The flu virus is constantly changing, with no two flu
exactly the same strains of virus. This is why each year, the World
Health Organization looks at which flu strains are most likely to be
in circulation when that year’s winter season arrives. In February,
it recommends three strains, and the vaccine manufacturers
develop flu vaccines based on this advice.1
Did you know?
Each year’s flu vaccine is the same for the
of the northern hemisphere, not just the UK.
It usually becomes available from late
September/early October, in readiness for the flu
season, when cases start to rise, generally