## Viral Classification of Dengue **Key Point:** Dengue virus is classified in the genus **Flavivirus** within the family **Flaviviridae**. ### Dengue Virus Characteristics - **Genome:** Single-stranded, positive-sense RNA (~11 kb) - **Structure:** Enveloped icosahedral virion, ~50 nm diameter - **Serotypes:** Four distinct serotypes (DENV-1, DENV-2, DENV-3, DENV-4) - **Replication:** Cytoplasmic replication; forms replication complexes in endoplasmic reticulum ### Flavivirus Genus Members | Virus | Disease | Vector | |-------|---------|--------| | **Dengue virus** | Dengue fever, DHF, DSS | Aedes aegypti, Aedes albopictus | | **Yellow fever virus** | Yellow fever | Aedes aegypti | | **Zika virus** | Zika fever, congenital abnormalities | Aedes aegypti, Aedes albopictus | | **West Nile virus** | West Nile fever | Culex mosquitoes | | **Japanese encephalitis virus** | Japanese encephalitis | Culex mosquitoes | **High-Yield:** Chikungunya virus, despite similar epidemiology and transmission, belongs to genus **Alphavirus** in family **Togaviridae** — a different family from dengue. This is a common exam trap. **Mnemonic:** **FLAVI** = **FL**avivirus = **F**ruit, **L**iver, **I**nfection (Yellow fever affects liver; dengue affects multiple organs). Flaviviruses are "flavour" viruses — diverse, widespread, significant. **Clinical Pearl:** All four dengue serotypes can cause severe dengue (dengue haemorrhagic fever and dengue shock syndrome), particularly with secondary infection by a different serotype due to antibody-dependent enhancement (ADE).
Sign up free to access AI-powered MCQ practice with detailed explanations and adaptive learning.