Detection of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in clinical samples using Real-Time Reverse Transcription Polymerase Chain Reaction (qRT-PCR)

Abstract Background Pandemic coronavirus disease 2019 (COVID-19) disease represents a challenge for healthcare structures. The molecular confirmation of samples from infected individuals is crucial and therefore guides public health decision making. Clusters and possibly increased diffuse transmission could occur in the context of the next influenza season. For this reason, a diagnostic test able to discriminate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from influenza viruses is urgently needed. Methods A multiplex real-time reverse-transcription polymerase chain reaction (PCR) assay was assessed using 1 laboratory protocol with different real-time PCR instruments. Overall, 1000 clinical samples (600 from samples SARS-CoV-2–infected patients, 200 samples from influenza-infected patients, and 200 negative samples) were analyzed. Results The assay developed was able to detect and discriminate each virus target and to intercept coinfections. The limit of quantification of each assay ranged between 5 and 10 genomic copy numbers, with a cutoff value of 37.7 and 37.8 for influenza and SARS-CoV-2 viruses, respectively. Only 2 influenza coinfections were detected in COVID-19 samples. Conclusions This study suggests that multiplex assay is a rapid, valid, and accurate method for the detection of SARS-CoV-2 and influenza viruses in clinical samples. The test may be an important diagnostic tool for both diagnostic and surveillance purposes during the seasonal influenza activity period.

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Analysis and validation of a highly sensitive one-step nested quantitative real-time polymerase chain reaction assay for specific detection of severe acute respiratory syndrome coronavirus 2

Virology Journal ◽

10.1186/s12985-020-01467-y ◽

2020 ◽

Vol 17 (1) ◽

Author(s):

Yang Zhang ◽

Chunyang Dai ◽

Huiyan Wang ◽

Yong Gao ◽

Tuantuan Li ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Real Time ◽

Quantitative Polymerase Chain Reaction ◽

Clinical Samples ◽

Chain Reaction ◽

Pcr Assay ◽

Qrt Pcr ◽

Highly Sensitive ◽

One Step ◽

Polymerase Chain

Abstract Background Coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2, is posing a serious threat to global public health. Reverse transcriptase real-time quantitative polymerase chain reaction (qRT-PCR) is widely used as the gold standard for clinical detection of SARS-CoV-2. Due to technical limitations, the reported positive rates of qRT-PCR assay of throat swab samples vary from 30 to 60%. Therefore, the evaluation of alternative strategies to overcome the limitations of qRT-PCR is required. A previous study reported that one-step nested (OSN)-qRT-PCR revealed better suitability for detecting SARS-CoV-2. However, information on the analytical performance of OSN-qRT-PCR is insufficient. Method In this study, we aimed to analyze OSN-qRT-PCR by comparing it with droplet digital PCR (ddPCR) and qRT-PCR by using a dilution series of SARS-CoV-2 pseudoviral RNA and a quality assessment panel. The clinical performance of OSN-qRT-PCR was also validated and compared with ddPCR and qRT-PCR using specimens from COVID-19 patients. Result The limit of detection (copies/ml) of qRT-PCR, ddPCR, and OSN-qRT-PCR were 520.1 (95% CI: 363.23–1145.69) for ORF1ab and 528.1 (95% CI: 347.7–1248.7) for N, 401.8 (95% CI: 284.8–938.3) for ORF1ab and 336.8 (95% CI: 244.6–792.5) for N, and 194.74 (95% CI: 139.7–430.9) for ORF1ab and 189.1 (95% CI: 130.9–433.9) for N, respectively. Of the 34 clinical samples from COVID-19 patients, the positive rates of OSN-qRT-PCR, ddPCR, and qRT-PCR were 82.35% (28/34), 67.65% (23/34), and 58.82% (20/34), respectively. Conclusion In conclusion, the highly sensitive and specific OSN-qRT-PCR assay is superior to ddPCR and qRT-PCR assays, showing great potential as a technique for detection of SARS-CoV-2 in patients with low viral loads.

