Flu can cause serious complications such as pneumonia, especially in those aged 65 and older, pregnant women and children and adults with long-term medical conditions. An increase in flu cases leads to an increase in heart attacks and strokes.
It is easy to pass on the flu and anyone infected can spread the disease from 1 day before symptoms begin (asymptomatic) and for 3 to 5 days after developing symptoms
Flu occurs every winter, but it is not possible to know whether there will be a mild or a severe season in each year. The flu vaccine helps your immune system to produce antibodies to fight the virus. If you have been vaccinated and you come into contact with the virus, these antibodies will attack it and stop you from getting sick.
The flu vaccine starts to work within two weeks.