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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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
the threat of highly pathogenic avian influenza h5: will h5n2 infections occur in humans? 201222901729
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
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
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
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
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
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
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
[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
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
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
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
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
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
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
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
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
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
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
vaccination and acute phase mediator production in chickens challenged with low pathogenic avian influenza virus; novel markers for vaccine efficacy?methods to determine vaccine efficacy of low pathogenic avian influenza (lpai) isolates are limited in poultry because experimental infections with lpai virus in specific pathogen free chickens rarely causes clinical disease. the most commonly used method to compare lpai vaccine efficacy is to quantify viral shedding after challenge, but it is time and labor intensive. therefore, we sought alternative methods to demonstrate vaccine efficacy, and examined whether vaccination of chickens affected ...201222394994
[the generation and characteristics of reassortant influenza a virus with h5 hemagglutinin and other genes from the apathogenic virus h6n2].the experimental reassortant vaccine strain vn-gull (h5n2) containing h5 hemagglutinin (ha) with a removed polybasic site in the connecting peptide and other genes from the apathogenic h6n2 virus a/gull/moscow/3100/2006 (gull/m) was obtained using a two-step protocol. at step 1, the reassortant with ha of a/vietnam/1203/04-pr8/ cdc-rg and other genes from cold-adapted a/leningrad/17/47 (vn-len) viruses was generated due to selection with antibody to h2n2 at 26 degrees c. at step 2, the reassorta ...201122359942
distribution of avian influenza h5n1 viral rna in tissues of ai-vaccinated and unvaccinated contact chickens after experimental infection.avian influenza due to highly pathogenic avian influenza (hpaiv) h5n1 virus is not a food-borne illness but a serious panzootic disease with the potential to be pandemic. in this study, broiler chickens were vaccinated with commercial h5n1 or h5n2 inactivated vaccines prior to being challenged with an hpaiv h5n1 (clade 2.2.1 classic) virus. challenged and non-challenged vaccinated chickens were kept together, and unvaccinated chickens served as contact groups. post-challenge samples from skin an ...201222350650
cloned cdna of a/swine/iowa/15/1930 internal genes as a candidate backbone for reverse genetics vaccine against influenza a viruses.reverse genetics viruses for influenza vaccine production usually utilize the internal genes of the egg-adapted a/puerto rico/8/34 (pr8) strain. this egg-adapted strain provides high production yield in embryonated eggs but does not necessarily give the best yield in mammalian cell culture. in order to generate a reverse genetics viral backbone that is well-adapted to high growth in mammalian cell culture, a swine influenza isolate a/swine/iowa/15/30 (h1n1) (rg1930) that was shown to give high y ...201222230579
salmonella flagellin enhances mucosal immunity of avian influenza vaccine in chickens.flagellin, a bioactive toll-like receptor (tlr) 5 ligand, may trigger the innate immunity that in turn is important for subsequent adaptive immune responses. in the present study, the adjuvant effects of the monomeric and polymeric forms of salmonella flagellin (mflic and pflic, respectively) were examined in specific-pathogen free (spf) chickens immunized intramuscularly (i.m.) or intranasally (i.n.) with formalin-inactivated avian influenza virus (aiv) h5n2 vaccines. results showed that mflic ...201122226542
