Children face similar risk of coronavirus infection as adults, new study suggests

Children are almost as likely as adults to become infected with coronavirus, but they are less likely to have symptoms, according to a new study published Friday.

The new study, published in the journal JAMA Pediatrics, found adults and children living in Utah and New York City shared similar risks of becoming infected with coronavirus. But kids only had symptoms about half the time.

"The study demonstrates that all along, children of all ages including infants and toddlers have had a similar risk of SARS- CoV-2 infection compared with adults," Dr. Flor Munoz, a pediatric infectious disease specialist at Texas Children's Hospital and associate professor of pediatrics at Baylor College of Medicine, wrote in an accompanying editorial. SARS-CoV-2 is the name of the coronavirus that causes COVID-19.

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"The fact that children, and especially young children, can transmit SARS-CoV-2 is now established and more clearly understood," wrote Munoz, who was not involved in the study. She added that the new findings should be considered in pandemic control efforts as well as vaccine and therapeutics research.

These findings were published just a day after the companies Pfizer and BioNTech officially requested emergency use authorization from the U.S. Food and Drug Administration for their COVID-19 vaccine, at a smaller dosage, in children ages 5 to 11.

The new research, conducted from September 2020 through April 2021, included data on 1,236 people from 310 different households with one or more children in New York City, and certain counties throughout Utah.

Dr. Fatimah Dawood of the US Centers for Disease Control and Prevention and colleagues took a close look at the incidence of COVID-19 and found that among households with one or more people infected, the mean infection risk within those households was 52%, adding to the evidence that households remain a common place that the virus spreads.

When they analyzed COVID-19 incidence by age group, rates per 1,000 person-weeks appeared to be similar across the board: 6.3 for children up to 4 years old; 4.4 for children ages 5 to 11; 6.0 for children 12 to 17; and 5.1 for adults.

In general, "our findings suggest that children and adults have similar incidence rates of SARS-CoV-2 infection, underscoring the need for rapid evaluation of vaccine efficacy and safety in children to expand vaccine indications to younger age groups," they wrote.

When the researchers analyzed how many people in each age group experienced no symptoms, they found asymptomatic infection among 52% of kids younger than 4; 50% of those ages 5 to 11; 45% of those 12 to 17; but in just 12% of adults.

"Adults and children of all ages had similar risks of SARS-CoV-2 infection, but approximately half of SARS-CoV-2 infections among children were asymptomatic compared with a much smaller fraction among adults," the researchers wrote.

The researchers noted that some symptoms among young children might have been missed since the data on symptoms were collected from the adult caregivers of the kids -- not the kids themselves.

Overall, the role children play in transmitting respiratory infections should be considered in pandemic control efforts as well as the need for a COVID-19 vaccine for children, Munoz wrote in her editorial.

"If lessons are to be learned from our collective experience and if we agree to acknowledge the role of children in the transmission of respiratory viral infections, then pediatric populations, from infants to adolescents, must be included in pandemic preparedness, disease burden assessment, timely vaccine and therapeutics research, and strategies and policies for the control of outbreaks and pandemics from day 1 without delay," she wrote.