A federal judge on Monday temporarily blocked Health and Human Services Secretary Robert F. Kennedy Jr. from reducing the number of vaccines recommended for children and ruled that his restructuring of a key vaccine advisory committee likely violated federal law.

Judge Brian E. Murphy's decision halts Kennedy's January order to end broad recommendations for all children to receive vaccinations against influenza, rotavirus, hepatitis A, hepatitis B, certain forms of meningitis, and respiratory syncytial virus (RSV). The ruling came in response to a lawsuit filed by the American Academy of Pediatrics and other medical groups.

The case originally focused on Kennedy's decision to stop recommending COVID-19 vaccinations for most children and pregnant women, but was later expanded to challenge additional policy changes. Medical organizations argued that the vaccine recommendation changes would undermine protections against multiple diseases.

Murphy also addressed Kennedy's reconstitution of the Advisory Committee on Immunization Practices (ACIP), which provides vaccine recommendations to health officials. Kennedy, who was a prominent vaccine critic before becoming health secretary, dismissed the entire 17-member panel and replaced it with a group that includes several individuals with anti-vaccine positions.

The judge ruled that Kennedy's restructuring of ACIP likely violated federal procedures and ordered the appointments and all decisions made by the reformed committee to be placed on hold. As a result, an ACIP meeting scheduled for this week to discuss COVID-19 vaccines and other issues has been postponed.

A Department of Health and Human Services spokesperson said the agency expects the judge's decision to be overturned and characterized it as an attempt to prevent the Trump administration from governing. Judge Murphy was nominated to the federal bench by President Joe Biden.