Researchers observed 91 children younger than 19 years old with COVID-19 from February 18 to March 31 in 20 hospitals and 2 non-hospital isolation facilities across the Republic of Korea.
About 22 percent of them were asymptomatic. Only 8.5 percent of symptomatic cases were diagnosed at the time of symptom onset, while 66.2 percent had unrecognized symptoms before diagnosis and 25.4 percent developed symptoms after diagnosis, according to the study.
SARS-CoV-2 RNA was detected for a mean of 17.6 days overall and 14.1 days in asymptomatic cases, said the study.
The results show symptom screening fails to identify most COVID-19 cases in children, and SARS-CoV-2 RNA in children is detected for an unexpectedly long time, according to the study.
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