| avian and pandemic influenza: a biosocial approach. introduction. | the harvard university asian flus and avian influenza workshop, held in december 2006, introduced a biosocial approach to the preparation for and control of pandemics. a biosocial approach brings together the biological and social sciences to develop an integrative, collaborative response to the threat of pandemic influenza. the articles in this supplement provide a representative sampling of some of the ways in which the workshop worked toward this biosocial vision. these articles address the h ... | 2008 | 18269321 |
| preparing for avian influenza: lessons from the "swine flu affair". | as a low-likelihood, high-consequence event, the possibility of an influenza pandemic poses a difficult challenge to policymakers. drawing from the ill-fated swine influenza immunization program of 1976, this article outlines 7 lessons that apply to preparations for avian influenza: (1) beware of overconfidence in models drawn from meager evidence, (2) invest in a balanced portfolio of research and contemporary preparedness, (3) clarify operational responsibilities in the federal government, (4) ... | 2008 | 18269322 |
| swine influenza virus: zoonotic potential and vaccination strategies for the control of avian and swine influenzas. | influenza viruses are able to infect humans, swine, and avian species, and swine have long been considered a potential source of new influenza viruses that can infect humans. swine have receptors to which both avian and mammalian influenza viruses bind, which increases the potential for viruses to exchange genetic sequences and produce new reassortant viruses in swine. a number of genetically diverse viruses are circulating in swine herds throughout the world and are a major cause of concern to ... | 2008 | 18269323 |
| alveolar macrophages are indispensable for controlling influenza viruses in lungs of pigs. | alveolar macrophages constitutively reside in the respiratory tracts of pigs and humans. an in vivo role of alveolar macrophages in defending against influenza viruses in mice infected with a reassorted influenza virus, 1918 ha/na:tx/91, was reported, but there has been no report on an in vivo role of alveolar macrophages in a natural host such as a pig using currently circulating human influenza virus. here we show that in vivo depletion of alveolar macrophages in pigs by dichloromethylene diph ... | 2008 | 18287245 |
| spatial epidemiology of an h3n2 swine influenza outbreak. | the h3n2 swine influenza virus appeared for the 1st time in the province of manitoba during the fall of 2004. the purpose of this study was to characterize how swine influenza moved through the province in time and space, and to determine if there are any significant patterns associated with this movement. herds with outbreaks of h3n2 swine influenza were located by using a geographic information system and analyzed by using spatial analysis software. descriptive and spatial statistics, includin ... | 2008 | 18309747 |
| associations between pathogens in healthy pigs and pigs with pneumonia. | the aim of this study was to evaluate the associations between different pathogens in the development of pneumonia and bronchopneumonia in pigs. samples of bronchoalveolar lavage fluid from 100 pigs showing no clinical signs and 239 pigs with clinical signs of respiratory disease were examined for mycoplasma hyopneumoniae, mycoplasma hyorhinis, us-type porcine respiratory and reproductive syndrome virus (prrsv), eu-type prrsv, porcine circovirus type 2 (pcv-2), influenza virus type a, alpha-haem ... | 2008 | 18310558 |
| influenza virus and proteolytic bacteria co-infection in respiratory tract from individuals presenting respiratory manifestations. | a role for proteolytic bacteria in the exacerbation of influenza virus has been shown in natural hosts such as pigs and humans. four hundred seven samples were collected from the respiratory tract of individuals presenting clinical manifestations, during influenza season (2003-2005) in são paulo city. the aim of this study was to evaluate the incidence of determined bacteria co-infecting virus in human respiratory tract. tests, such as bacteriological, immunofluorescence (if), rt/pcr and hemaggl ... | 2008 | 18327486 |
| identification of amino acids in the ha of h3 influenza viruses that determine infectivity levels in primary swine respiratory epithelial cells. | in the late 1990s, triple reassortant h3n2 influenza a viruses emerged and spread widely within the swine population of the united states. we have shown previously that an isolate representative of this lineage of viruses, a/swine/minnesota/593/99 (sw/mn), has higher infectivity and accelerated replication kinetics in pigs, compared to a human-lineage h3n2 virus isolated from a pig during the same time period, a/swine/ontario/00130/97 (sw/ont [landolt, g.a., karasin, a.i., phillips, l., olsen, c ... | 2008 | 18329747 |
| origin of the 1918 spanish influenza virus: a comparative genomic analysis. | to test the avian-origin hypothesis of the 1918 spanish influenza virus we surveyed influenza sequences from a broad taxonomic distribution and collected 65 full-length genomes representing avian, human and "classic" swine h1n1 lineages in addition to numerous other swine (h1n2, h3n1, and h3n2), human (h2n2, h3n2, and h5n1), and avian (h1n1, h4n6, h5n1, h6n1, h6n6, h6n8, h7n3, h8n4, h9n2, and h13n2) subtypes. amino acids from all eight segments were concatenated, aligned, and used for phylogenet ... | 2008 | 18353690 |
| a brief introduction to the avian influenza virus. | the avian influenza (ai) virus is type a influenza isolated from and adapted to an avian host. type a influenza belongs to the orthomyxovirdae virus family, is enveloped, and is pleiomorphic with a size ranging from 80-120 nm (reviewed in [1]). type a influenza strains are classified by the serological subtypes of the primary viral surface proteins, the hemagglutinin (ha) and neuraminidase (na). the ha has 16 subtypes (h1-h16) and contains neutralizing epitopes. antibodies against the na are not ... | 2008 | 18370034 |
| evolving complexities of influenza virus and its receptors. | sialic acids (sias) are regarded as receptors for influenza viruses and are usually bound to galactose (gal) in an alpha2-3 or alpha2-6 configuration. the detection of these sia configurations in tissues has commonly been through the use of plant lectins that are able to identify which cells contain siaalpha2-3- and siaalpha2-6-linked glycans, although other techniques for receptor distribution have been used. initial experiments indicated that avian versus human influenza virus binding was dete ... | 2008 | 18375125 |
