CDC Vaccine Lawsuit: AAP Injunction, State Case, and Appeal

The main CDC vaccine lawsuit, American Academy of Pediatrics v. Kennedy, produced a March 16, 2026 preliminary injunction that blocked HHS Secretary Robert F. Kennedy Jr.’s overhaul of the childhood immunization schedule, suspended the 13 newly appointed members of the CDC’s vaccine advisory panel, and restored the pre-2025 federal vaccine recommendations while litigation continues. A separate lawsuit brought by 15 states is moving on a parallel track in California, and the federal government has appealed the Massachusetts ruling to the First Circuit.

What the Lawsuits Are Challenging

Two things sit at the center of the litigation: the shrinking of the childhood vaccine schedule, and the reconstitution of the Advisory Committee on Immunization Practices (ACIP), the expert panel that has guided federal vaccine policy since 1964.

A January 5, 2026 CDC decision memo cut the diseases targeted by routine childhood vaccinations from 17 to 11 and the recommended vaccines from 13 to 7. Six vaccines previously recommended for all children — rotavirus, COVID-19, influenza, hepatitis A, hepatitis B, and meningococcal — were moved to “shared clinical decision making,” meaning no universal recommendation. The HPV recommendation was reduced from two or three doses to one. HHS defended the changes by pointing to Denmark and other peer nations and said the pared-down schedule was meant to address declining public trust. The revision moved forward without review by CDC experts or public hearings through ACIP, following a December 2025 presidential memorandum.¹

In June 2025, Kennedy fired all 17 voting members of ACIP, calling the previous panel a “rubber stamp” with “persistent conflicts of interest.”² He replaced them with 13 new members, including Martin Kulldorff and Robert W. Malone.³ Judge Brian E. Murphy later found that of 15 members Kennedy appointed, only 6 had meaningful vaccine experience, at least 6 had none at all, and 3 had only tangential expertise.⁴

The Main Case: American Academy of Pediatrics v. Kennedy

The central lawsuit was filed on July 7, 2025, in the U.S. District Court for the District of Massachusetts. The original plaintiffs were the American Academy of Pediatrics, the American College of Physicians, the American Public Health Association, the Infectious Diseases Society of America, the Society for Maternal-Fetal Medicine, the Massachusetts Public Health Alliance, and three anonymous pregnant individuals.⁵

The complaint was originally aimed at Kennedy’s May 2025 directive removing COVID-19 vaccine recommendations for pregnant women and healthy children.⁶ As policy changes accelerated, it was amended repeatedly. By February 2026, the fourth amended complaint challenged four separate government actions: the May 2025 COVID directive; the ACIP reconstitution; three 2025 ACIP votes on thimerosal in flu vaccines, COVID-19 recommendations, and the hepatitis B birth dose; and the January 2026 memo revising the childhood schedule.⁷

The plaintiffs’ core theory is that the government violated the Administrative Procedure Act by acting in an “arbitrary and capricious” manner and by skipping the evidence-based process in which ACIP recommendations are supposed to drive schedule changes.⁸ They also alleged that the reconstituted ACIP violated the Federal Advisory Committee Act because it was not “fairly balanced” and lacked required scientific qualifications, and that Kennedy violated 42 U.S.C. § 245(a), which requires the Secretary to conduct evidence-based campaigns to increase vaccine awareness and combat misinformation.⁵ A November 2025 amendment further alleged that new ACIP members had been selected for ideological alignment, that candidates were required to be registered Republicans or independents, and that anyone who had publicly criticized the president or secretary was disqualified.⁹

What the March 2026 Injunction Did

On January 6, 2026, Judge Murphy denied the government’s motions to dismiss, ruling that the plaintiffs had standing and stated plausible claims.⁹ After hearings in February and March, he issued a 45-page ruling on March 16, 2026 granting a preliminary injunction.¹⁰

The order did four things:

Stayed the January 5, 2026 memo overhauling the childhood immunization schedule, reverting federal guidance to pre-2025 recommendations.
Stayed the appointments of the 13 new ACIP members, preventing them from serving.
Stayed all votes taken by the reconstituted ACIP, including the 2025 decisions on COVID-19 vaccines, thimerosal, and the hepatitis B birth dose.
Barred ACIP from holding meetings, since without its members it lacked a quorum.¹¹

Judge Murphy found a “substantial likelihood” that the reconstituted ACIP did not comply with governing law, described the new members as appearing “distinctly unqualified,” and characterized the January 2026 schedule revision as a “technical, procedural failure” and an “abandonment of the technical knowledge and expertise” that ACIP is designed to provide.¹⁰ He also found the plaintiffs “likely to suffer irreparable harm” without an injunction.⁴ The agency, he wrote, “cannot disregard the APA’s requirements simply because they are following the President’s orders.”¹²

Murphy declined to rule on one piece: whether Kennedy’s original May 2025 COVID-19 directive was itself unlawful, finding that challenge may be moot or not properly before the court.¹³ The American Public Health Association, however, reported that the ruling overturned the May 2025 COVID-19 directive and reversed the December 2025 ACIP recommendation on hepatitis B.¹⁴

