Research examines the growing challenges facing global immunization efforts in the wake of COVID-19
A new article published in Vaccine X highlights how misinformation, policy changes, and funding shortfalls are undermining vaccine confidence, not only for COVID-19 vaccines but also for routine childhood immunizations such as measles, mumps, and rubella (MMR).
The COVID pandemic has highlighted the importance of vaccines in moderating the impact of SARS-CoV-2 virus on the global community. COVID-19 vaccines continue to be utilized internationally, with the primary aim to protect those most at risk of severe disease. The current generation of COVID vaccines do not provide sterilizing immunity, and therefore only have a modest and short-term impact on transmission, which has complicated communication efforts around these vaccines.
Evolving evidence, occasional overstatements by authorities about the impact of vaccines on transmission, and the circulation of misleading claims and disinformation, have complicated public understanding, creating confusion, and in some settings have coincided with lower confidence in vaccines.
Unfortunately, negative perceptions around vaccines are not just confined to COVID-19 vaccines, but also routine childhood vaccines, such as the measles-mumps-rubella (MMR) vaccine. Measles is a highly transmissible, serious viral disease, with increasing case numbers recorded globally over the past few years.
In 2025, the United States reported its first measles death in a decade and the highest number of measles cases in 25 years. Canada, too, is experiencing large outbreaks, with more than 5,100 recent cases and two deaths (as of Oct 27, 2025); and there are high case counts reported in Mexico, Russia, Nigeria, India, Pakistan, and Yemen. Universal efforts are required to maximize protection for those who are most vulnerable.
The independent peer review of immunization science is crucial in providing advice to governments. In the United States, this is via committees such as the Federal Drug Agency's (FDA) Vaccines and Related Biological Products Advisory Committee (VRBPAC), and the Centers for Disease Control and Prevention's (CDC) Advisory Committee on Immunization Practices (ACIP).
Transparency matters to public health practitioners, immunization providers and the broader community. Accordingly, VRPBAC and ACIP meet in open session, with agendas and slide-decks (including from the vaccine manufacturers) available online, as well as full YouTube recordings of the presentations and committee discussions.
Regulatory agencies (and similar national committees) worldwide keep close track of these meetings as they help inform their own deliberations and immunization policy decisions. Any reduction in the integrity of these publicly available, high quality immunization science discussions, such as the FDA VRPBAC, will be felt globally.
The current uncertainty regarding the ACIP in the United States, has recently led professional societies, such as the American Academy of Pediatrics (AAP), to take an unprecedented action and publish their own evidence-based immunization schedule for infants, children, and adolescents.
While this will help support immunization decision-making for pediatricians and the families they care for, this schedule does not cover all of the life course vaccines and may open a pandora's box of different and potentially competing immunization schedules from multiple professional societies. Supporting truly independent and expert National Immunization Technical Advisory Groups (NITAGs) is crucial to help inform policy internationally, with dissemination through groups such as the World Health Organization (WHO) supported Global NITAG Network (GNN).
The current vaccine landscape is also reflective of the support for public health more broadly. Immunization program implementation has been impacted by 2025 United States policy change, including withdrawal of financial support for the WHO and therefore to the deployment of CDC staff traditionally embedded in WHO regional offices. These WHO offices support multiple international public health initiatives, including outbreak response and associated vaccine-preventable disease prevention programs.
Gavi, the Vaccine Alliance, also faces a funding shortfall that will constrain global immunization efforts; with loss of U.S. support complicating Gavi's 2025–2030 replenishment appeal. The funding impact is also disrupting vaccination efforts at UNICEF, who support a broad range of international immunization initiatives for children.
Additionally, the effective closure of USAID—long a major funder of population-based data collection (e.g., DHS) that enables robust estimates of vaccine coverage and zero-dose children at national and sub-national scales—is a substantial loss for global research efforts.
Supporting vaccine safety science is an aim of the Vaccine: X journal and it was recently announced that the U.S. Health and Human Services (HHS) Department is resurrecting the vaccine safety taskforce. It will be important for the taskforce to apply an evidence-based approach to vaccine safety and adverse reaction reporting discussions.
An example is thimerosal and seasonal influenza vaccines for children, pregnant women, and adults, which was discussed at the ACIP meeting in June 2025, with a subsequent recommendation for use of single-dose influenza vaccines free of thimerosal.
As outlined by J. Wise in the BMJ, this decision has the capacity to impact on vaccine confidence, especially since thimerosal (a mercury-containing preservative) is only included in multi-dose vials of seasonal influenza vaccine to minimize the risk of contamination.
There is also no scientific evidence of a link between thiomersal in vaccines and autism, nor any association with neuropsychological delays. The Children's Hospital of Philadelphia Vaccine Education Center has an evidence-based resource outlining the role of thimerosal in vaccines, which is a useful education tool for both health care professionals and families.
Vaccine: X is the open access sister journal to Vaccine and publishes on all aspects of vaccinology and immunization science. Having a journal that is evidence based, peer reviewed, and immediately and permanently accessible, has never been more important. Evidence being utilized appropriately to support immunization policy decision making is crucial, including both the response to vaccine preventable diseases outbreaks (VPDs) such as measles and mumps, as well as assessment of new products such as respiratory syncytial virus (RSV) preventive therapies (including both vaccines and monoclonal antibodies).
The benefits of being an open access journal include:
- Accessibility: Vaccine: X articles are free for anyone to read and download, removing barriers such as paywalls and expensive subscriptions;
- Dissemination: because the articles are accessible they can be more broadly shared via social media, mainstream news etc.;
- Quality: unlike pre-publications they are peer-reviewed;
- Equity: open access helps break down the knowledge gap based on resources, noting publication fees can be a limiting factor, but there are discounts available for publication of articles from lower and middle income countries (LMIC);
- Transparency: open access also encourages peer review of the data and methods, allowing critical appraisal of the methods and results, as well as greater consumer transparency.
Many excellent articles have been published in Vaccine: X, across a broad range of topics related to vaccine-related questions of safety, policy, decision-making, and access, including the importance of "trust" in supporting vaccine acceptance and status updates on the prevention of serious infections such as Dengue.
The Editor and Associate Editors of Vaccine: X encourage ongoing submission of articles to the journal, as the scientific community needs to work together to support having the best data available in the public domain, in a timely manner. This is one way for all of us to try and counter some of the widespread disinformation surrounding vaccines, in an open and transparent way.
More information:
Nigel W. Crawford et al, Open Access in 2025: supporting the publication of readily accessible, 'peer reviewed' immunization science has never been more important, Vaccine: X (2025). DOI: 10.1016/j.jvacx.2025.100745
Provided by Murdoch Children's Research Institute
