Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| 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 |
| 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 |
| 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 |
| [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 |
| 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 |
| 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 |
| genetic evolution of swine influenza a (h3n2) viruses in china from 1970 to 2006. | pigs are susceptible to both human and avian influenza viruses and have been proposed to be intermediate hosts, or mixing vessels, for the generation of pandemic influenza viruses through reassortment or adaptation to the mammalian host. in this study, we summarize and report for the first time the coexistence of wholly human-like h3n2 viruses, double-reassortant h3n2 viruses, and triple-reassortant h3n2 viruses in pigs in china by analyzing the eight genes of swine influenza a (h3n2) viruses fo ... | 2008 | 18199784 |
| [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 |
| genetic and antigenic relatedness of h3 subtype influenza a viruses isolated from avian and mammalian species. | in 2004, we isolated triple reassortant h3n2 influenza viruses from turkey breeder hens in ohio and illinois. the illinois flock was vaccinated twice with an inactivated h3n2 vaccine containing a swine origin virus before the outbreak. additionally, a commercial inactivated vaccine containing an h3n4 virus of duck origin is being used in some turkey breeders. this prompted us to initiate a comparative study on the antigenic and genetic relatedness of various h3 subtype influenza viruses isolated ... | 2008 | 18206275 |
| structural basis for the function and inhibition of an influenza virus proton channel. | the m2 protein from influenza a virus is a ph-activated proton channel that mediates acidification of the interior of viral particles entrapped in endosomes. m2 is the target of the anti-influenza drugs amantadine and rimantadine; recently, resistance to these drugs in humans, birds and pigs has reached more than 90% (ref. 1). here we describe the crystal structure of the transmembrane-spanning region of the homotetrameric protein in the presence and absence of the channel-blocking drug amantadi ... | 2008 | 18235504 |
| 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 |
| highly pathogenic rna viral infections: challenges for antiviral research. | a number of rna viruses can cause severe disease when transmitted to humans from an animal reservoir. one of them, the recently emerged h5n1 subtype of influenza a virus, has caused several hundred cases of severe disease when transferred directly from domestic poultry. this or another avian subtype could potentially evolve to a form more transmissible by the respiratory route or reassort with a circulating strain to initiate a pandemic. other zoonotic rna viruses cause sporadic single cases or ... | 2008 | 18243346 |
| genetic analysis of four porcine avian influenza viruses isolated from shandong, china. | a bayesian phylogenetic analysis of eight separate gene segments indicated a/swine/shandong/2/2003 (h5n1), a/swine/shandong/na/2003 (h9n2), a/swine/shandong/nb/2003 (h9n2) and a/swine/shandong/nc/2005 (h9n2) probably represent two multiple reassortant lineages, that had not been described before, with genes coming from h5n1, h9n2 and other lineages from poultry in asia. amino acid motifs within the haemagglutinin sequence of a/swine/shandong/nb/2003 suggested it may be able to infect people, whe ... | 2008 | 18000640 |
| novel reassortant of swine influenza h1n2 virus in germany. | european porcine h1n2 influenza viruses arose after multiple reassortment steps involving a porcine influenza virus with avian-influenza-like internal segments and human h1n1 and h3n2 viruses in 1994. in germany, h1n2 swine influenza viruses first appeared in 2000. two german h1n2 swine influenza virus strains isolated from pigs with clinical symptoms of influenza are described. they were characterized by the neutralization test, haemagglutination inhibition (hi) test and complete sequencing of ... | 2008 | 18089751 |
| 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 |
| 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 |
