| swine influenza virus in man. zoonosis or human pandemic? | | 1976 | 59086 |
| swine influenza virus and the recycling of influenza-a viruses in man. | sera collected in 1967 and 1972 from people in the 0-100 age-group showed haemagglutination-inhibition (h.i.) antibody to swine virus a/iowa/15/30 (hsw1n1) in greatest number and with highest titre in people born before 1918. a slight decrease was observed from 1967 to 1972 in the number of sera with antibody to swine virus and in the height of the titres. the recently isolated a/new jersey/10/76 (hsw1n1) virus showed a result comparable to that of the swine/1930 virus in sera of 1972. on the an ... | 1976 | 59252 |
| evaluation of 6-azauridine and 5-iododeoxyuridine in the treatment of experimental viral infections. | the potential antiviral activity of 6-azauridine and 5-iododeoxyuridine was evaluated in a coordinated study at five institutions. experimental models in five species, the mouse, rabbit, swine, cat, and ferret, were established with use of 10 viruses: herpesvirus hominis types 1 and 2, murine cytomegalovirus, vaccinia virus, shope fibroma virus, transmissible gastroenteritis virus, swine influenza virus, feline viral rhinotracheitis virus, feline panleukopenia virus, and ferret distemper virus. ... | 1976 | 180189 |
| investigations on the involvement of swine influenza a virus (hsw1n1) in the influenza outbreak recorded in a town of romania during the 1976--1977 winter season. | seroepidemiological investigations performed with 1,620 serum samples and serodiagnostic tests with 166 paired sera demonstrated that swine influenza virus type a/new jersey 8/76 (hsw1n1) played no role in the epidemiology of human influenza in a large town of romania during 1977. | 1978 | 567886 |
| identification and preliminary antigenic analysis of swine influenza-like viruses isolated during an influenza outbreak at fort dix, new jersey. | the sequence of events and the laboratory procedures that resulted in the identification of swine influenza-like viruses isolated during an influenza outbreak at fort dix, new jersey in january and february of 1976 are described. preliminary antigenic analysis suggested that the isolates from fort dix are closely related to a 1975 isolate of swine influenza virus and distinguishable from earlier swine influenza strains. | 1977 | 606762 |
| antigenic variant of swine influenza virus causing proliferative and necrotizing pneumonia in pigs. | a new antigenic variant of swine influenza virus was isolated from the lungs of pigs experiencing respiratory problems in 7 different swine herds in quebec. pigs of different ages were affected, and the main clinical signs were fever, dyspnea, and abdominal respiration. coughing was not a constant finding of the syndrome. at necropsy, macroscopic lesions included the overall appearance of pale animals, general lymphadenopathy, hepatic congestion, and consolidation of the lungs. histopathologic f ... | 1992 | 1333815 |
| the first isolation of swine h1n1 influenza viruses from pigs in thailand. | two influenza a viruses were isolated from pigs in thailand in january 1988 during the early febrile stage of an influenza-like illness. the isolates contained hemagglutinin and neuraminidase antigens related to those of swine h1n1 influenza virus. this result based on the virus isolation is compatible with the epizootiological evidence that, unlike the human influenza with peak activity in summer (may-july), swine influenza virus is prevalent in the winter season (november-january) in thailand. ... | 1991 | 1648899 |
| outbreaks in quebec pig farms of respiratory and reproductive problems associated with encephalomyocarditis virus. | encephalomyocarditis virus (emcv) was isolated from tissues of aborted fetuses and weaned and suckling piglets from 4 different pig farms in quebec. the farms were experiencing reproductive failure in sows of different parities concomitant to respiratory problems in suckling and postweaning piglets. at necropsy, gross lesions were confined to the lung and consisted of pulmonary congestion and edema of various degrees. lesions of multifocal interstitial to proliferative pneumonia were found in th ... | 1991 | 1662074 |
| laboratory characterization of a swine influenza virus isolated from a fatal case of human influenza. | a swine influenza virus-like type a (h1n1) virus, designated a/wisconsin/3523/88, was isolated in september 1988 from a wisconsin woman who had died with primary viral pneumonia. antigenic analyses with hemagglutinin-specific monoclonal antibodies and postinfection ferret serum indicated that the hemagglutinin of a/wisconsin/3523/88 was antigenically closely related to viruses currently circulating in swine. genetic analysis of the a/wisconsin/3523/88 virus by rna fingerprinting and partial rna ... | 1989 | 2754013 |
| evolutionary pathways of the pa genes of influenza a viruses. | nucleotide sequences of the pa genes of influenza a viruses, isolated from a variety of host species, were analyzed to determine the evolutionary pathways of these genes and the host specificity of the genes. results of maximum parsimony analysis of the nucleotide sequences indicate at least five lineages for the pa genes. those from human strains represent a single lineage, whereas the avian genes appear to have evolved as two lineages--one comprising genes from many kinds of birds (e.g., chick ... | 1989 | 2800339 |
| response of calves to exposure with swine influenza virus. | in calves inoculated with live swine influenza virus (siv) a/sw/il/75 (h1n1) intranasally, siv was isolated for 7 days, and respiratory tract disease was observed. antibody was detected in serum of inoculated calves from postinoculation day 9, and virus-neutralization antibody was demonstrated on postinoculation days 14 and 21. the primary response was low, but readily differentiated from the secondary response after calves were challenge exposed with homologous siv. pneumonic lesions were obser ... | 1987 | 2820279 |
| human infection with swine influenza virus--wisconsin. | | 1988 | 2846999 |
| [3 cases of isolating the influenza a virus with human hemagglutinin hsw1 in 1983 in alma-ata]. | in the interepidemic period of late 1983 in alma-ata, influenza viruses with hemagglutinin of the swine subtype and neuraminidases n1 and n2 were isolated from humans. one of the strains, a/alma-ata/1044/83 (hsw1n1), was isolated from the lungs of a man of 65 with the diagnosis of influenza and disseminated intravascular syndrome who had had communal and occupational contacts with swine. in paired sera of a sick child, and in seroepidemiological screening for influenza antibodies to swine influe ... | 1985 | 3000080 |
