scholarly journals Detection of influenza A virus RNA in birds by optimized Real—Time PCR system

2010 ◽  
Vol 3 (5) ◽  
pp. 337-340
Author(s):  
Ph A Ilinykh ◽  
EM Shestopalova ◽  
Yu I Khripko ◽  
AG Durimanov ◽  
KA Sharshov ◽  
...  
Keyword(s):  
Real Time ◽  
Influenza A Virus ◽  
Real Time Pcr ◽  
Influenza A ◽  
Virus Rna

scholarly journals Clinical Investigations. Comparison of Directigen Flu A+B with Real Time PCR in the Diagnosis of Influenza / Сравнение Иммунохроматографического Метода (Directigen Flu A+B) И Теста RT-PCR При Инфекциях Гриппа

Folia Medica ◽  
2015 ◽  
Vol 57 (2) ◽  
pp. 104-110 ◽  
Author(s):  
Golubinka Bosevska ◽  
Nikola Panovski ◽  
Elizabeta Janceska ◽  
Vladimir Mikik ◽  
Irena Kondova Topuzovska ◽  
...  
Keyword(s):  
Real Time ◽  
Influenza A Virus ◽  
Real Time Pcr ◽  
Influenza A ◽  
Age Groups ◽  
Influenza Viruses ◽  
Influenza B Virus ◽  
Influenza B ◽  
B Virus ◽  
Nose And Throat

AbstractEarly diagnosis and treatment of patients with influenza is the reason why physicians need rapid high-sensitivity influenza diagnostic tests that require no complex lab equipment and can be performed and interpreted within 15 min. The Aim of this study was to compare the rapid Directigen Flu A+B test with real time PCR for detection of influenza viruses in the Republic of Macedonia. MATERIALS AND METHODS: One-hundred-eight respiratory samples (combined nose and throat swabs) were routinely collected for detection of influenza virus during influenza seasons. Forty-one patients were pediatric cases and 59 were adult. Their mean age was 23 years. The patients were allocated into 6 age groups: 0 - 4 yrs, 5 - 9 yrs, 10 - 14 yrs, 15 - 19 yrs, 20-64 yrs and > 65 yrs. Each sample was tested with Directigen Flu A+B and CDC real time PCR kit for detection and typisation/subtypisation of influenza according to the lab diagnostic protocol. RESULTS: Directigen Flu A+B identified influenza A virus in 20 (18.5%) samples and influenza B virus in two 2 (1.9%) samples. The high specificity (100%) and PPV of Directigen Flu A+B we found in our study shows that the positive results do not need to be confirmed. The overall sensitivity of Directigen Flu A+B is 35.1% for influenza A virus and 33.0% for influenza B virus. The sensitivity for influenza A is higher among children hospitalized (45.0%) and outpatients (40.0%) versus adults. CONCLUSION: Directigen Flu A+B has relatively low sensitivity for detection of influenza viruses in combined nose and throat swabs. Negative results must be confirmed.

scholarly journals Objective pathogen monitoring in nursery and finisher pigs by monthly laboratory diagnostic testing

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Nicole B. Goecke ◽  
Maja Kobberø ◽  
Thomas K. Kusk ◽  
Charlotte K. Hjulsager ◽  
Ken Steen Pedersen ◽  
...  
Keyword(s):  
Real Time ◽  
San Francisco ◽  
Influenza A Virus ◽  
High Throughput ◽  
Real Time Pcr ◽  
Influenza A ◽  
Clinical Signs ◽  
Swine Influenza ◽  
Porcine Cytomegalovirus ◽  
Swine Influenza A Virus

