How HHS, FDA, and CDC Can Influence U.S. Vaccine Policy

With President-elect Donald Trump announcing his intention to nominate Robert F. Kennedy, Jr. as Secretary of Health and Human Services (HHS), and several other nominations expected soon, including for the heads of the Food and Drug Administration (FDA) and Centers for Disease Control and Prevention (CDC), questions have been raised about what influence these appointed health officials have over U.S. vaccine policy. Kennedy, for example, has expressed doubts about the safety and effectiveness of many vaccines, falsely claimed that vaccines are linked to autism, and voiced opposition to vaccine requirements for children, among other policy positions. Does this mean he or other federal officials could change recommendations or remove vaccines from use? Could these officials impose a different set of vaccine requirements for school-age children? To help answer these questions, this policy brief highlights several areas in which HHS, FDA, and CDC have authority to shape U.S. vaccine policy with a specific focus on vaccine approvals and recommendations for the public. Ultimately, while there are limits, federal officials have significant authority to influence and alter vaccine policy, which could affect vaccine availability, views about vaccines, and vaccine use in the U.S. However, this does not include imposing mandates on or changing local vaccination requirements, as those authorities rest with state and local governments.

What Federal Agencies Approve and Recommend Vaccines?

The Department of Health and Human Services (HHS) is the core federal department responsible for improving the health and well-being of Americans. It is headed by a Secretary (a cabinet-level, Senate-confirmed position), and has 13 operating divisions including key federal agencies related to vaccines and vaccination policy in the U.S.:

• The Food and Drug Administration (FDA) oversees review of the safety and efficacy of candidate vaccines, and is authorized to determine whether or not to approve vaccines for use; only vaccines that have been FDA-approved can be legally administered in the U.S. (although FDA can also provide emergency use authorization for select vaccines under certain circumstances, as was done during the COVID-19 pandemic). FDA may also engage in post-market surveillance of approved vaccines to track their safety, effectiveness and/or possible side effects, and revisit approval decisions if new evidence is warranted. FDA is led by a Commissioner, a Senate-confirmed position, who reports to the Secretary of HHS; the office that oversees vaccine approvals at FDA is the Center for Biologics Evaluation and Research (CBER).
• The Centers for Disease Control and Prevention (CDC) is responsible for providing recommendations to the public about when and how to use approved (or authorized) vaccines. This includes issuing the U.S. adult and childhood immunization schedules, which gives guidance on the age(s) when vaccines should be given, the number of doses recommended, timing of doses, and other information. CDC also oversees the Vaccines for Children (VCP) program, which provides free vaccines to Medicaid eligible, uninsured and underinsured children. CDC is headed by a Director who, due to legislation passed by Congress in 2023, is a Senate-confirmed position as of January 2025). Recommendations related to vaccines are determined by the CDC Director, who reports to the Secretary of HHS.
• In addition to FDA and CDC, there are several other federal agencies and programs that play a role in vaccine development and use in the U.S., including: the National Institutes of Health which support basic vaccine research and clinical studies; the Health Resources and Services Administration, which oversees the National Vaccine Injury Compensation Program (VICP) and the Countermeasures Injury Compensation Program (CICP), each of which can compensate individuals determined to have been harmed by vaccinations; and the Center for the Biomedical Advanced Research and Development Authority (BARDA), which promotes development medical countermeasures, including vaccines, for use in public health emergencies.

Importantly, the HHS Secretary oversees these programs, placing them in a crucial position to influence many aspects of federal vaccine policy. For one, under the Public Health Service Act, the HHS Secretary is authorized to establish a National Vaccine Program, which develops a strategic vaccination plan for the nation and coordinates across multiple agencies. The Secretary also has some ability to shift funding, re-organize offices, and make staffing decisions, but only up to a point because major HHS offices and programs are mandated by law and funded through Congressional appropriations. Further, the HHS Secretary generally has the authority to overrule decisions and recommendations of the FDA Commissioner and CDC Director, though this has happened only rarely in the past.

What is the Relationship Between State and Federal Authority on Vaccination Policy?

Despite the important role played by the federal government in vaccine policy, neither HHS nor any other part of the federal government may impose or revoke vaccine requirements for children in school, or enforce other broad vaccine mandates at the national level, with the potential exception of during a declared health emergency (federal courts have been mixed in their decisions regarding the extent of federal authority in these circumstances). Under the U.S. Constitution’s 10^th Amendment’s “police powers” clause, states are granted primary responsibility for enacting and enforcing laws to promote the health, safety, and general welfare of people in their jurisdictions, which includes public health activities generally and (as upheld in multiple Supreme Court and circuit court decisions) vaccine mandates specifically. Therefore, federal guidance on vaccines and recommended vaccine schedules are guidance, not mandates. State and local decision-makers take this information and determine if a vaccine should be required and for what purpose, and whether individuals may opt out of requirements.

How Can HHS Influence Vaccine Approvals and Recommendations?

While the HHS Secretary, FDA Commissioner, and CDC Director cannot impose a national vaccine mandate (outside of a declared public health emergency, and only then under limited circumstances) or revoke existing state and local level vaccine requirements, here are some ways in which they can influence vaccine policy decisions by states, localities, pediatricians, parents, and individuals:

Influencing or Bypassing Federal Advisory Committee Recommendations

The FDA and CDC each have external expert advisory committees that provide important input into vaccine policy decisions. FDA commonly seeks input from the Vaccines and Related Biological Products Advisory Committee (VRBPAC) during vaccine reviews, and the FDA Commissioner uses VRBPAC recommendations when weighing approvals and other regulatory decisions about vaccines. CDC receives input from the Advisory Committee on Immunization Practices (ACIP), which reviews available evidence and makes recommendations to the CDC Director on individual vaccines and immunization schedules for children and adults. In addition, vaccines recommended by ACIP and adopted by CDC for children ages 18 and younger are automatically covered by the Vaccines for Children (VCP) program, and, per a provision of the Affordable Care Act, ACIP recommendations that have been adopted by the CDC must be covered at no cost by most health plans.

