SARS-CoV-2 Coinfections and Severity in Hospitalized Children With Systematic Testing
Year: 2026
Type: article
Study design: Observational Study
Abstract: BACKGROUND: Co-circulation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with other respiratory viruses raised concerns that coinfections may increase pediatric coronavirus disease 2019 (COVID-19) severity, but evidence is limited by variable testing practices. We assessed the epidemiology and outcomes of SARS-CoV-2 respiratory viral coinfections in hospitalized children. METHODS: We analyzed national surveillance data from the Canadian Immunization Monitoring Program, ACTive (IMPACT) COVID-19 study. Children aged <17 years hospitalized with confirmed COVID-19 during Delta and Omicron periods were included. Coinfection was defined as SARS-CoV-2 plus ≥1 additional respiratory virus. Primary analyses were restricted to centres with systematic multiplex polymerase chain reaction (PCR) testing of all admissions with acute respiratory illness (n = 5), while secondary analyses included all centres (n = 13). Associations with outcomes (respiratory support, ventilation, intensive care and severe COVID-19) were estimated using multivariable mixed-effects logistic regression and adjusted odds ratios (aORs). RESULTS: Among 2831 hospitalized children, 938 were admitted at centers with systematic multiplex PCR testing, among whom 18.6% had ≥1 respiratory viral coinfection. Respiratory syncytial virus (39.7%) and enterovirus/rhinovirus (38.5%) coinfections were the most common. Coinfections were not associated with increased odds of severe COVID-19 in centers with systematic multiplex PCR testing (aOR 0.94; 95% confidence interval, 0.76-1.15). In secondary analyses including all centers irrespective of testing strategy, coinfections were associated with increased odds of severe COVID-19 (aOR 1.42; 95% confidence interval, 1.05-1.91). CONCLUSIONS: In centers that systematically conducted multiplex PCR testing, SARS-CoV-2 respiratory viral coinfections were not associated with increased COVID-19 severity. Differences observed when including centers without systematic testing underscore the importance of considering testing strategies when evaluating the clinical impact of coinfections.
Authors: Costanza Di Chiara, Daniel S. Farrar, Julie A Bettinger, Aaron Campigotto, Olivier Drouin, Joanne Embree, Scott A. Halperin, Taj Jadavji, Kescha Kazmi, Jesse Papenburg, Rupeena Purewal, Manish Sadarangani, Laura Sauvé, Karina A. Top, Fatima Kakkar, Shaun K. Morris, for Members of the Canadian Immunization Monitoring Program, Active (IMPACT) COVID-19 Study
Institutions: Hospital for Sick Children, University of British Columbia, BC Children's Hospital Research Institute, Centre Hospitalier Universitaire Sainte-Justine, Université de Montréal, University of Manitoba, Dalhousie University, Izaak Walton Killam Health Centre, Canadian Centre for Vaccinology, Alberta Children's Hospital, Montreal Children's Hospital, McGill University Health Centre, McGill University, University of Alberta, University of Toronto
Language: English
Subfield: Infectious Diseases
Field: Medicine
Domain: Health Sciences
Open Access status: hybrid
Funder: Public Health Agency of Canada
OpenAlex ID: W7212129678