| serologic evidence of avian influenza virus infections among nigerian agricultural workers. | nigeria has had multiple incursions of highly pathogenic avian influenza a (hpai) h5n1 virus into its poultry population since 2006. this study aimed to determine if nigerians exposed to poultry had evidence of avian influenza virus transmission to man. between 2008 and 2010, 316 adult farmers and open market workers and 54 age-group matched, non-animal exposed controls were enrolled in a prospective, population-based study of zoonotic influenza transmission in four towns in southeastern nigeria ... | 2013 | 23400898 |
| receptor specificity and erythrocyte binding preferences of avian influenza viruses isolated from india. | hemagglutination (ha) and hemagglutination inhibition (hi) assays are conventionally used for detection and identification of influenza viruses. hi assay is also used for detection of antibodies against influenza viruses. primarily turkey or chicken erythrocytes [red blood cells (rbcs)] are used in these assays, as they are large, nucleated, and sediment fast, which makes it easy to determine the titer. human influenza viruses agglutinate rbcs from chicken, human, and guinea pig, but not from ho ... | 2012 | 23110802 |
| genome sequence of a novel reassortant h3n2 avian influenza virus from domestic mallard ducks in eastern china. | the h3 subtype avian influenza virus (aiv) can provide genes for human influenza virus through gene reassortment, which raises great concerns in terms of its potential threat to human health. here, we report the complete genome sequence of a novel h3n2 aiv isolated from domestic ducks in the jiangsu province of eastern china in 2004, which is a natural recombinant virus whose genes are derived from h3n8, h5n1, h5n2, h11n2, h4n6, and h1n1 aivs. this genome will help to understand the epidemiology ... | 2013 | 23580713 |
| complete genome sequence of a novel reassortant h11n2 avian influenza virus isolated from a live poultry market in eastern china. | a/chicken/nanjing/908/2009(h11n2) (ck908) was isolated from a live poultry market in nanjing, china. using pcr and sequencing analysis, we obtained the complete genome sequences of the ck908 virus. the sequence analysis demonstrated that this h11n2 virus was a novel reassortant aiv whose pb1, pb2, pa, ha, np, na, m, and ns genes originated from h9n2, h7n7, h5n2, h11n8, h3n6, h6n2, h1n1, and h5n1, respectively. knowledge regarding the complete genome sequences of the ck908 virus will be useful fo ... | 2012 | 23087108 |
| genetically diverse low pathogenicity avian influenza a virus subtypes co-circulate among poultry in bangladesh. | influenza virus surveillance, poultry outbreak investigations and genomic sequencing were assessed to understand the ecology and evolution of low pathogenicity avian influenza (lpai) a viruses in bangladesh from 2007 to 2013. we analyzed 506 avian specimens collected from poultry in live bird markets and backyard flocks to identify influenza a viruses. virus isolation-positive specimens (n = 50) were subtyped and their coding-complete genomes were sequenced. the most frequently identified subtyp ... | 2016 | 27010791 |
| long-term variation in influenza a virus prevalence and subtype diversity in migratory mallards in northern europe. | data on long-term circulation of pathogens in wildlife populations are seldom collected, and hence understanding of spatial-temporal variation in prevalence and genotypes is limited. here, we analysed a long-term surveillance series on influenza a virus (iav) in mallards collected at an important migratory stopover site from 2002 to 2010, and characterized seasonal dynamics in virus prevalence and subtype diversity. prevalence dynamics were influenced by year, but retained a common pattern for a ... | 2014 | 24573857 |
| reassortment of influenza a viruses in wild birds in alaska before h5 clade 2.3.4.4 outbreaks. | sampling of mallards in alaska during september 2014-april 2015 identified low pathogenic avian influenza a virus (subtypes h5n2 and h1n1) that shared ancestry with highly pathogenic reassortant h5n2 and h5n1 viruses. molecular dating indicated reassortment soon after interhemispheric movement of h5n8 clade 2.3.4.4, suggesting genetic exchange in alaska or surrounds before outbreaks. | 2017 | 28322698 |
| human monoclonal antibody 81.39a effectively neutralizes emerging influenza a viruses of group 1 and 2 hemagglutinins. | the pandemic threat posed by emerging zoonotic influenza a viruses necessitates development of antiviral agents effective against various antigenic subtypes. human monoclonal antibody (hmab) targeting the hemagglutinin (ha) stalk offers a promising approach to control influenza virus infections. here, we investigated the ability of the hmab 81.39a to inhibit in vitro replication of human and zoonotic viruses, representing 16 ha subtypes. the majority of viruses were effectively neutralized by 81 ... | 2016 | 27630240 |
| rapid detection of avian influenza virus h5n1 in chicken tracheal samples using an impedance aptasensor with gold nanoparticles for signal amplification. | highly pathogenic avian influenza virus h5n1 is a continuous threat to public health and poultry industry. the recurrence of the h5n1 led us to develop a robust, specific, and rapid detection method for the virus. in this study, an impedance aptasensor was developed for the virus detection using specific h5n1 aptamer and a gold interdigitated microelectrode. streptavidin was immobilized on the microelectrode surface and biotin labeled h5n1 aptamer was bound to the immobilized streptavidin. the m ... | 2016 | 27452670 |
| protective efficacy of an h5n1 inactivated vaccine against challenge with lethal h5n1, h5n2, h5n6, and h5n8 influenza viruses in chickens. | the goose/guangdong-lineage h5 viruses have evolved into diverse clades and subclades based on their hemagglutinin (ha) gene during their circulation in wild birds and poultry. since late 2013, the clade 2.3.4.4 viruses have become widespread in poultry and wild bird populations around the world. different subtypes of the clade 2.3.4.4 h5 viruses, including h5n1, h5n2, h5n6, and h5n8, have caused vast disease outbreaks in poultry in asia, europe, and north america. in this study, we developed a ... | 2016 | 27309064 |
| novel highly pathogenic avian a(h5n2) and a(h5n8) influenza viruses of clade 2.3.4.4 from north america have limited capacity for replication and transmission in mammals. | highly pathogenic influenza a(h5n8) viruses from clade 2.3.4.4 were introduced to north america by migratory birds in the fall of 2014. reassortment of a(h5n8) viruses with avian viruses of north american lineage resulted in the generation of novel a(h5n2) viruses with novel genotypes. through sequencing of recent avian influenza viruses, we identified pb1 and np gene segments very similar to those in the viruses isolated from north american waterfowl prior to the introduction of a(h5n8) to nort ... | 2017 | 27303732 |