| [the persistence of activity of h1n1 (swine) influenza virus in pig breeding units during non-epidemic phases]. | a study is carried on in a group of 16 commercial breeding-finishing units in brittany (france). the aim of this study is to try to reveal the persistence of activity of the influenza virus within these intensive units after an acute epizootic. in each farm two batches of pigs are selected, individually identified and followed from suckling period to slaughter. serological controls are conducted every month on the same pigs. both influenza and aujeszky's disease antibodies are apprehended. furth ... | 1985 | 3004802 |
| [cloning and sequencing of the hemagglutinin gene of swine influenza virus]. | | 1985 | 3837545 |
| leads from the mmwr. human infection with swine influenza virus--wisconsin. | | 1988 | 2846902 |
| antigenic stability of h3 influenza viruses in the domestic duck population of southern china. | an antigenic analysis was carried out on 145 duck influenza virus isolates of the h3 haemagglutinin subtype obtained over five years continuous surveillance from the region of southern china, a hypothetical influenza epicentre. this was done using a panel of twelve monoclonal antibodies raised to an early human strain of the h3 subtype. we demonstrate the existence of an extensive range of antigenic profiles, broadly similar but not identical to the human h3 strain, which persisted over the five ... | 1990 | 2222188 |
| fatal swine influenza pneumonia during late pregnancy. | serious morbidity or death from swine influenza infection is unusual in the immunocompetent host. we present a fatal case of pneumonia caused by this virus in a previously healthy 32-year-old woman during her third trimester of pregnancy, and review all published case reports of swine influenza in united states civilians. pregnancy may be a predisposing factor to fulminant infection with swine influenza virus. | 1990 | 2153372 |
| conjunctivitis associated with a mycoplasma-like organism in swine. | a midwestern producer reported high incidence of conjunctivitis and keratoconjunctivitis in a herd of crossbred finishing swine. complete necropsy was performed on 3 pigs with bilateral mucopurulent conjunctivitis and chemosis; other gross lesions were not seen. mycoplasma sp was isolated from conjunctival swab specimens obtained from 1 pig; small numbers of streptococci and coagulase-negative staphylococci were isolated from conjunctival swab specimens from all 3 pigs. neither swine influenza v ... | 1991 | 2010341 |
| swine influenza virus infections. transmission from ill pigs to humans at a wisconsin agricultural fair and subsequent probable person-to-person transmission. | in september 1988, a previously healthy 32-year-old pregnant woman was hospitalized for pneumonia and died 8 days later. the only pathogen detected was an influenza virus antigenically related to the swine influenza virus (siv). four days before illness onset, the patient visited a county fair swine exhibition where there was widespread influenzalike illness among the swine. to detect other persons who were possibly infected by contact with the ill swine, we measured serum siv hemagglutination-i ... | 1991 | 1845913 |
| hemagglutinin mutations related to antigenic variation in h1 swine influenza viruses. | the hemagglutinin (ha) of a recent swine influenza virus, a/sw/in/1726/88 (h1n1), was shown previously to have four antigenic sites, as determined from analysis of monoclonal antibody (mab)-selected escape mutants. to define the ha mutations related to these antigenic sites, we cloned and sequenced the ha genes amplified by polymerase chain reaction of parent virus and mab-selected escape mutants. the genetic data indicated the presence of four amino acid changes. after alignment with the three- ... | 1992 | 1731091 |
| prevalence of pseudorabies virus infection and associated infections in six large swine herds in illinois. | sera were collected from 6 large farrow-to-finish swine herds infected with pseudorabies virus (prv) in illinois. all herds were participating in the large herd cleanup study, a usda-initiated project to evaluate the feasibility of eradicating pseudorabies from large farms (greater than 400 sows) by use of a combination of vaccination and management changes. herd size ranged between 425 and 1,500 breeding females. between april and july 1990, sera for measurement of prv antibodies were obtained ... | 1991 | 1651912 |
| interspecies transmission and reassortment of influenza a viruses in pigs and turkeys in the united states. | genetic reassortment between influenza a viruses in humans and in animals and birds has been implicated in the appearance of new pandemics of human influenza. to determine whether such reassortment has occurred in the united states, the authors compared the genetic origins of gene segments of 73 swine influenza virus isolates (1976-1990), representing 11 states, and 11 turkey virus isolates (1980-1989), representing eight states. the host origin of gene segments encoding the internal proteins of ... | 1992 | 1415168 |
| pathogenicity of concurrent infection of pigs with porcine respiratory coronavirus and swine influenza virus. | combinations of porcine respiratory coronavirus (prcv) and either of two swine influenza viruses (h1n1 or h3n2) were administered intranasally and by aerosol to six- to eight-week-old specific pathogen-free pigs. the clinical responses, gross respiratory lesions and growth performances of these pigs were studied and compared with those of single (prcv, h1n1 or h3n2) and mock-infected animals. prcv infection caused fever, growth retardation and lung lesions, but no respiratory symptoms. infection ... | 1992 | 1334565 |
| antigenicity of inactivated swine influenza virus concentrated by centrifugation. | swine influenza virus grown in fertile chicken eggs was inactivated with a 1:4000 dilution of formalin for three days. centrifugation at 47,000 g for 1-3 hours concentrated the viral particles. reconstitution to 1/10 the original volume for use as a vaccine resulted in a product having an ha titer of 1:64 to 1:512. two doses of 4 ml given three weeks apart resulted in a serologic response in three of six gilts of breeding age. experimental challenge of two vaccinated and two control gilts to swi ... | 1976 | 1257594 |
| local immunity in the pig respiratory tract. i. -- cellular and humoral immune responses following swine influenza infection. | by serial lung washings on living pigs, kinetics of humoral and cellular local immune responses have been studied following intranasal inoculation of swine influenza virus. local and serum antibodies appeared 8 days post-infection (p.i.) and reached a maximal titer 2 weeks p.i. antibody titer decreased faster in lung secretions than in serum. local and systemic cell-mediated immune responses were detected, by in vitro transformation tests, during the second week p.i. | 1977 | 907269 |
