United States in the 1990s, certain problems persist within the national immunization system. These problems include the following:
The need to sustain and document high levels of immunization coverage for a growing number of vaccines delivered within multiple health care settings. Each day sees a new birth cohort of 11,000 infants in the United States, all of whom require routine immunizations in their first 2 years of life. An enormous effort is required in both private and public health care settings to sustain the 1998 level of 79 percent coverage of completion of the recommended immunization series for 2-year-olds across the United States. Improving coverage levels to reach the national goal of 90 percent will be increasingly difficult as new vaccines are added to the recommended schedule and as uncertainties about the benefits of vaccines increase in the absence of visible harm from infectious disease.
Persistent disparities in childhood levels of immunization coverage. The immunization system has successfully reduced racial and ethnic disparities in childhood immunization levels, but coverage levels in areas of concentrated poverty remain significantly lower than national and statewide levels. National surveys reveal a gap of 9 percentage points between children above and below the federal poverty level for the complete series of the most critical childhood vaccines. Significant disparities also persist in coverage rates in many metropolitan areas that have large populations of low-income residents. In some cases, childhood vaccination coverage rates are as much as 19 percent lower for metropolitan residents compared with the remainder of the state.
Low coverage rates and racial and ethnic disparities for adult vaccines. Immunization coverage rates for adults are well below those achieved for childhood immunizations. National immunization levels for influenza vaccines (which are needed annually) have increased to 63 percent (1997) for adults age 65 and older, but levels of pneumococcal vaccination (which is usually a one-time event) among this age group are significantly lower: only 42 percent of noninstitutionalized adults over age 65 had ever received a pneumococcal vaccination by 1997. Coverage rates for high-risk adults who suffer from chronic disease (e.g., heart or lung disease or diabetes) are especially poor (26 percent have received an influenza vaccination, while only 13 percent have received a pneumococcal vaccination). Validated coverage estimates for other adult vaccines (e.g., hepatitis A, hepatitis B, tetanus, and varicella) are severely limited or nonexistent. In addition to low coverage levels, significant racial and ethnic disparities continue to persist in adult immunization levels.
Mortality and morbidity from preventable infectious disease. Between 50,000 and 70,000 adults and about 300 children in the United States die annually from vaccine-preventable diseases or their complications. The