From a frequency of symptoms perspective, fever, cough or shortness of breath occur in about 6 out of ten children 0-19 years of age. Point of care testing needed to help parents and schools avoid misdiagnosis when a child has the sniffles.

Medical Mythbusting Commentary for September 30, 2020

Source:
These coronavirus symptoms are more concerning for kids than the sniffles: B.C. doctor

Reference:

From UpToDate.com (last updated September 14, 2020)

In children of all ages — The symptoms of COVID-19 are similar in children and adults, but the frequency of symptoms varies. COVID-19 appears to be milder in children than in adults and their symptoms may be unrecognized before diagnosis, but severe cases have been reported.

Among 69,703 laboratory-confirmed cases of COVID-19 in children <20 years reported to the United States Centers for Disease Control and Prevention (CDC) by May 30, 2020, boys and girls were equally affected. In a systematic review of observational studies including 7480 children with laboratory-confirmed COVID-19, predominantly from Italy, China, and the United States, the weighted mean age was 7.6 years.

Although the clinical findings in children with COVID-19 are diverse, fever and cough are the most common reported symptoms. In case surveillance in the United States (through May 30, 2020), information about symptoms was available for 5188 children age 0 through 9 years and 12,689 children age 10 through 19 years.

Among children age 0 through 9 years, the frequency of symptoms was as follows:

●Fever, cough, or shortness of breath – 63 percent

•Fever – 46 percent

•Cough – 37 percent

•Shortness of breath – 7 percent

●Myalgia – 10 percent

●Rhinorrhea – 7 percent

●Sore throat – 13 percent

●Headache – 15 percent

●Nausea/vomiting – 10 percent

●Abdominal pain – 7 percent

●Diarrhea – 14 percent

●Loss of smell or taste – 1 percent

Among children age 10 through 19 years, the frequency of symptoms was as follows:

●Fever, cough, or shortness of breath – 60 percent

•Fever – 35 percent

•Cough – 41 percent

•Shortness of breath – 16 percent

●Myalgia – 30 percent

●Rhinorrhea – 8 percent

●Sore throat – 29 percent

●Headache – 42 percent

●Nausea/vomiting – 10 percent

●Abdominal pain – 8 percent

●Diarrhea – 14 percent

●Loss of smell or taste – 10 percent