scholarly journals EFFECT OF SODIUM MONOFLUOROACETATE ON THE MULTIPLICATION OF INFLUENZA VIRUSES, MUMPS VIRUS, AND PNEUMONIA VIRUS OF MICE (PVM)

1952 ◽  
Vol 96 (6) ◽  
pp. 531-548 ◽  
Author(s):  
William J. Mogabgab ◽  
Frank L. Horsfall
Keyword(s):  
Chick Embryo ◽  
Influenza A ◽  
Virus Titer ◽  
Mumps Virus ◽  
Influenza Viruses ◽  
Mouse Lung ◽  
Influenza B Virus ◽  
Influenza B ◽  
Chick Embryos ◽  
And Control

Sodium fluoroacetate, given after virus inoculation in doses of 3 to 4 mg. per kg. in mice or 2 mg. in chick embryos, caused only a slight delay in the multiplication of the PR8 strain of influenza A virus in the mouse lung and of PR8 or the Lee strain of influenza B virus in the allantoic sac. The quantities of the compound used were sufficient to cause approximately 10 to 20 per cent mortality in mice and 100 per cent in chick embryos. The use of small virus inocula did not markedly increase the effect of sodium fluoroacetate on the multiplication of PR8 or Lee in the chick embryo and maximal titers were obtained in all cases. In contrast to the findings in the chick embryo, sodium fluoroacetate caused a definite delay in the multiplication of Lee virus in the mouse lung but did not affect the final virus titer. Sodium fluoroacetate in like amounts caused only a minimal delay in the multiplication of pneumonia virus of mice (PVM) in the mouse lung or of mumps virus in the chick embryo. With both PVM and mumps virus, maximal titers were obtained almost simultaneously in fluoroacetate and control animals. When three daily injections of the compound were given to mice infected previously with PVM, a definite diminution in the virus titer was demonstrable. However, pretreatment with three daily injections of the compound caused no alteration in the capacity of mice to support the multiplication of PVM. From the results of these experiments, it appears that the cellular metabolic processes blocked by sodium fluoroacetate are not essential for the multiplication of influenza viruses, mumps virus, or pneumonia virus of mice (PVM).

scholarly journals INTERFERENCE BETWEEN THE INFLUENZA VIRUSES

1944 ◽  
Vol 79 (4) ◽  
pp. 379-400 ◽  
Author(s):  
James E. Ziegler ◽  
George I. Lavin ◽  
Frank L. Horsfall
Keyword(s):  
Chick Embryo ◽  
Ultraviolet Radiation ◽  
Influenza A ◽  
Influenza Viruses ◽  
Influenza B Virus ◽  
Influenza B ◽  
Interference Phenomenon ◽  
B Virus ◽  
Virus System

Influenza A or influenza B virus rendered non-infective by ultraviolet radiation was found to be capable of producing interference with the multiplication of active influenza viruses in the chick embryo. Certain temporal and quantitative relationships affecting the interference phenomenon with this host-virus system were studied. An hypothesis of the mechanism of interference between the influenza viruses is proposed and discussed.

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 Haemagglutination-inhibition antibodies against influenza A and influenza B in maternal and neonatal sera

1978 ◽  
Vol 80 (1) ◽  
pp. 13-19 ◽  
Author(s):  
N. Masurel ◽  
J. I. de Bruijne ◽  
H. A. Beuningh ◽  
H. J. A. Schouten
Keyword(s):  
Influenza Virus ◽  
Maternal Age ◽  
Influenza A ◽  
Haemagglutination Inhibition ◽  
Influenza Viruses ◽  
Influenza B Virus ◽  
Influenza B ◽  
B Virus ◽  
Duration Of Pregnancy ◽  
Pregnancy And Birth

