Dengue hemorrhagic fever

Dengue hemorrhagic fever
Name	Dengue hemorrhagic fever
Synonyms	Severe dengue
Specialty	Infectious disease, WHO
Symptoms	Fever, bleeding, plasma leakage, shock
Complications	Hypovolemic shock, organ failure
Onset	2–7 days after mosquito bite
Causes	Dengue virus (four serotypes)
Risks	Prior dengue infection, Aedes aegypti exposure
Diagnosis	Clinical criteria, laboratory tests
Prevention	Vector control, vaccination

Dengue hemorrhagic fever is a severe, potentially fatal manifestation of dengue virus infection characterized by plasma leakage, thrombocytopenia, and hemorrhagic tendencies. It most commonly follows secondary infection with a different dengue serotype and is a major concern in tropical and subtropical regions, prompting responses by international organizations and national ministries of health. Clinical recognition and public-health measures link to global initiatives and programs addressing vector-borne diseases.

Introduction

Dengue hemorrhagic fever is caused by four antigenically related serotypes of the dengue virus within the Flavivirus genus and transmitted primarily by the mosquito species Aedes aegypti and Aedes albopictus. The condition gained international attention after outbreaks in Southeast Asia, the Americas, and the Western Pacific, engaging agencies such as the WHO, CDC, PAHO, and national public health institutes including the Thai Ministry of Public Health and Instituto Nacional de Salud. Historical epidemics prompted research collaborations with institutions like the Rockefeller Foundation, Institut Pasteur, and universities such as Harvard University and Mahidol University.

Signs and symptoms

The clinical course can progress from high fever and myalgia to warning signs including persistent vomiting, abdominal pain, and mucosal bleeding, with laboratory correlates such as rising hematocrit and falling platelet counts. Patients may present with petechiae, ecchymoses, epistaxis, and gastrointestinal hemorrhage requiring intervention by surgical teams or transfusion services tied to hospitals like Charité – Universitätsmedizin Berlin or Hospital das Clínicas da Universidade de São Paulo. Severe cases may develop dengue shock syndrome necessitating intensive care at centers such as Johns Hopkins Hospital or Singapore General Hospital, and may involve organ dysfunction observed in referrals to facilities like Royal Prince Alfred Hospital or Queen Mary Hospital.

Pathophysiology

Pathogenesis involves complex immunological interactions including antibody-dependent enhancement (ADE), memory T-cell responses, and cytokine storms; these mechanisms have been explored in laboratories at NIH, Wellcome Trust Sanger Institute, and Cold Spring Harbor Laboratory. Secondary infection with heterologous serotypes predisposes to severe plasma leakage mediated by endothelial dysfunction, complement activation, and vasoactive mediators investigated in cohorts by Oxford University and University of São Paulo. Genetic and host factors studied in populations by National University of Singapore and University of Malaya influence susceptibility and severity, paralleling research collaborations with London School of Hygiene & Tropical Medicine and Karolinska Institutet.

Diagnosis

Diagnosis relies on clinical case definitions promulgated by the WHO and laboratory confirmation via detection of viral RNA by RT-PCR, antigen NS1 assays, or serology (IgM/IgG) performed in reference laboratories such as CDC and Institut Pasteur. Imaging modalities including ultrasound or radiography at sites like Mayo Clinic and Cleveland Clinic detect pleural effusions and ascites indicative of plasma leakage. Differential diagnosis includes hemorrhagic fevers investigated by USAMRIID and tropical diseases seen at Hospital for Tropical Diseases, Ho Chi Minh City.

Treatment and management

Management is largely supportive and guided by WHO protocols, emphasizing fluid resuscitation, hemodynamic monitoring, and judicious use of blood products coordinated with transfusion services at institutions such as American Red Cross and national blood banks. Severe cases may require intensive care interventions applied in tertiary centers like Mount Sinai Hospital and Royal Brisbane and Women's Hospital, with adjunctive therapies evaluated in clinical trials by organizations including Institute for Clinical Evaluative Sciences and Bill & Melinda Gates Foundation-funded consortia. Corticosteroids and antiviral agents remain investigational in trials led by NIAID and pharmaceutical partners such as Sanofi and Takeda Pharmaceutical Company.

Prevention and control

Vector control strategies—source reduction, insecticide application, and community mobilization—are central and have been implemented in programs run by municipal authorities in cities like Singapore, Bangkok, and Rio de Janeiro. Vaccination efforts include licensed vaccines and candidates developed by manufacturers such as Sanofi Pasteur and Takeda, with policy evaluations by bodies like the SAGE and national immunization programs in countries including Philippines and Mexico. International initiatives by WHO and partnerships with NGOs such as Doctors Without Borders support integrated vector management and outbreak response.

Epidemiology and public health impact

Dengue hemorrhagic fever incidence has increased with urbanization and international travel affecting regions across Southeast Asia, the Caribbean, and the Americas, prompting surveillance by agencies like PAHO and national centers such as Instituto Evandro Chagas. Large outbreaks have occurred in locations including Philippines, Brazil, Thailand, and India, influencing health policy debates in parliaments and ministries such as the Government of Brazil and Government of India. The economic and health burden has led to modeling and burden studies by universities like Imperial College London and research institutes such as Institute for Health Metrics and Evaluation, informing WHO guidelines and global health strategies.

Category:Dengue