Which Vaccine?

Emily Oster

9 min Read Emily Oster

Emily Oster

Which Vaccine?

Emily Oster

9 min Read

If you’re a regular reader, you’ll be familiar with my general complaints about pandemic messaging. Put very broadly, I think the public health messaging is too eager to give definite answers when the evidence is still uncertain, and too willing to issue sometimes patronizing platitudes.

This has come up again in the context of comparing across vaccines. The US has now approved three vaccines for COVID-19. The Pfizer and Moderna vaccines are very similar, and have been approved since December. The Johnson and Johnson vaccine (which I will refer to as J&J for short) was only recently approved and is beginning to be rolled out.

The efficacy numbers in the trials of these vaccines differ; J&J is lower. More on what these numbers mean below, but if you look at the top line numbers quoted, this is what you see. At the same time, we are hearing “All the vaccines are awesome!” and “The best vaccines for you is the one you are offered.” This last line worries me especially since I think it runs the risk of suggesting that some people deserve to get a less good vaccine.

So I’d like to dig into this a bit more deeply so we can understand better what we do know, what we don’t yet know, and how to think about the differences across these options.

Before getting into this, I want to reiterate a point I’ve made before. These vaccines will not eliminate COVID-19, at least not for decades. They will also not prevent all cases of symptomatic or asymptomatic illness. They prevent a lot! But, not all. What is most impressive and most important about all of the vaccine options is that they do a great job preventing very serious illness. If we can get to a point where COVID-19 is relatively rare and where people who do get it experience mild symptoms, that will be winning. This is where we are aiming. Not zero COVID.

What is the Difference between Vaccines?

Let’s start with the question of what the difference is between the vaccines. Both the Pfizer/Moderna vaccines and the J&J work through the mechanism of delivering instructions to your cells to manufacture the COVID-19 spike protein. Your immune system then produces antibodies to recognize this spike protein and kill it. If the COVID-19 virus is then introduced to your body, you’re ready for it.

The difference lies in how instructions are delivered. The Pfizer/Moderna vaccines deliver instructions through mRNA, and J&J delivers them through DNA embedded in another type of virus (an inactivated adenovirus which cannot make you sick). An advantage of the DNA delivery mechanism is that DNA is more stable than RNA, which is why the J&J vaccine can be stored at more normal temperatures.

The difference in delivery mechanism opens up the possibility for differences in efficacy. These vaccines work better if they generate a stronger immune response, which will happen if the delivery mechanism is better able to get the virus into your cells. If you’ve already been exposed to the adenovirus used in the J&J vaccine it may work less well (because you’re immune to the delivery vector). On the other hand, the mRNA delivery mode in the Pfizer/Moderna vaccines is new, and it’s possible it works better for some people than others.

Efficacy Numbers

When we talk about efficacy of these vaccines, the first thing we want to run down is — based on what we see in trials — how good a job do the vaccines do at preventing various stages of illness.

The vaccines are all extremely effective at preventing death. The J&J is slightly less effective in the trial data against serious illness and against symptomatic and asymptomatic illness.

It is important to be clear on what these numbers mean. A 95% efficacy does not mean that 5% of people in the trial with the vaccine got symptomatic COVID! What it means is there was a 95% reduction in the risk from the baseline. If your baseline risk of getting serious COVID without the vaccine is, say, 1 in 100 then your risk with the Pfizer or Moderna vaccine is 1 in 2000. With the J&J it would be 1 in 666.

These numbers are all extremely high. Flu vaccines, by contrast, often have efficacy numbers against symptomatic illness that are under 50%. It’s still very useful to have them, but they pale in comparison to any of these options.

Based on the simple table above, it does look like the J&J performs slightly less well. However, we cannot directly conclude this because these were not tested in head to head trials. The conditions under which they were evaluated differed in a number of ways, the most important of which is that the J&J was tested in a period with more variant activity. All of the vaccines are likely to be at least slightly less effective against variants, so this could drive some of the differences (put differently: the Pfizer/Moderna numbers could be a bit lower in the variant space, or the J&J numbers could be higher without the variants).