SUMMARYHaemagglutination inhibition (HI) antibodies against the influenza viruses A/Hong Kong/8/68 (H3N2) and B/Nederland/77/66 were determined in 420 paired sera from mothers and newborns (umbilical cord sera), sampled in 1970–1.A higher concentration of antibodies against influenza A virus was found more frequently in neonatal than in maternal sera. By contrast, low titres against influenza B virus were more frequently observed in neonatal than in maternal sera. Maternal age, duration of pregnancy, and birth-weight did not affect the results of the tests.It is suggested that the titre of the newborn against an epidemic influenza virus can be predicted from that of the mother. Furthermore, the maternal titre may be an indication of the susceptibility of the newborn infant to influenza infections.

scholarly journals Influenza A and B viruses in the population of Vojvodina, Serbia

2014 ◽  
Vol 66 (1) ◽  
pp. 43-50 ◽  
Author(s):  
J. Radovanov ◽  
V. Milosevic ◽  
I. Hrnjakovic ◽  
V. Petrovic ◽  
M. Ristic ◽  
...  
Keyword(s):  
Influenza A ◽  
Respiratory Infections ◽  
Influenza Viruses ◽  
Influenza B Virus ◽  
Nasopharyngeal Swab ◽  
Influenza B ◽  
Influenza A Viruses ◽  
B Virus ◽  
Life Threatening ◽  
Seasonal Epidemic

At present, two influenza A viruses, H1N1pdm09 and H3N2, along with influenza B virus co-circulate in the human population, causing endemic and seasonal epidemic acute febrile respiratory infections, sometimes with life-threatening complications. Detection of influenza viruses in nasopharyngeal swab samples was done by real-time RT-PCR. There were 60.2% (53/88) positive samples in 2010/11, 63.4% (52/82) in 2011/12, and 49.9% (184/369) in 2012/13. Among the positive patients, influenza A viruses were predominant during the first two seasons, while influenza B type was more active during 2012/13. Subtyping of influenza A positive samples revealed the presence of A (H1N1)pdm09 in 2010/11, A (H3N2) in 2011/12, while in 2012/13, both subtypes were detected. The highest seroprevalence against influenza A was in the age-group 30-64, and against influenza B in adults aged 30-64 and >65.

scholarly journals Non-Uniform and Non-Random Binding of Nucleoprotein to Influenza A and B Viral RNA

Viruses ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 522 ◽  
Author(s):  
Valerie Le Sage ◽  
Adalena Nanni ◽  
Amar Bhagwat ◽  
Dan Snyder ◽  
Vaughn Cooper ◽  
...  
Keyword(s):  
Influenza A ◽  
Gene Segment ◽  
Influenza Viruses ◽  
Viral Rna ◽  
Influenza B Virus ◽  
Viral Gene ◽  
Influenza B ◽  
Influenza A Viruses ◽  
Binding Profile ◽  
Random Manner

The genomes of influenza A and B viruses have eight, single-stranded RNA segments that exist in the form of a viral ribonucleoprotein complex in association with nucleoprotein (NP) and an RNA-dependent RNA polymerase complex. We previously used high-throughput RNA sequencing coupled with crosslinking immunoprecipitation (HITS-CLIP) to examine where NP binds to the viral RNA (vRNA) and demonstrated for two H1N1 strains that NP binds vRNA in a non-uniform, non-random manner. In this study, we expand on those initial observations and describe the NP-vRNA binding profile for a seasonal H3N2 and influenza B virus. We show that, similar to H1N1 strains, NP binds vRNA in a non-uniform and non-random manner. Each viral gene segment has a unique NP binding profile with areas that are enriched for NP association as well as free of NP-binding. Interestingly, NP-vRNA binding profiles have some conservation between influenza A viruses, H1N1 and H3N2, but no correlation was observed between influenza A and B viruses. Our study demonstrates the conserved nature of non-uniform NP binding within influenza viruses. Mapping of the NP-bound vRNA segments provides information on the flexible NP regions that may be involved in facilitating assembly.

scholarly journals Detection of severe acute respiratory syndrome coronavirus 2 and influenza viruses based on CRISPR-Cas12a

