and (4) The new state Children's Health Insurance Program (CHIP) is emerging in a health plan niche between Medicaid and private insurance (IOM, 1998). The confluence of these changes may eventually sustain and improve immunization rates by increasing access to private health care providers but it is premature to determine how CHIP enrollments will influence immunization coverage rates among disadvantaged families.
As an insurance program, CHIP does not provide for surveillance, population and vaccine monitoring, professional training, or public education efforts that are commonly funded through infrastructure efforts and benefit the community as a whole. CHIP plans are supposed to conform to federal Early and Periodic Screening, Diagnosis, and Treatment (EPSDT) requirements that include the provision of the required immunizations for children. State plans are expected to provide data that hold them accountable for supporting the performance of these services. But CHIP is not expected to monitor levels of vaccine use among the state population as a whole, nor does it have the mandate to provide surveillance for vaccine-related phenomena. Section 317 funds have traditionally supported these efforts in addition to providing direct vaccine purchase and administration services. What remains uncertain, at this time, is the public cost of and need for the population-wide assessment, data surveillance, and education services as states shift increasingly larger shares of the responsibility for direct health services from the public sector to private health care plans. This topic will be a critical component for consideration in the IOM committee's final report.
Certain factors deserve consideration at this time:
Larger numbers of uninsured children are eligible for health care coverage under CHIP but enrollment remains low. Although CHIP makes childhood immunization a basic benefit, the extent to which the program has penetrated the 0–2 age population is unknown at this time. Service utilization patterns have not yet been established or evaluated for new birth cohorts that could provide information about the extent to which these plans are able to meet the immunization needs of eligible families with young children.
Although a few states are monitoring immunization rates for the commercial and the Medicaid managed care programs (e.g., New Jersey, Connecticut, and Massachusetts), no regional or national datasets exist that can reveal the extent to which such individuals enrolled in managed care plans receive one or more immunization services from out-of-network publicly funded providers.
Public health clinics may often provide an important source of immunization services for young children when a family's insurance status is uncertain, interrupted, or limited in coverage.
VFC-eligible families may no longer qualify for vaccine discounts under some non-Medicaid CHIP programs.13 Therefore, the relationship of managed care payment status to access to vaccine services in private medical offices deserves special consideration, particularly if individuals or families who once relied upon VFC in private health care centers are now referred to public health clinics.
Many CHIP plans do not offer continuous service eligibility. If significant numbers of enrollees shift among Medicaid, CHIP, uninsured status, and pri-