Yellow Fever Virus (YFV) is a member of the family Flaviviridae.
The disease is caused by yellow fever virus and is spread by the bite of an infected female mosquito.
It infects only humans, other primates, and several types of mosquitoes. In cities, it is spread primarily by Aedes aegypti, a type of mosquito found throughout the tropics and subtropics. Nearly 90 percent of infections occur in African nations.
Yellow fever is a viral disease of typically short duration. In most cases, symptoms include fever, chills, loss of appetite, nausea, muscle pains particularly in the back, and headaches. Symptoms typically improve within five days. In about 15% of people, within a day of improving the fever comes back, abdominal pain occurs, and liver damage begins causing yellow skin.