| investigation of exposure to swine influenza viruses in ontario (canada) finisher herds in 2004 and 2005. | the epidemiology of influenza in the north american swine population has changed since the emergence of a triple-reassortant h3n2 influenza virus. although seen previously in north america, the ontario swine population had likely been free of viruses of the reassortant h3n2 lineage until 2005. the objective of this study was to investigate the frequency and distribution of exposure to h1n1 and h3n2 subtypes in the ontario finisher pig population prior to and after the h3n2 outbreak that occurred ... | 2008 | 17604859 |
| purification and cdna cloning of a novel protease inhibitor secreted into culture supernatant by mdck cells. | the infectivity of influenza viruses to host cells depends on the activation of the viral glycoprotein hemagglutinin (ha) by proteases. starting from the observation that influenza virus replication in mdck (madin darby canine kidney) cells was impaired by inactivation of trypsin in the culture fluids, we demonstrated that the inhibitory activity was resolved into two trypsin-inactivating factors (tf), tf a (15 kda) and tf b (11 kda). n-terminal protein sequences of the factors revealed that tf ... | 2008 | 17892946 |
| 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 |
| evolutionary analyses of european h1n2 swine influenza a virus by placing timestamps on the multiple reassortment events. | a novel h1n2 swine influenza a virus emerged in europe since 1994. previous phylogenetic analyses revealed that its genome segments were derived from h1n1 human virus, h3n2 human virus and avian-like h1n1/h3n2 swine virus, indicating the possibility of multiple reassortments events. however, dates of these reassortment events have not been investigated systematically. in this study, we used both global and local molecular clock concepts in a maximum likelihood framework to extrapolate the times ... | 2008 | 17936394 |
| 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 |
| a naturally occurring deletion in its ns gene contributes to the attenuation of an h5n1 swine influenza virus in chickens. | in 2001 and 2003, we isolated two h5n1 viruses, a/swine/fujian/1/01 (sw/fj/01) and a/swine/fujian/1/03 (sw/fj/03), from pigs in fujian province, southern china. genetically, these two viruses are similar, although the ns gene of the sw/fj/03 virus has a 15-nucleotide deletion at coding positions 612 to 626. the sw/fj/01 virus is highly lethal for chickens, whereas the sw/fj/03 virus is nonpathogenic for chickens when administrated intravenously or intranasally. to understand the molecular basis ... | 2008 | 17942562 |
| the antibody responses to swine influenza virus (siv) recombinant matrix 1 (rm1), matrix 2 (m2), and hemagglutinin (ha) proteins in pigs with different siv exposure. | the influenza invariant matrix 2 (m2) protein is a potential subunit vaccine candidate to induce protective immunity against broader strains of influenza a viruses (iav). antibodies to m2 protein have not been well characterized in iav natural hosts. to characterize m2-specific antibodies in pigs, an elisa to the extracellular region of the m2 (m2e) protein was developed. sera from pigs experimentally infected with three different swine influenza virus (siv) subtypes, immunized with an siv inact ... | 2008 | 17719187 |
| influenza vaccines and vaccination strategies in birds. | although it is well accepted that the present asian h5n1 panzootic is predominantly an animal health problem, the human health implications and the risk of human pandemic have highlighted the need for more information and collaboration in the field of veterinary and human health. h5 and h7 avian influenza (ai) viruses have the unique property of becoming highly pathogenic (hpai) during circulation in poultry. therefore, the final objective of poultry vaccination against ai must be eradication of ... | 2008 | 17889937 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| [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 |
| 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 |
| 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 |
| [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 |
| 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 |
| [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 |
| 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 | |
| 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 |