| [determination of influenza virus h5n1 and h7n9 using masa technology]. | to set up a new rapid method for the rapid determination of influenza virus h5n1 and h7n9 basing on the multi-analyte suspension array (masa) technology. sequence analysis and design of degenerate primers and specific probes were set in the comparison and analysis of h5, n1, h7 and n9 genes. in combination with masa technology, these primers and probes were used for the determination of samples of h5n1 and h7n9 and other subtypes ( h1n1, ph1n1, h5n2, h3n2 and h9n2). we developed a rapid determin ... | 2015 | 26951004 |
| generation of a reassortant avian influenza virus h5n2 vaccine strain capable of protecting chickens against infection with egyptian h5n1 and h9n2 viruses. | avian influenza h5n1 viruses have been enzootic in egyptian poultry since 2006. avian influenza h9n2 viruses which have been circulating in egyptian poultry since 2011 showed high replication rates in embryonated chicken eggs and mammalian cells. | 2016 | 26620838 |
| adaptation of a mallard h5n2 low pathogenicity influenza virus in chickens with prior history of infection with infectious bursal disease virus. | the influenza a/mallard/pennsylvania/10218/1984 (h5n2) virus is unable to replicate in 3-wk-old immunocompetent specific-pathogen-free chickens when a dose of 5 x 10(6) 50% egg infectious dose/ml is used. in contrast, this mallard virus shows limited replication in 3-wk-old chickens that had been previously infected at 2 days of age with, and recovered from, the immunosuppressive agent infectious bursal disease virus (ibdv; herein referred to as ibdv chickens). this limited replication in ibdv c ... | 2010 | 20521687 |
| pathogenesis and transmission of novel highly pathogenic avian influenza h5n2 and h5n8 viruses in ferrets and mice. | a novel highly pathogenic avian influenza (hpai) h5n8 virus, first detected in january 2014 in poultry and wild birds in south korea, has spread throughout asia and europe and caused outbreaks in canada and the united states by the end of the year. the spread of h5n8 and the novel reassortant viruses, h5n2 and h5n1 (h5nx), in domestic poultry across multiple states in the united states pose a potential public health risk. to evaluate the potential of cross-species infection, we determined the pa ... | 2015 | 26223637 |
| antiviral effects of novel herbal medicine kiom-c, on diverse viruses. | in order to identify new potential antiviral agents, recent studies have advocated thorough testing of herbal medicines or natural substances that are traditionally used to prevent viral infections. antiviral activities and the mechanism of action of the total aqueous extract preparation of kiom-c, a novel herbal medicine, against diverse types of viruses were investigated. in vitro antiviral activity against a/puerto rico/8/34 (h1n1) (pr8), vesicular stomatitis virus (vsv), and newcastle diseas ... | 2015 | 25942440 |
| epimedium koreanum nakai displays broad spectrum of antiviral activity in vitro and in vivo by inducing cellular antiviral state. | epimedium koreanum nakai has been extensively used in traditional korean and chinese medicine to treat a variety of diseases. despite the plant's known immune modulatory potential and chemical make-up, scientific information on its antiviral properties and mode of action have not been completely investigated. in this study, the broad antiviral spectrum and mode of action of an aqueous extract from epimedium koreanum nakai was evaluated in vitro, and moreover, the protective effect against diverg ... | 2015 | 25609307 |
| pandemic preparedness with live attenuated influenza vaccines based on a/leningrad/134/17/57 master donor virus. | continuously evolving avian influenza viruses pose a constant threat to the human public health. in response to this threat, a number of pandemic vaccine candidates have been prepared and evaluated in animal models and clinical trials. this review summarizes the data from the development and preclinical and clinical evaluation of pandemic live attenuated influenza vaccines (laiv) based on russian master donor virus a/leningrad/134/17/57. laiv candidates of h5n1, h5n2, h7n3, h1n1 and h2n2 subtype ... | 2015 | 25555687 |
| antibody response to dna vaccine against h5n1 avian influenza virus in broilers immunized according to three schedules. | broiler type chickens were immunized intramuscularly with a dna vaccine encoding hemagglutinin (ha) from h5n1 avian influenza virus. the chickens were divided into four groups: control group which was not immunized, a group which obtained only one dose, and two groups which were immunized twice, one group with a boost two weeks after the priming and the other four weeks. blood samples were collected at several time points and the dynamics of the humoral response to the vaccine was studied. high ... | 2014 | 25180224 |
| prior infection of pigs with swine influenza viruses is a barrier to infection with avian influenza viruses. | although pigs are susceptible to avian influenza viruses (aiv) of different subtypes, the incidence of aiv infections in the field appears to be low. swine h1n1, h3n2 and h1n2 influenza viruses (siv) are enzootic worldwide and most pigs have antibodies to 1 or more siv subtypes. this study aimed to examine whether infection-immunity to h1n1 or h3n2 siv may (1) protect pigs against subsequent infections with aiv of various haemagglutinin and/or neuraminidase subtypes and/or (2) interfere with the ... | 2010 | 20627621 |
| adjuvant efficacy of momv against avian influenza virus infection in mice. | highly pathogenic avian influenza h5n1 viruses are found chiefly in birds and have caused severe disease and death in infected humans. development of influenza vaccines capable of inducing heterosubtypic immunity against a broad range of influenza viruses is the best option for the preparedness, since vaccination remains the principal method in controlling influenza viral infections. here, a momv-adjuvanted recombinant h5n2 (rh5n2) whole virus antigen vaccine with a/environment/korea/w149/06(h5n ... | 2013 | 24173647 |
| [local antibody immune responses in influenza patients and persons vaccinated with seasonal, pre-pandemic, and pandemic live attenuated influenza vaccines]. | mucosal immunity is one of the most important factors of human anti-influenza defense. the data about local immune responses in influenza a (h3n2) patients and in persons vaccinated within 2000-2009 with different seasonal laivs, a (h1n1)pdm2009 laiv, and a (h5n2) laiv are discussed. the influenza infection resulted in the larger quantities of local iga and igg conversions than seasonal laiv vaccination. 56% of young (18-21 y.o.) persons had high titers (> or = 1:64) of iga to a (h1n1)pdm2009 vi ... | 2016 | 24006632 |
