Skip to Navigation

Immunization Rates


Estimated vaccination coverage includes children ages 19 to 35 months with four or more doses of diphtheria and tetanus toxoids and pertussis vaccines (DTP), three or more doses of poliovirus vaccine, one or more doses of any measles-containing vaccine, three or more doses of HiB, three or more doses of HepB vaccine, and 1 or more doses of varicella vaccine.  All data is from the National Immunization Survey (NIS), a large, on-going survey of immunization coverage among U.S. pre-school children (19 - 35 months old).

Immunizing children against infectious disease has been a central mission, and a substantial success, for our national public health systems. During the 20th century the United States has seen the incidence of measles, pertussis, and diphtheria fall by more than 98%. This is due primarily to the use of vaccines that immunize children against these illnesses. But many children are still not adequately vaccinated, and levels of disease can be lowered much further.

The senior immunization rates data represent adults aged 65+ who have had a flu shot within the past year and those who have ever had a pneumonia vaccination.

Vaccination of persons at risk for complications from influenza and pneumococcal disease is a key public health strategy for preventing associated morbidity and mortality in the United States. Risk factors include older age and medical conditions that increase the risk for complications from infections.

Data Source: 

Centers for Disease Control's National Immunization Survey

Data Quality Comments: 

The National Immunization Survey (NIS) has been conducted annually since 1994 by the National Immunization Program and the National Center for Health Statistics, Centers for Disease Control and Prevention. The NIS is used to obtain national, state, and selected urban area estimates of vaccination coverage rates for U.S. children between the ages of 19 and 35 months. The NIS is a random digit dialing telephone survey of households with age-eligible children followed by a mail survey of the children's vaccination providers to validate immunization information.

The statistical methodology for estimating vaccination coverage rates for NIS data was changed in 1998. The new methodology facilitates valid statistical analyses of NIS data that appropriately accounts for the survey's complex sampling design. Small differences exist between vaccination coverage estimates appearing in MMWRs published before 1998 and estimates published on this website. All estimates published on this website are calculated using this new methodology.

Potential limitations of NIS include the possible biases associated with exclusion of households without telephones, household nonresponse, and inaccurate reporting from households and small sample sizes for some states. In addition, estimates based on small sample sizes have a larger variance.

Data based on the Behavioral Risk Factor Surveillance System, an ongoing, state-based, random-digit-dialed telephone survey of non-institutionalized civilian adults aged 18 years and older. As with all self-reported sample surveys, BRFSS data might be subject to systematic error resulting from non-coverage (e.g., lower telephone coverage among populations of low socioeconomic status), non-response (e.g., refusal to participate in the survey or to answer specific questions), or measurement (e.g., social desirability or recall bias).

iconPercent of Arizona Children 19-35 Months Who Are Immunized

Loading Data...

iconPercentage of Adults Age 65+ Immunized In Arizona

Loading Data...

Data Source

Centers for Disease Control's National Immunization Survey