| prevention of avian influenza epidemic: what policy should we choose? | human-to-human transmission of the avian influenza has been extremely rarely reported, and is considered as limited, inefficient and unsustained. however, experts warn an occurrence of "mutant avian influenza", which can easily spread among humans, because the avian influenza is already endemic, in particular in asian poultry, and it is evolving in domestic and wild birds, pigs and humans. outbreak of such mutant avian influenza in the human world may have devastating consequences, which are com ... | 2008 | 18384816 |
| swine infection with h9n2 influenza viruses in china in 2004. | in 2004, h9n2 influenza a viruses were isolated from pigs with respiratory syndrome in commercial swine farms in henan province, china. antigenic and genetic characterization were performed for seven swine h9n2 influenza viruses. the hemagglutinin antigenicity of swine h9n2 viruses was similar to those of avian h9n2 viruses of a/duck/hong kong/y280/1997 (dk/hk/y280/97)-like sublineage prevalent in china. it is noteworthy that the neuraminidase of these isolates had no deletions in the stalk, whi ... | 2008 | 18401696 |
| isolation and genetic characterization of avian origin h9n2 influenza viruses from pigs in china. | as pigs are susceptible to infection with both avian and human influenza a viruses, they have been proposed to be an intermediate host for the adaptation of avian influenza viruses to humans. in april 2006, a disease caused by highly pathogenic porcine reproductive and respiratory syndrome virus (prrsv) occurred in several pig farms and subsequently overwhelmed almost half of china with more than 2,000,000 cases of pig infection. here we report a case in which four swine h9n2 influenza viruses w ... | 2008 | 18403137 |
| influenza exposure in united states feral swine populations. | swine play an important role in the disease ecology of influenza. having cellular receptors in common with birds and humans, swine provide opportunities for mixed infections and potential for genetic reassortment between avian, human, and porcine influenza. feral swine populations are rapidly expanding in both numbers and range and are increasingly coming into contact with waterfowl, humans, and agricultural operations. in this study, over 875 feral swine were sampled from six states across the ... | 2008 | 18436668 |
| [baculovirus expression and establishment of the indirect elisa for the ha gene of swine influenza virus h1 subtype]. | the hemagglutinin (ha) gene fragment of swine influenza virus a/swine/guangdong/lm/05(h1n1) was amplified with ha gene specific primers and cloned into baculovirus transfer plasmid pfastbacgp67b. the recombinant plasmid pfastbacgp67b-h1 was identified by restriction enzyme digestion and gene sequencing. following the transformation of dh10bac escherichia coli component cells by pfastbacgp67b-h1, recombinant bacmids rbacmid-h1 were identified by blue/white selection and pcr analysis. then recombi ... | 2008 | 18438005 |
| epidemiological survey of swine influenza a virus in selected wild boar populations in germany. | the aim of this study was to evaluate the epidemiological situation of swine influenza virus (siv) infections in different wild boar populations in germany based on a serological surveillance in some bundeslaender (federal states) in connection with virological investigations in wild boar shot in northern germany (mecklenburg-western pomerania, district of nordvorpommern). altogether, 1245 sera from wild boar were tested using the hemagglutination inhibition test. the established seroprevalence ... | 2008 | 18440732 |
| flow cytometric monitoring of influenza a virus infection in mdck cells during vaccine production. | in cell culture-based influenza vaccine production the monitoring of virus titres and cell physiology during infection is of great importance for process characterisation and optimisation. while conventional virus quantification methods give only virus titres in the culture broth, data obtained by fluorescence labelling of intracellular virus proteins provide additional information on infection dynamics. flow cytometry represents a valuable tool to investigate the influences of cultivation condi ... | 2008 | 18447925 |
| generation and evaluation of the trivalent inactivated reassortant vaccine using human, avian, and swine influenza a viruses. | reassortant technology was used to obtain three interspecific reassortant influenza viruses using three influenza viruses of a/puerto rico/8/34(h1n1), a/swine/hebei/1/2005(h3n2) and a/chicken/guangdong/126/2002(h9n2). the high-growth reassortant strains were h9/pr8, h3/h9n2 and h1/h9n2 that contained hemagglutinin (ha) and neuraminidase (na) genes from the inactivated parental viruses and the other 6 internal genes from the live parental viruses. the trivalent formalin-inactivated vaccine, conta ... | 2008 | 18448208 |
| [epizooty caused by high-virulent influenza virus a/h5n1 of genotype 2.2 (qinghai-siberian) among wild and domestic birds on the paths of fall migrations to the north-western part of the azov sea basin (krasnodar territory)]. | isolation, followed by the sequencing the full-size genome of strains of a/chicken/krasnodarl300/07 and a/cygnus cygnus/krasnodar/329/07, has shown that they belong to genotype 2.2 (qinghai-siberian). the strains were deposited at the state virus collection of the russian federation and nucleotide consequences were at the international databank genbank. the strains contained 10 unique amino acid replacements in reference to the consensus of the qinghai-siberian genotype in the pb2, pa, ha, na, a ... | 2008 | 18450104 |
| genetic characterization of h1n1, h1n2 and h3n2 swine influenza virus in thailand. | swine have been known to be a suitable host for influenza a virus. in thailand, phylogenetic analysis on swine influenza virus (siv) has as yet not been attempted. the present report presents molecular and phylogenetic analysis performed on siv in thailand. in this study, 12 siv isolates from the central and eastern part of thailand were subtyped and the molecular genetics of hemagglutinin and neuraminidase were elucidated. three subtypes, h1n1, h1n2 and h3n2, are described. phylogenetic analysi ... | 2008 | 18458812 |
| pathogenicity of a goose isolate of highly pathogenic h5n1 influenza a virus for chickens, mice, and pigs. | in recent years, a highly pathogenic avian influenza virus (aiv) h5n1 subtype has emerged as a pathogenic agens for a variety of species including humans. to investigate the pathogenicity of aiv, the isolate zfe/2004 (h5n1) was used to infect chickens, mice, and pigs. the results showed that the isolate showed attributes of the highly pathogenic aiv such as high pathogenicity index (intravenous pathogenicity index (ivpi) of 2.85 and intracerebral pathogenicity index (icpi) of 3.00) and a specifi ... | 2008 | 18459834 |