| sero-epizootiological study on swine influenza in a prefecture of japan. | a total of 1799 swine sera collected in toyama prefecture in the central part of japan during the years 1978-82 were tested for antibody against swine influenza virus (siv), a/new jersey/8/76 (h1n1). a high prevalence of antibody was observed in the years after the severe epizootic of si, 34.5% in 1979 and 51.7% in 1982. in other years, the percentages of positive sera were low and ranged from 1.7 to 12.4%. regional variations were seen in relation to a small scale epizootic. no antibody to siv ... | 1983 | 6306099 |
| local immunity in the pig respiratory tract. ii. -- relationship of serum and local antibodies. | antibody passage from blood to respiratory secretions was studied on pigs. the animals were passively immunized and have a high anti-hog cholera serum antibody titer. with normal animals as with swine influenza animals, no serum antibody could be recovered neither in buccopharyngeal secretions nor in lung washings: it seems that in such conditions no detectable transudation occurs from blood to local secretions. following intranasal inoculation of swine influenza virus or intramuscular injection ... | 1977 | 907266 |
| lack of significant person-to-person spread of swine influenza-like virus following fatal infection in an immunocompromised child. | in february 1982, a four-year-old nevada girl with acute lymphoblastic leukemia in remission was hospitalized with fulminant pneumonia and died eight days later at a hospital in california. an influenza virus was the only pathogen detected, and was present in both antemortem and postmortem specimens. the virus was closely related antigenically to a/new jersey/8/76 (h1n1) and had a genome very similar to a contemporary enzootic swine influenza virus. the patient had had no known contact with swin ... | 1984 | 6320637 |
| antibody formation in laboratory animals after parenteral application of a/swine influenza virus. | antigenicity of swine influenza viruses, ann arbor/31 and recombinant x-53, was compared on the different animal species. the serological investigations of animals infected with live or immunized with the inactivated virus, demonstrated a close antigenic relationship between the h and n antigens of both viruses. for inactivated vaccine preparation it was recommended, on the basis of our results, to use ann arbor virus instead of virus x-53. | 1977 | 604122 |
| guillain-barré syndrome: the swine influenza virus vaccine incident in the united states of america, 1976-77: preliminary communication. | | 1979 | 552571 |
| swine influenza virus vaccine: potentiation of antibody responses in rhesus monkeys. | polyriboinosinic-polyribocytidylic acid stabilized with poly-l-lysine and carboxymethylcellulose [poly(iclc)] enhances the antibody response in rhesus monkeys immunized with swine influenza virus subunit vaccine. monkeys given the vaccine-adjuvant combination had earlier and significantly (p less than .05) higher titers by 14 days compared to those that received vaccine alone. the potentiation of the antibody response of young monkeys given a split-virus vaccine in combination with poly(iclc) su ... | 1977 | 408923 |
| [immune response of pigs to aujeszky disease virus and swine influenza virus]. | explored was the possibility of simultaneous vaccination of pigs against the aujeszky's disease virus and the swine influenza virus. used were strain mk-25 against the former and strain 3sb against the latter. it was found that at the simultaneous subcutaneous or oral treatment with the two antigens equally effective immunity was built as in the case of vaccination with each one of them used alone. no antagonism was established between the two antigens during the time of immunity building in the ... | 1978 | 214936 |
| serologic and epidemiologic evidence of infection in turkeys with an agent related to the swine influenza virus. | | 1981 | 6791627 |
| multiple-cloning-site plasmids for the rapid construction of recombinant poxviruses. | plasmid vectors containing multiple cloning sites suitable for the rapid insertion of protein-coding sequences into poxviruses have been constructed. they are based on puc plasmids and carry the thymidine kinase (tk) gene of vaccinia virus interrupted by a vaccinia virus promoter. six unique restriction enzyme sites (bamhi, sali/hincii, psti, hindiii, ecori), located within 40 bp of vaccinia virus promoters transposed from the hindiii-f or hindiii-c fragment of the vaccinia virus genome, allow r ... | 1985 | 4029620 |
| prevalence of hemagglutination inhibition antibody to current strains of the h3n2 and h1n1 subtypes of influenza a virus in sera collected from the elderly in 1976. | sera were collected in 1976 from 182 individuals born between 1876-1935, who included patients in a large local nursing home in orange county, california, and patients and staff at the university of california, irvine medical center. sera were treated with receptor-destroying enzyme and assayed for hemagglutination inhibition (hi) antibody to recent strains of influenza a virus. the antigens tested were: a/victoria/3/76 and a/texas/1/77 for subtype h3n2; a/new jersey/8/76, a/x53 and a/swine/1976 ... | 1982 | 7072705 |
| statistical analysis of results of a survey on antibody against swine influenza virus in pigs by single radial hemolysis and hemagglutination-inhibition tests. | | 1982 | 7078660 |
| detection of influenza a viruses and influenza epidemics in wild pelagic birds by sentinels and population studies. | field experiments with domestic ducks as sentinels and virological and serological population observations on wild pelagic birds on a seabird-breeding island in the baltic sea and on rivers and lakes near berlin were conducted to detect the influenza a virus circulation and epidemics in wild pelagic bird populations. influenza a virus isolates were detected in tracheal and cloacal swabs from sentinel ducks and from healthy pelagic birds. influenza a virus epidemics with different subtypes in an ... | 1982 | 7170852 |
| genetic variation in swine influenza virus a isolate associated with proliferative and necrotizing pneumonia in pigs. | a new antigenic variant of h1n1 swine influenza virus a (sw/qc/5393/91 [qc/91]) has been found to be associated with porcine proliferative and necrotizing pneumonia. analysis of its genomic rna by t1 oligonucleotide mapping revealed that considerable genomic divergence exists between qc/91 and the swine influenza viruses currently circulating in north american swine herds. analysis of the nucleotide sequence of the ha1 region of the hemagglutinin rna of qc/91, in comparison with those of most co ... | 1994 | 7545918 |
