It is amazing how a small vial of vaccine can create years of immunity to disease. This is how it works.
Vaccines protect your baby from disease by allowing their body to perform a “practice run” in protecting itself against germs, so if and when the “real” version of the disease appears, their body has already built the defenses it needs to stay healthy.
Whenever your baby becomes sick their body makes infection-fighting antibodies. Once she recovers, these antibodies serve as watchmen for that particular disease, and remain prepared to fight disease should it reappear. Vaccines trigger the same immune response as when the body encounters a disease, but without causing illness.
If left totally to chance, your child’s first exposure to a disease may be from a germ too strong for their tiny body to fight. Before we had vaccines, many kids were hospitalized or died as a result of infectious diseases. The same germs exist today, but now parents have the choice to immunize their children.