Table 1 Dengue severity stratification according to 1997 and 2009 World Health Organization (WHO) guidelines

Acute febrile illness with ≥ 2 of the following symptoms:

 Headache

 Retro-orbital pain

 Myalgia

 Arthralgia

 Rash

Haemorrhage manifestations

 Leukopenia

Following must be all present:

 Fever or history of fever

 Haemorrhage tendencies (as manifested by a positive tourniquet test, petechiae/purpura/ecchymoses, mucosal bleeding)

 Thrombocytopenia

 Plasma leakage (a rise in the haematocrit, pleural effusion, ascites)

All four criteria of DHF plus evidence of circulatory failure evidenced by:

 Rapid and weak pulse

 Narrow pulse pressure (< 20 mm Hg)

 Hypotension

 Cold clammy skin and restlessness

Fever and two of the following symptoms:

 Nausea or vomiting

 Rash

 Bodyaches

 Positive tourniquet test

 Leukopenia

Similar features of DWoWS with the following warning signs:

 Abdominal pain

 Persistent vomiting

 Lethargy or restlessness

 Liver enlargement

 Increase in HCT and decrease in platelet count

Patients with any of the following features:

 Severe plasma leakage leading to Shock, fluid accumulation with respiratory distress

 Severe bleeding

 Severe organ impairment