nephrotropic properties demonstrated by a/chicken/alabama/75 (h4n8) following intravenous challenge of chickens.tissue tropism properties of a/chicken/alabama/75 (h4n8) were examined after intravenous inoculation of 5-week-old specific-pathogen-free chickens. from 14 clinically normal chickens euthanatized on days 1-20 postinoculation, the frequencies of virus recovery were highest for cloacal swabs (86%), bursal swabs (64%), and kidney tissues (64%) and lowest for tracheal swabs (14%), thymus tissues (14%), bone-marrow swabs (7%), and brain tissues (0%). evidence that the high frequency of virus recovery ...19921485875
re-evaluation of the pathogenicity of a/chicken/alabama/75 (h4n8) influenza virus.avian influenza (ai) virus a/chicken/alabama/7395/75 (h4n8), a putatively non-pathogenic virus associated with a self-limiting outbreak of severe disease in commercial layers, was selectively passed in chickens or in cell cultures and then in chickens to determine whether virus with increased pathogenicity would emerge. when 20 derivatives of the parental virus were each inoculated intranasally and intratracheally in leghorn hens, mortality rates ranged from zero (0/24) to 25% (6/24); mortality ...19921485880
assessing pathogenicity potential of waterfowl-origin type a influenza viruses in chickens.intravenous pathogenicity index (ivpi) tests on 29 wild duck-origin type a influenza viruses, two turkey-origin type a influenza viruses, and one chicken-origin type a influenza virus resulted in indices ranging from 0.0 to 0.49. most of the wild duck-origin viruses and the two turkey-origin viruses had indices of 0.0, indicating they are not pathogenic. six of the duck-origin viruses had indices ranging from 0.25 to 0.49, and the ivpi for a/chicken/alabama/75 (h4n8) was 0.49, indicating they ha ...19911827578
replication of avian influenza viruses in humans.volunteers inoculated with avian influenza viruses belonging to subtypes currently circulating in humans (h1n1 and h3n2) were largely refractory to infection. however 11 out of 40 volunteers inoculated with the avian subtypes, h4n8, h6n1, and h10n7, shed virus and had mild clinical symptoms: they did not produce a detectable antibody response. this was presumably because virus multiplication was limited and insufficient to stimulate a detectable primary immune response. avian influenza viruses c ...19911863223
enhancement of chicken lymphocyte activation and lymphokine release by avian influenza virus.we had previously found that inactivated avian influenza virus (aiv) could enhance the response of chicken lymphocytes to mitogen or antigen activation. an investigation into the possible mechanisms of this enhancement was undertaken. peripheral blood lymphocytes (pbl) were incubated with aiv expressing different hemagglutinin (ha) types (h1-h13) along with doses of concanavalin a (con a) which induce maximum (0.5 microgram) or submaximum (0.125 microgram) pbl activation. the lymphocyte activati ...19902086273
further evidence of the circulation of pmv-4 and influenza viruses with n2-1957 enzyme in the migratory the years 1980-1984, one paramyxovirus type 4 and 11 influenza viruses were isolated from cloacal swabs collected from migratory waterfowls in fed. rep. germany. one influenza virus of h4n8 subtype was isolated from swabs of commercial ducks collected at an abbatoir. seven of 10 influenza strains, isolated from mallard ducks and coot were identified as a mixture of 2-3 strains of h1, h4, and h5 subtype; 3 virus strains from the same locality relate antigenically to subtype h4 with enzyme sero ...19892576600
influence of dietary calcium stress on lethality of avian influenza viruses for laying chickens.the effect of calcium stress was studied in an attempt to reproduce lethal infections in laying chickens with a/chicken/alabama/75 (h4n8) influenza virus and with two nonpathogenic h5n2 influenza viruses from the 1983-84 outbreak in the eastern united states. hens were fed calcium-deficient or standard diets for 7 to 14 days; then the calcium-deficient feed was replaced with standard feed supplemented with ad libitum oyster shell, and both groups of hens were inoculated with virus. when hens wer ...19863028353