Abstract Background Infectious diseases are of great economic importance in commercial pig production, causing both clinical and subclinical disease, with influence on welfare, productivity, and antibiotic use. The causes of these diseases are often multifactorial and laboratory diagnostics are seldom routinely performed. The aim of the present study was to explore the benefits of monthly pathogen monitoring in nursery and finisher herds and to examine association between laboratory results and observed clinical signs, including coughing and diarrhoea. Three monthly samplings were conducted in three different age groups in six nursery and four finisher production units. For each unit, two pens were randomly selected in each age group and evaluated for coughing and diarrhoea events. Furthermore, faecal sock and oral fluid samples were collected in the selected pens and analysed for 18 respiratory and enteric viral and bacterial pathogens using the high-throughput real-time PCR BioMark HD platform (Fluidigm, South San Francisco, USA). Results In total, 174 pens were sampled in which eight coughing events and 77 diarrhoeic events were observed. The overall findings showed that swine influenza A virus, porcine circovirus 2, porcine cytomegalovirus, Brachyspira pilosicoli, Lawsonia intracellularis, Escherichia coli fimbria types F4 and F18 were found to be prevalent in several of the herds. Association between coughing events and the presence of swine influenza A virus, porcine cytomegalovirus (Cq ≤ 20) or a combination of these were found. Furthermore, an association between diarrhoeic events and the presence of L. intracellularis (Cq ≤ 24) or B. pilosicoli (Cq ≤ 26) was found. Conclusions The use of high-throughput real-time PCR analysis for continuous monitoring of pathogens and thereby dynamics of infections in a pig herd, provided the veterinarian and farmer with an objective knowledge on the distribution of pathogens in the herd. In addition, the use of a high-throughput method in combination with information about clinical signs, productivity, health status and antibiotic consumption, presents a new and innovative way of diagnosing and monitoring pig herds and even to a lower cost than the traditional method.

A real-time PCR assay for the monitoring of influenza a virus in wild birds

2007 ◽  
Vol 144 (1-2) ◽  
pp. 27-31 ◽  
Author(s):  
Malin Karlsson ◽  
Anders Wallensten ◽  
Åke Lundkvist ◽  
Björn Olsen ◽  
Maria Brytting
Keyword(s):  
Real Time ◽  
Influenza A Virus ◽  
Real Time Pcr ◽  
Influenza A ◽  
Wild Birds ◽  
Pcr Assay

scholarly journals Anti-influenza A virus activity of two Newtonia species and the isolated compound myricetin-3-o-rhamnoside

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Katlego E. Motlhatlego ◽  
Parvaneh Mehrbod ◽  
Fatemeh Fotouhi ◽  
Muna Ali Abdalla ◽  
Jacobus N. Eloff ◽  
...  
Keyword(s):  
Real Time ◽  
Influenza A Virus ◽  
Real Time Pcr ◽  
Influenza A ◽  
Combined Treatment ◽  
Model Organism ◽  
Quantitative Real Time Pcr ◽  
Leaf Extracts ◽  
Viral Attachment ◽  
Isolated Compound

Abstract Background Some viruses play a key role in the disturbance of the digestive system. The common viruses which cause infectious diarrhoea (gastroenteritis) include astrovirus, caliciviruses, coronavirus and torovirus which are single-stranded RNA viruses. Influenza A virus (H1N1) also causes diarrhoea in addition to being associated with respiratory symptoms. In preliminary studies, Newtonia hildebrandtii and N. buchananii leaf extracts had good antibacterial activity against some bacteria implicated in causing diarrhoea. The aim of this study was to evaluate the anti-influenza activity of two Newtonia species extracts and the isolated compound (myricitrin). Methods N. hildebrandtii and N. buchananii acetone, and MeOH: DCM (methanol-dichloromethane) leaf and stem extracts, and an antibacterial compound myricetin-3-o-rhamnoside (myricitrin), isolated from N. buchananii, were evaluated for their antiviral efficacy against influenza A virus (IAV) PR8/34/H1N1 as a model organism. The MTT and hemagglutination assays were used to assess the extracts and compound interference with cell viability and viral surface HA glycoprotein. The quantitative real-time PCR was performed to assess the viral load. Results Plant extracts of N. hildebrandtii and N. buchananii were effective against IAV. The extracts in combination with H1N1 showed highly significant antiviral activity (P < 0.01) and maintained cell viabilities (P < 0.05). Myricitrin was non-cytotoxic at concentration 104 μg/ml. Myricitrin was most effective against IAV in a co-penetration combined treatment, thereby confirming the inhibitory effect of this compound in the viral attachment and entry stages. Myricitrin treatment also resulted in the highest viability of the cells in co-penetration treatment. The activity of myricitrin indicates the potential of the extracts in controlling viral infection at the attachment stage. The antiviral effect of myricitrin on IAV load in MDCK cell culture was confirmed using quantitative real-time PCR. Conclusion Data from this study support further research and development on Newtonia hildebrandtii, Newtonia buchananii and myricitrin to address diarrhoea and related conditions caused by viruses in both human and veterinary medicine. Further work needs to be conducted on the activity of the extracts and the purified compound on other viruses of importance which have similar symptoms to influenza virus such as the coronavirus which led to a recent global pandemic.

