Why does my son or daughter need to be immunized if everyone around us is vaccinated?

This is often referred to as “herd immunity,” which is when a large percentage of the population is vaccinated and immune to disease and protects those who are not. In order for “herd immunity” to be effective in protecting those who cannot be vaccinated, including people being treated for cancers, people who have allergies to vaccine ingredients and some others, all those who can be vaccinated must be.