Vaccines teach our immune system how to create antibodies to protect us from diseases. This is a much safer way than our immune system learning this through catching the diseases. Once our immune system knows how to fight a disease, it can often protect us for many years. Since vaccines were introduced in the UK, diseases like polio, smallpox and tetanus that used to kill or disable millions of people are either gone or are now rarely seen. However, if we stop having vaccines, it’s possible for infectious diseases to quickly spread again. When getting vaccinated, we aren’t just protecting ourselves but also the people around us. Vaccines help prevent the spread of infection.
When we are given a vaccine, the immune system attacks it as if harmful microbes were attacking our body. White blood cells which are part of our immune system, create lots of antibodies to attach to specific markers on the surface of the vaccine organisms. These markers are called antigens. It takes our immune system roughly two weeks to learn about the vaccine organisms and while this is happening, we might feel tired or develop a sore arm. This is because the immune system is working hard to kill or eliminate all the vaccine organisms. As the vaccine is either a killed or extremely weakened version of the microbes, our immune system can process the vaccine and will not make us ill. By eliminating all the vaccine, the immune system remembers how to combat those microbes. This means that the next time microbes carrying the same markers/antigen enter our body, the immune system is ready to fight it before it has a chance to make us ill. This means we develop immunity against diseases.
What is herd immunity?
Herd immunity is a type of immunity which occurs when the vaccination of a portion of a population (or herd) provides protection to unvaccinated individuals. If enough of a population is vaccinated, unvaccinated individuals are less likely to encounter the disease due to its decreased occurrence. It’s important to maintain herd immunity as some people are unable to have vaccinations.