| antibody-mediated growth of infectious salmon anaemia virus in macrophage-like fish cell lines. | infectious salmon anaemia virus (isav), a pathogen in marine aquaculture, belongs to the genus isavirus, family orthomyxoviridae. there is limited information on how isav interacts with host defences. to study isav-antibody interactions, virus neutralization (vn) assays were performed in the cell lines chse-214, shk-1 and to using three strains of isav and rabbit or fish anti-isav sera. homologous vn titres of >1 : 1280 in chse-214 cells corresponded to titres of only 1 : 80 in the macrophage-li ... | 2003 | 12810863 |
| infectious salmon anemia virus: causative agent, pathogenesis and immunity. | infectious salmon anemia (isa) virus (isav), an economically important new pathogen in marine aquaculture, is classified in the family orthomyxoviridae, genus isavirus. the main structural properties of this genus include enveloped virions 90-140 nm in diameter with surface projections of a combined receptor-binding hemagglutinin and receptor-destroying enzyme activity demonstrated to be an esterase, hence recently designated he, and a genome composed of eight segments of linear, single-stranded ... | 2004 | 15460541 |
| infectious salmon anemia virus (isav) genomic segment 3 encodes the viral nucleoprotein (np), an rna-binding protein with two monopartite nuclear localization signals (nls). | infectious salmon anemia virus (isav) is the type species of the genus isavirus belonging to the orthomyxoviridae, and causes serious disease in atlantic salmon (salmo salar). this study presents the expression and functional analysis of the isav genome segment 3, and provides further evidence that it encodes the viral nucleoprotein (np). the encoded protein was expressed in a baculovirus system, and western blot analysis showed that it corresponds to the 66-71 kda structural protein previously ... | 2004 | 15522447 |
| lack of evidence of infectious salmon anemia virus in pollock pollachius virens cohabitating with infected farmed atlantic salmon salmo salar. | the infectious salmon anemia (isa) virus causes lethargy, anemia, hemorrhage of the internal organs, and death in farmed atlantic salmon salmo salar. it has been a cause of disease in norwegian farmed atlantic salmon since 1984 and has since been identified in canada, scotland, the united states, and the faroe islands. wild fish have been proposed as a viral reservoir because they are capable of close contact with farmed salmon. laboratory studies have shown that brown trout and sea trout salmo ... | 2004 | 15584421 |
| estimation of specificity and sensitivity of three diagnostic tests for infectious salmon anaemia virus in the absence of a gold standard. | reverse transcriptase-polymerase chain reaction (rt-pcr), virus isolation (vi) and indirect fluorescent antibody test (ifat) are three tests currently used by the salmon industry to identify fish infected with the infectious salmon anaemia virus (isav). however, very limited information is available on the sensitivity and specificity of these methods. in order to evaluate these tests in fish representing a range of farmed atlantic salmon populations, five laboratories participated in a blind stu ... | 2005 | 15705154 |
| estimation of the repeatability and reproducibility of three diagnostic tests for infectious salmon anaemia virus. | reverse transcriptase polymerase chain reaction (rt-pcr), virus isolation (vi) and indirect fluorescent antibody tests (ifat) are three assays currently used by the salmon industry to identify fish infected with infectious salmon anaemia virus (isav). however, no data are available on the repeatability (within-laboratory consistency) and reproducibility (between-laboratory consistency) of these assays and very limited information is available on the effect of freezing samples on test results. in ... | 2005 | 15705155 |
| application of surveillance data in evaluation of diagnostic tests for infectious salmon anemia. | infectious salmon anemia (isa) is a viral disease in farmed atlantic salmon salmo salar, characterized by lethargy, anorexia, anemia and death. test methods used for regulatory decisions to remove infected cages include the indirect fluorescent antibody test (ifat), the reverse transcription-polymerase chain reaction test (rt-pcr), and virus isolation (vi). however, no thorough evaluation of these diagnostic tests has been carried out on field samples. the objective of this study was to evaluate ... | 2005 | 15819427 |
| expression, antigenicity and studies on cell receptor binding of the hemagglutinin of infectious salmon anemia virus. | infectious salmon anemia (isa) virus belongs to the proposed genus isavirus of orthomyxoviridae and is an emerging pathogen in atlantic salmon (salmo salar) farming. the hemagglutinin-esterase (he) of isa virus share several characteristics with the influenza virus hemagglutinin. this study reports recombinant expression of different isa virus he mutants in fish cell lines. some introduced mutations, representing minimal differences in single amino acid residues, resulted in remarkable effects o ... | 2005 | 15824888 |
