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1.
Infect Dis Poverty ; 11(1): 50, 2022 May 04.
Article in English | MEDLINE | ID: covidwho-1883543

ABSTRACT

BACKGROUND: Influenza B virus can cause epidemics with high pathogenicity, so it poses a serious threat to public health. A feature representation algorithm is proposed in this paper to identify the pathogenicity phenotype of influenza B virus. METHODS: The dataset included all 11 influenza virus proteins encoded in eight genome segments of 1724 strains. Two types of features were hierarchically used to build the prediction model. Amino acid features were directly delivered from 67 feature descriptors and input into the random forest classifier to output informative features about the class label and probabilistic prediction. The sequential forward search strategy was used to optimize the informative features. The final features for each strain had low dimensions and included knowledge from different perspectives, which were used to build the machine learning model for pathogenicity identification. RESULTS: The 40 signature positions were achieved by entropy screening. Mutations at position 135 of the hemagglutinin protein had the highest entropy value (1.06). After the informative features were directly generated from the 67 random forest models, the dimensions for class and probabilistic features were optimized as 4 and 3, respectively. The optimal class features had a maximum accuracy of 94.2% and a maximum Matthews correlation coefficient of 88.4%, while the optimal probabilistic features had a maximum accuracy of 94.1% and a maximum Matthews correlation coefficient of 88.2%. The optimized features outperformed the original informative features and amino acid features from individual descriptors. The sequential forward search strategy had better performance than the classical ensemble method. CONCLUSIONS: The optimized informative features had the best performance and were used to build a predictive model so as to identify the phenotype of influenza B virus with high pathogenicity and provide early risk warning for disease control.


Subject(s)
Amino Acids , Influenza B virus , Algorithms , Amino Acids/genetics , Influenza B virus/genetics , Machine Learning , Virulence
2.
Euro Surveill ; 27(15)2022 04.
Article in English | MEDLINE | ID: covidwho-1869326

ABSTRACT

In the WHO European Region, COVID-19 non-pharmaceutical interventions continued slowing influenza circulation in the 2021/22 season, with reduced characterisation data. A(H3) predominated and, in some countries, co-circulated with A(H1)pdm09 and B/Victoria viruses. No B/Yamagata virus detections were confirmed. Substantial proportions of characterised circulating virus subtypes or lineages differed antigenically from their respective northern hemisphere vaccine components. Appropriate levels of influenza virus characterisations should be maintained until the season end and in future seasons, when surveillance is adapted to integrate SARS-CoV-2.


Subject(s)
COVID-19 , Influenza Vaccines , Influenza, Human , Humans , Influenza A Virus, H3N2 Subtype/genetics , Influenza B virus/genetics , Influenza, Human/epidemiology , Influenza, Human/prevention & control , SARS-CoV-2 , Seasons , World Health Organization
3.
Pathology ; 54(4): 466-471, 2022 Jun.
Article in English | MEDLINE | ID: covidwho-1799763

ABSTRACT

During the COVID-19 pandemic, sample pooling has proven an effective strategy to overcome the limitations of reagent shortages and expand laboratory testing capacity. The inclusion of influenza and respiratory syncytial virus (RSV) in a multiplex tandem PCR platform with SARS-CoV-2 provides useful diagnostic and infection control information. This study aimed to evaluate the performance of the influenza and RSV targets in the AusDiagnostics SARS-CoV-2, Influenza and RSV 8-well assay, including the effect of pooling samples on target detection. RSV target detection in clinical samples was compared to the Cepheid Xpert Xpress Flu/RSV assay as a reference standard. Samples were then tested in pools of four and detection rates were compared. Owing to the unavailability of clinical samples for influenza, only the effect of sample pooling on simulated samples was evaluated for these targets. RSV was detected in neat clinical samples with a positive percent agreement (PPA) of 100% and negative percent agreement (NPA) of 99.5% compared to the reference standard, demonstrating 99.7% agreement. This study demonstrates that sample pooling by four increases the average Ct value by 2.24, 2.29, 2.20 and 1.91 cycles for the target's influenza A, influenza A typing, influenza B and RSV, respectively. The commercial AusDiagnostics SARS-CoV-2, Influenza and RSV 8-well assay was able to detect influenza and RSV at an intermediate concentration within the limit of detection of the assay. Further studies to explore the applicability of sample pooling at the lower limit of detection of the assay is needed. Nevertheless, sample pooling has shown to be a viable strategy to increase testing throughput and reduce reagent usage. In addition, the multiplexed platform targeting various respiratory viruses assists with public health and infection control responses, clinical care, and patient management.