| molecular characterization of an h1n2 swine influenza virus isolated in miyazaki, japan, in 2006. | swine influenza virus (siv) was isolated from a farm in miyazaki prefecture in japan in july 2006. an isolate was genetically subtyped as h1n2 and was designated a/swine/miyazaki/1/2006 (h1n2). the nucleotide sequences of all eight viral rna segments were determined, and then phylogenetic analysis was performed using the neighbor-joining method. all segments were shown to be closely related to those of japanese siv h1n2 isolates, which have been circulating since the 1980s. the results indicate ... | 2008 | 18460842 |
| avian influenza in birds and mammals. | the disease syndromes caused by avian influenza viruses are highly variable depending on the host species infected, its susceptibility and response to infection and the virulence of the infecting viral strain. although avian influenza viruses have a broad host range in general, it is rare for an individual strain or subtype to infect more than one species. the h5n1 highly pathogenic avian influenza virus (hpaiv) lineages of viruses that descended from a/goose/guandong/96 (h5n1 hpaiv) are unusual ... | 2009 | 18485480 |
| one-step multiplex rt-pcr for detection and subtyping of swine influenza h1, h3, n1, n2 viruses in clinical samples using a dual priming oligonucleotide (dpo) system. | the swine influenza virus (siv) h1n1, h1n2, and h3n2 subtypes circulate in korean farm. a novel multiplex rt-pcr (m-rt-pcr) was developed to detect and subtype swine influenza viruses. this m-rt-pcr assay could identify h1, h3, n1 and n2 from clinical samples in single tube reaction using dpo system. korean sivs are closely related to the united states influenza viruses, and primers were developed for siv from north american viruses and recently korean isolates. the sensitivity of the m-rt-pcr w ... | 2008 | 18486976 |
| anti-ganglioside antibody induction by swine (a/nj/1976/h1n1) and other influenza vaccines: insights into vaccine-associated guillain-barré syndrome. | receipt of an a/nj/1976/h1n1 "swine flu" vaccine in 1976, unlike receipt of influenza vaccines used in subsequent years, was strongly associated with the development of the neurologic disorder guillain-barré syndrome (gbs). anti-ganglioside antibodies (e.g., anti-gm(1)) are associated with the development of gbs, and we hypothesized that the swine flu vaccine contained contaminating moieties (such as campylobacter jejuni antigens that mimic human gangliosides or other vaccine components) that el ... | 2008 | 18522505 |
| amino acid 226 in the hemagglutinin of h4n6 influenza virus determines binding affinity for alpha2,6-linked sialic acid and infectivity levels in primary swine and human respiratory epithelial cells. | avian lineage h4n6 influenza viruses previously isolated from pigs differ at hemagglutinin amino acids 226 and 228 from h4 subtype viruses isolated from birds. using a parental h4n6 swine isolate and hemagglutinin mutant viruses (at residues 226 and/or 228), we determined that viruses which contain l226 had a higher affinity for sialic acid alpha2,6 galactose (saalpha2,6gal) and a higher infectivity level for primary swine and human respiratory epithelial cells, whereas viruses which contain q22 ... | 2008 | 18550676 |
| streptococcus suis type 2 culture supernatant enhances the infection ability of the swine influenza virus h3 subtype in mdck cells. | swine influenza virus and streptococcus suis type 2 often occur as a clinical coinfection in pigs, the syndrome of which is more serious than the virus or bacterium sole infection. streptococcus suis type 2 can produce extracellular proteases, which may cleave hemagglutinin to enhance the infection ability of swine influenza virus. the current study investigated whether extracellular proteolytic culture supernatant of streptococcus suis type 2, isolated from jiangsu, enhanced the infection abili ... | 2008 | 18557523 |
| phylogenetic analysis of swine influenza viruses recently isolated in korea. | several influenza a viral subtypes were isolated from pigs during a severe outbreak of respiratory disease in korea during 2005 and 2006. they included a classical swine h1n1 subtype, two swine-human-avian triple-recombinant h1n2 subtypes, and a swine-human-avian triple-recombinant h3n2 subtype. in the current study, genetic characterization to determine the probable origin of these recent isolates was carried out for the first time. phylogenetic analysis indicated that all the recent korean iso ... | 2008 | 18574682 |
| [phylogenetic analysis of human/swine/avian gene reassortant h1n2 influenza a virus isolated from a pig in china]. | our aim in this study was to determine the genetic characterization and probable origin of the h1n2 swine influenza virus (a/swine/guangxi/13/2006) (sw/gx/13/06) from lung tissue of a pig in guangxi province, china. | 2008 | 18590231 |
| comparison of three serological assays to determine the cross-reactivity of antibodies from eight genetically diverse u.s. swine influenza viruses. | swine influenza virus is an economically important pathogen to the u.s. swine industry. new influenza subtypes and isolates within subtypes with different genetic and antigenic makeup have recently emerged in u.s. swineherds. as a result of the emergence of these new viruses, diagnosticians' ability to accurately diagnose influenza infection in pigs and develop appropriate vaccine strategies has become increasingly difficult. the current study compares the ability of subtype-specific commercial ... | 2008 | 18599846 |
| development of multiplex rt-pcr assays for rapid detection and subtyping of influenza type a viruses from clinical specimens. | we developed multiplex rt-pcr assays that can detect and identify 12 hemagglutinin (h1-h12) and 9 neuraminidase (n1-n9) subtypes that are commonly isolated from avian, swine, and human influenza a viruses. rt-pcr products with unique sizes characteristic of each subtype were amplified by multiplex rt-pcrs, and sequence analysis of each amplicon was demonstrated to be specific for each subtype with 24 reference viruses. the specificity was demonstrated further with dna or cdna templates from 7 vi ... | 2008 | 18600063 |
| [construction and immunogenicity analysis of antigenic epitopes of swine influenza virus]. | several antigen epitopes were designed according to the sequences of swine influenza virus hemagglutinin (ha) genes and lined with the interval. the gene was amplified by pcr and sub cloned into pet30a (+) vector. the fusion protein was expressed in e. coli bl21 (de3) by induced with iptg and purified by affinity chromatography. the molecular weight of the protein was about 20 kd in sds-page. immunological activity of the fusion protein was analyzed by western blot. the results showed that the f ... | 2008 | 18616184 |