| combined use of the ask and shk-1 cell lines to enhance the detection of infectious salmon anemia virus. | infectious salmon anemia (isa) is a severe disease primarily affecting commercially farmed atlantic salmon (salmo salar) in seawater. the disease has been reported in portions of canada, the united kingdom, the faroe islands, and the united states. infectious salmon anemia virus (isav), the causative agent of isa, has also been isolated from several asymptomatic marine and salmonid fish species. diagnostic assays for the detection of isav include virus isolation in cell culture, a reverse transc ... | 2005 | 15825496 |
| correlation of virus replication in tissues with histologic lesions in atlantic salmon experimentally infected with infectious salmon anemia virus. | we have studied the replication of virus in tissues and development of lesions associated with infectious salmon anemia virus (isav) infection in atlantic salmon using in situ hybridization (ish) with a riboprobe targeting isav rna segment 7 messenger rna. fish were infected with three isav isolates (u5575-1, rpc-01-0593-1, norway 810/9/99) and then euthanatized sequentially at 3, 6, 10, and 13 days postinoculation (dpi) and thereafter once a week for 8 weeks. severe histopathologic lesions were ... | 2005 | 15872380 |
| using expert opinion to identify risk factors important to infectious salmon-anemia (isa) outbreaks on salmon farms in maine, usa and new brunswick, canada. | thirty industry or regulatory professionals, with extensive experience in the local infectious salmon-anemia (isa) epidemic, were queried on their opinions regarding the spread and impact of isa in maine, usa and new brunswick, canada. subjective probability-estimation techniques were used to elicit likelihood ratios (lr) for risk factors of potential relevance to the epidemic. experts were asked to answer questions based on their direct and local experience with isa, rather than through knowled ... | 2005 | 15967239 |
| characterization of the infectious salmon anemia virus fusion protein. | infectious salmon anemia virus (isav) is an orthomyxovirus causing serious disease in atlantic salmon (salmo salar l.). this study presents the characterization of the isav 50-kda glycoprotein encoded by segment 5, here termed the viral membrane fusion protein (f). this is the first description of a separate orthomyxovirus f protein, and to our knowledge, the first ph-dependent separate viral f protein described. the isav f protein is synthesized as a precursor protein, f0, that is proteolytical ... | 2005 | 16160182 |
| risk factors for outbreaks of infectious salmon anemia in farmed atlantic salmon, salmo salar. | infectious salmon anemia (isa) is a viral disease occurring in farmed atlantic salmon (salmo salar) that is characterized by lethargy, anorexia, anemia and death. to control the disease in new brunswick, canada, 7.5 million fish from outbreak cages have been destroyed since 1997. despite changes made by farmers, 2002 was the worst year ever for isa losses in the region. we evaluated the associations between potential risk factors and isa outbreaks in the atlantic-salmon sites in new brunswick. t ... | 2005 | 16188335 |
| viremia during infectious salmon anemia virus infection of atlantic salmon is associated with replicating virus in leucocytes. | in situ hybridization (ish) was used to investigate the presence of viral mrna in different fractions of blood cells of atlantic salmon between 6 and 12 d following experimental infection with infectious salmon anemia virus (isav). using a riboprobe targeting isav segment 7 mrna, hybridization signals were observed only in leucocytes in buffy coat smears from samples collected from 8 to 12 d post-infection (dpi). none of the red blood cell smears from any sample showed ish signal. these observat ... | 2005 | 16231641 |
| mortality patterns in infectious salmon anaemia virus outbreaks in new brunswick, canada. | mortality levels attributed to infectious salmon anaemia viral (isav) infections were examined at the net pen and site level in the 1996 smolt year class in three areas of new brunswick, canada. the year class in this region was the first known to have potential exposure to isav beginning at the time of seawater transfer. there was considerable variability in mortality patterns among net pen groups of fish. net pen outbreak definitions were based on at least seven high mortality days in which th ... | 2005 | 16303026 |
| risk factors associated with mortalities attributed to infectious salmon anaemia virus in new brunswick, canada. | outbreaks of unexplained mortalities attributed to infectious salmon anaemia (isa) were examined in the 1996 year class of atlantic salmon in three regions of new brunswick, canada. a total of 218 net pens at 14 sites deemed to have been exposed to isa virus (isav) were surveyed for mortality records and management, environmental and host characteristics. based on definitions of mortality patterns, clinical isa disease outbreaks occurred in 106 net pens. there were eight sites in which >50% of n ... | 2005 | 16303027 |
| characterization of chinook head salmon embryo phenotypes of infectious salmon anemia virus by real-time rt-pcr. | we have previously described the development of a onetube sybr green real-time rt-pcr assay for the detection and quantitation of infectious salmon anemia virus (isav) in various biological samples. the twofold aim of the present study was to verify that the optimized sybr green real-time rt-pcr conditions could detect isav isolates of different geographic origins, and to analyze the growth patterns of the selected isav isolates in the chinook head salmon embryo (chse) -214 cells by this assay t ... | 2006 | 16645343 |
