219.4 📌 章末速蚘

  • Dengue: ssRNA flavivirus, 4 serotypes, Aedes aegypti / albopictus vector
  • ADE: 2nd infection different serotype = severe risk (sub-neutralizing Ab + Fc entry)
  • Phases: febrile (1-3 d, high fever + bone pain) → critical (4-7 d, plasma leakage) → recovery (7-10 d, fluid reabsorption)
  • Warning Signs: abdominal pain, vomiting, plasma leakage, bleeding, lethargy, hepatomegaly, ↑ Hct + ↓ platelets
  • Severe Dengue: plasma leakage (DSS), bleeding, organ failure
  • Dx: NS1 antigen (early) + PCR (acute) + IgM (after day 3-5) + IgG (paired)
  • Tx: supportive + fluid management (no antiviral)
  • NO NSAIDs / aspirin (bleeding)
  • NO routine steroid (no benefit)
  • NO platelet transfusion unless active bleeding (even at very low counts)
  • Vaccines: Dengvaxia (seropositive only, controversial) + Qdenga (broader 2022, WHO prequalified 2024)
  • Vector control + DEET + bed nets = prevention
  • Taiwan endemic every 2-3 yr outbreaks; 2023 record ~ 40K cases
  • 2024 Americas record outbreak — climate change driving expansion
  • Differential: chikungunya (severe arthralgia), Zika (microcephaly + GBS), leptospirosis, malaria