As the federal government prepares for the next meeting of its Advisory Committee on Immunization Practices, Health and Human Services Secretary Robert F. Kennedy Jr. is stepping up attacks on the aluminum vaccine component used in many vaccinations to boost the body’s immune response.
Kennedy was a longtime anti-vaccine activist before entering public office. Claims to be aluminum adjuvant It is neurotoxic and has been linked to autism, asthma, and autoimmune diseases. food allergy.
However, science and medicine advance different views. For example, by strongly encouraging parents to introduce peanut-containing foods to infants early on, one drop Incidence of peanut allergy.
Since taking office, President Kennedy has cited aluminum as a top concern and ordered a review of vaccine ingredients. A discussion on “adjuvants and contaminants” is being held by the Vaccine Advisory Committee. draft agenda.
Centers for Disease Control and Prevention web page For years, we have been assured that public vaccines do not cause autism. Updated with new languages on November 19th He said the study did not conclusively rule out a link between vaccines and autism.
He also targeted scientists who published studies showing aluminum adjuvants were safe. In August, President Kennedy denounced: Large Danish study No link was found between aluminum in vaccines and childhood diseases, which we call “.deceptive propaganda stuntThe Annals of Internal Medicine rejected this claim and refused to retract the study.
And regarding future plans, Advisory paneAt the meeting, HHS spokeswoman Emily Hilliard said ACIP is “independently reviewing the entirety of the evidence regarding adjuvants and other vaccine components to ensure the highest safety standards.”
The stakes are high because President Kennedy is questioning aluminum, not just because of its composition. it is part of broader strategy To foster uncertainty about vaccine safety and lay the groundwork for challenging the issue. National Vaccine Injury Compensation Programwhich drugmakers say is essential to ensuring a stable market for the shot.
But researchers in infectious diseases, immunology, pediatrics and epidemiology say the data are clear that aluminum adjuvants are safe.
“Aluminum is the third most abundant element on Earth’s surface,” says Dr. Paul Offit, a pediatrician and director of the Center for Vaccine Education at Children’s Hospital of Philadelphia. “So we’re exposed to aluminum all the time. The water we drink contains aluminum, and the food we eat contains aluminum.”
After the childhood vaccination schedule is complete, vaccines add only a very small amount of aluminum to the body (about 8 milligrams total). Offit said humans naturally ingest about 400 milligrams of aluminum from daily sources during the first 18 years of life.
“I don’t know why there’s so much concern,” said Dr. Rajesh Gupta, a former FDA vaccine scientist. “Aluminum is distributed throughout the body. It is ultimately excreted by the kidneys in the urine. Therefore, aluminum does not stay in the body.”
structure
The aluminum in vaccines is not foil or metal. This is a compound of aluminum salts such as aluminum hydroxide and aluminum phosphate to increase the effectiveness of vaccines.
This is similar to zinc in cold tablets. Rather than swallowing chunks of metal, patients instead ingest zinc salts that dissolve safely in the body.
In vaccines, these aluminum salts provide an additional stimulus to the immune system, allowing it to more effectively recognize target bacteria.
Once injected, the vaccine stays near the injection site and causes a mild, short-term inflammation that summons immune cells. These cells receive vaccine antigens, which are harmless parts of viruses or bacteria, and transport them to nearby lymph nodes. There, an adjuvant makes it look like a wanted poster, allowing the body to quickly identify and destroy the bacteria.
Dr. Harm Hoogenesch, a professor of immunopathology at Purdue University School of Veterinary Medicine, said aluminum adjuvants only work if they are injected in the same location as the vaccine component they are meant to boost, to help nearby immune cells learn to recognize the bacteria. If the two shots are taken in different locations, “you don’t see that effect,” he says.
In response to Kennedy’s claims, scientists say that anything that acts as an adjuvant could, in principle, promote allergic reactions. But that doesn’t mean aluminum-added vaccines turn children into ticking food allergy time bombs. Antigens in vaccines, such as hepatitis B surface antigen and HPV proteins, are not allergens, and food proteins are not included in vaccines.
animal experiment
Animal studies are the basis for Kennedy’s claim that aluminum adjuvants in vaccines can cause allergies. In these experiments, scientists deliberately sensitize rats or mice by injecting them with food proteins mixed with aluminum. Aluminum strengthens the immune response but does not itself cause allergies.
“This is the basis of many experimental mouse models, where you sensitize the mice by injecting them with a food allergen and an aluminum adjuvant,” Hoogenesch said. “We’re not aware of vaccines containing food antigens, so we don’t really know how this could happen.”
Dr. Ross Keddle, a professor of immunology and microbiology at the University of Colorado Anschutz School of Medicine, went further, pointing out that there is no plausible way for a vaccine to cause a peanut allergy in the absence of any vaccine. “Someone would have had to mix peanut protein into the actual vaccine before it was injected.”