acute renal failure as the cause of death in chickens following intravenous inoculation with avian influenza virus a/chicken/alabama/7395/75 (h4n8).one-day-old and 5-week-old commercial leghorn, specific-pathogen-free leghorn, and broiler chickens were inoculated intravenously with either avian influenza virus isolate a/chicken/alabama/7395/75 (h4n8) (ck/al) or sterile diluent. ck/al infection resulted in a 44% mortality rate, reduced weight gains, and necrosis of proximal renal tubules and/or tubulointerstitial nephritis. the renal tubule necrosis was more severe and widespread in chickens that died than in chickens that were euthanatized. ...19948002884
pathological studies of a/chicken/alabama/7395/75 (h4n8) influenza virus in specific-pathogen-free laying hens.specific-pathogen-free laying hens were inoculated with avian influenza virus (aiv) a/chicken/alabama/7395/75 (h4n8) either intratracheally (it) or intravenously (iv). it inoculation produced a localized infection of the upper and lower respiratory tracts with lesions of tracheitis, bronchitis, airsacculitis, and pneumonia around the secondary bronchi. iv inoculation produced a systemic infection with major lesions of nephritis, interstitial pneumonia, salpingitis, and splenic and hepatic necros ...19948002896
influenza a viruses isolated from waterfowl in two wildlife management areas of pennsylvania.a survey was conducted at two wildlife management areas of pennsylvania (usa) to evaluate an antigen capture enzyme-linked immunosorbent assay (ac-elisa) for the detection of avian influenza viruses (aiv) in cloacal swabs from waterfowl and to determine the influenza a virus subtypes and the distribution of these viruses among waterfowl. we collected 330 cloacal swabs from hunter-killed waterfowl in the fall of 1990 and from cage-captured waterfowl in the summer of 1991. thirty-one hemagglutinat ...19958583635
pathogenicity of three avian influenza viruses for leghorn hens of different ages.pronounced host effects on clinical responses to influenza virus infection were not observed in any of seven trials in which young (26-43 weeks) and olf (65-94 weeks) leghorn hens were inoculated with low pathogenic subtype h5n2, h4n8, or h3n2 virus. in two of seven trials, where hens were infected with h4n8 or h3n2 virus, morbidity rates were slightly higher for old hens than for young hens. these observations indicate that host age effects of the severity of uncomplicated influenza virus infec ...19968883807
comparative pathology of chickens experimentally inoculated with avian influenza viruses of low and high pathogenicity.pathologic changes and distribution of viral antigen as determined by immunohistochemistry were compared among 4-wk-old specific-pathogen-free chickens inoculated intratracheally with avian influenza virus (aiv) isolates of either low or high pathogenicity. viruses of low pathogenicity, previously characterized as mildly pathogenic (mp), included a/chicken/pennsylvania/21525/83 (h5n2) (mp-penn) and a/chicken/alabama/7395/75 (h4n8) (mp-alab). viruses of high pathogenicity included a/chicken/penns ...19979087329
characterization of the influenza a virus gene pool in avian species in southern china: was h6n1 a derivative or a precursor of h5n1?in 1997, an h5n1 influenza virus outbreak occurred in chickens in hong kong, and the virus was transmitted directly to humans. because there is limited information about the avian influenza virus reservoir in that region, we genetically characterized virus strains isolated in hong kong during the 1997 outbreak. we sequenced the gene segments of a heterogeneous group of viruses of seven different serotypes (h3n8, h4n8, h6n1, h6n9, h11n1, h11n9, and h11n8) isolated from various bird species. the p ...200010864640
phylogenetic analyses of genes from south african lpai viruses isolated in 2004 from wild aquatic birds suggests introduction by eurasian 2004, south africa experienced its first recorded outbreak of a highly pathogenic notifiable avian influenza (hpnai) viral strain of the h5n2 subtype in ostriches in the eastern cape province. the traditional ostrich-farming areas in the western cape province report almost yearly outbreaks of low pathogenicity avian influenza (lpai) in ostriches, which is attributed to introduction by wild birds and certain climatic patterns. during the winter of 2004, lpai h3n8, h4n8, h5n2 and h5n1 avian inf ...200616447511
