​​​​​​​Pediatricians Answer Questions about the COVID-19 Vaccine for Children Ages 5-11

The COVID-19 vaccine is safe, effective and the best way to protect children against severe illness from coronavirus.

Those were the takeaways from a recent “Ask the Pediatricians” virtual Q & A session presented by South Shore Medical Center pediatricians Jeremy Warhaftig, MD and Richard Kauff, MD.

While the recent authorization of Pfizer’s COVID-19 vaccine for children 5-11 came as a relief to parents eager to get their kids the shot, it also raised questions and concerns for many others, who are taking more of a “wait and see” approach.

During the hour-long presentation, Warhaftig, the Chief of Pediatrics at South Shore Medical Center, and Kauff, who has been a pediatrician with the practice for 39 years, fielded a variety of questions – from what was learned through Pfizer’s trials for the age group, to the vaccine’s efficacy and safety, and possible short or long-term side effects in children.

Below, you can find a transcript of both the questions received and answers given by the physicians during the session.

What did the trial data tell us about the Pfizer/BioNTech vaccine for kids?

Warhaftig: The Pfizer study involved roughly 4,400 kids and a 2 to 1 ratio, meaning twice as many got a vaccine as those that got the placebo.

The first phase of the study involved a smaller group of children to figure out what was the right dose to give and still get the same immune response seen in older children and adults. The dose for kids over 12 and adults is 30 micrograms, and it was determined that the best dose for children 5-11 was one-third that amount, 10 micrograms.

The next part of the study was to determine efficacy and safety, with 1,500 kids getting the vaccine and 800 the placebo. Those kids were followed for at least two months after the second dose. In the vaccine group there were three cases of COVID-19, while in the placebo group there were 16 cases.

So, when you do all the math and plug in those numbers, you got about 91% efficacy, which is very good in protecting from symptomatic COVID-19.

Did the children in the vaccine trials experience any major side effects?

Kauff: Young kids tend to do better with vaccines in general. Compared to older kids and adults, they tend to get less side effects. But they were what you would expect. Like other people who had the COVID-19 vaccine, there was fatigue in 39%, a headache for 28%, muscle pain in 12%, and fever or chills in 7%.

There were also a few cases of swollen lymph nodes, usually in the neck, that went away in a week.

We know that those are all things that happen when our immune system is working. If we’re sending a messenger into our body to make our immune system work, we expect as part of the immune system working, to have some of these side effects.

I don’t want to say that a child with a headache or a muscle pain or a fever is a good thing, but at least when that happens, you know that you’re getting a brisk response to the vaccine. And there were no serious reactions.

We also know that that there are no cases in the history of vaccines where people had long-term negative reactions. Reactions to vaccines are usually in the first weeks to two months at the most.

Remember that a vaccine doesn't stay in your body and stand guard and work to fight off the infection.

Think of the vaccine as an email: the body gets this email information and says “well that’s interesting, let me learn from this email” and then the email is deleted. The email deletes itself over the course of 72 hours and there are no remnants of the vaccine remaining.

This mRNA vaccine technology is not brand new. It’s been studied for a least a decade courtesy of the old SARS epidemic, and it’s impossible for it to enter the DNA of the cell. It can’t alter the DNA, so there’s no reason to think the vaccine would give you long-term side effects.

The side effects are there, but they’re mild and self-limited.

Since kids don’t get as sick as adults do with COVID-19, why should my child get vaccinated?

Warhaftig: If we look at the big picture, children don't get as sick as grownups and there have been thankfully fewer bad outcomes in kids.

But COVID-19 is not necessarily a benign illness for kids and we have had about 2 million children in the U.S. fighting the virus. That number probably increased quite a bit during the summer when the delta variant became more prominent.

There have been a lot of hospitalizations from COVID-19 in kids in this age group – the last number I saw was about 8,300. When that happens, about third of those kids end up in the ICU and are very sick.

And it’s not just kids who have risk factors like obesity or a chronic illness like diabetes or a neurological disorder. A third of the kids hospitalized had no risk factors. They were generally healthy kids and still ended up in the hospital.

There's also a complication of COVID-19 that we all worry about quite a bit. It's called Multisystem Inflammatory Syndrome in Children (MIS-C).

That's a type of complication after a child has recovered from their initial COVID-19 infection, or if they were asymptomatic and didn’t even know they had the virus. MIS-C is an illness that involves and can affect multiple organ systems, including the heart and the lungs, the kidneys, the brain, the gastrointestinal tract.

There have been about 5,217 cases of MIS-C since the beginning of October. About 60-70% of those kids are going to end up in an intensive care unit (ICU) and about 1-2% are going to die. And the 5-11 age group is the group with the highest number of cases of MIS-C.

During the pandemic, in our country we’ve had anywhere between 100 to 140 children die from COVID-19. Compared to the huge number of deaths – a quarter of a million people in the U.S. -- that number might not seem high. But that’s still a lot of kids, if you think about all the other childhood illnesses we’re trying to prevent.

