avian cells expressing the murine mx1 protein are resistant to influenza virus infection.the cdna encoding the murine mx1 protein, a mediator of resistance to influenza virus, was inserted into a replication-competent avian retroviral vector in either the sense (referred to as mx+) or the antisense (referred to as mx-) orientation relative to the viral structural genes. both vectors produced virus retaining the mx insert (mx recombinant viruses referred to as mx+ and mx-) following transfection into chicken embryo fibroblasts (cef). mx protein of the appropriate size and nuclear loc ...19911989389
effects of ph, temperature, and salinity on persistence of avian influenza viruses in water.the combined effects of water temperature, salinity, and ph on persistence of avian influenza virus (aiv) were evaluated in a model distilled-water system using three isolates from ducks sampled in cameron parish, louisiana. variables were tested within the ranges normally associated with surface water. differences were detected between temperature (17 c and 28 c), ph (6.2, 7.2, 8.2), and salinity (0 ppt and 20 ppt), with a strong interactive effect observed between ph and salinity. estimated pe ...19902142421
immunologic response to influenza virus neuraminidase is influenced by prior experience with the associated viral hemagglutinin. iii. reduced generation of neuraminidase-specific helper t cells in hemagglutinin-primed balb/c mice primed by influenza virus infection to h3 hemagglutinin and n2 neuraminidase, presentation of n2 in association with a heterosubtypic (h7) hemagglutinin results in production of a greater amount of n2 antibody than is found with homologous (h3n2) reimmunization. titration of primed helper t cell (th) activity by adoptive transfer of purified t cells to athymic mice given h6n2 vaccine demonstrates a lesser number of n2-specific th cells in mice subjected to homologous reimmunizatio ...19872957444
antigen-presenting b cells and helper t cells cooperatively mediate intravirionic antigenic competition between influenza a virus surface glycoproteins.parenteral vaccination of balb/c mice primed by infection with h3n2 variants of influenza a virus results in a reduced production of n2 antibody in response to homologous (h3n2) vaccine compared with the response to an h7n2 vaccine equal in n2 immunologenicity. we now have studied the interaction in vitro of purified splenic b and t lymphocytes from variably immunized mice to ascertain the cellular basis of the hemagglutinin (ha)-influenced antibody response to neuraminidase (na). assay of the p ...19872958849
comparison of hemagglutination-inhibition, agar gel precipitin, and enzyme-linked immunosorbent assay for measuring antibodies against influenza viruses in chickens.individual variations in serological response to avian influenza virus infection were demonstrated after experimental infection of specific-pathogen-free chickens with h6n2 influenza virus. homologous antibodies were detected from the 6th to the 157th day after infection using hemagglutination-inhibition or enzyme-linked immunosorbent assay and from the 11th to the 157th day by agar gel precipitation test.19872960313
characterization of virulent and avirulent a/chicken/pennsylvania/83 influenza a viruses: potential role of defective interfering rnas in april 1983, an influenza virus of low virulence appeared in chickens in pennsylvania. subsequently, in october 1983, the virus became virulent and caused high mortality in poultry. the causative agent has been identified as an influenza virus of the h5n2 serotype. the hemagglutinin is antigenically closely related to tern/south africa/61 (h5n3) and the neuraminidase is similar to that from human h2n2 strains (e.g., a/japan/305/57) and from some avian influenza virus strains (e.g., a/turkey/ma ...19853973976
isolation of immunogenic neuraminidases of human influenza viruses by a combination of genetic and biochemical procedures.neuraminidases were purified from reassortant viruses (h6n1 and h6n2) containing the two antigenic subtypes (n1 and n2) found in human influenza viruses. surface glycoproteins were solubilized with octylglucoside, and the neuraminidase was isolated by chromatography on deae-sephadex. neuraminidase isolated by this technique coeluted with viral lipids and spontaneously formed liposomes on dialysis. the purified neuraminidase was immunogenic in rabbits, producing a significant antibody response at ...19846205018
isolation of ortho- and paramyxoviruses from wild birds in western australia, and the characterization of novel influenza a part of the world health organization's international programme on the ecology of influenza, cloacal swabs were collected from 3,736 birds belonging to 67 species over a 3-year period in western australia for the isolation of ortho- and paramyxoviruses. a total of 24 influenza a viruses were isolated from various species of ducks, shearwaters , noddies , terns and a coot , and were subtyped as h1n9 , h3n8 , h4n4 , h4n6 , h6n2 , h6n4 , h?n2, h?n6 and h? n9 . the h? haemagglutinins did not reac ...19846430260
isolation of influenza a viruses from birds in great britain during 1980 and 1981.during 1980 and 1981 influenza a viruses of subtypes h3n2, h3n8, h4n1, h4n6, h6n2, h6n8, h7n7, h11n8 and h11n9 were isolated from birds in great britain, usually as a result of investigations of disease or death. however, all viruses were shown to be of low virulence for chickens in pathogenicity index tests. there was one occurrence of influenza virus infection of turkeys (h6n8) but viruses were frequently obtained from domestic ducks. other viruses were isolated from exotic birds in zoos or bi ...19826815876
multiple avian influenza infection: selection of a non-avid virus by a heterologous avian host.experimental infection of domestic fowl, ducks and geese with an influenza a virus (h7n2) isolated from a domestic duck showed that this virus was apathogenic for these poultry. a second virus (h6n2), also apathogenic and more 'non-avid' than any such isolates previously recognised in surveillance of domestic poultry in hong kong, was isolated from one goose after h7n2 shedding had ceased. this goose, in effect, acted as a selective isolation system for the h6n2 virus whose presence in the field ...19827134641
observations on the relationship in chickens between the virulence of some avian influenza viruses and their pathogenicity for various organs.comparative histological and immunocytochemical studies were conducted on formalin-fixed tissues from chickens infected with avian influenza viruses of varying virulence. results showed a distinct pattern of disease that depended on the virulence of the virus and the susceptibility of the birds. at 3 days post-intranasal inoculation with a highly virulent h7n7 virus, all 6-to-8-week-old specific-pathogen-free (spf) birds were affected, and all developed pancreatic necrosis and encephalitis assoc ...19958561728
