Acknowledgement
This work was supported by Public Medical Research Institute, Busan Medical Center.
References
- Korea Disease Control and Prevention Agency (KDCA). Surveillance status of COVID-19 positive cases [Internet]. Cheongju: KDCA; 2023 [cited 2023 Sep 17]. Available from: https://ncov.kdca.go.kr/bdBoardListR.do?brdId=1&brdGubun=11.
- World Health Organization (WHO). Tracking SARS-CoV-2 variants [Internet]. Geneva: WHO; 2023 [cited 2023 Oct 8]. Available from: https://www.who.int/activities/tracking-SARS-CoV-2-variants.
- Ryu BY, Shin EJ, Kim NY, Kim DH, Lee HJ, Kim AR. Severity of COVID-19 associated with SARS-CoV-2 variants circulating in the Republic of Korea. Public Health Wkly Rep. 2022;15:2873-83. https://doi.org/10.56786/PHWR.2022.15.47.2873
- Han MS, Kim KM, Oh KJ, Chang JY, Lee SY, Choi JE, et al. Distinct clinical laboratory features of COVID-19 in children during the pre-delta, delta and omicron wave. Pediatr Infect Dis J 2023;42:423-8. https://doi.org/10.1097/INF.0000000000003872
- Ong SW, Chiew CJ, Ang LW, Mak TM, Cui L, Toh MP, et al. Clinical and virological features of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern: a retrospective cohort study comparing B.1.1.7 (alpha), B.1.351 (beta), and B.1.617.2 (delta). Clin Infect Dis 2022;75:e1128-36. https://doi.org/10.1093/cid/ciab721
- Maslo C, Friedland R, Toubkin M, Laubscher A, Akaloo T, Kama B. Characteristics and outcomes of hospitalized patients in South Africa during COVID-19 omicron wave compared with previous waves. JAMA 2022;327:583-4. https://doi.org/10.1001/jama.2021.24868
- Menni C, Valdes AM, Polidori L, Antonelli M, Penamakuri S, Nogal A, et al. Symptom prevalence, duration, and risk of hospital admission in individuals infected with SARS-CoV-2 during periods of omicron and delta variant dominance: a prospective observational study from the ZOE COVID Study. Lancet 2022;399:1618-24. https://doi.org/10.1016/S0140-6736(22)00327-0
- Ding Y, Yan H, Guo W. Clinical characteristics of children with COVID-19:a meta-analysis. Front Pediatr 2020;8:431.
- Kosmeri C, Koumpis E, Tsabouri S, Siomou E, Makis A. Hematological manifestations of SARS-CoV-2 in children. Pediatr Blood Cancer 2020;67:e28745.
- Kim IH, Park AK, Lee H, Kim J, Kim DH, Kim JA, et al. July 2021 status and characteristics of the COVID-19 variant virus outbreak in the republic of Korea. Public Health Wkly Rep 2021;14:3388-96.
- Ahn S, Jang J, Park SY, Yang S, Ryu B, Shin E, et al. Outbreak report of COVID-19 during designation of class 1 infectious disease in the Republic of Korea (January 20, 2020-April 24, 2022). Public Health Wkly Rep 2022;15:2126-36.
- Kang HM, Park JY, Choe YJ. Clinical manifestations, epidemiologic characteristics, and disease Burden of the coronavirus disease-19 in children ages 5-11 years old. Pediatr Infect Vaccine 2022;29:61-9. https://doi.org/10.14776/piv.2022.29.e12
- Kim DH, Han MS, Kim HS, Lim MS, Choo MA, Lee E, et al. Establishment of multicenter cohort research system and analysis of clinical epidemiologic characteristics for children and adolescents with COVID-19. In: Proceedings of the 22th Congress of the Korean Society of Pediatric Infectious Diseases; 2021 Nov 20; Seoul, Korea. Seoul: Korean Society of Pediatric Infectious Diseases; 2021.