| [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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| seroprevalence of h1n1, h3n2 and h1n2 influenza viruses in pigs in seven european countries in 2002-2003. | avian-like h1n1 and human-like h3n2 swine influenza viruses (siv) have been considered widespread among pigs in western europe since the 1980s, and a novel h1n2 reassortant with a human-like h1 emerged in the mid 1990s. this study, which was part of the ec-funded 'european surveillance network for influenza in pigs 1', aimed to determine the seroprevalence of the h1n2 virus in different european regions and to compare the relative prevalences of each siv between regions. | 2008 | 19453469 |
| 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 |
| failure of protection and enhanced pneumonia with a us h1n2 swine influenza virus in pigs vaccinated with an inactivated classical swine h1n1 vaccine. | two us swine influenza virus (siv) isolates, a/swine/iowa/15/1930 h1n1 (ia30) and a/swine/minnesota/00194/2003 h1n2 (mn03), were evaluated in an in vivo vaccination and challenge model. inactivated vaccines were prepared from each isolate and used to immunize conventional pigs, followed by challenge with homologous or heterologous virus. both inactivated vaccines provided complete protection against homologous challenge. however, the ia30 vaccine failed to protect against the heterologous mn03 c ... | 2008 | 17719188 |
| prevalence of and risk factors for influenza in southern ontario swine herds in 2001 and 2003. | this research included 2 prevalence studies and a risk-factor investigation conducted in 2001 at 93 sites with sows only, finishers only, or both. in 2001, 1300 serum samples from sows in 65 herds and 720 serum samples from finisher pigs in 72 herds were tested for antibodies to swine influenzavirus (siv) of h1n1 subtype with an enzyme-linked immunosorbent assay (elisa). in 2003, 1140 serum samples from sows in 76 herds were tested for antibodies to siv of h3n2 subtype with a hemagglutination-in ... | 2008 | 18214156 |
| isolation and genetic characterization of avian-like h1n1 and novel ressortant h1n2 influenza viruses from pigs in china. | as pigs are susceptible to both human and avian influenza viruses, they have been proposed to be intermediate hosts or mixing vessels for the generation of pandemic influenza viruses through reassortment or adaptation to the mammalian host. in this study, we reported avian-like h1n1 and novel ressortant h1n2 influenza viruses from pigs in china. homology and phylogenetic analyses showed that the h1n1 virus (a/swine/zhejiang/1/07) was closely to avian-like h1n1 viruses and seemed to be derived fr ... | 2009 | 19460353 |
| swine flu advice for dentists issued. | 2009 | 19461605 | |
| high genetic and antigenic similarity between a swine h3n2 influenza a virus and a prior human influenza vaccine virus: a possible immune pressure-driven cross-species transmission. | in late april of 2009, a global outbreak of human influenza was reported. the causative agent is a highly unusual reassortant h1n1 influenza virus carrying genetic segments derived from swine, human and avian influenza viruses. in this study, we compared the ha, na and other gene segments of a swine h3n2 influenza a virus, a/swine/guangdong/z5/2003, which was isolated from pigs in 2003 in guangdong province, china, to the predominant human and swine h3n2 viruses. we found that the similarity of ... | 2009 | 19463787 |
| molecular characterization of low pathogenic avian influenza viruses, isolated from food products imported into singapore. | we have completed the genetic characterization of all eight gene segments for four low pathogenic avian influenza (lpai) viruses. the objective of this study was to detect the presence of novel signatures that may serve as early warning indicators of the conversion of lpai viruses to high pathogenic avian influenza (hpai) viruses. this study included three h5n2 and one h5n3 viruses that were isolated from live poultry imported into singapore as part of the national avian influenza virus (aiv) su ... | 2009 | 19464126 |
| antigenic and genetic characteristics of swine-origin 2009 a(h1n1) influenza viruses circulating in humans. | since its identification in april 2009, an a(h1n1) virus containing a unique combination of gene segments from both north american and eurasian swine lineages has continued to circulate in humans. the lack of similarity between the 2009 a(h1n1) virus and its nearest relatives indicates that its gene segments have been circulating undetected for an extended period. its low genetic diversity suggests that the introduction into humans was a single event or multiple events of similar viruses. molecu ... | 2009 | 19465683 |