In addition, although these trials are enormous, there is still statistical noise — error — in their estimates. The data in all trials are consistent with a range of values, so point estimates do not tell the whole story. To really figure out which is “better” (if one is) we’d need to test them head to head in a trial. We might eventually get that, but there isn’t much point at the moment given that all are preforming well.

Bottom line: based on my read of the data and many conversations with people who know a lot of stuff I don’t, I think the J&J is likely to be slightly less effective against symptomatic illness than the others, although I think the differences are smaller than the numbers above.

(What if you’re pregnant or breastfeeding? Basically same deal across all vaccines: they’re not yet formally tested but there is no reason to think they are a problem and getting COVID in pregnancy is risky. See some earlier posts for more on this.)

So, what does that mean for both public health and personal choices?

Public Health Choices

From a public health standpoint, the goal is and should be to vaccinate as many people as possible with any vaccine that we have as fast as possible. Every day we do 2 million or 3 million shots of anything is a good day. If everyone had the J&J vaccine magically, we would be in a totally different world. Given that demand still outstrips supply, the public health value of having more vaccines available can hardly be overstated.

The J&J is also incredibly useful for public health because of the one-shot-easy-storage nature. Many states are talking about using it to vaccinate people who come to the ER, or take mobile vaccine clinics to homeless encampments or other difficult to reach populations. These groups are harder to serve with vaccines which require two doses.

From a public health standpoint, this approach is smart, but I will admit to some concern that this will exacerbate the “this is the less good vaccine” view. In fact, the use in these populations has nothing to do with vaccine quality and everything to do with the ease of use. If I were in charge (which I am decidedly not) I would consider also using the J&J on other “transient” populations with less of a stigma. My choice might be on campus college students: mass one-shot vaccination before they leave for the summer.

Bottom line: states should use every last vaccine they get ASAP.

Personal Choices

A lot of people are thinking about this more as a personal choice, though. With the frame of something like: Should I get the J&J if offered, or should I wait for one of the others?

It might be easier to tell you how I’m thinking about it.

My number one point is that I would get any vaccine offered. I’m teaching in person and we’ve had outbreaks and even though I understand my personal risks are small, I’d feel better if I were vaccinated. If someone told me I could get the J&J today, I would stop writing and cooking stuffed shells right now and go get it. Honestly, I’d probably get the Russian Sputnick V vaccine if it was offered. Novavax? Sure. I’m not giving a way my shot, is my point.

And importantly, I would consider myself vaccinated regardless of which vaccine I got. Which doesn’t mean hot basement singing parties or taking off my mask in the grocery store, but does mean I’d go to indoor restaurants and feel more comfortable seeing family and friends in my house, without masks. I wouldn’t make these changes differently if I had the J&J rather than the Pfizer/Moderna.

Second point: If a menu of options was in front of me and I got to choose, I’d pick Pfizer or Moderna since I think their efficacy is slightly higher.

Underlying my feelings here is the realization that this is not my last COVID-19 vaccine; it’s not any of ours. We are going to be having boosters for a while, as the virus evolves and vaccines evolve to address variants. If you get the J&J now, you’ll probably end up with another shot in a year, maybe from them, maybe from Moderna or Pfizer, maybe from some other source. This may be an annoying revelation, but I think it also dials down a lot of the importance here. You aren’t committing to some vaccine for life.

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Updated CDC Guidelines for School and Child Care

NO QUARANTINES!!!

Emily Oster

Instagram

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The AAP’s guidelines recommend sleeping in the same room as your baby “ideally for the first six months.” However, the risk of SIDS is dramatically lower after four months, and the evidence in favor of the protective effect of room sharing is quite weak (both overall and even more so after four months). There is also growing evidence that infants who sleep in their own room by four months sleep better at four months, better at nine months, and even better at 30 months.

