{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T22:07:03Z","timestamp":1792793223091,"version":"4.5.0"},"reference-count":29,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2024,12,13]],"date-time":"2024-12-13T00:00:00Z","timestamp":1734048000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Objectives of the study: The aim of this study was to assess the impact of the COVID-19 pandemic on the epidemiology and clinical course of chickenpox in children based on 6 years of self-reported observations. MATERIAL AND METHODS: The medical records of 350 patients under 18 years of age hospitalised in the Department of Paediatrics, Infectious Diseases, and Hepatology between 1 January 2018 to 31 December 2023 were analysed retrospectively. RESULTS: During the analysed period, 350 children were hospitalised due to chickenpox, the fewest in the pandemic period, the greatest number in 2023. Complications of chickenpox were diagnosed in 297 children (84.86%). The most commonly diagnosed complications were bacterial dermatitis (168, 48%) and lower respiratory tract infections (13.42%). After the pandemic period, a generalised inflammatory reaction was observed significantly more often (p \u2264 0.01069). Among children hospitalised in 2023, 5.90% of patients with bacterial dermatitis required surgical intervention due to skin abscess or fasciitis. In 2023, 41.46% of cultures from swabs taken from skin lesions grew Streptococcus pyogenes. After the pandemic, children with chickenpox and gastrointestinal symptoms were hospitalised significantly less frequently (p \u2264 0.00001). CONCLUSIONS: In the post-pandemic period, there were more hospitalisations of patients with chickenpox complicated by bacterial skin infection progressing to a generalised inflammatory reaction or septicaemia, related to the increase in invasive group A streptococcal infections observed in Europe. On the other hand, thanks to the widespread adaption of hygiene practices and infection prevention measures, the number of patients with gastrointestinal symptoms significantly decreased.<\/jats:p>","DOI":"10.3390\/v16121912","type":"journal-article","created":{"date-parts":[[2024,12,13]],"date-time":"2024-12-13T03:51:08Z","timestamp":1734061868000},"page":"1912","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Has COVID-19 Affected the Course of Chickenpox in Children?"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-5144-9513","authenticated-orcid":false,"given":"Justyna","family":"Franczak","sequence":"first","affiliation":[{"name":"Department of Infectious Diseases and Hepatology, Collegium Medicum, Bydgoszcz, Nicolaus Copernicus University, 87-100 Torun, Poland"},{"name":"Department of Paediatrics, Infectious Diseases and Hepatology, Voivodeship Infectious Observation Hospital, 85-030 Bydgoszcz, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zuzanna","family":"Wasielewska","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases and Hepatology, Collegium Medicum, Bydgoszcz, Nicolaus Copernicus University, 87-100 Torun, Poland"},{"name":"Department of Paediatrics, Infectious Diseases and Hepatology, Voivodeship Infectious Observation Hospital, 85-030 Bydgoszcz, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna Maria","family":"Fotyga","sequence":"additional","affiliation":[{"name":"Department of Paediatrics, Infectious Diseases and Hepatology, Voivodeship Infectious Observation Hospital, 85-030 Bydgoszcz, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Krystyna","family":"Dobrowolska","sequence":"additional","affiliation":[{"name":"Collegium Medicum, Jan Kochanowski University, 25-317 Kielce, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6299-2103","authenticated-orcid":false,"given":"Justyna","family":"Moppert","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases and Hepatology, Collegium Medicum, Bydgoszcz, Nicolaus Copernicus University, 87-100 Torun, Poland"},{"name":"Department of Paediatrics, Infectious Diseases and Hepatology, Voivodeship Infectious Observation Hospital, 85-030 Bydgoszcz, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ma\u0142gorzata","family":"Sobolewska-Pilarczyk","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases and Hepatology, Collegium Medicum, Bydgoszcz, Nicolaus Copernicus University, 87-100 Torun, Poland"},{"name":"Department of