reassortment and interspecies transmission of north american h6n2 influenza viruses.h6n2 influenza viruses were isolated from california chickens in 2000 and 2001. here we report the characterization of these h6n2 viruses, one of the few descriptions of non-h5, non-h7 subtype influenza viruses in this host. the h6n2 viruses were nonpathogenic in experimentally infected chickens and could be divided into three genotypes. all three genotypes of virus had similar surface glycoproteins and all contained an 18 amino acid deletion in the neuraminidase, a characteristic of other chick ...200212033764
avian influenza in the western hemisphere including the pacific islands and australia.between 1997 and 2001, there was one report of highly pathogenic avian influenza (hpai) in the western hemisphere and pacific basin. in 1997, in new south wales, australia, an outbreak caused by avian influenza (ai) virus subtype h7n4 involved both chickens and emus. all other reports of infections in poultry and isolations from wild bird species in the region pertained to low pathogenicity (lp) ai virus. animal health officials in canada reported isolations of subtypes h1, h6, h7, and h10 from ...200314575067
the quest of influenza a viruses for new hosts.there is increasing evidence that stable lineages of influenza viruses are being established in chickens. h9n2 viruses are established in chickens in eurasia, and there are increasing reports of h3n2, h6n1, and h6n2 influenza viruses in chickens both in asia and north america. surveillance in a live poultry market in nanchang, south central china, reveals that influenza viruses were isolated form 1% of fecal samples taken from healthy poultry over the course of 16 months. the highest isolation r ...200314575076
low-pathogenicity avian influenza virus (h6n2) in chickens in california, 2000-02.during 2000, 2001, and january 2002, avian influenza virus was isolated from chickens from 12 different locations in california. all the isolates were typed as h6n2 and determined to be of low pathogenicity for chickens. nine of the isolates came from commercial layer flocks; one from a backyard flock; one from a mixed age flock, where ducks and squabs were also present; and one from a primary broiler breeder. although a drop in egg production and increased mortality were among the disease signs ...200314575080
multiple genotypes of nonpathogenic h6n2 influenza viruses isolated from chickens in california.from february 2000 through september 2001, a limited number of h6n2 influenza viruses were isolated from chickens in california. this report describes the genetic characterization of nine of these h6n2 viruses. all of the viruses analyzed had phylogenetically similar hemagglutinin (ha) and neuraminidase molecules that suggested the viruses shared a recent common ancestor. the analysis of the ha sequence of these viruses with all available h6 viruses from different hosts and locations showed that ...200314575084
the occurrence of avian influenza a subtype h6n2 in commercial layer flocks in southern california (2000-02): clinicopathologic findings.between february 2000 and february 2002, the california animal health and food safety laboratory system diagnosed 26 cases of low-pathogenic h6n2 avian influenza from 12 commercial egg-laying farms. the most common gross and histologic lesions observed in infected chickens were fibrinous yolk peritonitis, salpingitis, oophoritis, and nephritis. edema of the mesentery of the oviduct and pale, swollen kidneys were also observed. mortality in infected flocks ranged from 0.25% to 3%, and egg product ...200314575145
multiple gene segment reassortment between eurasian and american lineages of influenza a virus (h6n2) in guillemot (uria aalge).guillemots banded in the northern baltic sea were screened for influenza a virus (iav). three out of 26 sampled birds tested positive by rt-pcr. two of these were characterized as subtype h6n2. phylogenetic analyses showed that five gene segments belonged to the american avian lineage of iavs, whereas three gene segments belonged to the eurasian lineage. our findings indicate that avian iavs may have a taxonomically wider reservoir spectrum than previously known and we present the first report o ...200515883657
comparison of the anti-influenza virus activity of cyclopentane derivatives with oseltamivir and zanamivir in vivo.cyclopentane derivatives, designated as bcx-1812, bcx-1827, bcx-1898, and bcx-1923, were tested in parallel with oseltamivir carboxylate and zanamivir for the in vivo activity in mice infected with a/turkey/mas/76 x a/beijing/32/92 (h6n2) influenza virus. the compounds were tested orally and intranasally at different dose levels. bcx-1812, bcx-1827, and bcx-1923 showed more than 50% protection at 1mg/kg/day dose level on oral treatment. the intranasal treatment was 100% effective even at 0.01 mg ...200515911320
[phylogenetic analysis of the surface glycoprotein genes of an aquatic bird origin influenza virus isolate a/duck/yangzhou/233/2002 (h6n2)].several h6 subtype avian a influenza viruses were isolated from aquatic birds in some live bird markets when we surveyed the ecology of the influenza in east china for more than two years and identified by specific rt-pcr. in this paper, the hemagglutinin (ha) and neuraminidase (na) gene of one representative virus named a/duck/yangzhou/233/ 2002 (h6n2) (dk/yz/233/02) had been sequenced. phylogenetic analysis of the h6 gene sequences available in the influenza sequence database showed that the d ...200516245856
commercial immunoassay kits for the detection of influenza virus type a: evaluation of their use with poultry.five antigen capture immunoassay test kits, directigen flu a (becton dickinson), quickvue influenza test kit (quidel), flu oia (thermobiostar), zstat flu (zymetx, inc.) and now flu a test (binax) were used to detect avian influenza virus (aiv) in clinical specimens as per manufacturers' protocols. each kit was shown to be specific for aiv propagated in embryonating chicken eggs (ece); other respiratory viruses of poultry tested gave negative results. the directigen flu a kit proved to be 10-fold ...200516404986
protection against h1, h5, h6 and h9 influenza a infection with liposomal matrix 2 epitope vaccines.the recent emergence of multiple avian influenza a subtypes that cause human disease (i.e., h5n1, h9n2 and h7n7), coupled with the fear that one of these strains might precipitate a new pandemic, underscores the need to develop new technological approaches to immunization which elicit protective immune responses against multiple subtypes of influenza a. in response to this demand, several matrix 2 protein ectodomain segments (m2ea) corresponding to the h1n1, h5n1 and h9n2 influenza strains were ...200616713037
