Composite of
disease threat (severity × R₀ × CFR, peak disease + 20% of rest, single-mention diseases filtered out),
geographic spread (unique affected countries),
velocity (last 6h vs 24h baseline), and
volume (signals per day). Calibrated against
worldometers.info COVID-19 daily-case data — the Jan 2022 Omicron peak (~3.7M cases/day, 195 countries, accelerating, PHEIC) =
100. A currently-PHEIC disease (polio, mpox) with sustained signal pins score to ≥75. Bands:
0–24 LOW ·
25–49 MODERATE ·
50–74 ELEVATED ·
75–100 HIGH. Surveillance/media proxy — not a clinical model.