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Analysis and validation of a highly sensitive one-step nested quantitative real-time polymerase chain reaction assay for specific detection of severe acute respiratory syndrome coronavirus 2

10.21203/rs.3.rs-74067/v1 ◽

2020 ◽

Author(s):

Yang Zhang ◽

Chunyang Dai ◽

Huiyan Wang ◽

Yong Gao ◽

Tuantuan Li ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Real Time ◽

Quantitative Polymerase Chain Reaction ◽

Clinical Samples ◽

Chain Reaction ◽

Pcr Assay ◽

Qrt Pcr ◽

Highly Sensitive ◽

One Step ◽

Polymerase Chain

Abstract Background Coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2, is posing a serious threat to global public health. Reverse transcriptase real-time quantitative polymerase chain reaction (qRT-PCR) is widely used as the gold standard for clinical detection of SARS-CoV-2. Due to technical limitations, the reported positive rates of qRT-PCR assay of throat swab samples vary from 30–60%. Therefore, the evaluation of alternative strategies to overcome the limitations of qRT-PCR is required. A previous study reported that one-step nested (OSN)-qRT-PCR revealed better suitability for detecting SARS-CoV-2. However, information on the analytical performance of OSN-qRT-PCR is insufficient. Method: In this study, we aimed to analyze OSN-qRT-PCR by comparing it with droplet digital PCR (ddPCR) and qRT-PCR by using a dilution series of SARS-CoV-2 pseudoviral RNA and a quality assessment panel. The clinical performance of OSN-qRT-PCR was also validated and compared with ddPCR and qRT-PCR using specimens from COVID-19 patients. Result The LoD (copies/ml) of qRT-PCR, ddPCR, and OSN-qRT-PCR were 520.1 (95% CI): 363.23–1145.69) for ORF1ab and 528.1 (95% CI: 347.7–1248.7) for N, 401.8 (95% CI: 284.8–938.3) for ORF1ab and 336.8 (95% CI: 244.6–792.5) for N, and 194.74 (95% CI: 139.7–430.9) for ORF1ab and 189.1 (95% CI: 130.9–433.9) for N, respectively. Of the 34 clinical samples from COVID-19 patients, the positive rates of OSN-qRT-PCR, ddPCR, and qRT-PCR were 82.35% (28/34), 67.65% (23/34), and 58.82% (20/34), respectively. Conclusion In conclusion, the highly sensitive and specific OSN-qRT-PCR assay is superior to ddPCR and qRT-PCR assays, showing great potential as a technique for detection of SARS-CoV-2 in patients with low viral loads.

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The real-time reverse transcription-polymerase chain reaction threshold cycle values for severe acute respiratory syndrome coronavirus 2 predict the prognosis of coronavirus disease 2019 pneumonia

Respiratory Investigation ◽

10.1016/j.resinv.2020.12.011 ◽

2021 ◽

Author(s):

Takahiro Fukushima ◽

Hiroki Kabata ◽

Ryo Yamamoto ◽

Tomohiro Suhara ◽

Yoshifumi Uwamino ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Severe Acute Respiratory Syndrome ◽

Real Time ◽

Reverse Transcription ◽

Reaction Threshold ◽

Chain Reaction ◽

The Real ◽

Polymerase Chain

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Multiple-Centre Clinical Evaluation of Rapid Recombinase-Aided Amplification Assays for Five Pathogens

10.21203/rs.3.rs-546696/v1 ◽

2021 ◽

Author(s):

Xin-xin Shen ◽

Dan-wen Nie ◽

Hong Zhang ◽

Zhi-fei Zhan ◽

Yuan Gao ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Real Time ◽

Reverse Transcription ◽

Clinical Performance ◽

Quantitative Polymerase Chain Reaction ◽

Human Adenovirus ◽

Molecular Diagnostic ◽

Chain Reaction ◽

Qrt Pcr ◽

Polymerase Chain

Abstract Background: Recombinase-aided amplification(RAA) is a new, simple, and ultrafast isothermal molecular diagnostic technique performed within 30min at 39°C–42°C.In this study, we evaluated the clinical performance of four duplex RAA kits for hepatitis B virus(HBV), human adenovirus 3(HAdV3), human adenovirus 7(HAdV7), and Bordetella pertussis and one duplex reverse-transcription RAA (RT-RAA) kit for respiratory syncytial virus (RSV).Methods: A total of 392 sera and 374 respiratory tract samples were collected from five institutions in four China regions. Each RAA kit’s sensitivity and specificity were compared with those of real-time quantitative polymerase chain reaction(qPCR),real-time quantitative reverse-transcription polymerase chain reaction(qRT-PCR), or sequencing. Results: Compared with qPCR or qRT-PCR, the sensitivities of HBV RAA,RSV RT-RAA, and B.pertussis RAA were 97.55%,96.67%, and 100%,respectively,and all of the specificities were 100%.The total coincidence rates were 97.78%(383/392,95%CI:95.63%–98.85%),97.70%(212/217, 95%CI:94.57%–99.16%), and 100%(60/60,95%CI:92.80%–100%),respectively.The Kappa values were 0.977,0.947, and 1,respectively(P<0.05).Regarding the sequencing, the sensitivities of HAdV3 RAA and HAdV7 RAA were 100% and 97.37%, respectively,and all specificities were 100%.The total coincidence rates were 100%(97/97,95%CI:91.58%–100%) and 98.97%(96/97,95%CI:94.39%–99.82%),and the Kappa values were 1 and 0.978 (P<0.05),respectively.Conclusions: With comparable clinical performance, these RAA kits are suitable assays for rapidly detecting pathogens in resource-limited laboratories.