development of a recombinant elisa using yeast (pichia pastoris)-expressed polypeptides for detection of antibodies against avian influenza a subtype h5.two truncated sequences (designated p1 and rha1) of influenza a virus subtype h5 haemagglutinin (ha) were cloned and expressed in yeast pichia pastoris (p. pastoris). these polypeptides were used in an indirect recombinant elisa (relisa) for detection of h5 antibodies in poultry. serum samples obtained from broiler chickens vaccinated with commercial inactivated vaccine (h5n2) and control negative sera from non-vaccinated chickens against influenza were tested using rp1-elisa, rha1-elisa, whole ...201122197190
Isolation, identification, and phylogenetic analysis of reassortant low-pathogenic avian influenza virus H3N1 from Pakistan.During routine avian influenza surveillance in Pakistan, a low-pathogenic avian influenza virus (LPAI) subtype H3N1 was isolated for the first time from domestic chickens. The higher seroprevalence of H3N1 was recorded in both commercial and domestic poultry in ecological zones of Pakistan where the geographical proximity with neighboring countries and attractive birding sites provide better opportunities for frequent movements of wild and migratory birds, and their intermingling with the local ...201222184438
rapid and specific influenza virus detection by functionalized magnetic nanoparticles and mass spectrometry.abstract:201122088100
Genetic characterization of a novel influenza A virus H5N2 isolated from a dog in China.An influenza virus, A/canine/Shandong/JT01/2009, has been isolated from a dog exhibiting classical flu signs in China. HAI and NAI assays subtyped A/canine/Shandong/JT01/2009 as a H5N2 like virus. Phylogenetic reconstructions indicated strong relationships with viruses from various hosts and dispersed geographic locations. These analyses indicate A/canine/Shandong/JT01/2009 is a novel virus generated by complex reassortment of the viral segments.201122033043
Coexpression of avian influenza virus H5 and N1 by recombinant Newcastle disease virus and the impact on immune response in chickens.To analyze the contribution of neuraminidase (NA) toward protection against avian influenza virus (AIV) infection, three different recombinant Newcastle disease viruses (NDVs) expressing hemagglutinin (HA) or NA, or both, of highly pathogenic avian influenza virus (HPAIV) were generated. The lentogenic NDV Clone 30 was used as backbone for the insertion of HA of HPAIV strain A/chicken/Vietnam/P41/05 (H5N1) and NA of HPAIV strain A/duck/Vietnam/TG24-01/05 (H5N1). The HA was inserted between the g ...201122017039
influenza-a viruses in ducks in northwestern minnesota: fine scale spatial and temporal variation in prevalence and subtype diversity.waterfowl from northwestern minnesota were sampled by cloacal swabbing for avian influenza virus (aiv) from july-october in 2007 and 2008. aiv was detected in 222 (9.1%) of 2,441 ducks in 2007 and in 438 (17.9%) of 2,452 ducks in 2008. prevalence of aiv peaked in late summer. we detected 27 aiv subtypes during 2007 and 31 during 2008. ten hemagglutinin (ha) subtypes were detected each year (i.e., h1, 3-8, and 10-12 during 2007; h1-8, 10 and 11 during 2008). all neuraminidase (na) subtypes were d ...201121931636
Influence of maternal immunity on vaccine efficacy and susceptibility of one day old chicks against Egyptian highly pathogenic avian influenza H5N1.In Egypt, continuous circulation of highly pathogenic avian influenza (HPAI) H5N1 viruses of clade 2.2.1 in vaccinated commercial poultry challenges strenuous control efforts. Here, vaccine-derived maternal AIV H5 specific immunity in one-day old chicks was investigated as a factor of vaccine failure in long-term blanket vaccination campaigns in broiler chickens. H5 seropositive one-day old chicks were derived from breeders repeatedly immunized with a commercial inactivated vaccine based on the ...201121920677
[evaluation of immunogenicity and safety of 2 immunizations with allantoic intranasal live influenza vaccine ultragrivac].evaluate reactogenicity, safety and immunogenicity in phase 2 clinical trials of 2 immunization schedules with ultragrivac--an allantoic intranasal life influenza vaccine based on a/17/ duck/potsdam/86/92 [17/h5] reassortant strain.201121916043
