BackgroundSince the outbreak of Coronavirus Disease 2019 (COVID-19) in Wuhan, considerable attention has been paid to its epidemiology and clinical characteristics in children. However, it is also crucial for clinicians to differentiate COVID-19 from other respiratory infectious diseases, such as influenza viruses.MethodsThis was a retrospective study. Two groups of COVID-19 patients (n = 57) and influenza A patients (n = 59) were enrolled. We analyzed and compared their clinical manifestations, imaging characteristics and treatments.ResultsThe proportions of cough (70.2%), fever (54.4%) and gastrointestinal symptoms (14.1%) in COVID-19 patients were lower than those of influenza A patients (98.3%, P < 0.001; 84.7%, P < 0.001; and 35.6%, P = 0.007; respectively). In addition, COVID-19 patients showed significantly lower levels of leukocytes (7.87 vs. 9.89 × 109 L–1, P = 0.027), neutrophils (2.43 vs. 5.16 × 109 L–1, P < 0.001), C-reactive protein (CRP; 3.7 vs. 15.1 mg/L, P = 0.001) and procalcitonin (PCT; 0.09 vs. 0.68 mm/h, P < 0.001), while lymphocyte levels (4.58 vs. 3.56 × 109 L–1; P = 0.006) were significantly higher compared with influenza A patients. In terms of CT imaging, ground-glass opacification in chest CT was more common in COVID-19 patients than in influenza A patients (42.1% vs. 15%, P = 0.032). In contrast, consolidation was more common in influenza A patients (25%) than in COVID-19 patients (5.2%, P = 0.025).ConclusionThe clinical manifestations and laboratory tests of COVID-19 children are milder than those of influenza A children under 5 years. Additionally, imaging results more commonly presented as ground-glass opacities in COVID-19 patients.