scholarly journals Methods for Molecular Surveillance of Influenza Used in Macedonia

PRILOZI ◽  
2014 ◽  
Vol 35 (2) ◽  
pp. 25-30
Author(s):  
Golubinka Bosevska ◽  
Elizabeta Janceska ◽  
Gordana Kuzmanovska ◽  
Vladimir Mikik ◽  
Nikola Panovski
Keyword(s):  
Influenza Virus ◽  
Predictive Value ◽  
Influenza A ◽  
Rna Extraction ◽  
Influenza Virus Infection ◽  
Laboratory Diagnosis ◽  
Influenza Viruses ◽  
Rt Pcr ◽  
Two Samples ◽  
Nose And Throat

AbstractThe aim: To present and compare different Nucleic Acid Testing assays used for laboratory diagnosis of influenza virus infection in our country.Materials and methods: Respiratory samples used were nose and throat swabs. The RNA extraction was performed with a QIAamp viral RNA kit. During the season 2009–2010 the first 25 samples were tested with: conventional gel-based RT-PCR and CDC rtRT-PCR using published specific matrix and HA gene primers and probes for influenza virus typing and subtyping.Results: Of 25 samples tested with conventional RT-PCR7(28%) were positive for influenza A, but negative for A/H1seasonal and A/H3. Retested with rtRT-PCR 9(36%) were positive for influenza A, 8(32%) were positive for A/H1pdm and 1(4%) was A/H3. Two samples positive with rtRT-PCR for influenza A were negative with RT-PCR. The sensitivity of the RT-PCR in comparison with rtRT-PCR is 100% and the specificity is 88.89%. Positive predictive value for RT-PCR is 77.78%, and negative predictive value is 100%. RT-PCR is a four-step and rtRT-PCR a one-step procedure. The turn-around time of RT-PCR is 6 hours and for rtRT-PCR it is 2 hours.Discussion and conclusion: For surveillance purposes nose and throat swabs are the more easy and practical to collect. It was proved that RT-PCR is too laborious, multi-step and time-consuming. The sensitivity of both assays is equal. The specificity of rtRT-PCR is higher. NAT assays for detection of influenza viruses have become an integral component of the surveillance programme in our country. They provide a fast, accurate and sensitive detection of influenza.

scholarly journals Emergence of H7N9 Influenza A Virus Resistant to Neuraminidase Inhibitors in Nonhuman Primates

2015 ◽  
Vol 59 (8) ◽  
pp. 4962-4973 ◽  
Author(s):  
Yasushi Itoh ◽  
Shintaro Shichinohe ◽  
Misako Nakayama ◽  
Manabu Igarashi ◽  
Akihiro Ishii ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Influenza A ◽  
Cynomolgus Macaque ◽  
Influenza Virus Infection ◽  
Influenza Viruses ◽  
H7n9 Virus ◽  
Macaque Model ◽  
H7n9 Influenza Virus ◽  
Number Of Patients ◽  
H7n9 Influenza

ABSTRACTThe number of patients infected with H7N9 influenza virus has been increasing since 2013. We examined the efficacy of neuraminidase (NA) inhibitors and the efficacy of a vaccine against an H7N9 influenza virus, A/Anhui/1/2013 (H7N9), isolated from a patient in a cynomolgus macaque model. NA inhibitors (oseltamivir and peramivir) barely reduced the total virus amount because of the emergence of resistant variants with R289K or I219T in NA [residues 289 and 219 in N9 of A/Anhui/1/2013 (H7N9) correspond to 292 and 222 in N2, respectively] in three of the six treated macaques, whereas subcutaneous immunization of an inactivated vaccine derived from A/duck/Mongolia/119/2008 (H7N9) prevented propagation of A/Anhui/1/2013 (H7N9) in all vaccinated macaques. The percentage of macaques in which variant H7N9 viruses with low sensitivity to the NA inhibitors were detected was much higher than that of macaques in which variant H5N1 highly pathogenic influenza virus was detected after treatment with one of the NA inhibitors in our previous study. The virus with R289K in NA was reported in samples from human patients, whereas that with I219T in NA was identified for the first time in this study using macaques, though no variant H7N9 virus was reported in previous studies using mice. Therefore, the macaque model enables prediction of the frequency of emerging H7N9 virus resistant to NA inhibitorsin vivo. Since H7N9 strains resistant to NA inhibitors might easily emerge compared to other influenza viruses, monitoring of the emergence of variants is required during treatment of H7N9 influenza virus infection with NA inhibitors.

scholarly journals Phase III Randomized, Double-Blind Study Comparing Single-Dose Intravenous Peramivir with Oral Oseltamivir in Patients with Seasonal Influenza Virus Infection

