Yellow fever

Yellow fever, infectious disease caused by a virus carried by mosquitos of the genus Aëdes and occurring in tropical Americas and Africa. The disease consists of fever, headache, backache, prostration, and vomiting of sudden onset. Protein loss in the urine, kidney failure, and liver disorder with jaundice are also frequent. Hemorrhage from mucous membranes, especially in the gastrointestinal tract, is also common. A moderate number of cases are fatal, but a mild form of the disease is also recognized. Vaccination to induce immunity is important and effective as no specific therapy is available; mosquito control provides a similarly important preventive measure.