Table 2. Severe Dengue (SD) according to the WHO 2009 dengue classification, and moderate dengue according to the definitions used for this analysis.

	Severe Dengue (SD)	Moderate dengue severity
Vascular leakage	- Shock (DSS) - Fluid accumulation with respiratory distress	- Serosal fluid accumulation*
Bleeding	- As evaluated by clinician, leading to haemodynamic instability**	- Mucosal bleeding (excluding uncomplicated haematuria***) without haemodynamic instability
Organ dysfunction	- Liver: AST or ALT ≥ 1000 U/L - CNS: Impaired consciousness (coma scale < 15 [GCS] or < 5 [BCS])	- Liver: 400 U/L ≤ ALT < 1000 U/L

* Serosal fluid accumulation was diagnosed either clinically or radiologically. Clinical fluid accumulation was defined as clinical pleural effusion or ascites on any day. Radiologically detected fluid accumulation (assessed within 24 hours of defervescence) was defined as pleural effusion by CXR or serosal fluid collection on ultrasound; see also Rosenberger et al., 2016 [33].

** Bleeding cases experienced gastrointestinal, skin or mucosal bleeding (e.g. nose bleed / bleeding at venepuncture sites; often multiple sites), which was evaluated as ‘severe’ by the treating physician based on the concern that the bleeding lead to haemodynamic instability. In most cases, severe bleeding was followed by administration of blood products.

*** Haematuria was defined either microscopically / dipstick test (≥10 erythrocytes/μl), or as macroscopic haematuria.