How effective is the vaccine? - If I have a flu jab, can I still get flu?

Flu vaccinations are 70-80% effective, provided that there is a good match between the strains used to make the vaccine, and the strains of flu that are going around. There are very sophisticated systems in place for monitoring strains of flu around the world, so it is increasingly possible to predict which strains are most likely to cause trouble. Protection is excellent against the strains from which the vaccine is made, and even if you catch the flu, the illness will almost certainly be milder than if you had not been vaccinated.