{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T17:53:49Z","timestamp":1790790829653,"version":"4.1.0"},"reference-count":42,"publisher":"Public Library of Science (PLoS)","issue":"12","license":[{"start":{"date-parts":[[2020,12,31]],"date-time":"2020-12-31T00:00:00Z","timestamp":1609372800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"The Wisconsin Alumni Research Foundation COVID19 Challenge","award":["144 AAH9333"],"award-info":[{"award-number":["144 AAH9333"]}]},{"name":"Rapid Acceleration of Diagnostics, National Institutes of Health","award":["144 AAl2136"],"award-info":[{"award-number":["144 AAl2136"]}]},{"DOI":"10.13039\/100000052","name":"NIH Office of the Director","doi-asserted-by":"publisher","award":["P51OD011106"],"award-info":[{"award-number":["P51OD011106"]}],"id":[{"id":"10.13039\/100000052","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:p>SARS-CoV-2 testing is crucial to controlling the spread of this virus, yet shortages of nucleic acid extraction supplies and other key reagents have hindered the response to COVID-19 in the US. Several groups have described loop-mediated isothermal amplification (LAMP) assays for SARS-CoV-2, including testing directly from nasopharyngeal swabs and eliminating the need for reagents in short supply. Frequent surveillance of individuals attending work or school is currently unavailable to most people but will likely be necessary to reduce the ~50% of transmission that occurs when individuals are nonsymptomatic. Here we describe a fluorescence-based RT-LAMP test using direct nasopharyngeal swab samples and show consistent detection in clinically confirmed primary samples with a limit of detection (LOD) of ~625 copies\/\u03bcl, approximately 100-fold lower sensitivity than qRT-PCR. While less sensitive than extraction-based molecular methods, RT-LAMP without RNA extraction is fast and inexpensive. Here we also demonstrate that adding a lysis buffer directly into the RT-LAMP reaction improves the sensitivity of some samples by approximately 10-fold. Furthermore, purified RNA in this assay achieves a similar LOD to qRT-PCR. These results indicate that high-throughput RT-LAMP testing could augment qRT-PCR in SARS-CoV-2 surveillance programs, especially while the availability of qRT-PCR testing and RNA extraction reagents is constrained.<\/jats:p>","DOI":"10.1371\/journal.pone.0244882","type":"journal-article","created":{"date-parts":[[2020,12,31]],"date-time":"2020-12-31T14:58:28Z","timestamp":1609426708000},"page":"e0244882","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":33,"title":["Optimizing direct RT-LAMP to detect transmissible SARS-CoV-2 from primary nasopharyngeal swab samples"],"prefix":"10.1371","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0934-2042","authenticated-orcid":true,"given":"Dawn M.","family":"Dudley","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christina M.","family":"Newman","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrea M.","family":"Weiler","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mitchell D.","family":"Ramuta","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cecilia G.","family":"Shortreed","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna S.","family":"Heffron","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Molly A.","family":"Accola","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"William M.","family":"Rehrauer","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas C.","family":"Friedrich","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David H.","family":"O\u2019Connor","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2020,12,31]]},"reference":[{"key":"pone.0244882.ref001","doi-asserted-by":"crossref","first-page":"2081","DOI":"10.1056\/NEJMoa2008457","article-title":"Presymptomatic SARS-CoV-2 Infections and Transmission in a Skilled Nursing Facility","volume":"382","author":"MM Arons","year":"2020","journal-title":"N Engl J Med"},{"key":"pone.0244882.ref002","doi-asserted-by":"crossref","first-page":"970","DOI":"10.1056\/NEJMc2001468","article-title":"Transmission of 2019-nCoV Infection from an Asymptomatic Contact in Germany","volume":"382","author":"C Rothe","year":"2020","journal-title":"N Engl J Med"},{"issue":"1","key":"pone.0244882.ref003","doi-asserted-by":"crossref","first-page":"e33","DOI":"10.1016\/j.jinf.2020.04.004","article-title":"CT imaging and clinical course of asymptomatic cases with COVID-19 pneumonia at admission in Wuhan, China","volume":"81","author":"H Meng","year":"2020","journal-title":"J Infect"},{"key":"pone.0244882.ref004","doi-asserted-by":"crossref","first-page":"425","DOI":"10.1038\/s41586-020-2488-1","article-title":"Suppression of a SARS-CoV-2 outbreak in the Italian municipality of Vo\u2019","volume":"584","author":"E Lavezzo","year":"2020","journal-title":"Nature"},{"issue":"12","key":"pone.0244882.ref005","doi-asserted-by":"crossref","first-page":"1177","DOI":"10.1056\/NEJMc2001737","article-title":"SARS-CoV-2 Viral Load in Upper Respiratory Specimens of Infected Patients","volume":"382","author":"L Zou","year":"2020","journal-title":"N Engl J Med"},{"issue":"11","key":"pone.0244882.ref006","first-page":"1","article-title":"Clinical Course and Molecular Viral Shedding Among Asymptomatic and Symptomatic Patients With SARS-CoV-2 Infection in a Community Treatment Center in the Republic of Korea","volume":"180","author":"S Lee","year":"2020","journal-title":"JAMA Internal Medicine"},{"key":"pone.0244882.ref007","unstructured":"Wu KJ. \u2018It\u2019s Like Groundhog Day\u2019: Coronavirus Testing Labs Again Lack Key Supplies. 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