When we are born we have some immunity that is passed over from our mothers and we acquire further natural immunity through disease exposure. However, some disease can cause life threatening complications and a vaccination can provide that immunity without the risk of exposure and developing the disease.
These first vaccinations do not build lifelong immunity and need topping up.
It's important that vaccines are given on time for the best protection, but if you or your child missed a vaccine, contact your GP to catch up.
NHS vaccinations and when to have them - NHS (www.nhs.uk)