Table 3 Input parameters for cost-effectiveness analysis

Typhoid incidence and age distribution

Annual number of symptomatic typhoid fever cases per 100,000 people (without vaccination)

26.1 (14.0–45.7) before outbreak;

Up to 916 (823–1543) during outbreak;

224 (169–368) after outbreak

Based on output from transmission dynamic model fitted to culture-confirmed cases and population-based adjusted incidence

Average age of patients with typhoid infection (without vaccination) (years)

15.9 (13.8–19.3)

Based on output from transmission dynamic model fitted to culture-confirmed cases

Typhoid mortality

Probability of death if patients are admitted to hospital for typhoid infection

0.09 (0.02–0.28)

[38, 41] [42]

Proportion of deaths from typhoid infection occurring in patients not hospitalized

0.38 (0.02–0.73)

Assuming that on average about one of three deaths occur outside the hospital setting, from [23]

Average age at death from typhoid infection (years)

15.9 (13.8–19.3)

Assuming age distribution of deaths is the same as the age distribution of patients with typhoid

Antimicrobial resistance

Proportion of patients with typhoid infection with an AMR strain

0.001 (0.00–0.63) before outbreak;

Up to 0.96 (0.86–1.00) during outbreak;

0.65 (0.31–0.98) after outbreak

[25, 42]

Burden of AMR cases relative to antimicrobial-sensitive cases

2 (1–3)

[23]

Healthcare use

Probability of infected patients seeking healthcare

0.71 (0.64–0.77)

[26]

Probability that infected patients are admitted to hospital

0.04 (0.01–0.11)

[43] [42]

Length of stay in hospital (days)

6 (3–9)

[23]

Treatment costs

Cost of inpatient treatment

$214.38 ($164.41–$264.34)

[40]

Cost of outpatient treatment

$39.67 ($33.96–$45.39)

[40]

Cost of treatment for a patient not seeking professional medical care

$1.59 ($0.31–$2.86)

[40]

Vaccine-related costs

Vaccine procurement cost per dose (accounting for Gavi support)

Routine: $0.20

Campaign: $0.00

Assuming Gavi support and that Malawi remains in the initial self-financing phase

Injection and safety equipment

$0.23 ($0.21–$0.24)

[23]

Vaccine delivery cost per dose (accounting for Gavi support)

Routine^a: $1.61 ($0.36–$4.23)

Campaign: $0.40 ($0.23–$0.62)

Based on a meta-analysis of delivery costs for new vaccine introductions; see Bilcke et al. for details [23]

Number of years during which start-up costs of vaccine delivery program are incurred

2 (1–3)

[23]

Percent of routine vaccine delivery costs that are ongoing

64% (48–78%)

[23]

Disability-adjusted life-years

Disability-weights (from 0 = perfect health to 1 = death)

Severe illness, 0.21 (0.14–0.29); moderate illness, 0.052 (0.031–0.079); mild illness, 0.005 (0.002–0.011)

[44]; see Additional file 1: S1.2.3 for explanation of how disability weights were assigned to different healthcare use groups

Duration of illness in inpatients and outpatients (days)

16 (12–20)

[23]

Relative duration of illness for patients not seeking medical care (vs inpatients and outpatients)

0.5 (0.02–0.98)

[23]

Life expectancy (years)

62.7

[39]