Last year, at my daughter Sawyer’s 8-week appointment, the nurse administered her first round of vaccinations. As the needle pricked her skin, she let out a wail. Then we both started crying. Immediately, I questioned my choice to hold her during the shots. Would she lose trust in some lasting way? Hours later, when Sawyer woke up from a nap sobbing uncontrollably for the first time in her life, I started to wonder whether I should have given her the vaccines at all.
My reaction took me by surprise. I had always been pro-vaccination. I’ve been fully vaccinated since birth, and I’d even tried to get into a trial for the then-experimental RSV shot while pregnant. But now that a baby who I had a bone-deep need to protect was here, I felt like I couldn’t take anything for granted.
During my research of vaccine side effects before bringing her in for her shots, it seemed like the most reliable sources—the Centers for Disease Control and Prevention (CDC), Nemours KidsHealth, Mayo Clinic, etc.—returned a version of the same blanket statement: “Vaccines are safe and effective.” Yet, when we returned to the doctor’s for Sawyer’s next round of shots, the nurse asked if she’d had a negative reaction to previous vaccines. Did hours of crying qualify as negative? Were there other more serious reactions I needed to be worried about? At the same time, because vaccinations have become such a lightning rod, I was nervous to voice my reservations.
Today, my daughter is now more than a year old and with hindsight, I realize that all of this—her reaction to the poke, the fever, my emotional turmoil—was entirely normal.
Still, the experience gave me compassion for the rapidly growing group of parents who question the drumbeat of “safe and effective,” According to a recent Gallup poll, the percentage of Americans who say vaccinating children is “very important” or “extremely important” has plummeted from 94% in 2001 to 69% in 2024. What’s more, the Kaiser Family Foundation has found that parents are more likely than other adults to believe that the measles vaccine is more dangerous than the infection itself.
Clearly, I’m not the only parent out here with anxieties around childhood vaccines, but does arming caregivers with more detailed information really reduce vulnerability to conspiracy theories?
Children Receive a Lot Of Vaccines — Because There Are a Lot Of Diseases to Protect Them Against
Within their first year of life, it’s recommended that children receive vaccinations for approximately 12 different viruses. That means babies are receiving more immunizations from birth to 15 months then they will at any other stage of life.
Recommendations vary slightly, but a typical schedule, as recommended by the CDC, looks like this:
It’s critical to note that a robust vaccine schedule, which first rolled out in the late 1940s (smallpox, diphtheria, tetanus, and pertussis) and eventually evolved to encompass additional diseases, has helped to lower infant and childhood mortality dramatically. In 1935, a stunning 1 out of every 16 children did not live to see their first birthday. Today, the infant mortality rateis 0.56 percent, or one out of every 179 children.
Ross Newman, M.D., FAAP, a pediatrician based in Eugene, Ore., believes much of the vaccine skepticism stems from a lack of knowledge about how devastating diseases like whooping cough, measles, and tuberculosis can be. “People have forgotten what it was like a hundred years ago to raise children in an era before vaccines,” he says. “We’re like in a zombie apocalypse. We’re sitting in this safe little mecca of safety, but right behind those walls there are tons of zombies we can’t see.”
We know that when a large number of people opt out of vaccines, and herd immunity (which is when enough people are immune to a disease that it prevens it from spreading from one person to another), declines, these diseases can surge back. For example, in 2018, two Samoan nurses incorrectly prepared MMR vaccines, fatally poisoning two infants. The nurses were later jailed, but the tragedy caused vaccine rates in Samoa to plummet. The very next year, measles, which had previously been nearly eradicated, came back in full force, claiming the lives of 83 people (the majority of whom were children under age 5) within just 3.5 months.
Even still, memories of outbreaks are fleeting, and reduced incidence of disease can create a space where parents begin to wonder: Is this really necessary if the risk of contracting the disease is so low?
“The herd” is abstract, while for parents, the health of their child is very real.
