Table 1.
Evolution of published estimates of the probability of success (POS) of OPV cessation.
| Metric | Time Horizon [IC] | Type, POS a (Range) | Date(s) [Sources(s)] |
|---|---|---|---|
| Pre-OPV2 cessation studies (assumed OPV2 cessation would occur in 2016, bOPV cessation 2019) | |||
| OPV restart | 2013–2052 [End 2014 b] | All types, 98% (90–98%) | 24 Sep 2015 [23] |
| 24 Mar 2016 [21] | |||
| OPV restart | 2013–2052 [End 2014 b] | All types, 94.3% (15–94.3%) | 23 Sep 2016 [64] |
| 1 Jun 2017 [65] (range) | |||
| Post-OPV2 cessation studies (OPV2 implemented in 2016; see text for assumptions for bOPV cessation) | |||
| OPV restart | 2019–2029 [End 2019] | Type 2, 11% (11–56%) | 6 Jul 2020 [28] |
| OPV restart | 2019–2029 [End 2019] | Type 2, 11% (33–78%) | 10 Nov 2020 [59] |
| OPV restart | 2019–2029 c [End 2019] | Type 2, 11% | 19 Feb 2021 [70] |
| Type 1; 2; 3 c 80%; 56%; 100% | |||
| OPV restart | 2019–2023 d [End 2019] | Type 2, 67% (62–73%) | 27 Apr 2021 [60] |
| OPV restart | 2019–2023 d [End 2020] | Type 2, 67% (46–67%) | 14 May 2021 [61] |
| p(die out) | 2022–2026 d [End 2021] | Type 2, <1% (<1–95%) | 17 Nov 2022 [62] |
| p(die out) | 2022–2035 [End 2021] | Type 1; 2 <1; <1% | 21 Jun 2023 [48,49] |
| 14 Aug 2023 [73] | |||
Abbreviations: bOPV, bivalent OPV; GPEI, Global Polio Eradication Initiative; IC, initial conditions; OPV, oral poliovirus vaccine; OPV2, type 2 OPV; p(die out), probability of die out of transmission by the end of the time horizon; POS, probability of successful OPV cessation; pSIA, preventive supplemental immunization activity; WPV1, type 1 wild poliovirus. a Column shows the poliovirus type(s) of POS estimates in the study and the expected POS for the modeled baseline (range of POS values for different scenarios considered, where applicable); see each study for specific details. b Model prospectively assumed GPEI and countries would implement all recommended OPV cessation risk management strategies. c For this study, baseline estimate POS of 11% for type 2, but hypothetical additional scenarios included pSIAs to achieve WPV1 eradication by 2023 and implemented bOPV cessation in 2025 with POS estimates for each type shown. d No consideration of bOPV cessation in this analysis since it would only potentially occur after the model time horizon.