Flaviviridae is a taxonomic family comprised of viruses containing monopartite, linear, single-stranded RNA enveloped with icosahedral, spherical structure (about 40-60 nm in diameter).
The genus Flavivirus includes medically-important species such as the yellow fever virus, dengue virus, zika virus, and West Nile virus. The name Flaviviridae is derived from the Flavivirus species causing the yellow fever disease. The genus Hepacivirus includes the hepatitis C virus and Hepacivirus B. The genus Pegivirus includes the pegivirus A, B, and C. The genus Pestivirus includes the bovine virus diarrhea virus-1 and the hog cholera virus. All of these genera take a mammalian host. The mechanism of entry is clathrin-mediated endocytosis. They assemble and replicate in the host's cytoplasm.
Some of the species are transmitted by using an arthropod vector. For instance, the dengue virus is transmitted to a human host through an arthropod bite, particularly by an infected female Aedes mosquito. Viruses that use an arthropod for transmission are referred to as arboviruses (meaning arthropod-borne viruses).