{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T22:04:58Z","timestamp":1790805898677,"version":"4.1.0"},"reference-count":30,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2022,10,31]],"date-time":"2022-10-31T00:00:00Z","timestamp":1667174400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Oslo University Hospital","award":["312780"],"award-info":[{"award-number":["312780"]}]},{"DOI":"10.13039\/501100005416","name":"Research Council of Norway","doi-asserted-by":"publisher","award":["312780"],"award-info":[{"award-number":["312780"]}],"id":[{"id":"10.13039\/501100005416","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Vivaldi Invest A\/S","award":["312780"],"award-info":[{"award-number":["312780"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>The Omicron variant of SARS-CoV-2 spreads more easily than earlier variants, possibly as a result of a higher viral load in the upper respiratory tract and oral cavity. Hence, we investigated whether the Omicron variant generates a higher viral load than that of the Delta variant in saliva and nasopharynx. Both specimens were collected from 52 Omicron and 17 Delta cases at two time points one week apart and analyzed by qRT-PCR. Viral load was measured as 10 log RNA genome copies per 1000 human cells according to the WHO reference standard. We found that Omicron cases carried a higher viral load and had more sustained viral shedding compared to the Delta cases, especially in the nasopharynx.<\/jats:p>","DOI":"10.3390\/v14112420","type":"journal-article","created":{"date-parts":[[2022,11,2]],"date-time":"2022-11-02T03:44:17Z","timestamp":1667360657000},"page":"2420","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Omicron Variant Generates a Higher and More Sustained Viral Load in Nasopharynx and Saliva Than the Delta Variant of SARS-CoV-2"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6951-2317","authenticated-orcid":false,"given":"Beathe K.","family":"Granerud","sequence":"first","affiliation":[{"name":"Institute of Clinical Medicine, University of Oslo, 0316 Oslo, Norway"},{"name":"Department of Microbiology, Oslo University Hospital, 0424 Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thor","family":"Ueland","sequence":"additional","affiliation":[{"name":"Institute of Clinical Medicine, University of Oslo, 0316 Oslo, Norway"},{"name":"Research Institute of Internal Medicine, Oslo University Hospital, 0424 Oslo, Norway"},{"name":"K.G. Jebsen Thrombosis Research and Expertise Center, Faculty of Health Sciences, University of Troms\u00f8, 6050 Troms\u00f8, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andreas","family":"Lind","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Oslo University Hospital, 0424 Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arne","family":"S\u00f8raas","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Oslo University Hospital, 0424 Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6828-0609","authenticated-orcid":false,"given":"B\u00f8rre","family":"Fevang","sequence":"additional","affiliation":[{"name":"Research Institute of Internal Medicine, Oslo University Hospital, 0424 Oslo, Norway"},{"name":"Section of Clinical Immunology and Infectious Diseases, Oslo University Hospital, 0424 Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anne Katrine","family":"Steffensen","sequence":"additional","affiliation":[{"name":"Institute of Clinical Medicine, University of Oslo, 0316 Oslo, Norway"},{"name":"Department of Microbiology, Oslo University Hospital, 0424 Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Huda","family":"Al-Baldawi","sequence":"additional","affiliation":[{"name":"Institute of Clinical Medicine, University of Oslo, 0316 Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fridtjof","family":"Lund-Johansen","sequence":"additional","affiliation":[{"name":"Department of Immunology, Oslo University Hospital, 0424 Oslo, Norway"},{"name":"ImmunoLingo Convergence Centre, University of Oslo, 0316 Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"P\u00e5l","family":"Aukrust","sequence":"additional","affiliation":[{"name":"Institute of Clinical Medicine, University of Oslo, 0316 Oslo, Norway"},{"name":"Research Institute of Internal Medicine, Oslo University Hospital, 0424 Oslo, Norway"},{"name":"K.G. Jebsen Thrombosis Research and Expertise Center, Faculty of Health Sciences, University of Troms\u00f8, 6050 Troms\u00f8, Norway"},{"name":"Section of Clinical Immunology and Infectious Diseases, Oslo University Hospital, 0424 Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bente","family":"Halvorsen","sequence":"additional","affiliation":[{"name":"Institute of Clinical Medicine, University of Oslo, 0316 Oslo, Norway"},{"name":"Research Institute of Internal Medicine, Oslo University Hospital, 0424 Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tuva B.","family":"Dahl","sequence":"additional","affiliation":[{"name":"Research Institute of Internal Medicine, Oslo University Hospital, 0424 Oslo, Norway"},{"name":"Division of Critical Care and Emergencies, Oslo University Hospital, 0424 Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5047-4982","authenticated-orcid":false,"given":"Susanne","family":"Dudman","sequence":"additional","affiliation":[{"name":"Institute of Clinical Medicine, University of Oslo, 0316 Oslo, Norway"},{"name":"Department of Microbiology, Oslo University Hospital, 0424 Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fredrik","family":"M\u00fcller","sequence":"additional","affiliation":[{"name":"Institute of Clinical Medicine, University of Oslo, 0316 Oslo, Norway"},{"name":"Department of Microbiology, Oslo University Hospital, 0424 Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1618-5022","authenticated-orcid":false,"given":"Jan Cato","family":"Holter","sequence":"additional","affiliation":[{"name":"Institute of Clinical Medicine, University of Oslo, 0316 Oslo, Norway"},{"name":"Department of Microbiology, Oslo University Hospital, 0424 Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,10,31]]},"reference":[{"key":"ref_1","unstructured":"World Health Organization (2022, October 26). 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