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an sybr green-based real-time rt-pcr assay for the detection of h5 hemagglutinin subtype avian influenza virus.increasing diversity among h5 hemagglutinin (ha) subtype avian influenza (ai) viruses has resulted in the need of novel sensitive and specific molecular assays. in this study, an sybr green-based real-time reverse transcription-pcr (rrt-pcr) assay was developed for the detection of h5 subtype ai virus. sequence analysis of the mexican lineage h5n2 isolates (subgroup b) revealed several mismatches in the primer/hydrolysis probe set reported in the commonly used rrt-pcr assay for the detection of ...201222421464
assessment of national strategies for control of high-pathogenicity avian influenza and low-pathogenicity notifiable avian influenza in poultry, with emphasis on vaccines and vaccination.twenty-nine distinct epizootics of high-pathogenicity avian influenza (hpai) have occurred since 1959. the h5n1 hpai panzootic affecting asia, africa and eastern europe has been the largest among these, affecting poultry and/or wild birds in 63 countries. a stamping-out programme achieved eradication in 24 of these epizootics (and is close to achieving eradication in the current h5n2 epizootic in south african ostriches), but vaccination was added to the control programmes in four epizootics whe ...201122435196
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 ...201222438541
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 ...201222446640
role of nonmigratory mottled ducks (anas fulvigula) as sentinels for avian influenza surveillance.the objective of this study was to evaluate the mottled duck (anas fulvigula), a nonmigratory dabbling duck, as a sentinel species for avian influenza virus (aiv) surveillance. a total of 235 cloacal swabs from 147 live-captured and 88 hunter-harvested mottled ducks during summer (june-august 2007) and winter (november 2007 to january 2008), respectively, were collected along the upper texas coast. samples were screened for aiv using real-time reverse transcription polymerase chain reaction (rrt ...201222448526
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 ...201222470468
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 ...201222534314
phylogeographic analysis of avian influenza viruses isolated from charadriiformes in belgium confirms intercontinental reassortment in gulls.nine influenza viruses isolated from gulls and shorebirds in belgium (2008-2010), including h3n8, h5n2, h6n1, h11n9, h13n6, h13n8, and h16n3 subtypes, were targeted using random amplification and next-generation sequencing. the gene segments of these viruses segregated into three phylogeographic lineage types: (1) segments circulating in waterfowl in eurasia with sporadic introduction in other species and in the americas ("eurasian avian"), (2) segments circulating in american waterfowl with spo ...201222580556
low-pathogenic avian influenza virus a/turkey/ontario/6213/1966 (h5n1) is the progenitor of highly pathogenic a/turkey/ontario/7732/1966 (h5n9).the first confirmed outbreak of highly pathogenic avian influenza (hpai) virus infections in north america was caused by a/turkey/ontario/7732/1966 (h5n9); however, the phylogeny of this virus is largely unknown. this study performed genomic sequence analysis of 11 avian influenza isolates from 1956 to 1979 for comparison with a/turkey/ontario/7732/1966 (h5n9). phylogenetic and genetic analyses included these viruses in combination with all known full-genome sequences of avian viruses isolated b ...201222592261
antigen-capture enzyme-linked immunosorbent assays for detection of different h5 avian influenza a virus.avian influenza a virus (aiv) subtype h5 is divided into american and eurasian lineages, according to hemagglutinin gene sequences. although methods for detecting h5 aivs have been described, no h5 strain-specific detection method has been reported. the purpose of the present study was to develop an antigen-capture enzyme-linked immunosorbent assay (ace) to detect and differentiate between the american and the eurasian h5 aivs. monoclonal antibodies (mabs) against the ha fragment of a eurasian h ...201222621946
[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 ...201622624472
a national study of individuals who handle migratory birds for evidence of avian and swine-origin influenza virus infections.persons with occupational or recreational exposure to migratory birds may be at risk for infection with highly pathogenic avian influenza and other avian influenza viruses since wild birds are the natural reservoir of influenza a. additionally, bird handlers may host avian and swine-origin influenza (ph1n1) virus co-infections, which generate reassortant viruses with high pathogenicity in mammals.201222632900
