West Nile virus

West Nile virus

noun

Definition of WEST NILE VIRUS

: a single-stranded RNA virus of the genus Flavivirus (species West Nile virus) that causes an illness marked by fever, headache, muscle ache, skin rash, and sometimes encephalitis or meningitis, that is spread chiefly by mosquitoes, and that is closely related to the viruses causing Japanese B encephalitis and Saint Louis encephalitis; also : west nile fever