| immunogenicity and protective efficacy of cold-adapted x-31 live attenuated pre-pandemic h5n1 influenza vaccines. | despite global efforts to control influenza viruses, they have taken a heavy toll on human public health worldwide. among particular threats is highly pathogenic avian h5n1 influenza virus (hpai) due to not only its high mortality in humans but also possible human-to-human transmission either through reassortment with other human influenza viruses such as 2009 pandemic h1n1 influenza virus, or by genetic mutations. with the aim of developing effective vaccines against the h5n1 viruses, we genera ... | 2013 | 23742997 |
| [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. | 2010 | 20734718 |
| a rapid and sensitive real-time reverse transcription pcr for the pathotyping of south african h5n2 avian influenza viruses. | a fluorescence resonance energy transfer (fret) real-time reverse-transcription (rrt-pcr) assay was developed that distinguishes stains of south african and european highly pathogenic (hpai) from low pathogenicity (lpai) h5 avian influenza viruses in the absence of virus isolation, irrespective of the length of insertion at the hemagglutinin cleavage site (h0). the assay was used to pathotype h5-type viruses detected by rrt-pcr in ostrich tracheal swabs collected during the 2006 hpai h5n2 outbre ... | 2008 | 19294990 |
| prior infection of chickens with h1n1 avian influenza virus elicits heterologous protection against highly pathogenic h5n2. | current vaccines for influenza are primarily killed whole virus vaccines that elicit antibody responses to the homologous virus but lack protection against heterologous viruses. using chickens as a model we have explored the possibility of using a live low pathogenic avian influenza (lpai) a/goose/ab/223/2005 h1n1 virus as a vaccine to generate protective immunity against heterologous highly pathogenic avian influenza (hpai) a/chicken/pensylvania/1370/1983 h5n2 virus challenge. virus replicated ... | 2012 | 23084852 |
| evaluation of the efficacy of a pre-pandemic h5n1 vaccine (mg1109) in mouse and ferret models. | the threat of a highly pathogenic avian influenza (hpai) h5n1 virus causing the next pandemic remains a major concern. in this study, we evaluated the immunogenicity and efficacy of an inactivated whole-virus h5n1 pre-pandemic vaccine (mg1109) formulated by green cross co., ltd containing the hemagglutinin (ha) and neuraminidase (na) genes of the clade 1 a/vietnam/1194/04 virus in the backbone of a/puerto rico/8/34 (rgvietnam/04xpr8/34). administration of the mg1109 vaccine (2-doses) in mice and ... | 2012 | 22752912 |
| molecular characterization of low pathogenic avian influenza viruses, isolated from food products imported into singapore. | we have completed the genetic characterization of all eight gene segments for four low pathogenic avian influenza (lpai) viruses. the objective of this study was to detect the presence of novel signatures that may serve as early warning indicators of the conversion of lpai viruses to high pathogenic avian influenza (hpai) viruses. this study included three h5n2 and one h5n3 viruses that were isolated from live poultry imported into singapore as part of the national avian influenza virus (aiv) su ... | 2009 | 19464126 |
| an evaluation of avian influenza diagnostic methods with domestic duck specimens. | monitoring of poultry, including domestic ducks, for avian influenza (ai) virus has increased considerably in recent years. however, the current methods validated for the diagnosis and detection of ai virus infection in chickens and turkeys have not been evaluated for performance with samples collected from domestic ducks. in order to ensure that methods for the detection of ai virus or ai virus antibody will perform acceptably well with these specimens, samples collected from domestic ducks exp ... | 2009 | 19630236 |
| cold-adapted pandemic 2009 h1n1 influenza virus live vaccine elicits cross-reactive immune responses against seasonal and h5 influenza a viruses. | the rapid transmission of the pandemic 2009 h1n1 influenza virus (ph1n1) among humans has raised the concern of a potential emergence of reassortment between ph1n1 and highly pathogenic influenza strains, especially the avian h5n1 influenza virus. here, we report that the cold-adapted ph1n1 live attenuated vaccine (caph1n1) elicits cross-reactive immunity to seasonal and h5 influenza a viruses in the mouse model. immunization with caph1n1 induced both systemic and mucosal antibodies with broad r ... | 2012 | 22438541 |
| co-administration of inactivated avian influenza virus with cpg or ril-2 strongly enhances the local immune response after intranasal immunization in chicken. | intranasal delivery of vaccines is the most effective means of inducing effective immunity in the upper respiratory tract as well as other mucosal lymphoid tissues. to evaluate the effects of the h5n2 inactivated virus with adjuvant, 120 one-day-old chicks were intranasal immunized with the h5n2 inactivated virus respectively mixed with adjuvant cpg or recombinant il-2 (ril-2). the local immunocompetent cells on the respiratory tract were detected. the results showed that the number of intraepit ... | 2009 | 19647063 |
| comparative pathogenesis of an avian h5n2 and a swine h1n1 influenza virus in pigs. | pigs are considered intermediate hosts for the transmission of avian influenza viruses (aivs) to humans but the basic organ pathogenesis of aivs in pigs has been barely studied. we have used 42 four-week-old influenza naive pigs and two different inoculation routes (intranasal and intratracheal) to compare the pathogenesis of a low pathogenic (lp) h5n2 aiv with that of an h1n1 swine influenza virus. the respiratory tract and selected extra-respiratory tissues were examined for virus replication ... | 2009 | 19684857 |
| [testing of apathogenic influenza virus h5n3 as a poultry live vaccine]. | four h5n2 experimental vaccine strains and the apathogenic wild duck h5n3 influenza virus a/duck/ moscow/4182/2010 (dk/4182) were tested as a live poultry vaccine. experimental strains had the hemagglutinin of the a/vietnam/1203/04 strain lacking the polybasic ha cleavage site or the hemagglutinin from attenuated virus (ku/ at) that was derived from the highly pathogenic influenza virus a/chicken/kurgan/3/2005 (h5n1). the hemagglutinin of the ku-at has the amino acid substitutions asp54/asn and ... | 2015 | 26665435 |
| genetic stability of live attenuated vaccines against potentially pandemic influenza viruses. | ensuring genetic stability is a prerequisite for live attenuated influenza vaccine (laiv). this study describes the results of virus shedding and clinical isolates' testing of phase i clinical trials of russian laivs against potentially pandemic influenza viruses in healthy adults. | 2015 | 26432909 |
