{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,6]],"date-time":"2026-07-06T18:57:31Z","timestamp":1783364251548,"version":"3.54.6"},"reference-count":51,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2024,7,27]],"date-time":"2024-07-27T00:00:00Z","timestamp":1722038400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Junta de Castilla y Le\u00f3n, Consejer\u00eda de Sanidad"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Insects"],"abstract":"<jats:p>Tick-borne rickettsioses (TBRs) are distributed worldwide and are recognized as important emerging vector-borne zoonotic diseases in Europe. The aim of this study was to identify tick-associated Rickettsia among ticks removed from humans, and to track how tick populations and their associated pathogens have changed over the years. For this purpose, we conducted a tick surveillance study in northwestern Spain between 2018 and 2022. Ticks were morphologically identified and analyzed for the presence of rickettsial pathogens through the amplification of the citrate synthase (gltA) and the outer membrane protein A (ompA) genes. PCR products were sequenced and subjected to phylogenetic analyses. We collected 7397 ticks, with Ixodes ricinus being the species most frequently isolated. Based on the PCR results, Rickettsia DNA was detected in 1177 (15.91%) ticks, and 10 members of Rickettsia were identified: R. aeschlimannii, R. conorii subsp. conorii, R. conorii subsp. raoultii, R. massiliae, R. monacensis, R. sibirica subsp. mongolitimonae, R. slovaca, R. helvetica, Candidatus R. barbariae, and Candidatus R. rioja. Some of these Rickettsia have gone previously undetected in the study region. There is clear geographic and seasonal expansion not only of tick populations, but also of the associated Rickettsia. The comparison of our data with those obtained years ago provides a clear idea of how the spatiotemporal distributions of ticks and their associated Rickettsiae have changed over the years.<\/jats:p>","DOI":"10.3390\/insects15080571","type":"journal-article","created":{"date-parts":[[2024,7,29]],"date-time":"2024-07-29T12:27:43Z","timestamp":1722256063000},"page":"571","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Identification of Rickettsia spp. in Ticks Removed from Tick-Bitten Humans in Northwestern Spain"],"prefix":"10.3390","volume":"15","author":[{"given":"Mar\u00eda Carmen","family":"Vieira Lista","sequence":"first","affiliation":[{"name":"Infectious and Tropical Diseases Research Group (e-INTRO), Biomedical Research Institute of Salamanca-Research Centre for Tropical Diseases (IBSAL-CIETUS), Faculty of Pharmacy, University of Salamanca, 37008 Salamanca, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mar\u00eda Bel\u00e9n","family":"Vicente Santiago","sequence":"additional","affiliation":[{"name":"Infectious and Tropical Diseases Research Group (e-INTRO), Biomedical Research Institute of Salamanca-Research Centre for Tropical Diseases (IBSAL-CIETUS), Faculty of Pharmacy, University of Salamanca, 37008 Salamanca, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2237-9691","authenticated-orcid":false,"given":"Julio David","family":"Soto-L\u00f3pez","sequence":"additional","affiliation":[{"name":"Infectious and Tropical Diseases Research Group (e-INTRO), Biomedical Research Institute of Salamanca-Research Centre for Tropical Diseases (IBSAL-CIETUS), Faculty of Pharmacy, University of Salamanca, 37008 Salamanca, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joaquina Mar\u00eda","family":"Garc\u00eda-Mart\u00edn","sequence":"additional","affiliation":[{"name":"Infectious and Tropical Diseases Research Group (e-INTRO), Biomedical Research Institute of Salamanca-Research Centre for Tropical Diseases (IBSAL-CIETUS), Faculty of Pharmacy, University of Salamanca, 37008 Salamanca, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rufino","family":"\u00c1lamo-Sanz","sequence":"additional","affiliation":[{"name":"Consejer\u00eda de Sanidad Junta Castilla y Le\u00f3n, 47007 Valladolid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2230-1256","authenticated-orcid":false,"given":"Moncef","family":"Belhassen-Garc\u00eda","sequence":"additional","affiliation":[{"name":"Infectious and Tropical Diseases Research Group (e-INTRO), Biomedical Research Institute of Salamanca-Research Centre for Tropical Diseases (IBSAL-CIETUS), Faculty of Pharmacy, University of Salamanca, 37008 Salamanca, Spain"},{"name":"Infectious Diseases Unit, Department of Internal Medicine, University Hospital of Salamanca, 37008 Salamanca, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0244-4740","authenticated-orcid":false,"given":"Antonio","family":"Muro","sequence":"additional","affiliation":[{"name":"Infectious and Tropical Diseases Research Group (e-INTRO), Biomedical Research Institute of Salamanca-Research Centre for Tropical Diseases (IBSAL-CIETUS), Faculty of Pharmacy, University of Salamanca, 37008 Salamanca, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,7,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"271","DOI":"10.1016\/j.ttbdis.2012.10.035","article-title":"Tick-borne rickettsioses in Europe","volume":"3","author":"Oteo","year":"2012","journal-title":"Ticks Tick Borne Dis."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"132","DOI":"10.1016\/j.ttbdis.2018.09.006","article-title":"Tick species diversity and population dynamics of Ixodes ricinus in Galicia (north-western Spain)","volume":"10","author":"Remesar","year":"2019","journal-title":"Ticks Tick Borne Dis."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"834","DOI":"10.1016\/j.micinf.2015.09.009","article-title":"Rickettsioses in Europe","volume":"17","author":"Portillo","year":"2015","journal-title":"Microbes Infect."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Guccione, C., Colomba, C., Tolomeo, M., Trizzino, M., Iaria, C., and Cascio, A. 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