{"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":1790790829689,"version":"4.1.0"},"reference-count":25,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2020,7,29]],"date-time":"2020-07-29T00:00:00Z","timestamp":1595980800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"The University Grant Committee","award":["T11-707\/15-R"],"award-info":[{"award-number":["T11-707\/15-R"]}]},{"name":"The University Development Fund of the University of Hong Kong","award":["N\/A"],"award-info":[{"award-number":["N\/A"]}]},{"name":"Hong Kong Government Consultancy Service","award":["N\/A"],"award-info":[{"award-number":["N\/A"]}]},{"name":"Innovation and Technology Fund and Health and Medical Research Fund","award":["N\/A"],"award-info":[{"award-number":["N\/A"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>To control the COVID-19 pandemic and prevent its resurgence in areas preparing for a return of economic activities, a method for a rapid, simple, and inexpensive point-of-care diagnosis and mass screening is urgently needed. We developed and evaluated a one-step colorimetric reverse-transcriptional loop-mediated isothermal amplification assay (COVID-19-LAMP) for detection of SARS-CoV-2, using SARS-CoV-2 isolate and respiratory samples from patients with COVID-19 (n = 223) and other respiratory virus infections (n = 143). The assay involves simple equipment and techniques and low cost, without the need for expensive qPCR machines, and the result, indicated by color change, is easily interpreted by naked eyes. COVID-19-LAMP can detect SARS-CoV-2 RNA with detection limit of 42 copies\/reaction. Of 223 respiratory samples positive for SARS-CoV-2 by qRT-PCR, 212 and 219 were positive by COVID-19-LAMP at 60 and 90 min (sensitivities of 95.07% and 98.21%) respectively, with the highest sensitivities among nasopharyngeal swabs (96.88% and 98.96%), compared to sputum\/deep throat saliva samples (94.03% and 97.02%), and throat swab samples (93.33% and 98.33%). None of the 143 samples with other respiratory viruses were positive by COVID-19-LAMP, showing 100% specificity. Samples with higher viral load showed shorter detection time, some as early as 30 min. This inexpensive, highly sensitive and specific COVID-19-LAMP assay can be useful for rapid deployment as mobile diagnostic units to resource-limiting areas for point-of-care diagnosis, and for unlimited high-throughput mass screening at borders to reduce cross-regional transmission.<\/jats:p>","DOI":"10.3390\/ijms21155380","type":"journal-article","created":{"date-parts":[[2020,7,29]],"date-time":"2020-07-29T07:31:45Z","timestamp":1596007905000},"page":"5380","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":94,"title":["A Rapid, Simple, Inexpensive, and Mobile Colorimetric Assay COVID-19-LAMP for Mass On-Site Screening of COVID-19"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1275-2464","authenticated-orcid":false,"given":"Franklin","family":"Chow","sequence":"first","affiliation":[{"name":"Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong 19\/F, Block T, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tony","family":"Chan","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong 19\/F, Block T, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anthony","family":"Tam","sequence":"additional","affiliation":[{"name":"Department of Medicine, Queen Mary Hospital, Hong Kong 102 Pok Fu Lam Road, Pok Fu Lam, Hong Kong Island, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Suhui","family":"Zhao","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong 19\/F, Block T, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Weiming","family":"Yao","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong 19\/F, Block T, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joshua","family":"Fung","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong 19\/F, Block T, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Flora","family":"Cheng","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong 19\/F, Block T, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9325-4322","authenticated-orcid":false,"given":"George","family":"Lo","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong 19\/F, Block T, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stella","family":"Chu","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong 19\/F, Block T, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kam","family":"Aw-Yong","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong 19\/F, Block T, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"James","family":"Tang","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong 19\/F, Block T, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6705-2866","authenticated-orcid":false,"given":"Chi-Ching","family":"Tsang","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong 19\/F, Block T, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hayes","family":"Luk","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong 19\/F, Block T, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5565-1121","authenticated-orcid":false,"given":"Antonio","family":"Wong","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong 19\/F, Block T, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8886-0563","authenticated-orcid":false,"given":"Kenneth","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong 19\/F, Block T, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Longchao","family":"Zhu","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong 19\/F, Block T, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zirong","family":"He","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong 19\/F, Block T, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emily","family":"Tam","sequence":"additional","affiliation":[{"name":"Department of Food and Health Sciences, Faculty of Science and Technology, Technological and Higher Education Institute of Hong Kong, Hong Kong Tsing Yi Road, Tsing Yi, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tom","family":"Chung","sequence":"additional","affiliation":[{"name":"Department of Microbiology, The University of Hong Kong, Queen Mary Hospital, Hong Kong Block T, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sally","family":"Wong","sequence":"additional","affiliation":[{"name":"Department of Pathology, Queen Elizabeth Hospital, Hong Kong 10\/F, Block M, Queen Elizabeth Hospital, 30 Gascoigne Road, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tak-Lun","family":"Que","sequence":"additional","affiliation":[{"name":"Department of Pathology, Tuen Mun Hospital, Hong Kong Pathology Block, 23 Tsing Chung Koon Road, Tuen Mun, New Territories, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kitty","family":"Fung","sequence":"additional","affiliation":[{"name":"Department of Pathology, United Christian Hospital, Hong Kong 130 Hip Wo Street, Kwun Tong, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6047-9744","authenticated-orcid":false,"given":"David","family":"Lung","sequence":"additional","affiliation":[{"name":"Department of Pathology, Queen Elizabeth Hospital, Hong Kong 10\/F, Block M, Queen Elizabeth Hospital, 30 Gascoigne Road, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alan","family":"Wu","sequence":"additional","affiliation":[{"name":"Department of Clinical Pathology, Pamela Youde Nethersole Eastern Hospital, Hong Kong 3 Lok Man Road, Chai Wan, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ivan","family":"Hung","sequence":"additional","affiliation":[{"name":"Department of Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong 4\/F, Professorial Block, Queen Mary Hospital, 102 Pok Fu Lam Road, Hong 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Diseases, The University of Hong Kong, Pokfulam, Hong Kong Laboratory Block, 21 Sassoon Road, Pokfulam and University Pathology Building, Queen Mary Hospital, The University of Hong Kong, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,7,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Coronaviridae Study Group of the International Committee on Taxonomy of Viruses (2020). 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