Post-Vaccine Behavior: Can I go Wild?

Emily Oster

9 min Read Emily Oster

Emily Oster

Post-Vaccine Behavior: Can I go Wild?

Emily Oster

9 min Read

Today’s post is all about post-vaccine behavior. In particular: how do things change now that some people have the vaccine, but not all. As of this writing, the NY Times reports 6.7 million people have been vaccinated. The Biden Administration is planning a more aggressive approach, which may speed things up. But: as I’ve said before, it is going to be many months before we will be frolicking unmasked in the meadows or, you know, close talking to strangers at a bar. So the questions pile up: in the intermediate period, what can we or should we do?

Before I get into this, a few quick resources. First, here are my two earlier posts on vaccines (overall & pregnancy). Second, I highly recommend this episode of the Bio Eat World podcast if you want to hear more about the Moderna vaccine, how it was developed and produced. It’s not going to answer these behavior questions, but it’s a great explainer on how these vaccines operate and frankly just how amazing the science is.

The Questions

My wife was vaccinated at work, but I’m not, and the kids aren’t. Is it safe for her to go out unmasked? Or should she still keep masking when she is out so she doesn’t infect us?

My 90-year-old grandmother got the vaccine. Yay! Can she hold her great grand-daughter now? We are dying to introduce them.

I got my second dose!! So did some other friends. Can we all hang out together without masks now?

I actually HAD COVID-19 months ago and I tested positive for antibodies. Is it as if I have the vaccine? Can I hang out unmasked with vaccinated people?

I could go on. But you get the drift. What do vaccines let you do, and what do they not? And beyond that, is vaccine immunity the same as having-had-COVID immunity? Better? Worse?

As usual, I’m going to argue that there are some main underlying principles that will help us answer all of these questions. So let’s dive into those, and then we can come back to some specifics. (Thanks to the COVID-Explained Expert Team for some help here, notably Lindsay Shultz, Susan Johnson and Galit Alter).

Can Vaccinated People Spread COVID?

This is really the big question and I think it’s a confusing one. For many people, the idea is: you’re vaccinated, so you aren’t getting sick. So, how could you spread the virus?

The answer is that the vaccine preps your body to be ready to fight the virus if it is introduced. This means it protects you from getting sick from the virus. The vaccines we have are doing a great job of that. But vaccines do not necessarily protect you from spreading a virus because they don’t prevent you from being infected. In other words, it is possible you’d have asymptomatic infection and pass it on.

This is not just a comment about COVID-19 vaccines. Many or most vaccines have this feature. They provide effective immunity, meaning you do not get sick, but not sterilizing immunity, meaning you can possibly infect others. This is true of the flu vaccine, for example. There are vaccines which give sterilizing immunity, for example HPV and the measles vaccine, but it is not universal by any means.

We do not yet know details about whether and how much COVID-19 vaccination limits your ability to spread the virus. To be clear, there is a lot of reason to think that it would limit your ability to spread at least to some extent. Notably, asymptomatic infections seem to spread less than symptomatic ones. Evidence suggests that asymptomatic people are perhaps 75 or 80% less likely to spread the virus than symptomatic people (see a summary in Nature here, and this meta-analysis on household transmission).

This means the fact that vaccination eliminates symptoms in most people will also mean it reduces spread a lot. Of course, if vaccinated people take fewer precautions, some of this reduction will be cancelled out. Obviously if we could be confident that the vaccine is preventing infection, not just illness, that would be game-changing. But we do not know this yet.

When will we know more about this? The COVID-19 vaccine trials have as their primary endpoint illness with COVID-19. But the trials are also collecting secondary endpoints which will help understand whether they block infection. This includes collecting swabs to look for evidence of virus in the upper respiratory tract, and also testing for evidence of antibodies to other part of the virus not targeted by the vaccine. If we see these antibodies even in vaccinated people, it would suggest they were infected but just didn’t get sick. This will take some time, although it is underway.

In the meantime, basically, we need to assume that vaccinated people can still spread the virus in the same way that other asymptomatic infections would. That is to say, much less than symptomatic infections but not zero.

Is Vaccine Immunity the Same As Having-Had-COVID Immunity?

The technology through which the mRNA vaccine works in your body is basically exactly how your body generates natural immunity (seriously, go listen to the Bio Eats World podcast). There is one difference. When you are infected with the actual COVID-19 virus your body produces antibodies that target multiple parts of the virus, not just the spike protein (although the spike protein is often a primary target). The vaccine targets only the spike protein.

The vaccine generates a really robust antibody response to the spike protein which could actually be more effective than natural immunity, which is why generally even people who have had COVID-19 are recommended to get the vaccine. “Natural” immunity may be more protective against large mutations in the spike protein, but (a) this isn’t obvious since natural immunity also often targets the spike protein and (b) it requires you to get COVID-19 which is not good.

However: from the standpoint of these behavior questions, it is broadly reasonable to think of both naturally acquired immunity and vaccine-acquired immunity as the same. That is: the possible risk of spreading the virus to others remains, but you are yourself highly protected from getting sick (or, sick again in the case of natural immunity).

Importantly, it is possible that immunity wanes over time and this is true for both naturally and vaccine acquired immunity and we do not yet know the time frame.

Back to the Questions

So let’s get back to the questions. I’ll try to bucket them a bit.

One adult is vaccinated in the household. They should still be careful outside of the household to avoid infecting other people at home.

Elderly relative is vaccinated, can we see them? This is more complicated. In a lot of cases (like the 90 year old question above) the primary (not only, but primary) reason not to see them was to avoid getting them sick. We do not want anyone to get COVID-19, but the risks are much, much greater to the elderly. And there are clear benefits to seeing each other. So I would say that at a minimum the vaccination changes the calculus a lot here. You cannot completely rule out that the older person will infect others, but it is also a lesser concern. Especially given the fact that they will not have symptomatic infection, the risks are low.

It’s also often the case that the older people in these examples are themselves fairly isolated and not doing a lot of risky activities. The main risky activity might be seeing their family. In which case, great. Now that risk is gone for them, you should feel much more comfortable.

Can I have an unmasked indoor party with my other vaccinated friends? What about the ones that already had COVID-19? Early on there was some discussion of how, basically, saying yes to questions like this would encourage young people to go out and get COVID-19 so they could do this. So I am reluctant to answer this. But the answer is sort of yes or, at least, that such a party would not lead to you all getting sick.

HOWEVER: see all discussion above. If you get infected at the party, even if you do not get sick, you could bring it back to your family. So unless you’re literally living in a bubble where everyone is vaccinated the most careful thing is to not having any indoor unmasked parties for now.

THIS MAKES IT SOUND LIKE IT WILL NEVER END AND I AM UNSUBSCRIBING RIGHT NOW

I also felt like this writing this. Like, if our kids aren’t vaccinated until the fall can we never do anything? Argh.

BUT: I don’t think it is as bad as all that. For one thing, asymptomatic cases seem to spread much, much less. This means that as more and more people are vaccinated, we’re likely to be able to let down our guard a bit. If we learn there is sterilizing immunity from the vaccine, then that will change things even more.

In addition, when we think about kids, the risks to them are very, very low. If everyone else is vaccinated, we should be able to start to return to normal life even as we wait for children.

Also very important: one of the huge issues we are facing right now that a lot of people are sick. We are running out of hospital beds. People are not getting care for what they need. As we vaccinate people this will improve. Because they will not get sick. This will help us return to normalcy.

So, please cancel your vaccine celebration parties for now, but possibly it’s okay to see your elderly isolated relatives after they are vaccinated. And try to breathe.

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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
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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
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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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