| inactivation of viruses in liquid manure. | the stability of some viruses and methods of virus inactivation in liquid manure are reviewed. the authors discuss experimental data on the stability of foot and mouth disease virus, classical swine fever virus, aujeszky's disease virus, african swine fever virus, swine influenza virus, porcine paramyxovirus, bovine virus diarrhoea virus and transmissible gastroenteritis of pigs virus. recommendations and practical advice are given for the choice and application of chemical disinfectants for slu ... | 1995 | 7579641 |
| responses of cattle, sheep and poultry to a recombinant vaccinia virus expressing a swine influenza haemagglutinin. | groups of cattle, sheep and poultry were inoculated with a recombinant vaccinia virus expressing the haemagglutinin of the swine influenza virus a/nj/11/76. no adverse clinical responses were recorded and none of the animals developed a viraemia when inoculated with the recombinant or wild-type vaccinia virus. recombinant virus reisolated from lesions in cattle was stable, maintaining its thymidine kinase negative phenotype and ability to express the swine influenza haemagglutinin. antibodies to ... | 1986 | 3764100 |
| epidemiological study of swine influenza virus as a component of the respiratory disease complex of feeder calves. | a survey of 177 paired calf sera collected during the years 1978-1981 showed that 3.4% of the calves had prior experience with swine influenza virus. six calves positive by the single radial hemolysis test (srh) were also positive by the virus neutralization test (vn) in chicken embryos, and one calf reacted with all three tests (hemagglutination-inhibition (hi), srh, and vn). the srh and hi tests available cannot adequately provide the information necessary in a survey of this sort. the hi test ... | 1986 | 3517990 |
| origin of the hemagglutinin gene of h3n2 influenza viruses from pigs in china. | influenza viruses of the h3n2 subtype similar to aichi/2/68 and victoria/3/75 persist in pigs many years after their antigenic counterparts have disappeared from humans (shortridge et al. (1977). science 19, 1454-1455). to provide information on the mechanism of conservation of these influenza viruses in pigs, the hemagglutinin (ha) of four isolates from swine derived from taiwan and southern china were analyzed antigenically and genetically. the reactivity pattern of these viruses with a panel ... | 1988 | 3336940 |
| immunohistochemical detection of swine influenza virus and porcine reproductive and respiratory syndrome virus in porcine proliferative and necrotizing pneumonia cases from québec. | | 1994 | 7954227 |
| a new concept of the epidemic process of influenza a virus. | influenza a virus was discovered in 1933, and since then four major variants have caused all the epidemics of human influenza a. each had an era of solo world prevalence until 1977 as follows: h0n1 (old style) strains until 1946, h1n1 (old style) strains until 1957, h2n2 strains until 1968, then h3n2 strains, which were joined in 1977 by a renewed prevalence of h1n1 (old style) strains. serological studies show that h2n2 strains probably had had a previous era of world prevalence during the last ... | 1987 | 3301379 |
| evolution to predominance of swine influenza virus hemagglutinin mutants of predictable phenotype during single infections of the natural host. | l and h2 mutants of the a/nj/11/76 h1n1 strain of swine influenza virus differ by having either a lysine or a glutamic acid at position 153 of the hemagglutinin glycoprotein of the virus. in two separate experiments, experimental infection of swine with various doses of the h2 mutant resulted in the emergence in 11 of 20 animals of virus with the l phenotype. all evidence indicates that the h2----l mutation, selection, and evolution to predominance occurred within the 7-day span of individual in ... | 1988 | 3186713 |
| genetic relatedness between influenza a (h1n1) viruses isolated from humans and pigs. | complete nucleotide sequences were obtained from the nucleoprotein genes of three influenza a viruses and partial nucleotide sequences were obtained from the polymerase, neuraminidase, matrix, and non-structural protein genes of four influenza a viruses that had been isolated between 1931 and 1939 from clinically sick pigs in the united states or europe. a phylogenetic analysis of the open reading frames of nine nucleoprotein genes showed that the u.s. swine influenza virus isolates from 1931 an ... | 1994 | 8046416 |
| an influenza a (h1n1) virus, closely related to swine influenza virus, responsible for a fatal case of human influenza. | in july 1991, an influenza a virus, designated a/maryland/12/91 (a/md), was isolated from the bronchial secretions of a 27-year-old animal caretaker. he had been admitted to the hospital with bilateral pneumonia and died of acute respiratory distress syndrome 13 days later. antigenic analyses with postinfection ferret antisera and monoclonal antibodies to recent h1 swine hemagglutinins indicated that the hemagglutinin of this virus was antigenically related to, but distinguishable from, those of ... | 1994 | 8138990 |
| hemagglutinin polymorphism as the basis for low- and high-yield phenotypes of swine influenza virus. | single amino acid substitutions at the rim of the receptor binding site of the hemagglutinin molecule of swine influenza virus markedly influence the replicative capacity of the virus in chicken embryos, madin-darby canine kidney cells (mdck), and swine as well as its antigenic phenotype. mutants of low-yield (l) phenotype replicate poorly in chicken embryos and produce small plaques in mdck cells but are highly infective for swine. such mutants have lysine at position 153 and glycine at positio ... | 1988 | 3174662 |
| a single radial hemolysis technique for the measurement of influenza virus antibody in cattle serum. | a single radial hemolysis technique (srh) was used to measure swine influenza virus antibody in calf serum. heating at 56 c for 60 minutes was necessary to prevent non-specific hemolysis. a significant association was found between the mean diameter of the hemolysis zone obtained with the srh test and the geometric mean hemagglutination inhibition (hi) titer in sera of 5 calves inoculated with the virus after treatment with periodate (r = 0.92, p 0.01) and receptor destroying enzyme (r = 0.94, p ... | 1986 | 3008275 |
| ultrastructural morphometric investigation of early lesions in the pulmonary alveolar region of pigs during experimental swine influenza infection. | experimental infection of specific-pathogen-free pigs with swine influenza virus by the intratracheal route resulted in a severe respiratory disease that closely resembled natural swine influenza in clinical course and pathologic lesions. alveolar epithelial necrosis with sloughing of necrotic cells occurred from 24 to 96 hours after inoculation (p.i.) and was associated with alveolar edema and diffuse interstitial pneumonitis. the latter, initially of neutrophilic character, became histiocytic ... | 1986 | 3006499 |
