{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,27]],"date-time":"2026-03-27T12:07:11Z","timestamp":1774613231541,"version":"3.50.1"},"reference-count":55,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,3,27]],"date-time":"2026-03-27T00:00:00Z","timestamp":1774569600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Merck Sharp & Dohme LLC\n\t\t\t\t\t\t\t\t\t\t              https:\/\/ror.org\/01eqvd516"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Objectives: Despite vaccination being the most effective way of preventing infections and vaccination rates recovering worldwide after the COVID-19 pandemic, vaccine hesitancy persists. Some factors, such as psychological and social barriers, can negatively impact views on vaccines and can contribute to vaccine hesitancy. The primary objective of this structured literature review is to investigate the available evidence relating to factors affecting vaccine hesitancy within several countries in Southeastern Europe. Methods: An electronic database search was conducted to identify studies assessing the public and healthcare professionals\u2019 (HCPs) attitudes towards vaccination in Southeastern Europe. These searches were supplemented with grey literature searches. Included studies were conducted in Bulgaria, Croatia, Romania, Serbia, and Slovenia between 1 January 2012 and 31 December 2022. Results: Of the 35 studies identified from the database searches, the most prominent theme observed across Romania, Croatia, and Bulgaria was low confidence in COVID-19 vaccines. Across all age groups, COVID-19 vaccine confidence in these regions was highly dependent on whether individuals thought vaccines were safe and effective, as well as their general trust in vaccines. Confidence in COVID-19 vaccines was seen as relatively high, with attitudes towards routine and elective vaccines being generally positive amongst the general public and HCPs, in Romania, Croatia, Serbia and Slovenia. However, uncertainty around the effectiveness of the vaccine still exists. In Bulgaria, trust in routine and elective vaccines remained low in the general public. Complacency and financial constraints were also identified as underlying causes of vaccine hesitancy. Conclusions: The main cause behind vaccine hesitancy in several countries in Southeastern Europe is distrust in vaccine effectiveness and safety. These key findings can be utilised to support evidence-based decisions regarding where to focus resources to improve public and HCP perception of vaccines in Southeastern Europe.<\/jats:p>","DOI":"10.3390\/vaccines14040299","type":"journal-article","created":{"date-parts":[[2026,3,27]],"date-time":"2026-03-27T11:12:25Z","timestamp":1774609945000},"page":"299","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Vaccine Confidence and Vaccine Hesitancy in Several Countries in Southeastern Europe in Past 10 Years: A Structured Review of Published Literature"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9254-1263","authenticated-orcid":false,"given":"Kaja","family":"Damnjanovi\u0107","sequence":"first","affiliation":[{"name":"Department of Psychology, University of Belgrade, 11000 Belgrade, Serbia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kalin","family":"Djurov","sequence":"additional","affiliation":[{"name":"MSD Bulgaria, 55 Nikola Vaptzarov Blvd.,1407 Sofia, Bulgaria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Matea","family":"Galic","sequence":"additional","affiliation":[{"name":"MSD Croatia, 10010 Zagreb, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bogdan","family":"Lisul","sequence":"additional","affiliation":[{"name":"MSD Serbia, 11070 Belgrade, Serbia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ionut Viorel","family":"Mocanu","sequence":"additional","affiliation":[{"name":"MSD Romania, 013704 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shreya","family":"Shukla","sequence":"additional","affiliation":[{"name":"Adelphi Values PROVE, Bollington SK10 5JB, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ashley","family":"Enstone","sequence":"additional","affiliation":[{"name":"Adelphi Values PROVE, Bollington SK10 5JB, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lisa","family":"Dai","sequence":"additional","affiliation":[{"name":"Adelphi Values PROVE, Bollington SK10 5JB, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2486-9053","authenticated-orcid":false,"given":"Mitja","family":"Vrdelja","sequence":"additional","affiliation":[{"name":"National Institute of Public Health, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6201-848X","authenticated-orcid":false,"given":"Hristiana","family":"Batselova","sequence":"additional","affiliation":[{"name":"Department of Epidemiology and Disaster Medicine, Medical University of Plovdiv, 4002 Plovdiv, Bulgaria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anca","family":"Dr\u0103g\u0103nescu","sequence":"additional","affiliation":[{"name":"National Institute for Infectious Diseases, 050463 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5153-5027","authenticated-orcid":false,"given":"Goran","family":"Te\u0161ovi\u0107","sequence":"additional","affiliation":[{"name":"Pediatric Infectious Diseases Department, University Hospital for Infectious Diseases, University of Zagreb, School of Medicine, 10000 Zagreb, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,27]]},"reference":[{"key":"ref_1","first-page":"59","article-title":"Perceptions and Attitudes of Parents Toward Vaccination of Children in Western Balkan Countries: Trust in the Function of Improving Public Health","volume":"38","author":"Melovic","year":"2021","journal-title":"Balkan Med. 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