| validation of reference genes for real-time polymerase chain reaction studies in atlantic salmon. | optimization of reference genes for real-time polymerase chain reaction (pcr) studies in fish is strongly needed. we systematically tested beta-actin (actb), 18s rrna (18s), beta(2)-microglobulin (b2m), elongation factor 1-alpha (ef1a), rna polymerase i and ii (rpl1/2), and glycerol 6-phosphate dehydrogenase (g6pdh) for stability in salmon immune relevant tissues and kidney cells (ask) infected with infectious salmon anemia virus (isav), plus in tissues from fish fed thia fatty acids. transcript ... | 2006 | 16676145 |
| rapid development of polyclonal antisera against infectious salmon anaemia virus and its optimization and application as a diagnostic tool. | infectious salmon anaemia is an important disease of atlantic salmon. one of the current methods of diagnosis is the indirect fluorescent antibody test (ifat), using a monoclonal antibody specific to the haemagglutinin of the virus. the conformationally dependent nature of this antibody could be a drawback in its usefulness in other tests. this study describes the development and optimization of a polyclonal antiserum against infectious salmon anaemia virus, including a method of separating viru ... | 2006 | 16677319 |
| sequence analysis of the fusion protein gene from infectious salmon anemia virus isolates: evidence of recombination and reassortment. | studies of infectious salmon anemia virus (isav; genus isavirus, family orthomyxoviridae) haemagglutinin-esterase (he) gene sequences have shown that this gene provides a tool for genotyping and, hence, a tool to follow the dissemination of isav. the problem with using only the he gene is that isav has a segmented genome and one segment may not tell the whole story about the origin and history of isav from outbreaks. to achieve a better genotyping system, the present study has focused on segment ... | 2006 | 16760406 |
| expression of mhc class i pathway genes in response to infectious salmon anaemia virus in atlantic salmon (salmo salar l.) cells. | infectious salmon anaemia virus (isav) is the causative agent of an important viral disease threatening atlantic salmon aquaculture. although its structure and pathogenesis is well described little is known about its immunomodulatory effects on the host. cellular immunity is critical in the host control of virus infections, an event attributable to antigen presentation through the mhc class i pathway, whose genes are transcriptionally activated by interferons (ifn) and other cytokines. in this s ... | 2006 | 16772112 |
| in vivo correlates of infectious salmon anemia virus pathogenesis in fish. | the phenotypic correlates of pathogenicity for infectious salmon anemia virus (isav) in salmonid fishes have not been thoroughly studied to date. in this study, a comparison was made of 13 different strains of isav, isolated from different geographical regions between 1997 and 2004, for their infectivity in three fish species [atlantic salmon (salmo salar), coho salmon (oncorhynchus kisutch) and rainbow trout (oncorhynchus mykiss)]. when the different virus isolates were used at an approximate i ... | 2006 | 16894204 |
| development, application and validation of a taqman real-time rt-pcr assay for the detection of infectious salmon anaemia virus (isav) in atlantic salmon (salmo salar). | infectious salmon anaemia (isa) is a disease of cultured atlantic salmon (salmo salar) which was successfully eradicated from scotland following its emergence in 1998. the rapid deployment of sensitive diagnostic methods for the detection of isa virus (isav) was fundamental to the swift eradication of isa disease in scotland and continues to be of crucial importance to surveillance of the aquaculture industry. this study reports the development, validation, application and interpretation of two ... | 2006 | 17058489 |
| hydrographics and the timing of infectious salmon anemia outbreaks among atlantic salmon (salmo salar l.) farms in the quoddy region of maine, usa and new brunswick, canada. | infectious salmon anemia (isa) has caused severe morbidity and mortality in farmed atlantic salmon in north america, norway, scotland and the faroe islands. the quoddy region of maine, united states of america (usa), and new brunswick (nb), canada is characterized by extensive tidal mixing and close proximity between farms. this region is also prone to recurrent appearances of isa, though control measures limit disease spread and severity on infected farms. we conducted a retrospective longitudi ... | 2007 | 17097172 |
| detection of infectious salmon anaemia virus by real-time nucleic acid sequence based amplification. | we have developed a real-time nucleic acid sequence based amplification (nasba) procedure for detection of infectious salmon anaemia virus (isav). primers were designed to target a 124 nucleotide region of isav genome segment 8. amplification products were detected in real-time with a molecular beacon (carboxyfluorescin [fam]-labelled and methyl-red quenched) that recognised an internal region of the target amplicon. amplification and detection were performed at 41 degrees c for 90 min in a corb ... | 2006 | 17140133 |
