WHO's polio fact sheet: wild poliovirus cases down over 99% since 1988 and the African region certified free of wild poliovirus in 2020 — the eradication-program context in which vaccine-derived outbreaks have become the larger share of cases.
wild poliovirus cases have decreased by over 99% since 1988
WHO's polio fact sheet: wild poliovirus cases down over 99% since 1988 and the African region certified free of wild poliovirus in 2020 — the eradication-program context in which vaccine-derived outbreaks have become the larger share of cases. WHO is the program's own lead agency; the fact sheet does not publish a 2020 cVDPV case total, so the comparison rests on the MMWR series (MME-46, MME-47).