Tags: Disease.
Influenza commonly known as the flu is an infectious disease of birds and mammals caused by RNA viruses of the family Orthomyxoviridae the influenza viruses. The most common symptoms are chills fever runny nose sore throat muscle pains headache (often severe) coughing weakness/fatigue and general discomfort. Although it is often confused with other influenza-like illnesses especially the common cold influenza is a more severe disease caused by a different type of virus.
