Journal of Clinical Medicine Article A Single-Center (Sibiu, Romania), Retrospective Study (March–November 2020) of COVID-19 Clinical and Epidemiological Features in Children Maria Totan 1,2, *, Felicia Gabriela Gligor 1 , Lavinia Duică 1 , Nicolae Grigore 1,3 , Sinziana Silis , teanu 4 , Ionela Maniu 5,6, * and Elisabeta Antonescu 1,3   Citation: Totan, M.; Gligor, F.G.; Duic˘ a, L.; Grigore, N.; Silis , teanu, S.; Maniu, I.; Antonescu, E. A Single- Center (Sibiu, Romania), Retrospective Study (March– November 2020) of COVID-19 Clinical and Epidemiological Features in Children. J. Clin. Med. 2021, 10, 3517. https://doi.org/10.3390/ jcm10163517 Academic Editor: Nicola Petrosillo Received: 23 June 2021 Accepted: 6 August 2021 Published: 10 August 2021 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). 1 Faculty of Medicine, Lucian Blaga University of Sibiu, 2A Lucian Blaga Str., 550169 Sibiu, Romania; felicia.gligor@ulbsibiu.ro (F.G.G.); lavinia.duica@ulbsibiu.ro (L.D.); nicolae.grigore@ulbsibiu.ro (N.G.); elisabeta.antonescu@ulbsibiu.ro (E.A.) 2 Clinical Laboratory, Clinical Pediatric Hospital, 2-4 Pompeiu Onofreiu Str., 550166 Sibiu, Romania 3 County Clinical Emergency Hospital, 2-4 Corneliu Coposu Str., 550245 Sibiu, Romania 4 Department of Health and Human Development, Stefan cel Mare University of Suceava, 13 University Str., 720229 Suceava, Romania; sinziana.silisteanu@usm.ro 5 Research Team, Pediatric Clinical Hospital Sibiu, 550166 Sibiu, Romania 6 Research Center in Informatics and Information Technology, Mathematics and Informatics Department, Faculty of Sciences, “Lucian Blaga” University of Sibiu, 550025 Sibiu, Romania * Correspondence: maria.totan@ulbsibiu.ro (M.T.); ionela.maniu@ulbsibiu.ro (I.M.) Abstract: The aim of this study was to describe and analyze epidemiological and clinical features of children screened for COVID-19 at Sibiu Pediatric Clinical Hospital during the first 9 months (March–November) of coronavirus disease pandemic in Romania. A total of 203 pediatric patients with a confirmed diagnosis of COVID-19 were included in the study. The median age of the patients was 121 (IQR 18–181) months and 52.22% had mild clinical type with pneumonia, 35.47% were moderate cases, 3.94% severe cases, 0.99% critically ill cases and 7.39% were asymptomatic. The most common symptoms were fever (n = 130, 64.03%), nasal congestion (n = 138, 67.98%), cough (n = 128, 63.05%) followed by sore throat (n = 64, 31.52%), rhinorrhea (n = 63, 31.03%), fatigue (n = 57, 28.07%), headache (n = 47, 23.15%), diarrhea (n = 39, 19.21%), vomiting (n = 32, 15.76%), myalgia (n = 24, 11.82%), abdominal pain (n = 22, 10.83%). A higher proportion of infants with severe or critical disease was encountered with lymphopenia (n = 9, 90%), neutrophilia (n=5, 50%), leukocytosis (n=5, 50%) compared with asymptomatic infants (n = 10, 66.67%, n = 1, 6.67%, n = 3, 20%) or mild (n = 53, 50%, n = 19, 17.92%, n = 15, 14.15%) and moderate (n = 37, 51.39%, n = 9, 12.50%, n = 6, 8.33%) cases (p = 0.095, p = 0.042, p = 0.034). Pediatric patients generally had mild or moderate type of COVID-19, and the critically ill cases were rare. In our study, frequent symptoms were observed in both the systemic and respiratory systems, ear, nose and throat system, and less from gastrointestinal system, central nervous system or ocular system. Additionally, there is an increase in liver and myocardial enzyme levels with an increase in disease severity. Understanding the clinical and laboratory characteristics of pediatric patients is important for diagnosis, management and effective control of the disease. Keywords: coronavirus; COVID-19; SARS-CoV-2; children; pediatric; clinical features; epidemiology 1. Introduction SARS-COV-2 (severe acute respiratory syndrome coronavirus 2) virus is a new type of coronavirus and was identified as the cause of an outbreak of pneumonia in China in late 2019 [1–4]. The epidemic has spread worldwide despite efforts to limit it [2,5–8]. The main route of transmission of the virus is the respiratory tract, through the respi- ratory droplets, the incubation period being between 5 and 14 days [1]. Symptomatology of the disease is predominantly respiratory (fever, cough, difficulty breathing) [9,10]. The J. Clin. Med. 2021, 10, 3517. https://doi.org/10.3390/jcm10163517 https://www.mdpi.com/journal/jcm