An epidemic viral infectious disease characterized by acute nasal catarrh, or by inflammation of the throat or the bronchi, and usually accompanied by fever and general weakness; also called grippe. It is caused by several forms of RNA virus which mutate readily and thereby render vaccines prepared against older forms ineffective, often requiring a new form of vaccine for each new outbreak.
an acute infectious viral disease characterized by fever, muscle aches, and respiratory tract and gastrointestinal tract symptoms.
Common, contagious respiratory infection caused by a virus. Incubation after exposure is 24 to 48 hours.