The incubation period – the time between when infection occurs and when symptoms appear – varies from virus to virus, but is usually limited between 2 and 15 days for<unk> es. The majority of infections, however, are asymptomatic. Among cases in which symptoms do appear, symptoms tend to be non-specific, resembling a flu-like illness, and are not indicative of a specific causative agent. These symptoms include fever, headache, malaise, rash and fatigue. Rarely, vomiting and hemorrhagic fever may occur. The central nervous system can also be affected by infection, as encephalitis and meningitis are sometimes observed. Prognosis is good for most people, but is poor in those who develop severe symptoms, with up to a 20% mortality rate in this population depending on the virus. The very young, elderly, pregnant women, and people with immune deficiencies are more likely to develop severe symptoms.<unk>  Disease(s) Incubation period Symptoms Duration of symptoms Complications Case fatality rate Vector(s) Primary host(s) Geographic distribution Does infection provide lifelong immunity? Dengue virus Dengue fever 3–14 days Asymptomatic in most cases; fever, headache, rash, muscle, and joint pains 7–10 days Shock, internal bleeding, and organ damage <1% with treatment, 1–5% without; about 25% in severe cases Aedes mosquitoes, especially Aedes aegypti Humans Near the equator globally Varies Japanese encephalitis virus Japanese encephalitis 5–15 days Asymptomatic in most cases; fever, headache, fatigue, nausea, and vomiting Encephalitis, seizures, paralysis, coma, and long-term brain damage 20–30% in encephalitis cases Culex mosquitoes, especially Culex tritaeniorhynchus Domestic pigs and wading birds Southeast and East Asia Yes Rift Valley fever virus Rift Valley fever 2–6 days Fever, headache, myalgia and liver abnormalities 4–7 days Hemorrhagic fever, meningoencephalitis 1% in humans; in pregnant livestock, 100% fatality rate for fetuses Culex tritaeniorhynchus and Aedes vexans Micropteropus pusillus and Hipposideros abae Eastern, Southern, and Western Africa Yes Tick-borne encephalitis virus Tick-borne encephalitis 7–14 days Fever, headache, muscle pain, nausea, vomiting, meningitis, and encephalitis Paralysis and long-term brain damage 1–2% Ixodes scapularis, Ixodes ricinus, and Ixodes persulcatus Small rodents Eastern Europe and Southern Russia Yes West Nile virus West Nile fever, encephalitis 2–15 days Asymptomatic in most cases; fever, headache, fatigue, nausea, vomiting, rash 3–6 days Swollen lymph nodes, meningitis, encephalitis, acute flaccid paralysis 3–15% in severe cases Culex mosquitoes Passerine birds North America, Europe, West and Central Asia, Oceania, and Africa Yes Yellow fever virus Yellow fever 3–6 days Fever, headache, back pain, loss of appetite, nausea, and vomiting 3–4 days Jaundice, liver damage, gastrointestinal bleeding, recurring fever 3% in general; 20% in cases with severe complications Aedes mosquitoes, especially Aedes aegypti Primates Tropical and subtropical regions of South America and Africa Yes
Arbovirus
Oncovirus
Coronavirus 
Coronavirus
Echovirus
Senecavirus
Orthohantavirus
Pandoravirus