| [evaluation of the anti-neuraminidase antibodies in clinical trials of the live influenza vaccine of the a(h5n2) subtype]. | in the current study, we evaluated the neuraminidase-inhibition (ni) antibodies among volunteers during the phase i and phase ii of the clinical trials of a monovalent live attenuated influenza vaccine (laiv) a/17/duck/ potsdam/86/92(h5n2). the reassortant influenza virus rn2/57-human a(h7n2) containing neuraminidase (na) from the a/leningrad/134/17/57(h2n2) was used in ni test. it was shown that two doses of the monovalent laiv a(h5n2) led to a statistically significant increase in the ni antib ... | 2016 | 24772644 |
| thermal inactivation of h5n2 high-pathogenicity avian influenza virus in dried egg white with 7.5% moisture. | high-pathogenicity avian influenza viruses (hpaiv) cause severe systemic disease with high mortality in chickens. isolation of hpaiv from the internal contents of chicken eggs has been reported, and this is cause for concern because hpaiv can be spread by movement of poultry products during marketing and trade activity. this study presents thermal inactivation data for the hpaiv strain a/chicken/pa/1370/83 (h5n2) (pa/83) in dried egg white with a moisture content (7.5%) similar to that found in ... | 2009 | 19777906 |
| tenacity of low-pathogenic avian influenza viruses in different types of poultry litter. | to determine the risk of infection associated with exposure to low-pathogenic avian influenza (ai) virus-contaminated poultry litter, the tenacity of low pathogenic a/ck/ca/431/00(h6n2), a/mallard/mn/355779/00(h5n2), and a/turkey/ohio/313053/04(h3n2) was evaluated. viral stocks were incubated with poultry litter from commercial flocks at 25°c. three types of poultry litter, wood shavings, shavings plus gypsum, and shavings plus peanut hulls, from commercial broiler flocks were used. the 3 low-pa ... | 2012 | 22802163 |
| serological survey for avian influenza in turkeys in three states of southwest nigeria. | since the first outbreak of avian influenza (ai) in nigeria in 2006, there has been continuous monitoring of the disease in chickens with little attention given to turkeys. as part of on-going surveillance for ai in southwest nigeria, we used a competitive elisa to detect anti-ai virus antibodies in 520 turkey sera obtained from poultry farms in oyo, osun, and ondo states while haemagglutination inhibiting antibodies against low pathogenic ai viruses (lpaivs) were detected using h3n8 and h5n2 su ... | 2015 | 26664747 |
| 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- ... | 2011 | 21739555 |
| emerging highly pathogenic h5 avian influenza viruses in france during winter 2015/16: phylogenetic analyses and markers for zoonotic potential. | several new highly pathogenic (hp) h5 avian influenza virus (aiv) have been detected in poultry farms from south-western france since november 2015, among which an hp h5n1. the zoonotic potential and origin of these aivs immediately became matters of concern. one virus of each subtype h5n1 (150169a), h5n2 (150233) and h5n9 (150236) was characterised. all proved highly pathogenic for poultry as demonstrated molecularly by the presence of a polybasic cleavage site in their ha protein - with a sequ ... | 2017 | 28277218 |
| isolation and genetic characterization of a novel 2.2.1.2a h5n1 virus from a vaccinated meat-turkeys flock in egypt. | vaccination of poultry to control highly pathogenic avian influenza virus (hpaiv) h5n1 is used in several countries. hpaiv h5n1 of clade 2.2.1 which is endemic in egypt has diversified into two genetic clades. clade 2.2.1.1 represents antigenic drift variants in vaccinated commercial poultry while clade 2.2.1.2 variants are detected in humans and backyard poultry. little is known about h5n1 infection in vaccinated turkeys under field conditions. | 2017 | 28274236 |
| vaccine efficacy of inactivated, chimeric hemagglutinin h9/h5n2 avian influenza virus and its suitability for the marker vaccine strategy. | in order to produce a dually effective vaccine against h9 and h5 avian influenza viruses that aligns with the diva (differentiating infected from vaccinated animals) strategy, we generated a chimeric h9/h5n2 recombinant vaccine that expressed the whole ha1 region of a/ck/korea/04163/04 (h9n2) and the ha2 region of recent highly pathogenic avian influenza (hpai) a/md/korea/w452/14 (h5n8) viruses. the chimeric h9/h5n2 virus showed in vitro and in vivo growth properties and virulence that were simi ... | 2017 | 28077631 |
| genesis and dissemination of highly pathogenic h5n6 avian influenza viruses. | clade 2.3.4.4 highly pathogenic avian influenza viruses (h5nx) have spread from asia to other parts of the world. since 2014, human infections with clade 2.3.4.4 highly pathogenic avian influenza h5n6 viruses have been continuously reported in china. to investigate the genesis of the virus, we analyzed 123 h5 or n6 environmental viruses sampled from live-poultry markets or farms from 2012 to 2015 in mainland china. our results indicated that clade 2.3.4.4 h5n2/n6/n8 viruses shared the same hemag ... | 2017 | 28003485 |
| virus-like particles displaying h5, h7, h9 hemagglutinins and n1 neuraminidase elicit protective immunity to heterologous avian influenza viruses in chickens. | avian influenza (ai) viruses circulating in wild birds pose a serious threat to public health. human and veterinary vaccines against ai subtypes are needed. here we prepared triple-subtype vlps that co-localized h5, h7 and h9 antigens derived from h5n1, h7n3 and h9n2 viruses. vlps also contained influenza n1 neuraminidase and retroviral gag protein. the h5/h7/h9/n1/gag vlps were prepared using baculovirus expression. biochemical, functional and antigenic characteristics were determined including ... | 2017 | 27936463 |
| the response of mute swans (cygnus olor, gm. 1789) to vaccination against avian influenza with an inactivated h5n2 vaccine. | recent epidemics of highly pathogenic avian influenza (hpai) produced an unprecedented number of cases in mute swans (cygnus olor) in european countries, which indicates that these birds are very sensitive to the h5n1 virus. the hpai outbreaks stirred a debate on the controversial stamping-out policy in populations of protected bird species. after preventive vaccination had been approved in the european union, several countries have introduced vaccination schemes to protect poultry, captive wild ... | 2016 | 27770803 |
| protective efficacy of a prime-boost protocol using h5-dna plasmid as prime and inactivated h5n2 vaccine as the booster against the egyptian avian influenza challenge virus. | in this study, a recombinant dna plasmid was constructed, encoding for ha1 of a selected egyptian h5n1 virus (isolated during the 2012 outbreaks). in the immunization and challenge experiments, spf chickens received 1 or 2 doses of h5-dna plasmid prime, and boosted with the inactivated h5n2 vaccine. haemagglutination inhibition (hi) titers, protection levels, and the magnitude of virus shedding were compared to that of the chickens that received either dna plasmid or inactivated h5n2 vaccine alo ... | 2017 | 27640441 |