- Somekh E, Gleyzer A, Heller E, Lopian M, Kashani-Ligumski L, Czeiger S, et al. The role of children in the dynamics of intra family coronavirus 2019 spread in densely populated area. Pediatr Infect Dis J 2020;39:e202-4. https://doi.org/10.1097/INF.0000000000002783
- Yung CF, Kam KQ, Chong CY, Nadua KD, Li J, Tan NW, et al. Household tranmission of severe acute respiratory syndrome coronavirus 2 from adult to children. J Pediatr 2020;225:249-51. https://doi.org/10.1016/j.jpeds.2020.07.009
- Choi SH, Kim HW, Kang JM, Kim DH, Cho EY. Epidemiology and clinical features of coronavirus disease 2019 in children. Clin Exp Pediatr 2020;63:125-32. https://doi.org/10.3345/cep.2020.00535
- Marks KJ, Whitaker M, Anglin O, Milucky J, Patel K, Pham H, et al. Hospitalizations of children and adolescents with laboratory-confirmed COVID-19 -COVID-NET, 14 States. July 2021- January 2022. MMWR Morb Mortal Wkly Rep 2022;71:271-8. https://doi.org/10.15585/mmwr.mm7107e4
- Molteni E, Sudre CH, Canas LD, Bhopal SS, Hughes RC, Chen L, et al. Illness characteristics of COVID-19 in children infected with the SARS-CoV-2 delta variant. Children (Basel) 2022;9:652.
- Shoji K, Akiyama T, Tsuzuki S, Matsunaga N, Asai Y, Suzuki S, et al. Comparison of the clinical characteristics and outcomes of COVID-19 in children before and after the emergence of delta variant of concern in Japan. J Infect Chemother 2022;28:591-4. https://doi.org/10.1016/j.jiac.2022.01.009
- Zheng F, Liao C, Fan QH, Chen HB, Zhao XG, Xie ZG, et al. Clinical characteristics of children with coronavirus disease 2019 in Hubei, China. Curr Med Sci 2020;40:275-80. https://doi.org/10.1007/s11596-020-2172-6
- Liao D, Zhou F, Luo L, Xu M, Wang H, Xia J, et al. Haematological characteristics and risk factors in the classification and prognosis evaluation of COVID-19: a retrospective cohort study. Lancet Haematol 2020;7:e671-8. https://doi.org/10.1016/S2352-3026(20)30217-9
- Yang X, Yu Y, Xu J, Shu H, Xia J, Liu H, et al. Clinical course and outcomes of critically ill patients with SARS-CoV-2 pneumonia in Wuhan, China: a single-centered, retrospective, observational study. Lancet Respir Med 2020;8:475-81. https://doi.org/10.1016/S2213-2600(20)30079-5
- Terpos E, Ntanasis-Stathopoulos I, Elalamy I, Kastritis E, Sergentanis TN, Politou M, et al. Hematological findings and complications of COVID-19. Am J Hematol 2020;95:834-47. https://doi.org/10.1002/ajh.25829
- Mantovani A, Rinaldi E, Zusi C, Beatrice G, Saccomani MD, Dalbeni A. Coronavirus disease 2019 (COVID-19) in children and/or adolescents: a meta-analysis. Pediatr Res 2021;89:733-7. https://doi.org/10.1038/s41390-020-1015-2
- Henry BM, Benoit SW, de Oliveira MH, Hsieh WC, Benoit J, Ballout RA, et al. Laboratory abnormalities in children with mild and severe coronavirus disease 2019 (COVID-19): a pooled analysis and review. Clin Biochem 2020;81:1-8. https://doi.org/10.1016/j.clinbiochem.2020.05.012
- Folino F, Menis C, Di Pietro GM, Pinzani R, Marchisio P, Bosis S. Incidental occurrence of neutropenia in children hospitalised for COVID-19. Ital J Pediatr 2022;48:43.
- Venturini E, Palmas G, Montagnani C, Chiappini E, Citera F, Astorino V, et al. Severe neutropenia in infants with severe acute respiratory syndrome caused by the novel coronavirus 2019 infection. J Pediatr 2020;222:259-61. https://doi.org/10.1016/j.jpeds.2020.04.051
- Husain EH, Mullah-Ali A, Al-Sharidah S, Azab AF, Adekile A. Infectious etiologies of transient neutropenia in previously healthy children. Pediatr Infect Dis J 2012;31:575-7. https://doi.org/10.1097/INF.0b013e318250084a