induction of a protective heterosubtypic immune response against the influenza virus by using recombinant adenoviral vectors expressing hemagglutinin of the influenza h5 virus.influenza viruses are characterized by a high degree of antigenic variability, which causes the annual emergence of flu epidemics and irregularly timed pandemics caused by viruses with new antigenic and biological traits. novel approaches to vaccination can help circumvent this problem. one of these new methods incorporates genetic vaccines based on adenoviral vectors. recombinant adenoviral vectors which contain hemagglutinin-encoding genes from avian h5n1 and h5n2 (ad-ha5-1 and ad-ha5-2) influ ...201022649637
reduction of high pathogenicity avian influenza virus in eggs from chickens once or twice vaccinated with an oil-emulsified inactivated h5 avian influenza vaccine.the negative impact of high pathogenicity avian influenza virus (hpaiv) infection on egg production and deposition of virus in eggs, as well as any protective effect of vaccination, is unknown. individually housed non-vaccinated, sham-vaccinated and inactivated h5n9 vaccinated once or twice adult white leghorn hens were challenged intranasally/intratracheally 3-weeks post-vaccination with h5n2 hpaiv. the non-/sham-vaccinated layers experienced 100% mortality (0% survivability) within 3-4 days po ...201222652397
nanowire transistor-based ultrasensitive virus detection with reversible surface functionalization.we have applied a reusable silicon nanowire field-effect transistor (sinw-fet) as a biosensor to conduct ultrasensitive detection of h5n2 avian influenza virus (aiv) in very dilute solution. the reversible surface functionalization of sinw-fet was made possible using a disulfide linker. in the surface functionalization, 3-mercaptopropyltrimethoxysilane (mptms) was first modified on the sinw-fet (referred to as mptms/sinw-fet), with subsequent dithiothreitol washing to reduce any possible disulfi ...201222715151
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 ...201222752912
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 ...201222802163
complete genome sequence of an h5n2 avian influenza virus isolated from a parrot in southern china.we report the complete genome sequence of an h5n2 avian influenza virus (aiv) that was first isolated from a parrot in guangdong in southern china in 2004. genomic sequence and phylogenetic analyses showed that it was highly homologous with the north american h5n2 viruses and all eight genes of this virus belonged to the north american gene lineage. these data will help in the investigation of the epidemiology and host range of aivs in southern china.201222843854
the threat of highly pathogenic avian influenza h5: will h5n2 infections occur in humans? 201222901729
dog to dog transmission of a novel influenza virus (h5n2) isolated from a canine.in 2009, an influenza virus (iv), a/canine/shandong/jt01/2009 (ca/sd/jt01/09), was isolated from the dog exhibiting respiratory signs in china, and was a novel h5n2. intraspecies transmission of the virus in dog population had thus far remained unclear. to determine whether the novel h5n2 was transmitted among dogs, we conducted contact exposure and inoculation experiments. susceptible dogs were housed in the room which the novel h5n2 infected dogs were housed in. as a result, the direct contact ...201322906528
migration strategy affects avian influenza dynamics in mallards (anas platyrhynchos).studies of pathogen transmission typically overlook that wildlife hosts can include both migrant and resident populations when attempting to model circulation. through the application of stable isotopes in flight feathers, we estimated the migration strategy of mallards (anas platyrhynchos) occurring on california wintering grounds. our study demonstrates that mallards- a principal host of avian influenza virus (aiv) in nature, contribute differently to virus gene flow depending on migration str ...201222971007
novel reassortant highly pathogenic h5n2 avian influenza viruses in poultry in china.there has been multiple evidence that domestic poultry may act as a vessel for the generation of novel influenza a viruses. in this study, we have analyzed the evolution and pathogenicity of 4 h5n2 avian influenza viruses isolated from apparently healthy poultry from h5n1 virus endemic areas in china. phylogenetic analysis revealed that two of these viruses, a/duck/eastern china/1111/2011 (dk/ec/1111/11) and a/goose/eastern china/1112/2011 (gs/ec/1112/11) were derived from reassortment events in ...201223049973
evaluation of a subunit h5 vaccine and an inactivated h5n2 avian influenza marker vaccine in ducks challenged with vietnamese h5n1 highly pathogenic avian influenza virus.the protective efficacy of a subunit avian influenza virus h5 vaccine based on recombinant baculovirus expressed h5 haemagglutinin antigen and an inactivated h5n2 avian influenza vaccine combined with a marker antigen (tetanus toxoid) was compared with commercially available inactivated h5n2 avian influenza vaccine in young ducks. antibody responses, morbidity, mortality, and virus shedding were evaluated after challenge with a vietnamese clade 1 h5n1 hpai virus [a/vn/1203/04 (h5n1)] that was kn ...201023074648