If that’s your kid, the stats really don’t matter; that’s a tragedy by any fathom of the imagination regardless of whether it’s from COVID-19, cancer or a car accident. That’s still a horrible thing.

From my standpoint, we have a safe way to protect kids from all those outcomes, that's the reason why vaccination is so important.

Kauff: And to put that in perspective, overall, COVID-19 is the eighth leading cause of death right now in children, and if you track it from the beginning of the delta variant, it’s the sixth highest cause of death in children. I think if we had something that had to do with car seats or some other problem that was the sixth highest cause of death in children, we’d really be looking for a way to prevent it.

And the vaccine is not just to keep kids safe. It’s really to keep the people that your kids love safe – the grandparents, the people with immune deficiency who are vulnerable to the virus.

Because we know that even if kids don’t get sick, just like with the flu and colds, they are really good harbors and spreaders of this virus.

I think we’re getting there with the vaccines, but we’re not quite there. If we can get another 10-15% of the population to have COVID-19 immunity, we can get to the point where we can get back to life as we remember and get these kids in school without masks, which I think we’d like to do.

Warhaftig: I think the point about protecting other people in your house, your relatives and grandparents is a great one. I wasn’t around when we did polio vaccinations in the 1950s, but that was not just about protecting your family. It was really a community effort to protect your community.

That’s a concept that doesn’t always register because we’re in a different world. But protecting our community is huge and we still have to.

Should I be concerned about my child developing myocarditis from the vaccine?

Kauff: Well, as a parent and a pediatrician, I never like to tell parents not to be concerned, because I know I get concerned about everything with my patients and with my own kids, but I think we need to put it in perspective.

If you look up viral myocarditis, if you Google that, it’s a pretty scary illness. Most kids who get viral myocarditis from infection wind up in the hospital, many in the ICU and there are significant numbers of kids who have permanent impairment or die.

Myocarditis post vaccine is a whole different thing. It’s not like viral infection myocarditis. Vaccine myocarditis is almost universally mild.  There have been no deaths and the average recovery is 35 days and the kids are pretty much all recovering 100%.

The last time I looked, in young people between the ages of 12 and 29, there have been 877 cases, which sounds like a lot, but that’s out of 100 million vaccines.

It's certainly more in frequent in males and it’s probably more in older kids. The theory is that there are some hormonal effects, so it seems to be from puberty on that it kicks in. So the expectation is that it’ll have less of an effect on 5-11 year olds.

There were no cases of myocarditis in the trial which is great, but we wouldn’t expect in a trial of 4,400, something that happens much less frequently to occur. I’m not aware of any cases of vaccine-induced myocarditis so far in the 5-11 age group.

If you think about it, everything we do, we’re taking a risk. Everything is risk-benefit. If you’re unvaccinated and you go out in the world, the combination of the risk of getting COVID-19 and the risk of getting myocarditis from COVID-19 is significantly higher than the risk of getting it from the vaccine.

In a way, we're actually protecting kids from myocarditis by giving them the vaccine. Your risk if you are a male of having myocarditis is six times higher if you’re not vaccinated. The risk if you’re a female is 21 times higher.

If you look at things as what are the risks and what are the benefits, it really is safe to do the vaccine – especially including the risk of myocarditis.

The vaccines are new. How do we know there won’t be serious or long-term side effects?

Warhaftig: This goes into an issue we've discussed already on what we know about how long the vaccine stays in our bodies, which is a very short period of time, and what we know about all the other vaccines that we give to kids.

In terms of adverse effects and how long they last, it’s typically within a week or two if that; occasionally it’s up to a month. We don’t have any other vaccines that we give to kids routinely that have long-term side effects. We never see that happen.

So thinking about how the immunology works, we have to use the scientific knowledge that we have and ask is there a plausible mechanism by which this vaccine is going to cause a long-term problem? Everything I’ve read and learned says the answer is no. 

How do we know 100% for sure? We don’t. That’s an impossibility.  How do we get years and years of data when we’re in the middle of this pandemic? We know that by waiting for that data for years, we’re going to have lots of people who get COVID-19 and have adverse outcomes.

And that’s something we really shouldn’t accept.  We want to figure a way to get out of this pandemic and our vaccines are at this moment in time, our safest and most effective way to get us out of this and back to a place that we all want to be.

Do you think children will eventually need booster doses?

Kauff: Yes, and I say that not out of any studies or inside information, but the fact that I was thinking of our vaccination schedule, and I can't think of any of them that are single dose, especially for younger kids.

If you think about coming in for a vaccines, you know the 2-month vaccine is given at 2 months, 4 months, 6 months, again in the second year of life, and again at age 4. The MMR is two doses, the chicken pox is two, and the meningitis is two. So I wouldn't be surprised with young kids to see that there needs to be a booster.

Remember that one of the reasons that we’re giving boosters now to healthy people is to really tamp down the whole pandemic.

