What are the symptoms of the flu?

Symptoms of influenza, commonly called the flu, include coughing, headache and chest discomfort, according to WebMD. A person suffering from influenza may also have a high fever that lasts for a few days, in addition to muscle aches, weakness and fatigue.

Influenza is a virus that attacks the respiratory system. It is highly contagious, spread through respiratory secretions. According to WebMD, symptoms of influenza appear from one to four days following infection.

Because influenza is a virus, it is not treatable with antibiotics, which are used to treat bacterial infections, explains WebMD. Rather, there are antiviral medications that are used to treat influenza.