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Emily Oster

2 minute read Emily Oster

Emily Oster

My Child’s Friend Isn’t Vaccinated. What Are the Risks?

Q&A about safety

Emily Oster

2 minute read

We have some friends who have chosen not to vaccinate their kids. We have gotten our child all of the vaccines recommended by their pediatrician. What are the risks of my kid interacting with their kid? 

—JS

The individual child risk is low, especially for an older kid. By the time a child is 4, they will have had a full complement of vaccines. These vaccines are extremely protective. The measles vaccine, for example, is 99% effective after two doses. Pertussis, chickenpox, and polio are all similar.

CDC / Unsplash

This question becomes a bit more complicated if there are younger siblings, if your child is too young to be fully vaccinated, or if there is a lot of interaction with elderly people or those who are in other ways seriously immunocompromised. In some cases, like measles, vaccination is sterilizing. This means that a vaccinated child cannot get the disease but also cannot spread it. 

Other vaccines do not work like this. Pertussis vaccination does a good job of protecting the vaccinated person, but it is still possible for them to spread the virus. This is less likely than if they were not vaccinated, but it can happen.  

This is to say: there should be added caution if there are people who surround your child who might not be as well protected. But just from the individual child standpoint, the concern is minimal. 

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