2011 ◽  
Vol 55 (11) ◽  
pp. 5267-5276 ◽  
Author(s):  
Shigeru Kohno ◽  
Muh-Yong Yen ◽  
Hee-Jin Cheong ◽  
Nobuo Hirotsu ◽  
Tadashi Ishida ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Virus Infection ◽  
Influenza A ◽  
Seasonal Influenza ◽  
Influenza Virus Infection ◽  
Influenza Viruses ◽  
Phase Iii ◽  
Controlled Study ◽  
Double Blind Study ◽  
Double Blind

ABSTRACTAntiviral medications with activity against influenza viruses are important in controlling influenza. We compared intravenous peramivir, a potent neuraminidase inhibitor, with oseltamivir in patients with seasonal influenza virus infection. In a multinational, multicenter, double-blind, double-dummy randomized controlled study, patients aged ≥20 years with influenza A or B virus infection were randomly assigned to receive either a single intravenous infusion of peramivir (300 or 600 mg) or oral administration of oseltamivir (75 mg twice a day [b.i.d.] for 5 days). To demonstrate the noninferiority of peramivir in reducing the time to alleviation of influenza symptoms with hazard model analysis and a noninferiority margin of 0.170, we planned to recruit 1,050 patients in South Korea, Japan, and Taiwan. A total of 1,091 patients (364 receiving 300 mg and 362 receiving 600 mg of peramivir; 365 receiving oseltamivir) were included in the intent-to-treat infected population. The median durations of influenza symptoms were 78.0, 81.0, and 81.8 h in the groups treated with 300 mg of peramivir, 600 mg of peramivir, and oseltamivir, respectively. The hazard ratios of the 300- and 600-mg-peramivir groups compared to the oseltamivir group were 0.946 (97.5% confidence interval [CI], 0.793, 1.129) and 0.970 (97.5% CI, 0.814, 1.157), respectively. Both peramivir groups were noninferior to the oseltamivir group (97.5% CI, <1.170). The overall incidence of adverse drug reactions was significantly lower in the 300-mg-peramivir group, but the incidence of severe reactions in either peramivir group was not different from that in the oseltamivir group. Thus, a single intravenous dose of peramivir may be an alternative to a 5-day oral dose of oseltamivir for patients with seasonal influenza virus infection.

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 Reemerging H5N1 Influenza Viruses in Hong Kong in 2002 Are Highly Pathogenic to Ducks

2004 ◽  
Vol 78 (9) ◽  
pp. 4892-4901 ◽  
Author(s):  
Katharine M. Sturm-Ramirez ◽  
Trevor Ellis ◽  
Barry Bousfield ◽  
Lucy Bissett ◽  
Kitman Dyrting ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Hong Kong ◽  
Influenza A ◽  
Influenza Virus Infection ◽  
Influenza Viruses ◽  
Neurological Dysfunction ◽  
Aquatic Birds ◽  
Antigenic Analysis ◽  
Highly Pathogenic ◽  
H5n1 Influenza

ABSTRACT Waterfowl are the natural reservoir of all influenza A viruses, which are usually nonpathogenic in wild aquatic birds. However, in late 2002, outbreaks of highly pathogenic H5N1 influenza virus caused deaths among wild migratory birds and resident waterfowl, including ducks, in two Hong Kong parks. In February 2003, an avian H5N1 virus closely related to one of these viruses was isolated from two humans with acute respiratory distress, one of whom died. Antigenic analysis of the new avian isolates showed a reactivity pattern different from that of H5N1 viruses isolated in 1997 and 2001. This finding suggests that significant antigenic variation has recently occurred among H5N1 viruses. We inoculated mallards with antigenically different H5N1 influenza viruses isolated between 1997 and 2003. The new 2002 avian isolates caused systemic infection in the ducks, with high virus titers and pathology in multiple organs, particularly the brain. Ducks developed acute disease, including severe neurological dysfunction and death. Virus was also isolated at high titers from the birds' drinking water and from contact birds, demonstrating efficient transmission. In contrast, H5N1 isolates from 1997 and 2001 were not consistently transmitted efficiently among ducks and did not cause significant disease. Despite a high level of genomic homology, the human isolate showed striking biological differences from its avian homologue in a duck model. This is the first reported case of lethal influenza virus infection in wild aquatic birds since 1961.

scholarly journals Prevalence of Antibodies against Seasonal Influenza A and B Viruses in Children in Netherlands

