The Healthy People 2010 objective for immunization is to achieve 90 percent coverage for each of the universally recommended vaccines among young children. In 2007, 77.4 percent of children 19-35 months of age had received each of the vaccines in the recommended 4:3:1:3:3:1 series. This series comprises four doses of diphtheria, tetanus, and pertussis vaccine; three doses of poliovirus vaccine; one dose of measles, mumps, and rubella vaccine; three doses of Haemophilus influenzae type b (Hib) vaccine; three doses of the Hepatitis B vaccine; and one dose of varicella (chicken pox) vaccine. Overall, 80.1 percent of young children had received the 4:3:1:3:3 series, which excludes the varicella vaccine.
In recent years, the greatest increase in vaccination rates has occurred with the varicella vaccine, which was added to the recommended schedule in 1996. Since 2000, coverage of varicella vaccine has increased approximately 30 percent. Coverage for most other vaccines has also risen during this time period, generally between 2 and 4 percent.
Racial/ethnic differences in coverage are apparent for most vaccine types. Non-Hispanic Black children have the lowest rates of vaccination with the overall 4:3:1:3:3:1 series, as well as the lowest rates of vaccination with each of the individual vaccines, except varicella.
Each year, the Centers for Disease Control and Prevention publishes an update of the childhood immunization schedule. No new vaccines were added to the schedule in 2009; however, there were a number of changes in the catch-up recommendations for several vaccines and the vaccination guidelines for certain populations of children.