| cloning and expression analysis of an atlantic salmon (salmo salar l.) tapasin gene. | loading of the major histocompatibility complex (mhc) class i molecule with peptide is mediated by the multimeric peptide-loading complex in the er where the glycoprotein tapasin (tapbp) is required for stabilization of the complex and for control of peptide loading onto mhc class i. to expand our knowledge on antigen presentation genes in atlantic salmon, we isolated a full-length salmon tapasin cdna sequence (sasa-tapbp). it encoded a 443 bp amino acid sequence with two n-glycosylation sites, ... | 2007 | 17157378 |
| demonstration of infectious salmon anaemia virus (isav) endocytosis in erythrocytes of atlantic salmon. | infectious salmon anaemia (isa) virus (isav) is a fish orthomyxovirus that has recently been assigned to the new genus isavirus within the family orthomyxoviridae. it possesses the major functional characteristics of the virus family including haemagglutinating, receptor destroying enzyme (rde), and fusion activities associated with the virion surface proteins. it is generally accepted that isav agglutinates erythrocytes of several fish species and that the isav rde activity dissolves this haema ... | 2007 | 17254352 |
| spatial and non-spatial risk factors associated with cage-level distribution of infectious salmon anaemia at three atlantic salmon, salmo salar l., farms in maine, usa. | the distribution of infectious salmon anaemia (isa) was examined among 80 cages from three atlantic salmon grow-out farms in maine, usa that were stocked with smolts from a single hatchery. cage-level disease was broadly defined as one or more moribund fish testing positive for infectious salmon anaemia virus (isav) by rt-pcr and a second confirmatory test (ifat, culture or genotype sequence). spatio-temporal and cage-level risks were explored using logistic regression and survival analysis. non ... | 2007 | 17298565 |
| fate of infectious salmon anaemia virus (isav) in experimentally challenged blue mussels mytilus edulis. | in order to investigate the potential role of blue mussels mytilus edulis as a vector of the fish pathogenic infectious salmon anaemia virus (isav), we developed an experimental bioaccumulation system in which mussels can accumulate virus during normal filtration. detection of virus in mussels was performed by means of real-time rt-pcr. isav-rna was detected in the mussels until 72 h post-challenge. hepatopancreas homogenate from experimentally challenged mussels was injected into salmon. all th ... | 2007 | 17425257 |
| effect of early infectious salmon anaemia virus (isav) infection on expression of mhc pathway genes and type i and ii interferon in atlantic salmon (salmo salar l.) tissues. | a number of viral diseases affecting teleost fish are characterized but few studies have addressed the effects of viral infection on gene expression in vivo. in this study, we investigated the effect of the early stages of infectious salmon anaemia virus (isav) infection on important components of the innate and adaptive immune response by monitoring expression of five genes in the mhc class i pathway, mhc class iibeta, type i ifn-alpha, mx, and type ii ifn-gamma from cohabitant-infected atlanti ... | 2007 | 17478098 |
| infectious salmon anaemia virus (isav) in experimentally challenged atlantic cod (gadus morhua). | juvenile atlantic cod, gadus morhua, (6 g) were challenged with infectious salmon anaemia virus (isav) either by intraperitoneal (i.p.) injection or by cohabitation with isa-diseased atlantic salmon (salmo salar). samplings of cod were performed over a period of 45 days and various tissue samples were collected. the presence of isav rna (segment 8) in samples was assessed by both conventional rt-pcr and a competitive quantitative real-time rt-pcr. in the i.p.-challenged group, isav rna was detec ... | 2007 | 17610125 |
| fish genotype significantly influences susceptibility of juvenile rainbow trout, oncorhynchus mykiss (walbaum), to waterborne infection with infectious salmon anaemia virus. | | 2007 | 17850579 |
| mapping of putative virulence motifs on infectious salmon anemia virus surface glycoprotein genes. | infectious salmon anemia virus (isav) is classified in the genus isavirus of the family orthomyxoviridae. although virulence variation of isav can be demonstrated experimentally in fish, virus strain identification is ambiguous because the correlates of pathogenicity and/or antigenicity of isav are not well defined. thirteen isav isolates characterized for their ability to kill fish were used to search for markers of virulence on the virus surface glycoprotein genes; haemagglutinin-esterase (he) ... | 2007 | 17947536 |
| morphologic description of infectious salmon anaemia virus (isav)-induced lesions in rainbow trout oncorhynchus mykiss compared to atlantic salmon salmo salar. | in the present study the pathogenesis of experimental infectious salmon anaemia virus (isav) infection in rainbow trout oncorhynchus mykiss (walbaum, 1972) and atlantic salmon salmo salar was compared. the virus infection in the 2 species demonstrated different mortality patterns and pathology characteristics. atlantic salmon showed a typical acute mortality pattern peaking at 8 to 16 d post-infection (dpi) depending on virus dose, whereas in rainbow trout, only the highest virus dose (10(7.13-7 ... | 2007 | 18159667 |