| changes in adaptation of h5n2 highly pathogenic avian influenza h5 clade 2.3.4.4 viruses in chickens and mallards. | h5n2 highly pathogenic avian influenza (hpai) viruses caused a severe poultry outbreak in the united states (u.s.) during 2015. in order to examine changes in adaptation of this viral lineage, the infectivity, pathogenicity and transmission of poultry h5n2 viruses were investigated in chickens and mallards in comparison to the wild duck 2014 u.s. index h5n2 virus. the four poultry isolates examined had a lower mean bird infectious dose than the index virus but still transmitted poorly to direct ... | 2016 | 27632565 |
| 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 ... | 2011 | 21872621 |
| epidemiological and evolutionary inference of the transmission network of the 2014 highly pathogenic avian influenza h5n2 outbreak in british columbia, canada. | the first north american outbreak of highly pathogenic avian influenza (hpai) involving a virus of eurasian a/goose/guangdong/1/1996 (h5n1) lineage began in the fraser valley of british columbia, canada in late november 2014. a total of 11 commercial and 1 non-commercial (backyard) operations were infected before the outbreak was terminated. control measures included movement restrictions that were placed on a total of 404 individual premises, 150 of which were located within a 3 km radius of an ... | 2016 | 27489095 |
| pathobiology of highly pathogenic avian influenza virus h5n2 infection in juvenile ostriches from south africa. | in 2011, over 35,000 ostriches were slaughtered in the oudtshoorn district of the western cape province of south africa following the diagnosis of highly pathogenic avian influenza virus h5n2. we describe the pathology and virus distribution via immunohistochemistry in juvenile birds that died rapidly in this outbreak after showing signs of depression and weakness. associated sialic acid (sa) receptor distribution in uninfected birds is also described. at necropsy, enlarged spleens, swollen live ... | 2012 | 23402120 |
| novel avian influenza a (h5n6) viruses isolated in migratory waterfowl before the first human case reported in china, 2014. | in may 2014, china formally confirmed the first human infection with the novel h5n6 avian influenza virus (aiv) in sichuan province. before the first human case was reported, surveillance of aivs in wild birds resulted in the detection of three h5n6 viruses in faecal samples from migratory waterfowl in chenhu wetlands, hubei province, china. genetic and phylogenetic analyses revealed that these three novel viruses were closely related to the h5n6 virus that has caused human infections in china s ... | 2016 | 27431568 |
| formatted single-domain antibodies can protect mice against infection with influenza virus (h5n2). | this work continues a series of recently published studies that employ recombinant single-domain antibody (sdab, or nanobody®) generation technologies to battle viruses by a passive immunization approach. as a proof of principle, we describe a modified technique to efficiently generate protective molecules against a particular strain of influenza virus within a reasonably short period of time. this approach starts with the immunization of a camel (camelus bactrianus) with the specified antigen-e ... | 2012 | 23274623 |
| heterosubtypic protective immunity against widely divergent influenza subtypes induced by fusion protein 4sm2 in balb/c mice. | regular reformulation of currently available vaccines is necessary due to the unpredictable variability of influenza viruses. therefore, vaccine based on a highly conserved antigen with capability of induction of effective immune responses could be a potential solution. influenza matrix protein-2 (m2) is highly conserved across influenza subtypes and a promising candidate for a broadly protective influenza vaccine. for the enhancement of broad protection, four tandem copies of consensus m2 gene ... | 2014 | 24502341 |
| prevalence and characterization of influenza viruses in diverse species in los llanos, colombia. | while much is known about the prevalence of influenza viruses in north america and eurasia, their prevalence in birds and mammals in south america is largely unknown. to fill this knowledge gap and provide a baseline for future ecology and epidemiology studies, we conducted 2 years of influenza surveillance in the eastern plains (los llanos) region of colombia. real-time reverse transcriptase polymerase chain reaction (rt-pcr) identified influenza viruses in wild birds, domestic poultry, swine a ... | 2013 | 26038461 |
| inhibitory effects of an aqueous extract from cortex phellodendri on the growth and replication of broad-spectrum of viruses in vitro and in vivo. | cortex phellodendri (c. phellodendri), the dried trunk bark of phellodendron amurense ruprecht, has been known as a traditional herbal medicine, showing several bioactivities. however, antiviral activity of c. phellodendri aqueous extract (cp) not reported in detail, particularly aiming the prophylactic effectiveness. | 2016 | 27484768 |
| interferon-mediated antiviral activities of angelica tenuissima nakai and its active components. | angelica tenuissima nakai is a widely used commodity in traditional medicine. nevertheless, no study has been conducted on the antiviral and immune-modulatory properties of an aqueous extract of angelica tenuissima nakai. in the present study, we evaluated the antiviral activities and the mechanism of action of an aqueous extract of angelica tenuissima nakai both in vitro and in vivo. in vitro, an effective dose of angelica tenuissima nakai markedly inhibited the replication of influenza a virus ... | 2016 | 26727903 |
| enzootic genotype s of h9n2 avian influenza viruses donates internal genes to emerging zoonotic influenza viruses in china. | avian influenza viruses of subtype h9n2 are widely prevalent in poultry in many asian countries, and the segmented nature of the viral genome results in multiple distinct genotypes via reassortment. in this study, genetic evolution of h9n2 viruses circulating in eastern china during 2007-2013 was analyzed. the results showed that the diversity of the gene constellations generated six distinct genotypes, in which a novel genotype (s) bearing the backbone of a/chicken/shanghai/f/98-like viruses by ... | 2014 | 25457363 |
| is the optimal ph for membrane fusion in host cells by avian influenza viruses related to host range and pathogenicity? | influenza viruses isolated from wild ducks do not replicate in chickens. this fact is not explained solely by the receptor specificity of the hemagglutinin (ha) from such viruses for target host cells. to investigate this restriction in host range, the fusion activities of ha molecules from duck and chicken influenza viruses were examined. influenza viruses a/duck/mongolia/54/2001 (h5n2) (dk/mng) and a/chicken/ibaraki/1/2005 (h5n2) (ck/ibr), which replicate only in their primary hosts, were used ... | 2016 | 27231009 |
