COVID vaccines for kids: what parents are asking

Today we’re going to do a good old fashioned Q&A session. As a family doctor who cares for people of all ages, I am hearing questions about COVID vaccines for kids multiple times a day from parents and grandparents. There is a lot of excitement about finally being able to protect our younger children. But, the nature of the parental beast is that we also worry. In fact, it is one of our super powers. It serves to help us protect our children in their growing years. But worry, fear, and anxiety can also get in our way. It can paralyze us into inaction – and that inaction can actually increase risk to our children. So today, we are going to tackle those parental worries head on. Let’s talk COVID vaccines for kids: what parents are asking!

1. Does my child really need the vaccine?

  • The short answer is YES!
  • Compared to the COVID suffering of adults, kids tend to fare better. But they are not immune to the dangerous effects of COVID-19. There’s the direct physical effects…
    • Being sick is crummy – 10-14 days of cough, sore throat, headaches, fatigue, fevers, and more (and that’s if it’s a typical case)
    • According to the American Academy of Pediatrics, as of November 5th, over 6.5 million children have tested positive for COVID. And this is likely an undercounting since not everyone goes for testing
    • Among 24 states reporting data, up to 2% of these cases get hospitalized. That works out to 130,000 hospitalized kids
    • There have been >550 pediatric deaths from COVID since the pandemic began
    • As of November 1, there have been 5,526 cases of MIS-C (Multisystem Inflammatory Syndrome in Children). 48 of these have died
  • Then there’s the indirect effects of COVID illness, both individually and in the community
    • Educational days lost due to illness or quarantine during contact tracing
    • Feelings of isolation, loneliness, and increased depression and anxiety
    • Delayed social and emotional development – interaction with others (in school, through sports, at parties/sleepovers, and more) is how kids grow and thrive
    • Potential lost income for parents who have to stay home with sick kids
    • Significant medical costs if a child ends up in the hospital or with long-term medical issues after illness
    • And more… see below

Effects of COVID-19

Infographic discussing effects of COVID-19 on the health of children. Adapted from Pixabay.

  • And don’t forget that kids are little walking vectors of disease. How many times has your 5-11 year old stuck their fingers in their nose or mouth and then touched something? How good are they really about coughing into their elbows and washing hands regularly?
    • Kids can spread COVID to classmates, teachers, parents, grandparents and more
    • Vaccinating helps cut the chain of transmission

2. My child already had COVID and recovered just fine. Why do they need a vaccine?

  • Your child may have some immune protection for a time but that protection seems to fade as time passes
  • If they had COVID illness earlier in the pandemic, they likely did NOT have the Delta strain. Prior infection does not necessarily protect against Delta and we know that Delta is more serious
    • It is better at latching on to our cells and holding tight
    • It is more easily transmitted than earlier strains of virus
  • We have seen people get COVID more than once and not always have a similar or better outcome the second time around
  • Recent studies suggest that vaccines prevent COVID infections much more effectively than prior illness prevents recurrent infection
    • Vaccines were more than 5x more likely to prevent infection than prior COVID illness

3. How many kids were in the Pfizer 5-11 y/o trial?

  • There were 3000 children enrolled in the trial
  • Safety data was gathered from 2250 total participants (1518 receiving vaccine and 750 getting placebo)

4. Is that enough to know about adverse events in kids?

  • It is enough to get a really good sense of the more common side effects of the vaccine
  • Very rare adverse events may only show up once we are administering vaccine to millions of people. But very rare events are just that, VERY RARE
  • Serious adverse effects of vaccines (which are VERY RARE) tend to occur within 6 weeks following immunization. This is why the FDA required Phase 3 trials to have 2 months of follow up before even considering authorization. The trial monitoring will continue for at least 2 years

5. Was the vaccine effective in preventing COVID?

  • Absolutely!
  • The vaccine was 90.7% effective at preventing lab-confirmed symptomatic COVID-19 occurring at least 7 days after dose 2
  • There were NO cases of severe COVID and NO cases of MIS-C in the immunized group
  • And more than that, these trials were conducted during Delta variant predominance. So we know that these vaccines are highly effective in kids against Delta

6. What kind of side effects did kids have after the vaccines and how common were they?

Side effects in Pfizer trial of 5-11 year olds

Percentage of side effects reported after 1st and 2nd doses of Pfizer vaccine in 5-11 year olds

