Public Health Risk Intelligence

US Measles County Risk Forecast

A county-level rare-event forecasting tool designed to highlight where measles may emerge next, where it may spread faster, and which counties warrant the most attention overall.

Primary view
Overall County Risk
Best interpreted as a relative risk ranking, not a guaranteed case forecast.
Last Date of Data
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Last Refreshed
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Forecast Week Of
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Interactive map

County Risk Surface

The map is most useful for comparing counties to one another within the selected horizon.

Methodology

How to read this model

This is a county-level rare-event risk model. Because measles is highly intermittent at the county-week level, the outputs are best interpreted as relative risk rankings rather than literal predictions of guaranteed future case counts.

Overall County Risk formula

Risk Score = 0.35 × Emergence Risk + 0.35 × Spread Pressure + 0.20 × Importation Context + 0.10 × Susceptibility / Seasonality Context

Model Inputs and Variables

Case History

The model uses recent measles case history including cases in the past week, past month, cumulative cases, and lagged case trends to identify active outbreak clusters and recent transmission.

Movement / Importation Pressure

County-to-county commuting flows and nearby county case activity are used to estimate importation pressure, representing the likelihood that measles cases may be introduced into a county from other areas.

Vaccination / Susceptibility

Vaccination coverage and exemption data are used to estimate a susceptibility proxy. Counties with lower vaccination coverage or higher exemption rates are considered more vulnerable if measles is introduced.

Geography / Spatial Spread

County geography, neighboring counties, and distance to recent outbreak areas are used to model spatial spread and regional clustering of cases.

County Population

County population from the Census API is used when available to improve incidence and spread normalization across counties of different sizes.

Seasonality / Transmission Context

Week-of-year seasonal terms and a transmission-style multiplier are included to give the model a better sense of temporal structure and spread conditions.

Data Sources

  • Johns Hopkins University CSSE – Measles case updates (county-level)
  • CDC – MMR vaccination coverage and exemptions among kindergartners
  • U.S. Census Bureau – County population estimates
  • U.S. Census Bureau – County-to-county commuting flows
  • U.S. Census Bureau – County geographic and FIPS reference files
  • OpenStreetMap – Basemap tiles

Model Limitations

  • This model produces relative risk rankings, not exact case forecasts.
  • Rare disease dynamics mean raw probabilities are very small and uncertain.
  • Vaccination data is based on school reporting and may lag real conditions.
  • Commuting flows are used as a proxy for movement and importation risk.
  • The model does not yet include airline passenger flows or a full transmission model.
  • Outputs should be interpreted as early warning indicators, not deterministic predictions.
Disclaimer: This site is an exploratory prototype for county-level measles risk ranking and outbreak analysis. The model outputs represent relative risk rankings and not guaranteed future case counts. This tool is intended for exploratory analysis, prioritization, and discussion, and should not be used as the sole basis for public health decisions.
Rankings

Highest Overall County Risk

County State Overall Risk Emergence Risk % Spread Pressure
Rankings

Highest Emergence Risk

County State Overall Risk Emergence Risk % Spread Pressure
Rankings

Highest Spread Pressure

County State Overall Risk Emergence Risk % Spread Pressure