Subject(s)
COVID-19 , Influenza A virus , Influenza, Human , Respiratory Syncytial Virus Infections , Respiratory Syncytial Virus, Human , COVID-19/diagnosis , Humans , Influenza A virus/genetics , Influenza B virus/genetics , Influenza, Human/diagnosis , Molecular Diagnostic Techniques , Nasopharynx , Pandemics , Respiratory Syncytial Virus Infections/diagnosis , Respiratory Syncytial Virus, Human/genetics , SARS-CoV-2 , Sensitivity and Specificity
4.
J Korean Med Sci ; 36(48): e328, 2021 Dec 13.
Article in English | MEDLINE | ID: covidwho-1572278

ABSTRACT

BACKGROUND: In the coronavirus disease 2019 (COVID-19) pandemic era, the simultaneous detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza virus (Flu), and respiratory syncytial virus (RSV) is important in the rapid differential diagnosis in patients with respiratory symptoms. Three multiplex real-time reverse transcription polymerase chain reaction (rRT-PCR) assays have been recently developed commercially in Korea: PowerChek™ SARS-CoV-2, Influenza A&B Multiplex Real-time PCR Kit (PowerChek; KogeneBiotech); STANDARD™ M Flu/SARS-CoV-2 Real-time Detection Kit (STANDARD M; SD BioSensor); and Allplex™ SARS-CoV-2/FluA/FluB/RSV Assay (Allplex; Seegene). We evaluated the analytical and clinical performances of these kits. METHODS: A limit of detection tests were performed and cross-reactivity analysis was executed using clinical respiratory samples. Ninety-seven SARS-CoV-2-positive, 201 SARS-CoV-2-negative, 71 influenza A-positive, 50 influenza B-positive, 78 RSV-positive, and 207 other respiratory virus-positive nasopharyngeal swabs were tested using the three assays. The AdvanSure™ respiratory viruses rRT-PCR assay (AdvanSure; LG Life Sciences) was used as a comparator assay for RSV. RESULTS: Except in influenza B, in SARS-CoV-2 and influenza A, there were no significant differences in detecting specific genes of the viruses among the three assays. All three kits did not cross-react with common respiratory viruses. All three kits had greater than 92% positive percent agreement and negative percent agreement and ≥ 0.95 kappa value in the detection of SARS-CoV-2 and flu A/B. Allplex detected RSV more sensitively than AdvanSure. CONCLUSION: The overall performance of three multiplex rRT-PCR assays for the concurrent detection of SARS-CoV-2, influenza A/B, and RSV was comparable. These kits will promote prompt differential diagnosis of COVID-19, influenza, and RSV infection in the COVID-19 pandemic era.


Subject(s)
COVID-19/diagnosis , Influenza, Human/diagnosis , Multiplex Polymerase Chain Reaction/methods , Nasopharynx/virology , RNA, Viral/analysis , Respiratory Syncytial Virus Infections/diagnosis , COVID-19/virology , Cross Reactions , Humans , Influenza A virus/genetics , Influenza A virus/isolation & purification , Influenza B virus/genetics , Influenza B virus/isolation & purification , Influenza, Human/virology , Limit of Detection , Nucleocapsid Proteins/genetics , Polyproteins/genetics , RNA, Viral/metabolism , Reagent Kits, Diagnostic , Republic of Korea , Respiratory Syncytial Virus Infections/virology , Respiratory Syncytial Virus, Human/genetics , Respiratory Syncytial Virus, Human/isolation & purification , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , Viral Matrix Proteins/genetics , Viral Proteins/genetics
5.
PLoS One ; 16(12): e0260947, 2021.
Article in English | MEDLINE | ID: covidwho-1556896

ABSTRACT

BACKGROUND: On 9th January 2020, China CDC reported a novel coronavirus (later named SARS-CoV-2) as the causative agent of the coronavirus disease 2019 (COVID-19). Identifying the first appearance of virus is of epidemiological importance to tracking and mapping the spread of SARS-CoV-2 in a country. We therefore conducted a retrospective observational study to detect SARS-CoV-2 in oropharyngeal samples collected from hospitalized patients with a Severe Acute Respiratory Infection (SARI) enrolled in the DRIVE (Development of Robust and Innovative Vaccine Effectiveness) study in five Italian hospitals (CIRI-IT BIVE hospitals network) (1st November 2019 - 29th February 2020). OBJECTIVES: To acquire new information on the real trend in SARS-CoV-2 infection during pandemic phase I and to determine the possible early appearance of the virus in Italy. MATERIALS AND METHODS: Samples were tested for influenza [RT-PCR assay (A/H1N1, A/H3N2, B/Yam, B/Vic)] in accordance with the DRIVE study protocol. Subsequently, swabs underwent molecular testing for SARS-COV-2. [one-step real-time multiplex retro-transcription (RT) PCR]. RESULTS: In the 1683 samples collected, no evidence of SARS-CoV-2 was found. Moreover, 28.3% (477/1683) of swabs were positive for influenza viruses, the majority being type A (358 vs 119 type B). A/H3N2 was predominant among influenza A viruses (55%); among influenza B viruses, B/Victoria was prevalent. The highest influenza incidence rate was reported in patients aged 0-17 years (40.3%) followed by those aged 18-64 years (24.4%) and ≥65 years (14.8%). CONCLUSIONS: In Italy, some studies have shown the early circulation of SARS-CoV-2 in northern regions, those most severely affected during phase I of the pandemic. In central and southern regions, by contrast no early circulation of the virus was registered. These results are in line with ours. These findings highlight the need to continue to carry out retrospective studies, in order to understand the epidemiology of the novel coronavirus, to better identify the clinical characteristics of COVID-19 in comparison with other acute respiratory illnesses (ARI), and to evaluate the real burden of COVID-19 on the healthcare system.


