Dengue

Dengue fever is a viral infection that can progress to viral haemorrhagic fever (other examples include yellow fever, Lassa fever, Ebola).

Aetiology

• dengue virus is a RNA virus of the genus Flavivirus
• transmitted by the Aedes aegypti mosquito
• incubation period of 7 days

Clinical features

Patients with dengue fever can be classified as follows:

• dengue fever:
  • without warning signs
  • with warning signs
• severe dengue (dengue haemorrhagic fever)

Dengue fever

• fever
• headache (often retro-orbital)
• myalgia, bone pain and arthralgia ('break-bone fever')
• pleuritic pain
• facial flushing (dengue)
• maculopapular rash
• haemorrhagic manifestations e.g. positive tourniquet test, petechiae, purpura/ecchymosis, epistaxis
• 'warning signs' include:
  • abdominal pain
  • hepatomegaly
  • persistent vomiting
  • clinical fluid accumulation (ascites, pleural effusion)

Severe dengue (dengue haemorrhagic fever)