Jess Steier, Aimee Pugh Bernard and Amy Gragnolati

Unbiased Science
Confusion around vaccines comes from the sheer volume of conflicting claims people encounter every day. And when misinformation spreads faster than evidence, straightforward explanations become essential. Here, we address common vaccine myths.

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Myth 1: “Too many , too soon.”

​​It’s understandable for parents to wonder whether the recommended schedule exposes infants to “too many” vaccines early in life. But the immune system is built to handle an enormous number of antigens — viruses, bacteria, and other substances that trigger the immune system — at once. And infants encounter far more antigens from everyday activities, such as touching surfaces, breathing, and eating, than they do from vaccines.

The immune system also constantly renews itself. Billions of new lymphocytes, and specifically B cells and T cells, are produced each day. These cells are the ‘special forces’ of the immune system that recognize and respond to pathogens (disease-causing microorganisms). On any given day, the body has trillions of B cells and T cells, each capable of recognizing different pathogens. The sheer capacity of the immune system and the continual turnover of immune cells mean vaccines cannot “overload” or exhaust immune function.

Every new vaccine is tested within the context of the existing schedule to ensure that giving multiple vaccines together is safe and effective. Delaying vaccines doesn’t reduce risk. It simply leaves children unprotected for longer and has been associated with higher rates of vaccine-preventable diseases.

Myth 2: “It’s safer to wait until kids are older.”

The vaccine schedule is designed to protect children before they are likely to be exposed. Providing protection in advance means the immune system is ready if and when a child encounters the pathogen. Waiting until children are older leaves them unprotected during the period when severe disease is most likely to occur.

Delaying vaccines also increases risk for infants who are too young to be vaccinated and for immunocompromised children who rely on high community coverage for protection.

Myth 3: “The schedule is driven by pharma profit.”

Vaccine schedules are created by ACIP (the Advisory Committee on Immunization Practices, an independent panel of medical and public health experts), not vaccine manufacturers. ACIP members cannot work for vaccine companies or hold relevant patents.

​​Additionally, ACIP recommendations are based on peer-reviewed clinical trial data that are publicly available. The meetings where vaccines are discussed and voted on are open to the public and livestreamed, making the decision-making process transparent.

Note: The process described above reflects how ACIP has historically operated. But in June 2025, all ACIP members were removed and replaced with new appointees. The new committee has announced plans to review aspects of the childhood vaccine schedule. Many scientists and medical organizations — including the American Medical Association, American Academy of Pediatrics, and Infectious Diseases Society of America — have raised serious concerns about whether the new committee has the expertise to provide evidence-based guidance.

Myth 4: “Vaccine manufacturers can’t be sued.”

Vaccine companies aren’t exempt from paying the price for wrongdoing. The federal Vaccine Injury Compensation Program (VICP) was created in 1986 to ensure that individuals experiencing rare vaccine injuries can be compensated without affecting vaccine access. From 2006 to 2023 alone, over 5 billion vaccine doses were administered, with about one individual being compensated for every 1 million vaccine doses.

Since the program started, VICP has awarded close to 5.5 billion dollars in total compensation. Importantly, compensation does not require proof that a vaccine caused an injury. Claims are decided on a ‘more likely than not’ standard, ensuring families can receive support even when causation remains scientifically uncertain.

VICP doesn’t protect companies from being prosecuted for wrongdoing. Vaccine manufacturers can still be sued or penalized for negligence, violation of manufacturing standards, or failure to warn of known risks. For example, vaccine manufacturer Chiron had its factory license suspended after its flu vaccine was found to be contaminated in 2004.

Myth 5: “VAERS is proof that vaccines cause harm.”

VAERS (the Vaccine Adverse Event Reporting System) is a monitoring system run by the CDC and FDA. Anyone — including clinicians, manufacturers, and members of the public — can submit a report documenting any health event that occurs after vaccination. The goal is to detect early safety signals, or unusual patterns that might warrant further investigation.

