Children under the age of 5 can carry as much coronavirus in their nose as older children and adults, researchers at Lurie Children’s Hospital in Chicago said on Thursday.
A study published in the journal JAMA Pediatrics raises the possibility that young children may spread COVID-19 as easily as adults, even if they are not.
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Tauror Heald-Sargent, a pediatric infectious disease specialist at Lurie Children, and her colleagues analyzed diagnostic data from 145 COVID-19 patients with mild to moderate disease. The tests look for pieces of the virus̵7;s RNA or genetic code to make a diagnosis.
145 patients were divided into three groups: those under 5, 5–17 years, and adults 18–65 years.
“Children had equal, if not more, viral RNA in their noses compared to older children and adults,” said Heald-Sargent.
Compared to adults, young children had 10 to 100 times more viral RNA in the upper respiratory tract, the study’s authors wrote.
“This supports the idea that children can become infected and multiply the virus, so they spread and transmit the virus as much as older children and adults,” she said, noting that more research is needed to confirm this.
In fact, “you can have someone whose nasal viruses are very large, but that doesn’t mean they will spread more than someone with a little less,” Dr. Rick Malley, a senior pediatrician in the division of infectious diseases at Boston Children’s Hospital.
“We don’t really know that,” said Malley, who is not involved in the new investigation.
The findings, however, add another question to the difficult question of whether schools should open their doors again for the fall semester, and if so, how to do so safely?
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“We have no evidence that children will play the same role with this virus as, say, the flu virus, when it is quite clear that children with influenza are major drivers of the spread,” Malley said.
However, he added, COVID-19 “behaves unpredictably”.
Some young people have developed a potentially fatal disease called multifunctional inflammatory syndrome in children, or MIS-C, which is thought to be linked to COVID-19.
The condition is quite rare; The Centers for Disease Control and Prevention reported that on 15 July. 342 cases of MIS-C were diagnosed in the country. Six children died.
However, children were generally rescued from the worst effects of COVID-19.
In the Heald-Sargent study, patients ranged in age from less than 1 month to 65 years. Those who needed breathing assistance were not included. All were diagnosed in March and April.
Lurie Children required all hospitalized patients to take the COVID-19 test, and some cases were identified even if the children had no symptoms or no symptoms at all.
“We were catching kids who came in with a broken arm who were randomly positive,” Heald-Sargent said.
The prevalence of COVID-19 in children remains unclear, in part because studies are limited, especially in those without symptoms. Schools have been closed since the spring, making it difficult to determine how children can spread the virus.
There are several theories as to why children may not spread coronavirus as easily as adults: Their lung capacity is smaller, so they may not be able to cough or sneeze with the same force as adults. Also, any drops of breath they emit can fall to the floor because their bodies are just closer to the floor.
Heald-Sargent, raising her young children, rejected the latter idea. “We have to remember that COVID-19 can be excreted in the feces, it can be in the mouth and nose. Children touch it. They are little germ factories.”
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