Paediatrics, Infectious Diseases and Hepatology, Voivodeship Infectious Observation Hospital, 85-030 Bydgoszcz, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6044-0425","authenticated-orcid":false,"given":"Ma\u0142gorzata","family":"Paw\u0142owska","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases and Hepatology, Collegium Medicum, Bydgoszcz, Nicolaus Copernicus University, 87-100 Torun, Poland"},{"name":"Department of Paediatrics, Infectious Diseases and Hepatology, Voivodeship Infectious Observation Hospital, 85-030 Bydgoszcz, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,12,13]]},"reference":[{"key":"ref_1","unstructured":"Milewska-Bobula, B., and Lipka, B. (2024, August 01). Ospa Wietrzna [Chickenpox]. Medycyna Praktyczna [Practical Medicine]. 10 November 2016. Available online: https:\/\/www.mp.pl\/pacjent\/pediatria\/choroby\/chorobyzakazne\/67573,ospa-wietrzna."},{"key":"ref_2","first-page":"10","article-title":"Ospa wietrzna [Chickenpox]","volume":"16","year":"2012","journal-title":"Pediatr. Dypl."},{"key":"ref_3","first-page":"477","article-title":"Varicella and shingles\u2014Clinical presentation and possibility of prevention","volume":"4","author":"Siewert","year":"2018","journal-title":"Lekarz POZ"},{"key":"ref_4","unstructured":"National Institute of Public Health (2024, August 05). Infectious Diseases and Poisonings in Poland in 2018\u20132023, Available online: https:\/\/wwwold.pzh.gov.pl\/oldpage\/epimeld\/index_p.html#0."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"459","DOI":"10.32394\/pe.72.4.21","article-title":"Varicella complications in children one-site Polish population\u2014A 19-year long survey","volume":"72","author":"Smok","year":"2018","journal-title":"Przegl\u0105d Epidemiol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1673","DOI":"10.1007\/s10389-022-01731-1","article-title":"Influence of the COVID-19 pandemic measures on incidence and representation of other infectious diseases in Germany: A lesson to be learnt","volume":"31","author":"Kaatz","year":"2023","journal-title":"J. Public Health"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"844","DOI":"10.1002\/iid3.352","article-title":"The impact of COVID-19 control measures on the morbidity of varicella, herpes zoster, rubella and measles in Guangzhou, China","volume":"8","author":"Wu","year":"2020","journal-title":"Immun. Inflamm. Dis."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Sabale, U., Jarmale, L., Murtagh, J., Pawaskar, M., and Bencina, G. (2023). Impact assessment of immunization and the COVID-19 pandemic on varicella across Europe using digital epidemiology methods: A descriptive study. PLoS ONE, 18.","DOI":"10.1371\/journal.pone.0283465"},{"key":"ref_9","unstructured":"Wikipedia (2024, August 05). Pandemia COVID-19 w Polsce. Available online: https:\/\/pl.wikipedia.org\/wiki\/Pandemia_COVID-19_w_Polsce."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Franczak, J., Moppert, J., Sobolewska-Pilarczyk, M., and Paw\u0142owska, M. (2022). The Seroprevalence of SARS-CoV-2 IgG Antibodies in Children Hospitalized for Reasons Other Than COVID-19. J. Clin. Med., 11.","DOI":"10.3390\/jcm11133819"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"451","DOI":"10.3390\/pediatric16020039","article-title":"Impact of COVID-19 Pandemic on the Clinical Course and Complications of Varicella-A Retrospective Cohort Study","volume":"16","author":"Pietrzak","year":"2024","journal-title":"Pediatr. Rep."},{"key":"ref_12","first-page":"2300355","article-title":"Obci\u0105\u017cenie powik\u0142a\u0144 ospy wietrznej w Polsce, od 2006 do 2021 roku: Kompleksowe badanie oparte na rejestrze [The burden of chickenpox complications in Poland, from 2006 to 2021: A comprehensive registry-based study]","volume":"29","author":"Halik","year":"2024","journal-title":"Eurosurveillance"},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Wysocki, J., Malecka, I., Stryczynska-Kazubska, J., Rampakakis, E., Kuter, B., and Wolfson, L.J. (2018). Varicella in Poland: Economic burden in children 1\u201312 years of age in Poland, 2010\u20132015. BMC Public Health, 18.","DOI":"10.1186\/s12889-018-5298-8"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"4958","DOI":"10.1016\/j.vaccine.2023.06.054","article-title":"Impacts of routine varicella vaccination program and COVID-19 pandemic on varicella and herpes zoster incidence and health resource use among children in Japan","volume":"41","author":"Uda","year":"2023","journal-title":"Vaccine"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1756","DOI":"10.55730\/1300-0144.5745","article-title":"Positive effects of health behaviours acquired during the COVID-19 pandemic process on the prevention of other infectious diseases","volume":"53","author":"Buzgan","year":"2023","journal-title":"Turk. J. Med. Sci."