Table 1. Criteria for severe dengue according to World Health Organization guidelines 1997 and 2009.

Criteria WHO 1997	Criteria WHO 2009
DHF
Dengue with all of the following 4 components:	Dengue with any of the following:
1. Fever	1. Severe plasma leakage leading to shock
2. Hemorrhagic tendency	or respiratory distress
3. Thrombocytopenia (<100×109 cells/L)	2. Severe bleeding as evaluated by clinicians
4. Plasma leakage:	3. Severe organ failure
a. Pleural effusion or ascites and/or	a. Liver (ASAT, ALAT >1000 U/L)
b. Minimum 20% hematocrit change and/or	b. Central nervous system: impaired consciousness
c. High hematocrit for population/age/sex and/or	c. Heart and other organs
d. Low serum protein
DSS
DHF and circulatory failure

Abbreviations: WHO: World Health Organization; DHF: dengue hemorrhagic fever; DSS: dengue shock syndrome; ALAT: alanine aminotransferase; ASAT: aspartate aminotransferase.