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Table 3 Relationship between the time after the switch until the net reproduction number (Rn) of OPV2 (stage 0) virus exceeds 1, the Rn of OPV2 (stage 0) virus at the time of the switch, and population-specific properties based on the populations from the global model [4] represented in the distributions of Fig. 2 (analysis I without tOPV intensification)

From: Implementation of coordinated global serotype 2 oral poliovirus vaccine cessation: risks of potential non-synchronous cessation

Time (years) since switch until Rn of OPV2 > 1 # subpopulations in time range (out of 520 with OPV-only) Properties of subpopulations in range
Average Rn before switcha R0 b poro tr POL3 # tOPV SIA during 2015–2016 TC
1.0–1.45 40 0.41–0.49 12–13 0.3 0.6 0.3 4 0.35
0.6 4 0.8
0.6 4 0.95
0.9 2 0.8
0.98 2 0.95
1.5–1.74 10 0.37–0.44 11 0.3 0.7 0.3 4 0.5
0.6 4 0.8
0.9 2 0.8
0.98 2 0.95
1.75–1.99 30 0.55 8 0.3 0.7 0.05 4 0.15
0.35 9 0.3 0.7 0.6 2 0.8
0.35–0.43 9–12 0.3 0.65–0.7 0.3 4 0.5
0.6 4 0.5–0.95
0.9 2 0.8–0.95
2–2.24 103 0.36–0.41 10–11 0.3 0.65–0.7 0.3 4 0.8
0.6 4 0.8–0.95
0.9 2 0.8–0.95
0.98 0 0.8
2.25–2.49 10 0.37 10 0.3 0.7 0.9 2 0.95
2.5–2.74 18 0.33–0.38 9 0.3 0.65–0.7 0.9 2 0.8
0.98 0 0.95
2.75–3 31 0.26–0.37 7–9 0.3 0.7–0.72 0.3 4 0.5
0.6 2 0.8
0.9 2 0.8
0.98 0 0.8
0.8 0.65 0.6 2 0.95
3–3.99 67 0.25–0.39 7–8 0.3 0.7–0.72 0.3 4 0.8
0.6 2 0.5–0.8
0.9 2 0.8
0.98 0 0.95
0.5 0.72 0.6 2 0.8
0.8   0.9 2 0.95
0.98 0 0.95
0.38c 11 0.3 0.65 0.6 4 0.8
0.53c 11 0.3 0.65 0.1 4 0.35
4–4.99 2 0.29 7 0.5 0.72–0.73 0.6 2 0.8
0.9 2 0.8
5–7.49 30 0.27–0.35 6–8 0.5–0.6 0.73 0.6 2 0.8
0.9 2 0.8–0.95
7.5–9.99 3 0.30 7 0.6 0.73 0.6 2 0.8
10–14.99 16 0.31–0.36 7–8 0.6 0.73–0.74 0.6 2 0.8
0.9 2 0.8–95
0.98 0 0.95
15–19.99 116 0.3–0.37 7–8 0.6 0.73–0.74 0.9 2 0.8
0.98 0 0.95
>20 44 0.3–0.35 6–7 0.6–0.8 0.73–0.75 0.9 2 0.95
0.98 0 0.95
  1. Model input symbols: [3, 16] R 0 average annual basic reproduction number for WPV of serotype 1, tr take rate of serotype 2 tOPV, POL3 RI coverage with 3 or more non-birth doses, TC true coverage of each SIA, p oro proportion of transmissions via oropharyngeal route
  2. aDefined as the average Rn of OPV2 over the one-year period preceding the switch
  3. bThe global model uses R0 for WPV1 to characterize variability in subpopulations, R0 for serotype 2 WPV equals 0.9 times the values shown in this column
  4. cPopulation shows long time until Rn of OPV2 exceeds one because of an indigenous cVDPV2 outbreak in one of its subpopulations following the switch and a subsequent mOPV2 response