Subject(s)
Influenza, Human/epidemiology , Severe Acute Respiratory Syndrome/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , COVID-19/diagnosis , COVID-19/virology , Female , Hospitals , Humans , Influenza A Virus, H1N1 Subtype/genetics , Influenza A Virus, H1N1 Subtype/isolation & purification , Influenza A Virus, H3N2 Subtype/genetics , Influenza A Virus, H3N2 Subtype/isolation & purification , Influenza B virus/genetics , Influenza B virus/isolation & purification , Influenza, Human/pathology , Influenza, Human/virology , Italy/epidemiology , Male , Middle Aged , RNA, Viral/genetics , RNA, Viral/metabolism , Retrospective Studies , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , Severe Acute Respiratory Syndrome/pathology , Severe Acute Respiratory Syndrome/virology , Young Adult
6.
Diagn Microbiol Infect Dis ; 102(2): 115575, 2022 Feb.
Article in English | MEDLINE | ID: covidwho-1536508

ABSTRACT

COVID-19 symptomology may overlap with other circulating respiratory viruses that may also cause severe disease and for which there are specific and potentially life-saving treatments. The Abbott Alinity m Resp-4-Plex assay is a multiplex PCR assay that simultaneously detects and differentiates infection with SARS-CoV-2, influenza A, influenza B, and respiratory syncytial virus (RSV). We characterized its accuracy, precision, and analytical sensitivity. All were found to be robust for measures examined. In the context of sample-to-answer, near random access automation on the Alinity m platform, we believe that the Resp-4-Plex assay offers significant utility in addressing the current needs of the SARS-CoV-2 pandemic and future needs during anticipated endemic circulation of SARS-CoV-2 with other respiratory viruses.


Subject(s)
COVID-19/diagnosis , Influenza, Human/diagnosis , Molecular Diagnostic Techniques , Respiratory Syncytial Virus Infections/diagnosis , Female , Humans , Influenza A virus/genetics , Influenza B virus/genetics , Limit of Detection , Male , Middle Aged , Multiplex Polymerase Chain Reaction , Nucleic Acid Amplification Techniques , Respiratory Syncytial Virus, Human/genetics , SARS-CoV-2/genetics , Sensitivity and Specificity
7.
PLoS One ; 16(11): e0258798, 2021.
Article in English | MEDLINE | ID: covidwho-1515477

ABSTRACT

Two main mechanisms contribute to the continuous evolution of influenza viruses: accumulation of mutations in the hemagglutinin and neuraminidase genes (antigenic drift) and genetic re-assortments (antigenic shift). Epidemiological surveillance is important in identifying new genetic variants of influenza viruses with potentially increased pathogenicity and transmissibility. In order to characterize the 2019/20 influenza epidemic in Romania, 1042 respiratory samples were collected from consecutive patients hospitalized with acute respiratory infections in the National Institute for Infectious Diseases "Prof. Dr. Matei Balș", Bucharest Romania and tested for influenza A virus, influenza B virus and respiratory syncytial virus (RSV) by real-time PCR. Out of them, 516 cases were positive for influenza, with relatively equal distribution of influenza A and B. Two patients had influenza A and B co-infection and 8 patients had influenza-RSV co-infection. The most severe cases, requiring supplemental oxygen administration or intensive care, and the most deaths were reported in patients aged 65 years and over. Subtyping showed the predominance of A(H3N2) compared to A(H1N1)pdm09 pdm09 (60.4% and 39.6% of all subtyped influenza A isolates, respectively), and the circulation of Victoria B lineage only. Influenza B started to circulate first (week 47/2019), with influenza A appearing slightly later (week 50/2019), followed by continued co-circulation of A and B viruses throughout the season. Sixty-eight samples, selected to cover the entire influenza season and all circulating viral types, were analysed by next generation sequencing (NGS). All A(H1N1)pdm09 sequences identified during this season in Romania were clustered in the 6b1.A clade (sub-clades: 6b1.A.183P -5a and 6b1.A.187A). For most A(H1N1)pdm09 sequences, the dominant epitope was Sb (pepitope = 0.25), reducing the vaccine efficacy by approximately 60%. According to phylogenetic analysis, influenza A(H3N2) strains circulating in this season belonged predominantly to clade 3C.3A, with only few sequences in clade 3C.2A1b. These 3C.2A1b sequences, two of which belonged to vaccinated patients, harbored mutations in antigenic sites leading to potential reduction of vaccine efficacy. Phylogenetic analysis of influenza B, lineage Victoria, sequences showed that the circulating strains belonged to clade V1A3. As compared to the other viral types, fewer mutations were observed in B/Victoria strains, with limited impact on vaccine efficiency based on estimations.