    • Note, nearly all side effects noted in kids were significantly less common than in the comparison group of 16-25 year olds
    • Most of the side effects were listed as “mild” to “moderate”

7. How is the vaccine for kids different than the one for adults?

  • The 5-11 year old dose is 10 mcg (compared to 30 mcg for those 12 and up)
  • This dosing was set after phase 1 trials looking at the effectiveness and tolerability profile of various doses (10, 20, and 30 mcg doses)
  • The 10 mcg dose balanced the best immune response with the fewest side effects
  • The kid version has an improved drug product formulation buffer (this protects it from swings in temperature and will make it easier to store and handle) – improves stability of the vaccine and simplifies administration
  • The pediatric vaccine vial has an ORANGE top to make it clearly different than the adult vaccine vial. The adult vial has a purple top. It is NOT recommended to draw up 1/3 of the adult dose to give to kids

8. Is the smaller dose because of a child’s smaller size? What if I have an 11 year old that is as big as an adult?

  • It’s a good question, but the answer is NO – it’s an age issue not a weight issue
  • The smaller dose has to do with the fact that younger immune systems are more effective at mounting a strong immune response. Evolutionarily, this makes sense, right? Little immune systems have to be really efficient at developing antibodies to protect against all the new antigens (immune stimulating proteins) that kids encounter. If they weren’t really good at mounting immune responses, kids might not survive childhood as well as they do
  • It take less of a dose in kids to trigger the same response we see at higher doses in adults

9. What if my child gets the 5-11 year old dose but, before the 2nd dose, turns 12?

  • Currently, guidance from the Advisory Committee on Immunization Practices (ACIP) says that the dosage of vaccine given should be based on the age of the child on the day of vaccination
  • If a child turns 12 prior to the 2nd dose, the 2nd dose would be the 30 mcg dose
  • However, if a child receives the 10 mcg dose at 11 and then still gets the 10 mcg after turning 12, it is not considered an error. It is still considered a complete series

10. Will there be any long term side effects of the vaccine?

  • Not that we expect
  • Remember, serious adverse events tend to happen within 6 weeks after vaccine administration and none were seen in the trials
  • While COVID vaccines are relatively new for kids, we do have around a year of data on adults. The vaccines have been administered hundreds of millions of times in the US alone. With rare exceptions, we have seen no significant adverse events. And these rare exceptions happened within that 6 week timeframe (myocarditis/pericarditis, for example)
  • We have decades of experience with other vaccines and see NO adverse outcomes that pop up 5, 10, 20 years or more later
  • What DOES crop up later are long-term adverse events from the viruses themselves
    • Measles – in a small percentage of survivors can cause a 100% fatal neurodegenerative condition called Subacute Sclerosing PanEncephalitis (SSPE)
    • Polio – can cause post-polio syndrome decades later
    • Chicken pox – causes a horribly painful blistering rash called Shingles decades later
    • COVID – can cause long-COVID with persistent heart, lung, nervous system, mental health and other effects lasting many months after infection, even in those who only had mild cases. Who knows what it will do decades down the line

11. I’ve heard the mRNA vaccines can affect our DNA?

Double stranded DNA

DNA. Image courtesy of Pixabay

  • This is one of those concerns you can just take right off your worry plate
  • In order for mRNA to affect DNA, two things would have to happen:
    • The RNA would have to get into the nucleus of the cell, where DNA resides – it does not. After transmitting its message to the cell, the mRNA is quickly broken down in the cytoplasm of the cell
    • The vaccines would have to carry Reverse Transcriptase enzymes with them. In nature, messages almost always pass from DNA to RNA and not the other way around. For RNA to pass a message to DNA, the cell has to have Reverse Transcriptase enzymes and these vaccines carry no such things