| swine interferon. i. induction in porcine cell cultures with viral and synthetic inducers. | the production of interferon by porcine kidney (pk(15)) cell culture in response to viral and synthetic inducers was studied. the inducers used included a synthetic double-stranded polyribonucleotide, polyriboinosinic-polyribocytidylic acid (poly i:c), swine influenza virus and three strains of pseudorabies virus. following exposure to these inducers cell culture fluids were examined for interferon by the plaque-reduction method. the poly i:c and the swine influenza virus induced production of i ... | 1972 | 4340345 |
| experimental infection of weanling pigs with a-swine influenza virus. i. epidemiology and serological response. | naturally occurring swine influenza is caused by a strain of virus closely related to influenza strains isolated from man in 1918 and later. information is lacking on certain aspects of the epidemiology of swine influenza that, if obtained, might shed some light on the epidemiology of human influenza, particularly with respect to inter-epidemic reservoirs and shedders of the virus. in a first series of experiments undertaken by the authors pigs were experimentally infected intranasally with swin ... | 1970 | 5311061 |
| swine influenza virus strains recognize sialylsugar chains containing the molecular species of sialic acid predominantly present in the swine tracheal epithelium. | we determined the ratio of n-glycolylneuraminic acid (neu5gc) to n-acetylneuraminic acid (neu5ac) in swine respiratory epithelia by fluorometric high-performance liquid chromatography, and examined the binding specificity of swine influenza virus strains for gangliosides containing different molecular species of sialic acid (neu5ac and neu5gc), and for bovine erythrocyte sialoglycoprotein 2 (gp-2) containing neu5gc as its predominate sialic acid (96% of total sialic acids). the presence of neu5g ... | 1997 | 9119062 |
| a monoclonal-antibody-based immunohistochemical method for the detection of swine influenza virus in formalin-fixed, paraffin-embedded tissues. | | 1997 | 9211240 |
| swine influenza virus vaccine incident. | | 1984 | 6086921 |
| sporadic occurrence of zoonotic swine influenza virus infections. | two infections by swine influenza virus, antigenically similar to a/new jersey/76 (h1n1) virus, were detected during community epidemics with other influenza viruses. the swinelike viruses were obtained during virological surveillance of acute respiratory illnesses, and the clinical symptoms of these two patients were similar to those caused by other respiratory viruses. both patients reported contact with swine a few days before onset of illness, but in one case it was brief. serological studie ... | 1984 | 6092435 |
| the possible origin h1n1 (hsw1n1) virus in the swine population of japan and antigenic analysis of the isolates. | virus isolation and serological studies on swine sera collected during 1973 to 1978 showed that h1n1 (hsw1n1) influenza viruses first appeared in the swine population of japan about may 1977. with the exception of one strain, both haemagglutinin and neuraminidase subunits of all the h1n1 viruses isolated from swine in japan and from pigs imported from north america were antigenically indistinguishable from those of a/nj/8/76 virus, suggesting the introduction of swine influenza virus into japan ... | 1982 | 6182266 |
| monoclonal antibodies to the hemagglutinin sa antigenic site of a/pr/8/34 influenza virus distinguish biologic mutants of swine influenza virus. | the dimorphic l and h hemagglutinin mutants of a/nj/11/76(h1n1) (swine) influenza virus differ pleiotropically in their replication and virulence characteristics and in their antigenicity. l mutants replicate less well in chicken embryos and madin-darby canine kidney cells and are more infective for swine than are h mutants. l and h mutants are not antigenically distinguishable in cross-neutralization tests with homotypic antisera, but they can be identified with certain heterotypic heterogeneou ... | 1983 | 6194531 |
| isolation of a recombinant influenza virus (hsw 1 n2) from swine in japan. | outbreaks of swine influenza were first observed in japan in 1978. a number of influenza viruses were isolated from diseased swine. almost all viruses isolated were swine influenza virus (hsw 1 n1) but two viruses isolated from the nasal swabs of swine showing clinical signs of influenza in the kanagawa prefecture were characterized antigenically as hsw 1 n2. analysis of swine sera showed that influenza virus hsw 1 n2 was epidemic in the farm from which the virus had been isolated. the new virus ... | 1980 | 6255900 |
| serosurvey of selected viral and bacterial diseases in wild swine from oklahoma. | blood samples collected from 120 wild swine (sus scrofa) in thirteen oklahoma (usa) counties during 1996 were tested for antibodies against six viral and two bacterial diseases. no antibodies to swine brucellosis, pseudorabies, transmissible gastroenteritis, and vesicular stomatitis were detected. antibody titers to one or more leptospiral serovars were found in 44% of the samples, the two most frequent serovars being leptospira interrogans serovars bratislava (29%) and pomona (27%). antibody ag ... | 1998 | 9813859 |
| swine influenza virus in swine and man in illinois. | serum samples from 2,091 persons from illinois populations of swine abattoir employees, 4-h club youths and their advisors, veterinary medical students, pork producers, and veterinarians were tested for hemagglutination-inhibition (hi) antibodies to a/swine/ill./63. a total of 231 positive reactions of 1:20 or above were found (11%). the highest prevalence of antibody was found in veterinarians, followed by pork producers and future swine abattoir employees. age-adjusted reactor rates were highe ... | 1981 | 6260919 |
| an epidemic of swine influenza in japan. | in a serological survey of pigs in japan haemagglutination inhibition (hi) antibody to swine influenza virus (hsw1n1) was first detected in 721 of 3313 (21.1 per cent) sera in 1977 and 1578 of 4946 (32.1 per cent) in 1978. the virus was prevalent in all districts of japan but to a different extent. in contrast to the high incidence of antibody, there were few cases of infection with clinical signs and only 13 outbreaks of swine influenza were recognised in japan from 1978 to 1979. thirty-seven i ... | 1981 | 6281867 |
| failure of swine influenza virus to cause transplacental infection of porcine fetuses. | | 1982 | 6283964 |
| zoonotic studies on influenza in pigs and birds, india, 1980-81. | five hundred and twenty pig sera collected from pune, maharashtra state, india during 1980 were examined in haemagglutination inhibition (hi) tests to determine the antibody prevalence to nine human influenza virus strains covering the subtypes a(hon1), a(h1n1), a(h2n2), a(h3n2), type b and one swine influenza virus strain a(hsw1n1). this study indicated considerable prevalence of antibodies to the four h3n2 strains isolated from 1973 onwards, particularly to the two recent h3n2 strains, limited ... | 1983 | 6315619 |
