Estimate | Distribution | Reference/source | |

Additional cost parameters and assumptions | |||

Parameters to estimate cost of wheelchair to both household and provider | |||

% of children needing a wheelchair: severe CZS | 81.9% | Point estimate | Expert opinion |

% of children needing a wheelchair: moderate CZS | 5.0% | Point estimate | Expert opinion |

% of children needing a wheelchair: no CZS | 0.1% | Point estimate | Expert opinion |

Wheelchair cost to the health provider (R$962.5) US$, 2017 | 301.4 | Point estimate | 27 |

Wheelchair cost (incl. adaptation) to the household (R$4000) US$, 2017 | 1252.7 | Point estimate | Expert opinion |

Replacement wheelchair at age (years) | 3,4,5,6,7 and 10 | Point estimate | Expert opinion |

Other costs to the government (education and disability benefit) | |||

Special creche from age 3 years for CZS (federal payment per pupil R$4420.7) US$, 2017 | 1384.5 | Gamma* | 45 |

Primary education from age 4 (federal payment per pupil: R$4080.7) US$, 2017 | 1278.0 | Gamma* | 37 |

Ratio cost special needs education/cost primary education | 1.2 | Lognormal | Expert opinion |

Disability benefit per year (monthly min. wage: R$937) US$, 2017 | 3521.5 | Point estimate | 46 |

Parameters to model costs and outcomes | |||

General | |||

Discount rate costs | 5% | Point estimate | 35 |

Discount rate outcomes | 5% | Point estimate | 35 |

Model length (years) | 5 and 10 | Assumption | |

Exchange rate Brazilian Real to US$, 2017 | 0.31 | Point estimate | 31 |

Average annual inflation rate Brazil 2008–2017 (mean, SE) | 6.1%, 1.9% | Beta | 36 |

Modelling clinical burden | |||

Mortality severe CZS year 1 (%, alpha, beta) | 4.9%, 6, 116 | Beta | Estimated from Rio de Janeiro Cohort |

Mortality severe CZS year 2 (%, alpha, beta) | 2.6%, 3, 113 | Beta | Estimated from Rio de Janeiro Cohort |

Mortality severe CZS year 3 (%, alpha, beta) | 0.9%, 1, 112 | Beta | Estimated from Rio de Janeiro Cohort |

Mortality severe CZS year 4 (%, alpha, beta) | 0.9%, 1, 111 | Beta | Assumed to be the same as year 3 |

Mortality severe CZS year 5 (%, alpha, beta) | 0.9%, 1, 110 | Beta | Assumed to be the same as year 3 |

Mortality severe CZS year 6–10 per year (%) | 0.3% | Beta | Assumed to be 1/3 of mortality in years 3–5 |

Mortality Brazil (moderate CZS and controls) year 1 (%, alpha, beta) | 1.30%, 13.0, 987.0 | Beta | 47 |

Mortality Brazil (moderate CZS and controls) year 2 (%, alpha, beta) | 0.10%, 1.0, 999.0 | Beta | Estimate based on infant and <5-year mortality47 |

Mortality Brazil (moderate CZS and controls) year 3 (%, alpha, beta) | 0.03%, 0.3, 999.7 | Beta | Estimate based on infant and <5-year mortality47 |

Mortality Brazil (moderate CZS and controls) year 4 (%, alpha, beta) | 0.03%, 0.3, 999.7 | Beta | Estimate based on infant and <5-year mortality47 |

Mortality Brazil (moderate CZS and controls) year 5 (%, alpha, beta) | 0.03%, 0.3, 999.7 | Beta | Estimate based on infant and <5-year mortality47 |

Mortality Brazil (moderate CZS and controls) year 6–10 per year (%, alpha, beta) | 0.01% | Beta | Assumed to be 1/3 of mortality in years 3–5 |

Cases of CZS Brazil confirmed | 3474 | Point Estimate | 5 |

Cases of CZS Brazil under investigation | 2659 | point estimate | 5 |

Cases of CZS Brazil probable | 743 | Point estimate | 5 |

Cases of CZS Brazil deceased (fetal death, stillbirth, infant death and child death) | 505 | Point estimate | 5 |

Disability weight severe cerebral palsy for severe CZS | 0.82 | Lognormal * | 33 |

Disability weight mild/moderate cerebral palsy for mild/moderate CZS | 0.36 | Lognormal * | 33 |

Length disability=time horizon of model (years) | 5 and 10 | Point estimate | Decided by study team |

Table 2 shows parameters used in the economic burden model, that were not estimated in the costing analysis. This includes parameters to model the cost of a wheelchair as well as other costs to the government, general model parameters such as discount rate and also parameters to model the epidemiological burden of CZS.

*Standard error assumed to be 10% of mean.

CZS, congenital Zika Syndrome.