Subject(s)
Epidemics , Hospitalization , Influenza A Virus, H1N1 Subtype/genetics , Influenza A Virus, H3N2 Subtype/genetics , Influenza B virus/genetics , Influenza, Human/epidemiology , Influenza, Human/history , Respiratory Syncytial Virus Infections/epidemiology , Respiratory Syncytial Virus Infections/history , Respiratory Syncytial Viruses/genetics , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Coinfection , Female , History, 21st Century , Humans , Infant , Infant, Newborn , Influenza Vaccines/therapeutic use , Influenza, Human/prevention & control , Influenza, Human/virology , Male , Middle Aged , Phylogeny , RNA, Viral/genetics , Respiratory Syncytial Virus Infections/virology , Romania/epidemiology , Young Adult
8.
Influenza Other Respir Viruses ; 14(5): 530-540, 2020 09.
Article in English | MEDLINE | ID: covidwho-1452864

ABSTRACT

BACKGROUND: Influenza is an acute infection affecting all age groups; however, elderly patients are at an increased risk. We aim to describe the clinical characteristics and the circulation of influenza virus types in elderly patients admitted for severe acute respiratory infection (SARI) to a tertiary care hospital in Bucharest, Romania, part of the I-MOVE+ hospital network. METHODS: We conducted an active surveillance study at the National Institute for Infectious Diseases "Prof. Dr Matei Balș," Bucharest, Romania, during three consecutive influenza seasons: 2015/16, 2016/17, and 2017/18. All patients aged 65 and older admitted to our hospital for SARI were tested for influenza by PCR. RESULTS: A total of 349 eligible patients were tested during the study period, and 149 (42.7%) were confirmed with influenza. Most patients, 321 (92.5%) presented at least one underlying condition at the time of hospital admission, the most frequent being cardiovascular disease, 270 (78.3%). The main influenza viral subtype circulating in 2015/16 was A(H1N1)pdm09, followed by A(H3N2) in 2016/17 and B influenza in 2017/18. Case fatality was highest in the 2015/16 season (3.7%), 0% in 2016/17, and 1.0% in 2017/18. Vaccination coverage in elderly patients with SARI from our study population was 22 (6.3%) over the three seasons. CONCLUSIONS: Our study has highlighted a high burden of comorbidities in elderly patients presenting with SARI during winter season in Romania. The influenza vaccine coverage rate needs to be substantially increased in the elderly population, through targeted interventions.


Subject(s)
Influenza, Human/epidemiology , Sentinel Surveillance , Age Factors , Aged , Aged, 80 and over , Female , Hospitalization/statistics & numerical data , Humans , Influenza A Virus, H1N1 Subtype/genetics , Influenza A Virus, H1N1 Subtype/immunology , Influenza A Virus, H3N2 Subtype/genetics , Influenza A Virus, H3N2 Subtype/immunology , Influenza B virus/genetics , Influenza B virus/immunology , Influenza Vaccines/immunology , Male , Romania/epidemiology , Seasons , Tertiary Healthcare
9.
J Virol Methods ; 298: 114304, 2021 12.
Article in English | MEDLINE | ID: covidwho-1440233

ABSTRACT

The potential co-circulation of SARS-CoV-2, influenza, and respiratory syncytial virus (RSV) could pose an unprecedented challenge to healthcare systems worldwide. Here, we compared the performance of the PowerChek SARS-CoV-2, Influenza A&B, RSV Multiplex Real-time PCR Kit (PowerChek) for simultaneous detection of SARS-CoV-2, influenza A and B, and respiratory syncytial virus with that of BioFire Respiratory Panel 2.1 (RP2.1) using 175 nasopharyngeal swab (NPS) specimens. Positive percent agreement and negative percent agreement of the PowerChek assay compared to RP2.1 were as follows: 100 % (40/40) and 100 % (135/135) for SARS-CoV-2; 100 % (39/39) and 100 % (136/136) for influenza A; 100 % (35/35) and 100 % (140/140) for influenza B; and 93.1 % (27/29) and 100 % (146/146) for RSV, respectively. The limit of detection (LOD) was accessed using RNA standards for each virus, and the LOD values of the PowerChek assay for SARS-CoV-2, influenza A and B, and RSV were 0.36, 1.24, 0.09, and 0.63 copies/µL, respectively. Our results demonstrate that the PowerChek assay is sensitive and accurate for detection of SARS-CoV-2, influenza A and B, and RSV, suggesting that this assay can be a valuable diagnostic tool when SARS-CoV-2, influenza, and RSV are co-circulating.


