{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,15]],"date-time":"2026-07-15T14:09:34Z","timestamp":1784124574482,"version":"3.55.0"},"reference-count":47,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2025,6,13]],"date-time":"2025-06-13T00:00:00Z","timestamp":1749772800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Children"],"abstract":"<jats:p>Background: Parvovirus B19 is the major cause of transient aplastic crisis in children with hereditary spherocytosis (HS) inhibiting erythropoiesis and leading to a severe drop in hemoglobin levels, requiring hospitalization and transfusional support. During the COVID-19 pandemic, the circulation of non-COVID respiratory viruses, such as parvovirus B19, initially declined but subsequently increased abruptly following the relaxation of containment strategies. Moreover, it remains unclear whether this has resulted in a rise in parvovirus B19-induced aplastic crises among individuals with HS. Methods: This retrospective, single-center study conducted at the Pediatric University Hospital of Bari (Italy) aims to describe the clinical characteristics and frequency of parvovirus B19-induced aplastic crises in pediatric patients with HS before and after the COVID-19 Public Health Emergency of International Concern (PHEIC, 30 January 2020\u20135 May 2023). The study was divided into four distinct periods: Period A: from 1 December 2018 to 31 December 2019, representing one year before the declaration of the PHEIC; Period B: from 1 June 2023 to 30 June 2024, representing one year after the cessation of the PHEIC; Period C: before 1 December 2018; Period D: from 1 January 2020 to 31 May 2023, which refers to the pandemic period. Results: A total of 30 patients (55% of the study population, n = 55) experienced a parvovirus B19-induced aplastic crisis. The frequency of these crises in Period B was significantly higher than in Period A (p &lt; 0.0001). Conclusions: This study suggests a substantial increase in parvovirus B19-induced aplastic crises among children with HS following the COVID-19 outbreak indicating a potential impact of public health containment strategies on parvovirus B19 infection rates.<\/jats:p>","DOI":"10.3390\/children12060772","type":"journal-article","created":{"date-parts":[[2025,6,16]],"date-time":"2025-06-16T14:03:11Z","timestamp":1750082591000},"page":"772","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["An Epidemic of Parvovirus B19-Induced Aplastic Crises in Pediatric Patients with Hereditary Spherocytosis Following the COVID-19 Pandemic: A Single-Center Retrospective Study"],"prefix":"10.3390","volume":"12","author":[{"given":"Paola","family":"Giordano","sequence":"first","affiliation":[{"name":"Pediatric Unit \u201cB. Trambusti\u201d, Interdisciplinary Department of Medicine, University of Bari Aldo Moro, 70121 Bari, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3976-6463","authenticated-orcid":false,"given":"Valentina","family":"Palladino","sequence":"additional","affiliation":[{"name":"Pediatric Unit \u201cB. Trambusti\u201d, Interdisciplinary Department of Medicine, University of Bari Aldo Moro, 70121 Bari, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giuseppe","family":"Lassandro","sequence":"additional","affiliation":[{"name":"Pediatric Unit \u201cB. Trambusti\u201d, Interdisciplinary Department of Medicine, University of Bari Aldo Moro, 70121 Bari, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-0328-7822","authenticated-orcid":false,"given":"Stella","family":"Spina","sequence":"additional","affiliation":[{"name":"Pediatric Unit \u201cB. Trambusti\u201d, Interdisciplinary Department of Medicine, University of Bari Aldo Moro, 70121 Bari, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5462-0027","authenticated-orcid":false,"given":"Giovanni Carlo","family":"Del Vecchio","sequence":"additional","affiliation":[{"name":"Pediatric Unit \u201cB. Trambusti\u201d, Interdisciplinary Department of Medicine, University of Bari Aldo Moro, 70121 Bari, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,13]]},"reference":[{"key":"ref_1","unstructured":"Zamora, E.A., and Schaefer, C.A. (2024). Hereditary Spherocytosis. StatPearls, StatPearls Publishing."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"110","DOI":"10.21614\/chirurgia.112.2.110","article-title":"Hereditary Spherocytosis\u2014Diagnosis, Surgical Treatment and Outcomes. 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