Vaccination is a simple, safe, and effective way of protecting people against harmful diseases before they come into contact with them. It uses your body’s natural defenses to build resistance to specific infections and makes your immune system stronger.
Vaccines reduce the risk of getting a disease by working with your body’s natural defenses to build protection. Scientists have been developing safe vaccines for decades to ensure effective vaccination.
Vaccines train your immune system to create antibodies, just as it does when it’s exposed to a disease. However, because vaccines contain only killed or weakened forms of germs like viruses or bacteria, they do not cause the disease or put you at risk of its complications.
Most vaccines are given by injection, but some are given orally (by mouth) or sprayed into the nose.
Source: World Health Organization.