{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T19:06:58Z","timestamp":1783624018308,"version":"3.55.0"},"reference-count":36,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2024,9,2]],"date-time":"2024-09-02T00:00:00Z","timestamp":1725235200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003336","name":"Bulgarian national science fund","doi-asserted-by":"publisher","award":["KP06-N-73\/4"],"award-info":[{"award-number":["KP06-N-73\/4"]}],"id":[{"id":"10.13039\/501100003336","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Lyme borreliosis (LB), a tick-borne infection caused by bacteria in the Borrelia burgdorferi sensu lato complex, is increasingly prevalent on the Balkan Peninsula, including Bulgaria, where it is the most common tick-borne disease. This study aimed to assess the seroprevalence of LB across Bulgaria by analyzing 1892 serum samples for specific IgG antibodies using a two-tier testing protocol involving an ELISA and immunoblot methods. The results revealed an overall seroprevalence rate of 5.4%, with significant variation based on age, sex, and residence. Seroprevalence increased with age, peaking at 8.4% in individuals over 65 years. Males had a seroprevalence of 8.4% compared to 3.3% in females, and rural residents showed higher seroprevalence (10.2%) compared to urban residents (4.4%). Regional analysis indicated that seroprevalence ranged from 0.0% to 20.0%, with higher rates in northern provinces such as Gabrovo (18.9%) and Targovishte (20.0%). This study highlights the importance of two-step testing protocols for accurate diagnosis and underscores the need for increased awareness and further research to enhance public health measures and the management of LB in Bulgaria.<\/jats:p>","DOI":"10.3390\/pathogens13090754","type":"journal-article","created":{"date-parts":[[2024,9,2]],"date-time":"2024-09-02T12:54:42Z","timestamp":1725281682000},"page":"754","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Serological Assessment of Lyme borreliosis in Bulgaria: A Nationwide Study"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8390-9970","authenticated-orcid":false,"given":"Kim","family":"Ngoc","sequence":"first","affiliation":[{"name":"Department of Microbiology, National Center of Infectious and Parasitic Diseases, 1504 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7320-9548","authenticated-orcid":false,"given":"Iva","family":"Trifonova","sequence":"additional","affiliation":[{"name":"Department of Microbiology, National Center of Infectious and Parasitic Diseases, 1504 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Teodora","family":"Gladnishka","sequence":"additional","affiliation":[{"name":"Department of Microbiology, National Center of Infectious and Parasitic Diseases, 1504 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Evgenia","family":"Taseva","sequence":"additional","affiliation":[{"name":"Department of Microbiology, National Center of Infectious and Parasitic Diseases, 1504 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elitsa","family":"Panayotova","sequence":"additional","affiliation":[{"name":"Department of Microbiology, National Center of Infectious and Parasitic Diseases, 1504 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Iva","family":"Vladimirova","sequence":"additional","affiliation":[{"name":"Department of Microbiology, National Center of Infectious and Parasitic Diseases, 1504 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vladislava","family":"Ivanova","sequence":"additional","affiliation":[{"name":"Department of Microbiology, National Center of Infectious and Parasitic Diseases, 1504 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eleonora","family":"Kuteva","sequence":"additional","affiliation":[{"name":"Department of Microbiology, National Center of Infectious and Parasitic Diseases, 1504 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7878-3995","authenticated-orcid":false,"given":"Iva","family":"Christova","sequence":"additional","affiliation":[{"name":"Department of Microbiology, National Center of Infectious and Parasitic Diseases, 1504 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,9,2]]},"reference":[{"key":"ref_1","unstructured":"European Centre for Disease Prevention and Control (2024, August 26). 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