evaluation study of a portable impedance biosensor for detection of avian influenza virus.current methods for detection of avian influenza virus (aiv) based on virus culture and rt-pcr are well established, but they are either time consuming or require specialized laboratory facilities and highly trained technicians. a simple, rapid, robust, and reliable test, suitable for use in the field or at the patient's bedside, is urgently needed. in this study, the performance of a newly developed portable impedance biosensor was evaluated by comparison with real-time reverse transcriptase pc ...201121872621
memory t-cell immune response in healthy young adults vaccinated with live attenuated influenza a(h5n2) vaccine.cellular immune responses of both cd4 and cd8 memory/effector t cells were evaluated in healthy young adults who received two doses of live attenuated influenza a(h5n2) vaccine. the vaccine was developed by reassortment of non-pathogenic avian a/duck/potsdam/1402-6/68 (h5n2) and cold-adapted a/leningrad/134/17/57 (h2n2) viruses. t-cell responses were measured by standard methods of intracellular cytokine staining of ifnγ-producing cells and a novel trap-assay based on the trogocytosis phenomenon ...201121813657
[immunogenicity of influenza virus h5n2 vaccine strain samples produced by roller cultivation in media with plant derived components].study in cba line mice of immunogenicity of cold adapted reassortant influenza virus h5n2 vaccine strain samples produced in rollers in mdck and vero cell cultures by using plant derived components.201121812141
humoral antibody responses to different h5n1 and h5n2 vaccination regimes: implications for the development of autogenously based vaccines.whereas h5n1 vaccine and several h5n2 vaccines are commercially available and are used to control h5n1 outbreaks in some endemic countries, infections hit many vaccinated flocks. the following study was conducted to compare the efficacy of such vaccines and to assess their potential induction of antibodies against the haemagglutinin of local h5n1 isolate after single vaccination. the possible beneficiary effect of booster dose at different intervals was screened for both h5n1 vaccine as well as ...201121752557
multiple dose vaccination with heterologous h5n2 vaccine: immune response and protection against variant clade 2.2.1 highly pathogenic avian influenza h5n1 in broiler breeder chickens.circulation of an antigenically variant lineage of highly pathogenic avian influenza (hpai) h5n1 virus in chicken breeder flocks in egypt is a continuing problem. the protective efficacy of multiple repeated vaccinations using the currently available h5n2 vaccines is unclear. here, broiler breeder chickens were vaccinated at weeks 6, 12 and 18 with an inactivated h5n2 commercial vaccine. hi-titer against an egyptian h5n1 field isolate of classic clade 2.2.1 (egycls/h5n1) were significantly lower ...201121745517
thermal inactivation of avian influenza virus and newcastle disease virus in a fat-free egg product.high-pathogenicity avian influenza (hpai) virus, low-pathogenicity avian influenza (lpai) virus, virulent newcastle disease virus (vndv) and low-virulent newcastle disease virus (lndv) can be present on the eggshell surface, and hpai viruses and vndv can be present in the internal contents of chicken eggs laid by infected hens. with the increase in global trade, egg products could present potential biosecurity problems and affect international trade in liquid and dried egg products. therefore, t ...201121740719
measurement of enzymatic activity and specificity of human and avian influenza neuraminidases from whole virus by glycoarray and maldi-tof mass spectrometry.influenza neuraminidases hydrolyze the ketosidic linkage between n-acetylneuraminic acid and its adjacent galactose residue in sialosides. this enzyme is a tetrameric protein that plays a critical role in the release of progeny virions. several methods have been described for the determination of neuraminidase activity, usually based on colorimetric, fluorescent, or chemiluminescent detection. however, only a few of these tests allow discrimination of the sialyl-linkage specificity (i.e., α2-3- ...201121739555