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Analysis and validation of a highly sensitive one-step nested quantitative real-time polymerase chain reaction assay for specific detection of severe acute respiratory syndrome coronavirus 2

10.1101/2020.08.27.20182832 ◽

2020 ◽

Author(s):

Yang Zhang ◽

Chunyang Dai ◽

Huiyan Wang ◽

Yong Gao ◽

Tuantuan Li ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Real Time ◽

Quantitative Polymerase Chain Reaction ◽

Clinical Samples ◽

Chain Reaction ◽

Pcr Assay ◽

Qrt Pcr ◽

Highly Sensitive ◽

One Step ◽

Polymerase Chain

Coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2, is posing a serious threat to global public health. Reverse transcriptase real-time quantitative polymerase chain reaction (qRT-PCR) is widely used as the gold standard for clinical detection of SARS-CoV-2. Due to technical limitations, the reported positive rates of qRT-PCR assay of throat swab samples vary from 30%-60%. Therefore, the evaluation of alternative strategies to overcome the limitations of qRT-PCR is required. A previous study reported that one-step nested (OSN)-qRT-PCR revealed better suitability for detecting SARS-CoV-2. However, information on the analytical performance of OSN-qRT-PCR is insufficient. In this study, we aimed to analyze OSN-qRT-PCR by comparing it with droplet digital PCR (ddPCR) and qRT-PCR by using a dilution series of SARS-CoV-2 pseudoviral RNA and a quality assessment panel. The clinical performance of OSN-qRT-PCR was also validated and compared with ddPCR and qRT-PCR using specimens from COVID-19 patients. The LoD (copies/ml) of qRT-PCR, ddPCR, and OSN-qRT-PCR were 520.1 (95% CI): 363.23-1145.69) for ORF1ab and 528.1 (95% CI: 347.7-1248.7) for N, 401.8 (95% CI: 284.8-938.3) for ORF1ab and 336.8 (95% CI: 244.6-792.5) for N, and 194.74 (95% CI: 139.7-430.9) for ORF1ab and 189.1 (95% CI: 130.9-433.9) for N, respectively. Of the 34 clinical samples from COVID-19 patients, the positive rates of OSN-qRT-PCR, ddPCR, and qRT-PCR were 82.35% (28/34), 67.65% (23/34), and 58.82% (20/34), respectively. In conclusion, the highly sensitive and specific OSN-qRT-PCR assay is superior to ddPCR and qRT-PCR assays, showing great potential as a technique for detection of SARS-CoV-2 in patients with low viral loads.

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Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Infection in Febrile Infants Without Respiratory Distress

Clinical Infectious Diseases ◽

10.1093/cid/ciaa452 ◽

2020 ◽

Vol 71 (16) ◽

pp. 2243-2245 ◽

Cited By ~ 15

Author(s):

Michal Paret ◽

Jennifer Lighter ◽

Rebecca Pellett Madan ◽

Vanessa N Raabe ◽

Gail F Shust ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Severe Acute Respiratory Syndrome ◽

Respiratory Distress ◽

Real Time ◽

Reverse Transcription ◽

Bacterial Infections ◽

Chain Reaction ◽

Polymerase Chain

Abstract We report 2 cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (COVID-19) in infants presenting with fever in the absence of respiratory distress who required hospitalization for evaluation of possible invasive bacterial infections. The diagnoses resulted from routine isolation and real-time reverse-transcription polymerase chain reaction–based testing for SARS-CoV-2 for febrile infants in an outbreak setting.