| domestic pigs have low susceptibility to h5n1 highly pathogenic avian influenza viruses. | genetic reassortment of h5n1 highly pathogenic avian influenza viruses (hpai) with currently circulating human influenza a strains is one possibility that could lead to efficient human-to-human transmissibility. domestic pigs which are susceptible to infection with both human and avian influenza a viruses are one of the natural hosts where such reassortment events could occur. virological, histological and serological features of h5n1 virus infection in pigs were characterized in this study. two ... | 2008 | 18617994 |
| surveillance of avian and swine influenza in the swine population in taiwan, 2004. | we conducted serological and virological surveillance of pig farms in taiwan from areas epidemic for low pathogenic avian influenza virus (aiv), h5n2 subtype, in order to determine the prevalence of aiv and swine influenza virus (siv) in 2004. | 2008 | 18629419 |
| death as a study endpoint: consider non-medical treatments. | | 2008 | 18650816 |
| death as a study endpoint: try a pilot study. | | 2008 | 18650817 |
| death as a study endpoint. | | 2008 | 18650818 |
| death as a study endpoint: why use ferrets? | | 2008 | 18650819 |
| rapid microchip-based electrophoretic immunoassays for the detection of swine influenza virus. | towards developing rapid and portable diagnostics for detecting zoonotic diseases, we have developed microchip-based electrophoretic immunoassays for sensitive and rapid detection of viruses. two types of microchip-based electrophoretic immunoassays were developed. the initial assay used open channel electrophoresis and laser-induced fluorescence detection with a labeled antibody to detect influenza virus. however, this assay did not have adequate sensitivity to detect viruses at relevant concen ... | 2008 | 18651074 |
| 6-sulfo sialyl lewis x is the common receptor determinant recognized by h5, h6, h7 and h9 influenza viruses of terrestrial poultry. | influenza a viruses of domestic birds originate from the natural reservoir in aquatic birds as a result of interspecies transmission and adaptation to new host species. we previously noticed that influenza viruses isolated from distinct orders of aquatic and terrestrial birds may differ in their fine receptor-binding specificity by recognizing the structure of the inner parts of neu5ac alpha 2-3gal-terminated sialyloligosaccharide receptors. to further characterize these differences, we studied ... | 2008 | 18652681 |
| seroprevalence and risk factors for influenza a viruses in pigs in peninsular malaysia. | following a series of h5n1 cases in chickens and birds in a few states in malaysia, there was much interest in the influenza a viruses subtypes that circulate among the local pig populations. pigs may act as a mixing vessel for avian and mammal influenza viruses, resulting in new reassorted viruses. this study investigated the presence of antibodies against influenza h1n1 and h3n2 viruses in pigs from peninsular malaysia using herdcheck swine influenza h1n1 and h3n2 antibody test kits. at the sa ... | 2008 | 18667027 |
| design and synthesis of bioactive 1,2-annulated adamantane derivatives. | adamantanopyrrolidines 8, 9 and 10, adamantanopyrrolidines 16 and 18, adamantanoxazolone 20, adamantanopyrazolone 23, adamantanopyrazolothione 24 and adamantanocyclopentanamine 32 were synthesized and tested for anti-influenza a virus and trypanocidal activity. the stereoelectronic requirements for optimal antiviral and trypanocidal potency were investigated. pyrrolidine 16 proved to be the most active of the compounds tested against influenza a virus, being 4-fold more active than amantadine, e ... | 2008 | 18698478 |
| neutralizing antibodies derived from the b cells of 1918 influenza pandemic survivors. | investigation of the human antibody response to influenza virus infection has been largely limited to serology, with relatively little analysis at the molecular level. the 1918 h1n1 influenza virus pandemic was the most severe of the modern era. recent work has recovered the gene sequences of this unusual strain, so that the 1918 pandemic virus could be reconstituted to display its unique virulence phenotypes. however, little is known about adaptive immunity to this virus. we took advantage of t ... | 2008 | 18716625 |
| homologous recombination evidence in human and swine influenza a viruses. | dynamic gene mutation and the reassortment of genes have been considered as the key factors responsible for influenza a virus virulence and host tropism change. this study reports several significant evidence demonstrating that homologous recombination also takes place between influenza a viruses in human and swine lineages. moreover, in a mosaic descended from swine h1n1 subtype and human h2n2, we found that its minor putative parent might be a derivative from the human cold-adapted vaccine lin ... | 2008 | 18721995 |
| [the rescue of h1n1 subtype swine influenza virus]. | the swine influenza virus (siv) strain a/swine/tianjin/01/2004(h1n1) (a/s/tj/04) was rescued successfully by an eight-plasmid rescue system. the cdnas of siv 8 gene segments were synthesized by rt-pcr and cloned into the rna polymerase i/ii bidirection expression vector phw2000 independently, resulting in 8 recombinant plasmids. the 8 recombinant plasmids were cotransfected into cos-1 cell, 30 h later tpck-trypsin was added to 0.5 microg/ml. the cos-1 cell and supernatant were harvested 48 h aft ... | 2008 | 18724708 |
| human case of swine influenza a (h1n1) triple reassortant virus infection, wisconsin. | zoonotic infections with swine influenza a viruses are reported sporadically. triple reassortant swine influenza viruses have been isolated from pigs in the united states since 1998. we report a human case of upper respiratory illness associated with swine influenza a (h1n1) triple reassortant virus infection that occurred during 2005 following exposure to freshly killed pigs. | 2008 | 18760023 |
| detection of respiratory pathogens in air samples from acutely infected pigs. | pathogens causing significant respiratory disease in growing pigs include porcine reproductive and respiratory syndrome virus, porcine circovirus 2, swine influenza virus, porcine respiratory coronavirus, mycoplasma hyopneumoniae, and bordetella bronchiseptica. the objective of this research was to characterize the respiratory excretion of these pathogens by acutely infected pigs. pigs were inoculated under experimental conditions with 1 pathogen. samples were collected from the upper respirator ... | 2008 | 18783027 |