Given their roles in informing federal vaccine decisions, it is possible to exert policy influence through changes in the work of these committees. According to the committee charters and existing legal authorities, HHS leaders have the discretion to:

• Determine advisory committee memberships: Members of the VRBPAC are selected by the FDA Commissioner while members of ACIP are selected by the HHS Secretary. Sitting advisory committee members can be replaced at the discretion of the FDA Commissioner and HHS Secretary.
• Terminate or re-work committee charters. Both VRBPAC and ACIP charters require that these committees be terminated after two years, unless they are renewed, and agencies have discretion over whether to do so. Agencies can also re-write the charters that adjust the rules under which the committees function.
• Bypass advisory committee recommendations. The FDA does not have to request input from VRBPAC for vaccine approval decisions; in addition, where recommendations and input are provided, the final decision ultimately rests with the FDA. Similarly, the CDC director makes the decision on whether a vaccine should be recommended to the public and the content of those recommendations and does not have to follow recommendations issued by ACIP. There is precedent for the FDA and CDC breaking with advisory committee recommendations and issuing their own. Moreover, in all cases, the Secretary of HHS has ultimate authority over vaccine approvals and recommendations and can choose to overrule recommendations from the committees and even FDA and/or CDC leadership.

Adjusting Criteria for Vaccine Approvals and Reviews

The FDA Commissioner and CDC Director (and HHS Secretary), as part of their authorities related to vaccines, have discretion over aspects of the review process and can adjust criteria and timelines to aid or hinder vaccine licensing applications and criteria used for approvals and recommendations. For example:

• FDA evaluates the safety and effectiveness of vaccine candidates, as well as their benefits and risks, and whether the manufacturing and facility information assure product quality and consistency before deciding to recommend a vaccine for approval. As such, the agency has discretion over how it evaluates and weighs these criteria, including whether to put in place different or more or less stringent requirements. FDA could potentially speed up or slow down the pace of review, placing candidate vaccines that are high priorities for the Commissioner (and/or HHS Secretary) on a faster track and lower priority vaccines on a slower track. The FDA also help oversee safety surveillance for vaccines currently approved or authorized for use and can require manufacturers to submit post-market safety and effectiveness studies for vaccines. FDA could seek to remove a vaccine from the market if significant safety concerns were to be identified (or other issues such as concerns about manufacturing practices). However, there is a process for doing so and without new information and sufficient evidence of harms or other concerns there would likely be legal challenges to any attempt to remove an existing approved vaccine.
• In addition to reviewing FDA safety, efficacy, and effectiveness data, CDC and ACIP consider several other factors when assessing whether to recommend a vaccine to the public, including disease epidemiology and burden of disease, the quality of evidence reviewed, economic analyses, and implementation issues. The ACIP uses an evidence-based approach, called the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) and develops guidance for evaluating the evidence. This affords some discretion to ACIP committee members, and CDC, in weighing different factors for determining whether to recommend a vaccine, and the public health guidance provided on how best to use a vaccine.
• FDA and CDC also have some discretion over what data are made available about vaccine safety and efficacy. Currently, vaccine safety and efficacy data are made available at different stages of the vaccine review, approval, and recommendation process, as well as after vaccines are in use. Typically, FDA and vaccine manufacturers publicly make available briefing documents used to summarize what is known about vaccine safety and efficacy and to inform decisions for approval or authorization, as was done for COVID-19 vaccines, though some data is not released publicly. This kind of safety and efficacy data are also released by CDC as part of its process for making recommendations to the public, as has been done for influenza and many other vaccines. Further, the U.S. government maintains a database of clinical trial information and results, which relies on investigators and sponsors choosing to submit such information; some, but not all submissions, include study results. Finally, there are a number of government supported vaccine safety systems used to monitor vaccines after approval (or authorization): MedWatch, the Vaccine Adverse Event Reporting System (VAERS), V-safe, the Vaccine Safety Datalink (VSD) and the Clinical Immunization Safety Assessment (CISA) Project, each of which serves different purposes. VAERS, for example, is a “passive” surveillance system, dependent on people submitting their experiences after vaccination and submitted events cannot on their own determine if the event was related to a vaccine. VAERS Data are accessible to the public on the CDC website.

Communicating to the Public

Beyond its role in determining vaccine approvals and recommendations, the federal government plays a critical role in communicating to the public about vaccines, and these communications may influence public behavior. In recent years, particularly in the wake of the COVID-19 pandemic, there has been increased vaccine hesitancy among the public and reduced trust in federal health authorities including the CDC and FDA, and these views have often diverged along partisan lines. As a result, routine vaccination rates have fallen, including among kindergarten age children. Moreover, the number of states allowing for non-medical vaccine exemptions has risen. In some cases, reductions in vaccination coverage have been associated with outbreaks in parts of the country. Should federal officials choose to communicate doubt about vaccine safety and effectiveness, that is not supported by the data, or to not communicate about vaccines, it could provide momentum to state and local authorities seeking to loosen or eliminate school vaccine requirements, and could lead to a growing share of the public choosing not to get vaccinated or not to have their children vaccinated, which could have significant implications for individual and population health.