Researchers Propose Looking for 'Silent' COVID Infections in 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."

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. 

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.