Characteristics of SARS-CoV-2 Omicron BA.2 Outbreak in Taiwan: Impact on a Pediatric Emergency Department

Background: The Omicron BA.2 outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) began in Taiwan in April 2022. We report the changes and impact that occurred during this outbreak at a pediatric emergency center.Methods: Information was collected regarding patients in the pediatric emergency department between April and July 2022 during the SARS-CoV-2 Omicron BA.2 outbreak. The data were compared with the data from SARS-CoV-2 Alpha variant outbreak during the same period in 2021 (April to July 2021).Findings: Overall, 10,878 children were enrolled, and 7047 (64.8%) children were positive for SARS-CoV-2 infection. They had a mean ± SD age of 5.3 ± 4.1 years. The rates of patients with Pediatric Taiwan Triage (Ped-TTAS) and Acuity Scale level 1 (most urgent) (12.3%) and level 2 (27.6%) were increased, and more children were triaged as most urgent during the period of the Omicron BA.2 outbreak compared to the Alpha variant outbreak (p < 0.001). Fever was the most common symptom (96.6%) in those with SARS-CoV-2 Omicron BA.2 infection, and the proportions of patients with the infection presenting with hyperpyrexia, croup, dyspnea, febrile seizures, headache, dizziness, and myalgia were significantly higher than those without (all p < 0.001). Twenty-five (0.4%) patients required pediatric intensive care and 11 (44.0%) of them were admitted due to encephalopathy or encephalitis. All patients admitted to the intensive care unit were treated with remdesivir on the first day of admission, systemic steroids were administered in 24 (96.0%), and intravenous immune globulins to 11 (44.0%). Three (0.04%) patients died due to fulminant encephalitis, encephalitis with septic shock, and respiratory failure.Interpretation: The number of patients triaged by Ped-TTAS as most urgent increased during this SARS-CoV-2 Omicron BA.2 outbreak. The hyperpyrexia syndrome including high fever, dyspnea, febrile seizures, headache, dizziness, and myalgia was more common in children with the infection. The pressure to a PED was not only from increased visits but also from the level of severity by triage. This study provides special insights into the main causes of increased admittance to PEDs in East Asia, particularly Taiwan.Funding Information: This study was in part support by a grant (111-2321-B-182-001) from the National Science and Technology Council, Executive Yuan, Taiwan.Declaration of Interests: All authors declare that they have no competing of interest.Ethical Approval: All methods were carried out in accordance with the relevant guidelines and regulations in accordance with the Declaration of Helsinki. The need to obtain informed consent from participants was waived because this is a purely retrospective study that does not affect patient care. The study was approved by the Ethics Committee on Human Studies at Chang Gung Memorial Hospital, in Taiwan (No. 202201689B0).