| peptide-binding motif prediction by using phage display library for sasauba*0301, a resistance haplotype of mhc class i molecule from atlantic salmon (salmo salar). | the structure of the peptide-binding specificity of major histocompatibility complex (mhc) class i has been analyzed extensively in human and mouse. for fish, there are no crystallographic models of mhc molecules, neither are there data on the peptide-binding specificity. in this study, we describe for the first time the identification of a fish class i peptide-mhc ligand binding motif. phage display technology using both 7 mer and 12 mer libraries enabled us to identify peptide ligands with uni ... | 2008 | 18206244 |
| epidemiological investigation of infectious salmon anaemia (isa) outbreaks in norway 2003-2005. | epidemiological information was summarized from 32 outbreaks of infectious salmon anaemia (isa) on salmon farming sites in norway in 2003-2005. virus isolates from the outbreak sites were genotyped, and the genotyping was used to assess possible associations between outbreak sites due to adjacent location, sharing fish farming authorisation, sharing smolt suppliers or sharing broodfish origin of the fish. the isa outbreaks were distributed along most of the norwegian coast and showed a variable ... | 2008 | 18243376 |
| molecular and functional characterization of two infectious salmon anaemia virus (isav) proteins with type i interferon antagonizing activity. | in this study we characterize two proteins encoded by the two smallest genomic segments of the piscine orthomyxovirus infectious salmon anaemia virus (isav). both proteins, encoded by the un-spliced orf from genomic segment 7 (s7orf1) and the larger orf from segment 8 (s8orf2), are involved in modulation of the type i interferon (ifn) response. the data suggests that the s7orf1 protein is collinearly encoded, non-structural, contains no nuclear localisation signals, localises mainly to the cytop ... | 2008 | 18304672 |
| infectious salmon anaemia virus replication and induction of alpha interferon in atlantic salmon erythrocytes. | infectious salmon anaemia (isa) virus (isav), which causes isa in marine-farmed atlantic salmon, is an orthomyxovirus belonging to the genus isavirus, family orthomyxoviridae. isav agglutinates erythrocytes of several fish species and it is generally accepted that the isav receptor destroying enzyme dissolves this haemagglutination except for atlantic salmon erythrocytes. recent work indicates that isav isolates that are able to elute from atlantic salmon erythrocytes cause low mortality in chal ... | 2008 | 18307775 |
| using pseudogold standards and latent-class analysis in combination to evaluate the accuracy of three diagnostic tests. | we previously reported our use of latent-class models to estimate the sensitivity (se) and specificity (sp) for each of three tests used to monitor farmed salmon for infectious salmon anaemia virus (isav). those tests were reverse-transcriptase polymerase chain reaction (rt-pcr), virus isolation (vi), and an indirect immunofluorescent-antibody test (ifat). we used tissues from 403 salmon from four populations presumed to have different prevalence of isav. however, no formal evaluation of the ass ... | 2008 | 18355935 |
| the nucleoprotein and the viral rna of infectious salmon anemia virus (isav) are localized in the nucleolus of infected cells. | the infectious salmon anemia virus (isav), which belongs to the new genus isavirus of the orthomyxoviridae family, is an important pathogen of the salmon farming industry. indirect immunofluorescence assays carried out with monoclonal antibodies specific for the nucleoprotein (np) reveal differential staining of sub-cellular compartments in infected cells. particularly interesting was the staining of the nucleolus, which showed co-localization with nucleolin in chse-214, epc and shk-1 cells infe ... | 2008 | 18632128 |
| structural and functional studies of an irf-7-like gene from atlantic salmon. | interferon regulatory factor 7 (irf-7) plays a crucial role in virus-induced activation of interferon-alpha/beta transcription in mammals. this work describes a structural and functional homologue of mammalian irf-7 from atlantic salmon. the cloned gene encodes a putative protein of 415 amino acids (aa), which groups with mammalian irf-7 and other fish irf-7-like proteins in a phylogenetic analysis of vertebrate irfs. using an ifn promoter-luciferase assay we showed that salmon irf-7 gave increa ... | 2009 | 18778729 |
| infectious salmon anemia virus is a powerful inducer of key genes of the type i interferon system of atlantic salmon, but is not inhibited by interferon. | infectious salmon anemia virus (isav) is an aquatic orthomyxovirus causing disease and high mortality in farmed atlantic salmon (salmo salar). the virus is thus apparently able to initiate replication without being hampered by the host's immune system. in this work we have studied the role of the type i interferon (ifn) system of atlantic salmon in protection against isav. real-time rt-pcr was used to study the expression of type i ifn and the ifn stimulated genes mx and isg15 in to cells and li ... | 2007 | 17257858 |