With this in mind, it’s worth asking why this recommendation continues at all — or at least why the AAP doesn’t push it back to four months. They say decreased arousals from sleep are linked to SIDS, which could mean that babies sleeping in their own room is risky. But this link is extremely indirect, and they do not show direct evidence to support it.

According to the data we have, parents should sleep in the same room as a baby for as long as it works for them! Sharing a room with a child may have negative impacts on both child and adult sleep. We should give families more help in navigating these trade-offs and making the decisions that work best for them.

#emilyoster #parentdata #roomsharing #sids #parentingguide

The AAP’s guidelines recommend sleeping in the same room as your baby “ideally for the first six months.” However, the risk of SIDS is dramatically lower after four months, and the evidence in favor of the protective effect of room sharing is quite weak (both overall and even more so after four months). There is also growing evidence that infants who sleep in their own room by four months sleep better at four months, better at nine months, and even better at 30 months.

With this in mind, it’s worth asking why this recommendation continues at all — or at least why the AAP doesn’t push it back to four months. They say decreased arousals from sleep are linked to SIDS, which could mean that babies sleeping in their own room is risky. But this link is extremely indirect, and they do not show direct evidence to support it.

According to the data we have, parents should sleep in the same room as a baby for as long as it works for them! Sharing a room with a child may have negative impacts on both child and adult sleep. We should give families more help in navigating these trade-offs and making the decisions that work best for them.

#emilyoster #parentdata #roomsharing #sids #parentingguide
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It was an absolute pleasure to be featured on the @tamronhallshow! We talked about all things data-driven parenting and, in this clip, what I call the plague of secret parenting. To balance having a career and having a family, we can’t hide the fact that we’re parents. If mothers and fathers at the top can speak more openly about child-care obligations, it will help us all set a new precedent.

Watch the full segment at the link in my bio 🔗

#tamronhall #tamronhallshow #emilyoster #parentingsupport #workingparents

It was an absolute pleasure to be featured on the @tamronhallshow! We talked about all things data-driven parenting and, in this clip, what I call the plague of secret parenting. To balance having a career and having a family, we can’t hide the fact that we’re parents. If mothers and fathers at the top can speak more openly about child-care obligations, it will help us all set a new precedent.

Watch the full segment at the link in my bio 🔗

#tamronhall #tamronhallshow #emilyoster #parentingsupport #workingparents
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Invisible labor. It’s the work — in our households especially — that has to happen but that no one sees. It’s making the doctor’s appointment, ensuring birthday cards are purchased, remembering the milk.

My guest on this episode, @everodsky, has come up with a solution here, or at least a way for us to recognize the problem and make our own solutions. I’ve wanted to speak with Eve for ages, since I read her book Fair Play. We had a great conversation about the division of household labor, one I think you’ll get a lot out of!

Listen and subscribe to ParentData with Emily Oster in your favorite podcast app 🎧

#emilyoster #parentdata #parentdatapodcast #parentingpodcast #householdtips #fairplay #invisiblelabor

Invisible labor. It’s the work — in our households especially — that has to happen but that no one sees. It’s making the doctor’s appointment, ensuring birthday cards are purchased, remembering the milk.

My guest on this episode, @everodsky, has come up with a solution here, or at least a way for us to recognize the problem and make our own solutions. I’ve wanted to speak with Eve for ages, since I read her book Fair Play. We had a great conversation about the division of household labor, one I think you’ll get a lot out of!

Listen and subscribe to ParentData with Emily Oster in your favorite podcast app 🎧

#emilyoster #parentdata #parentdatapodcast #parentingpodcast #householdtips #fairplay #invisiblelabor
...

Prenatal vitamins 💊 If there is any product that seems designed to prey on our fears, it’s this one. You’re newly pregnant and you want to do it right. Everyone agrees you need prenatal vitamins, so you get them. But do you want to be that person who just… buys the generic prenatal vitamins?

