{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T11:36:30Z","timestamp":1785411390910,"version":"3.56.0"},"reference-count":46,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T00:00:00Z","timestamp":1779321600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Education and Science","award":["BG-RRP-2.004-0006-C02"],"award-info":[{"award-number":["BG-RRP-2.004-0006-C02"]}]},{"award":["BG-RRP-2.004-0006-C02"],"award-info":[{"award-number":["BG-RRP-2.004-0006-C02"]}],"id":[{"id":"https:\/\/ror.org\/053pcb396","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Healthcare"],"abstract":"<jats:p>Background\/Objectives: The hepatitis A virus (HAV) infection continues to represent a considerable public health issue in Eastern Europe, particularly in Bulgaria, where incidence rates exceed the EU average. This study sought to investigate the epidemiological and clinical aspects of acute hepatitis A in Southern Bulgaria between 2015 and 2023 and to assess changes during the COVID-19 pandemic period. Methods: A retrospective descriptive-analytic study was conducted among 1810 hospitalized patients with confirmed acute HAV infection at a tertiary infectious diseases center from 2015 to 2023. Demographic, clinical, laboratory, and temporal data were analyzed, comparing the pre-pandemic period (2015\u20132019) with the pandemic phase (2020\u20132023). Results: Most hospitalized cases occurred during the pre-pandemic period (88.0%), with epidemic peaks observed in 2016\u20132017. Individuals under 18 years comprised 69.9% of cases, with a median age of 9 years and a slight male predominance of 54.9%. A notable seasonal pattern was identified, characterized by peaks in autumn and early winter. Patients hospitalized during the pandemic period were significantly older compared with the pre-pandemic period (median age 14 vs. 8 years, p &lt; 0.001). Adults experienced significantly longer hospitalization and higher ALT, AST, total bilirubin, and direct bilirubin levels compared with pediatric patients (all p &lt; 0.001). The median duration of hospitalization was 7 days (IQR 6\u201310). Two in-hospital deaths were recorded, corresponding to a case fatality rate of 0.11%. Conclusions: Hepatitis A in Southern Bulgaria mostly impacts children but exhibits changing epidemiological trends, underscoring the necessity for focused preventative methods, such as vaccination and enhanced surveillance.<\/jats:p>","DOI":"10.3390\/healthcare14101428","type":"journal-article","created":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T13:53:24Z","timestamp":1779371604000},"page":"1428","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Single-Center Retrospective Study of Hospitalized Hepatitis A Cases in Southern Bulgaria, 2015\u20132023"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5275-7799","authenticated-orcid":false,"given":"Meri","family":"Hristamyan","sequence":"first","affiliation":[{"name":"Department of Epidemiology and Disaster Medicine, Faculty of Public Health, Medical University of Plovdiv, 4000 Plovdiv, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Simona","family":"Zlatanova","sequence":"additional","affiliation":[{"name":"Clinic of Infectious Diseases and Parasitology, St. George University Hospital, 4000 Plovdiv, Bulgaria"},{"name":"Department of Infectious Diseases, Parasitology and Tropical Medicine, Faculty of Medicine, Medical University of Plovdiv, 4000 Plovdiv, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9270-5996","authenticated-orcid":false,"given":"Vanya","family":"Rangelova","sequence":"additional","affiliation":[{"name":"Department of Epidemiology and Disaster Medicine, Faculty of Public Health, Medical University of Plovdiv, 4000 Plovdiv, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ilia","family":"Tsachev","sequence":"additional","affiliation":[{"name":"Department of Clinical Science, Faculty of Veterinary Medicine, Medical University, 5800 Pleven, Bulgaria"},{"name":"Department of Microbiology, Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria"},{"name":"Department of Agricultural and Forestry Sciences, Bulgarian Academy of Sciences, 1040 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e70838","DOI":"10.1002\/jmv.70838","article-title":"Global, regional, and national time trends in incidence for hepatitis A, 1990\u20132021: A systematic analysis for the Global Burden of Disease 2021 study","volume":"98","author":"Huang","year":"2026","journal-title":"J. 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