References
2. Denny FW, Murphy TF, Clyde WA Jr, Collier AM, Henderson FW. Croup: an 11-year study in a pediatric practice. Pediatrics. 1983; 71:871–876.
4. Lee DR, Lee CH, Won YK, Suh DI, Roh EJ, Lee MH, et al. Clinical characteristics of children and adolescents with croup and epiglottitis who visited 146 Emergency Departments in Korea. Korean J Pediatr. 2015; 58:380–385.
5. Jeon IS, Cho WJ, Lee J, Kim HM. Epidemiology and clinical severity of the hospitalized children with viral Croup. Pediatr Infect Vaccine. 2018; 25:8–16.
6. Kim EJ, Nam H, Sun YH, Tchah H, Ryoo E, Cho HK, et al. Comparison of etiology and clinical presentation between children with laryngotracheo bronchopneumonitis and Croup. Allergy Asthma Respir Dis. 2017; 5:274–279.
7. Lee YJ, Kim HB, Kim BS, Kim CK, Kim CH, Kim HY, et al. Seasonal patterns and etiologies of croup in children during the period 2010-2015: a multicenter retrospective study. Allergy Asthma Respir Dis. 2019; 7:78–85.
8. Abedi GR, Prill MM, Langley GE, Wikswo ME, Weinberg GA, Curns AT, et al. Estimates of parainfluenza virus-associated hospitalizations and cost among children aged less than 5 years in the United States, 1998–2010. J Pediatric Infect Dis Soc. 2016; 5:7–13.
9. Sohn YJ, Choi YY, Yun KW, Choi EH, Lee HJ. Epidemiology and clinical characteristics of parainfluenza virus type 4 in Korean children: a single center study, 2015–2017. Pediatr Infect Vaccine. 2018; 25:156–164.
10. Walsh EE, Shin JH, Falsey AR. Clinical impact of human coronaviruses 229E and OC43 infection in diverse adult populations. J Infect Dis. 2013; 208:1634–1642.
11. Varghese L, Zachariah P, Vargas C, LaRussa P, Demmer RT, Furuya YE, et al. Epidemiology and clinical features of human coronaviruses in the pediatric population. J Pediatric Infect Dis Soc. 2018; 7:151–158.