Seasonal Flu Vaccination Flu (also known as influenza) is a
highly infectious illness caused by the flu virus. It spreads
rapidly through small droplets coughed or sneezed into the air
by an infected person. For most people, flu is unpleasant but
not serious. You will usually recover within a week. Studies
have shown that flu vaccines provide effective protection
against the flu, although protection may not be complete and may
vary between people. Protection from the vaccine gradually
decreases and flu strains change over time. Therefore, new
vaccines are made each year and people at risk of flu are
encouraged to be vaccinated every year. The flu vaccination is
offered to people in at-risk groups. These people are at greater
risk of developing serious complications if they catch flu, such
as pregnant women and elderly people.