evidence: The flu vaccine is your best defense against the flu. The flu vaccine is recommended every year in the fall or winter, ideally before the flu season starts. Almost everyone who is at least 6 months of age should get a flu vaccine. [...] The flu vaccine also helps protect people close to you because you're less likely to spread the flu to them if you're vaccinated. [...] The flu and other respiratory illnesses are caused by different viruses. The flu vaccine won't protect you against any other illnesses, such as COVID-19 or respiratory syncytial virus (RSV). Keeping up to date with all recommended vaccinations will help protect you through the respiratory illness season.