Dengue is a viral infection transmitted by the Aedes mosquito. It causes a range of clinical presentations from a self-limiting febrile illness called dengue fever to a potentially lethal complication called severe dengue. Severe dengue is characterized by plasma leakage, fluid accumulation, respiratory distress, severe bleeding, or organ impairment. The course of dengue hemorrhagic fever involves an initial febrile phase followed by a critical phase with plasma leakage and potential progression to shock, and finally a recovery phase.