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Influenza A H5N1 (Avian Flu) HA ELISA Kit Species

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[#CSB-E17980] Influenza A H5N1 (Avian Flu) HA ELISA Kit Species


CSB-E17980 | Influenza A H5N1 (Avian Flu) HA ELISA Kit Species, 96T
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Pubmed ID :29900780
Publication Date : //
  An outbreak of HPAIV H5N1 in Nakhon Sawan province, Thailand, in 2004 caused sporadic deaths of Asian openbill storks ( Anastomus oscitans). An investigation was undertaken to determine if this virus occurs and circulates in wild birds in Nakhon Sawan province. Following the outbreak, a widespread serosurvey was conducted using the hemagglutination inhibition assay and microneutralization assay to detect antibodies against AIV H5. From 2007 to 2014, blood was collected from a total of 753 wild birds, representing 10 orders and 44 species. The results reveal that 10 serum samples were positive for AIV H5 antibodies. These seropositive results, found in the orders Ciconiiformes and Anseriformes, demonstrate that waterfowl serve as a reservoir host of AIV. Moreover, the seroprevalences in streak-eared bulbul showed habitat sharing with waterfowl or duck.

Authors : Poltep Kanaporn, Ketchim Natthaphat, Paungpin Weena, Prompiram Phirom, Sedwisai Poonyapat, Chamsai Tatiyanuch, Puthavathana Pilaipan, Ratanakorn Parntep,

(2) A dual motif in the hemagglutinin of H5N1 Goose/Guangdong-like HPAIV is conserved from their early evolution and increases both membrane fusion pH and virulence.[TOP]

Pubmed ID :29899102
Publication Date : //
Zoonotic highly pathogenic avian influenza viruses (HPAIV) have raised serious public health concerns of a novel pandemic. These strains emerge from low-pathogenic precursors by acquisition of a polybasic hemagglutinin (HA) cleavage site, the prime virulence determinant. However, required co-adaptations of the HA early in HPAIV evolution remained uncertain. To address this question, we generated several HA1/HA2 chimeras and point mutants of an H5N1 clade 2.2.2 HPAIV and an H5N1 low-pathogenic strain. Initial surveys of 3385 HPAIV H5 HA sequences revealed frequencies of 0.5% for the single amino acids 123R or 124I each, in dual combination however at 97.5%. This highly conserved dual motif is still retained in contemporary H5 HPAIV including the novel H5NX reassortants carrying neuraminidases of different subtypes like the H5N8 and the zoonotic H5N6 strains. Remarkably, the earliest Asian H5N1 HPAIV, the Goose/Guangdong strains from 1996/97 carried 123R only, whereas 124I appeared later in 1997. Experimental reversion in the HPAIV HA to the two residues 123S/124T, characteristic in low-pathogenic strains, prevented virus rescue while the single substitutions attenuated the virus both in chicken and mice considerably, accompanied by a decreased HA fusion pH. This increased pH sensitivity of H5 HPAIV enables HA-mediated membrane fusion at a higher endosomal pH. Therefore, this HA adaptation may permit infection of cells with less acidic endosomes, e.g. within the respiratory tract, resulting in an extended organ tropism. Taken together, HA co-adaptation to increased acid sensitivity promoted early evolution of H5 Goose/Guangdong-like HPAIV and is still required for their zoonotic potential. Zoonotic highly pathogenic avian influenza viruses (HPAIV) have raised serious public health concerns of a novel pandemic. Their prime virulence determinant is the polybasic hemagglutinin (HA) cleavage site. However, required co-adaptations in the HA (and other genes) remained uncertain. Here, we identified the dual motif 123R/124I in the HA head that increases the activation pH of HA-mediated membrane fusion, essential for virus genome release into the cytoplasm. This motif is extremely predominant in H5 HPAIV and emerged already in the earliest 1997 H5N1 HPAIV. Reversion to 123S or 124T, characteristic in low-pathogenic strains, attenuated the virus in chicken and mice, accompanied by a decreased HA activation pH. This increased pH sensitivity of H5 HPAIV extends the viral tropism to cells with less acidic endosomes, e.g. within the respiratory tract. Therefore, early HA adaptation to increased acid sensitivity promoted emergence of H5 Goose/Guangdong-like HPAIV and is required for their zoonotic potential.

Authors : Wessels Ute, Abdelwhab El-Sayed M, Veits Jutta, Hoffmann Donata, Mamerow Svenja, Stech Olga, Hellert Jan, Beer Martin, Mettenleiter Thomas C, Stech Jürgen,

(3) Broadly-reactive human monoclonal antibodies elicited following pandemic H1N1 influenza virus exposure protect mice from highly pathogenic H5N1 challenge.[TOP]

Pubmed ID :29899095
Publication Date : //
Broadly cross-reactive antibodies that recognize conserved epitopes within the influenza virus hemagglutinin (HA) stalk domain are of particular interest for their potential use as therapeutic and prophylactic agents against multiple influenza virus subtypes including zoonotic virus strains. Here, we characterized four human HA stalk-reactive monoclonal antibodies (mAbs) for their binding breadth and affinity, neutralization capacity, and protective potential against an highly pathogenic avian influenza virus. The monoclonal antibodies were isolated from individuals shortly following infection with (70-1F02 and 1009-3B05) or vaccination against (05-2G02 and 09-3A01) A(H1N1)pdm09. Three of the mAbs bound HAs from multiple strains of group 1 viruses, and one mAb, 05-2G02, bound to both group 1 and group 2 influenza A HAs. All four antibodies prophylactically protected mice against a lethal challenge with the highly pathogenic A/Vietnam/1203/04 (H5N1) strain. Two mAbs, 70-1F02 and 09-3A01, were further tested for their therapeutic efficacy against the same strain and showed good efficacy in this setting as well. One mAb, 70-1F02, was co-crystallized with H5 HA and showed similar heavy chain only interactions as a the previously described anti-stalk antibody CR6261. Finally, we showed that antibodies that compete with these mAbs are prevalent in serum from an individual recently infected with A(H1N1)pdm09 virus. The antibodies described here can be developed into broad-spectrum antiviral therapeutics that could be used to combat infections with zoonotic or emerging pandemic influenza viruses. The rise in zoonotic infections of humans with emerging influenza viruses is a worldwide public health concern. The majority of recent zoonotic human influenza cases were caused by H7N9 and H5Nx viruses and were associated with high morbidity and mortality. In addition, seasonal influenza viruses are estimated to cause up to 650,000 deaths annually worldwide. Currently available anti-viral treatment options include only neuraminidase inhibitors, but some influenza viruses are naturally resistant to these drugs, and others quickly develop resistance-conferring mutations. Alternative therapeutics are urgently needed. Broadly protective antibodies that target the conserved 'stalk' domain of the hemagglutinin represent potential potent antiviral prophylactic and therapeutic agents that can assist pandemic preparedness. Here, we describe four human monoclonal antibodies that target conserved regions of influenza HA and characterize their binding spectrum, as well as their protective capacity in prophylactic and therapeutic settings against a lethal challenge with a zoonotic influenza virus.

Authors : Nachbagauer Raffael, Shore David, Yang Hua, Johnson Scott K, Gabbard Jon D, Tompkins S Mark, Wrammert Jens, Wilson Patrick C, Stevens James, Ahmed Rafi, Krammer Florian, Ellebedy Ali H,

(4) Mitigation strategies to reduce the generation and transmission of airborne highly pathogenic avian influenza virus particles during processing of infected poultry.[TOP]

