Let me preface this by saying that vaccines are kind of my jam. My father is a doctor. I believe in science, not conspiracy theories. When a pediatrician has offered one of my kids a vaccine in the past, I have accepted that offer as I would a free upgrade or an extra hour’s sleep: immediately and gratefully. I knew that there were (miniscule) risks, of course, but also that those risks paled in comparison to the risks of the actual diseases the vaccines were preventing. Mumps sounds pretty dreadful, I thought to myself. Let’s get this done.
And so it is with no small amount of hesitation that I admit that when Pfizer recently announced that the company would soon begin testing its vaccine on children as young as five (maybe even as young as six months in the coming weeks), my heart both swelled and sank. As soon as September or October, it seems, my youngsters may be able to go to school without worry, fly to visit grandma with impunity, have birthday parties inside, unmasked, through rain, sleet, snow, and hail. There was cause for much rejoicing.
Yet behind that rejoicing, I’d be lying if I said that there wasn’t also fear. These vaccines are new, without the years or even decades of data to recommend them that so many other vaccines have. And they protect against a disease for which most children don’t have severe symptoms, though a handful are affected gravely.
These fears are compounded by the fact that, like families everywhere, I’ve spent over a year now choosing between a myriad of bad options for my kids. So it’s hard for some parents — even ones, like myself, who got the Covid-19 vaccine the very second we could — to break out of that cycle of worry. “Parents are so tired and have so much decision fatigue,” says Dr. Hina Talib, an associate professor of pediatrics and an adolescent-medicine specialist at Children’s Hospital at Montefiore in New York — and mother of two children under the age of six. “And it’s a very different thing when you’re making a decision for somebody that you’re responsible for — i.e. your child — than when you’re making a decision for yourself. It’s ‘parenting’ defined to worry more about your children.”
So Talib wasn’t surprised when parents didn’t exactly beat down her door to have their teens and tweens vaccinated after the FDA granted Emergency Use Authorization for the Pfizer vaccine in kids ages 12-15. According to a poll published in May by the Kaiser Family Foundation, only 30 percent of parents said they would get their kids vaccinated right away, while 23 percent said they never would. “In the early weeks, I would say that more than half had questions — despite being vaccinated themselves,” Talib says. “They would say, ‘I’m not an anti-vaxxer. I’m not hesitant. I believe in science’… But parents and children together have really experienced this pandemic in a very heavy way. The messaging doesn’t always center children, parents [were] not always top of people’s minds when they were talking about the pandemic, [and] that sort of erupted into this flurry of: ‘I have questions. Is that OK?’ Yes. Yes, it’s OK.”
The question Talib has gotten most consistently is whether the vaccine is safe for bodies that are still growing and changing in dramatic ways. And her answer is another resounding “yes.” For one, we’ve been giving vaccines to growing kids for generations. For another, “The vaccine is developed based on the maturity of the immune system, not the size of the patient,” she says. So the very first stage of trials in kids will be about determining what dose is appropriate to trigger an immune response without too dolorously mimicking symptoms like fever, chills, headache, and muscle pain that can occur from an actual infection, explains Dr. Paul Offit, director of the Vaccine Education Center and an attending physician in the Division of Infectious Diseases at the Children’s Hospital of Philadelphia. (The second stage will be about looking at the efficacy of that immune response in protecting against Covid-19, which in older kids has proven to be very high: Of the nearly 2,300 12-15-year-olds who participated in the Pfizer trial, none of those who got the vaccine came down with Covid, while some of those in the placebo group did.)
Then there are the various rumors to gently dispel — namely, that the vaccines can delay puberty or harm fertility. Talib says the former is based on stories that some women have had longer or delayed periods after getting their shots — a link that she finds both likely and unremarkable. “A lot of things can suppress your menstrual axis, including stress, fever, weight gain, weight loss,” she points out. “And so it’s totally plausible that [the vaccine] may make one period a little wonky. But what we’ve seen is that they normalize after one or two cycles. Altering the course of puberty? No. A fever related to a vaccine isn’t going to do that.”
As for the rumor that the vaccine could harm fertility, it was born out of a misinformation campaign positing that it causes the immune system to attack placentas — a “theory” that has been thoroughly debunked. In fact, during the trials for Pfizer, Moderna, and AstraZeneca — all of which required women to be on birth control — a number of participants still managed to get pregnant anyway, and the rates of miscarriage were higher in all three control groups than they were in the groups that got vaccinated.
Next up on the parental concern checklist is the idea that a newly developed vaccine might have unexpected consequences years or even decades down the road. But Offit says that this isn’t really how these vaccines work. Once inside the body, their components biodegrade quickly — within a matter of days — leaving behind just the immune system’s memory of what had been there. “What you find is that the effect will occur within six weeks of a dose,” says Offit, adding that there isn’t a mechanism by which the vaccine could reappear and wreak havoc later.
As Offit explains it, the effects that could show up within those first six weeks tend to fall into one of three categories. The first is that a child could have an allergic reaction to the components of the vaccine — a rare outcome made even rarer by the fact that Covid-19 vaccines do not contain a live virus. Even more unlikely than an allergic reaction would be a case in which the vaccine causes an autoimmune response, somehow triggering the immune system to begin attacking healthy cells (as with the one-in-a-million chance that the flu vaccine might lead to a case of Guillain-Barré syndrome).
