{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:18:57Z","timestamp":1760059137080,"version":"build-2065373602"},"reference-count":28,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2025,5,22]],"date-time":"2025-05-22T00:00:00Z","timestamp":1747872000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Background\/Objectives: Our study aimed to assess longitudinal trends in blood culture contamination in a regional secondary care teaching hospital before and after the COVID-19 pandemic and to evaluate differences in the interpretation of trends using two distinct quasi-experimental statistical methods, including interrupted time-series analysis. Methods: We analyzed data from a 10-year period spanning from 2015 to 2024, encompassing 147,733 admissions and 634,158 patient-days, as well as a total of 25,068 blood cultures. The (i) blood culture contamination rate, (ii) contaminant proportion, (iii) single blood culture rate, and (iv) first-to-second bottle contamination ratio were calculated. Results: The observed usage rate of blood cultures per 1000 patient-days was 38.9. The contamination rate of blood cultures increased from 0.9% to 1.5% (p = 0.001) in the post-COVID-19 period, accompanied by a rise in the proportion of contaminant bacteria from 9.8% to 14.2% (p = 0.016). Additionally, the proportion of single blood culture collections increased from 23.1% to 33.6% (p &lt; 0.001). Finally, the overall first-to-second bottle contamination ratio was 1.54, while the ratio in the post-COVID-19 period was 1.92. Conclusions: In a low-COVID-19-burden secondary care teaching hospital setting, blood culture contamination rates have progressively increased over the past decade, irrespective of the pandemic. These findings underscore the importance of sustained vigilance in infection prevention and control practices, strict adherence to blood culture collection protocols, and the ongoing need for staff training.<\/jats:p>","DOI":"10.3390\/antibiotics14060533","type":"journal-article","created":{"date-parts":[[2025,5,22]],"date-time":"2025-05-22T10:24:45Z","timestamp":1747909485000},"page":"533","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Blood Culture Contamination Creep Independent of COVID-19 Pandemics: An Interrupted Time-Series Analysis"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8373-8080","authenticated-orcid":false,"given":"Samo","family":"Jeverica","sequence":"first","affiliation":[{"name":"Izola General Hospital, 6310 Izola, Slovenia"},{"name":"Faculty of Health Sciences, University of Primorska, 6000 Koper, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jani","family":"Derni\u010d","sequence":"additional","affiliation":[{"name":"Izola General Hospital, 6310 Izola, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Peter","family":"Golob","sequence":"additional","affiliation":[{"name":"Izola General Hospital, 6310 Izola, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alenka","family":"Stepi\u0161nik","sequence":"additional","affiliation":[{"name":"Izola General Hospital, 6310 Izola, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bojan","family":"Novak","sequence":"additional","affiliation":[{"name":"Izola General Hospital, 6310 Izola, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Toma\u017e","family":"Gantar","sequence":"additional","affiliation":[{"name":"Izola General Hospital, 6310 Izola, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0746-1865","authenticated-orcid":false,"given":"Lea","family":"Papst","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases, University Medical Centre Ljubljana, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anamarija Juri\u0161evi\u010d","family":"Dodi\u010d","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology Koper, National Laboratory of Health, Environment and Food, 2000 Maribor, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4012-787X","authenticated-orcid":false,"given":"Darja Barli\u010d","family":"Maganja","sequence":"additional","affiliation":[{"name":"Faculty of Health Sciences, University of Primorska, 6000 Koper, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4169-2122","authenticated-orcid":false,"given":"Jan","family":"Zmazek","sequence":"additional","affiliation":[{"name":"Faculty of Natural Sciences and Mathematics, University of Maribor, 2000 Maribor, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mladen","family":"Gasparini","sequence":"additional","affiliation":[{"name":"Izola General Hospital, 6310 Izola, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"200","DOI":"10.1016\/S0140-6736(19)32989-7","article-title":"Global, Regional, and National Sepsis Incidence and Mortality, 1990\u20132017: Analysis for the Global Burden of Disease Study","volume":"395","author":"Rudd","year":"2020","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"e00009-19","DOI":"10.1128\/CMR.00009-19","article-title":"Practical Guidance for Clinical Microbiology Laboratories: A Comprehensive Update on the Problem of Blood Culture Contamination and a Discussion of Methods for Addressing the Problem","volume":"33","author":"Doern","year":"2019","journal-title":"Clin. 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