CHICAGO (WLS) -- While a very small number of kids have become sick from COVID-19 related illnesses, most children continue to be symptom free. Pediatric infectious disease experts are beginning to offer some explanations as to why kids are not getting sick with the coronavirus.
"One of them has to do with kids' immune response is different than adults'," said Dr. Daniel Johnson, Comer Children's Hospital Infectious Disease Specialist. "Part of it is they are exposed to different viruses, so maybe they have some degree of immunity."
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Johnson said kids also have a different distribution of immune-based cells that may lead to a different response. He also said a lot of the response to COVID-19 is being driven by conditions that compromise the immune system.
"Adults tend to be heavier, they have heart disease, diabetes, hypertension, things that kids thankfully have in way lower incidences," Johnson said.
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But children are spreading the disease, Johnson said, though unlike the flu only 10 percent of children are the source of the virus. Still, it's enough that doctors say children aged 2 and older must wear masks.
Doctors are also urging teenagers to be more cautious. Pediatricians say teens are having trouble getting the message about wearing masks and social distancing.
Coronavirus: Pediatricians probe why children are much less affected by COVID-19