Vaccine Side Effects: Oversimplified and Hard to Find
Like most life-saving medications vaccines are medical breakthroughs and they come with side effects. However, as a parent, I found it more difficult than I expected to suss out the risks.
Upon doing a Google search, the top trusted results on “vaccines side effects for babies” lean very heavily toward reassurance. Consider how a top-ranked article from the Mayo Clinic discusses children’s vaccine side effects: “Most vaccine side effects are not dangerous…The benefits of getting a vaccine are much greater than the possible side effects for almost all children.”
Contrast this with the Mayo Clinic’s page on iron supplements, acetaminophen, or vitamin D—all of which straightforwardly list two dozen-plus side effects that range from common to rare.
Vaccines, of course, differ from vitamins or medications in that their effects go beyond the individual; you’re protecting the “herd,” not just one child. “When you’re making public health decisions, you’re making a decision for the 99%, not the 1%,” says Dr. Newman.
“It’s really difficult because vaccines do have side effects,” says Justin Rosati, M.D., a pediatric neurologist and assistant professor at the University of Rochester. “The most common being fever and injection site pain, and the most serious that we worry about is anaphylaxis [severe allergic reaction].” Reaction rates depend on the particular vaccine. For example, the likelihood of fever ranges from 3 percent for Hepatitis B to 25 percent for DTaP.
Dr. Newman adds that in rare cases, the vaccine can cause an immune reaction similar to the disease. “For example, one in a million people who get the DTaP vaccine [a combination vaccine that protects against diphtheria, tetanus, and pertussis] might have some swelling around the brain,” he says. (Brain swelling can be a symptom of pertussis)
Outside of fever, pain, and allergic reaction/anaphylaxis, notable side effects of vaccines typically administered to children include:
Hepatitis B: In rare cases, infants can experience a hypotonic-hyporesponsive episode (HHE) in which they become pale, limp, and unresponsive for up to 48 hours following the vaccine. This requires medical attention, however, there are no known long-term effects of HHE.
Rotavirus (RV): One in 100,000 children who receive the rotavirus vaccine may suffer from intussusception (intestinal blockage) within a week after receiving the first or second dose.
Diphtheria, tetanus, & acellular pertussis (DTaP): About one in 10,000 children who received this combination vaccine will experience a severe reaction such as high fever, fever-induced seizures, HHE, or inconsolable crying in due to the occurrence of the pertussis vaccine specifically.(Interestingly, my daughter’s inconsolable crying episode occurred after her first dose of DTaP).There is also a 1–10 in 1 million risk of encephalitis (swelling of the brain).
Flu: Vaccines for influenza vary year to year, but there is a small (one in 1 million) chance of experiencing Guillain-Barré syndrome (GBS), an autoimmune disease which can lead to paralysis. The risk is likely even smaller in infants, as GBS is more common in older adults.
COVID-19: One in 50,000 people have experienced myocarditis (inflammation of the heart) after receiving the vaccine, however, this has largely occurred in young men (not infants).
Measles, mumps and rubella (MMR): There is a 1 in 3,000–4,000 risk of fever-induced seizure, and some children also can experience a measles-like rash. There is a 1 in 1,000,000 risk of encephalitis (brain swelling), as well.
Respiratory syncytial virus (RSV): In trials, vaccine recipients aged 60+ had a slight increased risk of atrial fibrillation. This was not noted in infants.
Vaccine Misinformation and Why It Persists
While vaccine side effects are real, there are a number of narratives that muddy the waters and lead to further confusion. Misinformation on social media is a primary driver—and the Kaiser Family Foundation, a nonprofit known for providing nonpartisan, data-driven research, has found that inaccurate information about vaccines spreads online just as easily as facts.