a novel vaccine using nanoparticle platform to present immunogenic m2e against avian influenza infection.using peptide nanoparticle technology, we have designed two novel vaccine constructs representing m2e in monomeric (mono-m2e) and tetrameric (tetra-m2e) forms. groups of specific pathogen free (spf) chickens were immunized intramuscularly with mono-m2e or tetra-m2e with and without an adjuvant. two weeks after the second boost, chickens were challenged with 107.2 eid50 of h5n2 low pathogenicity avian influenza (lpai) virus. m2e-specific antibody responses to each of the vaccine constructs were t ...201123074652
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 ...201223084852
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 ...201223087108
genome sequence of a natural reassortant h5n2 avian influenza virus from domestic mallard ducks in eastern china.here, we report the genomic sequence of a chinese reassortant h5n2 avian influenza virus which possessed the polybasic motif plrekrrk-r/gl at the hemagglutinin cleavage site. phylogenetic analysis showed that all eight genes were of the eurasian lineage, five of which were highly homologous to the endemic clade 2.3.4 h5n1 viruses and their h5n5 reassortant descendants. these data suggested that novel multisubtypic na reassortants bearing the h5n1 backbone could be generated through genetic reass ...201223087121
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 ...201223110802
identification of a novel splice variant form of the influenza a virus m2 ion channel with an antigenically distinct ectodomain.segment 7 of influenza a virus produces up to four mrnas. unspliced transcripts encode m1, spliced mrna2 encodes the m2 ion channel, while protein products from spliced mrnas 3 and 4 have not previously been identified. the m2 protein plays important roles in virus entry and assembly, and is a target for antiviral drugs and vaccination. surprisingly, m2 is not essential for virus replication in a laboratory setting, although its loss attenuates the virus. to better understand how iav might repli ...201223133386
characterization of low-pathogenicity h5 and h7 korean avian influenza viruses in chickens.to date, all isolated highly pathogenic avian influenza (hpai) viruses that cause systemic infection with a high mortality rate in poultry species have been known to belong to either the h5 or h7 subtypes. the hpai viruses may originate because of the insertion of multiple basic amino acids at the cleavage site of the hemagglutinin protein after the low-pathogenic h5 and h7 viruses have been introduced into poultry. in the present study, we investigated the phylogenetic characteristics of the h5 ...201223155017
genetic characterization of a novel recombinant h5n2 avian influenza virus isolated from chickens in tibet.in this report, a novel h5n2 avian influenza virus (aiv) was isolated from chickens in tibet in 2010, western china. phylogenetic analysis demonstrated that it was a natural reassortant between h9n2 and h5n1 subtypes. it is of note that this virus has an hp genotype with ha, pb2, m, and ns genes homologous to those of a/peregrine falcon/hong kong/2142/2008(h5n1)-like hpaiv isolated from dead wild birds. publishing this genome information will contribute to the investigation of avian influenza ep ...201223166246
chicken dendritic cells are susceptible to highly pathogenic avian influenza viruses which induce strong cytokine responses.infection with highly pathogenic avian influenza (hpai) in birds and mammals is associated with severe pathology and increased mortality. we hypothesize that in contrast to low pathogenicity avian influenza (lpai) infection, hpai infection of chicken dendritic cells (dc) induces a cytokine deregulation which may contribute to their highly pathogenic nature. infection of dc with lpai h7n1 and h5n2 resulted in viral rna and np expression without increase in time, in contrast to hpai h7n1 and h5n2 ...201323178410
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 ...201323221636
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 ...201223264106
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 ...201223274623
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 ...201223320157
systemic distribution of different low pathogenic avian influenza (lpai) viruses in chicken.since we were able to isolate viable virus from brain and lung of h7n1 low pathogenic avian influenza virus (lpaiv) infected chickens, we here examined the distribution of different lpaiv strains in chickens by measuring the viral ai rna load in multiple organs. subtypes of h5 (h5n1, h5n2), h7 (h7n1, h7n7) and h9 (h9n2), of chicken (h5n2, h7n1, h7n7, h9n2), or mallard (h5n1) origin were tested. the actual presence of viable virus was evaluated with virus isolation in organs of h7n7 inoculated ch ...201323324567
