The U.S. federal government, under Health and Human Services Secretary Robert F. Kennedy Jr. and acting CDC Director Jim O'Neill, has enacted a sweeping overhaul of the nation's childhood immunization schedule, effective immediately on January 5, 2026. This unprecedented move reduces the number of vaccines routinely recommended for all children from 17 to 11. Several vaccines, including those for rotavirus, influenza, COVID-19, hepatitis A, hepatitis B, meningococcal disease, and RSV, have been reclassified into 'shared clinical decision-making' categories or recommended only for high-risk groups. The dosage for the HPV vaccine has also been reduced. Officials stated the changes aim to align the U.S. schedule with those of other wealthy nations, particularly Denmark, and to rebuild public trust. However, this decision has been met with widespread condemnation from public health experts and medical organizations. Critics highlight that CDC career staff were 'blindsided,' and the revisions bypassed the standard scientific review process of the Advisory Committee on Immunization Practices (ACIP). Experts argue that 'shared decision-making' for routine childhood vaccines, while seemingly empowering, manufactures uncertainty and places an undue burden on already strained clinicians and parents. Concerns are particularly high for low-income families and those with limited healthcare access, who may face increased barriers to vaccination, potentially leading to lower uptake and a resurgence of preventable diseases. The comparison to Denmark's vaccine schedule is also deemed inappropriate, as Denmark has a smaller, more homogeneous population, universal healthcare, and different disease epidemiology, making its schedule unsuitable for the diverse U.S. context. Despite the policy changes, federal and private insurance plans are expected to continue covering the affected vaccines, at least through 2026.