molecular epizootiology of recurrent low pathogenic avian influenza by h9n2 subtype virus in korea.the first outbreak of low pathogenic avian influenza (lpai), h9n2 virus subtype, in 1996 prompted an eradication response, but lpai returned to korea in 1999. the relationship between the first and the recurrent viruses is unclear. to determine the molecular epizootiology of recurrent lpai, we performed phylogenetic analysis with partial nucleotide sequences of four gene segments (ha, na, np and pb2) from eight chicken-origin h9n2 viruses. the recurrent h9n2 viruses showed higher nucleotide simi ...200616854644
outbreaks of avian influenza h6n2 viruses in chickens arose by a reassortment of h6n8 and h9n2 ostrich viruses.the first recorded outbreak of avian influenza (ai) in south african chickens (low pathogenicity h6n2) occurred at camperdown, kwazulu/natal province (kzn) in june 2002. to determine the source of the outbreak, we defined the phylogenetic relationships between various h6n2 isolates, and the previously unpublished gene sequences of an h6n8 virus isolated in 1998 from ostriches in the leeu gamka region (a/ostrich/south africa/kk98/98). we demonstrated that two distinct genetic h6n2 lineages (sub-l ...200716927114
detection of antibodies in serum and egg yolk following infection of chickens with an h6n2 avian influenza serologic surveillance programs to detect avian influenza viruses (aivs) in table egg-laying chickens have been initiated by several states as a response to the economic threat posed by these viruses. most outbreaks of avian influenza in domestic poultry are caused by mildly pathogenic aivs. in the study reported here, infection by an h6n2 aiv was used as a model of mildly pathogenic aiv infections in egg-type chickens. the total number of eggs laid by 5 control hens was 619 or 0.904 eggs ...200617037610
persistence of immunity in commercial egg-laying hens following vaccination with a killed h6n2 avian influenza vaccine.the california poultry industry experienced an outbreak of h6n2 avian influenza beginning in february 2000. the initial infections were detected in three commercial egg-laying flocks and a single noncommercial backyard flock but later spread to new premises. the vaccination of pullet flocks with a commercially prepared, killed autogenous vaccine prior to their placements on farms with infected or previously infected flocks was used as a part of the eradication programs for some multiage, commerc ...200617039836
genome characterisation of the newly discovered avian influenza a h5n7 virus subtype denmark, in 2003, a previously unknown subtype combination of avian influenza a virus, h5n7 (a/mallard/denmark/64650/03), was isolated from a flock of 12,000 mallards. the h5n7 subtype combination might be a reassortant between recent european avian influenza a h5, h7, and a third subtype, possibly an h6. the haemagglutinin and the acidic polymerase genes of the virus were closely related to a low-pathogenic danish h5n2 virus a/duck/denmark/65041/04 (h5n2). the neuraminidase gene and the non- ...200717115305
hampered foraging and migratory performance in swans infected with low-pathogenic avian influenza a is increasingly acknowledged that migratory birds, notably waterfowl, play a critical role in the maintenance and spread of influenza a viruses. in order to elucidate the epidemiology of influenza a viruses in their natural hosts, a better understanding of the pathological effects in these hosts is required. here we report on the feeding and migratory performance of wild migratory bewick's swans (cygnus columbianus bewickii yarrell) naturally infected with low-pathogenic avian influenza (lpai ...200717264886
phylogenetic analysis of low-pathogenicity avian influenza h6n2 viruses from chicken outbreaks (2001-2005) suggest that they are reassortants of historic ostrich low-pathogenicity avian influenza h9n2 and h6n8 viruses.low-pathogenicity (lpai) and high-pathogenicity (hpai) avian influenza viruses are periodically isolated from south african ostriches, but during 2002 the first recorded outbreak of lpai (h6n2) in south african chickens occurred on commercial farms in the camperdown area of kwazulu/natal (kzn) province. sequence analysis of all eight genes were performed and phylogenetic analysis was done based on the hemagglutinin and neuraminidasc sequences. results from phylogenetic analyses indicated that th ...200717494567
virologic findings in selected free-range mule duck farms at high risk for avian influenza infection.prevalence of avian influenza infection in free-range mule ducks (a cross between muscovy [cairina moschata domesticus] and pekin ducks [anas platyrhychos domesticus]) is a matter of concern and deserves particular attention. thus, cloacal swabs were collected blindly from 30 targeted mule flocks at 4, 8, and 12 wk of age between october 2004 and january 2005. they were stored until selection. on the basis of a positive h5 antibody detection at 12 wk of age with the use of four h5 antigens, the ...200717494595
avian influenza virus screening in wild waterfowl in norway, 2005.the prevalence of influenza a virus infection, and the distribution of different subtypes of the virus, were studied in 604 geese and ducks shot during ordinary hunting 2005. the study was based upon molecular screening of cloacal swabs taken by the hunters. the sampling included the following species: greylag (anser anser), mallard (anas platyrhynchos), wigeon (anas penelope), teal (anas crecca), goosander (mergus merganser), tufted duck (aythya fuligula), common scoter (melanitta nigra), golde ...200717494599
use of tetanus toxoid as a differentiating infected from vaccinated animals (diva) strategy for sero-surveillance of avian influenza virus vaccination in poultry.strategies for differentiating infected from vaccinated animals (diva) require improvement for increased surveillance of avian influenza (ai), where vaccination is employed to control disease. we propose a novel diva approach for chickens using tetanus toxoid (tt) as an exogenous marker independent of serotype and relatedness of circulating and vaccine strains. of 1779 chickens tested from australia, hong kong and china, 100% were seronegative for tt-specific antibodies without vaccination. teta ...200717583393
establishment of influenza a virus (h6n1) in minor poultry species in southern h6n1 virus, a/teal/hong kong/w312/97 (w312), was isolated during the "bird flu" incident in hong kong in 1997. genetic analysis suggested that this virus might be the progenitor of the a/hong kong/156/97 (hk/97) h5n1 virus, as seven of eight gene segments of those viruses had a common source. continuing surveillance in hong kong showed that a w312-like virus was prevalent in quail and pheasants in 1999; however, the further development of h6n1 viruses has not been investigated since 2001. her ...200717652385