| h5n1 avian influenza virus induces apoptotic cell death in mammalian airway epithelial cells. | in recent years, the highly pathogenic avian influenza virus h5n1 has raised serious worldwide concern about an influenza pandemic; however, the biology of h5n1 pathogenesis is largely unknown. to elucidate the mechanism of h5n1 pathogenesis, we prepared primary airway epithelial cells from alveolar tissues from 1-year-old pigs and measured the growth kinetics of three avian h5 influenza viruses (a/crow/kyoto/53/2004 [h5n1], a/duck/hong kong/342/78 [h5n2], and a/duck/hong kong/820/80 [h5n3]), th ... | 2008 | 18787012 |
| seroprevalence and genetic evolutions of swine influenza viruses under vaccination pressure in korean swine herds. | an overall 8,427 total of blood samples collected from growing to finishing pigs were submitted for diagnosis of swine influenza virus infection between january 2002 and december 2006. sera from 2002 to 2005 were examined for antibodies against four different swine influenza subtypes using the hemagglutination inhibition test to investigate seroprevalence rates by natural infection in korean swine herds while nasal swabs and lung tissue samples were used for viral isolation. the natural infectio ... | 2008 | 18789984 |
| viral and bacterial serology of six free-ranging bearded seals erignathus barbatus. | serum or heparinized plasma samples were obtained from 3 male (2 adult and 1 weaned calf) and 3 adult female free-ranging bearded seals erignathus barbatus in may of 1994, 1995, or 1996. blood samples were obtained from animals taken in subsistence hunts near st. lawrence island, alaska and screened for antibodies to a suite of bacteria and viruses potentially pathogenic for pinnipeds and/or humans. no samples had detectable antibodies to brucella spp., phocine distemper virus, influenza a virus ... | 2008 | 18828565 |
| inhibition by egg-white of hemagglutination by swine influenza virus. | | 1948 | 18869331 |
| limited susceptibility and lack of systemic infection by an h3n2 swine influenza virus in intranasally inoculated chickens. | chickens were intranasally inoculated with the swine influenza virus (siv) a/swine/nc/307408/04 (h3n2) (nc/04 siv) to determine the infectivity of a north american siv for chickens, as well as the possibility of chicken meat serving as a transmission vehicle for siv. white leghorn (wl) layer-type chickens were used for initial pathotyping and infectivity tests, and a more comprehensive intranasal pathogenesis study was done with white plymouth rock (wpr) broiler-type chickens. none of the nc/04 ... | 2008 | 18939642 |
| pre-clinical development of cell culture (vero)-derived h5n1 pandemic vaccines. | the rapid spread of avian influenza (h5n1) and its transmission to humans has raised the possibility of an imminent pandemic and concerns over the ability of standard influenza vaccine production methods to supply sufficient amounts of an effective vaccine. we report here on a robust and flexible strategy which uses wild-type virus grown in a continuous cell culture (vero) system to produce an inactivated whole virus vaccine. candidate vaccines based on clade 1 and clade 2 influenza h5n1 strains ... | 2008 | 18953724 |
| design of multiplexed detection assays for identification of avian influenza a virus subtypes pathogenic to humans by smartcycler real-time reverse transcription-pcr. | influenza a virus (iav) epidemics are the result of human-to-human or poultry-to-human transmission. tracking seasonal outbreaks of iav and other avian influenza virus (aiv) subtypes that can infect humans, aquatic and migratory birds, poultry, and pigs is essential for epidemiological surveillance and outbreak alerts. in this study, we performed four real-time reverse transcription-pcr (rrt-pcr) assays for identification of the iav m and hemagglutinin (ha) genes from six known aivs infecting pi ... | 2009 | 18971359 |
| molecular cloning and characterization of porcine mx2 gene. | mx, an interferon-inducible protein, is found in various vertebrates and confers resistance to several rna viruses. at least two mx proteins occur in vertebrates, and these proteins are key components of innate defense against viral infection. in mice and humans, the two mx genes have different antiviral activities. both mx1 and mx2 have also been detected in pigs, although only a partial sequence of porcine mx2 has been reported, and there is no information on its antiviral activity. here, we r ... | 2009 | 18977535 |
| ongoing evolution of swine influenza viruses: a novel reassortant. | a novel h3n2 influenza virus strain isolated in germany from pigs with clinical symptoms of influenza is described. it was characterised by neutralisation test, hemagglutination inhibition test and complete sequencing of the genome. the data demonstrate the emergence of a h3n2 reassortant with the human-like hah3 gene of prevalent european porcine h3n2 influenza viruses and a nan2 gene of the european porcine h1n2 viruses. the gene segments of the internal proteins are avian-like, consistent wit ... | 2008 | 18985274 |
| antigenic structure of the hemagglutinin of h9n2 influenza viruses. | the hemagglutinins (has) of h9 influenza viruses isolated from birds and mammals of different species were antigenically and genetically analyzed. antigenic variants were selected from a/swine/hong kong/10/98 (h9n2) and a/duck/hokkaido/13/00 (h9n2) in the presence of monoclonal antibodies (mabs). based on the reactivity patterns of these mutants with a panel of mabs, at least five non-overlapping antigenic sites were defined using eight mabs which recognized seven distinct epitopes on the h9 ha ... | 2008 | 18989614 |
| the animal-human interface and infectious disease in industrial food animal production: rethinking biosecurity and biocontainment. | understanding interactions between animals and humans is critical in preventing outbreaks of zoonotic disease. this is particularly important for avian influenza. food animal production has been transformed since the 1918 influenza pandemic. poultry and swine production have changed from small-scale methods to industrial-scale operations. there is substantial evidence of pathogen movement between and among these industrial facilities, release to the external environment, and exposure to farm wor ... | 2008 | 19006971 |
| fusion of c3d with hemagglutinin enhances protective immunity against swine influenza virus. | h1n1 and h3n2 are the dominant subtypes causing swine influenza in china and other countries. it is important to develop effective vaccines against both h1n1 and h3n2 subtypes of swine influenza virus (siv). we examined the effects of a dna vaccine expressing an influenza ha fused to three copies of murine complement c3d in mice. plasmids encoding soluble ha (sha), complete ha (tmha), or a soluble fused form of ha (sha-mc3d3) were constructed from the h3n2 subtype of siv. the immune response was ... | 2009 | 19010505 |