Dr. Stefan H.E. Kaufmann, director emeritus of the Max Planck Institute for Infection Biology in Berlin, said that results obtained in mice often do not correspond to those that occur in humans because “mice are much more susceptible to allergic reactions than humans.” In other words, what looks dramatic in rodent studies does not automatically apply to the human immune system.
And in this case, “it’s important to distinguish between how aluminum behaves in laboratory animals and humans,” Kaufman said.
human research
Beyond animal models and theoretical scenarios, scientists have been diligently searching for signs of harm in large human datasets.
In 2023, the study A study by Vaccine Safety Datalink, a collaboration coordinated by the CDC, reported a slight increase in asthma in children younger than 2 years with high aluminum exposure, but that association disappeared on further analysis.
“That paper was roundly criticized,” Offit said. “When we controlled for breastfeeding, the association between asthma and vaccination with aluminum adjuvants disappeared.”
“It should never have been published,” he said.
Dr. Kathy Edwards, professor emeritus of pediatrics at Vanderbilt University, said false signals are common when extracting dozens of results from a large database.
“If you look at 100 different things, some of them may appear to have a signal, based on the law of percentages,” she said. “The whole evaluation of RFK Jr. is really cherry-picking,” she said, adding that “people need some kind of basic understanding of statistics to interpret this.”
Shortly after the results of the 2023 U.S. study gained attention, CDC scientists contacted Dr. Anders Viid, director of epidemiology research at the Statens Serum Institute in Copenhagen, Denmark, to see if his team could replicate the study.
“It makes perfect sense to try to reproduce all kinds of findings with different data sources,” Hviid says.
Hviid national Danish survey Researchers tracked 1.2 million children over 20 years using linked national health registries that record all vaccinations and diagnoses.
“Our health care system is very egalitarian. It’s free, everyone has access to it, and everyone is on this national registry,” he said. Their findings were that there was no increased risk of these symptoms associated with increased amounts of aluminum ingested through vaccines.
rare bump
Doctors have recorded one real reaction to aluminum adjuvant. It is an itchy nodule at the injection site called a “pruritic granuloma.” These small bumps are so rare that most allergists and pediatricians never see a case.
This reaction “doesn’t cause anything bad and has nothing to do with anything other than local inflammation,” Edwards said.
Researchers believe these bumps represent a localized immune reaction (meaning just the area of the injection, not a body-wide allergy), which is very different from the type of immediate allergic reaction treated with antihistamines. These include reactions caused by food or animal damage. In this case, histamine, the body’s own alarm signal, floods the body within minutes, causing hives, swelling, and difficulty breathing. Keddle said the distinction is often lost in public debate.
Removal of aluminum adjuvant
For many experts, the real question is not just whether aluminum is safe, but what will happen to the overall vaccine program if the aluminum adjuvant is removed. Many modern vaccines, such as those for diphtheria and tetanus toxoids, rely on a single purified protein. hepatitis B, and HPV — adjuvants are very important.
Edwards said it’s not practical to simply swap out one adjuvant for another.
“They all kind of build on each other,” she said. Once a vaccine is proven effective and becomes the standard of care, the new or updated version is typically no longer tested against a placebo in the people who should receive it. Instead, it is tested against existing products. This means that each approval builds on the product before it.
Core pediatric vaccines will likely need to be reformulated, and new products will require repeated large-scale clinical trials to prove they are safe and effective. Meanwhile, production gaps and shortages will likely have to be managed for years while manufacturers and regulators start over. whooping coughhepatitis B, and HPV-related cancers have greater scope for further spread.
“Aluminum adjuvants have kind of hit a sweet spot in that they’re effective at inducing strong antibody responses that protect the vaccines that are being used, and they’re also very safe,” Hoogenesch said. “It’s frankly foolish to try to exclude them.”
A century of safe use
The DTaP vaccine, hepatitis B vaccine, and HPV vaccine all contain aluminum adjuvants and have been used for nearly a century. Large studies have shown no association between aluminum and systemic allergic disease.
“We’ve been using aluminum adjuvants in vaccines for decades,” Edwards said. “I have grandchildren. They’ve received all the vaccines. And I’m not worried about their safety.”
Experts warn that if aluminum is wrongly cast as the villain and vaccination rates drop, the consequences are not theoretical. There will be more measles cases in schools, more meningitis cases in college dormitories, and more young people dying from cancers that could have been prevented with HPV vaccination.
In their view, the real danger is not the trace amounts of metals that children already encounter on a daily basis. the Roll back protection Aluminum-adjuvanted vaccines have been available for generations.
That’s the tradeoff Offit hopes parents understand. “Choosing not to get vaccinated is not a risk-free choice,” he said. “It’s just a choice to take a different risk.”
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