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"766","DOI":"10.1097\/INF.0000000000003982","article-title":"Changing Patterns of Infectious Diseases Among Hospitalized Children in Hokkaido, Japan, in the Post-COVID-19 Era, July 2019 to June 2022","volume":"42","author":"Fukuda","year":"2023","journal-title":"Pediatr. Infect. Dis. J."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1001","DOI":"10.1007\/s00431-023-05210-x","article-title":"Effect of the COVID-19 pandemic on the pediatric infectious disease landscape","volume":"183","author":"Shmueli","year":"2024","journal-title":"Eur. J. Pediatr."},{"key":"ref_18","first-page":"E274","article-title":"Impact of the COVID-19 pandemic on the infectious disease epidemiology","volume":"64","author":"Genovese","year":"2023","journal-title":"J. Prev. Med. Hyg."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"489","DOI":"10.32394\/pe.77.40","article-title":"Chickenpox in Poland in 2021","volume":"77","author":"Bogusz","year":"2023","journal-title":"Przegl\u0105d Epidemiol.-Epidemiol. Rev."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"88","DOI":"10.1016\/j.eimc.2023.04.003","article-title":"Streptococcus pyogenes infections in Spanish children before and after the COVID pandemic. Coming back to the previous incidence","volume":"42","author":"Grandioso","year":"2024","journal-title":"Enfermedades Infecc. Microbiol. Clin."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"112","DOI":"10.1016\/S2352-4642(23)00295-X","article-title":"Invasive group A streptococcal infections in children and adolescents in Denmark during 2022\u20132023 compared with 2016\u20132017 to 2021\u20132022: A nationwide, multicentre, population-based cohort study","volume":"8","author":"Nygaard","year":"2024","journal-title":"Lancet Child Adolesc. Health"},{"key":"ref_22","first-page":"351","article-title":"Increases in group A streptococcal infections in the pediatric population in Houston. TX, 2022","volume":"77","author":"Aboulhosn","year":"2023","journal-title":"Clin. Infect. Dis."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"540","DOI":"10.1093\/jpids\/piad080","article-title":"Outbreak of Invasive Group A Streptococcus in Children\u2014Colorado, October 2022\u2013April 2023","volume":"12","author":"Ho","year":"2023","journal-title":"J. Pediatr. Infect. Dis. Soc."},{"key":"ref_24","first-page":"2200941","article-title":"Increase in invasive group A streptococcal (Streptococcus pyogenes) infections (iGAS) in young children in the Netherlands, 2022","volume":"28","author":"Marchal","year":"2023","journal-title":"Eurosurveillance"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"161","DOI":"10.1016\/j.anpedi.2024.01.009","article-title":"Current epidemiological situation of Streptococcus pyogenes infections","volume":"100","author":"Calvo","year":"2024","journal-title":"An. Pediatr."},{"key":"ref_26","first-page":"e002923","article-title":"Clinical, microbiological, and molecular characterization of pediatric invasive infections by Streptococcus pyogenes in Spain in a context of global outbreak","volume":"9","author":"Grandioso","year":"2024","journal-title":"mSphere"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"100597","DOI":"10.1016\/j.lanepe.2023.100597","article-title":"Increasing incidence and severity of invasive Group A streptococcal disease in Spanish children in 2019\u20132022","volume":"27","author":"Calvo","year":"2023","journal-title":"Lancet Reg. Health Eur."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"418","DOI":"10.1016\/j.idnow.2021.05.004","article-title":"Pediatric Infectious Disease Group (GPIP) position paper on the immune debt of the COVID-19 pandemic in childhood, how can we fill the immunity gap?","volume":"51","author":"Cohen","year":"2021","journal-title":"Infect. Dis. 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