Subject(s)
COVID-19 , Influenza, Human , Respiratory Syncytial Virus Infections , Respiratory Syncytial Virus, Human , Humans , Influenza B virus/genetics , Influenza, Human/diagnosis , Nasopharynx , Real-Time Polymerase Chain Reaction , Respiratory Syncytial Virus Infections/diagnosis , Respiratory Syncytial Virus, Human/genetics , SARS-CoV-2 , Sensitivity and Specificity
10.
Emerg Infect Dis ; 27(7): 1821-1830, 2021.
Article in English | MEDLINE | ID: covidwho-1278363

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in late 2019, and the outbreak rapidly evolved into the current coronavirus disease pandemic. SARS-CoV-2 is a respiratory virus that causes symptoms similar to those caused by influenza A and B viruses. On July 2, 2020, the US Food and Drug Administration granted emergency use authorization for in vitro diagnostic use of the Influenza SARS-CoV-2 Multiplex Assay. This assay detects influenza A virus at 102.0, influenza B virus at 102.2, and SARS-CoV-2 at 100.3 50% tissue culture or egg infectious dose, or as few as 5 RNA copies/reaction. The simultaneous detection and differentiation of these 3 major pathogens increases overall testing capacity, conserves resources, identifies co-infections, and enables efficient surveillance of influenza viruses and SARS-CoV-2.


Subject(s)
COVID-19 , Influenza A virus , Humans , Influenza A virus/genetics , Influenza B virus/genetics , Multiplex Polymerase Chain Reaction , Reverse Transcription , SARS-CoV-2
11.
J Med Virol ; 93(7): 4392-4398, 2021 07.
Article in English | MEDLINE | ID: covidwho-1263103

ABSTRACT

With the arrival of coronavirus disease 2019 (COVID-19) in Brazil in February 2020, several preventive measures were taken by the population aiming to avoid severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection including the use of masks, social distancing, and frequent hand washing then, these measures may have contributed to preventing infection also by other respiratory viruses. Our goal was to determine the frequencies of Influenza A and B viruses (FLUAV/FLUBV), human mastadenovirus C (HAdV-C), Enterovirus 68 (EV-68), and rhinovirus (RV) besides SARS-CoV-2 among hospitalized patients suspect of COVID-19 with cases of acute respiratory disease syndrome (ARDS) in the period of March to December 2020 and to detect possible coinfections among them. Nucleic acid detection was performed using reverse-transcription quantitative polymerase chain reaction (RT-qPCR) in respiratory samples using naso-oropharyngeal swabs and bronchoalveolar lavage. A total of 418 samples of the 987 analyzed (42.3%) were positive for SARS-CoV-2, 16 (1.62%) samples were positive for FLUAV, no sample was positive for FLUBV or EV-68, 67 (6.78%) samples were positive for HAdV-C, 55 samples were positive for RV 1/2 (26.3%) and 37 for RV 2/2 (13.6%). Coinfections were also detected, including a triple coinfection with SARS-CoV-2, FLUAV, and HAdV-C. In the present work, a very low frequency of FLUV was reported among hospitalized patients with ARDS compared to the past years, probably due to preventive measures taken to avoid COVID-19 and the high influenza vaccination coverage in the region in which this study was performed.


Subject(s)
Adenoviridae Infections/epidemiology , COVID-19/epidemiology , Common Cold/epidemiology , Enterovirus Infections/epidemiology , Influenza, Human/epidemiology , Physical Distancing , Adenoviridae Infections/prevention & control , Adolescent , Adult , Aged , Aged, 80 and over , Brazil/epidemiology , COVID-19/prevention & control , Child , Child, Preschool , Coinfection/epidemiology , Coinfection/virology , Common Cold/prevention & control , Enterovirus D, Human/genetics , Enterovirus D, Human/isolation & purification , Enterovirus Infections/prevention & control , Female , Humans , Infant , Influenza A virus/genetics , Influenza A virus/isolation & purification , Influenza B virus/genetics , Influenza B virus/isolation & purification , Influenza, Human/prevention & control , Male , Masks , Mastadenovirus/genetics , Mastadenovirus/isolation & purification , Middle Aged , Nucleic Acid Amplification Techniques/methods , Reverse Transcriptase Polymerase Chain Reaction/methods , Rhinovirus/genetics , Rhinovirus/isolation & purification , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , Young Adult
12.
J Virol Methods ; 293: 114151, 2021 07.
Article in English | MEDLINE | ID: covidwho-1174407

ABSTRACT

In the current pandemic of coronavirus disease (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the co-circulation of SARS-CoV-2 and other respiratory viruses during the upcoming fall and winter seasons may present an unprecedented burden of respiratory disease in the population. Important respiratory viruses that will need to be closely monitored during this time include SARS-CoV-2, influenza A and influenza B. The epidemiology of these viruses is very similar in terms of susceptible populations, mode of transmission, and the clinical syndromes, thus the etiological agent will be difficult to differentiate without target specific assays. The availability of a sensitive and specific multiplex assay that can simultaneously detect all these targets will be valuable. Here we report the validation of a real-time reverse transciptase-PCR assay for the simultaneous detection of SARS-CoV-2, influenza A and influenza B. This multiplex assay is comparable to its singleplex counterparts with a limit-of-detection being less than 5 copies/reaction, 100 % specificity, over seven logs of dynamic range, less than 1 % coefficientof variation showing high precision, and equivalent accuracy using patient samples. It also offers the added benefits of savings in reagents and technologist time while improving testing efficiency and turn-around-times in order to respond effectively to the ongoing pandemic.