genesis of pandemic influenza.during the last decade the number of reported outbreaks caused by highly pathogenic avian influenza (hpai) in domestic poultry has drastically increased. at the same time, low pathogenic avian influenza (lpai) strains, such as h9n2 in many parts of the middle east and asia and h6n2 in live bird markets in california, have become endemic. each ai outbreak brings the concomitant possibility of poultry-to-human transmission. indeed, human illness and death have resulted from such occasional transmi ...200717675883
[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
modulation of the immune responses in chickens by low-pathogenicity avian influenza virus h9n2.most low-pathogenicity avian influenza (lpai) viruses cause no or mild disease in avian species. little is known about the mechanisms of host defence and the immune responses of avian influenza-infected birds. this study showed that chicken macrophages are susceptible to infection with lpai h9n2 and h6n2 viruses and that infection led to apoptosis. in h9n2 virus-infected chicken macrophages, toll-like receptor 7 responded to infection and mediated the cytokine responses. whilst pro-inflammatory ...200818420808
avian influenza surveillance in hunter-harvested waterfowl from the gulf coast of texas (november 2005-january 2006).the objectives of our study were to determine prevalence of avian influenza viruses (aiv) on wintering grounds on the texas gulf coast, usa, and to compare real-time reverse-transcriptase polymerase chain reaction (rrt-pcr) and virus isolation for detection of aiv in cloacal swabs from wild waterfowl. cloacal swabs were collected from hunter-harvested waterfowl from november 2005 to january 2006 at four wildlife management areas. seven aiv were isolated from four species of ducks: green-winged t ...200818436675
surveillance of avian influenza viruses in northern pintails (anas acuta) in tohoku district, japan.among winter migratory waterfowl, northern pintails (anas acuta), in one of the largest flocks in tohoku district, northeast japan, were surveyed for influenza a viruses at five wintering sites in three prefectures, viz., aomori, akita, and miyagi. a total of 38 influenza a viruses were isolated from 2066 fecal samples collected during november 2006 through march 2007. the overall isolation rate was 1.84%. eleven different subtypes were isolated, including nine h5n2, seven h6n8, seven h10n1, fou ...200818459295
evaluation of a positive marker of avian influenza vaccination in ducks for use in h5n1 surveillance.control measures for h5n1 avian influenza involve increased biosecurity, monitoring, surveillance and vaccination. subclinical infection in farmed ducks is important for virus persistence. in major duck rearing countries, homologous h5n1 vaccines are being used in ducks, so sero-surveillance using h5- or n1-specific antibody testing cannot identify infected flocks. an alternative is to include a positive marker for vaccination. testing for an antibody response to the marker would confirm approve ...200818723069
transmission of low-pathogenicity avian influenza virus of subtype h6n2 from chickens to pekin ducks and japanese quail (coturnix coturnix japonica).in this experiment we evaluated the transmission characteristics of a chicken-adapted low-pathogenicity avian influenza virus (lpaiv) of subtype h6n2, from infected chickens to japanese quail and pekin ducks, which are commonly sold in live bird markets located in southern california. the layout of the cages and bird-handling practices were similar to those found in southern california live bird markets. five out of 20 chickens were inoculated with lpaiv h6n2, and placed in direct contact with f ...200919156581
[distribution of avian influenza virus subtypes among domestic ducks in eastern china].to identify the distribution of avian influenza virus subtypes among domestic ducks in eastern china.200819160806
[monitoring influenza a virus and newcastle disease virus in migratory waterfowls in sanjiang natural reserve of heilongjiang province].in order to monitor the present situation of avian influenza virus (aiv) and newcastle disease virus (ndv) in migratory waterfowls effectively, 158 tracheal and cloacal swab samples for wild birds were collected from sanjiang natural reserve during migratory seasons in october 2005, april 2006 and october 2006.200819160826
[the study of the nonpathogenic influenza virus a/gull/moscow/3100/2006 (h6n2) isolated in moscow].the influenza virus a/gull/moscow/3100/2006 (h6n2) was isolated from gull feces within the precincts of moscow in autumn 2006. the nucleotide sequence of the complete genome (genbank, eu152234-eu152241) and genotype (k, g, d, 6b, f, 2d, f, 1e) for this virus were determined. phylogenetic analysis suggests that the h6n2 virus derived by numerous reassortment between viruses that have been circulating among different birds in europe since 1999 and in south-east asia (na gene) for last years. migra ...200919280991
survival of avian influenza and newcastle disease viruses in compost and at ambient temperatures based on virus isolation and real-time reverse transcriptase four composting experiments, survival of avian influenza (ai) and newcastle disease (nd) viruses was assessed by virus isolation in embryonated chicken eggs (eces) and by real-time reverse transcriptase-polymerase chain reaction. specimens contained in nylon mesh bags consisted of 20-g samples of chicken manure, used litter, or feed that had been inoculated with allantoic fluid containing an ai virus (h6n2, expt. 1) or an nd vaccine virus (expt. 2). other specimens consisted of 20-g samples o ...200919432000
survival of the avian influenza virus (h6n2) after land integral component in preventing an avian influenza pandemic is containment and disposal of infected bird (poultry) carcasses. disposal of carcasses in subtitle d municipal solid waste (msw) landfills may be an advantageous option due to their large capacities and facility distribution in the u.s. in this study, the survival of h6n2 avian influenza virus (aiv) was measured in a methanogenic landfill leachate and water as a function of temperature, conductivity, and ph. elevated temperature an ...200919569331
an evaluation of transmission routes for low pathogenicity avian influenza virus among chickens sold in live bird markets.many theories about the modes of avian influenza virus (aiv) transmission have been proposed, but few have been quantified, and none within a flock or live bird market (lbm) setting where birds are often kept in stacked cages. we describe a novel experimental design and the results collected for the purpose of estimating transmission rates specific to the potential modes of aiv transmission within an lbm. chickens of the strains and ages found in california lbms were inoculated with low pathogen ...200919747706
