California and Arizona announce legal action against federal vaccine policy

California’s 59th lawsuit against the second Trump administration is focused on recent changes to the federal vaccine schedule that are contrary to decades of scientific research.

State Attorney General Rob Bonta has joined forces with Arizona Attorney General Kris Mayes to sue top Centers for Disease Control (CDC) officials, as well as Health and Human Services (HHS) Secretary Robert F. Kennedy Jr., over the federal changes. The suit, filed in the Northern District of California on Tuesday, claims the changes to the vaccine policy, as well as who made them, are arbitrary to law.

“[Kennedy] and his CDC are flouting decades of scientific research, ignoring credible medical experts and threatening to strain state resources and make America’s children sicker,” Bonta said during a virtual press conference on Tuesday. “Their actions have been unconscionable, illogical and illegal.”

The CDC released a decision memorandum on Jan. 5, announcing the CDC would no longer universally recommend seven vaccines administered in childhood. The seven vaccines protect against rotavirus, meningococcal disease, hepatitis A, hepatitis B, influenza, COVID-19 and respiratory syncytial virus (RSV). 

The 15-state coalition that filed the lawsuit is asking the judge to find the new schedule and the appointment of the current members of the Advisory Committee on Immunization Practices (ACIP) unlawful, and to altogether set aside the schedule and its implementation.

“These vaccines work, they are safe and the science behind them is overwhelming,” Mayes said on Tuesday. “What Secretary Kennedy has done and what the Trump administration has enabled throws science out the window, replaces qualified experts with unqualified ideologues and then uses the resulting confusion to undermine public confidence in vaccines that have saved millions of lives.”

The federal ACIP panel, typically formed of public health experts, guides CDC vaccine policy and recommended the aforementioned for decades. Kennedy recently replaced the previous 17-member ACIP panel with 13 new members, many of whom have expressed anti-vaccine opinions, and whom the multi-state coalition claims “lack the expertise or professional qualifications required for the role.”

Routine childhood vaccinations between 1994 and 2023 prevented 508 million cases of illness, according to a 2024 CDC report. The same vaccine schedule is also responsible for preventing 32 million hospitalizations and over 1.1 million deaths, the report said.

Bonta said Tuesday that Kennedy, a long-time vaccine skeptic, “isn’t entitled to use his opinions as the basis for breaking the law and endangering our children.”

Although many Democratic states, including California and Arizona, are maintaining their stance in support of the previous vaccine schedule, “diseases cross state lines,” Mayes said, making the lawsuit “critical” in stopping the spread of preventable diseases.

The lawsuit claims that, alongside harm to the general public, the vaccine schedule will strain state resources by causing increased Medicaid spending as well as extra expenses relating to combating misinformation and confusion brought about by the CDC’s changing recommendations.

The lawsuit also calls into question the legality of the decision memo itself, given that it was signed off on by then-Acting CDC Director Jim O’Neill, despite there being no formal ACIP recommendation or new scientific findings to back up the demotion of the seven childhood vaccines.

The ACIP panel also voted 8-3 in December to reverse a recommendation that the hepatitis B vaccine be administered at birth, followed by two more doses later on. The vaccine is proven to be up to 90% effective when administered within 24 hours of birth and the recommendation has been in place for close to 30 years.

Mayes said Tuesday the panel is implementing policy based on an "ideological agenda.”

“These changes ignore decades of medical evidence and will lead to outbreaks of diseases we’ve already beaten,” said Governor Gavin Newsom in a prepared statement. “We will not stand by while politics overrides science and endangers our children.”

California is part of the West Coast Health Alliance, a partnership with Oregon, Washington and Hawaii, coordinating public health recommendations guided by experts in the field.