Establishment and evaluation of real-time PCR for West Nile virus detection

2009 ◽  
Vol 6 (1) ◽  
pp. 55-59 ◽  
Author(s):  
Shi Li-Jun ◽  
Lu Mao-Min ◽  
Li Gang ◽  
Li Cheng-Yao ◽  
Zhang Jin-Gang

AbstractA rapid real-time polymerase chain reaction (RT-PCR) for detecting West Nile virus (WNV) was established. Primers were designed according to the sequence of the capsid protein gene of WNV by Primer Premier 5.0. In this way, an inexpensive assay using the intercalating dye SYBR Green I was developed and validated. The amplifying curve showed that this method could successfully amplify 102 copies/μl of the WNV gene, while reference to Japanese encephalitis virus (JEV) and blank control were all negative. Tenfold successive dilutions of positive WNV DNA were used to measure the sensitivity of RT-PCR. The assay system showed high reproducibility with coefficient of variation (CV) <2%. Thus the newly established RT-PCR assay was shown to be a rapid, sensitive and specific test for detecting WNV.

Plant Disease ◽  
2013 ◽  
Vol 97 (5) ◽  
pp. 641-644 ◽  
Author(s):  
Manphool S. Fageria ◽  
Mathuresh Singh ◽  
Upeksha Nanayakkara ◽  
Yvan Pelletier ◽  
Xianzhou Nie ◽  
...  

The current-season spread of Potato virus Y (PVY) was investigated in New Brunswick, Canada, in 11 potato fields planted with six different cultivars in 2009 and 2010. In all, 100 plants selected from each field were monitored for current-season PVY infections using enzyme-linked immunosorbent assay (ELISA) and real-time reverse-transcription polymerase chain reaction (RT-PCR) assay. Average PVY incidence in fields increased from 0.6% in 2009 and 2% in 2010 in the leaves to 20.3% in 2009 and 21.9% in 2010 in the tubers at the time of harvest. In individual fields, PVY incidence in tubers reached as high as 37% in 2009 and 39% in 2010 at the time of harvest. Real-time RT-PCR assay detected more samples with PVY from leaves than did ELISA. A higher number of positive samples was also detected with real-time RT-PCR from growing tubers compared with the leaves collected from the same plant at the same sampling time. PVY incidence determined from the growing tubers showed a significant positive correlation with the PVY incidence of tubers after harvest. Preharvest testing provides another option to growers to either top-kill the crop immediately to secure the seed market when the PVY incidence is low or leave the tubers to develop further for table or processing purposes when incidence of PVY is high.


2006 ◽  
Vol 89 (5) ◽  
pp. 1335-1340
Author(s):  
Amir Abdulmawjood ◽  
Holger Schnenbrcher ◽  
Michael BÜlte

Abstract A collaborative trial was conducted to evaluate a real-time reverse transcriptase-polymerase chain reaction (RT-PCR) assay for detection of central nervous system (CNS) tissues in meat products (e.g., sausages). The method is based on the detection of ruminant glial fibrillary acidic protein (GFAP) mRNA by applying real-time RT-PCR. The assay was evaluated through a multicenter trial involving 12 participating laboratories that received coded cDNA obtained from 3 different types of sausages. The participants used 5 different real-time detection systems. The results obtained in this validation revealed that this real-time RT-PCR assay performed well in the different laboratories with a detection limit of at least 0.1% CNS in those test materials that contained strongly heat-treated samples (sausages cooked at 120C) and the medium heat-treated samples (sausages cooked at 80C). The detection limit of liver sausages was determined to be 0.2% of CNS. Neither the samples with no CNS additive nor the bovine DNA and the negative control containing 100% swine brain gave any positive signals. The presented results indicate that the real-time RT-PCR assay was just as reproducible between laboratories, as repeatable within a laboratory, could reliably be used for detection of bovine spongiform encephalopathy risk material in meat and meat products, and signify that it may be used with confidence in any laboratory.