avian influenza viruses infect primary human bronchial epithelial cells unconstrained by sialic acid +¦2,3 residues.avian influenza viruses (aiv) are an important emerging threat to public health. it is thought that sialic acid (sia) receptors are barriers in cross-species transmission where the binding preferences of aiv and human influenza viruses are sias +¦2,3 versus +¦2,6, respectively. in this study, we show that a normal fully differentiated, primary human bronchial epithelial cell model is readily infected by low pathogenic h5n1, h5n2 and h5n3 aiv, which primarily bind to sia +¦2,3 moieties, and repli ...201121731666
expression of duck ccl19 and ccl21 and ccr7 receptor in lymphoid and influenza-infected tissues.ducks are the natural host and reservoir of influenza viruses. we are interested in their immune responses to these viruses, to understand host-pathogen interactions and to develop effective agricultural vaccines. we identified duck homologues of the chemokines ccl19 and ccl21 and cloned their cognate receptor, ccr7. conservation of key features, and expression in lymphoid tissues suggests that these chemokines are the direct orthologues of their mammalian counterparts. mammalian ccl19 and ccl21 ...201121704378
development of influenza vaccine production capacity by the government pharmaceutical organization of thailand: addressing the threat of an influenza pandemic.in 2005, a year after highly pathogenic avian influenza outbreaks in thailand, the thai government issued a national strategy plan for pandemic influenza preparedness, a major objective of which was the domestic production of seasonal influenza vaccine. it was considered that sustained influenza vaccine production was the best guarantee of a pandemic vaccine in the event of a future pandemic. the government decided to provide funds to establish an industrial-scale influenza vaccine production pl ...201121684425
complete protection against a h5n2 avian influenza virus by a dna vaccine expressing a fusion protein of h1n1 ha and m2e.most influenza vaccines target hemagglutinin (ha) in order to protect the host against infection. however, theses vaccines are strain-specific due to major antigenic variations of ha. since it is difficult to predict epidemic and pandemic strains of influenza virus, the development of effective vaccines against divergent influenza viruses is urgently needed. although m2e-based vaccines are associated with weaker protection than ha-based vaccines that induce neutralizing antibodies against challe ...201121664216
[use of plant-origin components in roller cultivation of vaccine reassortant influenza virus strain h5n2].to study the optimal conditions for roller cultivation of cold-adapted reassortant vaccine strain of influenza virus a/17/duck/ potsdam/86/92 (h5n2) in mdck and vero cell cultures grown on nutrient medium based on soy and rice flour hydrolysates obtained using trypsin and bromeline.201121598624
immunoadjuvant efficacy of plasmids with multiple copies of a cpg motif coadministrated with avian influenza vaccine in chickens.unmethylated cpg motifs are capable of evoking a range of immunostimulatory effects in vertebrates and have tremendous potential to be used as therapeutic agents and adjuvants. this particular type of cpg motif has been demonstrated to be an excellent immune adjuvant mediated by toll-like receptor 9 (tlr9) in various mammalian vaccines; however, only a few studies confirm its efficacy in avian vaccines. in the present study, immunomodulatory activities of plasmids with various copy numbers of a ...201121557981
the adjuvant effect of sophy beta-glucan to the antibody response in poultry immunized by the avian influenza a h5n1 and h5n2 vaccines.avian influenza virus vaccines produced in oil-emulsified inactivated form with antigen content of at least 160 hemagglutinin units (hau) induced immunity in birds. however, in addition to enhancing the effect of the adjuvant(s), other additional supplemented biological compounds included in inactivated vaccines could produce higher levels of antibody. we examined in chickens, vietnamese ducks, and muscovy ducks the adjuvant effect of sophy beta-glucan (sbg), a beta-1,3-1,6 glucan produced by th ...201121532325
avian influenza mucosal vaccination in chickens with replication-defective recombinant adenovirus vaccine.we evaluated protection conferred by mucosal vaccination with replication-competent adenovirus-free recombinant adenovirus expressing a codon-optimized avian influenza (ai) h5 gene from a/turkey/wi/68 (adtw68.h5ck). commercial, layer-type chicken groups were either singly vaccinated ocularly at 5 days of age, singly vaccinated via spray at 5 days of age, or ocularly primed at 5 days and ocularly boosted at 15 days of age. only chickens primed and boosted via the ocular route developed ai systemi ...201121500634
