| immunopathological immunohistochemical study of low pathogenic avian influenza virus h5n1 infection in lovebirds (agapornis spp.) in indonesia. | to date, persistent infection with low pathogenic avian influenza virus (aiv) subtype h5n1 (lpai h5n1) in chickens is widespread in indonesia. commercially available ornamental birds on markets play an important role in triggering the occurrence of aiv outbreaks. thus, the presence of aiv in ornamental birds such as lovebirds needs to be closely monitored. here, the presence of lpai h5n1 was investigated in lovebirds with no clinical signs that, although apparently healthy, can be a continuous s ... | 2019 | 31749584 |
| mouse-adapted h9n2 avian influenza virus causes systemic infection in mice. | h9n2 influenza viruses continuously circulate in multiple avian species and are repeatedly transmitted to humans, posing a significant threat to public health. to investigate the adaptation ability of h9n2 avian influenza viruses (aivs) to mammals and the mutations related to the host switch events, we serially passaged in mice two h9n2 viruses of different ha lineages - a/quail/hong kong/g1/97 (g1) of the g1-like lineage and a/chicken/shandong/zb/2007 (zb) of the bj/94-like lineage -and generat ... | 2019 | 31718675 |
| comparative pathogenicity and transmissibility of the h7n9 highly pathogenic avian influenza virus and the h7n9 low pathogenic avian influenza virus in chickens. | there were five outbreaks of h7n9 influenza virus in humans in china since it emerged in 2013, infecting >1000 people. the h7n9 low pathogenic influenza virus was inserted into four amino acids in the ha protein cleavage site to mutate into the h7n9 highly pathogenic virus. this emerging virus caused 15 outbreaks in chickens from the end of 2016 to date. two h7n9 avian influenza virus (aiv) strains, a/chicken/guangdong/a46/2013 (lpaiv) and a/chicken/guangdong/q29/2017 (hpaiv), were selected to c ... | 2019 | 31717632 |
| evolution of h5-type avian influenza a virus towards mammalian tropism in egypt, 2014 to 2015. | highly pathogenic avian influenza viruses (hpaiv) of the h5-subtype have circulated continuously in egypt since 2006, resulting in numerous poultry outbreaks and considerable sporadic human infections. the extensive circulation and wide spread of these viruses in domestic poultry have resulted in various evolutionary changes with a dramatic impact on viral transmission ability to contact mammals including humans. the transmitted viruses are either (1) adapted well enough in their avian hosts to ... | 2019 | 31703251 |
| elucidating the interactions between influenza virus polymerase and host factor anp32a. | the avian-origin influenza a virus polymerase is restricted in human cells. this restriction has been associated with species differences in host factor anp32a. avian anp32a supports the activity of an avian-origin polymerase. however, the avian-origin polymerase is incompatible with human anp32a. avian anp32a proteins harbor an additional 33 amino acids compared to human anp32a proteins, which are crucial for their ability to support the avian-origin influenza virus polymerase. here, we elucida ... | 2020 | 31694956 |
| biosafety risk assessment for production of candidate vaccine viruses to protect humans from zoonotic highly pathogenic avian influenza viruses. | a major lesson learned from the public health response to the 2009 h1n1 pandemic was the need to shorten the vaccine delivery timeline to achieve the best pandemic mitigation results. a gap analysis of previous pre-pandemic vaccine development activities identified possible changes in the select agent exclusion process that would maintain safety and shorten the timeline to develop candidate vaccine viruses (cvvs) for use in pandemic vaccine manufacture. here, we review the biosafety characterist ... | 2020 | 31659871 |
| characterization of h7n9 avian influenza viruses isolated from duck meat products. | avian influenza h7n9 viruses have caused five epidemic waves of human infections since the first human cases were reported in 2013. in 2016, the initial low pathogenic avian influenza (lpai) h7n9 viruses became highly pathogenic, acquiring multi-basic amino acids at the haemagglutinin cleavage site. these highly pathogenic avian influenza (hpai) h7n9 viruses have been detected in poultry and humans in china, causing concerns of a serious threat to global public health. in japan, both hpai and lp ... | 2020 | 31650680 |
| detection error influences both temporal seroprevalence predictions and risk factors associations in wildlife disease models. | understanding the prevalence of pathogens in invasive species is essential to guide efforts to prevent transmission to agricultural animals, wildlife, and humans. pathogen prevalence can be difficult to estimate for wild species due to imperfect sampling and testing (pathogens may not be detected in infected individuals and erroneously detected in individuals that are not infected). the invasive wild pig (sus scrofa, also referred to as wild boar and feral swine) is one of the most widespread ho ... | 2019 | 31632645 |
| functional characterization of duck sting in ifn-β induction and anti-h9n2 avian influenza viruses infections. | the stimulator of interferon genes (sting) protein has been shown to play a pivotal role in response to both cytosolic rna and dsdna to elicit interferon (ifn) production in mammals. however, the role of duck sting (dusting) in antiviral innate immunity, especially in anti-rna virus infection, has yet to be elucidated. in this study, the function of dusting in ifn induction and its role in anti-rna virus infections were studied. dusting was amplified via reverse transcription-polymerase chain re ... | 2019 | 31620135 |
| serological survey of influenza a virus infection in japanese wild boars (sus scrofa leucomystax). | we conducted a serological survey to detect antibodies against influenza a virus (iav) in japanese wild boars in kagoshima prefecture, japan, between 2014 and 2017. seroprevalence against a pandemic-like swine h1n1 (h1n1pdm) virus was identified in 27.1% of specimens, and 1.7% were positive for both swine h1n2 and h3n2 viruses, indicating that wild boars could play an important role in the dynamics of h1n1pdm viral dispersion in the wild. the high frequency of positive results for sera against t ... | 2019 | 31595535 |
| influenza a(h5n1) virus subunit vaccine administered with capnp adjuvant induce high virus neutralization antibody titers in mice. | the highly pathogenic avian influenza h5n1 virus continues to spread globally in domestic poultry with sporadic transmission to humans. the possibility for its rapid transmission to humans raised global fears for the virus to gain capacity for human-to-human transmission to start a future pandemic. through direct contact with infected poultry, it caused the largest number of reported cases of severe disease and death in humans of any avian influenza strains. for pandemic preparedness, use of saf ... | 2019 | 31591662 |
| transcriptional and pathological host responses to coinfection with virulent or attenuated mycoplasma gallisepticum and low-pathogenic avian influenza a virus in chickens. | the avian pathogen mycoplasma gallisepticum, the etiological agent of chronic respiratory disease in chickens, exhibits enhanced pathogenesis in the presence of a copathogen such as low-pathogenic avian influenza virus (lpaiv). to further investigate the intricacies of this copathogenesis, chickens were monoinfected or coinfected with either virulent m. gallisepticum strain rlow or lpaiv h3n8 (a/duck/ukraine/1963), with assessment of tracheal histopathology, pathogen load, and transcriptomic hos ... | 2019 | 31591166 |
