Analysis of Pathogens Detected Using Multiplex PCR in Children After the COVID-19 Pandemic.

In this retrospective single-centred cohort study, we investigated pathogens associated with paediatric airway infections during the 2023 surge of respiratory illnesses in Japan. Data from electronic medical records of children who underwent BioFire® Respiratory Panel testing were analysed. Among 228 hospitalized children, 306 pathogens were identified in 188 patients (82.45%), predominantly rhinovirus/enterovirus (RV/EV; 36.93%), respiratory syncytial virus (RSV; 12.75%), adenovirus (12.42%), and parainfluenza virus type 3 (PIV3; 9.48%). RV/EV positivity was linked to higher rates of laboured breathing (25.34% vs 7.47%, P < .0001) and wheezing (26.03% vs 10.34%, P = .0003). RSV-positivity was associated with increased rhonchi (16.67% vs 3.40%, P = .0009) and crackles (22.22% vs 7.52%, P = .025). Patients with RSV and PIV3 had significantly lower transcutaneous oxygen saturation than those with other viruses. RV/EV were the most prevalent pathogens, underscoring the need for vigilance regarding viruses causing respiratory distress and hypoxemia in children.