{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,13]],"date-time":"2026-09-13T02:40:58Z","timestamp":1789267258792,"version":"build-2803163510"},"reference-count":26,"publisher":"Public Library of Science (PLoS)","issue":"7","license":[{"start":{"date-parts":[[2025,7,11]],"date-time":"2025-07-11T00:00:00Z","timestamp":1752192000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012284","name":"Chica and Heinz Schaller Foundation","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100012284","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002347","name":"Bundesministerium f\u00fcr Bildung und Forschung","doi-asserted-by":"publisher","award":["01KX2021"],"award-info":[{"award-number":["01KX2021"]}],"id":[{"id":"10.13039\/501100002347","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002347","name":"Bundesministerium f\u00fcr Bildung und Forschung","doi-asserted-by":"publisher","award":["01KX2021"],"award-info":[{"award-number":["01KX2021"]}],"id":[{"id":"10.13039\/501100002347","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003542","name":"Ministerium f\u00fcr Wissenschaft, Forschung und Kunst Baden-W\u00fcrttemberg","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100003542","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002347","name":"Bundesministerium f\u00fcr Bildung und Forschung","doi-asserted-by":"publisher","award":["01KX2021"],"award-info":[{"award-number":["01KX2021"]}],"id":[{"id":"10.13039\/501100002347","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:sec id=\"sec021\">\n<jats:title>Background<\/jats:title>\n<jats:p>Serology is a valuable tool to estimate infections, case-fatality rates, and immunity. However, venipuncture and clinical infrastructure hinder scalability. This study evaluated the performance, feasibility and user experience of using a microsampling device for self-collected capillary blood and saliva to determine total SARS-CoV-2 S RBD antibodies.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec022\">\n<jats:title>Methods<\/jats:title>\n<jats:p>It included 149 participants with (n\u2009=\u200948) or without (n\u2009=\u2009101) a known history of SARS-CoV-2 infection and confirmed antibodies. Venous and capillary blood were self- or professionally collected from all, and saliva was self-collected by 46\/48 participants with antibodies. The detection of SARS-CoV-2 S RBD antibodies in all sample types was tested using a high-throughput platform and agreement was calculated. Intra- and inter-rater agreement between serum and capillary blood in participants with an unknown antibody status was also assessed. Participants evaluated the device\u2019s user-friendliness through questionnaires.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec023\">\n<jats:title>Results<\/jats:title>\n<jats:p>Among the 48 participants with known past infection and antibodies, agreement was 100% (95% CI: 92.6\u2013100) between serum and capillary blood (self-collected or professionally collected). Self-collected saliva had slightly lower agreement with paired serum samples (95.7%, CI: 85.2\u201399.5). For the 101 participants without prior evidence of antibodies or infection, serum and self-collected capillary blood had good intra-rater agreement and serum and professionally collected capillary blood had almost perfect intra-rater agreement. Inter-rater agreement was also almost perfect. While 81.8% found the self-finger prick easy, 53.4% found using the microsampler easy. Among those who collected saliva, 84.8% found capillary blood easier to collect compared to saliva (52.2%).<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec024\">\n<jats:title>Conclusions<\/jats:title>\n<jats:p>Our results show that detecting SARS-CoV-2 antibodies from capillary blood and saliva collected with the VAMS microsampling device is feasible and yields valid results. To ensure accuracy and reliability, additional training in self-sampling techniques may be essential. The positive user experience further underscores the microsampling device\u2019s potential for scalable serosurveillance and strengthening pandemic preparedness efforts.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pone.0327821","type":"journal-article","created":{"date-parts":[[2025,7,11]],"date-time":"2025-07-11T17:35:03Z","timestamp":1752255303000},"page":"e0327821","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":1,"title":["Performance and feasibility of self-microsampling of capillary blood and saliva for serological testing of SARS-CoV-2"],"prefix":"10.1371","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6803-9284","authenticated-orcid":true,"given":"Ivonne","family":"Morales","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Josh","family":"Bueggeln","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna","family":"Denzler","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vera","family":"Sonntag-Buck","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kathleen","family":"B\u00f6rner","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Petr","family":"Chlanda","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lisa","family":"Koeppel","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andreas","family":"Deckert","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Till","family":"B\u00e4rnighausen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Knop","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7216-7067","authenticated-orcid":true,"given":"Claudia 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