Symptom Spectrum and Risk Factors for Fever in Pediatric Patients with Omicron Infection: A Prospective Observational Study

Objective: The omicron variant of coronavirus disease 2019 (COVID-19) has caused a global epidemic in 2022. Our aim was to investigate the symptom spectrum and risk factors for fever in pediatric patients with omicron infection. Methods: From April 8, 2022, to May 17, 2022, this prospective observational study included pediatric patients who attended the child-parent sections of the Fangcang shelter hospitals with laboratory-confirmed COVID-19. Patient data were collected from questionnaires. The risk factors for prolonged fever and high fever were identified by univariate and multivariate analyses. Results: In total, 1,541 pediatric patients were included. The most common symptoms associated with Omicron infection were those affecting the upper respiratory tract. However, gastrointestinal symptoms such as vomiting (11.2%) and diarrhea (7.3%), and lower respiratory symptoms such as wheeze (2.8%), polypnea (2.1%), and chest tightness (2.1%) were present in a non-negligible proportion of cases. The use of antipyretic medicine was independent risk factor for prolonged fever (odds ratio (OR) 1.475, 95% confidence interval (CI): 1.010-2.155, P=0.044) and high fever (OR 3.254, 95% CI: 2.339-4.527, P<0.001). COVID-19 vaccination (OR 0.515, 95% CI: 0.347-0.764, P=0.001) was independently associated with a decreased risk for high fever. Conclusions: In addition to upper respiratory tract infection symptoms, recognition should be given to gastrointestinal and lower respiratory symptoms caused by omicron. Antipyretic administration to manage fever in pediatric patients with the Omicron variant should be undertaken with caution. COVID-19 vaccination may help mitigate high fever.