| novel highly pathogenic avian h5 influenza a viruses in live poultry markets, wuxi city, china, 2013-2014. | during 12 recent months of periodic influenza virus surveillance at 9 live poultry markets in wuxi city china, we identified multiple highly pathogenic h5n6, h5n8, h5n2, and h5n1 avian influenza viruses. the variety of potentially pandemic viruses in this low-risk area is disconcerting and portends an increased pandemic threat. | 2016 | 27186580 |
| fatal influenza a (h5n1) virus infection in zoo-housed tigers in yunnan province, china. | from 2014 to 2015, three cases of highly pathogenic avian influenza infection occurred in zoo-housed north-east china tigers (panthera tigris ssp.altaica) and four tigers died of respiratory distress in succession in yunnan province, china. we isolated and characterized three highly pathogenic avian influenza a(h5n1) viruses from these tigers. phylogenetic analysis indicated that a/tiger /yunnan /tig1404 /2014(h5n1) belongs to the provisional subclade 2.3.4.4e which were novel reassortant influe ... | 2016 | 27162026 |
| highly pathogenic avian influenza h5n6 viruses exhibit enhanced affinity for human type sialic acid receptor and in-contact transmission in model ferrets. | since may 2014, highly pathogenic avian influenza h5n6 virus has been reported to cause six severe human infections three of which were fatal. the biological properties of this subtype, in particular its relative pathogenicity and transmissibility in mammals, are not known. we characterized the virus receptor-binding affinity, pathogenicity, and transmissibility in mice and ferrets of four h5n6 isolates derived from waterfowl in china from 2013-2014. all four h5n6 viruses have acquired a binding ... | 2016 | 27122581 |
| genedia multi influenza ag rapid test for detection and h1, h3, and h5 subtyping of influenza viruses. | rapid identification and subtype determination of influenza virus is important in managing infected patients. rapid influenza diagnostic tests (ridts) are widely used in this manner, but most can only detect influenza a and b viruses without subtyping. a new ridt, genedia multi influenza ag rapid test (genedia), was developed for detection of influenza a and b viruses and also subtyping of influenza a to h1, h3, h5 which has not been possible with other ridts. | 2015 | 26540461 |
| anti-influenza activity of alchemilla mollis extract: possible virucidal activity against influenza virus particles. | influenza virus infection is a major public health problem that leads to significant morbidity and mortality. the emergence of resistance to the currently available anti-influenza agents has necessitated the development of new drugs with novel targets. studying known ethno-medicinal plants is a promising approach for the discovery of new antiviral compounds. alchemilla mollis is used in traditional medicine in europe for different indications, including minimizing the symptoms of a sore throat. ... | 2013 | 24270383 |
| a cationic liposome-dna complexes adjuvant (jvrs-100) enhances the immunogenicity and cross-protective efficacy of pre-pandemic influenza a (h5n1) vaccine in ferrets. | influenza a (h5n1) viruses continue to pose a public health threat. as inactivated h5n1 vaccines are poorly immunogenic, adjuvants are needed to improve the immunogenicity of h5n1 vaccine in humans. here, we investigated the immunogenicity and cross-protective efficacy in ferrets of a clade 2.2-derived vaccine with addition of jvrs-100, an adjuvant consisting of cationic liposome-dna complexes (cldc). after the first vaccination, significantly higher levels of hemagglutination-inhibition (hai) a ... | 2016 | 26967975 |
| evidence for common ancestry among viruses isolated from wild birds in beringia and highly pathogenic intercontinental reassortant h5n1 and h5n2 influenza a viruses. | highly pathogenic clade 2.3.4.4 h5n8, h5n2, and h5n1 influenza a viruses were first detected in wild, captive, and domestic birds in north america in november-december 2014. in this study, we used wild waterbird samples collected in alaska prior to the initial detection of clade 2.3.4.4 h5 influenza a viruses in north america to assess the evidence for: (1) dispersal of highly pathogenic influenza a viruses from east asia to north america by migratory birds via alaska and (2) ancestral origins o ... | 2016 | 26944444 |
| characterization of clade 2.3.4.4 highly pathogenic h5 avian influenza viruses in ducks and chickens. | worldwide dissemination of reassortant variants of h5 clade 2.3.4.4 highly pathogenic avian influenza (hpai) viruses has posed a great threat to the poultry industry. here, we systematically characterized the h5n2, h5n6 and h5n8 influenza viruses in poultry and compared them with those of previous clade 2.3.4 h5n1 virus. all the three h5 subtype reassortants caused systematic infection in ducks, and exhibited efficient direct transmission in ducks. all of them were highly pathogenic in chickens; ... | 2016 | 26711037 |
| assessment of immune responses to h5n1 inactivated influenza vaccine among individuals previously primed with h5n2 live attenuated influenza vaccine. | during the past decade, a number of h5 subtype influenza vaccines have been developed and tested in clinical trials, but most of them induced poor serum antibody responses prompting the evaluation of novel vaccination approaches. one of the most promising ones is a "prime-boost" strategy, which could result in the induction of prompt and robust immune responses to a booster influenza vaccine following priming with homologous or heterologous vaccine strains. in our study we evaluated immunogenici ... | 2015 | 26697973 |
| identification and characterization of a highly pathogenic h5n1 avian influenza a virus during an outbreak in vaccinated chickens in egypt. | highly pathogenic avian influenza a (hpai) h5n1 viruses continue to be a major veterinary and public health problem in egypt. continued surveillance of these viruses is necessary to devise strategies to control the spread of the virus and to monitor its evolutionary patterns. this is a report of the identification of a variant strain of hpai h5n1 virus during an outbreak in 2010 in vaccinated chicken flocks in a poultry farm in assiut, egypt. vaccination of chickens with an oil-emulsified inacti ... | 2015 | 26363196 |
| adaptive mutations in pb2 gene contribute to the high virulence of a natural reassortant h5n2 avian influenza virus in mice. | the highly pathogenic a/chicken/hebei/1102/2010 (hb10) h5n2 virus is a natural reassortant derived from circulating h5n1 and endemic h9n2 avian influenza viruses (aiv). to evaluate the potential of its interspecies transmission, we previously serially passaged the non-virulent hb10 virus in the mouse lung and obtained a high virulence variant (hb10-ma). genomic sequencing revealed five mutations (ha-s227n, pb2-q591k, pb2-d701n, pa-i554v and np-r351k) that distinguished hb10-ma virus from its par ... | 2015 | 26315686 |