| organ-specific small non-coding rna responses in domestic (sudani) ducks experimentally infected with highly pathogenic avian influenza virus (h5n1). | the duck represents an important reservoir of influenza viruses for transmission to other avian and mammalian hosts, including humans. the increased pathogenicity of the recently emerging clades of highly pathogenic avian influenza (hpai) viruses of the h5n1 subtype in ducks features systemic viral spread and organ-to-organ variation in viral transcription and tissue damage. we previously reported that experimental infection of sudani ducks (cairina moschata) with an egyptian hpai (h5n1) virus ( ... | 2020 | 31538530 |
| h3n2 avian influenza viruses detected in live poultry markets in china bind to human-type receptors and transmit in guinea pigs and ferrets. | the h3n2 influenza viruses became widespread in humans during the 1968 h3n2 pandemic and have been a major cause of influenza epidemics ever since. different lineages of h3n2 influenza viruses are also commonly found in animals. if a different lineage of h3n2 virus jumps to humans, a human influenza pandemic could occur with devastating consequences. here, we studied the genetics, receptor-binding properties, and replication and transmission in mammals of 15 h3n2 avian influenza viruses detected ... | 2019 | 31495283 |
| antigenic pressure on h3n2 influenza virus drift strains imposes constraints on binding to sialylated receptors but not phosphorylated glycans. | h3n2 strains of influenza a virus emerged in humans in 1968 and have continued to circulate, evolving in response to human immune pressure. during this process of "antigenic drift," viruses have progressively lost the ability to agglutinate erythrocytes of various species and to replicate efficiently under the established conditions for amplifying clinical isolates and generating vaccine candidates. we have determined the glycome profiles of chicken and guinea pig erythrocytes to gain insights i ... | 2019 | 31484755 |
| a study of the relationship between human infection with avian influenza a (h5n6) and environmental avian influenza viruses in fujian, china. | avian influenza a (h5n6) virus poses a great threat to the human health since it is capable to cross the species barrier and infect humans. although human infections are believed to largely originate from poultry contaminations, the transmissibility is unclear and only limited information was available on poultry environment contaminations, especially in fujian province. | 2019 | 31477028 |
| genetic characteristics and polymorphisms in the chicken interferon-induced transmembrane protein (ifitm3) gene. | the interferon-induced transmembrane protein 3 (ifitm3) gene is classified as a small interferon-stimulated gene and is associated with a broad spectrum of antiviral functions against several fatal enveloped viruses, including influenza a viruses (iavs). the rs12252 single nucleotide polymorphism (snp) of the ifitm3 gene in humans was associated with susceptibility to h1n1 influenza in a 2009 pandemic. in addition, overexpression of the ifitm3 protein potently inhibits the highly pathogenic avia ... | 2019 | 31410631 |
| isolation of highly pathogenic h5n6 avian influenza virus in southern vietnam with genetic similarity to those infecting humans in china. | since 2013, h5n6 highly pathogenic avian influenza viruses (hpaivs) have been responsible for outbreaks in poultry and wild birds around asia. h5n6 hpaiv is also a public concern due to sporadic human infections being reported in china. in the current study, we isolated an h5n6 hpaiv strain (a/muscovy duck/long an/ai470/2018; ai470) from an outbreak at a muscovy duck farm in long an province in southern vietnam in july 2018 and genetically characterized it. basic local alignment search tool (bla ... | 2019 | 31309743 |
| characterization of swine-origin h1n1 canine influenza viruses. | host switch events of influenza a viruses (iavs) continuously pose a zoonotic threat to humans. in 2013, swine-origin h1n1 iavs emerged in dogs soon after they were detected in swine in the guangxi province of china. this host switch was followed by multiple reassortment events between these h1n1 and previously circulating h3n2 canine iavs (iavs-c) in dogs. to evaluate the phenotype of these newly identified viruses, we characterized three swine-origin h1n1 iavs-c and one reassortant h1n1 iav-c. ... | 2019 | 31287780 |
| individual-level antibody dynamics reveal potential drivers of influenza a seasonality in wild pig populations. | swine are important in the ecology of influenza a virus (iav) globally. understanding the ecological role of wild pigs in iav ecology has been limited because surveillance in wild pigs is often for antibodies (serosurveillance) rather than iavs, as in humans and domestic swine. as iav antibodies can persist long after an infection, serosurveillance data are not necessarily indicative of current infection risk. however, antibody responses to iav infections cause a predictable antibody response, t ... | 2019 | 31251341 |
| phylogenetic analysis of ha and na genes of influenza h1n1 viruses from 1918 to 2017. | the 1918 "spanish" pandemic is the earliest known influenza h1n1 virus. since then h1n1 viruses circulated between humans and animals continuously. with the increased amount of samples of h1n1 viruses and technology development, researchers have been studying how the viruses evolved. here, we analyzed ha and na genes of h1n1 viruses from three aspects: host distribution, geographical distribution and phylogenetic analysis. the data showed hosts were predominantly human, swine and poultry, and ot ... | 2019 | 31230448 |
| are microneutralization and hemagglutination inhibition assays comparable? serological results from influenza experimentally infected mallard ducks. | the hemagglutination inhibition (hi) assay is commonly used to assess the humoral immune response against influenza a viruses (iav). however, the microneutralization (mn) assay has been reported to have higher sensitivity when testing sera from humans and other species. our objective was to determine the agreement between mn and hi assays and compare the proportion of positive samples detected by both methods in sera of mallards primary infected with the a/mallard/mn/sg-000169/ 2007 (h3n8) virus ... | 2019 | 31131570 |
| comparative micro-epidemiology of pathogenic avian influenza virus outbreaks in a wild bird population. | understanding the epidemiological dynamics of highly pathogenic avian influenza virus (hpaiv) in wild birds is crucial for guiding effective surveillance and control measures. the spread of h5 hpaiv has been well characterized over large geographical and temporal scales. however, information about the detailed dynamics and demographics of individual outbreaks in wild birds is rare and important epidemiological parameters remain unknown. we present data from a wild population of long-lived birds ... | 2019 | 31056057 |
| semi-perfusion cultures of suspension mdck cells enable high cell concentrations and efficient influenza a virus production. | control and prevention of rapid influenza spread among humans depend on the availability of efficient and safe seasonal and pandemic vaccines, made primarily from inactivated influenza virus particles. current influenza virus production processes rely heavily on embryonated chicken eggs or on cell culture as substrate for virus propagation. today's efforts towards process intensification in animal cell culture could innovate viral vaccine manufacturing using high-yield suspension cells in high c ... | 2019 | 31047676 |