Good news: fancier vitamins are not better.  Folic acid is the most important prenatal ingredient. Iron (with vitamin C) and DHA are also nice to have. Other included ingredients have only weak or no evidence to support their use. (If you do not consume animal products, add B12, plus a few others depending on your diet.)

Vitamins are just vitamins. Any prenatal vitamin that contains these is enough. 

Comment “Link” for a DM to an article with everything you need to know about prenatal vitamins.

#emilyoster #parentdata #prenatalvitamins #pregnancydiet #pregnancytips

Prenatal vitamins 💊 If there is any product that seems designed to prey on our fears, it’s this one. You’re newly pregnant and you want to do it right. Everyone agrees you need prenatal vitamins, so you get them. But do you want to be that person who just… buys the generic prenatal vitamins?

Good news: fancier vitamins are not better. Folic acid is the most important prenatal ingredient. Iron (with vitamin C) and DHA are also nice to have. Other included ingredients have only weak or no evidence to support their use. (If you do not consume animal products, add B12, plus a few others depending on your diet.)

Vitamins are just vitamins. Any prenatal vitamin that contains these is enough.

Comment “Link” for a DM to an article with everything you need to know about prenatal vitamins.

#emilyoster #parentdata #prenatalvitamins #pregnancydiet #pregnancytips
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When it comes to introducing your newborn to the world, timing matters. It’s a good idea to minimize germ exposure in the first 6-8 weeks; after that, it’s inevitable and, very likely, a good idea! This doesn’t mean you need to be trapped inside. The most significant exposure risks are from seeing other people at home — family, etc. These interactions are not infinitely risky, but they do pose more risk than a walk or a trip to the grocery store, since they involve closer interaction. Think simple and make sure everyone is washing their hands before holding the baby. 💛

#parentdata #emilyoster #newborncare #parentingadvice #parentingtips

When it comes to introducing your newborn to the world, timing matters. It’s a good idea to minimize germ exposure in the first 6-8 weeks; after that, it’s inevitable and, very likely, a good idea! This doesn’t mean you need to be trapped inside. The most significant exposure risks are from seeing other people at home — family, etc. These interactions are not infinitely risky, but they do pose more risk than a walk or a trip to the grocery store, since they involve closer interaction. Think simple and make sure everyone is washing their hands before holding the baby. 💛

#parentdata #emilyoster #newborncare #parentingadvice #parentingtips
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The first edition of Hot Flash is out now! Comment “Link” for a DM to learn more about the late-reproductive stage.

There are times when we expect hormonal shifts. Our reproductive lives are bookended by puberty and menopause. We discuss those changes often because they are definitive and dramatic — a first period is something many of us remember clearly. But between ages 13 and 53, our hormones are changing in more subtle ways. During the late-reproductive stage (in your 40s), you can expect a lot of changes in your menstrual cycle, including the length and symptoms you experience throughout. It’s an important time in our lives that is often overlooked!

🔥 Hot Flash from ParentData is a weekly newsletter on navigating your health and hormones in the post-reproductive years. Written by Dr. Gillian Goddard, Hot Flash provides all of the information you need to have a productive, evidence-based conversation about hormonal health with your doctor.

#emilyoster #parentdata #hotflash #perimenopause #womenshealth

The first edition of Hot Flash is out now! Comment “Link” for a DM to learn more about the late-reproductive stage.

There are times when we expect hormonal shifts. Our reproductive lives are bookended by puberty and menopause. We discuss those changes often because they are definitive and dramatic — a first period is something many of us remember clearly. But between ages 13 and 53, our hormones are changing in more subtle ways. During the late-reproductive stage (in your 40s), you can expect a lot of changes in your menstrual cycle, including the length and symptoms you experience throughout. It’s an important time in our lives that is often overlooked!