Subject(s)
COVID-19 Nucleic Acid Testing/methods , COVID-19/diagnosis , Influenza A virus/genetics , Influenza B virus/genetics , Influenza, Human/diagnosis , Multiplex Polymerase Chain Reaction/methods , SARS-CoV-2/genetics , Coinfection/diagnosis , Humans , Reproducibility of Results , Sensitivity and Specificity
13.
J Infect Chemother ; 27(6): 820-825, 2021 Jun.
Article in English | MEDLINE | ID: covidwho-1045151

ABSTRACT

INTRODUCTION: Digital immunoassays (DIAs) and molecular point-of-care (POC) tests for influenza were recently developed. We aimed to evaluate and compare the positive rate with molecular POC tests and DIAs in detecting influenza virus A, B and respiratory syncytial virus (RSV). METHODS: A prospective observational study was conducted in 2019-2020. Nasopharyngeal swab samples were collected from adult outpatients with influenza-like illness who visited four hospitals and clinics in Japan. DIAs were performed at each facility. The clinical diagnosis was determined based on the findings of DIAs, history taking, and physical assessment. Molecular POC test and reverse transcription polymerase chain reaction (RT-PCR) were performed later. RESULTS: A total of 182 patients were evaluated. The positive rate for influenza virus with molecular POC test was significantly higher than that with DIAs (51.6% versus 40.7%, p = 0.046). In patients who tested positive for influenza virus with only molecular POC test, the presence of influenza virus was confirmed by RT-PCR. In a comparison between the patients who were positive for influenza virus with only molecular POC test and those with both molecular POC test and DIA, the percentage of patients who sought consultation within 18 h after the onset of symptoms was significantly higher in the molecular POC test only group than in the both methods group (70.0% versus 43.2%, p = 0.044). CONCLUSIONS: A molecular POC test could contribute to the accurate diagnosis of influenza in patients with influenza-like illness, especially those who visited a hospital immediately after the onset of symptoms.


Subject(s)
Influenza A virus , Influenza, Human , Orthomyxoviridae , Respiratory Syncytial Virus Infections , Adult , Humans , Immunoassay , Influenza A virus/genetics , Influenza B virus/genetics , Influenza, Human/diagnosis , Japan , Orthomyxoviridae/genetics , Point-of-Care Systems , Point-of-Care Testing , Respiratory Syncytial Virus Infections/diagnosis , Sensitivity and Specificity
14.
J Clin Microbiol ; 59(4)2021 03 19.
Article in English | MEDLINE | ID: covidwho-1153640

ABSTRACT

Patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza A (flu A), influenza B (flu B), and respiratory syncytial virus (RSV) have overlapping clinical presentations, but the approaches to treatment and management of infections caused by these viruses are different. Therefore, rapid diagnosis in conjunction with infection prevention measures is important to prevent transmission of the diseases. Recently, a new Xpert Xpress SARS-CoV-2/Flu/RSV (Xpert 4-in-1) assay enables the detection and differentiation of SARS-CoV-2, flu A, flu B, and RSV in upper respiratory tract specimens. In this study, we evaluated the performance of the Xpert 4-in-1 assay by comparing it with that of the Xpert Xpress SARS-CoV-2 and Xpert Xpress Flu/RSV assays for the detection of the four viruses in nasopharyngeal (NP) specimens. A total of 279 NP specimens, including 66, 56, 64, and 53 specimens positive for SARS-CoV-2, flu A, flu B, and RSV, respectively, were included. The Xpert 4-in-1 assay demonstrated high concordance with the comparator assays, with overall agreement for SARS-CoV-2, flu A, flu B, and RSV at 99.64%, 100%, 99.64%, and 100%, respectively, and a high Cohen's kappa (κ) value ranging from 0.99 to 1.00, indicating an almost perfect correlation between assays. The cycle threshold value association between positive samples also showed a good correlation between assays. In conclusion, the overall performance of the Xpert 4-in-1 assay was highly comparable to that of the Xpert SARS-CoV-2 and Xpert Flu/RSV assays for the detection and differentiation of SARS CoV-2, flu A, flu B, and RSV in NP specimens.


Subject(s)
COVID-19 , Herpesvirus 1, Cercopithecine , Influenza A virus , Influenza, Human , Respiratory Syncytial Virus Infections , Humans , Influenza A virus/genetics , Influenza B virus/genetics , Influenza, Human/diagnosis , Molecular Diagnostic Techniques , Nasopharynx , SARS-CoV-2 , Sensitivity and Specificity
15.
J Virol ; 95(9)2021 04 12.
Article in English | MEDLINE | ID: covidwho-1102152