| influenza a viruses in birds and humans: prevalence, molecular characterization, zoonotic significance and risk factors' assessment in poultry farms. | this study aimed to investigate the prevalence of influenza a viruses in birds and humans residing in the same localities of sharkia province, egypt and the risk factors' assessment in poultry farms. a total of 100 birds comprised of 50 chickens, 25 ducks and 25 wild egrets were sampled. swab samples were collected from 65 people (50 poultry farm workers and 15 hospitalized patients). all samples were screened for the presence of influenza a viruses using isolation and molecular assays. avian in ... | 2019 | 30961818 |
| h9n2 viruses isolated from mammals replicated in mice at higher levels than avian-origin viruses. | h9n2 subtype influenza a virus (iav) has more than 20 genotypes that are able to cross species barriers and expand from birds to mammals and humans. to better understand the impact of different h9n2 genotypes and their characteristics, five h9n2 viruses from different hosts including chickens, geese, pigs, mink, and humans representing the b69 88(gs/14, ck/15, and mi/14), b35 (sw/08) and g9 genotypes (hu/04) were infected in chicken and mice. in mice, mammal-origin viruses replicated at higher l ... | 2019 | 30915048 |
| a computationally designed h5 antigen shows immunological breadth of coverage and protects against drifting avian strains. | since the first identification of the h5n1 goose/guangdong lineage in 1996, this highly pathogenic avian influenza virus has spread worldwide, becoming endemic in domestic poultry. sporadic transmission to humans has raised concerns of a potential pandemic and underscores the need for a broad cross-protective influenza vaccine. here, we tested our previously described methodology, termed computationally optimized broadly reactive antigen (cobra), to generate a novel hemagglutinin (ha) gene, term ... | 2019 | 30905528 |
| diverse biological characteristics and varied virulence of h7n9 from wave 5. | there was a substantial increase with infections of h7n9 avian influenza virus (aiv) in humans during wave 5 (2016-2017). to investigate whether h7n9 had become more infectious/transmissible and pathogenic overall, we characterized the receptor binding and experimentally infected ferrets with highly pathogenic (hp)- and low pathogenic (lp)-h7n9 isolates selected from wave 5, and compared their pathogenicity and transmissibility with a wave 1 isolate from 2013. studies show that a/anhui/1/2013 (l ... | 2019 | 30866763 |
| comparative health assessments of alaskan ice seals. | bearded (erignathus barbatus), ringed (pusa hispida), spotted (phoca largha), and ribbon (histriophoca fasciata) seals rely on seasonal sea-ice in arctic and sub-arctic regions. many aspects of the biology and physiology of these seals are poorly known, and species-typical health parameters are not available for all species. such information has proven difficult to obtain due to the challenges of studying arctic seals in the wild and their minimal historic representation in aquaria. here, we com ... | 2019 | 30792982 |
| global transcriptome analysis of h5n1 influenza virus-infected human cells. | influenza a virus (iav) belongs to the orthomyxoviridae family. iav causes a highly contagious respiratory disease in humans that exacts severe economic losses globally. the virus uses strategies developed to exploit and subvert cellular proteins and pathways to increase its own replication and to inhibit antiviral immune response. | 2019 | 30774581 |
| characterization of mouse monoclonal antibodies against the ha of a(h7n9) influenza virus. | many cases of human infection with the h7n9 virus have been detected in china since 2013. h7n9 viruses are maintained in chickens and are transmitted to humans at live bird markets. during circulation in birds, h7n9 viruses have accumulated amino acid substitutions in their hemagglutinin (ha), which resulted in an antigenically change in the recent h7n9 viruses. here, we characterized 46 mouse monoclonal antibodies against the ha of the prototype strain. 16 h7-ha-specific monoclonal antibodies ( ... | 2019 | 30754701 |
| analysis of the efficacy of an adjuvant-based inactivated pandemic h5n1 influenza virus vaccine. | this paper describes a preclinical study analyzing the immunogenicity and protective efficacy of kazfluvac®, an adjuvant-based inactivated pandemic influenza a/h5n1 virus vaccine. in this study, laboratory animals (ferrets and mice) were vaccinated by the intramuscular or intraperitoneal route at an interval of 14 days with two doses of the vaccine containing different concentrations of influenza virus hemagglutinin (ha) protein. ha protein without adjuvant (aluminum hydroxide and merthiolate) w ... | 2019 | 30740636 |
| serological evidence of hepatitis e virus and influenza a virus infection in farmed wild boars in china. | hepatitis e virus (hev) and influenza a virus (iav) are two important pathogens which can infect humans and various animals causing public health problems. in this study, the seroprevalence and risk factors associated with hev and iav infection in farmed wild boars were investigated in china. a total of 758 serum samples were collected from farmed wild boars between 2015 and 2016, and antibodies against hev and iav were examined by enzyme-linked immunosorbent assay (elisa) using commercially ava ... | 2019 | 30738024 |
| identification and analysis of long non-coding rnas in response to h5n1 influenza viruses in duck (anas platyrhynchos). | long non-coding rnas (lncrnas) are important component of mammalian genomes, where their numbers are even larger than that of protein-coding genes. for example, human (homo sapiens) (96,308 vs. 20,376) and mouse (mus musculus) (87,774 vs. 22,630) have more lncrna genes than protein-coding genes in the noncodev5 database. recently, mammalian lncrnas were reported to play critical roles in immune response to influenza a virus infections. such observation inspired us to identify lncrnas related to ... | 2019 | 30634898 |
| genetic characterization of an h13n2 low pathogenic avian influenza virus isolated from gulls in china. | low pathogenic avian influenza viruses circulate in wild birds but are occasionally transmitted to other species, including poultry, mammals and humans. to date, infections with low pathogenic avian influenza viruses of ha subtype 6, ha subtype 7, ha subtype 9 and ha subtype 10 among humans have been reported. however, the epidemiology, genetics and ecology of low pathogenic avian influenza viruses have not been fully understood thus far. therefore, persistent surveillance of low pathogenic avia ... | 2019 | 30578616 |
| avian influenza overview august - november 2018. | between 16 august and 15 november 2018, 14 highly pathogenic avian influenza (hpai) a(h5n8) outbreaks in poultry establishments in bulgaria and seven hpai a(h5n6) outbreaks, one in captive birds in germany and six in wild birds in denmark and the netherlands were reported in the european union (eu). no human infection due to hpai a(h5n8) and a(h5n6) viruses have been reported in europe so far. seroconversion of people exposed during outbreaks in russia has been reported in one study. although th ... | 2018 | 32625795 |