| a comparative analysis of host responses to avian influenza infection in ducks and chickens highlights a role for the interferon-induced transmembrane proteins in viral resistance. | chickens are susceptible to infection with a limited number of influenza a viruses and are a potential source of a human influenza pandemic. in particular, h5 and h7 haemagglutinin subtypes can evolve from low to highly pathogenic strains in gallinaceous poultry. ducks on the other hand are a natural reservoir for these viruses and are able to withstand most avian influenza strains. | 2015 | 26238195 |
| serial passage in ducks of a low-pathogenic avian influenza virus isolated from a chicken reveals a high mutation rate in the hemagglutinin that is likely due to selection in the host. | a comparative study of the ability of three low-pathogenic avian influenza virus (lpaiv) isolates to be transmitted from duck to duck was performed. pekin ducks were inoculated with two lpaiv isolates from chickens (a/ck/pa/13609/93 [h5n2], h5n2-ck; a/ck/tx/167280-4/02 [h5n3], h5n3-ck) and one isolate from a wild bird (a/mute swan/ mi/451072/06 [h5n1], h5n1-wb). during the establishment of the passage model, only two viruses (h5n1, h5n2) were able to be transmitted from duck to duck. transmissio ... | 2015 | 26179620 |
| nomenclature updates resulting from the evolution of avian influenza a(h5) virus clades 2.1.3.2a, 2.2.1, and 2.3.4 during 2013-2014. | the a/goose/guangdong/1/96-like hemagglutinin (ha) genes of highly pathogenic avian influenza (hpai) a(h5) viruses have continued to rapidly evolve since the most recent update to the h5 clade nomenclature by the who/oie/fao h5n1 evolution working group. new clades diverging beyond established boundaries need to be identified and designated accordingly. | 2015 | 25966311 |
| development of a dual-protective live attenuated vaccine against h5n1 and h9n2 avian influenza viruses by modifying the ns1 gene. | an increasing number of outbreaks of avian influenza h5n1 and h9n2 viruses in poultry have caused serious economic losses and raised concerns for human health due to the risk of zoonotic transmission. however, licensed h5n1 and h9n2 vaccines for animals and humans have not been developed. thus, to develop a dual h5n1 and h9n2 live-attenuated influenza vaccine (laiv), the ha and na genes from a virulent mouse-adapted avian h5n2 (a/wb/korea/ma81/06) virus and a recently isolated chicken h9n2 (a/ck ... | 2015 | 25959557 |
| emergence of novel clade 2.3.4 influenza a (h5n1) virus subgroups in yunnan province, china. | from december 2013 to march 2014, a major wave of highly pathogenic avian influenza outbreak occurred in poultry in yunnan province, china. we isolated and characterized eight highly pathogenic avian influenza a (h5n1) viruses from poultry. full genome influenza sequences and analyses have been performed. sequence analyses revealed that they belonged to clade 2.3.4 but did not fit within the three defined subclades. the isolated viruses were provisional subclade 2.3.4.4e. the provisional subclad ... | 2015 | 25917492 |
| genetic evolution of h5 highly pathogenic avian influenza virus in domestic poultry in vietnam between 2011 and 2013. | in spite of highly pathogenic avian influenza h5n1 vaccination campaigns for domestic poultry, h5n1 viruses continue to circulate in vietnam. to estimate the prevalence of avian influenza virus in vietnam, surveillance was conducted between november 2011 and february 2013. genetic analysis of 312 highly pathogenic avian influenza h5 viruses isolated from poultry in vietnam was conducted and possible genetic relationships with strains from neighboring countries were investigated. as previously re ... | 2015 | 25743422 |
| genomic and phylogenetic characterization of novel, recombinant h5n2 avian influenza virus strains isolated from vaccinated chickens with clinical symptoms in china. | infection of poultry with diverse lineages of h5n2 avian influenza viruses has been documented for over three decades in different parts of the world, with limited outbreaks caused by this highly pathogenic avian influenza virus. in the present study, three avian h5n2 influenza viruses, a/chicken/shijiazhuang/1209/2013, a/chicken/chiping/0321/2014, and a/chicken/laiwu/0313/2014, were isolated from chickens with clinical symptoms of avian influenza. complete genomic and phylogenetic analyses demo ... | 2015 | 25723387 |
| impact of vaccination on infection with vietnam h5n1 high pathogenicity avian influenza virus in hens and the eggs they lay. | high pathogenicity avian influenza virus (hpaiv) infections in chickens negatively impact egg production and cause egg contamination. previously, vaccination maintained egg production and reduced egg contamination when challenged with a north american h5n2 hpaiv. however, asian h5n1 hpaiv infection has some characteristics of increased pathogenicity compared to other h5 hpaiv such as more rapid drop and complete cessation in egg production. sham (vaccinated at 25 and 28 weeks of age), inactivate ... | 2015 | 25657093 |
| outbreaks of avian influenza a (h5n2), (h5n8), and (h5n1) among birds--united states, december 2014-january 2015. | during december 15, 2014-january 16, 2015, the u.s. department of agriculture received 14 reports of birds infected with asian-origin, highly pathogenic avian influenza a (hpai) (h5n2), (h5n8), and (h5n1) viruses. these reports represent the first reported infections with these viruses in u.s. wild or domestic birds. although these viruses are not known to have caused disease in humans, their appearance in north america might increase the likelihood of human infection in the united states. human ... | 2015 | 25654614 |
| vaccine protection of chickens against antigenically diverse h5 highly pathogenic avian influenza isolates with a live hvt vector vaccine expressing the influenza hemagglutinin gene derived from a clade 2.2 avian influenza virus. | vaccination is an important tool in the protection of poultry against avian influenza (ai). for field use, the overwhelming majority of ai vaccines produced are inactivated whole virus formulated into an oil emulsion. however, recombinant vectored vaccines are gaining use for their ability to induce protection against heterologous isolates and ability to overcome maternal antibody interference. in these studies, we compared protection of chickens provided by a turkey herpesvirus (hvt) vector vac ... | 2015 | 25613723 |
| adaptation of a natural reassortant h5n2 avian influenza virus in mice. | it is reported that the h5n2 highly pathogenic avian influenza virus a/chicken/hebei/1102/2010 (hb10) is a natural reassortant between circulating h5n1 and endemic h9n2 influenza viruses. to evaluate the potential of its interspecies transmission, the wild-type hb10 was adapted in mice through serial lung passages. increased virulence was detectable in 5 sequential lung passages in mice and a highly virulent mouse-adapted strain (hb10-ma) with a 50% mouse lethal dose of 10(2.5) 50% egg infectiou ... | 2014 | 25037995 |
