{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T23:38:12Z","timestamp":1785368292492,"version":"3.55.0"},"reference-count":52,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2016,8,18]],"date-time":"2016-08-18T00:00:00Z","timestamp":1471478400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002341","name":"Suomen Akatemia","doi-asserted-by":"publisher","award":["1285976"],"award-info":[{"award-number":["1285976"]}],"id":[{"id":"10.13039\/501100002341","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100008376","name":"Helsingin ja Uudenmaan Sairaanhoitopiiri","doi-asserted-by":"publisher","award":["2013405"],"award-info":[{"award-number":["2013405"]}],"id":[{"id":"10.13039\/100008376","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100008376","name":"Helsingin ja Uudenmaan Sairaanhoitopiiri","doi-asserted-by":"publisher","award":["2015318"],"award-info":[{"award-number":["2015318"]}],"id":[{"id":"10.13039\/100008376","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003502","name":"Ella ja Georg Ehrnroothin S\u00e4\u00e4ti\u00f6","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100003502","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.mdpi.com"],"crossmark-restriction":true},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Ticks carry several human pathogenic microbes including Borreliae and Flavivirus causing tick-born encephalitis. Ticks can also carry DNA of Chlamydia-like organisms (CLOs). The purpose of this study was to investigate the occurrence of CLOs in ticks and skin biopsies taken from individuals with suspected tick bite. DNA from CLOs was detected by pan-Chlamydiales-PCR in 40% of adult ticks from southwestern Finland. The estimated minimal infection rate for nymphs and larvae (studied in pools) was 6% and 2%, respectively. For the first time, we show CLO DNA also in human skin as 68% of all skin biopsies studied contained CLO DNA as determined through pan-Chlamydiales-PCR. Sequence analyses based on the 16S rRNA gene fragment indicated that the sequences detected in ticks were heterogeneous, representing various CLO families; whereas the majority of the sequences from human skin remained \u201cunclassified Chlamydiales\u201d and might represent a new family-level lineage. CLO sequences detected in four skin biopsies were most closely related to \u201cuncultured Chlamydial bacterium clones from Ixodes ricinus ticks\u201d and two of them were very similar to CLO sequences from Finnish ticks. These results suggest that CLO DNA is present in human skin; ticks carry CLOs and could potentially transmit CLOs to humans.<\/jats:p>","DOI":"10.3390\/microorganisms4030028","type":"journal-article","created":{"date-parts":[[2016,8,18]],"date-time":"2016-08-18T09:58:54Z","timestamp":1471514334000},"page":"28","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["Chlamydia-Like Organisms (CLOs) in Finnish Ixodes ricinus Ticks and Human Skin"],"prefix":"10.3390","volume":"4","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4428-7536","authenticated-orcid":false,"given":"Kati","family":"Hokynar","sequence":"first","affiliation":[{"name":"Department of Virology, Hartman institute, University of Helsinki, Helsinki 00014, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6763-8477","authenticated-orcid":false,"given":"Jani","family":"Sormunen","sequence":"additional","affiliation":[{"name":"Department of Biology, University of Turku, Turku 20014, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3665-5802","authenticated-orcid":false,"given":"Eero","family":"Vesterinen","sequence":"additional","affiliation":[{"name":"Department of Biology, University of Turku, Turku 20014, Finland"},{"name":"Department of Agricultural Sciences, University of Helsinki, Helsinki 00014, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Esa","family":"Partio","sequence":"additional","affiliation":[{"name":"Medical Center S\u00f6der, S\u00f6derkulla 01150, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas","family":"Lilley","sequence":"additional","affiliation":[{"name":"Biology Department, Bucknell University, Lewisburg, PA 17837, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Veera","family":"Timonen","sequence":"additional","affiliation":[{"name":"Department of Virology, Hartman institute, University of Helsinki, Helsinki 00014, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jaana","family":"Panelius","sequence":"additional","affiliation":[{"name":"Department of Dermatology and Allergology, University of Helsinki and Helsinki University Central Hospital, Helsinki 00250, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4335-0396","authenticated-orcid":false,"given":"Annamari","family":"Ranki","sequence":"additional","affiliation":[{"name":"Department of Dermatology and Allergology, University of Helsinki and Helsinki University Central Hospital, Helsinki 00250, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7413-6793","authenticated-orcid":false,"given":"Mirja","family":"Puolakkainen","sequence":"additional","affiliation":[{"name":"Department of Virology, Hartman institute, University of Helsinki, Helsinki 00014, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2016,8,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"415","DOI":"10.1099\/00207713-49-2-415","article-title":"Emended description of the order Chlamydiales, proposal of Parachlamydiaceae fam. nov. and simkaniaceae fam. nov., each containing one monotypic genus, revised taxonomy of the family Chlamydiaceae, including a new genus and five new species, and standards for the identification of organisms","volume":"49","author":"Everett","year":"1999","journal-title":"Int. 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