| exposure of alaska brown bears (ursus arctos) to bacterial, viral, and parasitic agents varies spatiotemporally and may be influenced by age. | we collected blood and serum from 155 brown bears (ursus arctos) inhabiting five locations in alaska, us during 2013-16 and tested samples for evidence of prior exposure to a suite of bacterial, viral, and parasitic agents. antibody seroprevalence among alaska brown bears was estimated to be 15% for brucella spp., 10% for francisella tularensis, 7% for leptospira spp., 18% for canine adenovirus type 1 (cav-1), 5% for canine distemper virus (cdv), 5% for canine parvovirus, 5% for influenza a viru ... | 2019 | 30557123 |
| probable reverse zoonosis of influenza a(h1n1)pdm 09 in a striped skunk (mephitis mephitis). | striped skunks (skunks) are susceptible to respiratory infection by influenza a viruses (iav). as they are common synanthropes, maintenance of iav in skunks could provide a source of infection for humans. we previously studied the nasal turbinates, lungs and faeces of 50 free-ranging skunks for the presence of iav and identified two individuals with influenza a(h1n1)pdm09 infection during the 2009/2010 and 2013/2014 flu seasons. subsequent to publication of that study, ferrets were shown to pref ... | 2019 | 30552753 |
| pathogenicity of two novel human-origin h7n9 highly pathogenic avian influenza viruses in chickens and ducks. | human infection by low-pathogenic avian influenza viruses of the h7n9 subtype was first reported in march 2013 in china. subsequently, these viruses caused five outbreaks through september 2017. in the fifth outbreak, h7n9 virus possessing a multiple basic amino acid insertion in the cleavage site of hemagglutinin emerged and caused 4% of all human infections in that period. to date, h7n9 highly pathogenic avian influenza viruses (hpaivs) have been isolated from poultry, mostly chickens, as well ... | 2019 | 30539262 |
| epidemiological and molecular analysis of avian influenza a(h7n9) virus in shanghai, china, 2013-2017. | human infections with a novel avian influenza a virus (h7n9) were reported in shanghai municipality, china, at the beginning of 2013. high-pathogenic avian influenza (hpai) h7n9 virus emerged in late february 2017 along with existing low-pathogenic avian influenza (lpai) h7n9 virus, and this has the potential to develop into a pandemic that could be harmful to humans. | 2018 | 30538508 |
| biological characteristics and immunological properties in muscovy ducks of h5n6 virus-like particles composed of ha-tm/ha-tmh3 and m1. | highly pathogenic avian influenza viruses (hpaivs), including h5n6 strains, pose threats to the health of humans and poultry. waterfowl play a crucial role as a reservoir of hpaivs. since current influenza vaccines induce poor antibody titres in waterfowl, there is an urgent need to develop an efficient vaccine against h5n6 infection. in this study, we constructed two h5n6 virus-like particles (vlps) composed of matrix-1 (m1) and haemagglutinin of wildtype (ha-tm) or haemagglutinin with transmem ... | 2019 | 30404538 |
| mutation of influenza a virus pa-x decreases pathogenicity in chicken embryos and can increase the yield of reassortant candidate vaccine viruses. | the pa-x protein of influenza a virus has roles in host cell shutoff and viral pathogenesis. while most strains are predicted to encode pa-x, strain-dependent variations in activity have been noted. we found that pa-x protein from the a/pr/8/34 (pr8) strain had significantly lower repressive activity against cellular gene expression than pa-x proteins from the avian strains a/turkey/england/50-92/91 (h5n1) (t/e) and a/chicken/rostock/34 (h7n1). loss of normal pa-x expression, either by mutation ... | 2019 | 30381488 |
| the roles of migratory and resident birds in local avian influenza infection dynamics. | migratory birds are an increasing focus of interest when it comes to infection dynamics and the spread of avian influenza viruses (aiv). however, we lack detailed understanding migratory birds' contribution to local aiv prevalence levels and their downstream socio-economic costs and threats.to explain the potential differential roles of migratory and resident birds in local aiv infection dynamics, we used a susceptible-infectious-recovered (sir) model. we investigated five (mutually non- exclusi ... | 2018 | 30337766 |
| genetic characterization of the first detected human case of avian influenza a (h5n6) in anhui province, east china. | we compared complete genome sequences of two strains of an avian influenza a (h5n6) virus isolated from a patient in anhui province with those of other strains from genbank and global initiative on sharing all influenza data (gisaid). the ha gene of the isolated virus shared homology with that of a/chicken/zhejiang/727155/2014 (h5n6) at the level of similarity of 98%. the six internal genes of the anhui strains were close to those of h9n2 viruses from zhejiang, shandong, and guangdong provinces, ... | 2018 | 30327485 |
| chickens expressing ifit5 ameliorate clinical outcome and pathology of highly pathogenic avian influenza and velogenic newcastle disease viruses. | innate antiviral immunity establishes first line of defense against invading pathogens through sensing their molecular structures such as viral rna. this antiviral potential of innate immunity is mainly attributed to a myriad of ifn-stimulated genes (isgs). amongst well-characterized isgs, we have previously shown that antiviral potential of chicken ifn-induced proteins with tetratricopeptides repeats 5 (chifit5) is determined by its interaction potential with 5'ppp containing viral rna. here, w ... | 2018 | 30271403 |
| bioaerosol sampling to detect avian influenza virus in hanoi's largest live poultry market. | newly emergent and virulent strains of h7n9 avian influenza virus are rapidly spreading in china and threaten to invade vietnam. we sought to introduce aerosol sampling for avian influenza viruses in vietnam. | 2019 | 30184114 |
| genetic characteristics of h9n2 avian influenza viruses isolated from free-range poultry in eastern china, in 2014-2015. | circulating h7n9 influenza viruses in live poultry markets continue to pose a threat to human health. free-range poultry, one of the sources for these markets, are common in china as well as in many developing countries. because the h9n2 virus could be a source of internal genes for the h7n9 virus, we conducted surveillance in free-range poultry and live poultry markets to study the evolution of h7n9 and h9n2 viruses in eastern china. we found 28 samples positive for the h9n2 virus (a rate of 3. ... | 2018 | 30169762 |
| evaluation of the potential defensive strategy against influenza a in cell line models. | background: influenza virus can cause both seasonal infections and unpredictable pandemics. rapidly evolving avian h5n1 and h7n9 viruses have a potential pandemic threat for humans. since avian influenza can be transmitted by domestic birds, serving as a key link between wild birds and humans, an effective measure to control the influenza transmission would be eradication of the infection in poultry. it is known that the virus penetrates into the cell through binding with the terminal oligosacc ... | 2018 | 29946435 |
| avian influenza overview february - may 2018. | between 16 february and 15 may 2018, three highly pathogenic avian influenza (hpai) a(h5n6) and 11 hpai a(h5n8) outbreaks in poultry holdings, one hpai a(h5n6) and one hpai a(h5n8) outbreak in captive birds, and 55 hpai a(h5n6) wild bird events were reported in europe. there is no evidence to date that hpai a(h5n6) viruses circulating in europe are associated with clades infecting humans. fewer hpai wild bird cases have been detected than during the same period of previous year. most of mortalit ... | 2018 | 32625951 |
