Table 4.
Global model inputs that do not vary between blocks, characterization of oSIAs, and characterization of non-cVDPV risks and potential polio antiviral drug use
| Model input | Value |
|---|---|
| Age groups | 0-2, 3–11 months; 1–4, 5–9, 10–14, 15-39a; ≥ 40 yearsa |
| Number of equally-sized subpopulations per block | 10 |
| Proportion of children receiving fewer than 3 non-birth RI doses who receive 1 non-birth dose | 0.2 |
| Proportion of children receiving fewer than 3 non-birth RI doses who receive 2 non-birth doses | 0.2 |
| Relative coverage with birth dose compared to non-birth RI coverage with 3 doses | |
| - LOW, LMI blocks that use OPV-only at T0 | 0.5 |
| - All other blocks | 0 |
| Average per-dose take rate for IPV | |
| - LOW, LMI | 0.63 |
| - UMI | 0.70 |
| - HIGH | 0.75 |
| Duration of each SIA (days) | 5 |
| Number of oSIA rounds | |
| - Before homotypic OPV cessation | 3 |
| - After homotypic OPV cessation, R0 < 12 | 4 |
| - After homotypic OPV cessation, R0 ≥ 12 | 6 |
| Geographical scope of oSIAs | |
| - Before homotypic OPV cessation | Subpopulation |
| - After homotypic OPV cessation, R0 < 10 | Subpopulation |
| - After homotypic OPV cessation, R0 ≥ 10 | Block |
| Target age groups | Cohorts born since OPV cessation, rounded to next multiple of 5 |
| oSIA impact | |
| - True coverage | 0.8 |
| - Repeated missed probability | 0.7 |
| Time from outbreak detection until the first oSIA (days)b | |
| - No ongoing outbreak response in block | 45 |
| - Outbreak response already ongoing in block | 30 |
| Interval between oSIA rounds (days) | 30 |
| Number of years when mOPV allowed for oSIAs after OPV cessation of each type (years) | 5 |
| Exportation threshold (E *, i.e., cumulative effective infections needed to trigger a potential exportation from a subpopulation) | 200,000 |
| Proportion of virus exportations | |
| - within the same block | 0.960 |
| - in another block within the same region | 0.035 |
| - outside of the region | 0.005 |
| Characterization of post-OPV cessation risks (non-cVDPV) | |
| Average time between contacts of long-term iVDPV excretors with the general population (days) | 150-600 |
| Global Poisson ratec for release of unreturned OPV (only during first year after OPV cessation of each type and in blocks that use OPV at T0) (1/year) | 0.1 |
| Global Poisson ratec for release from IPV production site (1/year) | 0.2 |
| Global Poisson ratec for other unintentional or intentional release (1/year) | 0.025 |
| Probability that other unintentional or intentional release is unintentional | 0.5 |
| Distribution of unintentional releases by income level | |
| - LOW | 0 |
| - LMI | 0.01 |
| - UMI | 0.09 |
| - HIGH | 0.90 |
| Distribution of intentional releases by income level | |
| - LOW, LMI, UMI | 0.5 |
| - HIGH | 0.5 |
| Characterization of impacts of PAVDs | |
| Proportion of long-term iVDPV excretors who had VAPP that receive PAVDs | |
| - No PAVDs (base case) | 0 |
| - PAVD40% | 0.5 |
| - PAVD90% | 0.9 |
| Proportion of asymptomatic long-term iVDPV excretors that receive PAVDs | |
| - No PAVDs (base case) | 0 |
| - PAVD40% | 0 |
| - PAVD90% | 0.9 |
| Proportion of long-term iVDPV excretors receiving PAVDs who recover | |
| - PAVD40% | 0.4 |
| - PAVD90% | 0.9 |
Abbreviations: cVDPV, circulating vaccine-derived poliovirus; HIGH, high-income; IPV, inactivated poliovirus vaccine; iVDPV, immunodeficiency-associated vaccine-derived poliovirus; LMI, lower middle-income; LOW, low-income country; OPV, oral poliovirus vaccine; oSIA, outbreak response SIA; PAVD(40 %, 90 %), polio antiviral drug (passive or active use policy, respectively); R0, basic reproduction number for serotype 1 wild poliovirus; RI, routine immunization; T0, beginning of analytical time horizon (i.e., January 1, 2013); SIA, supplemental immunization activity; UMI, upper middle-income
a Age groups impacting the fraction of newborns born as maternally immune children [47,52]
b Detection of paralytic cases assumes a time of 10 days between onset of infection and paralysis to reflect the average incubation period [47]
c Global Poisson rates indicate the baseline annual rate at which potential introduction events occur anywhere in the world, with the distribution by income level indicated separately or as indicated in the text for IPV production site releases