a flock-tailored early warning system for low pathogenic avian influenza (lpai) in commercial egg laying flocks.the aim of this study was to develop and evaluate an early warning system (ews) for commercial egg laying flocks to detect the subtle mortality and egg production changes that characterize low pathogenic avian influenza virus (lpaiv) infections. an ews will create an alert when the recommended 'trigger point' is reached or exceeded. previously used ewss are based on fixed alert levels, while the proposed ews customizes the alert level to each flock. while a fixed approach may be valid for highly ...200919767114
genetic relatedness of h6 subtype avian influenza viruses isolated from wild birds and domestic ducks in korea and their pathogenicity in animals.we report the genetic characterization of h6 avian influenza (ai) viruses isolated from domestic ducks and wild birds in korea between april 2008 and april 2009. a phylogenetic analysis showed that the h6n1 viruses of wild birds and domestic ducks were of the same genotype (k-1) and were similar to the h6n1 virus isolated from a live poultry market in 2003, as six of the eight gene segments of those viruses had a common source. however, the h6n2 viruses of domestic poultry were separated into fo ...201019812266
biological and genetic characterization of a low-pathogenicity avian influenza h6n2 virus originating from a healthy eurasian coot.influenza a virus, a/eurasian coot/western australia/2727/79 (h6n2), from an apparently healthy coot was characterized. this virus was able to grow on mdck cells and produce a cytopathic effect in the absence of exogenous trypsin and was further characterized as a low-pathogenicity avian influenza virus, with an intravenous pathogenicity index of 0.15 and a (321)pqaetrg(328) motif at the cleavage site of the haemagglutinin gene. it infected domestic chickens, resulting in seroconversion and inte ...201020112121
field detection of avian influenza virus in wild birds: evaluation of a portable rrt-pcr system and freeze-dried reagents.wild birds have been implicated in the spread of highly pathogenic avian influenza (hpaiv) of the h5n1 subtype, prompting surveillance along migratory flyways. sampling of wild birds is often conducted in remote regions, but results are often delayed because of limited local analytical capabilities, difficulties with sample transportation and permitting, or problems keeping samples cold in the field. in response to these challenges, the performance of a portable real-time, reverse transcriptase- ...201020206650
biologic characterization of chicken-derived h6n2 low pathogenic avian influenza viruses in chickens and ducks.low pathogenic avian influenza h6n2 viruses were biologically characterized by infecting chickens and ducks in order to compare adaptation of these viruses in these species. we examined the clinical signs, virus shedding, and immune response to infection in 4-wk-old white leghorn chickens and in 2-wk-old pekin ducks. five h6n2 viruses isolated between 2000 and 2004 from chickens in california, and one h6n2 virus isolated from chickens in new york in 1998, were given intrachoanally at a dose of 1 ...201020408410
establishment of an h6n2 influenza virus lineage in domestic ducks in southern china.multiple reassortment events between different subtypes of endemic avian influenza viruses have increased the genomic diversity of influenza viruses circulating in poultry in southern china. gene exchange from the natural gene pool to poultry has contributed to this increase in genetic diversity. however, the role of domestic ducks as an interface between the natural gene pool and terrestrial poultry in the influenza virus ecosystem has not been fully characterized. here we phylogenetically and ...201020463062
potential of low pathogenicity avian influenza viruses of wild bird origin to establish experimental infections in turkeys and chickens.the potential of low pathogenicity (lp) avian influenza virus (aiv) isolates of wild bird origin to establish infection in commercial turkeys and broiler chickens was studied. isolates, representing subtypes h5n1, h7n3, h6n2, and h3n6, were recovered in 2005 and 2006 from waterfowl and shorebirds in the delmarva peninsula region of the east coast of the united states. the lp aiv isolates were not pathogenic for 2-wk-old meat-type turkeys and broiler chickens. no mortality, clinical signs, or gro ...201020945794
[characterizations of avian influenza virus h6n6 subtype isolated from domestic muscovy duck].to enrich the epidemiologic data of the waterfowl origin avian influenza virus (aiv).201021090254
strategies for improving the efficacy of a h6 subtype avian influenza dna vaccine in chickens.a low-pathogenicity avian influenza h6n2 virus was used to investigate approaches to improve dna vaccine efficacy. the viral hemagglutinin (ha) gene or its chicken biased ha gene, incorporating a kozak sequence, was cloned into a pcaggs vector to produce the pcag-hak and pcag-optihak constructs. following two intramuscular injections, the seroconversion rate in vaccinated chickens with 10, 100 or 300 µg pcag-hak were 87.5%, 75% and 75%, respectively. the profile of h6 hemagglutination inhibition ...201121333689
characterization of influenza a viruses isolated from wild waterfowl in zambia.although the quest to clarify the role of wild birds in the spread of the highly pathogenic h5n1 avian influenza virus (aiv) has yielded considerable data on aivs in wild birds worldwide, information regarding the ecology and epidemiology of aivs in african wild birds is still very limited. during aiv surveillance in zambia (2008-2009), 12 viruses of distinct subtypes (h3n8, h4n6, h6n2, h9n1 and h11n9) were isolated from wild waterfowl. phylogenetic analyses demonstrated that all the isolates we ...201121367986
the use of fta® filter papers for diagnosis of avian influenza virus.avian influenza viruses (aivs) infect a wide range of host species including domestic poultry and wild birds; also, aivs may infect humans in whom some highly pathogenic viruses (hpaiv) may cause acute fatal disease. accurate laboratory diagnosis of aiv infections requires time-consuming and logistically complex precautionary measures for shipment of specimens or viruses to avoid biohazard exposure. the feasibility was investigated of the flinders technology associates filter paper (fta® card) f ...201121419801
a novel chicken lung epithelial cell line: characterization and response to low pathogenicity avian influenza virus.avian influenza virus (aiv) infections of the chicken occur via the respiratory route. unlike ducks which are considered as a natural aiv reservoir, chickens are highly susceptible to aiv infections and do not possess the rig-i pattern recognition receptor involved in triggering the antiviral interferon response. to study the chicken innate immune response to aiv in the respiratory tract, we established an epithelial cell line (clec213) from lung explants of white leghorn chickens. clec213 cells ...201121557972
