Successful control of vaccine-preventable diseases requires more than vaccines.

Immunization is vast and far-reaching. It is a critical clinical preventive service that is recommended across all age groups, and for the healthy, the ill, and the injured. When integrated into children’s primary care, immunization programs have been shown to enhance the performance of other recommended clinical preventive services—such as screening for lead exposure, anemia, and tuberculosis— by bringing children into contact with primary care providers during their most vulnerable years of life. Even though individuals are immunized, people who cannot be immunized because of medical conditions or religious beliefs may also be protected from disease by the ability of most vaccines to interrupt pathogen circulation in a community. The nation’s immunization system was subjected to tremendous changes and improvements during the 1990s. These system changes came from all levels— from multiple federal agencies, from state and local health departments, and from the private health care system. Federal funding for states’ immunization infrastructures rose rapidly to unprecedented levels, then they were gradually reduced. A new entitlement program was created for vaccine purchase, virtually guaranteeing funding for new childhood vaccines added to the schedule for eligible populations. State, federal, and private-sector financing reforms also caused a substantial shift in the delivery of immunizations from public health departments to private-sector primary care providers, 5 resulting in a need for states to further enhance their quality assurance activities. Transition creates challenges and raises important questions. Given the myriad changes and blurring of the private, state, and federal roles, the U.S. Senate’s Appropriations Committee directed the Centers for Disease Control and Prevention (CDC) to contract with the Institute of Medicine (IOM) to conduct an evaluation of the recent successes, resource needs, cost structure, and strategies for immunization efforts in the United States. The work required of IOM was particularly challenging. It required a broad range of expertise, including public health, clinical medicine, health economics, public policy, law, and infectious diseases. The IOM report—Calling the Shots 6 — gives CDC and its immunization partners an unprecedented opportunity to assess challenges and establish priorities for the future of CDC’s program and for the nation’s immunization system. One contribution of IOM’s effort is a conceptual model of the nation’s immunization system. This model follows directly from IOM’s previous efforts that started with the 1988 publication, The Future of Public Health, 7 and continued through to the 1997 publication, Improving Health in the Community. 8 The IOM model depicts the six roles of the nation’s immunization system as a puzzle—all of the pieces need to exist and be properly connected for the whole system to be effective. At the heart of this system is the ultimate reason for the existence of CDC’s National Immunization Program—the control and prevention of infectious diseases. Directly surrounding this fundamental role, are four other key pieces: c assuring the purchase of recommended vaccines for the total population of U.S. children and adults—in particular, vulnerable or higher-risk populations; c assuring access to vaccines within the public sector when private health care services are not adequate to meet local needs; c conducting population-wide surveillance of immunization coverage levels and vaccine safety to identify significant disparities in coverage, gaps in delivery of