| [cloning and phylogenetic analysis of the entire gene of an h1n1 subtype swine influenza virus isolated from guangdong province]. | to study the genetic variation and evolutionary characteristics of h1n1 swine influenza virus, all the eight genes of lm were amplified by rt- pcr, cloned into pmd18-t vector and sequenced respectively. the results showed that neither insertion nor deletion was observed in nucleotides of lm. the amino acids sequence of cleavage site of ha is ipsiqsr decrease g, suggesting that lm did not have the molecular characteristics of high pathogen. ha had highly conservative n-glycosylation site at posit ... | 2008 | 19035324 |
| pb2 protein of a highly pathogenic avian influenza virus strain a/chicken/yamaguchi/7/2004 (h5n1) determines its replication potential in pigs. | it has been shown that not all but most of the avian influenza viruses replicate in the upper respiratory tract of pigs (h. kida et al., j. gen. virol. 75:2183-2188, 1994). it was shown that a/chicken/yamaguchi/7/2004 (h5n1) [ck/yamaguchi/04 (h5n1)] did not replicate in pigs (n. isoda et al., arch. virol. 151:1267-1279, 2006). in the present study, the genetic basis for this host range restriction was determined using reassortant viruses generated between ck/yamaguchi/04 (h5n1) and a/swine/hokka ... | 2009 | 19052090 |
| occurrence of swine influenza virus infection in swine with porcine respiratory disease complex. | we studied the occurrence of swine influenza virus (siv) infection in piglets with respiratory symptoms resembling porcine respiratory disease complex (prdc). a total of 106 samples including nasal swab and lung suspension from sick piglets were collected from 30 farms of medium size in the central and eastern parts of thailand from august 2006 to february 2007. samples were inoculated onto mardin-darby canine kidney (mdck) cells and siv infection was confirmed by immunofluorescent assay (ifa) a ... | 2008 | 19062693 |
| further evidence for infection of pigs with human-like h1n1 influenza viruses in china. | classical swine and avian-like h1n1 influenza viruses were reported widely in swine population worldwide, but human-like h1n1 swine viruses were reported occasionally. in 2006, a human-like h1n1 swine virus (a/swine/guangdong/96/06) was isolated from pigs in guangdong province, which was reported in china for the first time. to get further evidence for infection of pigs with human-like h1n1 influenza viruses, we analyzed eight gene segments of three human-like swine h1n1 viruses (a/swine/guangdo ... | 2009 | 19063926 |
| swine influenza viruses a north american perspective. | influenza is a zoonotic viral disease that represents a health and economic threat to both humans and animals worldwide. swine influenza (si) was first recognized clinically in pigs in the midwestern u.s., in 1918, coinciding with the human influenza pandemic known as the spanish flu. since that time si has remained of importance to the swine industry throughout the world. in this review, the epidemiology of swine influenza virus (siv) infection in north american pigs is described in detail. the ... | 2008 | 19081490 |
| genetic correlation between h3n2 human and swine influenza viruses. | h3n2 is one of the main subtypes of influenza virus which circulates in human and swine population throughout the world. | 2009 | 19083267 |
| analytical sensitivity of air samplers based on uniform point-source exposure to airborne porcine reproductive and respiratory syndrome virus and swine influenza virus. | research and surveillance activities involving airborne pathogens rely on the capture and enumeration of pathogens suspended in aerosols. the objective of this study was to estimate the analytical sensitivity (detection threshold) of each of 4 air samplers for porcine reproductive and respiratory syndrome virus (prrsv) and swine influenza virus (siv). in a 5-min sampling period under controlled conditions, the analytical sensitivity of the agi-30 (ace glass, vineland, new jersey, usa), agi-4 (ac ... | 2008 | 19086377 |
| characterization of a canadian mink h3n2 influenza a virus isolate genetically related to triple reassortant swine influenza virus. | in 2007, an h3n2 influenza a virus was isolated from canadian mink. this virus was found to be phylogenetically related to a triple reassortant influenza virus which emerged in canadian swine in 2005, but it is antigenically distinct. the transmission of the virus from swine to mink seems to have occurred following the feeding of animals with a ration composed of uncooked meat by-products of swine obtained from slaughterhouse facilities. serological analyses suggest that the mink influenza virus ... | 2009 | 19116358 |
| performance of a commercial swine influenza virus h1n1 and h3n2 antibody enzyme-linked immunosorbent assay in pigs experimentally infected with european influenza viruses. | the idexx swine influenza virus h1n1 and h3n2 enzyme-linked immunosorbent assays (elisas) are used worldwide, but their capacity to detect antibodies to european swine influenza viruses (sivs) has not been documented. a total of 313 well-defined sera from siv seronegative pigs and pigs experimentally infected with european sivs were used to compare the performance of both elisas and the hemagglutination inhibition (hi) test. the elisas largely failed to detect pigs that had been infected with h1 ... | 2009 | 19139506 |
| reverse genetics-generated elastase-dependent swine influenza viruses are attenuated in pigs. | influenza a virus causes significant morbidity in swine, resulting in a substantial economic burden. swine influenza virus (siv) infection also poses important human public health concerns. it has been shown that conversion of the haemagglutinin (ha) cleavage site from a trypsin-sensitive motif to an elastase-sensitive motif resulted in attenuated viruses in mouse models. however, application of this attenuation approach in a natural host has not been achieved yet. here, we report that using rev ... | 2009 | 19141446 |
| [infection of pigs with influenza a/h4 and a/h5 viruses isolated from wild birds on the territory of russia]. | pigs were intranasally infected with avian influenza a/h5 (h5n1, h5n3) and a/h4 (h4n6, h4n8) viruses in mono- and coinfection. infection with both apathogenic and pathogenic strains caused no clinical manifestations. a virus and/or fragments of its genome retained in nasopharyngeal fluid as long as 6-8 days after infection. during monoinfection, the structure of the hemagglutinin (ha) receptor site of isolates from the pigs infected with a/h5n1 strains (a/chicken/kurgan/3/2005, a/duck/russia/535 ... | 2008 | 19172904 |