scholarly journals Clinical Evaluation of the New High-Throughput Luminex NxTAG Respiratory Pathogen Panel Assay for Multiplex Respiratory Pathogen Detection

2016 ◽  
Vol 54 (7) ◽  
pp. 1820-1825 ◽  
Author(s):  
Jonathan H. K. Chen ◽  
Ho-Yin Lam ◽  
Cyril C. Y. Yip ◽  
Sally C. Y. Wong ◽  
Jasper F. W. Chan ◽  
...  
Keyword(s):  
Real Time ◽  
Influenza A Virus ◽  
Real Time Pcr ◽  
Influenza A ◽  
Respiratory Pathogen ◽  
Gene Target ◽  
Viral Culture ◽  
Matrix Gene ◽  
Sample Throughput ◽  
Respiratory Specimens

A broad range of viral and bacterial pathogens can cause acute respiratory tract infection. For rapid detection of a broad respiratory pathogen spectrum, multiplex real-time PCR is ideal. This study evaluated the performance of the new Luminex NxTAG Respiratory Pathogen Panel (NxTAG-RPP) in comparison with the BioFire FilmArray Respiratory Panel (FA-RP) or singleplex real-time PCR as reference. A total of 284 clinical respiratory specimens and 3 influenza A/H7N9 viral culture samples were tested. All clinical specimens were processed and analyzed in parallel using NxTAG-RPP and the reference standard method. The H7N9 viral culture samples were tested using NxTAG-RPP only. Overall, the NxTAG-RPP demonstrated ≥93% sensitivity and specificity for all respiratory targets except human coronavirus OC43 (HCoV-OC43) and HCoV-HKU1. The H7N9 virus was detected by the influenza A virus matrix gene target, while other influenza A virus subtyping gene targets in the panel remained negative. Complete concordance between NxTAG-RPP and FA-RP was observed in 98.8% (318/322) of positive results (kappa = 0.92). Substantial agreement was found for most respiratory targets, but significant differences were observed in human metapneumovirus (P= 0.001) and parainfluenza virus type 3 (P= 0.031). NxTAG-RPP has a higher sample throughput than FA-RP (96 samples versus 1 sample per run) while the turnaround times for NxTAG-RPP and FA-RP were 5 h (up to 96 samples) and 1 h (for one sample), respectively. Overall, NxTAG-RPP demonstrated good diagnostic performance for most respiratory pathogens. The high sample throughput with reasonable turnaround time of this new assay makes it a suitable multiplex platform for routine screening of respiratory specimens in hospital-based laboratories.

scholarly journals A multiplex real-time PCR assay for detection of oseltamivir-resistant strains of influenza virus

2014 ◽  
Vol 9 (6) ◽  
pp. 628-633
Author(s):  
Dawid Nidzworski ◽  
Joanna Dobkowska ◽  
Marcin Hołysz ◽  
Beata Gromadzka ◽  
Bogusław Szewczyk
Keyword(s):  
Real Time ◽  
Influenza A Virus ◽  
Real Time Pcr ◽  
Influenza A ◽  
Influenza Pandemic ◽  
Neuraminidase Inhibitor ◽  
Influenza Viruses ◽  
Antigenic Drift ◽  
Influenza A Viruses ◽  
Oseltamivir Resistance

AbstractInfluenza is a contagious disease of humans and animals caused by viruses belonging to the Orthomyxoviridae family. The influenza A virus genome consists of negative sense, single-stranded, segmented RNA. Influenza viruses are classified into subtypes based on two surface antigens known as hemagglutinin (H) and neuraminidase (N). The main problem with influenza A viruses infecting humans is drug resistance, which is caused by antigenic changes. A few antiviral drugs are available, but the most popular is the neuraminidase inhibitor — oseltamivir. The resistance against this drug has probably developed through antigenic drift by a point mutation in one amino acid at position 275 (H275Y). In order to prevent a possible influenza pandemic it is necessary to develop fast diagnostic tests. The aim of this project was to develop a new test for detection of influenza A virus and determination of oseltamivir resistance/sensitivity in humans. Detection and differentiation of oseltamivir resistance/sensitivity of influenza A virus was based on real-time PCR. This test contains two TaqMan probes, which work at different wavelengths. Application of techniques like multiplex real-time PCR has greatly enhanced the capability for surveillance and characterization of influenza viruses. After its potential validation, this test can be used for diagnosis before treatment.