🔥 Hot Flash from ParentData is a weekly newsletter on navigating your health and hormones in the post-reproductive years. Written by Dr. Gillian Goddard, Hot Flash provides all of the information you need to have a productive, evidence-based conversation about hormonal health with your doctor.

#emilyoster #parentdata #hotflash #perimenopause #womenshealth
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There are plenty of reels telling you how to parent. Plenty of panic headlines saying that “studies show” what’s best for your kid. Even good data, from a trusted source, can send us into a spiral of comparison. But I want you to remember that no one knows your kid better than you. It’s important to absorb the research, but only you will know the approach that works best for you and your child. 💙

Now tell me in the comments: what’s a parenting move you’ve made recently that feels right to you?

#parentingcommunity #parentingsupport #parentingquotes #emilyoster #parentdata

There are plenty of reels telling you how to parent. Plenty of panic headlines saying that “studies show” what’s best for your kid. Even good data, from a trusted source, can send us into a spiral of comparison. But I want you to remember that no one knows your kid better than you. It’s important to absorb the research, but only you will know the approach that works best for you and your child. 💙

Now tell me in the comments: what’s a parenting move you’ve made recently that feels right to you?

#parentingcommunity #parentingsupport #parentingquotes #emilyoster #parentdata
...

Let’s talk about sex (after) baby! Today on the podcast, I was lucky enough to speak with @enagoski about her new book on sexual connection in long-term relationships. Especially after having kids, this is something many people struggle with. Emily tells us to stop worrying about what’s “normal” and focus on pleasure in its many forms.

Listen and subscribe to ParentData with Emily Oster in your favorite podcast app 🎧

#parentdata #parentdatapodcast #emilyoster #emilynagoski #comeasyouare #cometogether #longtermrelationship #intimacy #relationships

Let’s talk about sex (after) baby! Today on the podcast, I was lucky enough to speak with @enagoski about her new book on sexual connection in long-term relationships. Especially after having kids, this is something many people struggle with. Emily tells us to stop worrying about what’s “normal” and focus on pleasure in its many forms.

Listen and subscribe to ParentData with Emily Oster in your favorite podcast app 🎧

#parentdata #parentdatapodcast #emilyoster #emilynagoski #comeasyouare #cometogether #longtermrelationship #intimacy #relationships
...

Ever wondered if you can safely use leftover baby formula? 🍼 The CDC says to throw out unused formula immediately because of the risk of bacterial growth. However, research suggests that bacterial concentrations do not appreciably increase after 3, 12, or even 24 hours at refrigerator temperatures. Good news! This means there’s not a strong data-based reason to throw out formula right away if you store it in the fridge.

Comment “Link” for a DM to an article on another common formula question: should you throw away old formula powder?

#emilyoster #parentdata #babyformula #babyfeeding #parentingstruggles

Ever wondered if you can safely use leftover baby formula? 🍼 The CDC says to throw out unused formula immediately because of the risk of bacterial growth. However, research suggests that bacterial concentrations do not appreciably increase after 3, 12, or even 24 hours at refrigerator temperatures. Good news! This means there’s not a strong data-based reason to throw out formula right away if you store it in the fridge.

Comment “Link” for a DM to an article on another common formula question: should you throw away old formula powder?

#emilyoster #parentdata #babyformula #babyfeeding #parentingstruggles
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What’s the most important piece of advice for new parents? Here’s one answer, but I want to hear from you! Share your suggestions in the comments ⬇️

#emilyoster #parentdata #parentingtips #parentingadvice #newparents #parentingcommunity

What’s the most important piece of advice for new parents? Here’s one answer, but I want to hear from you! Share your suggestions in the comments ⬇️

#emilyoster #parentdata #parentingtips #parentingadvice #newparents #parentingcommunity
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What's in the bag of a Vagina Economist? 👀 Someone please tell me this looks familiar to you.

What`s in the bag of a Vagina Economist? 👀 Someone please tell me this looks familiar to you. ...