Here is some of the most cited misinformation—and the actual science:
Vaccines cause autism. It has been proven many times over that there’s no discernable link between childhood vaccines and autism, and still, this narrative persists. In 1998, The Lancet published a study that falsely linked autism to the MMR vaccine. The study was retracted after it was found to be based on scientific misconduct and the author (Andrew Wakefield) was de-licensed. “Once these things get out in the culture, it’s hard to reel them in,” says Dr. Rosati. In the years following Wakefield’s report, celebrities with a wide reach like Jenny McCarthy and Jim Carrey added fuel to the fire—and shows like “The Oprah Winfrey Show” and “Good Morning America” helped these public figures spread dubious claims. A growing distrust of institutions and the fact that the rate of autism has risen but the cause has not been found may have also helped this narrative maintain a stronghold. D. Rosati adds that because childhood vaccines are administered every 3 to 6 months, the timing of an autism diagnosis can mistakenly seem linked to these frequently occurring vaccinations.
Certain formulas have a dangerously high aluminum content. Some vaccines do contain aluminum, which acts as an adjuvant, a substance added to help trigger the appropriate immune response. “Aluminum is one of the main metals that appears in the crust of our earth—it’s literally everywhere,” says Dr. Newman, explaining the aluminum in vaccines is far below the toxicity threshold. “There’s much less aluminum in vaccines than you’d get just by drinking breast milk.”
There’s no reason babies should receive the hepatitis B vaccine if their parents are negative. Since hepatitis B is most often transmitted through bodily fluids, some people believe it’s unnecessary to vaccinate infants—but that’s not true. For many infants who contract hepatitis B, neither parent is positive, the transmission is unknown, and the complications are often life-long.
Natural immunity is better. “The data is mixed on whether natural immunity is longer lasting,” says Dr. Rosati. “But there is a caveat to that because in order to get natural immunity, you have to get sick. If you get sick with polio, you can get paralysis. With hepatitis B, you can get cirrhosis— so you’re putting yourself at risk for all of those things if you do get infected.”
Changing the Vaccine Narrative: Less Persuasion, More Transparency
If you feel as though the debate around vaccines spiked during the pandemic, you’re not alone. Medical professionals were slow to explain public health recommendations around COVID-19, notes Dr. Rosati, who connects that lagging explanation to a spike in vaccine hesitancy in general.
“There was this thought that [the anti-vaccine movement] was on the margins, and scientists and medical professionals didn’t think it was that big of a deal. Then during the COVID-19 pandemic, everything blew up,” he says.”
There’s a natural tension between public health (which focuses on an entire population) and healthcare (which centers on an individual patient)—and vaccines, which serve both ends, are always going to fall into a messy middle thanks to split priorities. For public health authorities, part of the job is to guide individuals to do what’s best for the population. However, it seems clear that when it comes to childhood vaccines, the tactics are falling short.
One possible remedy: less obvious persuasion and clearer transparency around the benefits and risks.
The CDC may want to consider this strategy sooner rather than later. When contacted for this article, the government agency failed to respond to questions around whether blanket messaging on vaccines could contribute to skepticism and instead sent a simple boilerplate statement: “Making sure that children and adolescents are up to date with all recommended vaccines can help keep kids healthy, in school, and ready to learn… Vaccines, like medicine, can have some side effects, but most people who get vaccinated have only mild side effects or none at all.”
For parents struggling with getting all of the information they need to guide a decision around childhood vaccinations, both Dr. Newsom and Dr. Rosati recommend having a direct conversation with your child’s pediatrician about specific concerns. It may also help to get multiple opinions or connect with a specialist, adds Dr. Rosati. As a pediatric neurologist, he says, “I don’t actually give vaccines so I feel like I’m unbiased in that way and can look at parents’ concerns and point them in the right direction.”
As a journalist who focuses on health and as a new mother, I would argue that more direct information about vaccine side effects will have a positive effect. The ability to access facts could enable parents to feel more empowered in their decision making. It may also alleviate the feeling of being pushed to take action—which can make people be more inclined to dig their heels in, or do their own research—a path that often leads people to consume harmful misinformation.
Personally, I will continue to vaccinate my child—but I hope we can move toward a world in which having an open dialogue about this decision comes without the stigma, judgment, or polarization that seems to be such a stalwart of the current climate.
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