flaviivirusten

Flaviiviruses are a genus of viruses within the family Flaviviridae. This genus is known for including a number of important human pathogens, many of which are transmitted by arthropods, particularly mosquitoes and ticks. The name "Flavivirus" originates from the Latin word "flavus," meaning yellow, and was derived from the name of the type species, yellow fever virus.

These viruses are enveloped and possess a positive-sense single-stranded RNA genome. Their genetic material is typically around 10-12 kilobases in length and is organized into three structural proteins (C, prM/M, and E) and seven non-structural proteins (NS1, NS2A, NS2B, NS3, NS4A, NS4B, and NS5). The E protein is particularly important as it mediates viral entry into host cells and is a major target for the host immune response.

Many flaviviruses are transmitted in a zoonotic cycle, meaning they circulate between animal populations and can spill over into human populations. Mosquito-borne flaviviruses include well-known examples such as dengue virus, Zika virus, West Nile virus, and Japanese encephalitis virus. Tick-borne flaviviruses include tick-borne encephalitis virus.

Infections with flaviviruses can range from asymptomatic or mild febrile illnesses to severe, life-threatening conditions. Symptoms can include fever, headache, rash, joint pain, and in more severe cases, encephalitis, meningitis, or hemorrhagic fever. Diagnosis is typically made through serological tests detecting antibodies or by detecting viral RNA or antigens. Prevention strategies often focus on vector control to reduce mosquito and tick populations and on vaccination where available, such as for yellow fever and Japanese encephalitis.