| isolation and expression profile of a gene encoding for the signal transducer and activator of transcription stat2 in atlantic salmon (salmo salar). | signal transducer and activator of transcription (stat)-2 is a molecule involved in the type i interferon (ifn) signalling pathway. the full length cdna sequence of atlantic salmon (salmo salar) ssstat2 was determined and phylogenetic analysis of the amino acid sequence grouped this novel salmon gene to the stat2 clade. this represents the first fish stat2 report. the gene encodes for a 802 aa polypeptide that has 38% identity to the human or murine stat2. the expression was monitored by qpcr in ... | 2009 | 19428483 |
| detection and identification of ihn and isa viruses by isothermal dna amplification in microcapillary tubes. | unique base sequences derived from rna of both infectious hematopoietic necrosis virus (ihnv) and infectious salmon anemia virus (isav) were detected and identified using a combination of surface-associated molecular padlock dna probes (mpps) and rolling circle amplification (rca) in microcapillary tubes. dna oligonucleotides with base sequences identical to rna obtained from ihnv or isav were recognized by mpps. circularized mpps were then captured on the inner surfaces of glass microcapillary ... | 2006 | 17072595 |
| transmission of infectious salmon anaemia virus (isav) in farmed populations of atlantic salmon (salmo salar). | in the present study, 24 smolt production sites were screened for the presence of infectious salmon anaemia virus (isav) with the help of a specific real-time rt pcr assay, and 22 of these sites had smolts that were positive. if these smolt production sites are representative for the prevalence of isav in norwegian smolts, then most marine production sites must be considered to be positive for isav. in addition, 92 european isav isolates have been genotyped based on the hemagglutinin-esterase ge ... | 2007 | 16941061 |
| infectious salmon anaemia virus (isav) isolated from the isa disease outbreaks in chile diverged from isav isolates from norway around 1996 and was disseminated around 2005, based on surface glycoprotein gene sequences. | infectious salmon anaemia (isa) virus (isav) is a pathogen of marine-farmed atlantic salmon (salmo salar); a disease first diagnosed in norway in 1984. for over 25 years isav has caused major disease outbreaks in the northern hemisphere, and remains an emerging fish pathogen because of the asymptomatic infections in marine wild fish and the potential for emergence of new epidemic strains. isav belongs to the family orthomyxoviridae, together with influenza viruses but is sufficiently different t ... | 2009 | 19558648 |
| expression kinetics of interferon and interferon-induced genes in atlantic salmon (salmo salar) following infection with infectious pancreatic necrosis virus and infectious salmon anaemia virus. | infectious pancreatic necrosis virus (ipnv) and infectious salmon anaemia virus (isav) are economically important pathogens of the salmonid aquaculture industry. atlantic salmon were challenged by intraperitoneal injection (i.p.) with either virus followed by time-course sampling. cohabiting fish in the ipnv challenge were also sampled. kidney tissue was analysed using a taqman real-time pcr assay to measure the expression of a range of host immune genes in relation to the endogenous control, el ... | 2007 | 16806972 |
| nucleic acid sensing by regenerable surface-associated isothermal rolling circle amplification. | a novel method for regenerating biosensors has been developed in which the highly specific detection of nucleic acid sequences is carried out using molecular padlock probe (mpp) technology and surface-associated rolling circle amplification (rca). this technique has a low occurrence of false positive results when compared to polymerase chain reaction, and is an isothermal reaction, which is advantageous in systems requiring low power consumption such as remote field sensing applications. gold-sp ... | 2007 | 16797962 |
| detection of infectious haematopoietic necrosis virus and infectious salmon anaemia virus by molecular padlock amplification. | a new method for the molecular detection of the fish pathogens, infectious haematopoietic necrosis virus (ihnv) and infectious salmon anaemia virus (isav), is described. by employing molecular padlock probe (mpp) technology combined with rolling circle amplification (rca) and hyperbranching (hbr), it is possible to detect rna target sequence from these viruses at levels comparable with those detected by the polymerase chain reaction (pcr), but without prior reverse transcription. the use of mpp ... | 2006 | 16635060 |
| how specific mhc class i and class ii combinations affect disease resistance against infectious salmon anaemia in atlantic salmon (salmo salar). | the aim was to evaluate the performance of selected individual mhc class i and class ii alpha (a) alleles, and combinations of these on disease resistance against infectious salmon anaemia (isa). the material consisting of 1966 fish from seven families, contained five mhc class i alleles and four mhc class ii a alleles. which representing given class ii a and class ii beta (b) haplotypes, totalling 19 mhc class i and class ii a genotypes. the fish were challenged with infectious salmon anaemia v ... | 2006 | 16616518 |
