Dengue Fever: Treatment

WHO Severity Classification (2009)

Phase-Based Management

1. Febrile phase - days 1-7: fever, myalgia, headache, rash
2. Critical phase - days 3-7 (around defervescence): plasma leakage, risk of shock
3. Convalescent phase: fluid reabsorption, improvement

1. Uncomplicated Dengue (Without Warning Signs)

• Hydration: Encourage generous oral fluids (water, ORS, coconut water, fruit juice). Oral rehydration solutions are preferred.
• Antipyretics: Paracetamol (acetaminophen) every 6 hours, max 4 doses/day, to control fever and pain.
• Avoid: NSAIDs (ibuprofen, naproxen), aspirin, and salicylate-containing drugs - these worsen bleeding risk and can cause gastritis/platelet dysfunction.
• Rest.
• Monitoring: Check platelet count and hematocrit daily from day 3 until 1-2 days post-defervescence. Any warning signs warrant immediate hospital admission.

2. Dengue with Warning Signs

• IV crystalloid fluids (isotonic saline or lactated Ringer's) if oral intake is inadequate or vomiting persists.
• Monitor: vital signs, urine output (target ≥0.5 mL/kg/hr), hematocrit, platelet count.
• Watch for early signs of shock: narrowing pulse pressure, tachycardia, cold extremities, prolonged capillary refill.
• Rising hematocrit (hemoconcentration) signals active plasma leakage - increase IV fluid rate.
• Falling hematocrit without clinical improvement may indicate internal bleeding.

3. Severe Dengue (DHF / DSS)

Fluid Management (Key Principle)

• Start IV crystalloids (normal saline or lactated Ringer's) as early as possible, before shock develops.
• Algorithmic fluid management based on:
  • Clinical status (shock vs. no shock)
  • Hematocrit trends
  • Urine output
  • Signs of fluid overload
• With shock: more aggressive fluid resuscitation; if refractory to crystalloids, switch to IV colloids (e.g., dextran, gelatin).
• Blood products: transfuse packed red cells for significant bleeding or severe anemia; platelet transfusion generally reserved for active severe bleeding (platelet threshold alone is not an indication).

Hemorrhage Management

• Transfuse blood/blood products as needed for hemorrhagic complications.
• Steroids: Several studies have been done, but evidence remains inconclusive - not recommended routinely.

Convalescent Phase Caution

• As the plasma leak resolves (usually 48-72 hours after defervescence), fluid is reabsorbed from extravascular spaces.
• Reduce IV fluid rate during convalescence to avoid pulmonary edema and fluid overload.
• Hematocrit will fall due to dilution - do not misinterpret as continued bleeding.
• Signs of recovery: stable BP, spontaneous diuresis, appetite returns, rash may appear or desquamate.

Specific Contraindications

Special Populations

• Pregnant women: Dengue near term carries ~20% vertical transmission risk. Avoid NSAIDs, use paracetamol. Delivery during the critical phase is high-risk; manage with multidisciplinary team.
• Infants: Particularly at risk for severe disease; low threshold for IV fluids.
• Patients with comorbidities (diabetes, renal disease, cardiac disease): Fluid management requires extra caution due to reduced reserve.

Dengue Vaccine (Prevention)

• CYD-TDV (Dengvaxia): Live attenuated tetravalent vaccine, approved for ages 9-45 years in endemic areas. Important caveat: only seropositive individuals benefit; seronegative recipients actually face increased risk of severe dengue. Pre-vaccination serological testing is recommended.
• A newer vaccine, TAK-003 (Qdenga/Takeda), has been approved in multiple countries for ages 4+ and does not require prior seropositivity screening.

Disposition Summary

• Red Book 2021: Committee on Infectious Diseases, AAP, pp. 520-524
• Rosen's Emergency Medicine, pp. 2629-2630
• Harrison's Principles of Internal Medicine, 22E (2025), McGraw-Hill
• Yang et al., 2025 - systematic review on dengue management (PMID: 41037858) confirms that management remains supportive, centered on tailored fluid resuscitation and judicious blood product use for severe cases.
• CDC Dengue Case Management Pocket Guide (2024)