2011 ◽  
Vol 18 (3) ◽  
pp. 469-476 ◽  
Author(s):  
R. Bodewes ◽  
G. de Mutsert ◽  
F. R. M. van der Klis ◽  
M. Ventresca ◽  
S. Wilks ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Influenza A ◽  
Influenza Virus Infection ◽  
Population Based ◽  
Influenza Viruses ◽  
Serum Samples ◽  
Cross Sectional ◽  
Population Based Study ◽  
Influenza A H1n1 ◽  
First Time

ABSTRACTTo gain insight into the age at which children become infected with influenza viruses for the first time, we analyzed the seroprevalence of antibodies against influenza viruses in children 0 to 7 years of age in the Netherlands. Serum samples were collected during a cross-sectional population-based study in 2006 and 2007 and were tested for the presence of antibodies against influenza A/H1N1, A/H3N2, and B viruses representative of viruses present in previous influenza seasons using the hemagglutination inhibition assay. The seroprevalence of antibodies to influenza virus was higher in children 1 to 6 months of age than in children 7 to 12 months of age, which likely reflects the presence of maternally derived antibodies. The proportion of study subjects >1 year of age with detectable antibodies against influenza viruses gradually increased with age until they reached the age of 6 years, when they all had antibodies to at least one influenza A virus. These findings may have implications for the development of vaccination strategies aiming at the protection of young children against seasonal and/or pandemic influenza virus infection.

scholarly journals Discovery of Allopregnanolone Against Influenza Virus With Broad Spectrum in Vitro

2021 ◽  
Author(s):  
yuqi Wang ◽  
Yanyan Wang ◽  
Hong Cao
Keyword(s):  
Natural Products ◽  
Influenza Virus ◽  
Viral Replication ◽  
Broad Spectrum ◽  
Influenza A ◽  
Influenza Virus Infection ◽  
Influenza Viruses ◽  
Wild Type Virus ◽  
Dependent Manner ◽  
Viral Yield

Abstract Background: Influenza virus infection with seasonal or occasional but devastating morbidity and mortality, is a severe threat to public health. The frequent emergence of resistant viral strains limited application of current antivirals and posing an urgent need for novel antiviral therapies. Natural products offered a broad prospect in the screening and development of new influenza inhibitors.Methods: In this research, a high-throughput antiviral screening for 891 natural products was performed based on a recombinant reporter influenza A virus. According to the cytotoxicity assay and dose-response relationship, alloprogesterone (ALLO), as the positive hit was selected, and verified by viral titer reduction assay and immunofluorescence using a wild-type virus. Followingly, we explored its antiviral potency of counteracting with IAV and IBV, and preliminary investigated the mechanism of ALLO through time-of-addition assay and mini-replicon system.Results: Under the criteria of 80% inhibition and 70% cell viability, ALLO was screened out and confirmed antiviral activity in varied cells. The inhibitory effect of ALLO against influenza virus with a dose-dependent manner and significantly reduced viral yield of five different influenza viruses in the presence of 40 µM ALLO, including oseltamivir-resistant virus. Moreover, ALLO exhibited no influence on IAV entry or release during the viral replication cycle, but obviously interfered with the genome replication regarding post-infection 2 hrs to 6 hrs, which is consistent with the evidence of decreased polymerase activity.Conclusions: In summary, we firstly identified a new pharmacological activity of ALLO, as a broad spectrum inhibitor for treatment influenza infections, targeting viral replication stage and possessing great value of further development.

scholarly journals Interferon mediated prophylactic protection against respiratory viruses conferred by a prototype live attenuated influenza virus vaccine lacking non-structural protein 1

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Raveen Rathnasinghe ◽  
Mirella Salvatore ◽  
Hongyong Zheng ◽  
Sonia Jangra ◽  
Thomas Kehrer ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Virus Vaccine ◽  
Influenza A ◽  
Influenza Virus Infection ◽  
Influenza Virus Vaccine ◽  
Influenza Viruses ◽  
Type I ◽  
Respiratory Pathogens ◽  
Structural Protein ◽  
Human Influenza Virus

AbstractThe influenza A non-structural protein 1 (NS1) is known for its ability to hinder the synthesis of type I interferon (IFN) during viral infection. Influenza viruses lacking NS1 (ΔNS1) are under clinical development as live attenuated human influenza virus vaccines and induce potent influenza virus-specific humoral and cellular adaptive immune responses. Attenuation of ΔNS1 influenza viruses is due to their high IFN inducing properties, that limit their replication in vivo. This study demonstrates that pre-treatment with a ΔNS1 virus results in an antiviral state which prevents subsequent replication of homologous and heterologous viruses, preventing disease from virus respiratory pathogens, including SARS-CoV-2. Our studies suggest that ΔNS1 influenza viruses could be used for the prophylaxis of influenza, SARS-CoV-2 and other human respiratory viral infections, and that an influenza virus vaccine based on ΔNS1 live attenuated viruses would confer broad protection against influenza virus infection from the moment of administration, first by non-specific innate immune induction, followed by specific adaptive immunity.