| comparison of lethal versus non-lethal sample sources for the detection of infectious salmon anemia virus (isav). | the emergence of infectious salmon anemia virus (isav) in canada and the usa has led to the establishment of isav surveillance programs for cultured atlantic salmon (salmo salar l.) and wild fish species, including atlantic salmon. current testing procedures for isav consist of viral culture, reverse-transcription polymerase chain reaction (rt-pcr) and indirect fluorescent antibody testing (ifat), and require lethal sampling. as the focus of this study, blood was evaluated as a possible non-leth ... | 2005 | 16261932 |
| a stochastic model for the assessment of the transmission pathways of heart and skeleton muscle inflammation, pancreas disease and infectious salmon anaemia in marine fish farms in norway. | salmon farming is threatened, economically and ecologically, by infectious diseases. to reduce the risk of epidemics, authorities have developed regulations. these are based on quantitative understanding of pathways of infection, representing disease specific risks. a stochastic model was fitted to historical data, to estimate risk factors associated with competing spread mechanisms. three infectious diseases were compared, heart and skeletal muscle inflammation (hsmi), pancreas disease (pd) and ... | 2010 | 19811843 |
| identification of an interferon antagonist protein encoded by segment 7 of infectious salmon anaemia virus. | infectious salmon anaemia virus (isav) is an orthomyxovirus and member of the genus isavirus, which contains eight genomic segments coding for ten viral proteins. this study focussed on identifying the function of the largest protein encoded by isav genomic segment 7 (7i), which like influenza a segment 7 encodes two proteins, one of which is based on removal of an intron from the primary transcript. using two independent methods, an mx1 promoter-driven reporter system and real-time pcr of facs- ... | 2006 | 16202469 |
| evaluation of histopathology, real-time pcr and virus isolation for diagnosis of infectious salmon anaemia in norwegian salmon using latent class analysis. | | 2010 | 20298446 |
| prevalence of infectious salmon anaemia virus (isav) in wild salmonids in western norway. | studies of infectious salmon anaemia virus (isav), an important pathogen of farmed salmon in norway, scotland, the faeroe islands, ireland, canada, the usa and chile, suggest that natural reservoirs for this virus can be found on both sides of the north atlantic. based on existing information about isav it is believed to be maintained in wild populations of trout and salmon in europe. it has further been suggested that isav is transmitted between wild hosts, mainly during their freshwater spawni ... | 2005 | 16175969 |
| genetic markers of the immune response of atlantic salmon (salmo salar) to infectious salmon anemia virus (isav). | infectious diseases among fish present an important economic burden for the aquaculture and fisheries industries around the world. for example, the infectious salmon anemia virus (isav) infects farmed atlantic salmon (salmo salar), and results in millions of dollars of lost revenue to salmon farmers. although improved management and husbandry practices over the last few years have minimized the losses and the number of outbreaks, the risk of new virulent strains emerging is a looming threat to t ... | 2010 | 20371292 |
| comparative genomics identifies candidate genes for infectious salmon anemia (isa) resistance in atlantic salmon (salmo salar). | infectious salmon anemia (isa) has been described as the hoof and mouth disease of salmon farming. isa is caused by a lethal and highly communicable virus, which can have a major impact on salmon aquaculture, as demonstrated by an outbreak in chile in 2007. a quantitative trait locus (qtl) for isa resistance has been mapped to three microsatellite markers on linkage group (lg) 8 (chr 15) on the atlantic salmon genetic map. we identified bacterial artificial chromosome (bac) clones and three fing ... | 2011 | 20396924 |
| constitutive expression of atlantic salmon mx1 protein in chse-214 cells confers resistance to infectious salmon anaemia virus. | infectious salmon anaemia (isa) is a highly fatal viral disease affecting marine-farmed atlantic salmon which is caused by isa virus (isav), a fish orthomyxovirus that has recently been assigned to the new genus isavirus within the family orthomyxoviridae. mx proteins are among the interferon (ifn)-induced proteins responsible for the development of an antiviral state in vertebrate cells. we used real-time reverse transcription-polymerase chain reaction (rt-pcr) and chinook salmon embryo (chse-2 ... | 2005 | 16124877 |
| interspecies and intraspecies transmission of influenza a viruses: viral, host and environmental factors. | influenza a viruses are enveloped viruses belonging to the family orthomyxoviridae that encompasses four more genera: influenza b, influenza c, isavirus and thogotovirus. type a viruses belong to the only genus that is highly infectious to a variety of mammalian and avian species. they are divided into subtypes based on two surface glycoproteins, the hemagglutinin (ha) and neuraminidase (na). so far, 16 ha and 9 na subtypes have been identified worldwide, making a possible combination of 144 sub ... | 2010 | 20591213 |
