Researchers Propose Looking for 'Silent' COVID Infections in Kids

covid-19 testing
Broadly testing children may help prevent the spread of COVID-19.

Key Takeaways

  • "Silent" COVID-19 infections—when a person is positive for the virus but does not have symptoms—have been a driving force in the pandemic that has been hard to curb.
  • A modeling study found that detecting these infections early—particularly in kids—could help lower cases in the general population.
  • While identifying "silent" COVID infections could help, doctors stress that vaccination is still important. While adults can get vaccinated now, clinical trials are still underway to approve a COVID vaccine for kids.

"Silent” COVID-19 infections—when a person tests positive for the virus but does not have any symptoms—have been a major concern for public health experts during the pandemic. A new study suggests that identifying even a small percentage of "silent" COVID-19 infections in children could dramatically lower case rates in the general public if adults are vaccinated.

Research has shown that around one-fifth of people infected with COVID-19 may have silent infections. Despite having no symptoms, previous studies have found that people with silent COVID-19 have as much of the SARS-CoV-2 virus in their systems as people who have signs of the illness.

People are generally considered to have a silent COVID-19 infection if they test positive for the virus without having any of the following symptoms:

  • Fever
  • Chills
  • Muscle pain
  • Fatigue
  • Runny nose/congestion
  • Loss of taste and/or smell
  • Sore throat
  • Swallowing difficulties
  • Cough
  • Phlegm production or coughing up blood
  • Headache
  • Dizziness
  • Loss of appetite
  • Nausea
  • Vomiting
  • Abdominal pain
  • Diarrhea

Danelle Fisher, MD, FAAP, a pediatrician and the chair of pediatrics at Providence Saint John’s Health Center in Santa Monica, California, tells Verywell that these silent COVID infections can be dangerous, “because they can spread to everybody. If children don’t know that they have COVID, the parents and grandparents can get it—and that’s how we get more community spread.”

What the Study Found

The study, which was published in the journal JAMA Network Open, used simulation modeling to see how COVID-19 rates would change if children were broadly tested for COVID-19 compared to only vaccination efforts.

The researchers found that if only adults were vaccinated, identifying 10% to 20% of silent COVID cases in children (within three days of infection) would bring new case rates below 5%.

By contrast, if the silent infections in children go undetected, keeping case rates down would require what the researchers called an “unrealistically high” vaccination rate of more than 81% of children, in addition to vaccinating adults.

In conclusion, the researchers wrote that their findings "suggest that rapid identification of silent infections among children may achieve comparable effects as would their vaccination."

Vaccination Still Matters

The idea of broadly testing school-age children seems like a lot, but Fisher points out that it’s already happening in some school districts across the country. She says that her son is "getting tested every week at school. We’re already doing this in some areas.”

Fisher says that the potential problem now is that summer is coming—a time when children will be out of school and won’t be getting tested regularly. While Fisher hopes that there will be high uptake of COVID vaccination in kids once it becomes available, she thinks that uptake "will mirror what we see in the general population" and that "those who refuse it for themselves will similarly refuse it for their children."

A Pew Research poll published in March revealed that about 30% of Americans do not plan to get vaccinated against COVID-19.

According to data from the Centers for Disease Control and Prevention (CDC), almost one-third of Americans are currently fully vaccinated against COVID. More than 44% of Americans have gotten at least one dose.

Richard Watkins, MD, an infectious disease physician and a professor of internal medicine at Northeast Ohio Medical University, tells Verywell that vaccination is still crucial to protect the public—and that includes children. “Some kids who get COVID can get really sick and, rarely, can die," says Watkins. "No parent wants that to happen to their child.”

Watkins says that vaccination “needs to be strongly encouraged” when it’s available for younger children. Currently, clinical trials are testing the COVID-19 vaccines in children as young as six months. It’s unclear when they will be available to younger children, but some estimates say it could happen by the end of 2021. 

What This Means For You

Until the COVID-19 vaccine is available to children under the age of 16, broad testing in schools may help prevent the spread of the virus. However, it would not replace the importance of vaccine efforts or practicing preventive strategies like masking, social distancing, and frequent handwashing.

The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit our coronavirus news page.

3 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Moghadas SM, Fitzpatrick MC, Shoukat A, Zhang K, Galvani AP. Simulated identification of silent COVID-19 infections among children and estimated future infection rates with vaccinationJAMA Netw Open. 2021 Apr 1;4(4):e217097. doi:10.1001/jamanetworkopen.2021.7097

  2. Ra SH, Lim JS, Kim G, Kim MJ, Jung J, Kim S-H. Upper respiratory viral load in asymptomatic individuals and mildly symptomatic patients with SARS-CoV-2 infectionThorax. 2021;76(1):61-63. doi:10.1136/thoraxjnl-2020-215042

  3. Centers for Disease Control and Prevention (CDC). COVID vaccinations in the United States.

By Korin Miller
Korin Miller is a health and lifestyle journalist who has been published in The Washington Post, Prevention, SELF, Women's Health, The Bump, and Yahoo, among other outlets.