prevalence of low pathogenicity avian influenza virus during 2005 in two u.s. live bird market systems.oropharyngeal and cloacal swabs were collected from poultry sold in two live bird market (lbm) systems to estimate the prevalence of low pathogenicity avian influenza virus (lpaiv) shedding during the summer and fall of 2005. random sampling was conducted in three lbms in minnesota where 50 birds were sampled twice weekly for 4 wk, and in three lbms in a california marketing system. a stratified systematic sampling method was used to collect samples from southern california lbms, where lpaiv was ...201121793439
molecular evolution of the h6 subtype influenza a viruses from poultry in eastern china from 2002 to 2010.although extensive data demonstrates that the majority of h6 duck isolates belonged to a single h6n2 virus lineage with a single gene constellation in southern china from 2000 to 2005, the prevalence of h6n2 virus in poultry in eastern china is largely unknown.201121999472
ultrasonic synthetic technique to manufacture a phema nanopolymeric-based vaccine against the h6n2 avian influenza virus: a preliminary investigation.this preliminary study investigated the use of poly (2-hydroxyethyl methacrylate) (phema) nanoparticles for the delivery of the deoxyribonucleic acid (dna) vaccine pcag-hak, which expresses the full length hemagglutinin (ha) gene of the avian influenza a/eurasian coot/western australian/2727/1979 (h6n2) virus with a kozak sequence which is in the form of a pcaggs vector. the loaded and unloaded nanoparticles were characterized using field-emission scanning electron microscopy. further characteri ...201122114480
in vitro inhibition of influenza virus infection by a crude extract from isatis indigotica root resulting in the prevention of viral attachment.isatis indigotica root (iir) has been widely used as a chinese medicinal herb to treat regular seasonal influenza over the long history of traditional chinese medicinal practice. however, its inhibitory activities against influenza virus infections along with the associated mechanisms have not been investigated comprehensively. in this study, the chemical nature, mode of action and in vitro anti-influenza activities of a crude extract ( ...201122179315
comparative safety, immunogenicity, and efficacy of several anti-h5n1 influenza experimental vaccines in a mouse and chicken models (testing of killed and live h5 vaccine).please cite this paper as: gambaryan et al. (2011) comparative safety, immunogenicity, and efficacy of several anti-h5n1 influenza experimental vaccines in a mouse and chicken models. parallel testing of killed and live h5 vaccine. influenza and other respiratory viruses doi: 10.1111/j.1750-2659.2011.00291.x. objective  parallel testing of inactivated (split and whole virion) and live vaccine was conducted to compare the immunogenicity and protective efficacy against homologous and heterosubtypi ...201121951678
[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
characterization of a low pathogenic avian influenza virus (h6n1) isolated from avian influenza virus (aiv), a/turkey/israel/09 subtype h6n1, was isolated from turkey poults exhibiting typical pathology associated with aiv infection. the virus was characterized by rt-pcr using aiv subtype-specific primers and by the haemagglutination inhibition test using aiv subtype-specific antisera. the virus has an intravenous pathogenicity index of 0 and possessed a nucleotide sequence at the cleavage site of the hemagglutinin gene, pqietr*glf, associated with avian influenza viruse ...201123074655
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
duck interferon-inducible transmembrane protein 3 mediates restriction of influenza viruses.interferon-inducible transmembrane proteins (ifitms) can restrict the entry of a wide range of viruses. ifitm3 localizes to endosomes and can potently restrict the replication of influenza a viruses (iav) and several other viruses that also enter host cells through the endocytic pathway. here, we investigate whether ifitms are involved in protection in ducks, the natural host of influenza virus. we identify and sequence duck ifitm1, ifitm2, ifitm3, and ifitm5. using quantitative pcr (qpcr), we d ...201526468537
antiviral activity of isatis indigotica root-derived clemastanin b against human and avian influenza a and b viruses in vitro.clemastanin b, 7s,8r,8'r-(-)-lariciresinol-4,4'-bis-o-β-d-glucopyranoside, is one of the major lignans extracted from isatis indigotica root (iir). in this study, the anti-influenza activities of clemastanin b were evaluated in vitro. clemastanin b was found to inhibit different subtypes of human (h1n1, including swine-origin h1n1; h3n2 and influenza b) and avian influenza viruses (h6n2, h7n3, h9n2) at different magnitudes of activity (ic50 0.087-0.72 mg/ml) while this compound was inactive agai ...201323403777
rapid detection of equine influenza virus h3n8 subtype by insulated isothermal rt-pcr (iirt-pcr) assay using the pockit™ nucleic acid analyzer.equine influenza (ei) is an acute, highly contagious viral respiratory disease of equids. currently, equine influenza virus (eiv) subtype h3n8 continues to be the most important respiratory pathogen of horses in many countries around the world. the need to achieve a rapid diagnosis and to implement effective quarantine and movement restrictions is critical in controlling the spread of eiv. in this study, a novel, inexpensive and user-friendly assay based on an insulated isothermal rt-pcr (iirt-p ...201424992669
[genomic characteristics of 2 strains of influenza a(h9n2)virus isolated from human infection cases in anhui province].to understand genomic characteristics of 2 strains of influenza a(h9n2)virus isolated from human infection cases in anhui province in 2015.201627188368
evolutionary dynamics and global diversity of influenza a virus.the increasing number of zoonotic infections caused by influenza a virus (iav) subtypes of avian origin (e.g., h5n1 and h7n9) in recent years underscores the need to better understand the factors driving iav evolution and diversity. to evaluate the current feasibility of global analyses to contribute to this aim, we evaluated information in the public domain to explore iav evolutionary dynamics, including nucleotide substitution rates and selection pressures, using 14 iav subtypes in 32 differen ...201526311890
complete genome sequence of a novel reassortant avian influenza h1n2 virus isolated from a domestic sparrow in 2012.we report here the complete genome sequence of a novel h1n2 avian influenza virus strain, a/sparrow /guangxi/gxs-1/2012 (h1n2), isolated from a sparrow in the guangxi province of southern china in 2012. all of the 8 gene segments (hemagglutinin [ha], nucleoprotein [np], matrix [m], polymerase basic 2 [pb2], neuraminidase [na], polymerase acidic [pa], polymerase basic 1 [pb1], and nonstructural [ns] genes) of this natural recombinant virus are attributed to the eurasian lineage, and phylogenetic ...201323868121
