{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,8]],"date-time":"2025-12-08T08:41:15Z","timestamp":1765183275432,"version":"3.46.0"},"reference-count":39,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2025,12,4]],"date-time":"2025-12-04T00:00:00Z","timestamp":1764806400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Bulgarian Ministry of Education and Science"},{"name":"Trakia University","award":["BG-RRP-2.004-0006-C02"],"award-info":[{"award-number":["BG-RRP-2.004-0006-C02"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>The tick species Ixodes ricinus is the most widely distributed throughout Europe and serves as the primary vector for the spirochete Borrelia burgdorferi sensu lato (s.l.), which is responsible for Lyme borreliosis. The present study evaluated the prevalence of B. burgdorferi (s.l.) in I. ricinus ticks using nPCR amplification. Ticks were collected from three geographical regions in Bulgaria: the Black Sea Coast in the east, the Pleven region in the north, and the Stara Zagora region in the central south. This study focused on urban and peri-urban areas, including heavily traveled trails in parks. The results indicated statistically significant differences in infection rates, with the highest percentage of infected ticks found in Pleven (52.34%), followed by Stara Zagora (35.46%) and the lowest on the Black Sea Coast (23.08%). Furthermore, we conducted genospecies molecular identification of B. afzelii and B. garinii by PCR amplification of genospecies-specific nucleotide sequences in the 16S rRNA gene. The lowest prevalence of B. afzelii was recorded in Stara Zagora at 10.64%, followed by the Black Sea region at 12.5%, while the statistically highest frequency was observed in Pleven at 21.03%. The prevalence of B. garinii among the total number of I. ricinus ticks was greatest in Pleven at 15.89%, followed by the Black Sea region at 8.65%, and the lowest in the Stara Zagora region at 4.96%. Statistically significant differences were found only between Pleven and Stara Zagora (p = 0.002), but no significant differences in infection rates were observed between adults and nymphs in the regions examined. Overall, the prevalence of B. afzelii in each region exceeds that of B. garinii, and when considered collectively for Bulgaria, the frequency of B. afzelii (15.9%) is higher than that of B. garinii (10.89%) in infected ticks. In a controlled epidemiological context, managing the population of I. ricinus infected with B. burgdorferi s.l. can mitigate the health burden of Lyme disease, although this preventive strategy may not guarantee complete protection.<\/jats:p>","DOI":"10.3390\/pathogens14121240","type":"journal-article","created":{"date-parts":[[2025,12,4]],"date-time":"2025-12-04T15:14:06Z","timestamp":1764861246000},"page":"1240","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Prevalence of Borrelia afzelii and Borrelia garinii Genospecies in Ixodes ricinus Ticks Collected from Three Regions in Bulgaria"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5915-2883","authenticated-orcid":false,"given":"Iskren","family":"Stanilov","sequence":"first","affiliation":[{"name":"Department of Hygiene, Epidemiology, Microbiology, Parasitology and Infectious Diseases, Medical Faculty, Trakia University, 6000 Stara Zagora, Bulgaria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0092-9488","authenticated-orcid":false,"given":"Alexander","family":"Blazhev","sequence":"additional","affiliation":[{"name":"Department of Biology, Medical University\u2014Pleven, 5800 Pleven, Bulgaria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-6411-9357","authenticated-orcid":false,"given":"Borislava","family":"Chakarova","sequence":"additional","affiliation":[{"name":"Department of Hygiene, Epidemiology, Microbiology, Parasitology and Infectious Diseases, Medical Faculty, Trakia University, 6000 Stara Zagora, Bulgaria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1368-9081","authenticated-orcid":false,"given":"Spaska","family":"Stanilova","sequence":"additional","affiliation":[{"name":"Department of Molecular Biology, Immunology and Medical Genetics, Medical Faculty, Trakia University, 6000 Stara Zagora, Bulgaria"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e00609-17","DOI":"10.1128\/AEM.00609-17","article-title":"Europe-wide meta-analysis of Borrelia burgdorferi sensu lato prevalence in questing Ixodes ricinus ticks","volume":"83","author":"Strnad","year":"2017","journal-title":"Appl. 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