Sustained Positivity of The Real-time Polymerase Chain Reaction (PCR) Test for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in Two Patients with Novel Coronavirus Disease-2019 (COVID-19)

Abstract Utilizing results of polymerase chain reaction (PCR) testing and subsequent antibody titers, we report on the test characteristics of a PCR screening test for severe acute respiratory syndrome coronavirus 2 among hospital workers. The PCR test was found to be 87% sensitive and 97% specific, with a positive predictive value of 0.98 and a negative predictive value of 0.80.

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Multiplex Real-Time Reverse-Transcription Polymerase Chain Reaction Assays for Diagnostic Testing of Severe Acute Respiratory Syndrome Coronavirus 2 and Seasonal Influenza Viruses: A Challenge of the Phase 3 Pandemic Setting

The Journal of Infectious Diseases ◽

10.1093/infdis/jiaa658 ◽

2020 ◽

Author(s):

Fabiola Mancini ◽

Fabrizio Barbanti ◽

Maria Scaturro ◽

Stefano Fontana ◽

Angela Di Martino ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Severe Acute Respiratory Syndrome ◽

Real Time ◽

Reverse Transcription ◽

Seasonal Influenza ◽

Influenza Viruses ◽

Activity Period ◽

Clinical Samples ◽

Chain Reaction ◽

Polymerase Chain

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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Presymptomatic Transmission of Severe Acute Respiratory Syndrome Coronavirus 2 Among Residents and Staff at a Skilled Nursing Facility: Results of Real-time Polymerase Chain Reaction and Serologic Testing

Clinical Infectious Diseases ◽

10.1093/cid/ciaa991 ◽

2020 ◽

Cited By ~ 8

Author(s):

Scott A Goldberg ◽

Jochen Lennerz ◽

Michael Klompas ◽

Eden Mark ◽

Virginia M Pierce ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Severe Acute Respiratory Syndrome ◽

Real Time ◽

Skilled Nursing Facility ◽

Chain Reaction ◽

Nursing Facility ◽

Skilled Nursing ◽

Routine Testing ◽

Serologic Testing ◽

Polymerase Chain

Abstract High rates of asymptomatic coronavirus disease 2019 infection suggest benefits to routine testing in congregate care settings. Screening was undertaken in a single nursing facility without a known case of coronavirus disease 2019, demonstrating an 85% prevalence among residents and 37% among staff. Serology was not helpful in identifying infections.

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Comparison of real-time polymerase chain reaction and end-point polymerase chain reaction for the analysis of gene expression in preimplantation embryos

Reproduction Fertility and Development ◽

10.1071/rd05012 ◽

2006 ◽

Vol 18 (3) ◽

pp. 365 ◽

Cited By ~ 17

Author(s):

Árpád Baji Gál ◽

Joseph Wallace Carnwath ◽

Andras Dinnyes ◽

Doris Herrmann ◽

Heiner Niemann ◽

...

Keyword(s):

Gene Expression ◽

Polymerase Chain Reaction ◽

Real Time ◽

Reverse Transcription ◽

Dynamic Range ◽

Chain Reaction ◽

Real Time System ◽

The Real ◽

End Point ◽

Polymerase Chain

The aim of the present study was to compare real-time polymerase chain reaction (PCR) and end-point PCR with respect to their suitability for the analysis of gene expression in samples in which the number of cells is limited; for example, in studies of preimplantation embryonic development and to determine the variability of the real-time reverse transcription–PCR assay. The sensitivity, dynamic range and precision of both PCR systems were compared using a single mouse liver cDNA standard. The real-time system was 100-fold more sensitive than the end-point system and had a dynamic range of more than four orders of magnitude. The linear range for end-point PCR extended for two orders of magnitude using a fixed end-point of 31 cycles. The percentage standard error of the mean based on 30 replicates was 0.14% of the threshold cycle (Ct) value for the real-time system and 6.8% for the end-point fluorescence intensity. The coefficients of variation (CV) for reverse transcription combined with real-time analysis and the complete gene expression protocol consisting of mRNA isolation, reverse transcription and real-time PCR analysis were 0.6% and 1.4% of the Ct values, respectively. The present paper details, for the first time, measurement of the biological variation of individual mammalian oocytes. The CV was 1.8% of the Ct value for expression analysis of six bovine oocytes. The results are discussed in relation to the analysis of gene expression in preimplantation embryo development.

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Perspective of Arguments in Public Health

Journal of Comprehensive Health ◽

10.53553/jch.v09i01.010 ◽

2021 ◽

Vol 9 (1) ◽

pp. 44-45

Author(s):

Dinesh Kumar

Keyword(s):

Polymerase Chain Reaction ◽

Real Time ◽

Respiratory Symptoms ◽

False Negative ◽

Rt Pcr ◽

Chain Reaction ◽

Negative Report ◽

Polymerase Chain ◽

Time Of Admission ◽

Pcr Test

Recently, an argument was put forth because a symptomatic and positive patient for CoVID-19 turned tested negative after 7 days, so discharged from the hospital. Both at the time of admission and discharge real-time reverse transcriptase Polymerase Chain Reaction (RT-PCR) was done for testing of CoVID-19. Immediately, patient again developed respiratory symptoms and was admitted to hospital again. Amidst of current CoVID-19 pandemic, a question was asked “What is the specificity of the Real Time-Polymerase Chain Reaction (RT-PCR) test for COVID-19?” with an assumption that what if at the time of discharge the disease is present in patient but test turned out to be negative? In response to that a counter statement was posed that “It is the sensitivity that should be asked rather than specificity”. It was based on the implication of primary question that was implying false negative report of the RT-PCR. It means, since patient was discharged with negative result that could be false negative.

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Reducing False Negative PCR Test for COVID-19

International Journal of MCH and AIDS (IJMA) ◽

10.21106/ijma.421 ◽

2020 ◽

Vol 9 (3) ◽

pp. 408-410

Author(s):

Fatemeh Bahreini ◽

Rezvan Najafi ◽

Razieh Amini ◽

Salman Khazaei ◽

Saeid Bashirian

Keyword(s):

Polymerase Chain Reaction ◽

Real Time ◽

False Negative ◽

Rt Pcr ◽

Chain Reaction ◽

Creative Commons ◽

Negative Results ◽

False Negative Results ◽

Polymerase Chain ◽

Pcr Test

As the SARS-CoV-2 (COVID-19) pandemic spreads rapidly, there is need for a diagnostic test with high accuracy to detect infected individuals especially those without symptoms. Real-time polymerase chain reaction (RT-PCR) is a common molecular test for diagnosing SARS-CoV-2. If some factors are not taken into consideration when performing this test, it can have a relatively large number of false negative results. In this article, we discuss important considerations that could lead to false negative test reduction. Key words: • SARS-CoV-2 • COVID-19 • Real time polymerase chain reaction • RT-PCR test • Diagnosis • False negatives • Genetics • Emerging disease Copyright © 2020 Bahreini et al. Published by Global Health and Education Projects, Inc. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0)which permits unrestricted use, distribution, and reproduction in any medium, provided the original work, first published in this journal, is properly cited.

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