avian influenza a viruses in birds of the order psittaciformes: reports on virus isolations, transmission experiments and vaccinations and initial studies on innocuity and efficacy of oseltamivir in ovo.birds of the order psittaciformes are - besides chickens, turkeys and other birds - also susceptible to infection with avian influenza a viruses (aiv) and succumb following severe disease within one week. published data prove that various parakeets, amazons, cockatoos, african grey parrots and budgerigars (genera barnardius, psittacula, cacatua, eolophus, amazona, myiopsitta, psittacus and melopsittacus) were found dead following natural infections. natural infections of highly pathogenic avian ...200717724934
[complex environmental and virological monitoring in the primorye territory in 2003-2006].the paper presents the results of monitoring of viruses of western nile (wn), japanese encephalitis (je), tick-borne encephalitis (tbe), geta, influenza a, as well as avian paramicroviruses type i (virus of newcastle disease (nd)) and type 6 (apmv-6) in the primorye territory in 2003-2006. totally throughout the period, specific antibodies to the viruses were detected by neutralization test in wild birds (7.3%, wn; 8.0%, geta; 0.7% batai; 2.8%, alpine hare (lepus timidus); by hemagglutination-in ...200718041224
efficacy of avridine and liposomes as adjuvants for avian influenza virus antigens in turkeys.four-week-old turkeys were vaccinated with h4n8, h5n2 and h7n3 inactivated avian influenza viruses (aiv) in one of the following adjuvants: avridine, positively charged liposomal avridine, liposomal avridine with covalent attachment to the aiv antigens and oil-emulsion; and without any adjuvant. two vaccinations were given at a 4-week interval. antibody concentrations in sera and in respiratory lavages were measured over a period of 8 weeks. the turkeys responded with high cumulative geometric m ...199218670935
[infection of pigs with influenza a/h4 and a/h5 viruses isolated from wild birds on the territory of russia].pigs were intranasally infected with avian influenza a/h5 (h5n1, h5n3) and a/h4 (h4n6, h4n8) viruses in mono- and coinfection. infection with both apathogenic and pathogenic strains caused no clinical manifestations. a virus and/or fragments of its genome retained in nasopharyngeal fluid as long as 6-8 days after infection. during monoinfection, the structure of the hemagglutinin (ha) receptor site of isolates from the pigs infected with a/h5n1 strains (a/chicken/kurgan/3/2005, a/duck/russia/535 ...200819172904
comparison of cloacal and oropharyngeal samples for the detection of avian influenza virus in wild birds.this study was conducted to compare oropharyngeal (op) and cloacal samples of wild birds (n = 137) for the detection and isolation of avian influenza virus (aiv). a total of 39 (28.5%) cloacal and 85 (62.0%) op samples were positive for aiv by real-time reverse transcription-pcr (rrt-pcr). the aiv nucleic acid was detected in both cloacal and op samples from 27 (19.7%) birds, in cloacal samples only from 12 (8.8%) birds, and in op samples only from 58 (42.3%) birds. thus, a total of 97 (70.8%) b ...201020408409
a nanobeads amplified qcm immunosensor for the detection of avian influenza virus a potential pandemic threat to human health, there has been an urgent need for rapid detection of the highly pathogenic avian influenza (ai) h5n1 virus. in this study, magnetic nanobeads amplification based quartz crystal microbalance (qcm) immunosensor was developed as a new method and application for ai h5n1 virus detection. polyclonal antibodies against ai h5n1 virus surface antigen ha (hemagglutinin) were immobilized on the gold surface of the qcm crystal through self-assembled monolayer ...201121536419
H4N8 subtype avian influenza virus isolated from shorebirds contains a unique PB1 gene and causes severe respiratory disease in mice.H4N8 subtype avian influenza viruses were isolated from shorebirds in eastern Hokkaido. All the isolates shared >99.7% nucleotide homology, and all the viral genes except for PB1 were highly related to those of A/red-necked stint/Australia/1/04. Thus, the isolates were regarded as PB1 reassortants. The most similar PB1 gene was identified in A/mallard/New Zealand/1615-17/04 (H4N6) with nucleotide homology of 90.9%. BALB/c mice intranasally inoculated with the H4N8 isolates developed severe respi ...201122192630