chasing notifiable avian influenza in domestic poultry: a case report of low-pathogenic avian influenza h5 viruses in two belgian holdings.in december 2008, bird species in two geographically distant holdings were found positive for h5 viruses following the annual avian influenza serological screening in belgium. the virological tests performed identified in one holding a low-pathogenic avian influenza (lpai) virus subtype h5n2, and a h5 lpai virus was identified by real-time pcr and direct sequencing at the second holding. the first farm was an outdoor mixed holding housing ornamental birds and poultry (n = 6000) and the second a ...201423347839
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 ...201323365205
early regulation of viral infection reduces inflammation and rescues mx-positive mice from lethal avian influenza infection.differing sensitivity of influenza a viruses to antiviral effects of the myxovirus resistance (mx) protein implies varying global gene expression profiles in the host. the role of mx protein during lethal avian influenza (ai) virus infection was examined using mx1-deficient c57bl/6 (b6-mx1(-/-)) and congenic mx1-expressing (b6-mx1(+/+)) mice infected with a virulent, mouse-adapted avian h5n2 ab/korea/ma81/07 (av/ma81) virus. after infection, b6-mx1(+/+) mice were completely protected from lethal ...201323395090
the impact of viral tropism and housing conditions on the transmission of three h5/h7 low pathogenic avian influenza viruses in chickens.in this study, shedding and transmission of three h5/h7 low pathogenic avian influenza viruses (lpaivs) in poultry was characterized and the impact of floor system on transmission was assessed. transmission experiments were simultaneously conducted with two groups of animals housed on either a grid or a floor covered with litter. transmission was observed for h5n2 a/ch/belgium/150vb/99 lpaiv. this virus was shed almost exclusively via the oropharynx and no impact of floor system was seen. transm ...201323398968
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 ...201323400898
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 ...201223402102
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) ...201223402106
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 ...201223402112
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 ...201223402120
the pathogenesis of low pathogenic avian influenza in mallards.mallards are important natural hosts involved in the epidemiology of low pathogenic avian influenza viruses (lpaivs). lpaivs are mainly transmitted by a fecal-oral route and are excreted in high concentrations in the feces. we investigated the pathology, viral antigen distribution, and the expression of alpha2,3 sialic acid (sa) influenza virus receptors in mallards after intranasal inoculation with a/mallard/mn/199106/99 (h3n8) or a/mallard/mn/355779/00 (h5n2). gross lesions were not observed. ...201223402122
effect of different routes of inoculation on infectivity and viral shedding of lpai viruses in mallards.we studied the effect of different routes of inoculation on the infectivity and duration of viral shedding in mallards (anas platyrhynchos) infected with wild bird-origin low pathogenic avian influenza viruses (lpaivs). one-month-old mallards were inoculated with 10(6) median embryo infectious doses of either a/mallard/mn/199106/99 (h3n8) or a/mallard/mn/355779/00 (h5n2) via 1 of 5 different routes: intranasal (in), intratracheal (it), intraocular (io), intracloacal (ic), or intra-ingluvial (ii) ...201223402123
avian influenza virus wild bird surveillance in the azov and black sea regions of ukraine (2010-2011).the azov and black sea basins are part of the transcontinental wild bird migration routes from northern asia and europe to the mediterranean, africa, and southwest asia. these regions constitute an area of transit, stops during migration, and nesting for many different bird species. from september 2010 to september 2011, a wild bird surveillance study was conducted in these regions to identify avian influenza viruses. biological samples consisting of cloacal and tracheal swabs and fecal samples ...201223402128
serosurvey against h5 and h7 avian influenza viruses in italian poultry workers.highly pathogenic (hp) and low pathogenic (lp) avian influenza viruses (aivs) belonging to h5 and h7 subtypes have been found to be associated with human infection as the result of direct transmission from infected poultry. human infections by aivs can cause mild or subclinical disease, and serosurveys are believed to represent an important tool to identify risk of zoonotic transmission. therefore, we sought to examine italian poultry workers exposed during lpai and hpai outbreaks with the aim o ...201223402138
proteins of duck influenza virus responsible for acquisition of pathogenicity in chickens.influenza virus rgvac1sub-p0 (h5n1) (rgvac1-p0), in which a pair of dibasic amino acid residues was introduced at the cleavage site of the ha of a reassortant of h5n2 and h7n1 viruses of duck origin, was low pathogenic in chickens. vac1sub-p3 (h5n1) (vac1-p3) was selected as a highly pathogenic avian influenza virus by 3 consecutive passages in chickens from low pathogenic strain rgvac1-p0. comparison of amino acid sequences of the virus proteins and experimental infection of chickens with a ser ...201323434880
