Pathophysiology of Dengue Fever

Introduction to Dengue Fever

The dengue virus (DENV) is transmitted by Aedes aegypti mosquitoes, with an incubation period of 4-8 days before symptom onset 1
Following infection, viral RNA is detectable in serum from approximately 2 days before to 1 week after illness onset, with peak viremia occurring during the acute febrile phase 2

The American College of Physicians recommends that fever, headache, retro-orbital pain, myalgia, and arthralgia result from the cytokine storm triggered by viral infection and immune activation 1
The characteristic dengue rash typically appears during days 3-7 of illness, coinciding with the defervescence period when fever subsides 3

The World Health Organization notes that thrombocytopenia combined with rising hematocrit represents a critical warning sign of progression to severe dengue 1, 4
DSS occurs when plasma leakage becomes severe enough to cause hypovolemia, leading to hypotension (systolic BP <90 mmHg) or narrow pulse pressure (<20 mmHg) 4
Approximately 15% of pregnant women develop dengue shock syndrome compared to 5% of non-pregnant individuals, likely due to pregnancy-related immune and hemodynamic changes 5

Early recognition of warning signs and appropriate supportive management can reduce case-fatality rates to <0.5% in hospitalized patients 1, 2
The Centers for Disease Control and Prevention recommends that understanding that dengue shock behaves differently from bacterial septic shock is crucial—the underlying plasma leakage pathophysiology requires careful fluid management to avoid over-resuscitation 4