An early study
In a separate retrospective analysis described in a letter to the editor of the New England Journal of Medicine, Weiyong Liu, PhD, of Tongji Hospital of Huazhong University of Science and Technology and colleagues found that the most frequently detected pathogens in 366 children under the age of 16 years hospitalized with respiratory infections in Wuhan during Jan. 7-15, 2020, were influenza A virus (6.3% of cases) and influenza B virus (5.5% of cases), whereas COVID-19 was detected in 1.6% of cases.
The median age of the COVID-19 patients in that series was 3 years (range 1-7 years), and in contrast to the findings of Xia et al., all previously had been “completely healthy.” Common characteristics were high fever and cough in all six patients, and vomiting in four patients. Five had pneumonia as assessed by X-ray, and CTs showed typical viral pneumonia patterns.
One patient was admitted to a pediatric ICU. All patients received antiviral agents, antibiotic agents, and supportive therapies; all recovered after a median hospital stay of 7.5 days (median range, 5-13 days).
In contrast with the findings of Xia et al., the findings of Liu et al. showed COVID-19 caused moderate to severe respiratory illness in children, and that infections in children were occurring early in the epidemic.
Some perspective
In an interview regarding the findings by Xia et al., Stephen I. Pelton, MD, professor of pediatrics and epidemiology at Boston University, and director of pediatric infectious diseases at Boston Medical Center, noted the absence of fever in 40% of cases.
“This is important, as the criteria for testing by public health departments has been high fever, cough, and shortness of breath,” he said. “The absence of fever is not inconsistent with COVID-19 disease.”
Another important point regarding the findings by Xia et al. is that the highest attack rates appear to be in children under 1 year of age, he said, further noting that the finding of concurrent influenza A, influenza B, or respiratory syncytial virus underscores that “concurrent infection can occur, and the presence of another virus in diagnostic tests does not mean that COVID-19 is not causal.”
As for whether the finding of elevated procalcitonin levels in 80% of cases reflects COVID-19 disease or coinfection with bacteria, the answer is unclear. But none of the children in the study were proven to have bacterial disease, he said, adding that “this marker will need to be interpreted with caution in the setting of COVID-19 disease.”
Dr. Xia and colleagues reported having no disclosures. Dr. Liu and associates also reported having no disclosures. The study by Liu et al. was supported by the Ministry of Science and Technology of China, the National Mega Project on Major Infectious Disease Prevention, and the National Key Research and Development Program of China.
SOURCES: Xia W et al. Ped Pulmonol. 2020 Mar 5. doi: 10.1002/ppul.24718; Liu W et al. N Engl J Med. 2020 Mar 12. doi: 10.1056/NEJMc2003717.