Methodology

Data sources & methodology

We don't generate primary epidemiological data. We aggregate, normalise and link back to official sources. Every data point on the map is traceable.

SourceRoleUpdate frequency
WHO Disease Outbreak NewsOfficial global outbreak bulletinsOn reportVisit
CDC NNDSSUS weekly notifiable disease reportsWeeklyVisit
ECDC Surveillance AtlasEuropean annual surveillance dataAnnualVisit
PAHO/WHO AmericasLatin American case counts and alertsWeekly–monthlyVisit
ProMEDCommunity-curated outbreak signalsContinuousVisit

Methodology

  • Active alerts are pulled from WHO DON and ProMED feeds and de-duplicated.
  • Historical cases are joined to country/region geographies (ISO 3166).
  • Endemic zones are derived from long-term published epidemiology, not from individual alerts.
  • We prefer incomplete transparency over false precision — when data is sparse we say so.

Limitations

  • Public surveillance lags real events by days, weeks or months.
  • Reporting coverage and case definitions vary between countries.
  • Country-level polygons don't reflect within-country variation.