Children under 5 can carry large coronoviruses in their noses as older children and adults, researchers at Chicago’s Lurie Children’s Hospital reported on Thursday.
The study, published in the journal JAMA Pediatrics, raises the possibility that young children may be able to spread COVID-19 as easily as adults, even if they are not that sick.
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Dr. Taylor Heald-Sergeant, a pediatric infectious disease specialist at Lurie Children’s, and his colleagues analyzed data from clinical trials of 145 COVID-19 patients who had mild to moderate cases of the disease. Tests seek out RNA or genetic code fragments of the virus to make a diagnosis.
The 145 patients were divided into three groups: they were less than 5 years old, 5 to 17 years old, and adults were 18 to 65 years old.
“Children were similar – if not more – to viral RNA in their noses than older children and adults,” said Heald-Sargeant.
The study authors wrote that young children have 10 to 100 times the amount of viral RNA in their upper respiratory tract than adults.
“This supports the idea that children are capable of being infected and replicating the virus and therefore shedding and transmitting the virus only to as many older children and adults as possible,” she said, more to confirm this Research is required.
Indeed, “You may have someone who has a high viral load in their nose, but that doesn’t mean they’re going to spread more than someone who has less,” senior physician Dr. Rick Malle said pediatrics in the infectious diseases division at Boston Children’s Hospital.
“We don’t know that for sure,” said Malle, who is not involved with the new study.
Nevertheless, the findings add another layer to the complex question of whether schools should reopen their doors for the fall semester, and if so, how to do so safely.
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“We do not have evidence that children will play the same role with this virus as they do, say, with the flu virus, where it is very clear that children with flu are the main drivers of the spread.” Mailey said.
However, he said, COVID-19 is “behaving in an unexpected way.”
Some youth have developed a potentially fatal condition called multisystem inflammatory syndrome in children, or MIS-C, which is believed to be associated with COVID-19.
The condition is relatively rare; The Centers for Disease Control and Prevention reported that as of July 15, 342 cases of MIS-C had been diagnosed in the country. Six children died.
Overall, however, children are largely spared the most severe consequences of COVID-19.
In the Heald-Sergeant study, patients ranged in age from less than 1 month to 65 years of age. Those who needed help with breathing were excluded from the study. All were diagnosed in March and April.
All hospitalized Lurie children underwent COVID-19 testing, and some cases were discovered, even though the children did not have any symptoms.
“We were holding children who came in with a broken hand that happened to test positive,” the Heald-Sergeant said.
It is unclear how prevalent COVID-19 is among children, as testing is limited, especially for those without symptoms. And schools have closed extensively since spring, making it difficult to figure out how children can spread the virus.
There are some theories as to why children cannot spread coronaviruses as easily as adults: their lung capacity is small, so they may not be able to cough or sneeze with the same force as adults. In addition, whatever respiratory drops come out may fall on the floor because their bodies are just close to the floor.
The Heald-Sergeant, who has young children of his own, rejected the latter idea. “We need to remember that COVID-19 can be shed in feces, it can be in the mouth and nose. Children touch it. They are small germ factories.”
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