{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T18:14:39Z","timestamp":1787681679073,"version":"build-2784847793"},"reference-count":30,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2020,6,19]],"date-time":"2020-06-19T00:00:00Z","timestamp":1592524800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100013276","name":"Interreg","doi-asserted-by":"publisher","award":["20200422"],"award-info":[{"award-number":["20200422"]}],"id":[{"id":"10.13039\/100013276","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biology"],"abstract":"<jats:p>Rickettsiosis is a vector-borne disease caused by bacterial species in the genus Rickettsia. Ticks in Scandinavia are reported to be infected with Rickettsia, yet only a few Scandinavian human cases are described, and rickettsiosis is poorly understood. The aim of this study was to determine the prevalence of rickettsiosis in Denmark based on laboratory findings. We found that in the Danish individuals who tested positive for Rickettsia by serology, the majority (86%; 484\/561) of the infections belonged to the spotted fever group. In contrast, we could confirm 13 of 41 (32%) PCR-positive individuals by sequencing and identified all of these as R. africae, indicating infections after travel exposure. These 13 samples were collected from wound\/skin material. In Denmark, approximately 85 individuals test positive for Rickettsia spp. annually, giving an estimated 26% (561\/2147) annual prevalence among those suspected of rickettsiosis after tick bites. However, without clinical data and a history of travel exposure, a true estimation of rickettsiosis acquired endemically by tick bites cannot be made. Therefore, we recommend that both clinical data and specific travel exposure be included in a surveillance system of Rickettsia infections.<\/jats:p>","DOI":"10.3390\/biology9060133","type":"journal-article","created":{"date-parts":[[2020,6,19]],"date-time":"2020-06-19T10:43:58Z","timestamp":1592563438000},"page":"133","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Laboratory Diagnostics of Rickettsia Infections in Denmark 2008\u20132015"],"prefix":"10.3390","volume":"9","author":[{"given":"Susanne","family":"Schj\u00f8rring","sequence":"first","affiliation":[{"name":"Department of Bacteria, Parasites and Fungi, Statens Serum Institut (SSI), 2300 Copenhagen, Denmark"},{"name":"European Program for Public Health Microbiology Training (EUPHEM), European Centre for Disease Prevention and Control (ECDC), 27180 Solnar, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martin Tugwell","family":"Jepsen","sequence":"additional","affiliation":[{"name":"Department of Bacteria, Parasites and Fungi, Statens Serum Institut (SSI), 2300 Copenhagen, Denmark"},{"name":"Scandtick Innovation, Project Group, InterReg, 551 11 J\u00f6nk\u00f6ping, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Camilla Adler","family":"S\u00f8rensen","sequence":"additional","affiliation":[{"name":"Scandtick Innovation, Project Group, InterReg, 551 11 J\u00f6nk\u00f6ping, Sweden"},{"name":"Virus and Microbiological Special Diagnostics, Statens Serum Institut (SSI), 2300 Copenhagen, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Palle","family":"Valentiner-Branth","sequence":"additional","affiliation":[{"name":"Department of Infectious Disease Epidemiology and Prevention, Statens Serum Institut (SSI), 2300 Copenhagen, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bj\u00f8rn","family":"Kants\u00f8","sequence":"additional","affiliation":[{"name":"Virus and Microbiological Special Diagnostics, Statens Serum Institut (SSI), 2300 Copenhagen, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1678-6605","authenticated-orcid":false,"given":"Randi F\u00f8ns","family":"Petersen","sequence":"additional","affiliation":[{"name":"Department of Bacteria, Parasites and Fungi, Statens Serum Institut (SSI), 2300 Copenhagen, Denmark"},{"name":"Virus and Microbiological Special Diagnostics, Statens Serum Institut (SSI), 2300 Copenhagen, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4860-1847","authenticated-orcid":false,"given":"Ole","family":"Skovgaard","sequence":"additional","affiliation":[{"name":"Department of Science and Environment, Roskilde University, 4000 Roskilde, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karen A.","family":"Krogfelt","sequence":"additional","affiliation":[{"name":"Department of Bacteria, Parasites and Fungi, Statens Serum Institut (SSI), 2300 Copenhagen, Denmark"},{"name":"Scandtick Innovation, Project Group, InterReg, 551 11 J\u00f6nk\u00f6ping, Sweden"},{"name":"Virus and Microbiological Special Diagnostics, Statens Serum Institut (SSI), 2300 Copenhagen, Denmark"},{"name":"Department of Science and Environment, Roskilde University, 4000 Roskilde, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,6,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"26","DOI":"10.4269\/ajtmh.15-0472","article-title":"National surveillance of spotted fever group rickettsioses in the United States, 2008\u20132012","volume":"94","author":"Drexler","year":"2016","journal-title":"Am. 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