The routine immunisation component is calculated using a standardised formula:

• Population × Scheduled Doses × Coverage × Wastage

The SIA component captures nOPV2 and bOPV requirements for outbreak response, endemic SIAs (in Afghanistan and Pakistan) and pre-cessation campaigns (in 2028-2029), using blended methodologies derived from experts with operational experience, immunity mapping, risk-based planning and historical shipment data.

The model converts these inputs into a consistent, comparable, and scenario-based projection for all vaccine types.

Key Data Inputs

The forecast relies on harmonised global datasets:

• Population: UN World Population Prospects 2026-2030
• Vaccine schedules: Based on 2025 national schedules, projected forward
• Coverage: WHO/UNICEF Estimates of National Immunisation Coverage (WUENIC)
• Wastage: Income-based assumptions (low income = 15% wastage, middle income = 10%, high income = 5%)
• SIA inputs: Inputs from experts with operational experience, immunity mapping, risk-based planning and historical shipment data

These inputs ensure consistency across countries while providing a structured basis for scenario testing

Methodology and Scenarios

The model produces multi-year demand disaggregated by vaccine and demand type (routine immunisation, outbreak response, endemic SIAs, pre-cessation SIAs).

Three scenarios are available, each varying the coverage assumption while holding other inputs constant:

• Scenario 1: 100 percent coverage
• Scenario 2: Highest IPV1 coverage achieved in the last five years
• Scenario 3: IPV1 coverage for 2024

Together, these present a 10-15% demand range, offering upper, middle and lower bounds for planning.

The model is sensitive to all inputs and is not intended to replace partner-specific models but rather to provide a shared reference point for alignment.

How to Use the Dashboard

The Power BI dashboard allows users to explore forecasted demand for 2026-2030, filtered by:

• Scenario
• Geography (country, region, global)
• Year
• Vaccine type

Two primary views are available:

• Maps: Clickable country-level visualisation of demand
• Charts: Detailed tables disaggregating routine immunisation and SIA demand

Limitations and Considerations

Forecasted quantities depend on multiple dynamic inputs – population accuracy, schedule shifts, changes in coverage, policy decisions, and evolving SIA needs.

Assumptions may need updating as the epidemiology evolves and policies shift.

The model therefore represents a living tool, to be updated and refined as new data and policies emerge.

Contact and Feedback

Please provide any feedback or questions to David Woods (woodsd@who.int).