Immunizations have had an enormous impact on improving the health of children in the United States. Most parents today have never seen first-hand the devastating consequences that vaccine-preventable diseases have on a child, a family, or community. While these diseases are not common in the U.S., they persist around the world. It is important that we continue to protect our children with vaccines because outbreaks of vaccine-preventable diseases like pertussis, mumps, and measles can and do occur in this country. Vaccination is one of the best ways parents can protect infants, children, and teens from 16 potentially harmful diseases. Vaccine-preventable diseases can be very serious, may require hospitalization, or even be deadly — especially in infants and young children.
Source:  www.cdc.gov