local-scale diversity and between-year "frozen evolution" of avian influenza a viruses in nature.influenza a virus (iav) in wild bird reservoir hosts is characterized by the perpetuation in a plethora of subtype and genotype constellations. multiyear monitoring studies carried out during the last two decades worldwide have provided a large body of knowledge regarding the ecology of iav in wild birds. nevertheless, other issues of avian iav evolution have not been fully elucidated, such as the complexity and dynamics of genetic interactions between the co-circulating iav genomes taking place ...201425075739
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
the zoonotic potential of avian influenza viruses isolated from wild waterfowl in zambia.whilst remarkable progress in elucidating the mechanisms governing interspecies transmission and pathogenicity of highly pathogenic avian influenza viruses (aivs) has been made, similar studies focusing on low-pathogenic aivs isolated from the wild waterfowl reservoir are limited. we previously reported that two aiv strains (subtypes h6n2 and h3n8) isolated from wild waterfowl in zambia harbored some amino acid residues preferentially associated with human influenza virus proteins (so-called hum ...201424862188
long-term variation in influenza a virus prevalence and subtype diversity in migratory mallards in northern 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
radix isatidis polysaccharides inhibit influenza a virus and influenza a virus-induced inflammation via suppression of host tlr3 signaling in vitro.influenza remains one of the major epidemic diseases worldwide, and rapid virus replication and collateral lung tissue damage caused by excessive pro-inflammatory host immune cell responses lead to high mortality rates. thus, novel therapeutic agents that control influenza a virus (iav) propagation and attenuate excessive pro-inflammatory responses are needed. polysaccharide extract from radix isatidis, a traditional chinese herbal medicine, exerted potent anti-iav activity against human seasona ...201728085062
oseltamivir resistance in influenza a(h6n2) caused by an r292k substitution in neuraminidase is not maintained in mallards without drug pressure.wild waterfowl is the natural reservoir of influenza a virus (iav); hosted viruses are very variable and provide a source for genetic segments which can reassort with poultry or mammalian adapted iavs to generate novel species crossing viruses. additionally, wild waterfowl act as a reservoir for highly pathogenic iavs. exposure of wild birds to the antiviral drug oseltamivir may occur in the environment as its active metabolite can be released from sewage treatment plants to river water. resista ...201526422258
cellular scent of influenza virus infection.volatile organic compounds (vocs) emanating from humans have the potential to revolutionize non-invasive diagnostics. yet, little is known about how these compounds are generated by complex biological systems, and even less is known about how these compounds are reflective of a particular physiological state. in this proof-of-concept study, we examined vocs produced directly at the cellular level from b lymphoblastoid cells upon infection with three live influenza virus subtypes: h9n2 (avian), h ...201424719290
resistance mutation r292k is induced in influenza a(h6n2) virus by exposure of infected mallards to low levels of oseltamivir.resistance to neuraminidase inhibitors (nais) is problematic as these drugs constitute the major treatment option for severe influenza. extensive use of the nai oseltamivir (tamiflu®) results in up to 865 ng/l of its active metabolite oseltamivir carboxylate (oc) in river water. there one of the natural reservoirs of influenza a, dabbling ducks, can be exposed. we previously demonstrated that an influenza a(h1n1) virus in mallards (anas platyrhynchos) exposed to 1 µg/l of oc developed oseltamivi ...201323951116
low pathogenicity avian influenza viruses infect chicken layers by different routes of order to develop better control measures against avian influenza, it is necessary to understand how the virus transmits in poultry. in a previous study in which the infectivity and transmissibility of the pandemic h1n1 influenza virus was examined in different poultry species, we found that no or minimal infection occurred in chicken and turkeys intranasally (in) inoculated with the virus. however, we demonstrated that the virus can infect laying turkey hens by the intracloacal (ic) and intra ...201222856182
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
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
immunization with live nonpathogenic h5n3 duck influenza virus protects chickens against highly pathogenic h5n1 virus.development of an effective, broadly-active and safe vaccine for protection of poultry from h5n1 highly pathogenic avian influenza viruses (hpaivs) remains an important practical goal. in this study we used a low pathogenic wild aquatic bird virus isolate а/duck/moscow/4182/2010 (h5n3) (dk/4182) as a live candidate vaccine. we compared this virus with four live 1:7 reassortant anti-h5n1 candidate vaccine viruses with modified hemagglutinin from either a/vietnam/1203/04 (h5n1) or a/kurgan/3/05 (h ...201727640442
[testing of apathogenic influenza virus h5n3 as a poultry live vaccine].four h5n2 experimental vaccine strains and the apathogenic wild duck h5n3 influenza virus a/duck/ moscow/4182/2010 (dk/4182) were tested as a live poultry vaccine. experimental strains had the hemagglutinin of the a/vietnam/1203/04 strain lacking the polybasic ha cleavage site or the hemagglutinin from attenuated virus (ku/ at) that was derived from the highly pathogenic influenza virus a/chicken/kurgan/3/2005 (h5n1). the hemagglutinin of the ku-at has the amino acid substitutions asp54/asn and ...201526665435
epidemiological surveillance of low pathogenic avian influenza virus (lpaiv) from poultry in guangxi province, southern china.low pathogenic avian influenza virus (lpaiv) usually causes mild disease or asymptomatic infection in poultry. however, some lpaiv strains can be transmitted to humans and cause severe infection. genetic rearrangement and recombination of even low pathogenic influenza may generate a novel virus with increased virulence, posing a substantial risk to public health. southern china is regarded as the world "influenza epicenter", due to a rash of outbreaks of influenza in recent years. in this study, ...201324204754