| interspecies transmission and host restriction of avian h5n1 influenza virus. | long-term endemicity of avian h5n1 influenza virus in poultry and continuous sporadic human infections in several countries has raised the concern of another potential pandemic influenza. suspicion of the avian origin of the previous pandemics results in the close investigation of the mechanism of interspecies transmission. entry and fusion is the first step for the h5n1 influenza virus to get into the host cells affecting the host ranges. therefore receptor usage study has been a major focus fo ... | 2009 | 19471865 |
| confirmation of the first hong kong case of human infection by novel swine origin influenza a (h1n1) virus diagnosed using ultrarapid, real-time reverse transcriptase pcr. | 2009 | 19474268 | |
| geographic dependence, surveillance, and origins of the 2009 influenza a (h1n1) virus. | 2009 | 19474418 | |
| evolution of the m gene of the influenza a virus in different host species: large-scale sequence analysis. | influenza a virus infects not only humans, but also other species including avian and swine. if a novel influenza a subtype acquires the ability to spread between humans efficiently, it could cause the next pandemic. therefore it is necessary to understand the evolutionary processes of influenza a viruses in various hosts in order to gain better knowledge about the emergence of pandemic virus. the virus has segmented rna genome and 7th segment, m gene, encodes 2 proteins. m1 is a matrix protein ... | 2009 | 19476650 |
| characterization of triple reassortant h1n1 influenza a viruses from swine in ohio. | an h1n1 influenza a virus, a/swine/ohio/24366/07, was isolated from pigs in an ohio county fair. twenty-six people who came in contact with the infected pigs developed respiratory disease and two of these people were laboratory confirmed as h1n1 by the centers for disease control and prevention (cdc). the a/swine/ohio/24366/07 virus we isolated from swine was shown at the cdc to have 100% identical genome sequence to the human virus associated with the county fair. this prompted us to characteri ... | 2009 | 19477087 |
| april 2009: an outbreak of swine-origin influenza a(h1n1) virus with evidence for human-to-human transmission. | a swine-origin influenza a(h1n1) virus is currently responsible for an outbreak of infections in the human population, with laboratory-confirmed cases reported in several countries and clear evidence for human-to-human transmission. we provide a description of the outbreak at the end of april 2009, and a brief review of the zoonotic potential of swine influenza viruses. | 2009 | 19442755 |
| africa and swine influenza virus. | 2009 | 19480028 | |
| genetic characterization of h1n1 swine influenza a viruses isolated in eastern china. | three influenza h1n1 viruses were isolated in 2005 from pigs with respiratory disease on a farm in eastern china. the three isolates were characterized to determine their probable origin. each of the eight genes of the isolates was most closely related to the corresponding gene from the classical swine h1n1 virus. also, phylogenetic analysis further confirmed that each of the eight genes of the isolates was closely related to the classical swine h1n1 viruses, especially those isolated in china. ... | 2009 | 19521758 |
| cluster analysis of the origins of the new influenza a(h1n1) virus. | in march and april 2009, a new strain of influenza a(h1n1) virus has been isolated in mexico and the united states. since the initial reports more than 10,000 cases have been reported to the world health organization, all around the world. several hundred isolates have already been sequenced and deposited in public databases. we have studied the genetics of the new strain and identified its closest relatives through a cluster analysis approach. we show that the new virus combines genetic informa ... | 2009 | 19480812 |
| insights from investigating the interaction of oseltamivir (tamiflu) with neuraminidase of the 2009 h1n1 swine flu virus. | the neuraminidase (na) of influenza virus is the target of anti-flu drugs oseltamivir and zanamivir. clinical practices showed that oseltamivir was effective to treat the 2009-h1n1 influenza but failed to the 2006-h5n1 avian influenza. to perform an in-depth analysis on such a drug-resistance problem, the 2009-h1n1-na structure was developed. to compare it with the crystal 2006-h5n1-na structure as well as the 1918 influenza virus h1n1-na structure, the multiple sequential and structural alignme ... | 2009 | 19523442 |