scholarly journals Influenza A Virus Vaccination: Immunity, Protection, and Recent Advances Toward A Universal Vaccine

Vaccines ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. 434 ◽  
Author(s):  
Christopher E. Lopez ◽  
Kevin L. Legge
Keyword(s):  
Immune Response ◽  
Influenza Virus ◽  
Virus Infection ◽  
Influenza A ◽  
Influenza Virus Infection ◽  
Influenza Viruses ◽  
Antigenic Drift ◽  
Influenza Vaccines ◽  
Virus Infections ◽  
Universal Vaccine

Influenza virus infections represent a serious public health threat and account for significant morbidity and mortality worldwide due to seasonal epidemics and periodic pandemics. Despite being an important countermeasure to combat influenza virus and being highly efficacious when matched to circulating influenza viruses, current preventative strategies of vaccination against influenza virus often provide incomplete protection due the continuous antigenic drift/shift of circulating strains of influenza virus. Prevention and control of influenza virus infection with vaccines is dependent on the host immune response induced by vaccination and the various vaccine platforms induce different components of the local and systemic immune response. This review focuses on the immune basis of current (inactivated influenza vaccines (IIV) and live attenuated influenza vaccines (LAIV)) as well as novel vaccine platforms against influenza virus. Particular emphasis will be placed on how each platform induces cross-protection against heterologous influenza viruses, as well as how this immunity compares to and contrasts from the “gold standard” of immunity generated by natural influenza virus infection.

scholarly journals Ethanol Extract of Caesalpinia decapetala Inhibits Influenza Virus Infection In Vitro and In Vivo

Viruses ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 557 ◽  
Author(s):  
Li Zhang ◽  
Jungang Chen ◽  
Chang Ke ◽  
Haiwei Zhang ◽  
Shoujun Zhang ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Influenza A ◽  
Antiviral Agents ◽  
Influenza Virus Infection ◽  
Virus Titer ◽  
Ethanol Extract ◽  
Influenza Viruses ◽  
Virus Infections

Influenza virus infections can lead to viral pneumonia and acute respiratory distress syndrome in severe cases, causing significant morbidity and mortality and posing a great threat to human health. Because of the diversity of influenza virus strains and drug resistance to the current direct antiviral agents, there have been no effective drugs as yet to cure all patients infected by influenza viruses. Natural products from plants contain compounds with diverse structures that have the potential to interact with multiple host and virus factors. In this study, we identified the ethanol extract of Caesalpinia decapetala (Roth) Alston (EEC) as an inhibitor against the replication of a panel of influenza A and B viruses both on human pulmonary epithelial A549 and human monocytic U937 cells. The animal study revealed that EEC administration reduces the weight loss and improves the survival rate of mice infected with lethal influenza virus. Also, EEC treatment attenuated lung injury and reduced virus titer significantly. In conclusion, we showed that EEC has antiviral activity both in vitro and in vivo, suggesting that the plant C. decapetala has the potential to be further developed as a resource of new anti-influenza drugs.

scholarly journals Suppressor of cytokine signaling (SOCS)5 ameliorates influenza infection via inhibition of EGFR signaling

eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Lukasz Kedzierski ◽  
Michelle D Tate ◽  
Alan C Hsu ◽  
Tatiana B Kolesnik ◽  
Edmond M Linossi ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Influenza A ◽  
Influenza Infection ◽  
Influenza Virus Infection ◽  
Growth Factor Receptor ◽  
Influenza Viruses ◽  
Cytokine Signaling ◽  
Virus Infections ◽  
Suppressor Of Cytokine Signaling ◽  
Inflammatory Conditions

Influenza virus infections have a significant impact on global human health. Individuals with suppressed immunity, or suffering from chronic inflammatory conditions such as COPD, are particularly susceptible to influenza. Here we show that suppressor of cytokine signaling (SOCS) five has a pivotal role in restricting influenza A virus in the airway epithelium, through the regulation of epidermal growth factor receptor (EGFR). Socs5-deficient mice exhibit heightened disease severity, with increased viral titres and weight loss. Socs5 levels were differentially regulated in response to distinct influenza viruses (H1N1, H3N2, H5N1 and H11N9) and were reduced in primary epithelial cells from COPD patients, again correlating with increased susceptibility to influenza. Importantly, restoration of SOCS5 levels restricted influenza virus infection, suggesting that manipulating SOCS5 expression and/or SOCS5 targets might be a novel therapeutic approach to influenza.

Sign in / Sign up

Export Citation Format

Share Document