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MMP1 is a Promiseful Prognostic Biomarker and Correlating with Immune Infiltrates in Hepatocellular Carcinoma

10.21203/rs.3.rs-547264/v1 ◽

2021 ◽

Author(s):

Lei Dai ◽

Joseph Muggnyi ◽

xingchen cai ◽

shuqi mao ◽

tongyue zhang ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Real Time ◽

Reverse Transcription ◽

Clinical Performance ◽

Quantitative Polymerase Chain Reaction ◽

Human Adenovirus ◽

Molecular Diagnostic ◽

Chain Reaction ◽

Qrt Pcr ◽

Polymerase Chain

Abstract Background: Recombinase-aided amplification(RAA) is a new, simple, and ultrafast isothermal molecular diagnostic technique performed within 30min at 39°C–42°C.In this study, we evaluated the clinical performance of four duplex RAA kits for hepatitis B virus(HBV), human adenovirus 3(HAdV3), human adenovirus 7(HAdV7), and Bordetella pertussis and one duplex reverse-transcription RAA (RT-RAA) kit for respiratory syncytial virus (RSV).Methods: A total of 392 sera and 374 respiratory tract samples were collected from five institutions in four China regions. Each RAA kit’s sensitivity and specificity were compared with those of real-time quantitative polymerase chain reaction(qPCR),real-time quantitative reverse-transcription polymerase chain reaction(qRT-PCR), or sequencing. Results: Compared with qPCR or qRT-PCR, the sensitivities of HBV RAA,RSV RT-RAA, and B.pertussis RAA were 97.55%,96.67%, and 100%,respectively,and all of the specificities were 100%.The total coincidence rates were 97.78%(383/392,95%CI:95.63%–98.85%),97.70%(212/217, 95%CI:94.57%–99.16%), and 100%(60/60,95%CI:92.80%–100%),respectively. The Kappa values were 0.977,0.947, and 1,respectively(P<0.05).Regarding the sequencing, the sensitivities of HAdV3 RAA and HAdV7 RAA were 100% and 97.37%, respectively, and all specificities were 100%.The total coincidence rates were 100%(97/97,95%CI:91.58%–100%) and 98.97%(96/97,95%CI:94.39%–99.82%),and the Kappa values were 1 and 0.978 (P<0.05),respectively.Conclusions: With comparable clinical performance, these RAA kits are suitable assays for rapidly detecting pathogens in resource-limited laboratories.

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Sensitive quantitative and rapid immunochromatographic diagnosis of clinical samples by scanning electron microscopy - preparing for future outbreaks

10.1101/2020.05.20.20106864 ◽

2020 ◽

Author(s):

Hideya Kawasaki ◽

Hiromi Suzuki ◽

Masato Maekawa ◽

Takahiko Hariyama

Keyword(s):

Electron Microscopy ◽

Polymerase Chain Reaction ◽

Real Time ◽

Reverse Transcription ◽

Influenza A ◽

Clinical Samples ◽

Chain Reaction ◽

Detection Ability ◽

Polymerase Chain ◽

Scanning Electron

AbstractBackgroundAs pathogens such as influenza virus and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can easily cause pandemics, rapid diagnostic tests are crucial for implementing efficient quarantine measures, providing effective treatments to patients, and preventing or containing a pandemic infection. Here, we developed the immunochromatography-NanoSuit® method, an improved immunochromatography method combined with a conventional scanning electron microscope (SEM), which enables observation of immunocomplexes labeled with a colloidal metal.Methods and FindingsThe detection ability of our method is comparable to that of real-time reverse transcription-polymerase chain reaction and the detection time is approximately 15 min. Our new immunochromatography-NanoSuit® method suppresses cellulose deformity and makes it possible to easily focus and acquire high-resolution images of gold/platinum labeled immunocomplexes of viruses such as influenza A, without the need for conductive treatment as with conventional SEM. Electron microscopy (EM)-based diagnosis of influenza A exhibited 94% clinical sensitivity (29/31) (95% confidence interval [95%CI]: 78.58–99.21%) and 100% clinical specificity (95%CI: 97.80–100%). EM-based diagnosis was significantly more sensitive (71.2%) than macroscopic diagnosis (14.3%), especially in the lower influenza A-RNA copy number group. The detection ability of our method is comparable to that of real-time reverse transcription-polymerase chain reaction.ConclusionsThis simple and highly sensitive quantitative analysis method involving immunochromatography can be utilized to diagnose various infections in humans and livestock, including highly infectious diseases such as COVID-19.

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