Distinctive clinical and laboratory features of COVID-19 and H1N1 influenza infections among hospitalized pediatric patients

Background: It had been documented in many studies that pediatric coronavirus disease 2019 (COVID-19) is characterized by low infectivity rates, low mortalities, and benign disease course. On the other hand, influenza type A viruses are recognized to cause severe and fatal infections in children populations worldwide. This study is aimed to compare the clinical and laboratory characteristics of COVID-19 and H1N1 influenza infections. Methods: A retrospective study comprising 107 children hospitalized at Abha Maternity and Children Hospital, Southern region of Saudi Arabia, with laboratory-confirmed COVID-19 and H1N1 influenza infections was carried out. A complete follow-up for all patients from the hospital admission until discharge or death was made. The clinical data and laboratory parameters for these patients were collected from the medical records of the hospital. Results: Out of the total enrolled patients, 73 (68.2%) were diagnosed with COVID-19, and 34 (31.8%) were diagnosed with H1N1 influenza. The median age is 12 months for COVID-19 patients and 36 months for influenza patients. A relatively higher number of patients with influenza had a fever and respiratory symptoms than COVID-19 patients. In contrast, gastrointestinal symptoms were observed in a higher number of COVID-19 patients than in influenza patients. A statistically significant increase in white cell counts is noted in COVID-19 but not in influenza patients (P < 0.05). There are no obvious variations in the mean period of duration of hospitalization between COVID-19 and influenza patients. However, the total intensive care unit length of stay was longer for influenza compared to COVID-19 patients. Conclusions: A considerable number of children infected with COVID-19 and H1N1 influenza were noted and reported in this study. There were no significant variations in the severity of the symptomatology and laboratory findings between the two groups of patients. Significant differences between these patients in some hospitalization factors and diagnosis upon admission also were not observed. However, more severe clinical manifestations and serious consequences were observed among pediatric patients hospitalized with influenza infections than among those with COVID-19.