
When I got a breakthrough COVID infection in December at the height of the omicron surge in New York City, I was certain I’d pass it on to my two young kids. One is old enough to be vaccinated; the other isn’t. We live in a small two-bedroom apartment and were stuck together for 10 days.
Surprisingly, neither of my kids tested positive. That could have to do with the fact that household transmission is not a given. Recent Centers for Disease Control estimates suggest that during the omicron wave, 1 in 2 household contacts developed COVID-19 — a high risk of infection, but not inevitable.
But it also seems possible that my kids didn’t get sick because they’d already built up immunity through prior infection that my husband and I just didn’t know about.
I’m especially skeptical that my 3-year-old has truly gotten through the past two years unscathed. He was home with us for a long stretch early in the pandemic but has ultimately returned to day care, and then preschool, where his masking has been, at best, unenthusiastic.
So what are the odds that my kids — or your own — had COVID at some point in the pandemic and you just didn’t know? Here’s what the most recent research says.
New data suggests asymptomatic spread has been really widespread — especially among kids.
The CDC recently released new estimates that suggest that, as of late January this year, about 140,000,000 Americans have been infected with COVID-19. That’s roughly 43% of the U.S. population.
That estimate comes from more than 70,000 blood samples tested in January specifically for antibodies generated after COVID-19 infection. Known as a seroprevalence survey, this research estimates the percentage of people in a population who have antibodies to something infectious — in this case, SARS-CoV-2, the virus that causes COVID-19.
Notably, the 140,000,000 estimate the CDC found is about double what verified case counts suggest, which means millions of people in this country have had COVID without knowing it.
And the infection rate among kids seems to be even higher. The recent CDC data found that 58% of kids up to age 17 have COVID antibodies.
It makes sense. Children were in school during the omicron wave, and that variant is much more contagious than previous ones. Kids also tend to have milder symptoms than adults, so their parents and caregivers simply may not have known they were infected at all.
There’s no way for most parents to reliably test whether their child was infected.
While using antibody tests to get a broad, population-level estimate of how many people have had COVID can be a valuable public health tool, it’s not as useful individually.
“[Antibody testing] is primarily done by blood draw, but several kits are available to do by finger stick as well,” Dr. Kelly Fradin, a pediatrician and author of “Parenting in a Pandemic,” told HuffPost. The CDC advises that people reach out to their doctor to ask about whether they need one.
“Notably, if your child had COVID months ago, or had a mild case of COVID, the antibodies generated might have come and gone before you do the test. Accordingly, a test is limited in its ability to tell you about prior infection.”
And that is one reason why seroprevalence surveys can really only offer estimates, not exact numbers of how many people have had COVID during a certain period of time.
Of course, there are different considerations for children who are immunocompromised or who have underlying health conditions. In those instances, health care providers may pay very close attention to signs of possible COVID infection in addition to tracking antibody levels after vaccination.
We still don’t know how long “natural” immunity lasts.
Not only can antibody tests miss prior infections depending on how much time has lapsed, but there are also bigger questions about how long someone is immune to COVID after they are infected with it.
Most experts believe you (or your child) are protected from COVID for at least three months — possibly up to six — after an infection, but that’s really a best guess. And recent data from the Netherlands suggests that some people who were infected with the initial omicron variant, BA.1, have been getting infected with the newer omicron variant, BA.2, less than two months after their initial infection.
Fradin noted that at some point down the road, as we learn more about COVID’s long-term impact on things like heart health, experts might want to know if kids have been infected so they can, say, screen them before they participate in sports. But that’s just a hypothetical scenario at this point.
For now, given the limitations of antibody testing — as well as the fact that no one really knows how much a COVID infection protects kids after they catch the virus — it may not matter much whether my kids have had COVID up to this point.
If you wonder how to make certain decisions about your child’s activities over the next few months as omicron continues to recede and mask mandates and other restrictions disappear, talk to your child’s pediatrician. They may not be able to tell you definitively whether your kiddo has had COVID before, but they can help you figure out how to move forward in a way that feels right for your family.
Experts are still learning about COVID-19. The information in this story is what was known or available as of publication, but guidance can change as scientists discover more about the virus. Please check the Centers for Disease Control and Prevention for the most updated recommendations.