Influenza, commonly known as the 'flu, is an infectious disease that infects birds and mammals (primarily of the upper airways and lungs in mammals) and is caused by an RNA virus of the Orthomyxoviridae family (the influenza viruses). The most common and characteristic symptoms of influenza in humans are fever, pharyngitis (sore throat), myalgia (muscle pains), severe headache, coughing, and malaise (weakness and fatigue).[1] A cold and a 'stomach flu' are very different from a flu. Influe ...
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Influenza Organizations