Table 1

Parameters

DescriptionSymbol*Base-case
(sensitivity values/distribution)		Source
Disease model
 No of serotypes Z 15
 Under-five colonisation prevalence fitted to40%Authors’ assumption based on41–48 50 65
 Contact rate β Fitted to under-five colonisation prevalence
 Immigration force of infection W 1e−06As in37
 Intrinsic duration of carriage for serotype z γ(z) 25–220 days (linearly increasing across serotypes)As in37 and based on66 67
 Reduction in susceptibility to Pneumococcus from carrying the fittest serotype μmax 0.25As in37
 Reduction in susceptibility to a serotype conferred by prior carriage of that serotype σ 0.5 (0.5, 0.8)≥0.5 based on results for Z=15 in37
 Shape parameter for the reduction in duration of carriage dependent on past colonisation ε 0.1 (0.1, 0.25 and 0.4)Based on37
 Case–carrier ratio (pneumococcal pneumonia, meningitis and other invasive pneumococcal disease)Fitted to disease incidence given colonisation prevalenceBased on5 52 65 68
 Case fatality rateFitted to death rateBased on5 51 52 65
Treatment
 Seek treatmentWealth quintile I: 48%; II: 51%; III: 60%; IV: 66%; V: 75%Based on34 35 69
 Probability seek care at public provider (if seek care)

  • Wealth quintile I: 55% (triangular min=44%, max=66%, mode=55%);

  • II: 51% (triangular 40%, 61%, 51%);

  • III: 43% (triangular 35%, 52%, 43%);

  • IV: 39% (triangular 31%, 47%, 39%);

  • V: 26% (triangular 21%, 32%, 26%)

 Receive appropriate treatment at health provider95%Authors’ assumption
 Inpatient meningitis costBased on54 69 70
  Public providersUS$191 (triangular min=US$134, max=US$248, mode=US$191)
  Private providersUS$275 (triangular min=US$193, max=US$358, mode=US$275)
 Inpatient pneumonia costBased on54 69 71
  Public providersUS$93 (triangular min=US$65, max=US$121, mode=US$93)
  Private providersUS$214 (triangular min=US$150, max=US$278, mode=US$214)
 Inpatient other pneumococcal disease costBased on54 69
  Public providersUS$76 (triangular min=US$53, max=US$99, mode=US$76)
  Private providersUS$194 (triangular min=US$136, max=US$252, mode=US$194)
 Outpatient costBased on54 69
  Public providersUS$7.55 (triangular min=US$5.30, max=US$9.80, mode=US$7.55)
  Private providersUS$9.47 (triangular min=US$6.60, max=US$9.80, mode=US$12.30)
 Unattended pneumonia costUS$1.05 (triangular min=US$0, max=US$1.40, mode=US$1.05) 72
 Antibiotics clear colonisation or symptomatic infection50%Authors’ assumption based on73–75
 Exogenous antibiotic prescription rate (per day)0.001327Based on IMS Health MIDAS database
Vaccine
 PCV13 % of casesMost common serotypes representing approximately 70%Based on38 56
 Per-person vaccine efficacyp0.6As in37, estimated using76
 Per-child cost in scenario 1†US$13.60 (triangular min=US$6.35, max=US$18.95, mode=US$13.60)Based on WHO cMYP tool
 Per-child cost in scenario 2†US$13.50 (triangular min=US$6.25, max=US$18.85, mode=US$13.50)Based on WHO cMYP tool

  • Values varied for sensitivity are in parentheses. Costs in 2014 US dollars.

  • *Symbols for Cobey and Lipsitch 2012 model.

  • †Three doses at US$3.30 per dose and training, syringe, wastage costs (5% vaccine wastage rate and 10% syringe wastage rate) and a 25% buffer stock. Ranges for the sensitivity assume US$1 to US$5 per dose.

  • cMYP, comprehensive multiyear plan; PCV, pneumococcal conjugate vaccine.