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
bio-nanogate controlled enzymatic reaction for virus sensing.the objective of this study was to develop an aptamer-based bifunctional bio-nanogate, which could selectively respond to target molecules, and control enzymatic reaction for electrochemical measurements. it was successfully applied for sensitive, selective, rapid, quantitative, and label-free detection of avian influenza viruses (aiv) h5n1. a nanoporous gold film with pore size of ~20 nm was prepared by a metallic corrosion method, and the purity was checked by energy-dispersive x-ray spectrosc ...201525212377
presence of avian influenza viruses in waterfowl and wetlands during summer 2010 in california: are resident birds a potential reservoir?although wild waterfowl are the main reservoir for low pathogenic avian influenza viruses (lpaiv), the environment plays a critical role for the circulation and persistence of aiv. lpaiv may persist for extended periods in cold environments, suggesting that waterfowl breeding areas in the northern hemisphere may be an important reservoir for aiv in contrast to the warmer southern wintering areas. we evaluated whether southern wetlands, with relatively small populations (thousands) of resident wa ...201222328934
low-pathogenic avian influenza viruses in wild house mice.avian influenza viruses are known to productively infect a number of mammal species, several of which are commonly found on or near poultry and gamebird farms. while control of rodent species is often used to limit avian influenza virus transmission within and among outbreak sites, few studies have investigated the potential role of these species in outbreak dynamics.201222720076
isolation and characterization of influenza a viruses from environmental water at an overwintering site of migratory birds in japan.the izumi plain in kagoshima prefecture, japan, is an overwintering site of more than 10,000 cranes. the wet paddy areas are artificially created to provide roosting sites for the cranes every winter. since wild ducks, known to be a natural reservoir of influenza a viruses, also overwinter in this area, the cranes' roost water likely serves as a source of influenza a virus infection. to assess this potential risk, we collected 126 water samples from the cranes' roost in the 2012/2013 winter seas ...201526392284
low pathogenic influenza a viruses in north american diving ducks contribute to the emergence of a novel highly pathogenic influenza a(h7n8) virus.introductions of low pathogenic avian influenza (lpai) viruses of subtypes h5 and h7 into poultry from wild birds have the potential to mutate to highly pathogenic avian influenza (hpai), but such viruses' origins are often unclear. in january 2016, a novel h7n8 hpai virus caused an outbreak in turkeys in indiana, usa. to determine the virus's origin, we sequenced genomes of 441 wild bird-origin influenza a viruses (iavs) from north america and subjected them to evolutionary analyses. results sh ...201728202755
lung cytokine gene expression is correlated with increased severity of disease in a novel h4n8 influenza virus isolated from shorebirds.the lung cytokine gene expression profiles of mice infected with 2 strains of h4n8 viruses isolated from shorebirds and reference h4 viruses from ducks are compared. major differences between the two h4n8 strains of shorebirds, one of which causes a severe respiratory disease in mice, are in the pb1 and ns1 genes. in mice with h4n8 virus induced pneumonia, overall expression of tnf-α, il-6 and il-12 genes was markedly higher than in mice infected with other h4 viruses tested, although gene expre ...201323759687
complete genome sequence of an avian-like h4n8 swine influenza virus discovered in southern china.we report here the complete genomic sequence of an avian-like h4n8 swine influenza virus containing an h5n1 avian influenza virus segment from swine in southern china. phylogenetic analyses of the sequences of all eight viral rna segments demonstrated that these are wholly avian influenza viruses of the asia lineage. to our knowledge, this is the first report of interspecies transmission of an avian h4n8 influenza virus to domestic pigs under natural conditions.201222879613
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