| the second-generation thiazolide haloxanide is a potent inhibitor of avian influenza virus replication. | the emergence of new avian influenza virus (aiv) strains able to infect humans represents a serious threat to global human health. in addition to surveillance and vaccine development, antiviral therapy remains crucial for aiv control; however, the increase in drug-resistant aiv strains underscores the need for novel approaches to anti-influenza chemotherapy. we have previously shown that the thiazolide anti-infective nitazoxanide (ntz) inhibits influenza a/puertorico/8/1934(h1n1) virus replicati ... | 2018 | 29908209 |
| mitigation strategies to reduce the generation and transmission of airborne highly pathogenic avian influenza virus particles during processing of infected poultry. | airborne transmission of h5n1 highly pathogenic avian influenza (hpai) viruses has occurred among poultry and from poultry to humans during home or live-poultry market slaughter of infected poultry, and such transmission has been experimentally reproduced. in this study, we investigated simple, practical changes in the processing of h5n1 virus-infected chickens to reduce infectious airborne particles and their transmission. our findings suggest that containing the birds during the killing and bl ... | 2018 | 29891217 |
| h9n2 avian influenza virus retained low pathogenicity after serial passage in chickens. | the h9n2 strains of avian influenza viruses (aivs) circulate worldwide in poultry and cause sporadic infection in humans. to better understand the evolution of these viruses while circulating in poultry, an h9n2 chicken isolate was passaged 19 times in chickens via aerosol inoculation. whole-genome sequencing showed that the viruses from the initial stock and those after the 8th and 19th passages (p0, p8, and p19) all had the same monobasic cleavage site in the hemagglutinin (ha), typical for vi ... | 2018 | 29755193 |
| the fifth influenza a(h7n9) epidemic: a family cluster of infection in suzhou city of china, 2016. | influenza a(h7n9) virus is known for its high pathogenicity in human. a family cluster of influenza a(h7n9) virus infection was identified in suzhou, china. this study aimed to investigate the possibility of human-to-human transmission of the virus and examine the virologic features of this family cluster. | 2018 | 29738825 |
| potential biological and climatic factors that influence the incidence and persistence of highly pathogenic h5n1 avian influenza virus in egypt. | highly pathogenic h5n1 avian influenza virus (a/h5n1) of clade 2.2.1 is endemic in poultry in egypt where the highest number of human infections worldwide was reported. during the last 12 years the egyptian a/h5n1 evolved into several genotypes. in 2007-2014 vaccinated poultry suffered from antigenic drift variants of clade 2.2.1.1 and in 2014/2015 an unprecedented upsurge of a/h5n1 clade 2.2.1.2 occurred in poultry and humans. factors contributing to the endemicity or re-emergence of a/h5n1 in ... | 2018 | 29636730 |
| functional growth inhibition of influenza a and b viruses by liquid and powder components of leaves from the subtropical plant melia azedarach l. | we evaluated the anti-influenza-virus effects of melia components and discuss the utility of these components. the effects of leaf components of melia azedarach l. on viruses were examined, and plaque inhibition tests were performed. the in vivo efficacy of m. azedarach l. was tested in a mouse model. leaf components of melia azedarach l. markedly inhibited the growth of various influenza viruses. in an initial screening, multiplication and haemagglutination (ha) activities of h1n1, h3n2, h5, an ... | 2018 | 29633076 |
| ns segment of a 1918 influenza a virus-descendent enhances replication of h1n1pdm09 and virus-induced cellular immune response in mammalian and avian systems. | the 2009 pandemic influenza a virus (iav) h1n1 strain (h1n1pdm09) has widely spread and is circulating in humans and swine together with other human and avian iavs. this fact raises the concern that reassortment between h1n1pdm09 and co-circulating viruses might lead to an increase of h1n1pdm09 pathogenicity in different susceptible host species. herein, we explored the potential of different ns segments to enhance the replication dynamics, pathogenicity and host range of h1n1pdm09 strain a/gies ... | 2018 | 29623073 |
| surveillance in 2013 of avian influenza virus from live-bird markets in bangkok, thailand. | live-bird markets have been implicated in transmission of avian influenzaviruses, most recently of influenza a (h7n9) in china. low pathogenic avianinfluenza (lpai) viruses, such as h7n9, cause asymptomatic infections in poultry,and active surveillance is required to detect infection and to prevent transmissionto humans. although limited numbers of live birds for consumption are sold inbangkok live bird markets (lbm), transmission of h7n9 in nearby china hasprompted a program of active surveilla ... | 2017 | 29644818 |
| influenza virus: a brief overview. | influenza is a major public health concern, infecting 5-15% of the global population annually. influenza virus belongs to family orthomyxoviridae, and has three types a, b and c. infection by influenza virus a is most common and severe, generally found in humans. it spreads rapidly and affects human population across large geographical region within short period of time with varying degree of pathology from mild to severe. wild aquatic birds and other animal species like birds, pigs, ferret, hor ... | 2012 | 32288055 |
| avian influenza, migratory birds and emerging zoonoses: unusual viral rna, enteropathogens and cryptosporidium in poultry litter. | the last decade has witnessed the emergence of several new viral infectious agents, most notably avian influenza h5n1, sars and west nile virus. the emergence of these agents is heavily associated with zonotic animal hosts, as well as migratory pathways of infected bird vectors. the environmental survival and persistence of nucleic acid associated with these viral agents may be important for both the detection as well as the occurrence of related diseases. our hypothesis suggests that nucleic ac ... | 2009 | 32362937 |
| modeling the spread of bird flu and predicting outbreak diversity. | avian influenza, commonly known as bird flu, is an epidemic caused by h5n1 virus that primarily affects birds like chickens, wild water birds, etc. on rare occasions, these can infect other species including pigs and humans. in the span of less than a year, the lethal strain of bird flu is spreading very fast across the globe mainly in south east asia, parts of central asia, africa and europe. in order to study the patterns of spread of epidemic, we made an investigation of outbreaks of the epid ... | 2008 | 32288641 |
| serosurvey of coyotes (canis latrans), foxes (vulpes vulpes, urocyon cinereoargenteus), and raccoons (procyon lotor) for exposure to influenza a viruses in the usa. | we tested coyote (canis latrans), fox (urocyon cinereoargenteus, vulpes vulpes), and raccoon (procyon lotor) sera for influenza a virus exposure. we found 2/139 samples (1 coyote, 1 raccoon) had iav antibodies and hemagglutination inhibition assays revealed the antibodies to the 2009/2010 h1n1 human pandemic virus or to the 2007 human seasonal h1n1 virus. | 2020 | 32320339 |
