Comparison of clinical characteristics and severity of COVID-19 with or without viral co-infection in hospitalized children.

Background: Co-infection with other pathogens can alter the severity and clinical outcomes of viral infections. However, the information regarding viral co-infections in pediatric coronavirus disease 2019 (COVID-19) cases is still limited.
Methods: This is a nationwide, retrospective cohort study using the data from the COVID-19 Registry Japan. The pediatric (<18 years), laboratory confirmed, hospitalized COVID-19 patients in the Omicron variant of concern predominant period (January 2022 to January 2024) were included. Co-infection was investigated by multiplex PCR. We compared clinical characteristics, symptoms, severity, and outcomes between children with and without co-infection.
Results: Among 245 hospitalized pediatric COVID-19 patients, 78 (31.8 %) had co-infections. The patient backgrounds of the "co-infection" and "SARS-CoV-2 alone" groups were similar, although age distribution was different, with a lower number of patients over 12 years in the co-infection group (n = 2, 2.6 % vs. n = 29, 17.4 %; P < 0.001). Among the patients with co-infection, the most common pathogen was enterovirus/rhinovirus (51.3 %), followed by parainfluenza virus (23.1 %) and adenovirus (12.8 %). Patients with co-infection more commonly had respiratory symptoms, including SpO ₂ < 96 %, shortness of breath, runny nose, and wheezing. Requirement of non-invasive oxygen support was higher in the co-infection group (n = 27, 34.6 % vs. n = 28, 16.8 %, P = 0.006). By multivariable logistic regression analysis, co-infection and presence of any comorbidity were identified as significant risk factors for necessity of oxygen therapy (odds ratio [95 % confidence interval] 2.44 [1.29-4.63] and 3.99 [2.07-7.82], respectively).
Conclusions: Viral co-infection may increase the risk of respiratory distress in pediatric COVID-19 patients.
Competing Interests: Declaration of competing interest K. Shoji received payment for lectures from bioMérieux Japan, Nippon Becton Dickinson Company, Ltd., Viatris, Inc., Meiji Seika Pharma Co., Ltd., AstraZeneca K.K., Novartis Pharma Co., Ltd., Kyorin Pharmaceutical Co., Ltd., and Gilead Sciences, Inc. S. Tsuzuki received payment for supervising medical articles from Gilead Sciences, Inc. I. Miyairi received payment for lectures from Astellas Pharma, Sanofi K.K., Pfizer, Inc., Takeda Pharmaceutical Company, Ltd., Biken Group, Shionogi & Company, Ltd., bioMérieux Japan, Gilead Sciences, Inc., Meiji Seika Pharma, KM Biologics, Tanabe-Mitsubishi Pharmaceuticals, and Daiichi Sankyo. The other authors declare that they do not have any conflicts of interest directly associated with the study.
(Copyright © 2024 Japanese Society of Chemotherapy, Japanese Association for Infectious Diseases, and Japanese Society for Infection Prevention and Control. Published by Elsevier Ltd. All rights reserved.)