Table 4.
Implications of intensification versus maintenance in terms of indigenous cVDPV outbreaks and vulnerability to WPV or cVDPV importations.
| Population with properties like | Indigenous cVDPV1 outbreaks before/after OPV13 cessation | Indigenous cVDPV3 outbreaks before/after OPV13 cessation | Percent of time during 2017–2019 with Rn>1 for cVDPV1 | Percent of time during 2017–2019 with Rn>1 for cVDPV3 | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ia | M1b | M3c | I | M1 | M3 | I | M1 | M3 | I | M1 | M3 | |
| Northern India, general | None | None | None | None | None | None | 88 | 63 | 44 | 70 | 40 | 0 |
| Northern India, under-vaccinated | Before | None | None | None | None | None | NAd | 91 | 60 | 94e | 67 | 25 |
| Northern Pakistan and Afghanistan, general | None | None | None | None | None | None | 59 | 28 | 0 | 38 | 0 | 0 |
| Northern Pakistan and Afghanistan, under-vaccinated | Before | After | After | Before | None | None | NAd | 100 | 100 | 97e | 97 | 86 |
| Northern Nigeria, general | None | None | None | None | None | None | 64 | 11 | 0 | 35 | 0 | 0 |
| Northern Nigeria, under-vaccinated | Before | After | None | None | None | None | NAd | 100 | 100 | 100e | 100 | 100 |
a
I indicates bOPV intensification consisting of 0 annual bOPV SIAs during 2017–2019 and between 1 and 4 bOPV SIAs in 2020 prior to OPV13 cessation
b
M1 indicates bOPV maintenance consisting of 1 annual bOPV SIA during 2017–2020
c
M3 indicates bOPV maintenance consisting of 3 annual bOPV SIA during 2017–2020
d
Not applicable: Indigenous cVDPV outbreak prior to OPV13 cessation
e
SIAs in response to indigenous cVDPV 1 outbreak would affect population immunity to serotype 3 transmission