| influenza a(h1n1)pdm09 virus infection in a captive giant panda, hong kong. | we report influenza a(h1n1)pdm09 virus infection in a captive giant panda in hong kong. the viral load peaked on day 1 and became undetectable on day 5, and an antibody response developed. genome analysis showed 99.3%-99.9% nucleotide identity between the virus and influenza a(h1n1)pdm09 virus circulating in hong kong. | 2019 | 31742520 |
| a multi-hemagglutinin-based enzyme-linked immunosorbent assay to serologically detect influenza a virus infection in animals. | mammals can play a role as an intermediate host in the emergence of mammalian-adapted reassortants or mutants of avian influenza a viruses, with pandemic potential. therefore, detecting viral infection in animals followed by assessment of the hemagglutinin (ha) subtype of the agent is an indispensable process for risk assessment in pandemic preparedness. in this study, we tested the potential of an enzyme-linked immunosorbent assay as a rapid diagnosis method, using a panel of ha subtype antigen ... | 2019 | 31336638 |
| first detection of influenza a virus genes from wild raccoons in japan. | serological surveys have shown that wild raccoons are exposed to influenza a viruses (iavs); however, no genetic evidence for this iav infection has been found. in the present study, we first detected iav genes in wild raccoons captured during periods other than the wintering season of migratory waterfowl and epidemic season of influenza in japan. viral matrix (m) and nucleoprotein (np) genes were detected by a conventional reverse transcription-polymerase chain reaction assay from three sucklin ... | 2018 | 29740778 |
| highly pathogenic avian influenza a(h5n6) in domestic cats, south korea. | in december 2016, highly pathogenic avian influenza (hpai) infection with systemic pathologic lesions was found in cats in south korea. genetic analyses indicated that the feline isolates were similar to hpai h5n6 viruses isolated in chicken farms nearby. this finding highlights the need for monitoring of domestic mammals during hpai outbreaks. | 2018 | 30457524 |
| serological evidence of influenza virus infection in captive wild felids, thailand. | influenza virus is known to affect wild felids. to explore the prevalence of influenza viruses in these animal species, 196 archival sera from 5 felid species including panthera tigris (n=147), prionailurus viverrinus (n=35), panthera leo (n=5), pardofelis temminckii (n=8) and neofelis nebulosa (n=1) collected between 2011 and 2015 in 10 provinces of thailand were determined for the presence of antibody to avian and human influenza viruses. blocking enzyme-linked immunosorbent (elisa) assay and ... | 2019 | 31341136 |
| clade 2.3.2.1 h5n1 avian influenza viruses circulate at the interface of migratory and domestic birds around qinghai lake in china. | during 2012-2015, six h5n1 avian influenza viruses were isolated from domestic birds and the environment around qinghai lake. phylogenetic analysis of ha genes revealed that a/chicken/gansu/xg2/2012 (ck/gs/xg2/12) belonged to clade 2.3.2.1a, while a/environment/qinghai/1/2013 (en/qh/1/13), a/chicken/qinghai/qh1/2015 (ck/qh/qh1/15), a/chicken/qinghai/qh2/2015 (ck/qh/qh2/15), a/chicken/qinghai/qh3/2015 (ck/qh/qh3/15), and a/goose/qinghai/qh6/2015 (gs/qh/qh6/15) belonged to clade 2.3.2.1c. further ... | 2019 | 31383307 |
| serological surveillance of avian influenza virus and canine distemper virus in captive siberian tigers in northeastern china. | in order to understand infection of avian influenza a virus (aiv) and canine distemper virus (cdv) in the siberian tiger in northeast china, 75 siberian tiger serum samples from three cap- tive facilities in northeastern china were collected. aiv and cdv antibody surveillance was test- ed by using hemagglutination inhibition and serum neutralization methods. the results showed that the seroprevalence of h5 aiv, h9 aiv and cdv was respectively 9.33% (7/75), 61.33% (46/75) and 16% (12/75). in the ... | 2018 | 30468333 |
| highly pathogenic avian influenza a(h5n8) virus in gray seals, baltic sea. | we detected a highly pathogenic avian influenza a(h5n8) virus in lung samples of 2 gray seals (halichoerus grypus) stranded on the baltic coast of poland in 2016 and 2017. this virus, clade 2.3.4.4 b, was closely related to avian h5n8 viruses circulating in europe at the time. | 2019 | 31742519 |
| a brief introduction to influenza a virus in marine mammals. | influenza a infection has been detected in marine mammals going back to 1975, with additional unconfirmed outbreaks as far back as 1931. over the past forty years, infectious virus has been recovered on ten separate occasions from both pinnipeds (harbor seal, elephant seal, and caspian seal) and cetaceans (striped whale and pilot whale). recovered viruses have spanned a range of subtypes (h1, h3, h4, h7, h10, and h13) and, in all but h1n1, show strong evidence for deriving directly from avian so ... | 2020 | 32170708 |
| anti-influenza a viral butenolide from streptomyces sp. smu03 inhabiting the intestine of elephas maximus. | actinobacteria are a phylum of bacteria known for their potential in producing structurally diversified natural products that are always associated with a broad range of biological activities. in this paper, using an h5n1 pseudo-typed virus drug screening system combined with a bioassay guided purification approach, an antiviral butanolide (1) was identified from the culture broth of streptomyces sp. smu03, a bacterium isolated from the feces of elephas maximus in yunnan province, china. this co ... | 2018 | 29976861 |
| survey of serum amyloid a and bacterial and viral frequency using qpcr levels in recently captured feral donkeys from death valley national park (california). | feral donkey removal from state land has raised concerns in terms of disease transmission between equine species. disease outbreaks may occur as a result of the relocation of animals to new environments. virus and bacteria dna load and serum amyloid a derived from the pathogenic processes that they involve were measured in recently captured donkeys. blood and nasal swabs were collected from 85 donkeys (death valley national park, shoshone, california); 24 were retested after 30/60 days in the sc ... | 2020 | 32585994 |
| validation of two multiplex real-time pcr assays based on single nucleotide polymorphisms of the ha1 gene of equine influenza a virus in order to differentiate between clade 1 and clade 2 florida sublineage isolates. | we validated 2 multiplex real-time pcr (rtpcr) assays based on single nucleotide polymorphisms (snps) of the hemagglutinin-1 ( ha1) gene of h3n8 equine influenza a virus (eiv) to determine clade affiliation of prototype and field isolates. initial validation of the 2 multiplex rtpcr assays (snp1 and snp2) was performed using nucleic acid from 14 eiv florida sublineage clade 1 and 2 prototype strains. we included in our study previously banked eiv rtpcr-positive nasal secretions from 341 horses c ... | 2019 | 30803412 |
| sigma animal disease data model: a comprehensive approach for the collection of standardised data on animal diseases. | the european commission is routinely asking efsa for scientific and technical support in the epidemiological analysis of animal disease outbreaks (i.e. african swine fever, lumpy skin disease and avian influenza) and to report or assess surveillance data (i.e. echinococcus multilocularis and avian influenza). for this purpose, efsa has over the last years carried out several data collections and gathered specific information on outbreaks, surveillance activities and concerned animal populations ... | 2019 | 32626101 |