The remaining side effects fall under the umbrella of potential symptoms of the actual infection and can range from common and mild (headache and fever) to rare but severe (blood clots). The CDC has reported that teens aged 12 to 15 have experienced side effects like fever and fatigue more commonly than people 16 and over. And recent data has indicated that the Covid vaccine may be causing rare instances of heart inflammation in young men. But heart inflammation, or myocarditis, is yet another symptom that one is far more likely to get from Covid itself than from the Covid vaccine. “Look, there are many viruses that cause myocarditis — that’s already a known thing,” says Talib. “We didn’t plan our lives around that fact pre-pandemic, but it was a fact. So it’s important to keep things in context.” In her mind, these types of potential side effects are actually more of an argument for vaccines rather than against them. “You’re better off catching what you can control, rather than leaving it up to chance.”
These are all outcomes, of course, that the vaccine trials will be looking for carefully, with the understanding that children could react quite differently than their parents do. “Kids aren’t just little adults,” says Dr. Sonja Rasmussen, a 20-year veteran of the CDC and professor in the departments of pediatrics and epidemiology at the University of Florida. For one, their immune systems haven’t been exposed to as many pathogens, so they tend to produce a stronger response to vaccines than adults do. Then again, they also tend to produce a stronger immune response to real infections — which is why they tend to have higher fevers when sick — though this has clearly and mysteriously not been happening in the case of Covid-19. “There’s a paper that summarizes all the possible reasons kids are so mildly affected,” Rasmussen says. “Whenever people give that many possible reasons, it means they really don’t know.”
What vaccine scientists do know is that one of the most serious health risks posed to children from Covid-19, Multisystem Inflammatory Syndrome (MIS-C), is also one of the reasons these vaccines need to be tested so carefully. According to the CDC, roughly 4,000 children have developed MIS-C in the U.S. since the pandemic began. It is characterized by dangerous, and in rare cases deadly, inflammation of organs like the heart, brain, kidneys, and skin. “It seems to be an over-exuberant inflammatory or immune response to the virus,” says Dr. Peter Hotez, a professor of pediatrics and molecular virology and microbiology at Baylor College and co-director of the Texas Children’s Hospital Center for Vaccine Development. “So when you’re building the design of your clinical trials, that’s something you’d specifically try to look at: Would the [vaccine] also trigger an exuberant immune response? Or would you have that effect if someone is vaccinated and they get exposed? These are low probability events, but when you do a vaccine trial, you want to pick up any low probability event. As a pediatric vaccine scientist, you always think, ‘OK, what are the things that could go wrong?’”
Hotez is used to asking that question. The father of an autistic daughter, he has long been a target of the anti-vax movement for very publicly arguing that vaccines weren’t the cause (“That’s what made me public enemy number one with the anti-vaxxers…You’re talking to the OG villain”). He was quick to pick up on the Covid-19 misinformation campaign coming out of the Trump White House, and also quick to point out that although the vaccines seem to have been developed at “warp speed,” really they weren’t: Scientists have been expecting — and preparing for — an event like this for years. “Remember, when the company CEO reads the press release, they’re not meant for you and me, they’re meant for shareholders and tend to spectacularize their accomplishments,” says Hotez. “Those press releases fail to mention that all of that builds on more than a decade of research and development from groups like ours. So this idea that it came out of nowhere is misleading.”
A June 10th meeting of the FDA’s vaccine advisory committee nonetheless found members split over whether Emergency Use Authorization of the Covid vaccine should be granted for younger children this fall — a process that would hasten the approval by three months. Some doctors have argued that the risks of Covid aren’t great enough to young children to justify the sped-up timeline. Others have pointed out that such a view is too narrow: In order to reach herd immunity — which will protect everyone, children as well as the parents they depend on for their wellbeing — we need to give kids the vaccines as soon as possible.
Also of concern is the possibility of variants developing that are even more dangerous for children — an outcome that becomes more likely the more Covid is allowed to spread. After all, viruses tend to evolve to ensure their own survival, and there is some evidence that children are becoming the largest vectors of Covid in areas in which adult vaccination rates are high.
More pointedly, the fact that Covid-19 does not affect children as much as adults does not mean that they are unaffected. Covid fatalities are very rare in kids compared to adults, but the disease reportedly cracked the top ten highest causes of death among children in 2020. Even if kids survive an infection, they can end up with long-lasting effects: A recent study of 129 children found that 27 percent of them still had at least one remaining symptom — from heart palpitations to trouble concentrating — 120 days after being diagnosed. “I take issue when people minimize the health risk of Covid-19 in children,” says Talib. “It is astonishing to me to hear folks say, ‘But it’s only 400 children that died.’ Children are not supposed to die. And when you have a vaccine that can prevent disease, they deserve that.”
Which is why, when the time comes, Talib is sure that she’ll vaccinate her own children. “Once [it’s] approved, meaning it’s shown to be safe and effective for the younger ages, I will treat this vaccine like any other pediatric vaccine that exists to eliminate a disease,” she says. “Yes, I would sign up my littles for the vaccine. But I would also say a prayer right before — for my anxiety but also for my gratitude.”