Flu is a particularly nasty virus that flares up during the winter months. Each year, the virus mutates slightly, meaning that vulnerable groups need to be vaccinated each year to protect against new strains. Scientists around the world work hard to predict the particular strains that may abound each winter and create a vaccine purpose-built for the flu season.
This is a companion discussion topic for the original article at https://patient.info/news-and-features/does-the-flu-jab-make-you-immune-to-flu