{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:38:37Z","timestamp":1760146717635,"version":"build-2065373602"},"reference-count":43,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2024,12,3]],"date-time":"2024-12-03T00:00:00Z","timestamp":1733184000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Background: Patients receiving heart transplantation require lifelong immunosuppression and compared to the general population, they have a more than five times higher chance of acquiring COVID-19, and their mortality rates are higher. The aim of the present study was to estimate the epidemiological and clinical characteristics of COVID-19 in heart transplant recipients (HTRs) in Slovenia to estimate the vaccination rate and evaluate possible vaccination-hesitant subgroups. Methods: All SARS-CoV-2-positive HTRs (N = 79) between 1 March 2020 and 31 December 2023 at the Infectious Diseases Department, University Medical Centre Ljubljana, Slovenia, were included retrospectively. Demographic, clinical and vaccination data were extracted from medical documentation and a statistical evaluation was performed. Results: The observed vaccination rate was 63.3%, but among patients who received transplants before the pandemic, it was statistically significantly higher (p = 0.027). Vaccinated HTRs were statistically significantly older (p = 0.004) and had a significantly higher Charlson Comorbidity Index (p = 0.018). Our results indicate no significant differences between vaccinated and unvaccinated HTRs regarding acute respiratory insufficiency (p = 0.135), length of hospital stay (p = 0.106), intensive care unit admission (0.414) and in-hospital mortality (p = 0.317), but we observed statistically more frequently an asymptomatic course in those vaccinated (p = 0.050), and a longer length of stay in vector vaccine recipients (p = 0.011) and in those not re-vaccinated (p = 0.030). There was a significantly higher re-vaccination rate in males (p = 0.005). Conclusions: An asymptomatic course of COVID-19 was more often observed in vaccinated HTRs. Our findings suggest statistically significant differences in COVID-19 vaccine acceptance rates; younger HTRs and those transplanted after the pandemic are more hesitant to vaccinate, while females accept booster doses less frequently.<\/jats:p>","DOI":"10.3390\/vaccines12121366","type":"journal-article","created":{"date-parts":[[2024,12,3]],"date-time":"2024-12-03T04:01:29Z","timestamp":1733198489000},"page":"1366","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Epidemiological and Clinical Characteristics of the Course of COVID-19 Among Vaccinated and Unvaccinated Heart Transplant Recipients in Slovenia"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7415-123X","authenticated-orcid":false,"given":"Nina","family":"Grasselli Kmet","sequence":"first","affiliation":[{"name":"Infectious Diseases Department, University Medical Centre Ljubljana, 1000 Ljubljana, Slovenia"},{"name":"Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Matej","family":"Mavri\u010d","sequence":"additional","affiliation":[{"name":"Infectious Diseases Department, University Medical Centre Ljubljana, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rajko","family":"Saletinger","sequence":"additional","affiliation":[{"name":"Infectious Diseases Department, University Medical Centre Ljubljana, 1000 Ljubljana, Slovenia"},{"name":"Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,12,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e224","DOI":"10.1093\/eurjpc\/zwab175","article-title":"Incidence and prognosis of COVID-19 amongst heart transplant recipients: A systematic review and meta-analysis","volume":"29","author":"Ahmed","year":"2022","journal-title":"Eur. 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