| serological studies in austrian fattening pigs with respiratory disorders. | serum samples of 253 fattening pigs out of 44 different herds with respiratory signs were examined for antibodies to aujeszky's disease virus by elisa, swine influenza virus (hi test), porcine respiratory coronavirus (elisa) and porcine reproductive and respiratory syndrome virus (ipma). one single case of aujeszky's disease was detected at slaughter. on the other hand 24.5% of the animals proved to be positive for swine influenza, although no vaccine is licensed in austria, and 63.6% reacted po ... | 1994 | 7810433 |
| comparison of serologic testing and slaughter evaluation for assessing the effects of subclinical infection on growth in pigs. | to compare serologic testing with slaughter evaluation in assessing effects of subclinical infection on average daily weight gain (adg) in pigs. | 2000 | 10997163 |
| antigenic characterization of an h3n2 swine influenza virus isolated from pigs with proliferative and necrotizing pneumonia in quebec. | a new strain of swine influenza a virus, designated a/swine/saint-hyacinthe/150/90 has been isolated from pigs with severe proliferative and necrotizing pneumonia in quebec. the antigenic characterization of the hemagglutinin was performed by hemagglutination inhibition test, immunoblot and indirect immunoprecipitation using polyclonal antisera. only the last test was able to detect an antigenic relationship between the hemagglutinin of this isolate and an h3 subtype influenza virus. the immunop ... | 1994 | 7889461 |
| recent h3n2 swine influenza virus with haemagglutinin and nucleoprotein genes similar to 1975 human strains. | of the four pandemic strains of human influenza a virus observed this century, the 1977 virus strain was very similar in all genes to a 1950 isolate. since mammalian influenza a viruses change annually by genetic drift, this reappearance could only be attributed at that time to conservation of the virus in a frozen state. we report here the isolation of swine influenza a viruses with haemagglutinin and nucleoprotein genes which are virtually identical to those of the human virus that circulated ... | 1995 | 7897358 |
| interaction between mycoplasma hyopneumoniae and swine influenza virus. | an experimental respiratory model was used to investigate the interaction between mycoplasma hyopneumoniae and swine influenza virus (siv) in the induction of pneumonia in susceptible swine. previous studies demonstrated that m. hyopneumoniae, which produces a chronic bronchopneumonia in swine, potentiates a viral pneumonia induced by the porcine reproductive and respiratory syndrome virus (prrsv). in this study, pigs were inoculated with m. hyopneumoniae 21 days prior to inoculation with siv. c ... | 2001 | 11427564 |
| x-ray structures of h5 avian and h9 swine influenza virus hemagglutinins bound to avian and human receptor analogs. | the three-dimensional structures of avian h5 and swine h9 influenza hemagglutinins (has) from viruses closely related to those that caused outbreaks of human disease in hong kong in 1997 and 1999 were determined bound to avian and human cell receptor analogs. emerging influenza pandemics have been accompanied by the evolution of receptor-binding specificity from the preference of avian viruses for sialic acid receptors in alpha2,3 linkage to the preference of human viruses for alpha2,6 linkages. ... | 2001 | 11562490 |
| use of polymerase chain reaction to detect swine influenza virus in nasal swab specimens. | rapid and accurate detection of a virus in a population is a critical factor in the eventual treatment and/or control of the virus. in this study, we examined use of the polymerase chain reaction (pcr) to detect swine influenza virus in nasal swab specimens from infected pigs. this approach was first standardized, using viral rna purified by guanidinium/phenol-chloroform extraction and placed in the same transport medium as the swabs. by using highly conserved primers for the swine h1 hemaggluti ... | 1994 | 7978634 |
| effect of sequential porcine reproductive and respiratory syndrome and swine influenza on the growth and performance of finishing pigs. | sows and gilts on a breeding and finishing unit seroconverted to porcine reproductive and respiratory syndrome (prrs) virus between february and march 1992. the signs of the disease progressed through the breeding herd to the piglets, weaners, growers and finally the finishing pigs. forty-eight finishing pigs, on a nutritional experiment in which the individual pigs' food intake was recorded daily, showed signs of prrs and later of swine influenza virus infection. blood samples collected at slau ... | 1994 | 7998380 |
| antigenic and genetic analysis of a recently isolated h1n1 swine influenza virus. | hemagglutinins (ha) of h1n1 swine influenza viruses isolated in the united states have remained antigenically and genetically conserved for many years. in contrast to such conservation, the ha of a/swine/nebraska/1/92 (sw/neb) could readily be distinguished from those of contemporary porcine viruses. twenty-eight amino acid mutations differentiated the ha of sw/neb and a/swine/indiana/1726/88, the most recent h1n1 swine influenza virus for which ha sequence data were available. among these diffe ... | 1993 | 8250388 |
| large outbreak of swine influenza in southern japan caused by reassortant (h1n2) influenza viruses: its epizootic background and characterization of the causative viruses. | in the winter of 1989 and the spring of 1990, there were large outbreaks of respiratory disease in two swine herds in nagasaki prefecture, southern japan. serological surveillance indicated that the majority of swine possessed antibodies to swine influenza virus h1 haemagglutinin and neuraminidase of early h3n2 influenza virus strains. eight viruses were isolated from swine that showed typical clinical symptoms of influenza. the haemagglutinin and neuraminidase of these isolates were closely rel ... | 1996 | 8760422 |
| evaluation of a protective immunity induced by an inactivated influenza h3n2 vaccine after an intratracheal challenge of pigs. | a challenge study was conducted to evaluate the safety and efficacy of an inactivated influenza h3n2 virus vaccine combined with quil a/alhydrogel mixture under controlled conditions in piglets. twenty-four piglets from 12 sows were allocated to 2 groups; injected intramuscularly with 2 doses of the tested vaccine or with pbs at 2 wk intervals and challenged intratracheally with 105tcid50 of the h3n2 swine influenza virus 6 d after the 2nd immunization. clinical and virological parameters were r ... | 1996 | 8904668 |
