Only about 2% of U.S. cases of COVID-19 affected children under 18 years of age, and when they are affected, the disease tends to be milder, and the findings from chest CT may look different, according to a paper published in PLOS Medicine and reported in The Scientist. 

This study “adds to the growing body of literature that is giving us some experience with what COVID-19 looks like in children, which, as we’re learning, is very different than what COVID-19 looks like in adults,” says Jennifer Schuster, MD, a pediatric infectious disease physician at Children’s Mercy Hospital in Kansas City.

In the new study, a research team documented the cases of 34 children, ages one month to 12 years, admitted between January 27 and February 23, 2020, to one of four hospitals in Hubei—the central Chinese province where Wuhan is—or Shaanxi, which is a province in northwest China. The patients, 14 boys and 20 girls, all had a confirmed SARS-CoV-2 infection.

The most common symptoms were fever (76 percent) and cough (62 percent), and vomiting and diarrhea were each present in 12 percent of subjects. These symptoms were more frequent in adults admitted to the hospital for COVID-19, the CDC reported in April: 86 percent of adult patients had a cough, 85 percent had fever or chills, nearly 27 percent had diarrhea, and about 25 percent had nausea or vomiting. Only six pediatric patients in the new study had underlying health conditions, such as asthma or a heart defect, while the CDC found that about 90 percent of adults had underlying conditions. Nearly half of the children were also infected with another respiratory pathogen, such as influenza A or B or Mycoplasma pneumoniae, which typically causes sore throat and cough in kids.

Eva Grayck, MD, a pediatric critical care physician and researcher at Children’s Hospital Colorado who was not involved in the study, says she was struck by the number of coinfections that the authors observed, which is different than what she has seen in Colorado. This high rate of coinfections could be explained by the seasons—China was in the middle of winter during this study—or perhaps it was early enough in the course of the pandemic that they hadn’t yet implemented steps to reduce the spread, she adds.

Read more from The Scientist and find the study in PLOS Medicine

Featured image: Typical features of CT images of pediatric patients with COVID-19. (A) Patchy shadows of high density in lobule were detected by initial CT images for Pt 1 on admission (on February 1, 2020), whereas no abnormal findings were detected for Pt 2 (on February 5, 2020). (B) Notable progression of lesions was detected for both Pt 1 (on February 6, 2020, day 5 after admission) and Pt 2 (on February 9, 2020, day 4 after admission). Black arrows point to patchy shadows of high density in lobules. CT, computed tomography; Pt, patient. Courtesy PLOS Medicine.