Governors Urge CMS to Reinstate Childhood Immunization Measures in Medicaid and CHIP Care Metrics
Governors Public Health Alliance warns decision undermines states’ ability to track vaccination rates and protect children’s health
WASHINGTON, D.C. — The Governors Public Health Alliance (PHA) sent a letter to Centers for Medicare & Medicaid Services (CMS) Administrator Dr. Mehmet Oz urging CMS to reverse its recent decision to remove childhood immunization measures from the Medicaid and Children’s Health Insurance Program (CHIP) Core Sets. Core Sets are the standardized measures states use to track how well Medicaid and CHIP are delivering care, including whether children are receiving recommended vaccines. The letter is available here.
PHA – a nonpartisan coalition founded by 15 governors in October 2025 and representing approximately one-third of the U.S. population – warned that eliminating these measures reduces visibility into vaccination trends for millions of children, limits states’ ability to assess the impact of recent federal vaccine policy changes, and bypasses the standard public process used to generally update the Core Sets.
While CMS has removed these measures from the Core Sets, states represented in the Governors Public Health Alliance will continue tracking childhood immunization data to ensure states have the information needed to protect kids and respond to emerging risks.
“These measures are essential tools that governors and state health leaders rely on to understand vaccination coverage, identify gaps, and protect children’s health. Removing them without state consultation or public input undermines transparency, accountability, and the ability of states to respond effectively to emerging public health risks,” said Angela Botticella, Managing Director of the Governors Public Health Alliance. “States cannot effectively manage Medicaid and CHIP programs without reliable, comparable data. At a time when federal vaccine recommendations are shifting and preventable diseases are resurging, reducing access to this data makes it harder to protect children and communities.”
In the letter, PHA governors raised concern that CMS announced the removal of the childhood immunization measures on December 30, 2025, without advance consultation with states or a public comment period. The Core Sets are typically updated through a structured, evidence-driven process involving state officials, clinicians, public health experts, and other stakeholders that CMS bypassed.
Governors also emphasized that the decision comes at a particularly dangerous moment, as the United States faces a resurgence of vaccine-preventable diseases, including measles. Eliminating standardized reporting on childhood immunization rates reduces states’ ability to track trends across state lines, anticipate outbreaks, and coordinate responses to public health threats that do not respect borders. It is unclear why CMS would make this abrupt and dangerous decision in this moment, as it claims to want to better analyze vaccines. Collection of this sort of information does exactly what HHS has said it wants to do—examine the public health impacts of vaccination.
The Governors Public Health Alliance urged CMS to immediately restore childhood immunization measures to the Child Core Set, reaffirm the importance of transparent, science-based decision-making, and engage states and stakeholders in any future changes to quality measurement.
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About the Governors Public Health Alliance
The Governors Public Health Alliance (PHA) is a nonpartisan coalition of governors working together to strengthen public health systems, protect access to evidence-based care, and coordinate responses to health threats across state lines. Supported by GovAct, the Alliance brings together governors and senior state officials to share best practices, reinforce scientific integrity, and ensure communities receive clear, credible health information. To learn more, go to www.GovsforHealth.org.
About GovAct
Governors Action Alliance (GovAct) is a nonprofit nonpartisan initiative that helps governors work across state lines to champion fundamental freedoms and improve people’s lives. GovAct serves as a centralized platform for collaboration across governors’ offices—incubating, launching, and supporting alliances of governors. These alliances share cutting-edge policy and legal approaches to some of the most challenging and critical issues we face. To learn more, go to www.GovActAlliance.org.