| animal models for the study of influenza pathogenesis and therapy. | influenza a viruses causes a variety of illnesses in humans. the most common infection, seasonal influenza, is usually a mild, self-limited febrile syndrome, but it can be more severe in infants, the elderly, and immunodeficient persons, in whom it can progress to severe viral pneumonitis or be complicated by bacterial superinfection, leading to pneumonia and sepsis. seasonal influenza also occasionally results in neurologic complications. rarely, viruses that have spread from wild birds to dome ... | 2009 | 19176218 |
| population dynamics of swine influenza virus in farrow-to-finish and specialised finishing herds in the netherlands. | influenza virus infections with subtypes h1n1, h3n2 and h1n2 are very common in domestic pigs in europe. data on possible differences of population dynamics in finishing pigs in farrow-to-finish herds and in specialised finishing herds are, however, scarce. the presence of sows and weaned piglets on the same premises may, however, affect the exposure of finishing pigs to influenza viruses. in a longitudinal study on 14 farrow-to-finish herds and 15 finishing herds, groups of pigs were followed b ... | 2009 | 19181461 |
| characterization of an influenza a virus isolated from pigs during an outbreak of respiratory disease in swine and people during a county fair in the united states. | in august 2007, pigs and people became clinically affected by an influenza-like illness during attendance at an ohio county fair. influenza a virus was identified from pigs and people, and the virus isolates were characterized as swine h1n1 similar to swine viruses currently circulating in the u.s. pig population. the swine isolate, a/sw/oh/511445/2007 (oh07), was evaluated in an experimental challenge and transmission study reported here. our results indicate that the oh07 virus was pathogenic ... | 2009 | 19203846 |
| high prevalence of amantadine resistance among circulating european porcine influenza a viruses. | genetic analysis of the m2 sequence of european porcine influenza a viruses reveals a high prevalence of amantadine resistance due to the substitution of serine 31 by asparagine in all three circulating subtypes, h1n1, h3n2 and h1n2. the m segment of all resistant strains belongs to a single genetic lineage. whereas the first amantadine-resistant porcine strain was isolated in 1989, isolation of the last amantadine-susceptible strain dates to 1987, suggesting a displacement of amantadine-suscept ... | 2009 | 19223487 |
| experimental infection of pigs with the human 1918 pandemic influenza virus. | swine influenza was first recognized as a disease entity during the 1918 "spanish flu" pandemic. the aim of this work was to determine the virulence of a plasmid-derived human 1918 pandemic h1n1 influenza virus (reconstructed 1918, or 1918/rec, virus) in swine using a plasmid-derived a/swine/iowa/15/1930 h1n1 virus (1930/rec virus), representing the first isolated influenza virus, as a reference. four-week-old piglets were inoculated intratracheally with either the 1930/rec or the 1918/rec virus ... | 2009 | 19224986 |
| serological survey on aujeszky's disease, swine influenza and porcine reproductive and respiratory syndrome virus infections in italian pigs. | aujeszky's disease (ad), porcine reproductive and respiratory syndrome (prrs) and swine influenza (si) are among the principal agents of respiratory diseases of pigs. the aim of the study was to determine the prevalence of antibodies to shv-1, prrsv and siv in pigs reared in sicily. an enzyme linked immunosorbent assay for the glicoprotein ge of pseudorabies virus, for prrsv and for siv was performed. antibodies against ge of shv-1 were detected in 171 serum samples (14.6%), whereas prrsv antibo ... | 2008 | 19227130 |
| animal influenza epidemiology. | influenza a viruses exist within their natural host, aquatic birds, in a number of antigenic subtypes. only a few of these subtypes have successfully crossed into other avian and mammalian hosts. this brief review will focus on just three examples of viruses that have successfully passed between species; avian h5ni1 and h9n2 viruses and h3n2 viruses which have transmitted from aquatic birds to humans and then to swine. although there are a number of other subtypes that have also transmitted succ ... | 2008 | 19230163 |
| human case of swine influenza a (h1n1), aragon, spain, november 2008. | a human case of swine influenza a (h1n1) in a 50-year-old woman from a village near teruel (aragon, in the north-east of spain), with a population of about 200 inhabitants, has been reported in november 2008. | 2009 | 19232228 |
| a human case of swine influenza virus infection in europe--implications for human health and research. | swine are susceptible to the same influenza a virus subtypes as humans--h1n1, h3n2 and h1n2--and the histories of influenza in pigs and people are closely linked. many swine influenza viruses are a result of reassortment and their genes are composed of human and avian and/or swine virus genes. indeed, it is known that both human and avian influenza viruses occasionally transmit to pigs, and that pigs can serve as "mixing vessels" for these viruses, meaning that viruses can exchange genetic mater ... | 2009 | 19232229 |
| [preparation of monoclonal antibodies against ha protein of subtype h1 of swine influenza virus]. | to prepare the monoclonal antibodies(mab) against the ha protein of subtype h1 of swine influenza virus (siv). | 2009 | 19257989 |
| facing pandemic influenza threats: the importance of including poultry and swine workers in preparedness plans. | recent research has shown that poultry and swine workers, especially those with intense exposures, are at increased risk of zoonotic influenza virus infections. in multiple studies, us poultry workers and poultry veterinarians have evidence of previous infections with avian influenza virus. similarly, us swine workers have strong evidence of previous and acute infections with swine influenza viruses. mathematical modeling has demonstrated that such workers may accelerate the spread of pandemic v ... | 2009 | 19276439 |
| a comparison of the pathogenicity of avian and swine h5n1 influenza viruses in indonesia. | highly pathogenic avian influenza h5n1 viruses are circulating in many countries. we recently discovered that these viruses have been transmitted to pigs on multiple occasions in indonesia. to investigate whether avian h5n1 influenza viruses adapted to mammals through their introduction into pigs, we examined the growth of avian and swine isolates in cell culture and compared their pathogenicity in mice. we found that swine isolates were less virulent to mice than avian isolates, suggesting that ... | 2009 | 19288052 |
