Efficacy of a novel SARS-CoV-2 detection kit without RNA extraction and purification

Fukumoto, T.; Iwasaki, S.; Hayasaka, K.; Sato, K.; Oguri, S.; Taki, K.; Nakakubo, S.; Kamada, K.; Yamashita, Y.; Konno, S.; Nishida, M.; Sugita, J.; Teshima, T.

doi:10.1101/2020.05.27.120410

bioRxiv · 10.1101/2020.05.27.120410

Efficacy of a novel SARS-CoV-2 detection kit without RNA extraction and purification

Fukumoto, T.·Iwasaki, S.·Hayasaka, K.·Sato, K.·Oguri, S.·Taki, K.·Nakakubo, S.·Kamada, K.·Yamashita, Y.·Konno, S.·Nishida, M.·Sugita, J.·Teshima, T.

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Abstract

Rapid detection of SARS-CoV-2 is critical for the diagnosis of coronavirus disease 2019 (COVID-19) and preventing the spread of the virus. A novel "2019 Novel Coronavirus Detection Kit (nCoV-DK)" halves detection time by eliminating the steps of RNA extraction and purification. We evaluated concordance between the nCoV-DK and direct PCR. The virus was detected in 53/71 fresh samples by the direct method and 55/71 corresponding frozen samples by the nCoV-DK. The overall concordance rate of the virus detection between the two methods was 94.4% (95% CI, 86.2-98.4). Concordance rates were 95.2% (95% CI, 83.8-99.4), 95.5% (95% CI, 77.2-99.9), 85.7% (95% CI, 42.1-99.6) in nasopharyngeal swab, saliva, and sputum samples, respectively. These results indicate that the nCoV-DK effectively detects SARS-CoV-2 in all types of the samples including saliva, while reducing time required for detection, labor, and risk of human error.

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Fukumoto, T., Iwasaki, S., Hayasaka, K., Sato, K., Oguri, S., Taki, K., Nakakubo, S., Kamada, K., Yamashita, Y., Konno, S., Nishida, M., Sugita, J., Teshima, T.. 2020-05-29. Efficacy of a novel SARS-CoV-2 detection kit without RNA extraction and purification. https://doi.org/10.1101/2020.05.27.120410

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