transmission of avian influenza a viruses among species in an artificial barnyard.waterfowl and shorebirds harbor and shed all hemagglutinin and neuraminidase subtypes of influenza a viruses and interact in nature with a broad range of other avian and mammalian species to which they might transmit such viruses. estimating the efficiency and importance of such cross-species transmission using epidemiological approaches is difficult. we therefore addressed this question by studying transmission of low pathogenic h5 and h7 viruses from infected ducks to other common animals in a ...201121483843
unusual h5n2 avian influenza virus escapes current detection. 201121471334
[protective activity of immunovac-vp-4 vaccine against avian influenza virus h5n2 administered by different methods].to experimentally assess protective effect of immunovac-vp-4 vaccine against avian influenza virus h5n2. materials and methods. immunization of mice with polycomponent vaccine immunovac-vp-4 was performed using oral or mucosal route of administration (intranasally, orally, and with combined nasal-oral method). immunized mice were inoculated intranasally by influenza virus h5n2 adapted for mice. survival of mice in experimental and control (intact) groups was assessed daily during 14 days. surviv ...201121446167
efficacy of avian influenza vaccine in poultry: a meta-analysis.vaccination is an effective method for controlling avian influenza (ai), especially in countries with endemic infection. this study conducted a bayesian meta-analysis to evaluate the efficacy of ai vaccines in chickens. we included both inactivated and recombinant fowlpox virus expressing h5 (rfpv-h5) vaccine studies that used specific-pathogen-free chickens where outcomes against the h5n1 or h5n2 ai viruses were measured. vaccine efficacy was evaluated by protection from mortality, protection f ...201021313840
a low pathogenic h5n2 influenza virus isolated in taiwan acquired high pathogenicity by consecutive passages in chickens.h5n2 viruses were isolated from cloacal swab samples of apparently healthy chickens in taiwan in 2003 and 2008 during surveillance of avian influenza. each of the viruses was eradicated by stamping out. the official diagnosis report indicated that the intravenous pathogenicity indexes (ivpis) of the isolates were 0.00 and 0.89, respectively, indicating that these were low pathogenic strains, although the hemagglutinin of the strain isolated in 2008 (taiwan08) had multibasic amino acid residues a ...201121301183
further evidence of antigenic drift and protective efficacy afforded by a recombinant hvt-h5 vaccine against challenge with two antigenically divergent egyptian clade 2.2.1 hpai h5n1 strains.in this study, we have compared the protection afforded by a recombinant turkey herpesvirus vaccine expressing the h5 gene from a clade 2.2 h5n1 strain (rhvt-h5) and a mexican-origin h5n2 inactivated vaccine, alone or in combination, against two antigenically divergent h5n1 egyptian strains isolated in 2007 and 2008. our results confirm the existence of a major antigenic drift among the egyptian h5n1 strains such that, although protection against the "classical" 2007 hpai h5n1 egyptian strain co ...201121292007
association of mx1 asn631 variant alleles with reductions in morbidity, early mortality, viral shedding, and cytokine responses in chickens infected with a highly pathogenic avian influenza virus.myxovirus-resistance (mx) proteins are produced by host cells in response to type i interferons, and some members of the mx gene family in mammals have been shown to limit replication of influenza and other viruses. according to an early report, chicken mx1 variants encoding asn at position 631 have antiviral activity, whereas variants with ser at 631 lack activity in experiments evaluating mx1 complementary dna (cdna) expressed ectopically in a cell line. we evaluated whether the mx1 631 dimorp ...201121286706