ABSTRACT

Current influenza vaccines, live attenuated or inactivated, do not protect against antigenically novel influenza A viruses (IAVs) of pandemic potential, which has driven interest in the development of universal influenza vaccines. Universal influenza vaccine candidates targeting highly conserved antigens of IAV nucleoprotein (NP) are promising as vaccines that induce T cell immunity, but concerns have been raised about the safety of inducing robust CD8 T cell responses in the lungs. Using a mouse model, we systematically evaluated effects of recombinant adenovirus vectors (rAd) expressing IAV NP (A/NP-rAd) or influenza B virus (IBV) NP (B/NP-rAd) on pulmonary inflammation and function after vaccination and following live IAV challenge. After A/NP-rAd or B/NP-rAd vaccination, female mice exhibited robust systemic and pulmonary vaccine-specific B cell and T cell responses and experienced no morbidity (e.g., body mass loss). Both in vivo pulmonary function testing and lung histopathology scoring revealed minimal adverse effects of intranasal rAd vaccination compared with unvaccinated mice. After IAV challenge, A/NP-rAd-vaccinated mice experienced significantly less morbidity, had lower pulmonary virus titers, and developed less pulmonary inflammation than unvaccinated or B/NP-rAd-vaccinated mice. Based on analysis of pulmonary physiology using detailed testing not previously applied to the question of T cell damage, mice protected by vaccination also had better lung function than controls. Results provide evidence that, in this model, adenoviral universal influenza vaccine does not damage pulmonary tissue. In addition, adaptive immunity, in particular, T cell immunity in the lungs, does not cause damage when restimulated but instead mitigates pulmonary damage following IAV infection.IMPORTANCE Respiratory viruses can emerge and spread rapidly before vaccines are available. It would be a tremendous advance to use vaccines that protect against whole categories of viruses, such as universal influenza vaccines, without the need to predict which virus will emerge. The nucleoprotein (NP) of influenza virus provides a target conserved among strains and is a dominant T cell target. In animals, vaccination to NP generates powerful T cell immunity and long-lasting protection against diverse influenza strains. Concerns have been raised, but not evaluated experimentally, that potent local T cell responses might damage the lungs. We analyzed lung function in detail in the setting of such a vaccination. Despite CD8 T cell responses in the lungs, lungs were not damaged and functioned normally after vaccination alone and were protected upon subsequent infection. This precedent provides important support for vaccines based on T cell-mediated protection, currently being considered for both influenza and SARS-CoV-2 vaccines.


Subject(s)
Adenoviridae , Genetic Vectors , Influenza B virus , Influenza Vaccines , Lung , Orthomyxoviridae Infections , Adenoviridae/genetics , Adenoviridae/immunology , Animals , B-Lymphocytes/immunology , B-Lymphocytes/pathology , Disease Models, Animal , Female , Genetic Vectors/genetics , Genetic Vectors/immunology , Immunity, Cellular , Influenza B virus/genetics , Influenza B virus/immunology , Influenza Vaccines/genetics , Influenza Vaccines/immunology , Lung/immunology , Lung/pathology , Lung/virology , Mice , Orthomyxoviridae Infections/genetics , Orthomyxoviridae Infections/immunology , Orthomyxoviridae Infections/pathology , Orthomyxoviridae Infections/prevention & control , T-Lymphocytes/immunology , T-Lymphocytes/pathology
16.
Biotechniques ; 70(3): 167-174, 2021 03.
Article in English | MEDLINE | ID: covidwho-1063262

ABSTRACT

The ongoing pandemic has demonstrated the utility of widespread surveillance and diagnostic detection of the novel SARS-CoV-2. Reverse-transcription loop-mediated isothermal amplification (RT-LAMP) has enabled broader testing, but current LAMP tests only detect single targets and require separate reactions for controls. With flu season in the Northern Hemisphere, the ability to screen for multiple targets will be increasingly important, and the ability to include internal controls in RT-LAMP allows for improved efficiency. Here we describe multiplexed RT-LAMP with four targets (SARS-CoV-2, influenza A, influenza B, human RNA) in a single reaction using real-time and end point fluorescence detection. Such increased functionality of RT-LAMP will enable even broader adoption of this molecular testing approach and aid in the fight against this public health threat.


Subject(s)
Influenza A virus/genetics , Influenza B virus/genetics , Molecular Diagnostic Techniques/methods , Nucleic Acid Amplification Techniques/methods , RNA, Viral/genetics , SARS-CoV-2/genetics , COVID-19 Nucleic Acid Testing/methods , DNA Primers/genetics , Fluorescence , RNA, Viral/analysis , Reverse Transcription , Sensitivity and Specificity
18.
J Med Microbiol ; 70(2)2021 Feb.
Article in English | MEDLINE | ID: covidwho-1010700