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 ...201323437243
effect of oseltamivir carboxylate consumption on emergence of drug-resistant h5n2 avian influenza virus in mallard ducks.oseltamivir carboxylate (oc) has been detected in environmental waters at various levels during recent influenza seasons in humans, reflecting levels of usage and stability of this drug. in consideration of the role of waterfowl as hosts for influenza viruses that may contribute to human infections, we evaluated the effect of consumption of low doses of oc on development of oseltamivir-resistant influenza virus mutants in mallard ducks (anas platyrhynchos) infected with two different low-pathoge ...201323459475
[the application of radial hemolysis technique in detection of antibodies to avian influenza virus a (h5n1) and pandemic virus a (h1n1) pdm09].the article discusses the results of study that demonstrated the possibility of successful application of radial hemolysis reaction in analyzing the human inoculation immunity to new strains of influenza virus serotype a - a (h5n1) and a (h5n2). the radial hemolysis reaction provides accurate results on introduction of erythrocytes of horse or sheep into hemolytic system instead of erythrocytes of hens applied previously. the technique combines high sensitivity (in comparison with reactions of h ...201223479970
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.201323516214
selection and characterization of dna aptamers for use in detection of avian influenza virus h5n1.aptamers are artificial oligonucleotides (dna or rna) that can bind to a broad range of targets. in diagnostic and detection assays, aptamers represent an alternative to antibodies as recognition agents. the objective of this study was to select and characterize dna aptamers that can specifically bind to avian influenza virus (aiv) h5n1 based on systematic evolution of ligands by exponential enrichment (selex) and surface plasmon resonance (spr). the selection was started with an ssdna (single-s ...201323523887
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 ...201323551908
evaluation of the u.s. department of agriculture's egg pasteurization processes on the inactivation of high-pathogenicity avian influenza virus and velogenic newcastle disease virus in processed egg products.globally, 230,662 metric tons of liquid egg products are marketed each year. the presence of highly pathogenic avian influenza (hpai) or newcastle disease in an exporting country can legitimately inhibit trade in eggs and processed egg products; development and validation of pasteurization parameters are essential for safe trade to continue. the hpai virus (hpaiv) a/chicken/pennsylvania/1370/1983 (h5n2) and velogenic newcastle disease virus (vndv) ampv-1/chicken/california/s01212676/2002 were in ...201323575126
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 ...201323580713
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.201323587221
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 ...201323607480
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 ...201323742997
a novel lactococcal vaccine expressing a peptide from the m2 antigen of h5n2 highly pathogenic avian influenza a virus prolongs survival of vaccinated chickens.a cost-effective and efficacious influenza vaccine for use in commercial poultry farms would help protect against avian influenza outbreaks. current influenza vaccines for poultry are expensive and subtype specific, and therefore there is an urgent need to develop a universal avian influenza vaccine. we have constructed a live bacterial vaccine against avian influenza by expressing a conserved peptide from the ectodomain of m2 antigen (m2e) on the surface of lactococcus lactis (ll). chickens wer ...201323766929
prolonged excretion of a low-pathogenicity h5n2 avian influenza virus strain in the pekin duck.h5n2 strains of low-pathogenicity avian influenza virus (lpaiv) have been circulating for at least 17 years in some mexican chicken farms. we measured the rate and duration of viral excretion from pekin ducks that were experimentally inoculated with an h5n2 lpaiv that causes death in embryonated chicken eggs (a/chicken/mexico/2007). leghorn chickens were used as susceptible host controls. the degree of viral excretion was evaluated with real-time reverse transcriptase-polymerase chain reaction ( ...201323820212
genetic changes that accompanied shifts of low pathogenic avian influenza viruses toward higher pathogenicity in poultry.avian influenza viruses (aiv) of h5 and h7 subtypes exhibit two different pathotypes in poultry: infection with low pathogenic (lp) strains results in minimal, if any, health disturbances, whereas highly pathogenic (hp) strains cause severe morbidity and mortality. lpaiv of h5 and h7 subtypes can spontaneously mutate into hpaiv. ten outbreaks caused by hpaiv are known to have been preceded by circulation of a predecessor lpaiv in poultry. three of them were caused by h5n2 subtype and seven invol ...201323863606
