Number of Dengue Virus Serotypes
Four distinct serotypes of dengue virus are recognized: DENV-1, DENV-2, DENV-3, and DENV-4. 1
Serotype Classification
The dengue virus exists as four antigenically distinct serotypes that are genetically distant from one another 2, 3. These serotypes are:
- DENV-1 (Dengue virus type 1) 2, 3, 4
- DENV-2 (Dengue virus type 2) 2, 3, 4
- DENV-3 (Dengue virus type 3) 2, 3, 4
- DENV-4 (Dengue virus type 4) 2, 3
Clinical Significance of Multiple Serotypes
Each serotype can cause the full spectrum of dengue disease, ranging from mild febrile illness to severe dengue hemorrhagic fever or dengue shock syndrome 2, 3. The existence of four distinct serotypes has important clinical implications:
Primary infection with any serotype provides long-lasting immunity to that specific serotype but only temporary cross-protection against the other three serotypes 2
Secondary infection with a different serotype (heterotypic infection) significantly increases the risk of severe disease through antibody-dependent enhancement (ADE) 2
Co-circulation of multiple serotypes in the same geographic region has been associated with increased severity of clinical cases 4, 5
Genetic Diversity Within Serotypes
Beyond the four serotypes, each serotype contains multiple genotypes with different genetic lineages 2, 3, 5. For example, DENV-2 has been subdivided into different genotypes including the American/Asian genotype that circulates in Central America 5. However, these genotypes remain within their respective serotypes and do not constitute additional primary serotypes 5.