| different evolutionary trajectories of european avian-like and classical swine h1n1 influenza a viruses. | in 1979, a lineage of avian-like h1n1 influenza a viruses emerged in european swine populations independently from the classical swine h1n1 virus lineage that had circulated in pigs since the spanish influenza pandemic of 1918. to determine whether these two distinct lineages of swine-adapted a/h1n1 viruses evolved from avian-like a/h1n1 ancestors in similar ways, as might be expected given their common host species and origin, we compared patterns of nucleotide and amino acid change in whole ge ... | 2009 | 19297491 |
| pathogenesis of swine influenza virus (thai isolates) in weanling pigs: an experimental trial. | the objective of this study is to investigate the pathogenesis of swine influenza virus (siv) subtype h1n1 and h3n2 (thai isolates) in 22-day-old spf pigs. | 2009 | 19317918 |
| panorama phylogenetic diversity and distribution of type a influenza virus. | type a influenza virus is one of important pathogens of various animals, including humans, pigs, horses, marine mammals and birds. currently, the viral type has been classified into 16 hemagglutinin and 9 neuraminidase subtypes, but the phylogenetic diversity and distribution within the viral type largely remain unclear from the whole view. | 2009 | 19325912 |
| [development and preclinical study of new generation virosomal split influenza vaccine "grifor"]. | new russian virosomal split vaccine against influenza "grifor" was developed. the vaccine is represented by mix of highly purified protective external and internal antigens of influenza a (h1n1 and h3n2) and b viruses. developed technology of manufacture allowed to provide presentation of external antigens of influenza virus in the form of virosomes, and presentation of internal antigens in the form of micelles with maximal preservation of their antigenic activity. using electron microscopy, ele ... | 2009 | 19338232 |
| parotitis in a child infected with triple-reassortant influenza a virus in canada in 2007. | swine h3n2 influenza virus designated a/ontario/1252/2007 was isolated from a child with parotitis. diagnosis was confirmed by viral isolation and serological assays. a/ontario/1252/2007 was related to h3n2 triple reassortants that emerged in swine in the united states in 1998. three of five tested household members were also seropositive for a/ontario/1252/2007. | 2009 | 19339469 |
| multiple amino acid substitutions are involved in the adaptation of h9n2 avian influenza virus to mice. | to explore adaptation of avian influenza virus to mice we previously performed serial lung-to-lung passages of the influenza a/chicken/jiangsu/7/2002 (h9n2) strain, resulting in the isolation of a variant influenza strain lethal for mice. we now report that virulence correlates with improved growth characteristics on mammalian cells and extended tissue tropism in vivo. sequencing of the complete genomes of the wild-type and mouse-adapted viruses revealed 25 amino acid substitutions. some were fo ... | 2009 | 19342184 |
| isolation and genetic characterization of h5n2 influenza viruses from pigs in korea. | due to dual susceptibility to both human and avian influenza a viruses, pigs are believed to be effective intermediate hosts for the spread and production of new viruses with pandemic potential. in early 2008, two swine h5n2 viruses were isolated from our routine swine surveillance in korea. the sequencing and phylogenetic analysis of surface proteins revealed that the sw/korea/c12/08 and sw/korea/c13/08 viruses were derived from avian influenza viruses of the eurasian lineage. however, although ... | 2009 | 19359528 |
| minimal molecular constraints for respiratory droplet transmission of an avian-human h9n2 influenza a virus. | pandemic influenza requires interspecies transmission of an influenza virus with a novel hemagglutinin (ha) subtytpe that can adapt to its new host through either reassortment or point mutations and transmit by aerosolized respiratory droplets. two previous pandemics of 1957 and 1968 resulted from the reassortment of low pathogenic avian viruses and human subtypes of that period; however, conditions leading to a pandemic virus are still poorly understood. given the endemic situation of avian h9n ... | 2009 | 19380727 |
| conserved amino acid markers from past influenza pandemic strains. | finding the amino acid mutations that affect the severity of influenza infections remains an open and challenging problem. of special interest is better understanding how current circulating influenza strains could evolve into a new pandemic strain. influenza proteomes from distinct viral phenotype classes were searched for class specific amino acid mutations conserved in past pandemics, using reverse engineered linear classifiers. | 2009 | 19386124 |
| swine influenza a (h1n1) infection in two children--southern california, march-april 2009. | on april 17, 2009, cdc determined that two cases of febrile respiratory illness occurring in children who resided in adjacent counties in southern california were caused by infection with a swine influenza a (h1n1) virus. the viruses from the two cases are closely related genetically, resistant to amantadine and rimantadine, and contain a unique combination of gene segments that previously has not been reported among swine or human influenza viruses in the united states or elsewhere. neither chi ... | 2009 | 19390508 |
| isolation and molecular characterization of equine h3n8 influenza viruses from pigs in china. | during 2004-2006 swine influenza virus surveillance, two strains of h3n8 influenza viruses were isolated from pigs in central china. sequence and phylogenetic analyses of eight gene segments revealed that the two swine isolates were of equine origin and most closely related to european equine h3n8 influenza viruses from the early 1990s. comparison of hemagglutinin (ha) amino acid sequences showed several important substitutions. one substitution caused the loss of a potential glycosylation site, ... | 2009 | 19396578 |
| novel swine influenza virus subtype h3n1 in italy. | to date, three subtypes of swine influenza viruses, h1n1, h1n2, and h3n2 have been isolated in italy. in 2006, a novel swine influenza virus subtype (h3n1) was isolated from coughing pigs. rt-pcr performed on lung tissues, experimental infection in pigs with the novel isolate, and cloning the virus by plaque assay confirmed this unique h and n combination. the novel isolate was also antigenically and genetically characterized. genetic and phylogenetic analysis showed that the complete ha gene of ... | 2009 | 19398171 |
| swine flu could come back in more virulent form after summer, european experts say. | | 2009 | 19403576 |
| health department starts to stockpile masks for clinicians to combat swine flu. | | 2009 | 19403577 |
| outbreak news. swine influenza. | | 2009 | 19405211 |
| swine flu. | | 2009 | 19406879 |
| infectious diseases. as swine flu circles globe, scientists grapple with basic questions. | | 2009 | 19407164 |