complete genome sequence of avian influenza virus a/chicken/jiangsu/1001/2013(h5n2), demonstrating continuous reassortance of h5n2 in china.avian influenza virus a/chicken/jiangsu/1001/2013(h5n2) was identified from a healthy chicken in an eastern china poultry market. whole-genome analysis demonstrated that the h5n2 virus originated from a reassortance between a previous a/chicken/hebei/1102/2010(h5n2) virus and an endemic h5n1 virus. the results indicated that continuing reassortance of h5n2 has been occurring in domestic poultry of china.201323868124
excessive cytokine response to rapid proliferation of highly pathogenic avian influenza viruses leads to fatal systemic capillary leakage in chickens.highly pathogenic avian influenza viruses (hpaivs) cause lethal infection in chickens. severe cases of hpaiv infections have been also reported in mammals, including humans. in both mammals and birds, the relationship between host cytokine response to the infection with hpaivs and lethal outcome has not been well understood. in the present study, the highly pathogenic avian influenza viruses a/turkey/italy/4580/1999 (h7n1) (ty/italy) and a/chicken/netherlands/2586/2003 (h7n7) (ck/nl) and the low ...201323874602
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) ...201323875024
effect of passive immunization on immunogenicity and protective efficacy of vaccination against a mexican low-pathogenic avian h5n2 influenza virus.despite the use of vaccines, low-pathogenic (lp) h5n2 influenza viruses have continued to circulate and evolve in chickens in mexico since 1993, giving rise to multiple genetic variants. antigenic drift is partially responsible for the failure to control h5n2 influenza by vaccination; the contribution of maternal antibodies to this problem has received less attention.201323889740
genetic analysis of an h5n2 highly pathogenic avian influenza virus isolated from a chicken in a live bird market in northern vietnam in 2012.in august 2012, a/chicken/vietnam/oie-2215/2012 (h5n2) was isolated from a chicken in a live bird market (lbm) in northern vietnam. intravenous pathogenicity test revealed that this virus is highly pathogenic in chickens. the pa, ha, np and m, pb2 and na, and pb1 and ns genes of the isolate were phylogenetically closely related to those of a/duck/vietnam/oie-2202/2012 (h5n1) of clade 2.3.2.1, a/chicken/vietnam/oie-1611/2012 (h9n2) and a/chicken/vietnam/oie-2468/2012 (h9n2), respectively. all of ...201423986117
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 ...201324004822
[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 ...201624006632
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 ...201324043788
the characterization of low pathogenic avian influenza viruses isolated from wild birds in northern vietnam from 2006 to 2009.due to concerns that wild birds could possibly spread h5n1 viruses, surveillance was conducted to monitor the types of avian influenza viruses circulating among the wild birds migrating to or inhabiting in northern vietnam from 2006 to 2009. an h5n2 virus isolated from a eurasian woodcock had a close phylogenetic relationship to h5 viruses recently isolated in south korea and japan, suggesting that h5n2 has been shared between vietnam, south korea, and japan. an h9n2 virus isolated from a chines ...201324054984
emerging multiple reassortant h5n5 avian influenza viruses in ducks, china, 2008.three highly pathogenic h5n5 avian influenza viruses (hpai), a/duck/guangdong/wy11/2008 (wy11), a/duck/guangdong/wy19/2008 (wy19), and a/duck/guangdong/wy24/2008 (wy24) were isolated from ducks in southern china in april 2008. here, we characterized these viruses by performing sequencing and phylogenetic analyses of their viral genes, assessing their virulence in ducks and mice, and performing cross-protection experiments in chickens. sequence analysis revealed that the ha genes of these h5n5 vi ...201324080350
origin and molecular characterization of the human-infecting h6n1 influenza virus in taiwan.in june 2013, the first human h6n1 influenza virus infection was confirmed in taiwan. however, the origin and molecular characterization of this virus, a/taiwan/2/2013 (h6n1), have not been well studied thus far. in the present report, we performed phylogenetic and coalescent analyses of this virus and compared its molecular profile/characteristics with other closely related strains. molecular characterization of h6n1 revealed that it is a typical avian influenza virus of low pathogenicity, whic ...201324136722
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 ...201324146939
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 ...201324173647
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 ...201324256721