2020 ◽  
pp. 153537022096379
Author(s):  
Oraphan Mayuramart ◽  
Pattaraporn Nimsamer ◽  
Somruthai Rattanaburi ◽  
Naphat Chantaravisoot ◽  
Kritsada Khongnomnan ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Severe Acute Respiratory Syndrome ◽  
Influenza A ◽  
Limit Of Detection ◽  
Cross Reactivity ◽  
Influenza Viruses ◽  
Influenza B Virus ◽  
Influenza B ◽  
Influenza Virus A ◽  
B Virus

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.

scholarly journals CONCURRENT INFECTION WITH INFLUENZA VIRUS AND MUMPS VIRUS OR PNEUMONIA VIRUS OF MICE (PVM) AS BEARING ON THE INHIBITION OF VIRUS MULTIPLICATION BY BACTERIAL POLYSACCHARIDES

1949 ◽  
Vol 89 (1) ◽  
pp. 37-52 ◽  
Author(s):  
Harold S. Ginsberg ◽  
Frank L. Horsfall
Keyword(s):  
Influenza A ◽  
Virus Multiplication ◽  
Mumps Virus ◽  
Influenza Viruses ◽  
Influenza B ◽  
Capsular Polysaccharides ◽  
Concurrent Infection ◽  
Mechanism Of Inhibition ◽  
Metabolic Systems ◽  
Differing Effect

Preexisting infection with PVM or mumps virus does not prevent multiplication of the virus of influenza A or B in the same tissue. Similarly, pre-existing infection with one or another of the influenza viruses does not prevent multiplication of either PVM or mumps virus in the same tissue. The failure of these two groups of viruses to interfere with the multiplication of each other is discussed in relation to the mechanism of inhibition of multiplication of mumps virus and PVM by the capsular polysaccharides of Friedländer bacilli, and the ability of influenza A and influenza B viruses to multiply in the presence of large quantities of these carbohydrates. It is suggested that differences in the requirements of the two groups of viruses for host cell metabolic systems may serve to explain both the lack of interference between them and the differing effect of polysaccharides upon their multiplication.

scholarly journals STUDIES ON THE MECHANISM OF ADAPTATION OF INFLUENZA VIRUS TO MICE

1947 ◽  
Vol 86 (5) ◽  
pp. 357-366 ◽  
Author(s):  
George K. Hirst
Keyword(s):  
Influenza A Virus ◽  
Influenza A ◽  
High Titer ◽  
Strain Difference ◽  
Mouse Lung ◽  
Influenza B Virus ◽  
Influenza B ◽  
Difference Problem ◽  
B Virus ◽  
Repeated Passage

1. When strains of influenza A virus which have been isolated in chick embryos are introduced into the mouse lung, the virus multiplies readily and achieves initially a titer which is as high as is even obtained, even after repeated passage. The high initial titer of virus may be unaccompanied by any lethal or visible pathogenic effects; but with four or five mouse passages the agent becomes lethal in high titer and causes extensive pulmonary consolidation, though its capacity to multiply in the lung has not increased. In one example the adaptation to mouse lung was accompanied by increasing capacity to agglutinate guinea pig red cells without a corresponding increase in agglutinating power for chicken cells. Influenza B virus, in preliminary tests, did not behave in a similar fashion. 2. The adaptation of influenza A virus to mice is accompanied by changes in antigenic pattern, as detected by cross-tests with the agglutination inhibition method. Two strains, initially similar, with passage, changed in pattern along divergent paths so that they became not only unlike the parent strains but unlike each other. This finding has important implications for the interpretation of the strain difference problem in human influenza.

scholarly journals Bacterial Sinusitis and Otitis Media following Influenza Virus Infection in Ferrets