| transmission of swine influenza virus to humans after exposure to experimentally infected pigs. | two people developed symptoms of influenza 36 h after collecting nasal swabs from pigs experimentally infected with a/sw/in/1726/88 (sw/in). pharyngeal swabs from these persons tested positive for influenza virus rna 8 days after infection. analysis of hemi-nested polymerase chain reaction (pcr) products indicated that the hemagglutinin (ha) segments of the isolates were genetically related to the ha of sw/in. four influenza a virus isolates (a/wi/4754/94, a/wi/4756/94, a/wi/4758/94, a/wi/4760/9 ... | 1997 | 8985190 |
| dual infections of feeder pigs with porcine reproductive and respiratory syndrome virus followed by porcine respiratory coronavirus or swine influenza virus: a clinical and virological study. | dual infections of pigs with porcine reproductive and respiratory syndrome virus (prrsv) followed by a second common respiratory virus, either porcine respiratory coronavirus (prcv) or swine influenza virus (siv), were studied. the aim was to determine if dual infections, as compared to single virus infections, result in enhanced clinical manifestations. it was also examined if prrsv replication affects replication of prcv or siv in the respiratory tract. groups of conventional 10 week old pigs ... | 1996 | 9054128 |
| immunization of pigs with a particle-mediated dna vaccine to influenza a virus protects against challenge with homologous virus. | particle-mediated delivery of a dna expression vector encoding the hemagglutinin (ha) of an h1n1 influenza virus (a/swine/indiana/1726/88) to porcine epidermis elicits a humoral immune response and accelerates the clearance of virus in pigs following a homotypic challenge. mucosal administration of the ha expression plasmid elicits an immune response that is qualitatively different than that elicited by the epidermal vaccination in terms of inhibition of the initial virus infection. in contrast, ... | 1998 | 9445052 |
| fatal case of swine influenza virus in an immunocompetent host. | swine influenza virus (siv), a common zoonotic infection, affects swine, particularly during late autumn and winter. transmission of siv from pigs to humans has been reported occasionally; most cases are mild infections and rarely lead to death. herein we describe an immunocompetent woman in whom the adult respiratory distress syndrome developed; she died of a fulminant course of swine influenza. the documented pathogen was the h1n1 strain of siv. to our knowledge, only four other deaths in immu ... | 1998 | 9511782 |
| differences in the biological phenotype of low-yielding (l) and high-yielding (h) variants of swine influenza virus a/nj/11/76 are associated with their different receptor-binding activity. | low- (l) and high-yielding (h) variants of a/sw/nj/11/76 influenza virus were compared for their growth properties in embryonated chicken eggs and mdck cells and for their binding affinity for the membrane fractions prepared from cells of the chicken embryo allantoic membrane. mdck, and swine tracheal cells, as well as for soluble sialic acid containing macromolecules and monovalent sialosides. we have shown, that during infection in mdck cells and in eggs, the progeny of the l variant remain pr ... | 1998 | 9705915 |
| prevalence of swine influenza virus subtypes on swine farms in the united states. | serologic and virologic prevalence of infection with different swine influenza virus (siv) subtypes was investigated using swine sera, nasal swabs and lung samples that had been submitted for a diagnosis to the minnesota veterinary diagnostic laboratory. a total of 111,418 pig sera were tested for siv antibody between 1998 and 2000, and 25,348 sera (22.8%) were found to be positive by the hemagglutination inhibition (hi) test. of the positive samples, 16,807 (66.7%) and 8,541 (33.7%) had antibod ... | 2002 | 12111430 |
| in vivo gene transfer to skin and wound by microseeding. | gene transfer to skin has many potential applications but lacks a safe, practical delivery method. this report presents a new technique, microseeding, for in vivo gene transfer to skin and wounds and for dna-mediated vaccination. the plasmid dna solution was delivered directly to the target cells of the skin by a set of oscillating solid microneedles driven by a modified tattooing device. | 1998 | 9733623 |
| serologic evidence of h1 swine influenza virus infection in swine farm residents and employees. | we evaluated seropositivity to swine and human h1 influenza viruses in 74 swine farm owners, employees, their family members, and veterinarians in rural south-central wisconsin, compared with 114 urban milwaukee, wisconsin, residents. the number of swine farm participants with positive serum hemagglutination-inhibition (hi) antibody titers > or = 40 to swine influenza viruses (17/74) was significantly higher (p<0.001) than the number of seropositive urban control samples (1/114). the geometric m ... | 2002 | 12141967 |
| continued circulation of reassortant h1n2 influenza viruses in pigs in japan. | in 1991 and 1992, h1n2 influenza a viruses were isolated from the lungs of pigs with overt signs of respiratory disease at farms in the chiba and kanagawa prefectures of japan. to determine the genetic origin of these isolates, we phylogenetically analyzed partial nucleotide sequences of their genes. the results indicate that influenza viruses possessing the n2 of human influenza virus and seven other gene segments of classical h1n1 swine influenza virus, which were first isolated in 1980, have ... | 1998 | 9787660 |
| antibodies to selected viral and bacterial pathogens in european wild boars from southcentral spain. | serum samples from 78 european wild boars (sus scrofa) harvested during the 1999-2000 hunting season were tested for antibodies to brucella spp., classical swine fever virus, erysipelothrix rhusiopathiae, haemophilus parasuis, leptospira interrogans serovar pomona, mycoplasma hyopneumoniae, pseudorabies virus (prv), porcine parvovirus (ppv), porcine reproductive and respiratory syndrome virus, salmonella serogroups b, c, and d, streptococcus suis, and swine influenza virus (siv) serotypes h1n1 a ... | 2002 | 12238391 |
| case-control study on the association of porcine circovirus type 2 and other swine viral pathogens with postweaning multisystemic wasting syndrome. | a field-based case-control study was conducted to assess the strength of association of porcine circovirus type 2 (pcv2) and some major swine viruses with postweaning multisystemic wasting syndrome (pmws). cases were defined as individual pigs with a clinical history of progressive weight loss and histopathological lesions characteristic of pmws. controls were pigs without clinical signs and histopathological lesions typical of pmws. a total of 31 cases and 56 controls was identified from diagno ... | 2002 | 12423025 |
