Seeking immunity
Dear HIW, This is a question I have been pondering for a while. How do vaccines work? What do they put in your body and how do they know where to put them? Zack
These are incredibly topical questions, with scientists around the world currently aiming to produce a new life-saving vaccine. It’s the job of white blood cells to respond to an infection when it enters the body, recognising danger and acting quickly to eliminate it before it does any further damage. Before they can carry out this vital role, your immune system needs to build familiarity with each infection. Vaccinations prepare the body for a more efficient response by exposing the immune system to a weaker version of an infection. If you are exposed to the same virus or infection again, the body will recognise it and the specific cells needed to kill it will be created. Vaccines contain weakened or dead germs combined with a substance which helps to kick-start the process, called an adjuvant. Vaccines are usually injected deep into your muscles, where the contents can be absorbed efficiently into the bloodstream. When vaccines are being tested, the most effective methods are discovered and spread to other scientists. Once the most effective entrance into the body is found, the bloodstream will carry the cells throughout the body, and you build up your defences.