2004 ◽  
Vol 72 (3) ◽  
pp. 496-501 ◽  
Author(s):  
Xiaoli L. Pang ◽  
Bonita Lee ◽  
Nasim Boroumand ◽  
Barbara Leblanc ◽  
Jutta K. Preiksaitis ◽  
...  

2006 ◽  
Vol 18 (5) ◽  
pp. 459-462 ◽  
Author(s):  
Miguel Angel Jiménez-Clavero ◽  
Montserrat Agüero ◽  
Gema Rojo ◽  
Concepción Gómez-Tejedor
Keyword(s):  
Rt Pcr ◽  

2020 ◽  
Vol 13 (10) ◽  
Author(s):  
Jae Woong Lee ◽  
Yu-Jung Won ◽  
Sung-Geun Lee ◽  
Soon-Young Paik

Background: The West Nile Virus (WNV), discovered in New York, USA in 1999 after it was first isolated in Uganda in 1937, has since spread not only in the United States but also around the world. Africa, Eurasia, Australia, and the Middle East have sporadic cases of the disease. Objectives: We aimed to find real-time reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay to be more sensitive than conventional RT-PCR, and more rapid and efficient than conventional RT-PCR and real-time RT-PCR for WNV detection. Methods: A total of 32 genomic sequences from different strains of WNV were analyzed to identify conserved nucleotide sequence regions. Six WNV specific RT-LAMP primers targeting the E gene were designed. Results: The novel primer for the real-time RT-LAMP assay can detect WNV with high specificity. The efficiency of the real-time RT-LAMP assay is higher than the conventional RT-PCR and real-time RT-PCR. Real-time RT-PCR and conventional PCR require at least 30 – 40 min and 2 h, respectively, to yield results, whereas real-time RT-LAMP provides positive results in only 10 – 20 min. Conclusions: The novel primers were developed by analyzing of 32 genomic sequences of WNV strains. The primers were designed from the most conserved region of the E gene for real-time RT-LAMP. The LAMP assay is a rapid, efficient, highly sensitive, and specific tool for the identification of WNV.


2021 ◽  
Author(s):  
Emmanuel Oladipo Babafemi

Abstract Background: COVID-19 has spread globally since its discovery in Hubei province, China in December 2019 and became pandemic in 2020. COVID-19 is a new betacoronavirus and a variant of severe acute respiratory syndrome coronavirus 2 (SARA- CoV-2). Rapid, accurate and reliable diagnosis of COVID-19 will prevent the spread and allow for appropriate management. The main objective of this systematic review is to identify, appraise and summarise the published evidence on the diagnostic performance and effectiveness of SARS-CoV-2 virus in the diagnosis of current or previous COVID-19 using real-time polymerase chain reaction (RT-PCR) assay in low-and middle-income countries (LMICs). Methods: We will search MEDLINE/PubMed, EMBASE, BIOSIS, LILACS, Cochrane Infectious Diseases Group Specialised Register (CIDG SR), Global Health, and CINAHL for published studies for the diagnosis of COVID-19 using real-time polymerase chain reaction assay in LMICs There will be no restriction regarding the language, date of publication, and publication status. We will include retrospective, cross-sectional and cohort observational studies will be included in the review. Selection of studies, data extraction and management, assessment of risk of bias, and quality of evidence will be performed by two independent reviewers (EB and BC). A third researcher (GM) will be consulted in case of discrepancies. Depending on the availability and quality of the data, a meta-analysis will be performed. Otherwise, findings will be qualitatively reported. Discussion: To our knowledge, this is the first systematic review and meta-analysis to assess the uptake of RT-PCR assay for SARS-CoV-2 detection from clinical samples in human in LMICs. This review will make available evidence on the uptake, accuracy, approach, and interpretation of results of this assay in the context of COVID-19 diagnosis which will meet an urgent need, considering the diagnostic challenges of RT-PCR assay for COVID-19 diagnosis in humans. Systematic review registration: PROSPERO CRD42021271894


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