| differential production of proinflammatory cytokines in the pig lung during different respiratory virus infections: correlations with pathogenicity. | the acute stages of infection with swine influenza virus (siv), porcine respiratory coronavirus (prcv) and porcine reproductive-respiratory syndrome virus (prrsv) were shown to differ in terms of clinical and lung inflammatory effects and proinflammatory cytokine profiles in bronchoalveolar lavage (bal) fluids. caesarian-derived colostrum-deprived pigs were inoculated intratracheally with one of the three viruses. siv infection was followed within 1 day post inoculation (d pi) by characteristic ... | 1999 | 10425240 |
| isolation of viruses antigenically related to the swine influenza virus from an outbreak of respiratory disease in turkey farms in israel. | | 1984 | 6328732 |
| genetic relatedness between a/swine/iowa/15/30(h1n1) and human influenza viruses. | the nucleotide sequences of the m and ns1 genes of influenza virus a/swine/iowa/15/30 (a/sw/iw/30)(h1n1) were determined with cloned dnas and compared with reported sequences of human and avian influenza viruses. a/sw/iw/30 virus was found to be closely similar to a/pr/8/34(h1n1) virus in the nucleotide sequences of the m and ns1 genes, the base differences between the two strains being 64 out of 1027 nucleotides in the m gene and 52 out of 740 in the ns1 gene. based on the assumptions that thes ... | 1984 | 6495656 |
| hemagglutinin of swine influenza virus: a single amino acid change pleiotropically affects viral antigenicity and replication. | the complete nucleotide sequence has been obtained of the h1 hemagglutinin (ha) gene of a high-yielding (h) mutant of the a/nj/11/76(h1n1) strain of swine influenza virus in studies of a viral reassortant (x-53a) bearing this gene. this determination has permitted comparison with human influenza h1n1 prototype viruses a/wsn/33 and a/pr/8/34, with which 80% and 94% amino acid homology was found between ha1 and ha2, respectively. partial sequences have been determined for other viral reassortants ... | 1983 | 6580621 |
| [experimental swine influenza. comparison of the pathogenicity of swine-type wild influenza viruses and strains of human type h3 n2 whose reservoir is swine]. | intra-nasal inoculation of 10-day-old piglets, free of specific pathogenic flora, with swine influenza virus a/h1 n1 and a/h3 n2 produces lesions of viral pneumonia without detectable clinical signs. following indirect contamination all the strains studied were able to multiply in the respiratory tract; in those cases where no macroscopic lesion was seen, microscopic examination revealed variable modification of the pulmonary tissue depending on the virus causing infection. influenza virus type ... | 1983 | 6614787 |
| the ecology of influenza viruses: a who memorandum. | influenza a viruses continue to be isolated from man, pigs, horses, and a wide range of avian species, especially ducks. the recent isolation of an influenza a virus from seals has added an additional mammal to the list of natural hosts for these viruses. in contrast, influenza b viruses have been isolated only from man.the haemagglutinin of a virus isolated from gulls in the united states of america could not be identified with reference antisera and may constitute a new haemagglutinin subtype. ... | 1981 | 6978194 |
| genomic analysis of matrix gene and antigenic studies of its gene product (m1) of a swine influenza virus (h1n1) causing chronic respiratory disease in pigs. | the nucleotide sequence of gene coding for the matrix protein (m1 and m2) of swine influenza (h1n1) virus, a/sw/quebec/5393/91 (swqc91), associated with chronic respiratory disease in pigs, was determined. the deduced amino acid (aa) sequence was compared with the other north american swine strains including the a/sw/quebec/192/81 (swqc81) strain associated with the chronic and acute respiratory disease in pigs. separate analysis of the m1 and m2 gene products showed different evolutions. m1 had ... | 2000 | 11129631 |
| pathogenic and antigenic properties of phylogenetically distinct reassortant h3n2 swine influenza viruses cocirculating in the united states. | swine influenza is an acute respiratory disease caused by type a influenza viruses. before 1998, swine influenza virus isolates in the united states were mainly of the classical h1n1 lineage. since then, phylogenetically distinct reassortant h3n2 viruses have been identified as respiratory pathogens in pigs on u.s. farms. the h3n2 viruses presently circulating in the u.s. swine population are triple reassortants containing avian-like (pa and pb2), swine-like (m, np, and ns), and human-like (ha, ... | 2003 | 12843064 |
| investigations of the efficacy of european h1n1- and h3n2-based swine influenza vaccines against the novel h1n2 subtype. | the efficacy of a commercial swine influenza vaccine based on a/new jersey/8/76 (h1n1) and a/port chalmers/1/73 (h3n2) strains was tested against challenge with an h1n2 swine influenza virus. influenza virus-seronegative pigs were vaccinated twice with the vaccine when they were four and eight weeks old, or with the same vaccine supplemented with an h1n2 component. control pigs were left unvaccinated. three weeks after the second vaccination, all the pigs were challenged intratracheally with the ... | 2003 | 12877210 |
| exogenous porcine viruses. | porcine organs, cells and tissues provide a viable source of transplants in humans, though there is some concern of public health risk from adaptation of swine infectious agents in humans. limited information is available on the public health risk of many exogenous swine viruses, and reliable and rapid diagnostic tests are available for only a few of these. the ability of several porcine viruses to cause transplacental fetal infection (parvoviruses, circoviruses, and arteriviruses), emergence or ... | 2003 | 12934944 |
| [reactions with kaolin, swine influenza virus and albumen inhibitor of virus hemagglutination]. | | 1952 | 13012848 |
| a comparison of diagnostic assays for the detection of type a swine influenza virus from nasal swabs and lungs. | nasal swabs and lung samples from pigs experimentally infected with h1n1 swine influenza virus (siv) were examined for the presence of siv by the indirect fluorescent antibody assay, immunohistochemistry, cell culture virus isolation, egg inoculation, and 2 human enzyme immunoassays (membrane enzyme immunoassay, microwell enzyme immunoassay). egg inoculation was considered to be the gold standard for assay evaluation. the 2 human enzyme immunoassays (eia) and egg inoculation agreed 100% for the ... | 2001 | 11243361 |
| effect of dietary intake of fat-soluble vitamins on intensity of experimental swine influenza virus infection in mice. | | 1956 | 13325406 |