| serologic and virologic evidence of influenza a viruses in wild boars ( sus scrofa) from two different locations in italy. | swine influenza viruses (sivs) have been repeatedly demonstrated to circulate in wild boar ( sus scrofa) populations, whereas no evidence of exposure to avian influenza viruses (aivs) has been described in wild boar. to better understand how different environments may influence the ecology of influenza a viruses (iavs) in wild suid populations, we examined biologic samples of wild boars from two study areas represented by an upland (ul) and a wetland (wl) in northern and central italy, respectiv ... | 2019 | 30235085 |
| serological survey of influenza a viruses in domestic and wild suidae in corsica (france), a mediterranean island environment. | corsica is a mountainous french island in the north-western mediterranean sea. it is a rural area, where pig farming is a major economic activity. although no acute respiratory outbreaks due to swine influenza a viruses (swiavs) have ever been reported in this free-ranging pig breeding system, influenza a viruses (iavs) could be circulating within this pig population. a serological study was conducted as a first approach to domestic pigs and wild boars. serum samples from 543 pigs raised on 91 d ... | 2018 | 30086855 |
| investigation of a cluster of severe respiratory disease referred from uganda to kenya, february 2017. | on february 22, 2017, hospital x-kampala and us cdc-kenya reported to the uganda ministry of health a respiratory illness in a 46-year-old expatriate of company a. the patient, mr. a, was evacuated from uganda to kenya and died. he had recently been exposed to dromedary camels (mers-cov) and wild birds with influenza a (h5n6). we investigated the cause of illness, transmission, and recommended control. we defined a suspected case of severe acute respiratory illness (sari) as acute onset of fever ... | 2020 | 32324075 |
| influenza a virus infections in dromedary camels, nigeria and ethiopia, 2015-2017. | we examined nasal swabs and serum samples acquired from dromedary camels in nigeria and ethiopia during 2015-2017 for evidence of influenza virus infection. we detected antibodies against influenza a(h1n1) and a(h3n2) viruses and isolated an influenza a(h1n1)pdm09-like virus from a camel in nigeria. influenza surveillance in dromedary camels is needed. | 2020 | 31855544 |
| molecular evidence of influenza a virus circulation in african dromedary camels imported to saudi arabia, 2017-2018. | little is known about influenza a viruses in dromedaries. here, we detected influenza a viral rna in 11 specimens (1.7 %) out of 665 nasal swabs collected from dromedaries between 2017 and 2018 in saudi arabia. positive samples were detected only in imported camels from sudan and djibouti but not local ones. partial genome sequencing indicates a close relationship to 2009-2019 human/swine influenza a h1n1 isolates from different countries, suggesting possible interspecies transmission. taken tog ... | 2019 | 31660338 |
| three new compounds from the actinomycete actinocorallia aurantiaca. | aurantiadioic acids a (1) and b (2), two new furan-containing polyketides, and aurantoic acid a (3), a new natural product, were isolated from the liquid fermentation of the sika deer dung-derived actinomycete actinocorallia aurantiaca. the structures of the new compounds were established by extensive spectroscopic methods, including 1d & 2d nmr, hresims spectroscopic analysis. the absolute configuration of 3 was assigned by comparison of the specific optical rotations with the reported derivati ... | 2019 | 31529277 |
| survey of arctic alaskan wildlife for influenza a antibodies: limited evidence for exposure of mammals. | influenza a viruses (iavs) are maintained in wild waterbirds and have the potential to infect a broad range of species, including wild mammals. the arctic coastal plain of alaska supports a diverse suite of species, including waterfowl that are common hosts of iavs. mammals co-occur with geese and other migratory waterbirds during the summer breeding season, providing a plausible mechanism for interclass transmission of iavs. to estimate iav seroprevalence and identify the subtypes to which gees ... | 2019 | 30289331 |
| 'big data' in animal health research - opportunities and challenges. | automated systems for high-input data collection and data storage have led to exponential growth in the availability of information. such datasets and the tools applied to them have been referred to as 'big data'. starting with a systematic review of the terms 'informatics, bioinformatics and big data' in animal health this special issue of ahrr illustrates some big-data applications with papers on how the use of various omics methods may be used to facilitate the development of improved diagnos ... | 2020 | 32684189 |
| influenza d virus infection in feral swine populations, united states. | influenza d virus (idv) has been identified in domestic cattle, swine, camelid, and small ruminant populations across north america, europe, asia, south america, and africa. our study investigated seroprevalence and transmissibility of idv in feral swine. during 2012-2013, we evaluated feral swine populations in 4 us states; of 256 swine tested, 57 (19.1%) were idv seropositive. among 96 archived influenza a virus-seropositive feral swine samples collected from 16 us states during 2010-2013, 41 ... | 2018 | 29774857 |
| generation of h7n9-specific human polyclonal antibodies from a transchromosomic goat (caprine) system. | to address the unmet needs for human polyclonal antibodies both as therapeutics and diagnostic reagents, building upon our previously established transchromosomic (tc) cattle platform, we report herein the development of a tc goat system expressing human polyclonal antibodies in their sera. in the tc goat system, a human artificial chromosome (hac) comprising the entire human immunoglobulin (ig) gene repertoire in the germline configuration was introduced into the genetic makeup of the domestic ... | 2019 | 30675003 |
| orbitally shaken single-use bioreactor for animal cell cultivation: fed-batch and perfusion mode. | increasing the cultivation volume from small to large scale can be a rather complex and challenging process when the method of aeration and mixing is different between scales. orbitally shaken bioreactors (osbs) utilize the same hydrodynamic principles that define the success of smaller-scale cultures, which are developed on an orbitally shaken platform, and can simplify scale-up. here we describe the basic working principles of scale-up in terms of the volumetric oxygen transfer coefficient (kl ... | 2020 | 31858465 |
| recombinant hemagglutinin produced from chinese hamster ovary (cho) stable cell clones and a pelc/cpg combination adjuvant for h7n9 subunit vaccine development. | the novel h7n9 avian influenza a virus has caused human infections in china since 2013; some isolates from the fifth wave of infections have emerged as highly pathogenic avian influenza viruses. recombinant hemagglutinin proteins of h7n9 viruses can be rapidly and efficiently produced with low-level biocontainment facilities. in this study, recombinant h7 antigen was obtained from engineered stable clones of chinese hamster ovary (cho) cells for subsequent large-scale production. the stable cho ... | 2019 | 31383491 |