scholarly journals Performance Evaluation of Allplex Respiratory Panels 1, 2, and 3 for Detection of Respiratory Viruses and Influenza A Virus Subtypes

2016 ◽  
Vol 55 (2) ◽  
pp. 479-484 ◽  
Author(s):  
Hee Jae Huh ◽  
Ji-Youn Kim ◽  
Hyeon Jeong Kwon ◽  
Sun Ae Yun ◽  
Myoung-Keun Lee ◽  
...  
Keyword(s):  
Real Time ◽  
Influenza A Virus ◽  
Real Time Pcr ◽  
Influenza A ◽  
Respiratory Viruses ◽  
Reverse Transcription Pcr ◽  
Percent Agreement ◽  
One Step ◽  
Multiple Detection ◽  
Time Required

ABSTRACTThe Allplex respiratory panels 1, 2, and 3 (Allplex) comprise a one-step real-time reverse transcription-PCR assay for the detection of respiratory viruses (RVs) and influenza A subtypes based on multiple detection temperature (MuDT) technology. The performance of the Allplex assay was compared with those of the AdvanSure RV real-time PCR kit (AdvanSure) and the PowerChek pandemic H1N1/H3N2/H5N1 real-time PCR kit (PowerChek) using 417 clinical respiratory specimens. In comparison with the AdvanSure assay for RV detection by each virus, the ranges of positive percent agreement, negative percent agreement, and kappa values with the Allplex assay were 82.8 to 100%, 95.5 to 100%, and 0.85 to 1.00, respectively. For influenza A virus (INF A) subtyping, the kappa values between the Allplex and PowerChek assays were 0.67 and 1.00 for the INF A H1N1-pdm09 and H3 subtypes, respectively. Uniplex PCR and sequencing for samples with discrepant results demonstrated that the majority of results were concordant with those from the Allplex assay. When testing 24 samples, the turnaround and hands-on time required to perform the Allplex assay were 4 h 15 min and 15 min, respectively. In conclusion, the Allplex assay produced results comparable to those from the AdvanSure and PowerChek assays.

scholarly journals Laboratory validation of an RNA/DNA hybrid tagmentation based mNGS workflow on SARS-CoV-2 and other respiratory RNA viruses detection

2020 ◽  
Author(s):  
Feili Wei ◽  
Yanhua Yu ◽  
Zhongjie Hu ◽  
Rui Wang ◽  
Xianghua Guo ◽  
...  
Keyword(s):  
Real Time ◽  
Influenza A Virus ◽  
Real Time Pcr ◽  
Influenza A ◽  
Rna Viruses ◽  
Handling Time ◽  
Respiratory Pathogens ◽  
Quantitative Real Time Pcr ◽  
Tn5 Transposon ◽  
Significant Difference

Background: Acute respiratory infection caused by RNA viruses is still one of the main diseases all over the world such as SARS CoV 2 and Influenza A virus. mNGS was a powerful tool for ethological diagnosis. But there were some challenges during mNGS implementation in clinical settings such as time consuming manipulation and lack of comprehensive analytical validation. Methods: We set up CATCH that was a mNGS method based on RNA and DNA hybrid tagmentation via Tn5 transposon. Seven respiratory RNA viruses and three subtypes of Influenza A virus had been used to test capabilities of CATCH on detection and quantification. Analytical performance of SARS CoV 2 and Influenza A virus had been determined with reference standards. We compared accuracy of CATCH with quantitative real time PCR by using clinical 98 samples from 64 COVID19 patients. Results: We minimized the library preparation process to 3 hours and handling time to 35 minutes. Duplicate filtered RPM of 7 respiratory viruses and 3 Influenza A virus subtypes were highly correlated with viral concentration. LOD of SARS CoV 2 was 39.2 copies/test and of Influenza A virus was 278.1 copies/mL. Comparing with quantitative real time PCR, the overall accuracy of CATCH was 91.4%. Sensitivity was 84.5% and specificity was 100%. Meanwhile, there were significant difference of microbial profile in oropharyngeal swabs among critical, moderate patients and healthy controls. Conclusion: Although further optimization is needed before CATCH can be rolled out as a routine diagnostic test, we highlight the potential impact of it advancing molecular diagnostics for respiratory pathogens.

Sign in / Sign up

Export Citation Format

Share Document