut Pasteur de Bangui
3 WHO, Regional Office for Africa [Brazzaville, Republic of the Congo]

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

Mots clés: Central African Republic; Poliovirus; eradication; oral polio vaccine; poliomyelitis; vaccine-derived poliovirus; viruses

Domaines: Virologie

Marie-Line Joffret, Joël Wilfried Doté, Nicksy Gumede, Marco Vignuzzi, Maël Bessaud, et al.. Vaccine-Derived Polioviruses, Central African Republic, 2019. Emerging Infectious Diseases, 2021, 27 (2), pp.620-623. ⟨10.3201/eid2702.203173⟩. ⟨pasteur-03122581⟩