Annex 2 splits public health events into two pathways: four Box A diseases that trigger immediate Article 6 WHO notification upon a single confirmed or suspected case, and all other Box B or unusual events, which require at least two affirmative answers across four standardized risk questions within 48 hours.
Statutory source: WHO IHR (2005) Annex 2 Official Text.
IHR (2005) Annex 2 Four-Dimensional Event Evaluator
Select the pathogen category first, then toggle the four statutory Annex 2 criteria to determine whether the National IHR Focal Point must notify WHO within 24 hours under Article 6.
Box A vs. Box B Triage Architecture
National IHR Focal Points frequently encounter edge cases where a Box B pathogen exhibits local endemicity. Box B listing does not exempt an event from assessment; rather, it flags pathogens that carry documented potential for rapid escalation and therefore require structured four-question scoring whenever cluster geometry or clinical severity departs from seasonal baselines.
| Annex 2 Tier | Pathogens & Scope | Criteria Needed | Assessment Clock | WHO Action |
|---|---|---|---|---|
| Box A (Always Notify) | Smallpox, wild-type poliomyelitis, human influenza (new subtype), SARS | 0 criteria needed (1 case suffices) | Immediate | Mandatory Article 6 notification within 24 hours |
| Box B (Priority List) | Cholera, pneumonic plague, yellow fever, viral haemorrhagic fevers (Ebola, Lassa, Marburg), West Nile fever, regional threats (e.g., MERS-CoV, Rift Valley fever) | ≥ 2 of 4 criteria answered Yes | ≤ 48 hours | Notify WHO within 24 hours of affirmative assessment |
| General Event Track | Unusual respiratory clusters, chemical/radiological incidents, unknown etiology syndromes | ≥ 2 of 4 criteria answered Yes | ≤ 48 hours | Notify WHO within 24h; if 1 Yes, re-assess or consult (Art. 8) |
Statutory Escalation Funnel
Archival Note: /annex2 Pathway Continuity
Requests directed to historical /annex2 decision documentation resolve permanently to this workbench so practitioners and researchers retain single-hop access to the four-question statutory threshold logic.