Influenza is an acute disease of the respiratory system that occurs every year from autumn and the peak period for influenza in the northern hemisphere extending from November to March. It is caused by viruses and can affect people of all ages.
The incubation period is the time between exposure to the virus and the onset of symptoms of the disease. The incubation period for the flu is from two to four days.
Influenza or Common Cold?
The common cold is a mild infection often caused by a virus, different from those of the flu.
Separating the symptoms of the common cold from those of the flu can sometimes be difficult, but, in general, people with a common cold, runny or stuffy nose are more common symptoms.
While people with the flu: