| pathobiology of highly pathogenic avian influenza virus h5n2 infection in juvenile ostriches from south africa. | in 2011, over 35,000 ostriches were slaughtered in the oudtshoorn district of the western cape province of south africa following the diagnosis of highly pathogenic avian influenza virus h5n2. we describe the pathology and virus distribution via immunohistochemistry in juvenile birds that died rapidly in this outbreak after showing signs of depression and weakness. associated sialic acid (sa) receptor distribution in uninfected birds is also described. at necropsy, enlarged spleens, swollen live ... | 2012 | 23402120 |
| efficacy of rhvt-ai vector vaccine in broilers with passive immunity against challenge with two antigenically divergent egyptian clade 2.2.1 hpai h5n1 strains. | in countries where avian influenza has become endemic, early vaccination of layer pullets or broilers with classical inactivated vaccines at the hatchery is no longer an option because of interference with passive immunity indirectly induced by the necessary vaccination of the breeders. on the other hand, injection of thousands of chicks from 7 to 10 days old on farms has been determined to be unreliable and, therefore, poorly efficacious. for these reasons, interest has arisen regarding a newly ... | 2012 | 23402112 |
| avian influenza in north america, 2009-2011. | all reports of avian influenza virus infections in poultry and isolations from wild bird species in canada, the united states, and mexico between 2009 and 2011 involved low pathogenic avian influenza. all three countries reported outbreaks of low pathogenic notifiable avian influenza in poultry during this period. the reports involved outbreaks of h5n2 among commercial turkeys in canada in 2009 and 2010; outbreaks of h5n3 in turkeys in 2009, h5n2 in chickens in 2010, h7n3 in turkeys in 2011, and ... | 2012 | 23402102 |
| genetic analysis of avian influenza viruses: cocirculation of avian influenza viruses with allele a and b nonstructural gene in northern pintail (anas acuta) ducks wintering in japan. | the pandemic influenza virus strains of 1918 (h1n1), 1957 (h2n2), 1968 (h3n2), and 2009 (h1n1) have genes related to avian influenza viruses (aivs). the nonstructural (ns) gene of aivs plays a significant role in host-viral interaction. however, little is known about the degree of diversity of this gene in northern pintail (anas acuta) ducks wintering in japan. this study describes characteristics of pintail-originated h1n1, h1n2, h1n3, h5n2, h5n3, h5n9, and h7n7 viruses. most of the viruses wer ... | 2012 | 23320157 |
| formatted single-domain antibodies can protect mice against infection with influenza virus (h5n2). | this work continues a series of recently published studies that employ recombinant single-domain antibody (sdab, or nanobody®) generation technologies to battle viruses by a passive immunization approach. as a proof of principle, we describe a modified technique to efficiently generate protective molecules against a particular strain of influenza virus within a reasonably short period of time. this approach starts with the immunization of a camel (camelus bactrianus) with the specified antigen-e ... | 2012 | 23274623 |
| surveillance and characterization of avian influenza viruses from migratory water birds in eastern hokkaido, the northern part of japan, 2009-2010. | avian influenza virus (aiv) surveillance was conducted around a small pond in obihiro, eastern hokkaido, japan. eleven aivs were isolated from a total of 1,269 fecal samples of migratory wild birds collected during 2009 and 2010. the sample number covered approximately 60 % of the total number of birds observed during sampling periods. the subtypes of the isolates included h3n8 (4 isolates), h5n2 (3), h6n2 (2), h6n1 (1), and h11n2 (1). the h3n8 subtype was most prevalent as in the previous studi ... | 2012 | 23264106 |
| heterosubtypic protective immunity against widely divergent influenza subtypes induced by fusion protein 4sm2 in balb/c mice. | regular reformulation of currently available vaccines is necessary due to the unpredictable variability of influenza viruses. therefore, vaccine based on a highly conserved antigen with capability of induction of effective immune responses could be a potential solution. influenza matrix protein-2 (m2) is highly conserved across influenza subtypes and a promising candidate for a broadly protective influenza vaccine. for the enhancement of broad protection, four tandem copies of consensus m2 gene ... | 2014 | 24502341 |
| avian influenza rapidly induces antiviral genes in duck lung and intestine. | ducks are the natural reservoir of influenza a and survive infection by most strains. to characterize the duck immune response to influenza, we sought to identify innate immune genes expressed early in an infection. we used suppressive subtractive hybridization (ssh) to construct 3 libraries enriched in differentially expressed genes from lung rna of a duck infected with highly pathogenic avian influenza virus a/vietnam/1203/04 (h5n1), or lung and intestine rna of a duck infected with low pathog ... | 2012 | 22534314 |
| a single electroporation delivery of a dna vaccine containing the hemagglutinin gene of asian h5n1 avian influenza virus generated a protective antibody response in chickens against a north american virus strain. | protection against the avian influenza (ai) h5n1 virus is suspected to be mainly conferred by the presence of antibodies directed against the hemagglutinin (ha) protein of the virus. a single electroporation delivery of 100 or 250 μg of a dna vaccine construct, pcag-ha, carrying the ha gene of strain a/hanoi/30408/2005 (h5n1), in chickens led to the development of anti-ha antibody response in 16 of 17 immunized birds, as measured by a hemagglutination inhibition (hi) test, competitive enzyme-lin ... | 2013 | 23365205 |
| inhibition of influenza a virus infection in vitro by peptides designed in silico. | influenza a viruses are enveloped, segmented negative single-stranded rna viruses, capable of causing severe human respiratory infections. currently, only two types of drugs are used to treat influenza a infections, the m2 h(+) ion channel blockers (amantadine and rimantadine) and the neuraminidase inhibitors (nai) (oseltamivir and zanamivir). moreover, the emergence of drug-resistant influenza a virus strains has emphasized the need to develop new antiviral agents to complement or replace the e ... | 2013 | 24146939 |
| antiviral responses by swine primary bronchoepithelial cells are limited compared to human bronchoepithelial cells following influenza virus infection. | swine generate reassortant influenza viruses because they can be simultaneously infected with avian and human influenza; however, the features that restrict influenza reassortment in swine and human hosts are not fully understood. type i and iii interferons (ifns) act as the first line of defense against influenza virus infection of respiratory epithelium. to determine if human and swine have different capacities to mount an antiviral response the expression of ifn and ifn-stimulated genes (isg) ... | 2013 | 23875024 |
| prevalence and characterization of influenza viruses in diverse species in los llanos, colombia. | while much is known about the prevalence of influenza viruses in north america and eurasia, their prevalence in birds and mammals in south america is largely unknown. to fill this knowledge gap and provide a baseline for future ecology and epidemiology studies, we conducted 2 years of influenza surveillance in the eastern plains (los llanos) region of colombia. real-time reverse transcriptase polymerase chain reaction (rt-pcr) identified influenza viruses in wild birds, domestic poultry, swine a ... | 2013 | 26038461 |
| killed bacillus subtilis spores as a mucosal adjuvant for an h5n1 vaccine. | heat killed spores of the gram-positive bacterium bacillus subtilis have been evaluated as a vaccine delivery system with mucosal adjuvant properties for influenza. killed spores were able to bind h5n1 virions (nibrg-14; clade 1) and, when intra-nasally administered to mice, resulting immune responses, both humoral and cell mediated, were enhanced compared to immunization with the virion alone. levels of both systemic igg and mucosal siga specific to the virion were elevated. levels of igg2a (a ... | 2012 | 22446640 |
| consequence of cryptosporidiosis on the immune response of vaccinated broiler chickens against newcastle disease and/or avian influenza. | the consequence of cryptosporidiosis on the immune response of vaccinated chickens against newcastle disease and/or avian influenza was studied by using 240, 1 day old, male, white hy-line chicks and divided into 8 groups and subgroups. each group or subgroup was consisting of 30 chicks (15 × 2 replicates). the first and second groups were kept as unvaccinated control, g1uninfected and g2 infected. g3, g4 and g5 contained 2 subgroups a&b (g3a, g3b, g4a, g4b, g5a and g5b). chicks of subgroup a we ... | 2014 | 24993748 |
| inhibitory effects of an aqueous extract from cortex phellodendri on the growth and replication of broad-spectrum of viruses in vitro and in vivo. | cortex phellodendri (c. phellodendri), the dried trunk bark of phellodendron amurense ruprecht, has been known as a traditional herbal medicine, showing several bioactivities. however, antiviral activity of c. phellodendri aqueous extract (cp) not reported in detail, particularly aiming the prophylactic effectiveness. | 2016 | 27484768 |
| interferon-mediated antiviral activities of angelica tenuissima nakai and its active components. | angelica tenuissima nakai is a widely used commodity in traditional medicine. nevertheless, no study has been conducted on the antiviral and immune-modulatory properties of an aqueous extract of angelica tenuissima nakai. in the present study, we evaluated the antiviral activities and the mechanism of action of an aqueous extract of angelica tenuissima nakai both in vitro and in vivo. in vitro, an effective dose of angelica tenuissima nakai markedly inhibited the replication of influenza a virus ... | 2016 | 26727903 |
| the highly conserved ha2 protein of the influenza a virus induces a cross protective immune response. | existing influenza vaccines protect mostly homologous subtypes and acted most effectively only when well matched to the circulating strain. immunization with an updated vaccine is therefore necessary to maintain long-term protection and the development of a broadly protective influenza vaccine against the threat of pandemic outbreak. the highly conserved ha2 glyco-polypeptide (ha2 gp) is a promising new candidate for such an influenza vaccine. helical domain and the fusion peptide (residues 15-1 ... | 2013 | 24004822 |
| prokaryote-expressed m2e protein improves h9n2 influenza vaccine efficacy and protection against lethal influenza a virus in mice. | influenza vaccines are prepared annually based on global epidemiological surveillance data. however, since there is no method by which to predict the influenza strain that will cause the next pandemic, the demand to develop new vaccination strategies with broad cross-reactivity against influenza viruses are clearly important. the ectodomain of the influenza m2 protein (m2e) is an attractive target for developing a vaccine with broad cross-reactivity. for these reasons, we investigated the effica ... | 2013 | 23551908 |
| recombinant m2e protein-based elisa: a novel and inexpensive approach for differentiating avian influenza infected chickens from vaccinated ones. | available avian influenza (aiv) serological diagnostic tests cannot distinguish vaccinated from naturally infected birds. differentiation of vaccinated from infected animals (diva) is currently advocated as a means of achieving the full control of h5n1. in this study, for the first time, recombinant ectodomain of m2 protein (m2e) of avian influenza virus (h5n1 strain) was used for the diva serology test. m2e was cloned into pmal-p4x vector and expressed in e. coli cells. we used western blot to ... | 2013 | 23437243 |
| isolation of novel sequences targeting highly variable viral protein hemagglutinin. | rapid evolution is a hallmark of the viral kingdom and a major concern for developing universal vaccines. the isolation of substantial numbers of viral sequence variants at highly variable viral protein domains remains a major challenge. we previously developed a combinatorial method for the isolation of novel sequences to cope with rapid viral variations at the g-h loop of foot and mouth disease virus vp1 protein [1]. here we present a modification of that method in its application in the rando ... | 2015 | 26150973 |
| an enzyme-linked immunosorbent assay for detection of avian influenza virus subtypes h5 and h7 antibodies. | avian influenza virus (aiv) subtypes h5 and h7 attracts particular attention because of the risk of their potential pathogenicity in poultry. the haemagglutination inhibition (hi) test is widely used as subtype specific test for serological diagnostics despite the laborious nature of this method. however, enzyme-linked immunosorbent assays (elisas) are being explored as an alternative test method.h5 and h7 specific monoclonal antibodies were experimentally raised and used in the development of i ... | 2013 | 24256721 |
| clinical, epidemiological and virological characteristics of the first detected human case of avian influenza a(h5n6) virus. | a human infection with novel avian influenza a h5n6 virus emerged in changsha city, china in february, 2014. this is the first detected human case among all human cases identified from 2014 to early 2016. we obtained and summarized clinical, epidemiological, and virological data from this patient. complete genome of the virus was determined and compared to other avian influenza viruses via the construction of phylogenetic trees using the neighbor-joining approach. a girl aged five and half years ... | 2016 | 26973295 |
| evolutionary dynamics and global diversity of influenza a virus. | the increasing number of zoonotic infections caused by influenza a virus (iav) subtypes of avian origin (e.g., h5n1 and h7n9) in recent years underscores the need to better understand the factors driving iav evolution and diversity. to evaluate the current feasibility of global analyses to contribute to this aim, we evaluated information in the public domain to explore iav evolutionary dynamics, including nucleotide substitution rates and selection pressures, using 14 iav subtypes in 32 differen ... | 2015 | 26311890 |
| enzootic genotype s of h9n2 avian influenza viruses donates internal genes to emerging zoonotic influenza viruses in china. | avian influenza viruses of subtype h9n2 are widely prevalent in poultry in many asian countries, and the segmented nature of the viral genome results in multiple distinct genotypes via reassortment. in this study, genetic evolution of h9n2 viruses circulating in eastern china during 2007-2013 was analyzed. the results showed that the diversity of the gene constellations generated six distinct genotypes, in which a novel genotype (s) bearing the backbone of a/chicken/shanghai/f/98-like viruses by ... | 2014 | 25457363 |
| serologic evidence of avian influenza virus infections among nigerian agricultural workers. | nigeria has had multiple incursions of highly pathogenic avian influenza a (hpai) h5n1 virus into its poultry population since 2006. this study aimed to determine if nigerians exposed to poultry had evidence of avian influenza virus transmission to man. between 2008 and 2010, 316 adult farmers and open market workers and 54 age-group matched, non-animal exposed controls were enrolled in a prospective, population-based study of zoonotic influenza transmission in four towns in southeastern nigeria ... | 2013 | 23400898 |
| receptor specificity and erythrocyte binding preferences of avian influenza viruses isolated from india. | hemagglutination (ha) and hemagglutination inhibition (hi) assays are conventionally used for detection and identification of influenza viruses. hi assay is also used for detection of antibodies against influenza viruses. primarily turkey or chicken erythrocytes [red blood cells (rbcs)] are used in these assays, as they are large, nucleated, and sediment fast, which makes it easy to determine the titer. human influenza viruses agglutinate rbcs from chicken, human, and guinea pig, but not from ho ... | 2012 | 23110802 |
| genome sequence of a novel reassortant h3n2 avian influenza virus from domestic mallard ducks in eastern china. | the h3 subtype avian influenza virus (aiv) can provide genes for human influenza virus through gene reassortment, which raises great concerns in terms of its potential threat to human health. here, we report the complete genome sequence of a novel h3n2 aiv isolated from domestic ducks in the jiangsu province of eastern china in 2004, which is a natural recombinant virus whose genes are derived from h3n8, h5n1, h5n2, h11n2, h4n6, and h1n1 aivs. this genome will help to understand the epidemiology ... | 2013 | 23580713 |
| complete genome sequence of a novel reassortant h11n2 avian influenza virus isolated from a live poultry market in eastern china. | a/chicken/nanjing/908/2009(h11n2) (ck908) was isolated from a live poultry market in nanjing, china. using pcr and sequencing analysis, we obtained the complete genome sequences of the ck908 virus. the sequence analysis demonstrated that this h11n2 virus was a novel reassortant aiv whose pb1, pb2, pa, ha, np, na, m, and ns genes originated from h9n2, h7n7, h5n2, h11n8, h3n6, h6n2, h1n1, and h5n1, respectively. knowledge regarding the complete genome sequences of the ck908 virus will be useful fo ... | 2012 | 23087108 |
| genetically diverse low pathogenicity avian influenza a virus subtypes co-circulate among poultry in bangladesh. | influenza virus surveillance, poultry outbreak investigations and genomic sequencing were assessed to understand the ecology and evolution of low pathogenicity avian influenza (lpai) a viruses in bangladesh from 2007 to 2013. we analyzed 506 avian specimens collected from poultry in live bird markets and backyard flocks to identify influenza a viruses. virus isolation-positive specimens (n = 50) were subtyped and their coding-complete genomes were sequenced. the most frequently identified subtyp ... | 2016 | 27010791 |
| long-term variation in influenza a virus prevalence and subtype diversity in migratory mallards in northern europe. | data on long-term circulation of pathogens in wildlife populations are seldom collected, and hence understanding of spatial-temporal variation in prevalence and genotypes is limited. here, we analysed a long-term surveillance series on influenza a virus (iav) in mallards collected at an important migratory stopover site from 2002 to 2010, and characterized seasonal dynamics in virus prevalence and subtype diversity. prevalence dynamics were influenced by year, but retained a common pattern for a ... | 2014 | 24573857 |
| reassortment of influenza a viruses in wild birds in alaska before h5 clade 2.3.4.4 outbreaks. | sampling of mallards in alaska during september 2014-april 2015 identified low pathogenic avian influenza a virus (subtypes h5n2 and h1n1) that shared ancestry with highly pathogenic reassortant h5n2 and h5n1 viruses. molecular dating indicated reassortment soon after interhemispheric movement of h5n8 clade 2.3.4.4, suggesting genetic exchange in alaska or surrounds before outbreaks. | 2017 | 28322698 |
| human monoclonal antibody 81.39a effectively neutralizes emerging influenza a viruses of group 1 and 2 hemagglutinins. | the pandemic threat posed by emerging zoonotic influenza a viruses necessitates development of antiviral agents effective against various antigenic subtypes. human monoclonal antibody (hmab) targeting the hemagglutinin (ha) stalk offers a promising approach to control influenza virus infections. here, we investigated the ability of the hmab 81.39a to inhibit in vitro replication of human and zoonotic viruses, representing 16 ha subtypes. the majority of viruses were effectively neutralized by 81 ... | 2016 | 27630240 |
| rapid detection of avian influenza virus h5n1 in chicken tracheal samples using an impedance aptasensor with gold nanoparticles for signal amplification. | highly pathogenic avian influenza virus h5n1 is a continuous threat to public health and poultry industry. the recurrence of the h5n1 led us to develop a robust, specific, and rapid detection method for the virus. in this study, an impedance aptasensor was developed for the virus detection using specific h5n1 aptamer and a gold interdigitated microelectrode. streptavidin was immobilized on the microelectrode surface and biotin labeled h5n1 aptamer was bound to the immobilized streptavidin. the m ... | 2016 | 27452670 |
| protective efficacy of an h5n1 inactivated vaccine against challenge with lethal h5n1, h5n2, h5n6, and h5n8 influenza viruses in chickens. | the goose/guangdong-lineage h5 viruses have evolved into diverse clades and subclades based on their hemagglutinin (ha) gene during their circulation in wild birds and poultry. since late 2013, the clade 2.3.4.4 viruses have become widespread in poultry and wild bird populations around the world. different subtypes of the clade 2.3.4.4 h5 viruses, including h5n1, h5n2, h5n6, and h5n8, have caused vast disease outbreaks in poultry in asia, europe, and north america. in this study, we developed a ... | 2016 | 27309064 |
| novel highly pathogenic avian a(h5n2) and a(h5n8) influenza viruses of clade 2.3.4.4 from north america have limited capacity for replication and transmission in mammals. | highly pathogenic influenza a(h5n8) viruses from clade 2.3.4.4 were introduced to north america by migratory birds in the fall of 2014. reassortment of a(h5n8) viruses with avian viruses of north american lineage resulted in the generation of novel a(h5n2) viruses with novel genotypes. through sequencing of recent avian influenza viruses, we identified pb1 and np gene segments very similar to those in the viruses isolated from north american waterfowl prior to the introduction of a(h5n8) to nort ... | 2017 | 27303732 |
| [determination of influenza virus h5n1 and h7n9 using masa technology]. | to set up a new rapid method for the rapid determination of influenza virus h5n1 and h7n9 basing on the multi-analyte suspension array (masa) technology. sequence analysis and design of degenerate primers and specific probes were set in the comparison and analysis of h5, n1, h7 and n9 genes. in combination with masa technology, these primers and probes were used for the determination of samples of h5n1 and h7n9 and other subtypes ( h1n1, ph1n1, h5n2, h3n2 and h9n2). we developed a rapid determin ... | 2015 | 26951004 |
| generation of a reassortant avian influenza virus h5n2 vaccine strain capable of protecting chickens against infection with egyptian h5n1 and h9n2 viruses. | avian influenza h5n1 viruses have been enzootic in egyptian poultry since 2006. avian influenza h9n2 viruses which have been circulating in egyptian poultry since 2011 showed high replication rates in embryonated chicken eggs and mammalian cells. | 2016 | 26620838 |
| genedia multi influenza ag rapid test for detection and h1, h3, and h5 subtyping of influenza viruses. | rapid identification and subtype determination of influenza virus is important in managing infected patients. rapid influenza diagnostic tests (ridts) are widely used in this manner, but most can only detect influenza a and b viruses without subtyping. a new ridt, genedia multi influenza ag rapid test (genedia), was developed for detection of influenza a and b viruses and also subtyping of influenza a to h1, h3, h5 which has not been possible with other ridts. | 2015 | 26540461 |
| pathogenesis and transmission of novel highly pathogenic avian influenza h5n2 and h5n8 viruses in ferrets and mice. | a novel highly pathogenic avian influenza (hpai) h5n8 virus, first detected in january 2014 in poultry and wild birds in south korea, has spread throughout asia and europe and caused outbreaks in canada and the united states by the end of the year. the spread of h5n8 and the novel reassortant viruses, h5n2 and h5n1 (h5nx), in domestic poultry across multiple states in the united states pose a potential public health risk. to evaluate the potential of cross-species infection, we determined the pa ... | 2015 | 26223637 |
| antiviral effects of novel herbal medicine kiom-c, on diverse viruses. | in order to identify new potential antiviral agents, recent studies have advocated thorough testing of herbal medicines or natural substances that are traditionally used to prevent viral infections. antiviral activities and the mechanism of action of the total aqueous extract preparation of kiom-c, a novel herbal medicine, against diverse types of viruses were investigated. in vitro antiviral activity against a/puerto rico/8/34 (h1n1) (pr8), vesicular stomatitis virus (vsv), and newcastle diseas ... | 2015 | 25942440 |
| epimedium koreanum nakai displays broad spectrum of antiviral activity in vitro and in vivo by inducing cellular antiviral state. | epimedium koreanum nakai has been extensively used in traditional korean and chinese medicine to treat a variety of diseases. despite the plant's known immune modulatory potential and chemical make-up, scientific information on its antiviral properties and mode of action have not been completely investigated. in this study, the broad antiviral spectrum and mode of action of an aqueous extract from epimedium koreanum nakai was evaluated in vitro, and moreover, the protective effect against diverg ... | 2015 | 25609307 |
| pandemic preparedness with live attenuated influenza vaccines based on a/leningrad/134/17/57 master donor virus. | continuously evolving avian influenza viruses pose a constant threat to the human public health. in response to this threat, a number of pandemic vaccine candidates have been prepared and evaluated in animal models and clinical trials. this review summarizes the data from the development and preclinical and clinical evaluation of pandemic live attenuated influenza vaccines (laiv) based on russian master donor virus a/leningrad/134/17/57. laiv candidates of h5n1, h5n2, h7n3, h1n1 and h2n2 subtype ... | 2015 | 25555687 |
| antibody response to dna vaccine against h5n1 avian influenza virus in broilers immunized according to three schedules. | broiler type chickens were immunized intramuscularly with a dna vaccine encoding hemagglutinin (ha) from h5n1 avian influenza virus. the chickens were divided into four groups: control group which was not immunized, a group which obtained only one dose, and two groups which were immunized twice, one group with a boost two weeks after the priming and the other four weeks. blood samples were collected at several time points and the dynamics of the humoral response to the vaccine was studied. high ... | 2014 | 25180224 |
| anti-influenza activity of alchemilla mollis extract: possible virucidal activity against influenza virus particles. | influenza virus infection is a major public health problem that leads to significant morbidity and mortality. the emergence of resistance to the currently available anti-influenza agents has necessitated the development of new drugs with novel targets. studying known ethno-medicinal plants is a promising approach for the discovery of new antiviral compounds. alchemilla mollis is used in traditional medicine in europe for different indications, including minimizing the symptoms of a sore throat. ... | 2013 | 24270383 |
| adjuvant efficacy of momv against avian influenza virus infection in mice. | highly pathogenic avian influenza h5n1 viruses are found chiefly in birds and have caused severe disease and death in infected humans. development of influenza vaccines capable of inducing heterosubtypic immunity against a broad range of influenza viruses is the best option for the preparedness, since vaccination remains the principal method in controlling influenza viral infections. here, a momv-adjuvanted recombinant h5n2 (rh5n2) whole virus antigen vaccine with a/environment/korea/w149/06(h5n ... | 2013 | 24173647 |
| [local antibody immune responses in influenza patients and persons vaccinated with seasonal, pre-pandemic, and pandemic live attenuated influenza vaccines]. | mucosal immunity is one of the most important factors of human anti-influenza defense. the data about local immune responses in influenza a (h3n2) patients and in persons vaccinated within 2000-2009 with different seasonal laivs, a (h1n1)pdm2009 laiv, and a (h5n2) laiv are discussed. the influenza infection resulted in the larger quantities of local iga and igg conversions than seasonal laiv vaccination. 56% of young (18-21 y.o.) persons had high titers (> or = 1:64) of iga to a (h1n1)pdm2009 vi ... | 2016 | 24006632 |
| immunogenicity and protective efficacy of cold-adapted x-31 live attenuated pre-pandemic h5n1 influenza vaccines. | despite global efforts to control influenza viruses, they have taken a heavy toll on human public health worldwide. among particular threats is highly pathogenic avian h5n1 influenza virus (hpai) due to not only its high mortality in humans but also possible human-to-human transmission either through reassortment with other human influenza viruses such as 2009 pandemic h1n1 influenza virus, or by genetic mutations. with the aim of developing effective vaccines against the h5n1 viruses, we genera ... | 2013 | 23742997 |
| antiviral activity of stachyflin on influenza a viruses of different hemagglutinin subtypes. | the hemagglutinin (ha) of influenza viruses is a possible target for antiviral drugs because of its key roles in the initiation of infection. although it was found that a natural compound, stachyflin, inhibited the growth of h1 and h2 but not h3 influenza viruses in mdck cells, inhibitory activity of the compound has not been assessed against h4-h16 influenza viruses and the precise mechanism of inhibition has not been clarified. | 2013 | 23587221 |
| an in vitro network of intermolecular interactions between viral rna segments of an avian h5n2 influenza a virus: comparison with a human h3n2 virus. | the genome of influenza a viruses (iav) is split into eight viral rnas (vrnas) that are encapsidated as viral ribonucleoproteins. the existence of a segment-specific packaging mechanism is well established, but the molecular basis of this mechanism remains to be deciphered. selective packaging could be mediated by direct interaction between the vrna packaging regions, but such interactions have never been demonstrated in virions. recently, we showed that the eight vrnas of a human h3n2 iav form ... | 2013 | 23221636 |
| prior infection of chickens with h1n1 avian influenza virus elicits heterologous protection against highly pathogenic h5n2. | current vaccines for influenza are primarily killed whole virus vaccines that elicit antibody responses to the homologous virus but lack protection against heterologous viruses. using chickens as a model we have explored the possibility of using a live low pathogenic avian influenza (lpai) a/goose/ab/223/2005 h1n1 virus as a vaccine to generate protective immunity against heterologous highly pathogenic avian influenza (hpai) a/chicken/pensylvania/1370/1983 h5n2 virus challenge. virus replicated ... | 2012 | 23084852 |
| evaluation of the efficacy of a pre-pandemic h5n1 vaccine (mg1109) in mouse and ferret models. | the threat of a highly pathogenic avian influenza (hpai) h5n1 virus causing the next pandemic remains a major concern. in this study, we evaluated the immunogenicity and efficacy of an inactivated whole-virus h5n1 pre-pandemic vaccine (mg1109) formulated by green cross co., ltd containing the hemagglutinin (ha) and neuraminidase (na) genes of the clade 1 a/vietnam/1194/04 virus in the backbone of a/puerto rico/8/34 (rgvietnam/04xpr8/34). administration of the mg1109 vaccine (2-doses) in mice and ... | 2012 | 22752912 |
| [stimulation of homo- and heterologic t-cell immunological memory in volunteers inoculated with live influenza a (h5n2) reassortant vaccine]. | the study deals with the ability of live attenuated reassortant influenza vaccine (laiv) a (h5n2) to stimulate a cd4+ and cd8+ immunological memory t cell-mediated immune response in volunteers. these data were compared with the quantitative characteristics of a humoral immune response. a two-dose regimen of intranasal vaccination of avian influenza naïve people with a (h5n2) laiv induced the production of circulating cd4+ and cd8+ memory cells specific to both a (h5n2) and seasonal a (h1n1) inf ... | 2016 | 22624472 |
| activation of type i and iii interferon signalling pathways occurs in lung epithelial cells infected with low pathogenic avian influenza viruses. | the host response to the low pathogenic avian influenza (lpai) h5n2, h5n3 and h9n2 viruses were examined in a549, mdck, and cef cells using a systems-based approach. the h5n2 and h5n3 viruses replicated efficiently in a549 and mdck cells, while the h9n2 virus replicated least efficiently in these cell types. however, all lpai viruses exhibited similar and higher replication efficiencies in cef cells. a comparison of the host responses of these viruses and the h1n1/wsn virus and low passage ph1n1 ... | 2012 | 22470468 |
| cold-adapted pandemic 2009 h1n1 influenza virus live vaccine elicits cross-reactive immune responses against seasonal and h5 influenza a viruses. | the rapid transmission of the pandemic 2009 h1n1 influenza virus (ph1n1) among humans has raised the concern of a potential emergence of reassortment between ph1n1 and highly pathogenic influenza strains, especially the avian h5n1 influenza virus. here, we report that the cold-adapted ph1n1 live attenuated vaccine (caph1n1) elicits cross-reactive immunity to seasonal and h5 influenza a viruses in the mouse model. immunization with caph1n1 induced both systemic and mucosal antibodies with broad r ... | 2012 | 22438541 |
| serological investigation of highly pathogenic avian influenza h5n2 in ostriches (struthio camelus). | an ostrich farm of 929 birds that tested polymerase chain reaction-positive for highly pathogenic avian influenza h5n2 in a single sample was designated for culling, despite no evidence of sero-conversion as assessed by haemagglutination inhibition (hi) tests. a month later and immediately prior to culling, all birds were bled and tested with an idexx avian influenza virus (aiv) nucleoprotein (np)-specific enzyme-linked immunosorbent assay (elisa) and a high sero-prevalence was detected. to addr ... | 2013 | 23607480 |
| molecular analysis of the 2011 hpai h5n2 outbreak in ostriches, south africa. | the third outbreak of highly pathogenic avian influenza (hpai) h5n2 in less than seven years affected ostriches of south africa's western cape during 2011. twenty farms tested pcr positive for the presence of hpai h5n2 between march and november 2011. three hpai h5n2 (ai2114, ai2214, ai2512) and 1 h1n2 (ai2887) viruses were isolated during this period, but h6n2 and h1n2 infections of ostriches were also confirmed by pcr. hpai h5n2 isolate ai2114 produced an intravenous pathogenicity index (ivpi) ... | 2012 | 23402106 |
| [testing of apathogenic influenza virus h5n3 as a poultry live vaccine]. | four h5n2 experimental vaccine strains and the apathogenic wild duck h5n3 influenza virus a/duck/ moscow/4182/2010 (dk/4182) were tested as a live poultry vaccine. experimental strains had the hemagglutinin of the a/vietnam/1203/04 strain lacking the polybasic ha cleavage site or the hemagglutinin from attenuated virus (ku/ at) that was derived from the highly pathogenic influenza virus a/chicken/kurgan/3/2005 (h5n1). the hemagglutinin of the ku-at has the amino acid substitutions asp54/asn and ... | 2015 | 26665435 |
| genetic stability of live attenuated vaccines against potentially pandemic influenza viruses. | ensuring genetic stability is a prerequisite for live attenuated influenza vaccine (laiv). this study describes the results of virus shedding and clinical isolates' testing of phase i clinical trials of russian laivs against potentially pandemic influenza viruses in healthy adults. | 2015 | 26432909 |
| [evaluation of the anti-neuraminidase antibodies in clinical trials of the live influenza vaccine of the a(h5n2) subtype]. | in the current study, we evaluated the neuraminidase-inhibition (ni) antibodies among volunteers during the phase i and phase ii of the clinical trials of a monovalent live attenuated influenza vaccine (laiv) a/17/duck/ potsdam/86/92(h5n2). the reassortant influenza virus rn2/57-human a(h7n2) containing neuraminidase (na) from the a/leningrad/134/17/57(h2n2) was used in ni test. it was shown that two doses of the monovalent laiv a(h5n2) led to a statistically significant increase in the ni antib ... | 2016 | 24772644 |
| critical role of segment-specific packaging signals in genetic reassortment of influenza a viruses. | the fragmented nature of the influenza a genome allows the exchange of gene segments when two or more influenza viruses infect the same cell, but little is known about the rules underlying this process. here, we studied genetic reassortment between the a/moscow/10/99 (h3n2, mo) virus originally isolated from human and the avian a/finch/england/2051/91 (h5n2, en) virus and found that this process is strongly biased. importantly, the avian ha segment never entered the mo genetic background alone b ... | 2013 | 24043788 |
| tenacity of low-pathogenic avian influenza viruses in different types of poultry litter. | to determine the risk of infection associated with exposure to low-pathogenic avian influenza (ai) virus-contaminated poultry litter, the tenacity of low pathogenic a/ck/ca/431/00(h6n2), a/mallard/mn/355779/00(h5n2), and a/turkey/ohio/313053/04(h3n2) was evaluated. viral stocks were incubated with poultry litter from commercial flocks at 25°c. three types of poultry litter, wood shavings, shavings plus gypsum, and shavings plus peanut hulls, from commercial broiler flocks were used. the 3 low-pa ... | 2012 | 22802163 |
| serological survey for avian influenza in turkeys in three states of southwest nigeria. | since the first outbreak of avian influenza (ai) in nigeria in 2006, there has been continuous monitoring of the disease in chickens with little attention given to turkeys. as part of on-going surveillance for ai in southwest nigeria, we used a competitive elisa to detect anti-ai virus antibodies in 520 turkey sera obtained from poultry farms in oyo, osun, and ondo states while haemagglutination inhibiting antibodies against low pathogenic ai viruses (lpaivs) were detected using h3n8 and h5n2 su ... | 2015 | 26664747 |
| complete genomic sequence of a novel reassortant h4n2 avian influenza virus isolated from domestic ducks in jiangsu, china. | here, we report the complete genomic sequence of a novel reassortant h4n2 influenza virus isolated from domestic ducks in the jiangsu province of china in 2011. phylogenetic analysis showed that all the viral genes except for hemagglutinin (ha) were highly homologous to the clade 2.3.4 h5n2 viruses. the data suggest that genetic reassortment occurred between h4 and h5n2 avian influenza viruses, which highlights the role of domestic poultry as a reassortment vessel in china. | 2013 | 23516214 |
| emerging highly pathogenic h5 avian influenza viruses in france during winter 2015/16: phylogenetic analyses and markers for zoonotic potential. | several new highly pathogenic (hp) h5 avian influenza virus (aiv) have been detected in poultry farms from south-western france since november 2015, among which an hp h5n1. the zoonotic potential and origin of these aivs immediately became matters of concern. one virus of each subtype h5n1 (150169a), h5n2 (150233) and h5n9 (150236) was characterised. all proved highly pathogenic for poultry as demonstrated molecularly by the presence of a polybasic cleavage site in their ha protein - with a sequ ... | 2017 | 28277218 |
| isolation and genetic characterization of a novel 2.2.1.2a h5n1 virus from a vaccinated meat-turkeys flock in egypt. | vaccination of poultry to control highly pathogenic avian influenza virus (hpaiv) h5n1 is used in several countries. hpaiv h5n1 of clade 2.2.1 which is endemic in egypt has diversified into two genetic clades. clade 2.2.1.1 represents antigenic drift variants in vaccinated commercial poultry while clade 2.2.1.2 variants are detected in humans and backyard poultry. little is known about h5n1 infection in vaccinated turkeys under field conditions. | 2017 | 28274236 |
| vaccine efficacy of inactivated, chimeric hemagglutinin h9/h5n2 avian influenza virus and its suitability for the marker vaccine strategy. | in order to produce a dually effective vaccine against h9 and h5 avian influenza viruses that aligns with the diva (differentiating infected from vaccinated animals) strategy, we generated a chimeric h9/h5n2 recombinant vaccine that expressed the whole ha1 region of a/ck/korea/04163/04 (h9n2) and the ha2 region of recent highly pathogenic avian influenza (hpai) a/md/korea/w452/14 (h5n8) viruses. the chimeric h9/h5n2 virus showed in vitro and in vivo growth properties and virulence that were simi ... | 2017 | 28077631 |
| genesis and dissemination of highly pathogenic h5n6 avian influenza viruses. | clade 2.3.4.4 highly pathogenic avian influenza viruses (h5nx) have spread from asia to other parts of the world. since 2014, human infections with clade 2.3.4.4 highly pathogenic avian influenza h5n6 viruses have been continuously reported in china. to investigate the genesis of the virus, we analyzed 123 h5 or n6 environmental viruses sampled from live-poultry markets or farms from 2012 to 2015 in mainland china. our results indicated that clade 2.3.4.4 h5n2/n6/n8 viruses shared the same hemag ... | 2017 | 28003485 |
| virus-like particles displaying h5, h7, h9 hemagglutinins and n1 neuraminidase elicit protective immunity to heterologous avian influenza viruses in chickens. | avian influenza (ai) viruses circulating in wild birds pose a serious threat to public health. human and veterinary vaccines against ai subtypes are needed. here we prepared triple-subtype vlps that co-localized h5, h7 and h9 antigens derived from h5n1, h7n3 and h9n2 viruses. vlps also contained influenza n1 neuraminidase and retroviral gag protein. the h5/h7/h9/n1/gag vlps were prepared using baculovirus expression. biochemical, functional and antigenic characteristics were determined including ... | 2017 | 27936463 |
| the response of mute swans (cygnus olor, gm. 1789) to vaccination against avian influenza with an inactivated h5n2 vaccine. | recent epidemics of highly pathogenic avian influenza (hpai) produced an unprecedented number of cases in mute swans (cygnus olor) in european countries, which indicates that these birds are very sensitive to the h5n1 virus. the hpai outbreaks stirred a debate on the controversial stamping-out policy in populations of protected bird species. after preventive vaccination had been approved in the european union, several countries have introduced vaccination schemes to protect poultry, captive wild ... | 2016 | 27770803 |
| protective efficacy of a prime-boost protocol using h5-dna plasmid as prime and inactivated h5n2 vaccine as the booster against the egyptian avian influenza challenge virus. | in this study, a recombinant dna plasmid was constructed, encoding for ha1 of a selected egyptian h5n1 virus (isolated during the 2012 outbreaks). in the immunization and challenge experiments, spf chickens received 1 or 2 doses of h5-dna plasmid prime, and boosted with the inactivated h5n2 vaccine. haemagglutination inhibition (hi) titers, protection levels, and the magnitude of virus shedding were compared to that of the chickens that received either dna plasmid or inactivated h5n2 vaccine alo ... | 2017 | 27640441 |
| changes in adaptation of h5n2 highly pathogenic avian influenza h5 clade 2.3.4.4 viruses in chickens and mallards. | h5n2 highly pathogenic avian influenza (hpai) viruses caused a severe poultry outbreak in the united states (u.s.) during 2015. in order to examine changes in adaptation of this viral lineage, the infectivity, pathogenicity and transmission of poultry h5n2 viruses were investigated in chickens and mallards in comparison to the wild duck 2014 u.s. index h5n2 virus. the four poultry isolates examined had a lower mean bird infectious dose than the index virus but still transmitted poorly to direct ... | 2016 | 27632565 |
| pathogenicity and transmission of h5 and h7 highly pathogenic avian influenza viruses in mallards. | wild aquatic birds have been associated with the intercontinental spread of h5 subtype highly pathogenic avian influenza (hpai) viruses of the a/goose/guangdong/1/96 (gs/gd) lineage during 2005, 2010, and 2014, but dispersion by wild waterfowl has not been implicated with spread of other hpai viruses. to better understand why gs/gd h5 hpai viruses infect and transmit more efficiently in waterfowl than other hpai viruses, groups of mallard ducks were challenged with one of 14 different h5 and h7 ... | 2016 | 27558429 |
| epidemiological and evolutionary inference of the transmission network of the 2014 highly pathogenic avian influenza h5n2 outbreak in british columbia, canada. | the first north american outbreak of highly pathogenic avian influenza (hpai) involving a virus of eurasian a/goose/guangdong/1/1996 (h5n1) lineage began in the fraser valley of british columbia, canada in late november 2014. a total of 11 commercial and 1 non-commercial (backyard) operations were infected before the outbreak was terminated. control measures included movement restrictions that were placed on a total of 404 individual premises, 150 of which were located within a 3 km radius of an ... | 2016 | 27489095 |
| the enigma of the apparent disappearance of eurasian highly pathogenic h5 clade 2.3.4.4 influenza a viruses in north american waterfowl. | one of the major unresolved questions in influenza a virus (iav) ecology is exemplified by the apparent disappearance of highly pathogenic (hp) h5n1, h5n2, and h5n8 (h5nx) viruses containing the eurasian hemagglutinin 2.3.4.4 clade from wild bird populations in north america. the introduction of eurasian lineage hp h5 clade 2.3.4.4 h5n8 iav and subsequent reassortment with low-pathogenic h?n2 and h?n1 north american wild bird-origin iavs in late 2014 resulted in widespread hp h5nx iav infections ... | 2016 | 27457948 |
| novel avian influenza a (h5n6) viruses isolated in migratory waterfowl before the first human case reported in china, 2014. | in may 2014, china formally confirmed the first human infection with the novel h5n6 avian influenza virus (aiv) in sichuan province. before the first human case was reported, surveillance of aivs in wild birds resulted in the detection of three h5n6 viruses in faecal samples from migratory waterfowl in chenhu wetlands, hubei province, china. genetic and phylogenetic analyses revealed that these three novel viruses were closely related to the h5n6 virus that has caused human infections in china s ... | 2016 | 27431568 |
| highly sensitive sandwich-type spr based detection of whole h5nx viruses using a pair of aptamers. | in this research, we report highly sensitive and specific sandwich-type spr-based biosensor for the detection h5nx whole viruses. a few of aptamers, for the first time, were successfully screened and characterized for whole avian influenza (ai) viruses, h5nx, by using multi-go-selex method. the affinities of the aptamers developed in this study were ranged from 8×10(4) to 1×10(4)eid50/ml, and the aptamers if22, if23 were found to be specific to h5n1 and h5n8, respectively. in addition, some flex ... | 2016 | 27387259 |
| widespread detection of highly pathogenic h5 influenza viruses in wild birds from the pacific flyway of the united states. | a novel highly pathogenic avian influenza virus belonging to the h5 clade 2.3.4.4 variant viruses was detected in north america in late 2014. motivated by the identification of these viruses in domestic poultry in canada, an intensive study was initiated to conduct highly pathogenic avian influenza surveillance in wild birds in the pacific flyway of the united states. a total of 4,729 hunter-harvested wild birds were sampled and highly pathogenic avian influenza virus was detected in 1.3% (n = 6 ... | 2016 | 27381241 |
| highly pathogenic avian influenza viruses and generation of novel reassortants, united states, 2014-2015. | asian highly pathogenic avian influenza a(h5n8) viruses spread into north america in 2014 during autumn bird migration. complete genome sequencing and phylogenetic analysis of 32 h5 viruses identified novel h5n1, h5n2, and h5n8 viruses that emerged in late 2014 through reassortment with north american low-pathogenicity avian influenza viruses. | 2016 | 27314845 |
| benefits and limits of egg yolk vs. serum samples for avian influenza virus serosurveillance. | serologic tests are a valuable tool for retrospective surveillance of avian influenza viruses (aiv) and monitoring of postvaccination host immune response. yet collection of serum samples, particularly in adult breeder chickens, is laborious, intrusive to birds, and may pose a serious risk to the biosecurity of a flock. in this study we compared the level of aiv-specific antibody titers in eggs and serum samples obtained from broiler breeder chickens vaccinated at 6, 12, and 18 wk of age with h5 ... | 2016 | 27309294 |
| case series of turkey farms from the h5n2 highly pathogenic avian influenza outbreak in the united states during 2015. | between december 2014 and june 2015, an outbreak of h5n2 hpai caused the largest and most expensive agriculture emergency in u.s. department of agriculture-animal and plant health inspection service history. the outbreak affected 21 states; 232 poultry farms (211 commercial and 21 backyard) were affected, and approximately 49.6 million birds were depopulated on poultry farms. the majority of affected farms were commercial turkey operations (n = 160). this report is a case series describing 104 h ... | 2016 | 27309289 |
| high rates of detection of clade 2.3.4.4 highly pathogenic avian influenza h5 viruses in wild birds in the pacific northwest during the winter of 2014-15. | in 2014, clade 2.3.4.4 h5n8 highly pathogenic avian influenza (hpai) viruses spread across the republic of korea and ultimately were reported in china, japan, russia, and europe. mortality associated with a reassortant hpai h5n2 virus was detected in poultry farms in western canada at the end of november. the same strain (with identical genetic structure) was then detected in free-living wild birds that had died prior to december 8, 2014, of unrelated causes in whatcom county, washington, u. s. ... | 2016 | 27309079 |
| is the optimal ph for membrane fusion in host cells by avian influenza viruses related to host range and pathogenicity? | influenza viruses isolated from wild ducks do not replicate in chickens. this fact is not explained solely by the receptor specificity of the hemagglutinin (ha) from such viruses for target host cells. to investigate this restriction in host range, the fusion activities of ha molecules from duck and chicken influenza viruses were examined. influenza viruses a/duck/mongolia/54/2001 (h5n2) (dk/mng) and a/chicken/ibaraki/1/2005 (h5n2) (ck/ibr), which replicate only in their primary hosts, were used ... | 2016 | 27231009 |
| novel highly pathogenic avian h5 influenza a viruses in live poultry markets, wuxi city, china, 2013-2014. | during 12 recent months of periodic influenza virus surveillance at 9 live poultry markets in wuxi city china, we identified multiple highly pathogenic h5n6, h5n8, h5n2, and h5n1 avian influenza viruses. the variety of potentially pandemic viruses in this low-risk area is disconcerting and portends an increased pandemic threat. | 2016 | 27186580 |
| fatal influenza a (h5n1) virus infection in zoo-housed tigers in yunnan province, china. | from 2014 to 2015, three cases of highly pathogenic avian influenza infection occurred in zoo-housed north-east china tigers (panthera tigris ssp.altaica) and four tigers died of respiratory distress in succession in yunnan province, china. we isolated and characterized three highly pathogenic avian influenza a(h5n1) viruses from these tigers. phylogenetic analysis indicated that a/tiger /yunnan /tig1404 /2014(h5n1) belongs to the provisional subclade 2.3.4.4e which were novel reassortant influe ... | 2016 | 27162026 |
| highly pathogenic avian influenza h5n6 viruses exhibit enhanced affinity for human type sialic acid receptor and in-contact transmission in model ferrets. | since may 2014, highly pathogenic avian influenza h5n6 virus has been reported to cause six severe human infections three of which were fatal. the biological properties of this subtype, in particular its relative pathogenicity and transmissibility in mammals, are not known. we characterized the virus receptor-binding affinity, pathogenicity, and transmissibility in mice and ferrets of four h5n6 isolates derived from waterfowl in china from 2013-2014. all four h5n6 viruses have acquired a binding ... | 2016 | 27122581 |
| lack of chicken adaptation of newly emergent eurasian h5n8 and reassortant h5n2 high pathogenicity avian influenza viruses in the u.s. is consistent with restricted poultry outbreaks in the pacific flyway during 2014-2015. | in 2014-2015, the u.s. experienced an unprecedented outbreak of eurasian clade 2.3.4.4 h5 highly pathogenic avian influenza (hpai) virus, initially affecting mainly wild birds and few backyard and commercial poultry premises. to better model the outbreak, the pathogenesis and transmission dynamics of representative eurasian h5n8 and reassortant h5n2 clade 2.3.4.4 hpai viruses detected early in the north american outbreak were investigated in chickens. high mean chicken infectious doses and lack ... | 2016 | 27110710 |
| molecular characterizations of surface proteins hemagglutinin and neuraminidase from recent h5nx avian influenza viruses. | during 2014, a subclade 2.3.4.4 highly pathogenic avian influenza (hpai) a(h5n8) virus caused poultry outbreaks around the world. in late 2014/early 2015, the virus was detected in wild birds in canada and the united states, and these viruses also gave rise to reassortant progeny, composed of viral rna segments (vrnas) from both eurasian and north american lineages. in particular, viruses were found with n1, n2, and n8 neuraminidase vrnas, and these are collectively referred to as h5nx viruses. ... | 2016 | 27053557 |
| a cationic liposome-dna complexes adjuvant (jvrs-100) enhances the immunogenicity and cross-protective efficacy of pre-pandemic influenza a (h5n1) vaccine in ferrets. | influenza a (h5n1) viruses continue to pose a public health threat. as inactivated h5n1 vaccines are poorly immunogenic, adjuvants are needed to improve the immunogenicity of h5n1 vaccine in humans. here, we investigated the immunogenicity and cross-protective efficacy in ferrets of a clade 2.2-derived vaccine with addition of jvrs-100, an adjuvant consisting of cationic liposome-dna complexes (cldc). after the first vaccination, significantly higher levels of hemagglutination-inhibition (hai) a ... | 2016 | 26967975 |
| evidence for common ancestry among viruses isolated from wild birds in beringia and highly pathogenic intercontinental reassortant h5n1 and h5n2 influenza a viruses. | highly pathogenic clade 2.3.4.4 h5n8, h5n2, and h5n1 influenza a viruses were first detected in wild, captive, and domestic birds in north america in november-december 2014. in this study, we used wild waterbird samples collected in alaska prior to the initial detection of clade 2.3.4.4 h5 influenza a viruses in north america to assess the evidence for: (1) dispersal of highly pathogenic influenza a viruses from east asia to north america by migratory birds via alaska and (2) ancestral origins o ... | 2016 | 26944444 |
| characterization of clade 2.3.4.4 highly pathogenic h5 avian influenza viruses in ducks and chickens. | worldwide dissemination of reassortant variants of h5 clade 2.3.4.4 highly pathogenic avian influenza (hpai) viruses has posed a great threat to the poultry industry. here, we systematically characterized the h5n2, h5n6 and h5n8 influenza viruses in poultry and compared them with those of previous clade 2.3.4 h5n1 virus. all the three h5 subtype reassortants caused systematic infection in ducks, and exhibited efficient direct transmission in ducks. all of them were highly pathogenic in chickens; ... | 2016 | 26711037 |
| assessment of immune responses to h5n1 inactivated influenza vaccine among individuals previously primed with h5n2 live attenuated influenza vaccine. | during the past decade, a number of h5 subtype influenza vaccines have been developed and tested in clinical trials, but most of them induced poor serum antibody responses prompting the evaluation of novel vaccination approaches. one of the most promising ones is a "prime-boost" strategy, which could result in the induction of prompt and robust immune responses to a booster influenza vaccine following priming with homologous or heterologous vaccine strains. in our study we evaluated immunogenici ... | 2015 | 26697973 |
| identification and characterization of a highly pathogenic h5n1 avian influenza a virus during an outbreak in vaccinated chickens in egypt. | highly pathogenic avian influenza a (hpai) h5n1 viruses continue to be a major veterinary and public health problem in egypt. continued surveillance of these viruses is necessary to devise strategies to control the spread of the virus and to monitor its evolutionary patterns. this is a report of the identification of a variant strain of hpai h5n1 virus during an outbreak in 2010 in vaccinated chicken flocks in a poultry farm in assiut, egypt. vaccination of chickens with an oil-emulsified inacti ... | 2015 | 26363196 |
| adaptive mutations in pb2 gene contribute to the high virulence of a natural reassortant h5n2 avian influenza virus in mice. | the highly pathogenic a/chicken/hebei/1102/2010 (hb10) h5n2 virus is a natural reassortant derived from circulating h5n1 and endemic h9n2 avian influenza viruses (aiv). to evaluate the potential of its interspecies transmission, we previously serially passaged the non-virulent hb10 virus in the mouse lung and obtained a high virulence variant (hb10-ma). genomic sequencing revealed five mutations (ha-s227n, pb2-q591k, pb2-d701n, pa-i554v and np-r351k) that distinguished hb10-ma virus from its par ... | 2015 | 26315686 |
| a comparative analysis of host responses to avian influenza infection in ducks and chickens highlights a role for the interferon-induced transmembrane proteins in viral resistance. | chickens are susceptible to infection with a limited number of influenza a viruses and are a potential source of a human influenza pandemic. in particular, h5 and h7 haemagglutinin subtypes can evolve from low to highly pathogenic strains in gallinaceous poultry. ducks on the other hand are a natural reservoir for these viruses and are able to withstand most avian influenza strains. | 2015 | 26238195 |
| serial passage in ducks of a low-pathogenic avian influenza virus isolated from a chicken reveals a high mutation rate in the hemagglutinin that is likely due to selection in the host. | a comparative study of the ability of three low-pathogenic avian influenza virus (lpaiv) isolates to be transmitted from duck to duck was performed. pekin ducks were inoculated with two lpaiv isolates from chickens (a/ck/pa/13609/93 [h5n2], h5n2-ck; a/ck/tx/167280-4/02 [h5n3], h5n3-ck) and one isolate from a wild bird (a/mute swan/ mi/451072/06 [h5n1], h5n1-wb). during the establishment of the passage model, only two viruses (h5n1, h5n2) were able to be transmitted from duck to duck. transmissio ... | 2015 | 26179620 |
| nomenclature updates resulting from the evolution of avian influenza a(h5) virus clades 2.1.3.2a, 2.2.1, and 2.3.4 during 2013-2014. | the a/goose/guangdong/1/96-like hemagglutinin (ha) genes of highly pathogenic avian influenza (hpai) a(h5) viruses have continued to rapidly evolve since the most recent update to the h5 clade nomenclature by the who/oie/fao h5n1 evolution working group. new clades diverging beyond established boundaries need to be identified and designated accordingly. | 2015 | 25966311 |
| development of a dual-protective live attenuated vaccine against h5n1 and h9n2 avian influenza viruses by modifying the ns1 gene. | an increasing number of outbreaks of avian influenza h5n1 and h9n2 viruses in poultry have caused serious economic losses and raised concerns for human health due to the risk of zoonotic transmission. however, licensed h5n1 and h9n2 vaccines for animals and humans have not been developed. thus, to develop a dual h5n1 and h9n2 live-attenuated influenza vaccine (laiv), the ha and na genes from a virulent mouse-adapted avian h5n2 (a/wb/korea/ma81/06) virus and a recently isolated chicken h9n2 (a/ck ... | 2015 | 25959557 |
| emergence of novel clade 2.3.4 influenza a (h5n1) virus subgroups in yunnan province, china. | from december 2013 to march 2014, a major wave of highly pathogenic avian influenza outbreak occurred in poultry in yunnan province, china. we isolated and characterized eight highly pathogenic avian influenza a (h5n1) viruses from poultry. full genome influenza sequences and analyses have been performed. sequence analyses revealed that they belonged to clade 2.3.4 but did not fit within the three defined subclades. the isolated viruses were provisional subclade 2.3.4.4e. the provisional subclad ... | 2015 | 25917492 |
| genetic evolution of h5 highly pathogenic avian influenza virus in domestic poultry in vietnam between 2011 and 2013. | in spite of highly pathogenic avian influenza h5n1 vaccination campaigns for domestic poultry, h5n1 viruses continue to circulate in vietnam. to estimate the prevalence of avian influenza virus in vietnam, surveillance was conducted between november 2011 and february 2013. genetic analysis of 312 highly pathogenic avian influenza h5 viruses isolated from poultry in vietnam was conducted and possible genetic relationships with strains from neighboring countries were investigated. as previously re ... | 2015 | 25743422 |
| genomic and phylogenetic characterization of novel, recombinant h5n2 avian influenza virus strains isolated from vaccinated chickens with clinical symptoms in china. | infection of poultry with diverse lineages of h5n2 avian influenza viruses has been documented for over three decades in different parts of the world, with limited outbreaks caused by this highly pathogenic avian influenza virus. in the present study, three avian h5n2 influenza viruses, a/chicken/shijiazhuang/1209/2013, a/chicken/chiping/0321/2014, and a/chicken/laiwu/0313/2014, were isolated from chickens with clinical symptoms of avian influenza. complete genomic and phylogenetic analyses demo ... | 2015 | 25723387 |