2006 ◽  
Vol 74 (5) ◽  
pp. 2562-2567 ◽  
Author(s):  
Ville T. Peltola ◽  
Kelli L. Boyd ◽  
Julie L. McAuley ◽  
Jerold E. Rehg ◽  
Jonathan A. McCullers
Keyword(s):  
Influenza Virus ◽  
Otitis Media ◽  
Influenza A ◽  
Bacterial Colonization ◽  
Influenza Virus Infection ◽  
Influenza Viruses ◽  
Influenza B Virus ◽  
Influenza B ◽  
Complication Rates ◽  
Pneumococcal Infections

ABSTRACT Streptococcus pneumoniae is the leading cause of otitis media, sinusitis, and pneumonia. Many of these infections result from antecedent influenza virus infections. In this study we sought to determine whether the frequency and character of secondary pneumococcal infections differed depending on the strain of influenza virus that preceded bacterial challenge. In young ferrets infected with influenza virus and then challenged with pneumococcus, influenza viruses of any subtype increased bacterial colonization of the nasopharynx. Nine out of 10 ferrets infected with H3N2 subtype influenza A viruses developed either sinusitis or otitis media, while only 1 out of 11 ferrets infected with either an H1N1 influenza A virus or an influenza B virus did so. These data may partially explain why bacterial complication rates are higher during seasons when H3N2 viruses predominate. This animal model will be useful for further study of the mechanisms that underlie viral-bacterial synergism.

scholarly journals Impact of oseltamivir treatment on influenza A and B dynamics in human volunteers

2020 ◽  
Author(s):  
Kyla L. Hooker ◽  
Vitaly V. Ganusov
Keyword(s):  
Clinical Trials ◽  
Influenza Virus ◽  
Influenza A ◽  
Influenza Viruses ◽  
Influenza B Virus ◽  
Influenza B ◽  
Virus Shedding ◽  
Viral Shedding ◽  
Human Volunteers ◽  
The Impact

AbstractInfluenza viruses infect millions of humans every year causing an estimated 400,000 deaths globally. Due to continuous virus evolution current vaccines provide only limited protection against the flu. Several antiviral drugs are available to treat influenza infection, and one of the most most commonly used drugs is oseltamivir (Tamiflu). While the mechanism of action of oseltamivir as a neuraminidase inhibitor is well understood, the impact of oseltamivir on influenza virus dynamics in humans has been controversial. Many clinical trials with oseltamivir have been done by pharmaceutical companies such as Roche but the results of these trials until recently have been reported as summary reports or papers. Typically, such reports included median virus shedding curves for placebo and drug-treated influenza virus infected volunteers often indicating high efficacy of the early treatment. However, median shedding curves may be not accurately representing drug impact in individual volunteers. Importantly, due to public pressure clinical trials data testing oseltamivir efficacy has been recently released in the form of redacted PDF documents. We digitized and re-analyzed experimental data on influenza virus shedding in human volunteers from three previously published trials: on influenza A (1 trial) or B viruses (2 trials). Given that not all volunteers exposed to influenza viruses actually start virus shedding we found that impact of oseltamivir on the virus shedding dynamics was dependent on i) selection of volunteers that were infected with the virus, and ii) the detection limit in the measurement assay; both of these details were not well articulated in the published studies. By assuming that any viral measurement is above the limit of detection we could match previously published data on median influenza A virus (flu A study) shedding but not on influenza B virus shedding (flu B study B) in human volunteers. Additional analyses confirmed that oseltamivir had an impact on the duration of shedding and overall shedding (defined as area under the curve) but this result was varied by the trial. Interestingly, treatment had no impact on the rates at which shedding increased or declined with time in individual volunteers. Additional analyses showed that oseltamivir impacted the kinetics of the start and end of viral shedding and in about 20-40% of volunteers treatment had no impact on viral shedding duration. Our results suggest an unusual impact of oseltamivir on influenza viruses shedding kinetics and caution about the use of published median data or data from a few individuals for inferences. Furthermore, we call for the need to publish raw data from critical clinical trials that can be then independently analyzed.

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