Because anyone can report anything, VAERs data doesn’t show whether a vaccine actually caused the reported event. It captures any health event that occurs after vaccination, even those unrelated to the vaccine itself. A person could report a fever, a rash, or even an injury, such as stubbing a toe, if it occurred after receiving a vaccine.

Determining whether a vaccine actually causes an adverse event requires additional research, such as comparing rates of the event in vaccinated vs. unvaccinated individuals.

Myth 6: “Immunity from infection is better than immunity from vaccines.”

In some cases, immunity from infection may be stronger and longer-lasting compared to immunity from vaccines. But in other cases, this isn’t true — vaccine-induced immunity is actually more protective and longer-lasting against pathogens like human papillomavirus (HPV), Varicella Zoster Virus (VZV, causes chickenpox), and hepatitis B, to name a few. And COVID-19 vaccination has been shown to reduce the risk of long COVID, a benefit that infection alone doesn’t provide.

And regardless, the path to immunity is much safer with vaccines. We can’t predict who will have a mild case of vaccine-preventable diseases and who will become severely ill. Vaccines provide immunity without the risks of the diseases themselves.

Myth 7: “Schedules differ between countries, so they must be arbitrary.”

Schedules differ among countries for various reasons. Vaccine administration timing depends on several factors, including when children in that region face the highest risk. Healthcare access also varies among countries and helps determine the vaccine schedule.

Myth 8: “Aluminum in vaccines is toxic.”

Aluminum salts are used as adjuvants in some vaccines. These are substances that help the immune system respond more effectively.

Injecting aluminum directly does indeed enter the bloodstream, whereas aluminum in food and water is mostly not absorbed. But the amounts in vaccines are far below established safety thresholds, have been shown to be safe, and are formulated so they don’t flood the bloodstream.

Large studies, including a nationwide study in Denmark involving over 1.2 million children, show no association between aluminum-containing vaccines and autoimmune, allergic, or neurodevelopmental conditions.

Myth 9: “Vaccines are linked to autism.”

The concern that vaccines are linked to autism often comes from a place of wanting to understand why autism occurs. But decades of research across multiple countries, researchers, children, and vaccine types all point to the same conclusion: vaccines don’t cause autism.

So why does the myth persist? Partly because autism symptoms often become apparent around the same age at which children receive early childhood vaccines. This can create an illusion of a link, even though a wide range of research doesn’t support this.

Additionally, the original claim connecting the MMR vaccine to autism came from a 1998 paper that was later retracted for ethical violations and scientific wrongdoing. The study involved only 12 children, relied on misrepresented data, and was so deeply flawed that the lead author lost his medical license in the United Kingdom. But by the time it was retracted, the myth had already taken hold.

For information, check out the 20+ studies, reviews, and papers on this topic:

For a detailed analysis of several of these studies, check out this article.

Putting It All Together

Having questions about vaccines doesn’t make someone “anti-vaccine” - it makes them human. We’re all trying to make the best decisions for ourselves and our families, often while sorting through a flood of conflicting information. The goal of this guide is to offer clear, evidence-based answers to the questions people are actually asking.

But accurate information only helps if it reaches people. If you found this useful, please share it - and share credible content from other science communicators doing this work. In a landscape where misinformation spreads fast, sharing evidence-based resources is one of the most powerful things you can do.

If you’d like to support this work, please consider a paid subscription to our Substack. You can also make a tax-deductible donation to The Center for Unbiased Science and Health (CUSH), our nonprofit that funds educational initiatives like this one.

Thank you for reading, for asking questions, and for caring enough to seek out the evidence.

Stay Curious,

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Jess Steier, DrPH, is a public health scientist, host of Unbiased Science, and quirky and empathetic science communicator.
Aimee Pugh Bernard, PhD, is an immunologist, educator, science communicator and science advocate
Amy Gragnolati, PharmD, is a health communicator who delivers clear, useful and evidence-based health information.
 

 
 
 

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