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Table 1 Model inputs that differ from those developed previously[20] after consideration of additional situation-specific data and revised SIA characterization

From: The potential impact of expanding target age groups for polio immunization campaigns

Model input (symbol) Value in Duintjer Tebbens et al. (2013) [[20]] New value
Generic model inputs:   
Ratio of R0 for PV3 vs. PV1 0.8 0.75
Average time to reach last reversion stag (ϵ, in days) (for PV1; PV2; PV3)a 547.5; 360; 547.5 620.5; 408; 620.5
Basis for demographic data World Population Prospects: The 2010 Revision [26] World Population Prospects: The 2012 Revision [27]
Tajikistan model inputs:   
Relative routine immunization coverage compared to most recent survey (used from 1992 forward) 0.9 0.88
Northern India model inputs:   
Number of subpopulations (Bihar) 1 2
Size of subpopulation relative to total population   
 - Bihar NA 10%
 - Western Uttar Pradesh 4% 10%
Proportional change in R0 due to seasonality (α) 0.25 0.20
Peak day of seasonal amplitude, WUP 195 (July 14) 165 (June 14)
Proportion of potentially infectious contacts of individuals in the under-vaccinated subpopulation with other individuals in the under-vaccinated subpopulation (p within )   
 - Bihar NA 0.70
 - Western Uttar Pradesh 0.95 0.70
Routine immunization coverage in the under-vaccinated subpopulation Increasing over time 0
Per-dose take rate (tr) (PV1; PV2; PV3)   
 - tOPV 0.35; 0.50; 0.30 0.35; 0.60; 0.27
 - mOPV 0.50; NA; 0.45 0.45; NA; 0.45
 - bOPV 0.45; NA; 0.40 0.42; NA; 0.42
Northwestern Nigeria model inputs:   
R0 8.0 7.5
Proportional change in R0 due to seasonality (α) 0.05 0.10
Day of seasonal peak in R0 (pd) 60 (March 1) 100 (April 10)
Basis for routine immunization coverageb POL coverage DTP coverage
Routine immunization coverage relative to reported data   
 - General population 1.08 1
 - Under-vaccinated subpopulation 0.29 0
Per-dose take rate (tr) (PV1; PV2; PV3)   
 - tOPV 0.45; 0.7; 0.4 0.45; 0.7; 0.35
 - mOPV 0.66; NA; 0.65 0.6; NA; 0.6
 - bOPV 0.54; NA; 0.52 0.54; NA; 0.54
  1. aThe original and new values equal 1.5 and 1.7 times the estimated time to reach viral protein 1 divergence thresholds defined by the Global Polio Laboratory Network, [28, 29], respectively.
  2. bContinued discussion of available routine immunization data in Nigeria determined that DTP coverage probably provides a more reliable estimate of routine immunization coverage for polio vaccine doses, because reported polio vaccine doses likely includes doses administered as part of SIAs.