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. ...201324270383
environmental correlates of h5n2 low pathogenicity avian influenza outbreak heterogeneity in domestic poultry in italy.italy has experienced recurrent incursions of h5n2 avian influenza (ai) viruses in different geographical areas and varying sectors of the domestic poultry industry. considering outbreak heterogeneity rather than treating all outbreaks of low pathogenicity ai (lpai) viruses equally is important given their interactions with the environment and potential to spread, evolve and increase pathogenicity. this study aims at identifying potential environmental drivers of h5n2 lpai outbreak occurrence in ...201424466241
tracking socioeconomic vulnerability using network analysis: insights from an avian influenza outbreak in an ostrich production network.the focus of management in many complex systems is shifting towards facilitation, adaptation, building resilience, and reducing vulnerability. resilience management requires the development and application of general heuristics and methods for tracking changes in both resilience and vulnerability. we explored the emergence of vulnerability in the south african domestic ostrich industry, an animal production system which typically involves 3-4 movements of each bird during its lifetime. this syst ...201424498004
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 ...201424502341
cleavage site stability of egyptian highly pathogenic avian influenza viruses in backyard chickens during 2009-2011.two distinguishable subclades of h5n1 (classic and variant strains) are cocirculating among the poultry populations in egypt despite the intensive vaccination programs. a study to investigate the genetic relationship between avian influenza virus (aiv) isolates from backyard chickens in sharkia (2009-2011), subclades, and commercially available vaccines was carried out.201524560697
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 ...201424573857
emergence and evolution of avian h5n2 influenza viruses in chickens in taiwan.sporadic activity by h5n2 influenza viruses has been observed in chickens in taiwan from 2003 to 2012. the available information suggests that these viruses were generated by reassortment between a mexican-like h5n2 virus and a local enzootic h6n1 virus. yet the origin, prevalence, and pathogenicity of these h5n2 viruses have not been fully defined. following the 2012 highly pathogenic avian influenza (hpai) outbreaks, surveillance was conducted from december 2012 to july 2013 at a live-poultry ...201424623422
interspecies transmission of canine influenza virus h5n2 to cats and chickens by close contact with experimentally infected dogs.the novel h5n2 influenza virus, ca/sd/jt01/09, was isolated from the dog exhibiting respiratory signs in china in 2009. dog to dog transmission of the novel h5n2 was previously confirmed. but interspecies transmission of the virus between dogs and the other animals has still remained unclear. to determine whether the virus can be transmitted directly from dogs to cats and chickens, we conducted contact exposure experiments. susceptible cats and chickens were housed in the room which the novel h5 ...201424656135
mucosal vaccination with recombinant lactobacillus casei-displayed cta1-conjugated consensus matrix protein-2 (sm2) induces broad protection against divergent influenza subtypes in balb/c mice.to develop a safe and effective mucosal vaccine against pathogenic influenza viruses, we constructed recombinant lactobacillus casei strains that express conserved matrix protein 2 with (pgsa-cta1-sm2/l. casei) or without (pgsa-sm2/l. casei) cholera toxin subunit a1 (cta1) on the surface. the surface localization of the fusion protein was verified by cellular fractionation analyses, flow cytometry and immunofluorescence microscopy. oral and nasal inoculations of recombinant l. casei into mice re ...201424714362
influenza a(h5n2) virus antibodies in humans after contact with infected poultry, taiwan, 2012.six persons in taiwan who had contact with poultry infected with influenza a(h5n2) showed seroconversion for the virus by hemagglutinin inhibition or microneutralization testing. we developed an elisa based on nonstructural protein 1 of the virus to differentiate natural infection from cross-reactivity after vaccination; 2 persons also showed seroconversion by this test.201424750594
characterization of a low pathogenic avian influenza h5n2 virus isolated from a turkey breeder flock in manitoba, canada.in november 2010, an outbreak of avian influenza (ai) due to the h5n2 subtype virus occurred in a turkey breeder farm in northern manitoba, canada. the only clinical signs observed were depression, decrease in food consumption, and loss of egg production. the hemagglutinin (ha) cleavage (ha(0)) site of the isolated h5n2 virus was pqretr/glf, consistent with low pathogenic ai viruses. the intravenous pathogenicity index of this virus was zero. whole-genome sequencing of two isolates that originat ...201424758106
