Influenza vaccination: revision of the indication

Influenza is caused by the influenza virus. Because the virus is constantly changing, people do not build up life-long resistance, as frequently happens with other infectious diseases. This explains why there are annual epidemics. Healthy individuals are usually well able to withstand an infection, but for people in the risk groups, influenza can lead to serious illness and even death (for example as a result of pneumonia, diabetes dysregulation  or aggravation of lung and heart disease).