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Under isothermal conditions at 65\u00a0\u00b0C, the entire procedure takes approximately 30\u00a0min to complete. In this study, we establish a sensitive and visualized LAMP method in a closed-tube system for the detection of<jats:italic>Plasmodium knowlesi<\/jats:italic>.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>A total of 71 malaria microscopy positive blood samples collected in blood spots were obtained from the Sarawak State Health Department. Using<jats:italic>18s rRNA<\/jats:italic>as the target gene, nested PCR and SYBR green I LAMP assay were performed following the DNA extraction. The colour changes of LAMP end products were observed by naked eyes.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>LAMP assay demonstrated a detection limit of 10 copies\/\u00b5L in comparison with 100 copies\/\u00b5L nested PCR. Of 71<jats:italic>P. knowlesi<\/jats:italic>blood samples collected, LAMP detected 69 microscopy-positive samples. LAMP exhibited higher sensitivity than nested PCR assay. The SYBR green I LAMP assay was 97.1% sensitive (95% CI 90.2\u201399.7%) and 100% specific (95% CI 83.2\u2013100%). Without opening the cap, incorporation of SYBR green I into the inner cap of the tube enabled the direct visualization of results upon completion of amplification. The positives instantaneously turned green while the negatives remained orange.<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusions<\/jats:title><jats:p>These results indicate that SYBR green I LAMP assay is a convenient diagnosis tool for the detection of<jats:italic>P. knowlesi<\/jats:italic>in remote settings.<\/jats:p><\/jats:sec>","DOI":"10.1186\/s12936-021-03707-0","type":"journal-article","created":{"date-parts":[[2021,3,25]],"date-time":"2021-03-25T21:02:54Z","timestamp":1616706174000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":33,"title":["Validation of SYBR green I based closed\u2010tube loop\u2010mediated isothermal amplification (LAMP) assay for diagnosis of knowlesi malaria"],"prefix":"10.1186","volume":"20","author":[{"given":"Meng Yee","family":"Lai","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Choo Huck","family":"Ooi","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2037-2165","authenticated-orcid":false,"given":"Yee Ling","family":"Lau","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2021,3,25]]},"reference":[{"key":"3707_CR1","first-page":"166","volume":"65","author":"B Singh","year":"2018","unstructured":"Singh B, Daneshvar C. 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No. 817.1).","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and consent to participate"}},{"value":"Not applicable.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"MYL, CHO and YLL have no competing interests.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"166"}}