SAN DIEGO (KGTV) — The Centers for Disease Control and Prevention is releasing its first study on the impact of COVID-19 on children in the United States.
The results are similar to the impact of the virus on children in China.
Dr. Mark Sawyer is a pediatric infectious disease specialist at Rady Children's Hospital and the program director of the Pediatrics Residency Program at the UC San Diego School of Medicine.
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"It's actually really good news, the vast majority of children who get infected with COVID have very minor, or in some cases, no symptoms at all. If you look at all the cases of COVID in the United States only between 1 and 2 percent, actually I think in this study it was 1.7 percent are in children 18 years of age and younger. There are a few kids who got severely ill with this, but that has been very, very infrequent," said Sawyer.
The CDC study finds 73 percent of pediatric patients had fever, cough, and shortness of breath, compared with 93 percent of adults. Roughly, 6 percent required hospitalization compared with 33 percent of adults. Children under the age of 1 had the highest percentage of hospitalizations.
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Sawyer says one theory is that children are less affected by the virus because their immune systems are not as robust as adults.
"There is some evidence now in adults, the reason they get so sick is they have an overreaction of their immune system, and they may be set up for that having been infected in the past with other different coronaviruses that there is some cross reaction," says Sawyer, adding that the overreaction may lead to severe illness.
"Their immune system sort of goes crazy and sets off a cascade of events that leads to the severe illness," Sawyer said.
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Sawyer said another theory is that receptors on the cells of a child's respiratory tract may be less susceptible to the virus. Finally, social distancing is easier to do with a child.
"I think people can be reassured that their children are unlikely to get severe illness with this. I think the biggest concern about children is whether they are part of the problem spreading the virus around to family members, including adults, and grandparents," said Sawyer.
So far, Rady Children's Hospital has admitted two patients with COVID-19, but both had mild symptoms.