use of a tetanus toxoid marker to allow differentiation of infected from vaccinated poultry without affecting the efficacy of a h5n1 avian influenza virus vaccine.tetanus toxoid (tt) was assessed as a positive marker for avian influenza (ai) virus vaccination in chickens, in a vaccination and challenge study. chickens were vaccinated twice with inactivated ai h5n2 virus vaccine, and then challenged three weeks later with highly pathogenic ai h5n1 virus. vaccinated chickens were compared with other groups that were either sham-vaccinated or vaccinated with virus with the tt marker. all sham-vaccinated chickens died by 36 hours postinfection, whereas all va ...201021257485
reassortant low-pathogenic avian influenza h5n2 viruses in african wild birds.to investigate the presence and persistence of avian influenza virus in african birds, we monitored avian influenza in wild and domestic birds in two different regions in nigeria. we found low-pathogenic avian influenza (lpai) h5n2 viruses in three spur-winged geese (plectropterus gambensis) in the hadejia-nguru wetlands. phylogenetic analyses revealed that all of the genes, except the non-structural (ns) genes, of the lpai h5n2 viruses were more closely related to genes recently found in wild a ...201121248176
highly pathogenic avian influenza virus h5n1 from egypt escapes vaccine-induced immunity but confers clinical protection against a heterologous clade 2.2.1 egyptian isolate.the poultry populations of egypt are endemically infected by highly pathogenic avian influenza viruses (hpaiv) of subtype h5n1. vaccination was chosen as an auxiliary tool to control hpaiv in poultry. potency of commercial vaccines regarding emerging variants is under discussion. in the current study efficacy of four different inactivated whole h5 virus vaccines representing different sublineages of hpaiv h5n1 were tested in chickens against challenge viruses currently co-circulating in egypt an ...201121244859
protective efficacy of h5 inactivated vaccines in meat turkey poults after challenge with egyptian variant highly pathogenic avian influenza h5n1 virus.in contrast to chickens, there is a paucity of information on the potency of h5 vaccines to protect turkeys against the highly pathogenic avian influenza (hpai) h5n1 virus infections. in this study, 4 groups, 10 turkey poults each, were vaccinated at seven days old with one of h5n2 or h5n1 commercial vaccines or one of two prepared h5n1 vaccines from a local egyptian variant hpai h5n1 (egyvar/h5n1) strain. at 35 days age, all vaccinated and 10 non vaccinated birds were challenged intranasal with ...201021236607
impact of antigenic and genetic drift on the serologic surveillance of h5n2 avian influenza viruses.serologic surveillance of avian influenza (ai) viruses is carried out by the hemagglutination inhibition (hi) test using reference reagents. this method is recommended by animal health organizations as a standard test to detect antigenic differences (subtypes) between circulating influenza virus, vaccine- and/or reference- strains. however, significant discrepancies between reference antisera and field isolates have been observed during serosurveillance of influenza a viruses in pig and poultry ...201021172021
differential effects of ns1 proteins of human pandemic h1n1/2009, avian highly pathogenic h5n1, and low pathogenic h5n2 influenza a viruses on cellular pre-mrna polyadenylation and mrna translation.the nonstructural protein ns1 of influenza a virus blocks the development of host antiviral responses by inhibiting polyadenylation of cellular pre-mrna. ns1 also promotes the synthesis of viral proteins by stimulating mrna translation. here, we show that recombinant ns1 proteins of human pandemic h1n1/2009, avian highly pathogenic h5n1, and low pathogenic h5n2 influenza strains differentially affected these two cellular processes: ns1 of the two avian strains, in contrast to ns1 of h1n1/2009, s ...201021163951
supplemental treatment of air in airborne infection isolation rooms using high-throughput in-room air decontamination units.evidence has recently emerged indicating that in addition to large airborne droplets, fine aerosol particles can be an important mode of influenza transmission that may have been hitherto underestimated. furthermore, recent performance studies evaluating airborne infection isolation (aii) rooms designed to house infectious patients have revealed major discrepancies between what is prescribed and what is actually measured.201021095042