| bird to human transmission biases and vaccine escape mutants in h5n1 infections. | the avian influenza a h5n1 virus occasionally infects humans, with high mortality rates. although all current human infections are from avian-to-human transmission, it has been shown that h5n1 can be evolved to transmit between mammals, and is therefore a pandemic threat. for h5n1 surveillance, it is of interest to identify the avian isolates most likely to infect humans. in this study, we develop a method to identify mutations significantly associated with avian to human transmission. | 2014 | 24988306 |
| broad cross-reactive epitopes of the h5n1 influenza virus identified by murine antibodies against the a/vietnam/1194/2004 hemagglutinin. | there is an urgent need for a rapid diagnostic system to detect the h5 subtype of the influenza a virus. we previously developed monoclonal antibodies (mabs) against the h5 hemagglutinin (ha) for use in a rapid diagnostic kit. in this study, we determined the epitopes of the anti-h5 ha murine mabs om-b, ay-2c2, and yh-1a1. binding assays of the mabs to different strains of h5 has indicated that om-b and ay-2c2 cross-reacted with has from clades 1, 2.1.3.2, 2.2, and 2.3.4, whereas yh-1a1 failed t ... | 2014 | 24945805 |
| h5-based dna constructs derived from selected highly pathogenic h5n1 avian influenza virus induce high levels of humoral antibodies in muscovy ducks against low pathogenic viruses. | h5 low pathogenic avian influenza virus (lpaiv) infection in domestic ducks is a major problem in duck producing countries. their silent circulation is an ongoing source of potential highly pathogenic or zoonotic emerging strains. to prevent such events, vaccination of domestic ducks might be attempted but remains challenging. currently licensed vector vaccines derived from h5n1 hpaiv possess clade 0, clade 2.2 or clade 2.3.4 ha sequences: selection of the best ha candidate inducing the largest ... | 2014 | 24762011 |
| cleavage site stability of egyptian highly pathogenic avian influenza viruses in backyard chickens during 2009-2011. | two distinguishable subclades of h5n1 (classic and variant strains) are cocirculating among the poultry populations in egypt despite the intensive vaccination programs. a study to investigate the genetic relationship between avian influenza virus (aiv) isolates from backyard chickens in sharkia (2009-2011), subclades, and commercially available vaccines was carried out. | 2015 | 24560697 |
| 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 ... | 2013 | 24080350 |
| the characterization of low pathogenic avian influenza viruses isolated from wild birds in northern vietnam from 2006 to 2009. | due to concerns that wild birds could possibly spread h5n1 viruses, surveillance was conducted to monitor the types of avian influenza viruses circulating among the wild birds migrating to or inhabiting in northern vietnam from 2006 to 2009. an h5n2 virus isolated from a eurasian woodcock had a close phylogenetic relationship to h5 viruses recently isolated in south korea and japan, suggesting that h5n2 has been shared between vietnam, south korea, and japan. an h9n2 virus isolated from a chines ... | 2013 | 24054984 |
| genetic analysis of an h5n2 highly pathogenic avian influenza virus isolated from a chicken in a live bird market in northern vietnam in 2012. | in august 2012, a/chicken/vietnam/oie-2215/2012 (h5n2) was isolated from a chicken in a live bird market (lbm) in northern vietnam. intravenous pathogenicity test revealed that this virus is highly pathogenic in chickens. the pa, ha, np and m, pb2 and na, and pb1 and ns genes of the isolate were phylogenetically closely related to those of a/duck/vietnam/oie-2202/2012 (h5n1) of clade 2.3.2.1, a/chicken/vietnam/oie-1611/2012 (h9n2) and a/chicken/vietnam/oie-2468/2012 (h9n2), respectively. all of ... | 2014 | 23986117 |
| complete genome sequence of avian influenza virus a/chicken/jiangsu/1001/2013(h5n2), demonstrating continuous reassortance of h5n2 in china. | avian influenza virus a/chicken/jiangsu/1001/2013(h5n2) was identified from a healthy chicken in an eastern china poultry market. whole-genome analysis demonstrated that the h5n2 virus originated from a reassortance between a previous a/chicken/hebei/1102/2010(h5n2) virus and an endemic h5n1 virus. the results indicated that continuing reassortance of h5n2 has been occurring in domestic poultry of china. | 2013 | 23868124 |
| selection and characterization of dna aptamers for use in detection of avian influenza virus h5n1. | aptamers are artificial oligonucleotides (dna or rna) that can bind to a broad range of targets. in diagnostic and detection assays, aptamers represent an alternative to antibodies as recognition agents. the objective of this study was to select and characterize dna aptamers that can specifically bind to avian influenza virus (aiv) h5n1 based on systematic evolution of ligands by exponential enrichment (selex) and surface plasmon resonance (spr). the selection was started with an ssdna (single-s ... | 2013 | 23523887 |
| proteins of duck influenza virus responsible for acquisition of pathogenicity in chickens. | influenza virus rgvac1sub-p0 (h5n1) (rgvac1-p0), in which a pair of dibasic amino acid residues was introduced at the cleavage site of the ha of a reassortant of h5n2 and h7n1 viruses of duck origin, was low pathogenic in chickens. vac1sub-p3 (h5n1) (vac1-p3) was selected as a highly pathogenic avian influenza virus by 3 consecutive passages in chickens from low pathogenic strain rgvac1-p0. comparison of amino acid sequences of the virus proteins and experimental infection of chickens with a ser ... | 2013 | 23434880 |
| 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 ... | 2013 | 23324567 |
| 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 ... | 2012 | 23166246 |
| 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 ... | 2012 | 23087121 |
| 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 ... | 2012 | 23049973 |
| 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 ... | 2012 | 22592261 |
| antiviral activity of stachyflin on influenza a viruses of different hemagglutinin subtypes. | the hemagglutinin (ha) of influenza viruses is a possible target for antiviral drugs because of its key roles in the initiation of infection. although it was found that a natural compound, stachyflin, inhibited the growth of h1 and h2 but not h3 influenza viruses in mdck cells, inhibitory activity of the compound has not been assessed against h4-h16 influenza viruses and the precise mechanism of inhibition has not been clarified. | 2013 | 23587221 |
| 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 ... | 2010 | 21172021 |
| 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 ... | 2011 | 21286706 |
| 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 ... | 2011 | 21301183 |
| [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 ... | 2011 | 21446167 |