Table XII.

Model Inputs for the Northern India Model

Model input (symbol)	Best estimate	Source	Notes
Number of subpopulations (Bihar)	1
Number of subpopulations (WUP)	2		Subpopulation 1: undervaccinated subgroups (1/25th) of total WUP population; subpopulation 2: general population (24/25th) of total WUP population
Relative population size compared to all of India		125	According to the 2011 census, approximately 1.2 billion live in all of India, 104 million in Bihar, and 71 million in included districts for WUPa
- Bihar	0.086
- WUP	0.059
Number of age groups	9		0–2; 3–11 months; 1; 2; 3; 4; 5–9; 10–14; ≥ 15* years
Number of mixing age groups	3		0–4; 5–14; ≥ 15 years
Year when model run-up starts	1950
Year when R0 seasonality starts	1965
Year when die-out first allowed	1965
Average basic reproductive number (R0) (PV1)	13		Fitted within range for lowest tier (Table III); PV2&3 according to ratios in Table I
Proportional change in R0 due to seasonality ($\alpha$)	0.25		Seasonality modeled as step function
Day of seasonal peak in R0(pd)	195 (July 14)
Proportion of contacts reserved for individuals within the same mixing age group ($\kappa$)	0.35		For simplicity, assume equal values for each mixing age group
Proportion of transmissions via oropharyngeal route ($p^{oro}$)	0.3		Based on average of mean expert assessments for community and close contacts for type 1 in high R0 settings(19)
Proportion of potentially infectious contacts of individuals in subpopulation 1 in WUP that are with other individuals in subpopulation 1 in WUP (pwithin)	0.95		Force of infection as a result of mixing between subpopulations modeled using previously described approach;(13) (see Appendix A1) model does not include mixing between Bihar and WUP
Per-dose take rate (tr) (PV1;PV2;PV3)
- tOPV	0.35;0.50;0.30
- mOPV	0.50;NA;0.45
- bOPV	0.45;NA;040
Routine coverage with 3 or more doses by 1 year of age, birth dose coverage, and partial coverage	Time series 1980–2012	89
Characterization of routine tOPV vaccination, 1980–2012		89	Primary nonbirth doses at 6–10–14 weeks modeled as the cumulative effect of all 3 nonbirth doses upon entering the 3–11-months-old age group, taking into account partial coverage
- Doses at birth	1
- Cumulative effect of 3 primary nonbirth doses at ages (months)	3
Characterization of SIAs 1995–2012			See Appendix A4 for effective per-round impact assumptions by year and subpopulation in the absence of good data and resulting annual cumulative percentages of missed children
- Dates, durations, and target population of SIAs	Time seriesb
- Effective per-round impact ($\zeta$)	Varies
- Target age groups	0–4 years
Date of introduction of WPV3 into Bihar for 2007 outbreak	January 1, 2007

Acronyms: bOPV = bivalent OPV; mOPV = monovalent OPV; OPV = oral poliovirus vaccine; PV1,2,3 = poliovirus type 1, 2, and 3, respectively; SIA = supplemental immunization activity; tOPV = trivalent OPV; WUP = Western Uttar Pradesh

^*Age groups marked with an asterisk indicate age groups that count towards determining the fraction of newborns who receive maternal antibodies, based on the immune fraction in those age groups (see Appendix A1).

^aWe included the following districts: Agra, Aligarh, Baghpat, Bareilly, Bijnor, Budaun, Bulandshahr, Etah, Etawah, Farrukhabad, Firozabad, Gautam Buddha Nagar, Ghaziabad, Jyotiba Phule Nagar, Kanshiram Nagar, Mahamaya Nagar, Mainpuri, Mathura, Meerut, Moradabad, Muzaffarnagar, Pilibhit, Rampur, Saharanpur, Shahjahanpur.

^bInformation about SIA history based on Gacic-Dobo, 2009 (personal communication) and other information.^(126–128)