Sense checks for Gavi human rabies vaccine projections

Import projected country population and associated data - project_bites.R

Data (all in data folder) compiled for Gavi VIS (prepped_data_final.csv):
- world bank human population projections (2018 onwards)
- Human Dog Ratios (exposure risk)
- Urban/ rural populations (relates to dog ownership & PEP access)
- Human development index, HDI (relates to PEP access)
- Dog vaccination coverage (exposure risk) Revised HDR to consider religion (% muslim data sourced)
Use functions to project bites (rabid & healthy & PEP) - R/HelperFun.R

Incorporate vial sharing calculations: free; decentralized & vial size
Project over time horizon for 2 scenarios:
- SQ vs free PEP with improved access (decentralization) using IPC regimen
- outputs in outputs folder
- review comparison figures across countries & HDI

Key assumptions & concerns

% increase PEP seeking with Gavi support & saturation

free PEP increases demand (saturating curve - but may increase further in Asian settings
decentralization increases access (exponential curve - starts lower in SSA based on HDI)

Vial size = 1 ml - but little change with 0.5mL vials, though increased resilience in settings prone to surges Full compliance

Human dog ratio is more variable than country estimates
Expect +/- 20% per annum based on bite variability in data
Assumptions on health seeking changes with improved access likely to differ considerably