12. Do COVID vaccines really affect fertility?

  • Nope!
  • The prominent claim being made is this – Because there is a tiny stretch of shared genetic material between the COVID spike protein and a placental protein (called syncytin-1), antibodies to the spike protein will somehow also recognize and attack the placental protein and cause pregnancy failure. PS – if you have a placenta, you are pregnant. Fertility is not your concern
    • The likelihood of this happening is like having two phone numbers that share one digit in common. Calling one number is NOT going to get you the other number, just because of that shared digit
    • Even if this did happen, and it DOESN’T, it would happen after COVID illness as well, right? COVID illness causes our body to develop antibodies to the spike protein. And we’ve had millions and millions of people now infected with COVID and we are not seeing some drastic drop in fertility as a result
  • But what about male fertility? It’s not just a female concern
    • Studies looking at sperm parameters needed for male fertility (sperm count, sperm motility, etc.) have shown NO adverse effects of mRNA vaccination
    • However, COVID illness HAS been shown to negatively affect male fertility Here’s a quote from Urology Times
      • “We know the COVID-19 virus can remain inside the testis long after the initial infection in asymptomatic men. We know the COVID-19 virus can decrease sperm count for up to 3-6 months. And we know the COVID-19 virus can affect the blood vessels and be present in the penis up to 7-9 months after the initial infection and can lead to erectile dysfunction.”

13. What about the heart issues that have been seen with the mRNA vaccines?

  • The myocarditis (inflammation of the heart muscle) and pericarditis (inflammation of the tissue lining the heart) cases seen following mRNA COVID vaccination are rare
    • About 12.6 cases per million second doses of mRNA vaccine
  • They have largely been noted in teen and young adult males, more commonly after the 2nd dose
  • Myocarditis and pericarditis are relatively common at baseline (caused by viruses – LIKE COVID – and others, medications, autoimmune conditions, etc.)
    • It’s important to know that the cases of vaccine-associated myocarditis/pericarditis have been significantly less severe and of shorter duration than those cause by COVID itself
      • A small German study looking at people who recovered from COVID-19 illness showed approximately 75% had evidence of heart involvement on cardiac MRI at a median of 71 days after COVID-19 diagnosis
    • Most vaccine-related cases were mild and have fully recovered
  • There were NO cases noted in kids in the 5-11 year old trials. Though, remember, this was a trial of 3000 kids – we may learn more as we roll the vaccine out to millions of children

14. I’m worried about how fast these vaccines came about. How do we know they are safe?

  • The development of COVID vaccines in record time has been a miracle! But this gives some people reason for pause, worrying that they may have been developed too quickly
    • Rest assured that these vaccines have undergone the EXACT SAME PROCESS of development as all other vaccines we currently have – you can read more about this here
    • These vaccines have had even MORE OVERSIGHT for safety and effectiveness than any other vaccines that have gone before them – read here for more details
    • Real world use, with now more than 430 million doses of COVID vaccine given in the US alone, has shown extremely high vaccine safety and efficacy

15. How do I know that vaccinating my child is the right choice?

COVID vaccines for kids collage

Collage of kids of family doctors (from Physician Moms in Family Medicine Facebook group) getting their COVID vaccines, printed with parental permission

  • Surveys of physicians across the country show that over 96% are fully vaccinated against COVID
  • And these physicians are vaccinating their children as soon as they get the opportunity. While I couldn’t find data on this trend (someone needs to do a survey quick!), anecdotally I can tell you that every single physician and nurse practitioner parent I know has rushed to get their 5-11 year old children vaccinated as soon as the vaccine was available
  • As family doctors and pediatricians, we see the devastating effects of this pandemic on our children. We want this to end just as much as you do. And vaccinating is our fastest way out

16. What can I do to make sure my child’s vaccine experience is being monitored?

  • Enroll your vaccinated child in V-SAFE, the CDC’s active surveillance system for vaccine adverse event monitoring. They will text you daily then weekly then monthly for a period of time after each vaccine. We want to know if there are any concerning safety signals showing up and this is an excellent way to be able to report what your child is experiencing
  • You can register your child for V-SAFE here:


Thanks so much for joining me today. I wish I could reassure everyone in person but, for now, I’ll have to reach you through the airwaves (or whatever drives the Internet). If you have questions I didn’t address, please feel free to leave a message and I’ll do my darnedest to get back to you.


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2 thoughts on “COVID vaccines for kids: what parents are asking”

  1. Thanks for the helpful information!
    Did the trial for children ages 5-11 show that the vaccine prevents death, hospitalizations from COVID, or MIS-C? How was the “90.7% effective” calculated? My understanding was that very few patients in both groups had mild/moderate COVID. Thank you!

    • Hi Kristin,
      Yes, yes, and yes. If you go to the link in the article (—> you can get all the data direct from the source and see how the 90.7% was calculated. We will see the vaccines effectiveness (how it performs in the real world) vs efficacy (how it performs in a trial) as we start to roll it out.
      Thanks for the question!


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