What is the causative virus of dengue (Dengue fever)?

From the Guidelines

Dengue is caused by the dengue virus (DENV), which belongs to the Flaviviridae family. This virus is an RNA virus with four distinct serotypes (DENV-1, DENV-2, DENV-3, and DENV-4) 1. The virus is primarily transmitted to humans through the bites of infected female Aedes mosquitoes, mainly Aedes aegypti and to a lesser extent Aedes albopictus.

Key Characteristics of Dengue Virus

• The virus replicates in the mosquito's midgut before spreading to its salivary glands 1
• The virus then gets injected into a new human host during subsequent blood meals
• Infection with one serotype provides lifelong immunity against that specific serotype but only temporary protection against the others 1
• Subsequent infections with different serotypes actually increase the risk of developing severe dengue, a potentially fatal complication characterized by plasma leakage, fluid accumulation, respiratory distress, severe bleeding, or organ impairment 1

Transmission and Diagnosis

• The virus is transmitted through the bites of infected female Aedes mosquitoes 1
• Diagnosis can be made using nucleic acid amplification tests (NAATs) or immunoglobulin M (IgM) antibody testing 1
• Dengue virus diagnosis should be made as soon as possible to initiate appropriate management and prevent complications 1

Management and Prevention

• Patients with clinically suspected dengue should receive appropriate management to monitor and treat shock and hemorrhage 1
• Women with laboratory evidence of possible Zika virus infection during pregnancy and their infants should be evaluated and managed for possible adverse outcomes 1
• Health care providers should consider the epidemiology of viruses known to be circulating at the location of exposure and clinical findings when making clinical and testing decisions 1

From the Research

Virus Responsible for Dengue

• The virus responsible for dengue is the dengue virus (DENV), which is a flavivirus 2, 3.
• DENV is a positive-stranded enveloped RNA virus that is principally transmitted by Aedes mosquitoes 2.
• There are four antigenically distinct serotypes of DENV, namely DENV-1 to DENV-4, with different genotypes and three structural proteins and seven non-structural proteins 2.

Characteristics of Dengue Virus

• Dengue virus is the cause of one of the most dangerous and common viral diseases in humans that are carried by mosquitoes and can lead to fatalities 3.
• The virus has been documented in tropical and subtropical climates in over 100 nations, with approximately 400 million cases and 22,000 deaths occurring due to dengue worldwide each year 2, 3.
• Clinical symptoms of dengue range from mild fever to severe dengue hemorrhagic fever (DHF) or dengue shock syndrome (DSS), with thrombocytopenia, leucopenia, and increased vascular permeability 2.

Serotypes of Dengue Virus

• There are four serotypes of dengue virus (DENV 1-4), which can cause a range of illness, with defining precisely which clinical characteristics are associated with the distinct serotypes being elusive 4.
• A study found that more shock and internal hemorrhage were observed in the period when DENV-2 predominated, whereas increased vascular permeability was associated to a greater degree with the DENV-1 period 4.
• The study also found that the DENV-1 season was associated with more hospitalized primary dengue cases and more primary DENV infections with severe manifestations 4.