The Appeal

On April 29, 2026, the Department of Justice filed a notice of appeal to the U.S. Court of Appeals for the First Circuit. The filing was short and did not lay out the government’s arguments.¹⁵ The government seeks to overturn the district court’s decision staying the ACIP member appointments. A scheduling order was issued June 5, 2026, and the government moved to expedite the appeal on June 12. Briefing is ongoing, and no oral argument date had been set as of mid-June 2026.¹⁶

The 15-State Case: Arizona v. Kennedy

A parallel lawsuit was filed on February 24, 2026, in the U.S. District Court for the Northern District of California. State of Arizona v. Kennedy (Case No. 3:26-cv-01609) is assigned to Judge Vince G. Chhabria.¹⁷ The plaintiffs are the attorneys general of Arizona, California, Colorado, Connecticut, Delaware, Maine, Maryland, Michigan, Minnesota, New Jersey, New Mexico, Oregon, Rhode Island, and Wisconsin, joined by Pennsylvania’s governor. Arizona Attorney General Kris Mayes and California Attorney General Rob Bonta serve as co-leads.¹⁸

The states ask the court to declare the ACIP appointments unlawful and vacate them, and to declare the revised immunization schedule unlawful and set it aside.¹⁸ They argue the new appointments violate ACIP’s charter and the Federal Advisory Committee Act, and that the schedule changes rest on flawed comparisons to countries with different health systems and lack new supporting scientific evidence.¹⁹

This case is at an earlier stage than the AAP suit. As of late May 2026, the court had entered a scheduling order and referred the matter to a magistrate judge for discovery. A hearing on the government’s motion to dismiss for lack of standing is scheduled for August 13, 2026, and the California court is coordinating with the Massachusetts proceedings.²⁰

The May 2026 Executive Order

On May 29, 2026, President Trump issued an executive order directing the CDC and ACIP to review a December 2025 HHS scientific assessment recommending the cut from 17 diseases to 11 and to “take any appropriate steps” to update the schedule accordingly. The order also directed executive agencies to align Medicaid, CHIP, and the Vaccines for Children program with whatever ACIP ultimately recommends.²¹

The order has no immediate operational effect. Because ACIP must approve HHS recommendations before the CDC can act on them, and because the March 2026 injunction bars ACIP from meeting, the order cannot be implemented under current conditions. HHS issued a revised ACIP charter on May 19, 2026, broadening membership criteria, but when the panel will next convene is unclear. Jess Steier, CEO of Unbiased Science, called the order’s current effect “rhetorical,” with “no operational teeth right now.”²²

What This Means for Coverage and Provider Liability

Federal law ties insurance coverage requirements, the Vaccines for Children program, and the Vaccine Injury Compensation Program’s liability shield to CDC and ACIP recommendations. When those recommendations shifted in 2025, real questions arose for providers and families.

Kennedy asserted that vaccine administrators who diverged from the new CDC schedule would not be covered by the VICP’s liability protections.¹² The March 2026 injunction eased that pressure: by staying the new schedule and restoring pre-2025 recommendations as the operative federal guidance, it effectively reinstated the legal framework clinicians had been relying on.²³

The Vaccines for Children program, which provides free vaccines to eligible children, has continued to cover all previously recommended vaccines. CDC communications indicated that VFC coverage does not change unless ACIP passes a formal resolution to modify it, and no such resolution has taken effect given the court’s stay of all ACIP votes.²⁴ Private insurers have pledged to continue covering previously recommended vaccines through the end of 2026.¹

The Congressional Research Service noted, in a May 2026 analysis, that the VICP statute does not define what counts as a vaccine “recommended for routine administration,” leaving unclear whether vaccines moved to “shared clinical decision making” would remain covered if the new schedule were ultimately upheld. CRS suggested Congress could clarify that term, codify ACIP’s role and membership qualifications in statute, and define the scope of the liability shield.¹²

Where Things Stand

The March 16, 2026 preliminary injunction remains in effect, keeping the pre-2025 vaccine recommendations as operative federal guidance. The government’s appeal is pending before the First Circuit with briefing underway.¹⁶ The 15-state case in California is on a separate track, with a motion to dismiss hearing set for August 13, 2026.²⁰ The May 2026 executive order attempting to reach the same schedule changes through a different procedural path stays inoperative as long as the injunction prevents ACIP from meeting or voting.²² The First Circuit’s decision on the appeal is likely to be the next major turning point.

1
KFF. The New Federal Vaccine Schedule: What Changed
2
HHS. Kennedy Op-Ed: Restore Public Trust in Vaccines
3
BBC. Kennedy Appoints New Members to Vaccine Advisory Committee
4
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5
Civil Rights Litigation Clearinghouse. American Academy of Pediatrics v. Kennedy
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8
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Fierce Healthcare. Providers Lawsuit Against RFK Now Asks Court to Nullify ACIPs Recent Vaccine Recommendations
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15
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16
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17
Georgetown Law Institute for Constitutional Advocacy and Protection. State of Arizona et al. v. Kennedy et al.
18
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19
BioPharma Dive. 15 States Sue HHS Over Vaccine Schedule Changes
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21
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Association of Immunization Managers. Provider Liability Concerns With Changes to the CDC Childhood Immunization Schedule