surveillance and identification of influenza a viruses in wild aquatic birds in the crimea, ukraine (2006-2008).the ecology of avian influenza (ai) viruses in wild aquatic birds of asia is poorly understood, especially for the h5n1 high pathogenicity ai (hpai) viruses. from march 2006 through november 2008, 20 ai viruses were isolated in the crimea region of ukraine with an overall frequency of virus recovery of 3.3%. all the viruses were isolated from three species of dabbling ducks: mallard (anas platyrhynchos), wigeon (anas penelope), and garganey (anas querquedula), making the frequency of virus recov ...201020945793
myd88 signaling is indispensable for primary influenza a virus infection but dispensable for secondary infection.recent studies have revealed that innate immunity is involved in the development of adaptive immune responses; however, its role in protection is not clear. in order to elucidate the exact role of toll-like receptor (tlr) or rig-i-like receptor (rlr) signaling on immunogenicity and protective efficacy against influenza a virus infection (a/pr/8/34 [pr8]; h1n1), we adapted several innate signal-deficient mice (e.g., trif(-/-), myd88(-/-), myd88(-/-) trif(-/-), tlr3(-/-) tlr7(-/-), and ips-1(-/-)) ...201020943980
immunogenicity and protective efficacy of a dna vaccine encoding a chimeric protein of avian influenza hemagglutinin subtype h5 fused to cd154 (cd40l) in pekin ducks.the potential of cd154 (cd40l) as a powerful immunological adjuvant has been shown in various strategies. in this study we examine the immunogenicity and protective efficacy of a cd40-targeting avian influenza hemagglutinin (ha) subunit dna vaccine in ducks. dna constructs encoded the ectodomain of the ha protein of lpai a/mallard/bc/373/2005 (h5n2) with or without fusion to the ectodomain of duck cd154. cd40-targeting significantly accelerated and enhanced humoral responses to the vector-encode ...201020937323
a highly sensitive immuno-pcr assay for detection of h5n1 avian influenza virus.with an aim at detecting the ultra-low concentration of avian influenza virus (aiv), a highly sensitive hybrid assay based on immunology and polymerase chain reaction was developed. the topyield microtiter plates were coated with ten-fold serial dilutions of h5n1 subtype aiv ranging from 10 eid(50 )ml(-1)~10(-4) eid(50) ml(-1),which was recognized by mouse anti-aiv h5 monoclonal antibody (mab) that was directly linked with reporter dna using a heterobifunctional cross-linker. after extensive was ...201120862550
[protective properties of candidate genetically engineered vaccines against avian influenza viruses constructed on the basis of recombinant adenoviral vectors].to design and study the properties of candidate vaccines against avian influenza based on recombinant adenoviral vectors expressing h5 hemagglutinin.201020734718
longitudinal 2 years field study of conventional vaccination against highly pathogenic avian influenza h5n1 in layer hens.a licensed, inactivated vaccine based on a low pathogenic avian influenza virus strain (h5n2) was evaluated in layer hens kept under field conditions during a 2-year period. vaccine efficacy was investigated by specific antibodies and by challenge-contact experiments using highly pathogenic avian influenza viruses (hpaiv) h5n1. basic immunization with two applications induced clinical protection. virus excretion by vaccinated hens was significantly reduced compared to non-vaccinated controls; tr ...201020727963
surveillance of avian influenza virus in wild bird fecal samples from south korea, 2003-2008.we analyzed the results from nationwide surveillance of avian influenza (ai) from birds in south korea's major wild bird habitats and the demilitarized zone of south korea, 2003-2008. of 28,214 fecal samples analyzed, 225 yielded influenza viruses, for a prevalence of 0.8%. hemagglutinin (ha) subtypes h1-h12 and all nine neuraminidase (na) subtypes were detected. the dominant ha subtypes were h6, h1, and h4, and the most common na subtypes were n2, n1, and n6. among the 38 ha/na subtype combinat ...201020688693
evaluation of the xpert flu a panel nucleic acid amplification-based point-of-care test for influenza a virus detection and pandemic h1 subtyping.influenza antigenic point-of-care (poc) tests are too insensitive for individual reliable diagnosis of influenza virus infections without additional laboratory confirmation. molecular poc tests could be a valuable alternative.201020674478
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