Pubmed ID :29891217
Publication Date : //
Airborne transmission of H5N1 highly pathogenic avian influenza (HPAI) viruses has occurred among poultry and from poultry to humans during home or live-poultry market slaughter of infected poultry, and such transmission has been experimentally reproduced. In this study, we investigated simple, practical changes in the processing of H5N1 virus-infected chickens to reduce infectious airborne particles and their transmission. Our findings suggest that containing the birds during the killing and bleeding first step by using a disposable plastic bag, a commonly available cooking pot widely used in Egypt (halla), or a bucket significantly reduces generation of infectious airborne particles and transmission to ferrets. Similarly, lack of infectious airborne particles was observed when processing vaccinated chickens that had been challenged with HPAI virus. Moreover, the use of a mechanical defeatherer significantly increased total number of particles in the air compared to manual defeathering. This study confirms that simple changes in poultry processing can efficiently mitigate generation of infectious airborne particles and their transmission to humans.

Authors : Bertran Kateri, Clark Andrew, Swayne David E,

(5) Exploring contacts facilitating transmission of influenza A(H5N1) virus between poultry farms in West Java, Indonesia: A major role for backyard farms?[TOP]

Pubmed ID :29891149
Publication Date : //
Highly pathogenic avian influenza virus (HPAIV) H5N1 has been reported in Asia, including Indonesia since 2003. Although several risk factors related to the HPAIV outbreaks in poultry in Indonesia have been identified, little is known of the contact structure of farms of different poultry production types (backyard chickens, broilers, layers, and ducks). This study aims to quantify the contact rates associated with the movement of people, and movements of live birds and products and equipment that affect the risk of HPAIV H5N1 transmission between poultry farms in Indonesia. On 124 poultry farms in 6 districts in West Java, logbooks were distributed to record the movements of farmers/staff and visitors and their poultry contacts. Most movements in backyard chicken, commercial native chicken, broiler and duck farms were visits to and from other poultry farms, whilst in layer farms visits to and from poultry companies, visits to egg collection houses and visit from other poultry farms were most frequent. Over 75% of persons visiting backyard chicken and duck farms had previously visited other poultry farms on the same day. Visitors of backyard chicken farms had the highest average contact rate, either direct contact with poultry on other farms before the visits (1.35 contact/day) or contact during their visits in the farms (10.03 contact/day). These results suggest that backyard chicken farms are most at risk for transmission of HPAIV compared to farms of the other poultry production types. Since visits of farm-to-farm were high, backyard farms could also a potential source for HPAIV transmission to commercial poultry farms.

Authors : Wibawa Hendra, Karo-Karo Desniwaty, Pribadi Eko Sugeng, Bouma Annemarie, Bodewes Rogier, Vernooij Hans, Diyantoro , Sugama Agus, Muljono David H, Koch Guus, Tjatur Rasa Fadjar Sumping, Stegeman Arjan,

(6) Pandemic Avian Influenza and Intra/Interhaemagglutinin Subtype Electrostatic Variation among Viruses Isolated from Avian, Mammalian, and Human Hosts.[TOP]

Pubmed ID :29888260
Publication Date : //
Host jump can result in deadly pandemic events when avian influenza A viruses broaden their host specificity and become able to infect mammals, including humans. Haemagglutinin-the major capsid protein in influenza A viruses-is subjected to high rate mutations, of which several occur at its "head": the receptor-binding domain that mediates specific binding to host cell receptors. Such surface-changing mutations may lead to antigenically novel influenza A viruses hence in pandemics by host jump and in vaccine escape by antigenic drift. Changes in haemagglutinin surface electrostatics have been recently associated with antigenic drift and with clades evolution and spreading in H5N1 and H9N2 viruses. We performed a comparative analysis of haemagglutinin surface electrostatics to investigate clustering and eventual fingerprints among representative pandemic (H5 and H7) and nonpandemic (H4 and H6) avian influenza viral subtypes. We observed preferential sorting of viruses isolated from mammalian/human hosts among these electrostatic clusters of a subtype; however, sorting was not "100% specific" to the different clusters. Therefore, electrostatic fingerprints can help in understanding, but they cannot explain alone the host jumping mechanism.

