Emily Oster

3 min Read Emily Oster

Emily Oster

Should I Make My Relatives Get a Tdap Booster?

Q&A on visiting a newborn

Emily Oster

3 min Read

I am 35 weeks pregnant, and my husband and I live across the country from our families, who plan to fly out in the early days and months after the baby is born. We have one family member who is resistant to getting a Tdap booster, as is recommended for those who will be around or caring for the baby. Can you speak to the data on the importance of the Tdap vaccine, to help us make an informed decision about what we’re comfortable with if this person does not get a Tdap booster (assuming they haven’t had one in the past 10 years)? Some things I’d love to clarify are whether that person wearing a mask would offer comparable protection and just how risky it would be to allow them to be around the baby if unvaccinated.

—Torn about Tdap

The Tdap vaccine protects against a number of things (tetanus, diphtheria, and pertussis), but from the standpoint of infants, pertussis is the relevant issue. Also known as whooping cough, this is a virus that can cause serious illness or death in very young infants, especially those who are premature. 

Close up of older person's hand holding child's hand
Getty

Pertussis is typically rare, due to widespread vaccination. The CDC estimated 5,611 cases in 2023 although that is likely an undercount given that many cases are not reported. Of these, 376 cases were in babies under six months. These infants had a 21% chance of hospitalization; 376 babies out of 3.5 million births is a small number, but the hospitalization rate is high. It is worth noting that 2024 has been worse for pertussis, likely due to a reduction in childhood vaccines. 

What to do to prevent illness? First, your baby will start Tdap doses at two months of age (those are part of the first set of shots), which will give them some protection. In addition, maternal vaccination during pregnancy has been shown to be about 90% protective against Tdap in infants under two months. This choice — to get vaccinated yourself during pregnancy — is the most important protection you can give your baby. 

What you are asking about is sometimes called “cocooning”: having all individuals who are going to be in contact with the infant get a Tdap booster. This is a long-standing recommendation, but the evidence is poor. Tdap vaccination doesn’t prevent people from transmitting the virus (although it may make it less likely), so it is not obvious that it matters. ACIP, the CDC’s Advisory Committee on Immunization Practices, says in its 2018 evidence summary that the evidence for this practice is weak. The committee underscores that the most important preventive measure is maternal vaccination. There is really no evidence that requiring everyone to be vaccinated will have any impact at all.

My read of this is that you should not restrict baby access for the person without the vaccine (assuming you want to see them!). Masking isn’t necessary; having visitors wash their hands when they arrive and making sure people are not actively sick (with anything) is strongly recommended.

Community Guidelines
0 Comments
Inline Feedbacks
View all comments
A toddler is seen sitting on the lap of a parent. The child is blowing their nose into a tissue held by the parent.

Dec. 16, 2021

9 min Read

What Things Can I Do with My Baby?

Germ exposure and preserving sanity

a parent is standing holding the newborn and a grandparent is trying to help

Oct. 14, 2022

4 min Read

When Should I Allow Visitors Around My Newborn?

My due date is December. 4, and we already have out-of-town relatives requesting to fly in for Christmas who are Read more

A doctor placed a bandaid on the arm of a pregnant person after administering a vaccination.

May. 30, 2023

8 min Read

RSV and Vaccines

Respiratory syncytial virus, or RSV, is a common respiratory virus. Unless you are very, very unusual, by the time you’re Read more

Smiling young child flexes and shows of a bandaid from a recent vaccination.

Sep. 25, 2023

13 min Read

Your Guide to Vaccines During Pregnancy and Early Childhood

There was a time — let’s say, 2019 — when people did not talk as much about vaccines. It’s not Read more