Influenza virus is the cause of influenza. This is an acute respiratory disease that spreads rapidly and can easily develop into an epidemic if not well controlled. Understanding how influenza virus changes helps improve the effectiveness of disease prevention.

Research into the genetic changes and genetic makeup of seasonal influenza viruses is important for public health. It can help determine whether vaccines and antiviral drugs are still effective against circulating influenza viruses, as well as understand the risk of influenza viruses in animals infecting humans.