One-third of children with COVID-19 are asymptomatic
Click Here to Manage Email Alerts
About one-third of children who tested positive for SARS-CoV-2 were asymptomatic, an observational study in Canada showed.
Researchers cautioned that although cough and rhinorrhea were two of the most common symptoms among children who were infected, these symptoms were also commonly reported among approximately 500 children with negative test results and “were not predictive” of a positive SARS-CoV-2 test.
“Identifying children who are likely to be infected is challenging,” James A. King, MSc, an analysist with Provincial Research Data Services in Canada, and colleagues wrote.
The researchers reviewed data from 2,463 children who were tested for SARS-CoV-2 infection via swab or another test between April 13 and Sept. 30, 2020.
Results, published in the CMAJ, indicated that 1,987 of the children tested positive for SARS-CoV-2 infection (mean age, 9.3 years) and of these, 35.9% were asymptomatic. Cough and rhinorrhea were two of the most common symptoms among the children with positive test results (24.5% and 19.3%, respectively), but these symptoms were also common among the children with negative test results (mean age, 8.5 years) and thus, not predictive of a positive test (positive likelihood ratio [LR] = 0.96; 95% CI, 0.81-1.14, and positive LR = 0.87; 95% CI, 0.72-1.06, respectively).
“We can do all the COVID-19 questionnaires we want, but if one-third of the kids are asymptomatic, the answer is going to be no to all the questions — yet they're still infected,” Finlay McAlister, MD, MSc, a professor of medicine at the University of Alberta in Canada, said in a press release.
According to the researchers, anosmia/ageusia (positive LR = 7.33; 95% CI, 3.03-17.76), nausea/vomiting (positive LR = 5.51; 95% CI, 1.74-17.43), headache (positive LR = 2.49; 95% CI, 1.74-3.57) and fever (positive LR = 1.68; 95% CI, 1.34-2.11) were the symptoms most predictive of a positive SARS-CoV-2 test among children. The positive LR for the combination of anosmia/ageusia, nausea/vomiting and headache was 65.92 (95% CI, 49.48-91.92).
King and colleagues noted that many of the symptoms identified in children who tested positive closely align with those in adults. However, “it is worth highlighting that most symptoms associated with SARS-CoV-2 positivity were uncommon in children and would therefore have poor sensitivity in a potential screening test.”
In a related editorial, Nisha Thampi, MD, MSc, FRCPC, an assistant professor and pediatric infectious diseases consultant with the Children’s Hospital of Eastern Ontario, and colleagues wrote that King and colleagues’ findings underscore the critical role that hand hygiene, improved ventilation, masking, outdoor learning and physical distancing play in preventing the spread of infection among school-aged children.
References:
King JA, et al. CMAJ. 2020;doi:10.1503/cmaj.20206.
Thampi N, et al. CMAJ. 2020.doi:10.1503/cmaj.202568.