h5-based dna constructs derived from selected highly pathogenic h5n1 avian influenza virus induce high levels of humoral antibodies in muscovy ducks against low pathogenic viruses.h5 low pathogenic avian influenza virus (lpaiv) infection in domestic ducks is a major problem in duck producing countries. their silent circulation is an ongoing source of potential highly pathogenic or zoonotic emerging strains. to prevent such events, vaccination of domestic ducks might be attempted but remains challenging. currently licensed vector vaccines derived from h5n1 hpaiv possess clade 0, clade 2.2 or clade 2.3.4 ha sequences: selection of the best ha candidate inducing the largest ...201424762011
[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 ...201624772644
a chicken influenza virus recognizes fucosylated α2,3 sialoglycan receptors on the epithelial cells lining upper respiratory tracts of chickens.influenza viruses recognize sialoglycans as receptors. although viruses isolated form chickens preferentially bind to sialic acid α2,3 galactose (saα2,3gal) glycans as do those of ducks, chickens were not experimentally infected with viruses isolated from ducks. a chicken influenza virus, a/chicken/ibaraki/1/2005 (h5n2) (ck/ibr) bound to fucose-branched saα2,3gal glycans, whereas the binding towards linear saα2,3gal glycans was weak. on the epithelial cells of the upper respiratory tracts of chi ...201424889232
avian influenza virus with hemagglutinin-neuraminidase combination h8n8, isolated in russia.we report the genome sequence of an avian influenza virus (aiv) subtype h8n8, isolated in russia. the genome analysis shows that all genes belong to aiv eurasian lineages. the pb2 gene was similar to a mongolian low-pathogenic (lp) aiv h7n1 and a chinese high-pathogenic (hp) aiv h5n2.201424903874
extended transmission of two h5/h7 low pathogenic avian influenza viruses in chickens.transmission experiments are useful for investigating the mechanisms of low pathogenic notifiable avian influenza virus (lpnai) transmission. in this study, the hypothesis that inoculation-infected chickens are more infectious than contact-infected chickens was tested. to this end, extended transmission experiments with one h5n2 and one h7n1 lpaiv which had previously been characterized in a series of standard transmission experiments were conducted in specific pathogen-free (spf) chickens. for ...201524924291
broad cross-reactive epitopes of the h5n1 influenza virus identified by murine antibodies against the a/vietnam/1194/2004 hemagglutinin.there is an urgent need for a rapid diagnostic system to detect the h5 subtype of the influenza a virus. we previously developed monoclonal antibodies (mabs) against the h5 hemagglutinin (ha) for use in a rapid diagnostic kit. in this study, we determined the epitopes of the anti-h5 ha murine mabs om-b, ay-2c2, and yh-1a1. binding assays of the mabs to different strains of h5 has indicated that om-b and ay-2c2 cross-reacted with has from clades 1, 2.1.3.2, 2.2, and 2.3.4, whereas yh-1a1 failed t ...201424945805
bird to human transmission biases and vaccine escape mutants in h5n1 infections.the avian influenza a h5n1 virus occasionally infects humans, with high mortality rates. although all current human infections are from avian-to-human transmission, it has been shown that h5n1 can be evolved to transmit between mammals, and is therefore a pandemic threat. for h5n1 surveillance, it is of interest to identify the avian isolates most likely to infect humans. in this study, we develop a method to identify mutations significantly associated with avian to human transmission.201424988306
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 ...201424993748
adaptation of a natural reassortant h5n2 avian influenza virus in mice.it is reported that the h5n2 highly pathogenic avian influenza virus a/chicken/hebei/1102/2010 (hb10) is a natural reassortant between circulating h5n1 and endemic h9n2 influenza viruses. to evaluate the potential of its interspecies transmission, the wild-type hb10 was adapted in mice through serial lung passages. increased virulence was detectable in 5 sequential lung passages in mice and a highly virulent mouse-adapted strain (hb10-ma) with a 50% mouse lethal dose of 10(2.5) 50% egg infectiou ...201425037995
characterization of a novel highly pathogenic h5n2 avian influenza virus isolated from a duck in eastern china.during surveillance for avian influenza viruses (aivs) in live-poultry markets (lpms) in eastern china in 2013, one h5n2 aiv was isolated from a duck. phylogenetic analysis showed that the hemagglutinin of this strain belongs to clade 2.3.4 and received its genes from h5, h3 and h6 aivs of poultry in china. the virulence of this strain was examined in chickens and mice, and it was found to be highly pathogenic in chickens but demonstrated moderate pathogenicity in mice. these results suggest tha ...201425091744
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