Authors : Righetto Irene, Filippini Francesco,

(7) [Comparison of epidemiological characteristics of human infection with avian influenza A (H5N1) virus in five countries of Asia and Africa].[TOP]

Pubmed ID :29886690
Publication Date : //
To understand characteristics of demographic, seasonal and spatial distribution of H5N1 cases in major countries of Asia (Indonesia, Cambodia, Vietnam, China) and Africa (Egypt). Through searching public data resource and published papers, we collected cases information in five countries from May 1st, 1997 to November 6th, 2017, including general characteristics, diagnosis, onset and exposure history, etc. Different characteristics of survived and death cases in different countries were described and χ(2) test was used to compare the differences among death cases and odds ratio () and 95 value was used to compare death risk in different countries. A total of 856 cases were reported in five countries with Egypt had the most cases (44.3%). The highest number of cases were reported in 2015 (18.3%). 53% cases were reported from January to March, and 96.1% of cases had the history of poultry exposure. 64.2% (43 cases) cases in China had live poultry market exposure, but the sick/dead poultry exposure was the major exposure for cases in other four countries. 452 death cases were reported in five countries, and the fatality rate was 52.8%. With Egypt as the reference group, the highest death risk was seen in Indonesia ( (95): 11.52 (7.46-17.77)), followed by Cambodia ( (95): 4.27(2.37-7.69)) and China ( (95): 2.87 (1.73-4.74)). The age distribution of death cases among 5 countries was statistically significant, and the highest fatality rate was in 15-54 years group in Egypt (83.6%, 102 cases), while in Cambodia the highest fatality rate was in 0-14 years group (76.9%, 30 cases). The highest number of deaths were reported in 2006, and 48.3% were reported from January to March. There was difference in exposure routes among 5 countries (χ(2)=43.85, 0.001), 63.2% (24 cases) of the death cases in China had live poultry market exposure. 92.9% (79 cases), 83.3% (40 cases) and 100.0% (38 cases) death cases in Indonesia, Vietnam and Camodia had sick/dead poultry exposure, respectively;and 81.6% (31 cases) of the death cases in Egypt had backyard poultry exposure. The geographical distribution, seasonal age, gender, exposure matter and outcome of H5N1 cases in five countries were different.

Authors : Jiang H, Qin Y, Zheng J D, Peng Z B, Feng L Z, Wang W, Lai S J, Yu H J,

(8) Multi-clade H5N1 virus-like particles: Immunogenicity and protection against H5N1 virus and effects of beta-propiolactone.[TOP]

Pubmed ID :29885769
Publication Date : //
During the past decade, H5N1 highly pathogenic avian influenza (HPAI) viruses have diversified genetically and antigenically, suggesting the need for multiple H5N1 vaccines. However, preparation of multiple vaccines from live H5N1 HPAI viruses is difficult and economically not feasible representing a challenge for pandemic preparedness. Here we evaluated a novel multi-clade recombinant H5N1 virus-like particle (VLP) design, in which H5 hemagglutinins (HA) and N1 neuraminidase (NA) derived from four distinct clades of H5N1 virus were co-localized within the VLP structure. The multi-clade H5N1 VLPs were prepared by using a recombinant baculovirus expression system and evaluated for functional hemagglutination and neuraminidase enzyme activities, particle size and morphology, as well as for the presence of baculovirus in the purified VLP preparations. To remove residual baculovirus, VLP preparations were treated with beta-propiolactone (BPL). Immunogenicity and efficacy of multi-clade H5N1 VLPs were determined in an experimental ferret H5N1 HPAI challenge model, to ascertain the effect of BPL on immunogenicity and protective efficacy against lethal challenge. Although treatment with BPL reduced immunogenicity of VLPs, all vaccinated ferrets were protected from lethal challenge with influenza A/VietNam/1203/2004 (H5N1) HPAI virus, indicating that multi-clade VLP preparations treated with BPL represent a potential approach for pandemic preparedness vaccines.