| unraveling the mystery of swine influenza virus. | influenza virus outbreaks occur with regularity, but the severity of outbreaks is not consistent. the recent flu epidemic caused by an h1n1 swine influenza virus presents an opportunity to examine what is known about virulence factors and the spread of infection to better prepare for major influenza outbreaks in the future. | 2009 | 19524497 |
| influenza a (h1n1) infection in pigs. | 2009 | 19525527 | |
| pigs might fly. | 2009 | 19483041 | |
| [what to call it? swine, mexican or american flu?]. | 2009 | 19526981 | |
| [dr. chan, swine flu and the end of the world]. | 2009 | 19526982 | |
| trials and tribulations.....and now swine flu. | 2009 | 19490130 | |
| swine flu, pandemics, and critical care. | 2009 | 19490596 | |
| likelihood that an unsubtypeable influenza a virus result obtained with the luminex xtag respiratory virus panel is indicative of infection with novel a/h1n1 (swine-like) influenza virus. | 2009 | 19494066 | |
| swine influenza: then and now. | 2009 | 19494369 | |
| swine flu - an assessment of the australian response. | swine flu, 2009's influenza pandemic, has been in the spotlight since it began in mexico early in 2009. the global response to swine flu has been forceful in an attempt to prevent a repeat of previous devastating influenza pandemics. outside mexico swine flu has remained for the most part a mild disease, and it may turn out to be no more dangerous than seasonal influenza. however it is crucial that a rapid, effective worldwide response be mounted while the severity of this virus remains unknown. | 2009 | 19534568 |
| genetic and antigenic evolution of swine influenza viruses in europe and evaluation of their zoonotic potential. | swine influenza is a highly contagious respiratory viral infection of pigs that has become enzootic in areas densely populated with pigs. like other influenza a viruses, swine influenza virus (siv) is genetically unstable and able to accumulate antigenic drifts and/or antigenic shifts. the pig is susceptible to both avian and human influenza viruses and can serve as an intermediate host in influenza virus ecology. zoonotic agents may emerge in pigs following the modification of an established sw ... | 2009 | 19497089 |
| origins of the new influenza a(h1n1) virus: time to take action. | to gain insight into the possible origins of the 2009 outbreak of new influenza a(h1n1), we performed two independent analyses of genetic evolution of the new influenza a(h1n1) virus. firstly, protein homology analyses of more than 400 sequences revealed that this virus most likely evolved from recent swine viruses. secondly, phylogenetic analyses of 5,214 protein sequences of influenza a(h1n1) viruses (avian, swine and human) circulating in north america for the last two decades (from 1989 to 2 ... | 2009 | 19497253 |
| epidemiology of new influenza a (h1n1) virus infection, united kingdom, april-june 2009. | following the previous report to eurosurveillance on 14 may 2009, the number of confirmed cases of new influenza a(h1n1) has continued to increase in the united kingdom. by 31 may, uk surveillance activities had detected a total of 252 confirmed cases. seventy (28%) were related to travel to the united states and mexico. there is evidence of spread in households, schools and the community with increases in secondary (n=40), tertiary (n=125) and sporadic (n=13) cases. the new influenza a(h1n1) vi ... | 2009 | 19497255 |
| pandemic or no pandemic: emergence of swine influenza a (h1n1) in 2009. | 2009 | 19539828 | |
| association of tumor necrosis factor-alpha with fever and pulmonary lesion score in pigs experimentally infected with swine influenza virus subtype h1n2. | the relationship between tumor necrosis factor (tnf)-alpha level, body temperature, and pulmonary lesion score was determined in 3-week-old pigs inoculated intranasally with swine influenza virus (siv) subtype h1n2. the expression of tnf-alpha was measured in bronchoalveolar lavage (bal) fluids by enzyme-linked immunosorbent assay and lung tissues by immunohistochemistry. in bal fluid, tnf-alpha concentration was maximal at 1 days post-inoculation (dpi), declined markedly by 3 dpi (p<0.05) and s ... | 2009 | 19498287 |
| 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 |