complete genome sequence of an h3n2 avian influenza virus isolated from a live poultry market in eastern china.previous studies indicate that the h3 influenza virus has the ability to establish infection upon interspecies transmission and poses a threat to mammals. therefore, it is important to enhance the surveillance of h3 avian influenza viruses (aivs). in this study, a/duck/shanghai/c84/2009(h3n2) (c84) was isolated from a live poultry market in shanghai, china. using pcr and sequencing analyses, we obtained the whole-genome sequence of this virus. the h3n2 virus proved to be a novel multiple-gene re ...201223043175
tenacity of low-pathogenic avian influenza viruses in different types of poultry 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
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
an impedance immunosensor based on low-cost microelectrodes and specific monoclonal antibodies for rapid detection of avian influenza virus h5n1 in chicken swabs.early screening of suspected cases is the key to control the spread of avian influenza (ai) h5n1. in our previous studies, an impedance biosensor with an interdigitated array microelectrode based biochip was developed and validated with pure ai h5 virus, but had limitations in cost and reliability of the biochip, specificity of the antibody against asian in-field h5n1 virus and detection of h5n1 virus in real samples. the purpose of this study is to develop a low-cost impedance immunosensor for ...201525263315
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
complete genomic sequence of a novel natural recombinant h6n2 influenza virus from chickens in guangdong, southern, we reported the complete genome sequence of a novel h6n2 avian influenza virus (aiv) isolated from chicken in guangdong, southern china, in 2011 which was a natural recombinant virus between the h6n2 and h5n1 subtypes. it will help to understand the epidemiology and molecular characteristics of h6n2 influenza virus in southern china.201222733882
immunogenicity and protective efficacy of the norovirus p particle-m2e chimeric vaccine in chickens.the ectodomain of the influenza matrix protein 2 (m2e) is highly conserved across strains and has been shown to be a promising candidate for universal influenza vaccine in the mouse model. in this study, we tested immune response and protective efficacy of a chimeric norovirus p particle containing the avian m2e protein against challenges with three avian influenza (ai) viruses (h5n2, h6n2, h7n2) in chickens. two-week-old specific pathogen free chickens were vaccinated 3 times with an m2e-p part ...201526232342
persistence of highly pathogenic and low pathogenic avian influenza viruses in footbaths and poultry manure.a questionnaire was designed in order to gather information about bedding material and footbath preparation and maintenance in different productive units across the state of california.this information was used to plan two experiments. in the first experiment, we tested the effectiveness of footbaths in inactivating highly pathogenic (hp) and low pathogenic (lp) avian influenza viruses (aivs) on rubber boots. surprisingly, quaternary ammonia- and quaternary ammonia + glutaraldehyde-based footbat ...201728301246
molecular characterization of h6 subtype influenza viruses in southern china from 2009 to 2011.h6 avian influenza viruses (aivs), which are prevalent in domestic and wild birds in eurasian countries, have been isolated from pigs, a dog and a human. routine virological surveillance at live poultry markets or poultry farms was conducted in southern china from 2009 to 2011. this study investigated the genetic and antigenic characteristics, analyzed the receptor-binding properties and evaluated the kinetics of infectivity of the aivs in a549, mdck and pk15 cells. a total of 14 h6n6 and 2 h6n2 ...201627436363
an optimized enzyme-linked lectin assay to measure influenza a virus neuraminidase inhibition antibody titers in human sera.antibodies to neuraminidase (na), the second most abundant surface protein on influenza virus, contribute toward protection against influenza. the traditional thiobarbituric acid (tba) method to quantify na inhibiting antibodies is cumbersome and not suitable for routine serology. an enzyme-linked lectin assay (ella) described by lambre et al. (1990) is a practical alternative method for measuring na inhibition (ni) titers. this report describes optimization of the ella for measuring ni titers i ...201425233882
effect of the pb2 and m genes on the replication of h6 influenza virus in chickens.h6 subtype influenza viruses are commonly isolated from wild aquatic birds. however, limited information is available regarding h6 influenza virus isolated from chickens. we compared the viral genome segment between a/chicken/hong kong/w312/97 (h6n1), which was able to grow in chicken trachea, and a/duck/shantou/5540/01 (h6n2), which was isolated from wild aquatic duck, to explore the factors for effective replication in chicken. when chickens were inoculated with 7 + 1 reassortants (w312 backgr ...201424696782
evaluation of different chemical adjuvants on an avian influenza h6 dna vaccine in chickens.this study assessed the ability of three adjuvants (aluminium hydroxide, essai (microparticle) and phema (nanoparticle)) to enhance the immune response of chickens to an h6n2 avian influenza dna vaccine. no haemagglutination inhibition antibody was detected following two intramuscular immunizations with the adjuvanted and non-adjuvanted pcag-hak vaccine, which has previously been shown to induce moderate h6 haemagglutinin antibody response in spf chickens. following virus challenge, neither the ...201627314157
histopathologic characterization and shedding dynamics of guineafowl (numida meleagris) intravenously infected with a h6n2 low pathogenicity avian influenza virus.guineafowl of different ages were inoculated intravenously with a h6n2 wild waterfowl-origin low pathogenicity avian influenza virus (lpaiv). no clinical disease was observed. the infected birds had atrophy of the spleen, thymus, and cloacal bursa when compared with the noninfected control groups. the central and peripheral lymphoid tissues presented either lymphoproliferative or degenerative lesions that increased in intensity from 14 to 21 days postinoculation (dpi). lymphoid depletion was pre ...201627309068
inactivation of avian influenza viruses on porous and non-porous surfaces is enhanced by elevating absolute humidity.this study was to evaluate the effect of absolute humidity (ah), a combined factor of temperature and relative humidity (rh), on inactivation of avian influenza viruses (aivs) on surfaces. suspensions of the h9n2 or h6n2 aiv were deposited onto carrier surfaces that were either porous (pine wood) or non-porous (stainless steel, synthetic rubber and glass). the inoculated carriers were incubated at 23, 35 or 45°c with 25% or 55% rh for up to 28 days. after incubation, virus was recovered and quan ...201627059695
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