Comment ”link” for a DM to learn more about tongue ties 🔗

Breastfeeding is often difficult, especially at the start. For babies with tongue ties, many infants (and their moms) struggle to get the hang of a good latch. This can lead to painful nipples and to inefficient feeding, and then low weight gain.

So what does the data say about the increasingly common practice of cutting tongue-ties in infants to improve breastfeeding success? Several weeks ago, @nytimes published a long and quite scary article on this topic.

After diving into the data, here is what I found. There is limited evidence that frenotomy procedures improve breastfeeding efficacy and the harms of the procedure are minimal. Many women do report that it alleviates pain and helps them with breastfeeding. However, it should not be a first-line treatment for breastfeeding problems.

#parentdata #emilyoster #tonguetie #tonguetiebabies #breastfeedingsupport

Comment ”link” for a DM to learn more about tongue ties 🔗

Breastfeeding is often difficult, especially at the start. For babies with tongue ties, many infants (and their moms) struggle to get the hang of a good latch. This can lead to painful nipples and to inefficient feeding, and then low weight gain.

So what does the data say about the increasingly common practice of cutting tongue-ties in infants to improve breastfeeding success? Several weeks ago, @nytimes published a long and quite scary article on this topic.

After diving into the data, here is what I found. There is limited evidence that frenotomy procedures improve breastfeeding efficacy and the harms of the procedure are minimal. Many women do report that it alleviates pain and helps them with breastfeeding. However, it should not be a first-line treatment for breastfeeding problems.

#parentdata #emilyoster #tonguetie #tonguetiebabies #breastfeedingsupport
...

Tag a friend who needs to hear this 💛 For many choices in parenting, there is no one right answer. We can use research and data to make informed decisions, but ultimately, it won’t tell you what to do. Only you can decide what will be best for your kids and your family.

I’m here to remind you to take a deep breath and trust yourself. I’ll be here to support you along the way. 

Thank you to everyone who submitted videos, including:
@sarah.consoli
@jess_lynn627
@nicolevandenwills
@thedrblair
@ncbenedict29
@haleycimini
@iamkellysnodgrass
@calesse_smith
@garnet__gordon
@jencoopgaiser87
@danigirl18c
@jamielundergreen
@carly_comber
@thecelebratingmama
@emilyannbynum
@eeliz413

#emilyoster #parentdata #parentingadvice #parentingsupport #parentingquotes

Tag a friend who needs to hear this 💛 For many choices in parenting, there is no one right answer. We can use research and data to make informed decisions, but ultimately, it won’t tell you what to do. Only you can decide what will be best for your kids and your family.

I’m here to remind you to take a deep breath and trust yourself. I’ll be here to support you along the way.

Thank you to everyone who submitted videos, including:
@sarah.consoli
@jess_lynn627
@nicolevandenwills
@thedrblair
@ncbenedict29
@haleycimini
@iamkellysnodgrass
@calesse_smith
@garnet__gordon
@jencoopgaiser87
@danigirl18c
@jamielundergreen
@carly_comber
@thecelebratingmama
@emilyannbynum
@eeliz413

#emilyoster #parentdata #parentingadvice #parentingsupport #parentingquotes
...

Congratulations on making it through another year of panic headlines! We’ve had some doozies this year, like aspartame causing cancer and the perils of white noise, but these headlines are very often based on poor data. Correlation does not equal causation. There will certainly be more panic headlines in 2024, but ParentData is here to debunk them for you.

#emilyoster #parentdata #happynewyear2024 #panicheadline #datadriven

Congratulations on making it through another year of panic headlines! We’ve had some doozies this year, like aspartame causing cancer and the perils of white noise, but these headlines are very often based on poor data. Correlation does not equal causation. There will certainly be more panic headlines in 2024, but ParentData is here to debunk them for you.

#emilyoster #parentdata #happynewyear2024 #panicheadline #datadriven
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