Influenza is a contagious respiratory illness caused by influenza viruses that infect the nose, throat, and sometimes the lungs. It can cause mild to severe illness, and at times can lead to death. The best way to prevent flu is by getting a flu vaccine each year.
EMA and ECDC have reviewed currently available studies and epidemiological data to provide a common position for EU/EEA countries on the current need and potential benefit of a fourth dose (second booster dose) of mRNA COVID-19 vaccines.