Our COVID-19 numbers in Massachusetts are increasing; our numbers nationally are increasing. They're not like they were before and there's not the number of people that are hospitalized and the number of deaths, but we're still in the midst of the pandemic.

It’s also certainly possible as they follow a growing number of kids and look for infections and at the efficacy of the vaccine, it may be that this is enough. It’s possible that we get 6, 9, 12 months down the road and the numbers are much approved because we've done a good job vaccinating and there's very little COVID-19 out there.

I don't think it's going to go away, but if there's very little COVID-19 and kids show us that even if their antibody levels go down and they test positive they’re not getting sick, the decision may be we don’t really have to vaccinate them. Let's wait and watch. The jury's still out and the vaccine has only been out there for three weeks.

It wouldn’t surprise me either way, but if I had to bet a nickel on it, I’d bet on boosters at some point down the road.

Warhaftig: But just to be clear, one dose is not sufficient – kids need to get two doses of the vaccine. The reason for the two doses is this amazing concept called immunologic memory.

And to get that memory response, so our B-cells, which make the antibodies and the T-cells, which regulate everything to get them to really do their thing – you need to get that second dose.

So that's the question, whether down the road kids are going to need a third (booster) dose of a vaccine like adults.

How would you reassure a child who is nervous about getting the shot?

Warhaftig: It depends on the temperament of your child obviously, and that's something where parents know their kids best. I think really focusing a lot on the positive and making them feel like by getting this vaccine they're really doing something special and important.

Invoking things like superheroes and just really emphasizing how important what they're doing is, making this as positive a thing as it can be.

A lot depends on knowing what your child needs. Some kids need to know in advance and you want to give them plenty of advance warning so that they can start to process it.

For other kids that doesn’t work and you maybe don't want to tell them until five minutes before they're getting the vaccine. So I think you have to know you child in terms of how to prepare them best.

Kauff: When we first started talking about COVID-19 back in March of 2020, we were talking about what worried us and how long we thought it would last -- we were really off on that.

But one of the things we were worried about was how in the world were we going to get little kids to wear masks and that’s been the biggest surprise for me; how kids just don’t question it, they just want to do the right thing.

They wear the masks, and I think if we phrase it in a way that this (vaccine) is to keep everyone healthy and keep the people that you love and your friends healthy, I think they’re really going to do well.

I want to get my child vaccinated, but his best friend’s parents aren’t interested in getting their child the shot. Can they still play together safely?

Kauff: That’s a question and answer that comes back to what I was talking about before about your risk tolerance. It certainly is an undeniable benefit to your child playing with their best friend.

I think it depends on a lot of things. If they're going to play outside, I think you're okay if your child's vaccinated.

As we head into the winter, if they're going to go inside, you have to factor in the health of the family members. Is there's anybody who is significantly immunosuppressed in the immediate or extended family?

You know before we had the vaccine for 5-11 year olds, the number one determinant of how many young kids got sick with COVID-19 was the vaccination status of the parents and the people around them. If the friend's parents are vaccinated and you feel that they take the illness seriously, and they take reasonable precautions, you can be on the plus side for playing together.

There's no 100% answer in my view, so it depends on whether they will be inside or outside, the health of the rest of the family, the vaccination status of the best friend, and the habits and behavior of the best friend’s family. Then you have to do the math in your head and make your own decisions.

If they have five best friends and four of them have been vaccinated, I'd say hang with them.

Are there any concerns with the vaccine impacting fertility down the line?

Warhaftig: That’s a tough and really important question. I think that for folks who really are thinking about that question, the best source of good information about that is our colleagues from the American College of Obstetrics and Gynecology. They have some really nice materials on their on their website.

But again, this goes back to how the vaccines work and why a vaccine that's made out of messenger RNA can’t plausibly cause any impact on fertility. The key thing is the messenger RNA doesn’t do anything to our DNA. The DNA is our genetic blueprint that guides everything that happens inside of us, essentially.

The messenger RNA that we get in our vaccines instructs our immune cells to make some spike proteins. The spike proteins are presented to other immune cells called B cells and T cells and that's how it all works. And the messenger RNA is gone after a day or two at most.

So there's not a possible way that these vaccines can impact fertility, the ability of people to get pregnant, or cause any harm while people are pregnant.

But pregnant women are very much at risk from COVID-19 infection. I know we’re getting beyond the scope of what was planned for this talk.  But there is no plausible way that the vaccine should impact your child’s future fertility.

Kauff: And that also reinforces why there’s no reason to believe that there is a risk of long-term side effects from the vaccine, because it doesn’t go into the DNA.  It can’t change the genetic material. And it doesn’t stick around. We have a lot of vaccines that we’ve been using for years and years, and that just doesn’t happen.

So yeah, I think you could wait 10 or 20 years to see if there are long-term side effects with any vaccine.  But then you have 10 or 20 years without the benefit of that vaccine, and that’s really not a good option.

Our pediatricians and all of our physicians who have young kids got this vaccine in the first week that it was available.


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