Dengue Hemorrhagic Fever

Dengue is an arbovirus flavivirus infection transmitted by Aedes. Infection ranges from asymptomatic to DF to DHF. DHF is severe: starts like DF, then abrupt deterioration on fever day 2-5 with multi-organ bleeding/shock, hemoconcentration, thrombocytopenia, leukocytosis, hepatomegaly. First described Thailand 1950; now Southeast Asia/Pacific/Caribbean. Two types: (1) DHF: typical early DF then sudden worsening (cold skin, rapid pulse, stupor/restlessness, sweating, hepatomegaly, petechiae/purpura, positive tourniquet test) on days 2-5. (2) Dengue shock syndrome: progressive BP/pulse-pressure fall leading to shock; patient initially conscious.

Common Symptoms

Coma; lymphadenopathy; shock; bleeding tendency; fever; hepatomegaly; hemoptysis; stupor; doctor

Causes and Pathogenesis

Flavivirus, +ssRNA; survives 5 years at -20°C, >8 years at -70°C in serum; killed 50°C/30 min, 100°C/2 min, acid/detergent/ether/UV/0.65% formalin. 4 serotypes, all pathogenic. Aedes aegypti/albopictus are vectors; patients/asymptomatic carriers are reservoirs (most infectious days 1-3 post-onset). Pathogenesis: Aedes bite → endothelial/mononuclear phagocyte replication → first viremia → lymphoid tissue replication → second viremia; immune complexes activate complement → increased vascular permeability; marrow suppression → leukopenia/thrombocytopenia. Pathology: capillary endothelial damage, plasma leak, perivascular hemorrhage/edema/lymphocyte infiltrate, reticuloendothelial hyperplasia.

Treatment

Drug therapy, supportive therapy

Preventive Measures

(1) Surveillance in endemic areas; early diagnosis/isolation (≥5 days in screened room); border quarantine. (2) Mosquito control: improve environment, eliminate Aedes breeding sites/stagnant water, spray adulticides. (3) Personal protection: balanced nutrition, exercise, insect repellent during epidemics.

Department to Visit

It is recommended to visit the Infectious Diseases department; an appointment can be booked on this platform before the visit.

Warm reminder: The above information is for health science reference only and cannot replace professional medical diagnosis. If you have related symptoms, please seek medical attention at a regular hospital promptly.