Authors : Pushko Peter, Tretyakova Irina, Hidajat Rachmat, Sun Xiangjie, Belser Jessica A, Tumpey Terrence M,

(9) 1-Benzyl-3-cetyl-2-methylimidazolium Iodide (NH125) Is a Broad-Spectrum Inhibitor of Virus Entry with Lysosomotropic Features.[TOP]

Pubmed ID :29874821
Publication Date : //
Cellular kinases are crucial for the transcription/replication of many negative-strand RNA viruses and might serve as targets for antiviral therapy. In this study, a library comprising 80 kinase inhibitors was screened for antiviral activity against vesicular stomatitis virus (VSV), a prototype member of the family . 1-Benzyl-3-cetyl-2-methylimidazolium iodide (NH125), an inhibitor of eukaryotic elongation factor 2 (eEF2) kinase, significantly inhibited entry of single-cycle VSV encoding a luciferase reporter. Treatment of virus particles had only minimal effect on virus entry, indicating that the compound primarily acts on the host cell rather than on the virus. Accordingly, resistant mutant viruses were not detected when the virus was passaged in the presence of the drug. Unexpectedly, NH125 led to enhanced, rather than reduced, phosphorylation of eEF2, however, it did not significantly affect cellular protein synthesis. In contrast, NH125 revealed lysosomotropic features and showed structural similarity with -dodecylimidazole, a known lysosomotropic agent. Related alkylated imidazolium compounds also exhibited antiviral activity, which was critically dependent on the length of the alkyl group. Apart from VSV, NH125 inhibited infection by VSV pseudotypes containing the envelope glycoproteins of viruses that are known to enter cells in a pH-dependent manner, i.e. avian influenza virus (H5N1), Ebola virus, and Lassa virus. In conclusion, we identified an alkylated imidazolium compound which inhibited entry of several viruses not because of the previously postulated inhibition of eEF2 kinase but most likely because of its lysosomotropic properties.

Authors : Moeschler Sarah, Locher Samira, Zimmer Gert,

(10) Humoral immunity to influenza in an at-risk population and severe influenza cases in Russia in 2016-2017.[TOP]

Pubmed ID :29872951
Publication Date : //
This work aimed to analyze the herd immunity to influenza among a Russian population living in regions with an increased risk of emergence of viruses with pandemic potential, and to isolate and investigate virus strains from severe influenza cases, including fatal cases, during the 2016-2017 epidemic season. In November 2016 - March 2017 highly pathogenic influenza outbreaks were registered in Russia among wild birds and poultry. No cases of human infection were registered. Analysis of 760 sera from people who had contact with infected or perished birds revealed the presence of antibodies to A(H5N1) virus of clade and A(H5N8) virus of clade The 2016-2017 influenza epidemic season in Russia began in weeks 46-47 of 2016 with predominant circulation of influenza A(H3N2) viruses. Strains isolated from severe influenza cases mainly belonged to 3C.2a.2 and 3C.2a.3 genetic groups. Up to the 8th week of 2017 severe influenza cases were often caused by influenza B viruses which belonged to 1A genetic group with antigenic properties similar to B/Brisbane/60/2008. All influenza A and B virus strains isolated in the 2016-2017 epidemic season were sensitive to oseltamivir and zanamivir.

Authors : Ilyicheva Tatyana N, Durymanov Alexander G, Svyatchenko Svetlana V, Marchenko Vasily Yu, Sobolev Ivan A, Bakulina Anastasiya Yu, Goncharova Natalia I, Kolosova Natalia P, Susloparov Ivan M, Pyankova Olga G, Ryzhikov Alexander B, Maksyutov Rinat A,