Vaccinated Kids Show No Long-Term Ill Effects

No measurable increase in risk for neurological conditions could be found in a large cohort of pre-adolescent children who had been vaccinated on schedule when infants. Wayt Gibbs reports

Join Our Community of Science Lovers!

As any new parent knows, vaccines are a pain in the tuchus—and not just for the infant. A baby born in the U.S. today is supposed to get 20 shots by the age of two. Unsurprisingly, many parents put it off. What is surprising is why: in a 2011 survey by the Centers for Disease Control and Prevention, 82% of parents who didn’t vaccinate their children on schedule cited worries about side effects, like learning or behavioral problems.

So the CDC commissioned a big study to look at this question. Researchers gathered vaccination records and ran a wide range of tests on more than a thousand 7- to 10-year-olds. The scientists then searched for any sign that fully vaccinated kids had an elevated risk of cognitive deficits, tics, speech impediments, learning disability or issues with attention or executive function.

The results were clear: there was no measurable increase in risk for any of these conditions among children who got vaccinated on schedule. The study is in the journal Pharmacoepidemiology and Drug Safety. [Shahed Iqbal et al, Number of antigens in early childhood vaccines and neuropsychological outcomes at age 7–10 years]


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


This good news should ease some of the anxiety from those visits to the pediatrician—unless, of course, you’re the one getting stuck.

—Wayt Gibbs

[The above text is a transcript of this podcast.] 

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American

Subscribe