| targeting of influenza viral epitopes to antigen-presenting cells by genetically engineered chimeric molecules in a humanized nod scid gamma transfer model. | antiviral dna vaccines are a novel strategy in the vaccine development field, which basically consists of the administration of expression vectors coding viral antigen sequences into the host's cells. targeting of conserved viral epitopes by antibody fragments specific to activating cell surface co-receptor molecules on antigen-presenting cells could be an alternative approach for inducing protective immunity. it has been shown that fcγri on human monocytes enhances antigen presentation in vivo. ... | 2018 | 30191743 |
| the development and study of recombinant immunoglobulin a to hemagglutinins of the influenza virus. | we obtained recombinant variants of human antibody fi6 broadly specific to hemagglutinins of the influenza a virus. on the basis of a bi-promoter (cmv, hef1-htlv) vector, we developed genetic constructs for the expression of the heavy and light chains of the immunoglobulins of iga1-, iga2m1-, and igg-isotypes. following transfection and selection, stable chinese hamster ovary (cho) cell lines were produced. the antibodies of iga1-, iga2m1-, and igg-isotypes were purified from culture media. we p ... | 2020 | 30116613 |
| glycan-masking hemagglutinin antigens from stable cho cell clones for h5n1 avian influenza vaccine development. | refocusing of b-cell responses can be achieved by preserving the overall fold of the antigen structure but selectively mutating the undesired antigenic sites with additional n-linked glycosylation motifs for glycan masking the vaccine antigen. we previously reported that glycan-masking recombinant h5 hemagglutinin (rh5ha) antigens on residues 83, 127, and 138 (g127 + g138 or g83 + g127 + 138 rh5ha) elicited broader neutralizing antibodies and protection against heterologous clades/subclades of h ... | 2019 | 30080931 |
| experimental infections of norway rats with avian-derived low-pathogenic influenza a viruses. | | 2019 | 30976905 |
| wild bird-origin h5n6 avian influenza virus is transmissible in guinea pigs. | | 2020 | 32145213 |
| adaptive amino acid substitutions enable transmission of an h9n2 avian influenza virus in guinea pigs. | h9n2 is the most prevalent low pathogenic avian influenza virus (lpaiv) in domestic poultry in the world. two distinct h9n2 poultry lineages, g1-like (a/quail/hong kong/g1/97) and y280-like (a/duck/hong kong/y280/1997) viruses, are usually associated with binding affinity for both α 2,3 and α 2,6 sialic acid receptors (avian and human receptors), raising concern whether these viruses possess pandemic potential. to explore the impact of mouse adaptation on the transmissibility of a y280-like viru ... | 2019 | 31875046 |
| murine model for the study of influenza d virus. | a novel genus within the orthomyxoviridae family was identified in the united states and named influenza d virus (idv). bovines have been proposed to be the primary host, and three main viral lineages (d/ok-like, d/660-like, and d/japan-like) have been described. experimental infections had previously been performed in swine, ferrets, calves, and guinea pigs in order to study idv pathogenesis. we developed a murine experimental model to facilitate the study of idv pathogenesis and the immune res ... | 2020 | 31776281 |
| mutations in the h7 ha and pb1 genes of avian influenza a viruses increase viral pathogenicity and contact transmission in guinea pigs. | avian influenza a viruses (aiv) of the h7 subtype continue to evolve posing a pandemic threat. however, molecular markers of h7n7 aiv pathogenicity and transmission in mammals remain poorly understood. in this study, we performed a systematic in vitro and in vivo analysis by comparing an h7n7 highly pathogenic aiv and its ferret adapted variant. passaging an h7n7 aiv in ferrets led to six mutations in genes encoding the viral polymerase complex and the viral surface proteins. here, we show that ... | 2019 | 31503518 |
| incomplete influenza a virus genomes occur frequently but are readily complemented during localized viral spread. | segmentation of viral genomes into multiple rnas creates the potential for replication of incomplete viral genomes (ivgs). here we use a single-cell approach to quantify influenza a virus ivgs and examine their fitness implications. we find that each segment of influenza a/panama/2007/99 (h3n2) virus has a 58% probability of being replicated in a cell infected with a single virion. theoretical methods predict that ivgs carry high costs in a well-mixed system, as 3.6 virions are required for repl ... | 2019 | 31387995 |
| ifn-alpha1 antisense rna represses human influenza a virus growth in a guinea pig system. | we reported a natural antisense (as) long non-coding rna as an important modulator of interferon-alpha1 (ifna1) mrna levels. we showed that ifn-alpha1 as promotes ifna1 mrna stability by transient duplex formation and inhibition of mir-1270-induced mrna decay. here, we performed a proof-of-concept experiment to verify that the as-mrna regulatory axis exerts in vivo control of innate immunity. we established a model system for influenza virus infection using guinea pig, which encodes a functional ... | 2019 | 30844714 |
| h5n8 and h7n9 packaging signals constrain ha reassortment with a seasonal h3n2 influenza a virus. | influenza a virus (iav) has a segmented genome, which (i) allows for exchange of gene segments in coinfected cells, termed reassortment, and (ii) necessitates a selective packaging mechanism to ensure incorporation of a complete set of segments into virus particles. packaging signals serve as segment identifiers and enable segment-specific packaging. we have previously shown that packaging signals limit reassortment between heterologous iav strains in a segment-dependent manner. here, we evaluat ... | 2019 | 30760600 |
| a novel reassortant avian h7n6 influenza virus is transmissible in guinea pigs via respiratory droplets. | since 2013, h7n9 and h5n6 avian influenza viruses (aivs) have caused sporadic human infections and deaths and continued to circulate in the poultry industry. since 2014, h7n6 viruses which might be reassortants of h7n9 and h5n6 viruses, have been isolated in china. however, the biological properties of h7n6 viruses are unknown. here, we characterize the receptor binding preference, pathogenicity and transmissibility of a h7n6 virus a/chicken/hubei/00095/2017(h7n6) (abbreviated hb95), and a close ... | 2019 | 30723462 |
| the pa subunit of the influenza virus polymerase complex affects replication and airborne transmission of the h9n2 subtype avian influenza virus. | the polymerase acidic (pa) protein is the third subunit of the influenza a virus polymerase. in recent years, studies have shown that pa plays an important role in overcoming the host species barrier and host adaptation of the avian influenza virus (aiv). the objective of this study was to elucidate the role of the pa subunit on the replication and airborne transmission of the h9n2 subtype aiv. by reverse genetics, a reassortant rsd01-pa was derived from the h9n2 subtype aiv a/chicken/shandong/0 ... | 2019 | 30634394 |
| an infant mouse model of influenza virus transmission demonstrates the role of virus-specific shedding, humoral immunity, and sialidase expression by colonizing streptococcus pneumoniae. | the pandemic potential of influenza a viruses (iav) depends on the infectivity of the host, transmissibility of the virus, and susceptibility of the recipient. while virus traits supporting iav transmission have been studied in detail using ferret and guinea pig models, there is limited understanding of host traits determining transmissibility and susceptibility because current animal models of transmission are not sufficiently tractable. although mice remain the primary model to study iav immun ... | 2018 | 30563897 |