The document discusses influenza and the common cold. It describes the symptoms of the common cold and treatments that focus on relieving symptoms rather than treating the underlying viral infection. It then defines influenza as a highly contagious infection of the respiratory tract caused by influenza viruses. It notes that influenza viruses can undergo antigenic drift or shift and discusses how influenza spreads, its signs and symptoms, who is at highest risk, and that treatment focuses on rest and antiviral drugs like Tamiflu since there is no cure.