ABSTRACT

Introduction. Laboratories worldwide are facing high demand for molecular testing during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, which might be further aggravated by the upcoming influenza season in the northern hemisphere.Gap Statement. Given that the symptoms of influenza are largely indistinguishable from those of coronavirus disease 2019 (COVID-19), both SARS-CoV-2 and the influenza viruses require concurrent testing by RT-PCR in patients presenting with symptoms of respiratory tract infection.Aim. We adapted and evaluated a laboratory-developed multiplex RT-PCR assay for simultaneous detection of SARS-CoV-2 (dual target), influenza A and influenza B (SC2/InflA/InflB-UCT) on a fully automated high-throughput system (cobas6800).Methodology. Analytical performance was assessed by serial dilution of quantified reference material and cell culture stocks in transport medium, including pretreatment for chemical inactivation. For clinical evaluation, residual portions of 164 predetermined patient samples containing SARS-CoV-2 (n=52), influenza A (n=43) or influenza B (n=19), as well as a set of negative samples, were subjected to the novel multiplex assay.Results. The assay demonstrated comparable analytical performance to currently available commercial tests, with limits of detection of 94.9 cp ml-1 for SARS-CoV-2, 14.6 cp ml-1 for influenza A and 422.3 cp ml-1 for influenza B. Clinical evaluation showed excellent agreement with the comparator assays (sensitivity of 98.1, 97.7 and 100 % for Sars-CoV-2 and influenza A and B, respectively).Conclusion. The SC2/InflA/InflB-UCT allows for efficient high-throughput testing for all three pathogens and thus provides streamlined diagnostics while conserving resources during the influenza season.


Subject(s)
COVID-19 Testing/methods , COVID-19/diagnosis , Influenza A virus/genetics , Influenza B virus/genetics , Influenza, Human/diagnosis , SARS-CoV-2/genetics , High-Throughput Screening Assays/methods , Humans , Influenza A virus/isolation & purification , Influenza B virus/isolation & purification , Influenza, Human/virology , Limit of Detection , Molecular Diagnostic Techniques/methods , Multiplex Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , SARS-CoV-2/isolation & purification , Sensitivity and Specificity
19.
Euro Surveill ; 25(46)2020 11.
Article in English | MEDLINE | ID: covidwho-937369

ABSTRACT

The COVID-19 pandemic negatively impacted the 2019/20 WHO European Region influenza surveillance. Compared with previous 4-year averages, antigenic and genetic characterisations decreased by 17% (3,140 vs 2,601) and 24% (4,474 vs 3,403). Of subtyped influenza A viruses, 56% (26,477/47,357) were A(H1)pdm09, 44% (20,880/47,357) A(H3). Of characterised B viruses, 98% (4,585/4,679) were B/Victoria. Considerable numbers of viruses antigenically differed from northern hemisphere vaccine components. In 2020/21, maintaining influenza virological surveillance, while supporting SARS-CoV-2 surveillance is crucial.


Subject(s)
Coronavirus Infections/epidemiology , Disease Notification/statistics & numerical data , Epidemiological Monitoring , Influenza A virus/isolation & purification , Influenza B virus/isolation & purification , Influenza, Human/epidemiology , Influenza, Human/virology , Antigens, Viral/genetics , Betacoronavirus , COVID-19 , Humans , Influenza A Virus, H1N1 Subtype/genetics , Influenza A Virus, H1N1 Subtype/isolation & purification , Influenza A Virus, H3N2 Subtype/genetics , Influenza A Virus, H3N2 Subtype/isolation & purification , Influenza A virus/genetics , Influenza B virus/genetics , Pandemics , Pneumonia, Viral , Population Surveillance , RNA, Viral/genetics , SARS-CoV-2 , Sequence Analysis, DNA
20.
Exp Biol Med (Maywood) ; 246(4): 400-405, 2021 02.
Article in English | MEDLINE | ID: covidwho-913987

ABSTRACT

Due to the common symptoms of COVID-19, patients are similar to influenza-like illness. Therefore, the detection method would be crucial to discriminate between SARS-CoV-2 and influenza virus-infected patients. In this study, CRISPR-Cas12a-based detection was applied for detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza A virus, and influenza B virus which would be a practical and attractive application for screening of patients with COVID-19 and influenza in areas with limited resources. The limit of detection for SARS-CoV-2, influenza A, and influenza B detection was 10, 103, and 103 copies/reaction, respectively. Moreover, the assays yielded no cross-reactivity against other respiratory viruses. The results revealed that the detection of influenza virus and SARS-CoV-2 by using RT-RPA and CRISPR-Cas12a technology reaches 96.23% sensitivity and 100% specificity for SARS-CoV-2 detection. The sensitivity for influenza virus A and B detections was 85.07% and 94.87%, respectively. In addition, the specificity for influenza virus A and B detections was approximately 96%. In conclusion, the RT-RPA with CRISPR-Cas12a assay was an effective method for the screening of influenza viruses and SARS-CoV-2 which could be applied to detect other infectious diseases in the future.


Subject(s)
COVID-19/diagnosis , Influenza A virus/genetics , Influenza B virus/genetics , Influenza, Human/diagnosis , Molecular Diagnostic Techniques , Nucleic Acid Amplification Techniques , SARS-CoV-2/genetics , CRISPR-Cas Systems , Clustered Regularly Interspaced Short Palindromic Repeats , Humans , Influenza A virus/isolation & purification , Influenza B virus/isolation & purification , Limit of Detection , RNA, Viral/analysis , RNA, Viral/genetics , SARS-CoV-2/isolation & purification
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