Abstract
Each year, approximately 20,000 Americans die from influenza infections. Those particularly susceptible include the elderly and patients with chronic medical conditions. Immunoprophylaxis with an inactivated vaccine and chemoprophylaxis with an influenza antiviral drug help minimize influenza incidence. Here, we review the biology behind influenza viruses, clinical manifestations, diagnosis, treatment, and prevention measures, including the Advisory Committee on Immunization Practices' recommendations regarding the influenza vaccine.