| protective effects of a dna vaccine expressing the infectious salmon anemia virus hemagglutinin-esterase in atlantic salmon. | infectious salmon anemia (isa) is a disease, caused by an orthomyxovirus, which has considerable economic impact on farming of atlantic salmon. here we describe the results of immunization against isa using plasmids expressing the isa virus hemagglutinin-esterase (he). immunized atlantic salmon demonstrated moderate protection after challenge with isa virus, with relative percent survival of 39.5 and 60.5 in two parallel groups. no protection was seen after immunization using a plasmid expressin ... | 2005 | 16005119 |
| bioinformatic analysis of the genome of infectious salmon anemia virus associated with outbreaks with high mortality in chile. | the infectious salmon anemia virus (isav), an orthomyxovirus, is the major cause of outbreaks of high mortality rates in salmon in chile. it has been proposed that the virulence of isav isolates lies mainly in hemagglutinin-esterase and fusion glycoproteins. however, based on current information, the contribution of other viral genes cannot be ruled out. to study this, we isolated and determined the complete coding sequence of two high-prevalence chilean isolates associated with outbreaks of hig ... | 2010 | 20810724 |
| comparative virulence of infectious salmon anaemia virus isolates in atlantic salmon, salmo salar l. | infectious salmon anaemia virus (isav) surveillance in the bay of fundy has identified the existence of a large number of genetically distinct isav isolates which appear to be of variable virulence. genetically distinct isolates are currently being designated based on sequencing of the hyper polymorphic region (hpr) of genomic segment 6, which encodes the haemagglutinin-esterase protein, but it has been difficult to elucidate a clear association between these molecular variations and variations ... | 2009 | 19261043 |
| identification of the 3' and 5' terminal sequences of the 8 rna genome segments of european and north american genotypes of infectious salmon anemia virus (an orthomyxovirus) and evidence for quasispecies based on the non-coding sequences of transcripts. | infectious salmon anemia (isa) virus (isav) is a pathogen of marine-farmed atlantic salmon (salmo salar); a disease first diagnosed in norway in 1984. this virus, which was first characterized following its isolation in cell culture in 1995, belongs to the family orthomyxoviridae, genus, isavirus. the isavirus genome consists of eight single-stranded rna segments of negative sense, each with one to three open reading frames flanked by 3' and 5' non-coding regions (ncrs). although the terminal se ... | 2010 | 21092282 |
| completion of the full-length genome sequence of the infectious salmon anemia virus, an aquatic orthomyxovirus-like, and characterization of mabs. | we report here the first full-length sequence of the eight ssrna genome segments of the infectious salmon anemia virus (isav, glesvaer/2/90 isolate), a salmonid orthomyxovirus-like. comparison of isav genome sequence with those of others orthomyxovirus reveals low identity values, and a remarkable feature is the extremely long 5' end utr of isav segments, which all contain an additional conserved motif of unknown function. in addition to the genome nucleotide sequence determination, specific mab ... | 2010 | 21123552 |
| epidemiological investigation into the re-emergence and control of an outbreak of infectious salmon anaemia in the shetland islands, scotland. | infectious salmon anaemia (isa) is an orthomyxoviral disease, primarily affecting marine-phase farmed atlantic salmon, which can result in high levels of mortality. isa first emerged in norway in the 1980s and subsequently has occurred in canada, the usa, the faeroe islands and chile. an outbreak occurred in scotland in 1998-1999, but was eradicated at a cost of over pounds sterling 20m. the epidemiology of a new outbreak of isa in the scottish shetland islands during 2008-2009 is described. six ... | 2010 | 21133319 |
| a low-pathogenic variant of infectious salmon anemia virus (isav-hpr0) is highly prevalent and causes a non-clinical transient infection in farmed atlantic salmon (salmo salar l.) in the faroe islands. | infectious salmon anemia virus (isav) is an orthomyxovirus responsible for a significant disease of farmed atlantic salmon. fallowing and re-establishment of the atlantic salmon farming industry in the faroes following a recent devastating infectious salmon anaemia (isa) disease epidemic provided a unique opportunity to study the risk of re-emergence of disease. over 53 months, 2787 of 34 573 (8.1%) apparently healthy atlantic salmon analysed tested positive for isav by rt-pcr. sequence analysis ... | 2010 | 21148272 |
| inflammation and innate immune response against viral infections in marine fish. | viral infections in fish are common in both natural and cultured fish populations and the spread of infectious disease is a serious threat to both natural ecosystems and commercial exploitations. a significant body of studies have addressed the host response to viral infection including the efficacy of dna vaccines however we still have a fragmented vision of both pathologies associated with viral infection and the immune response to those across fish species. many studies have concentrated upon ... | 2010 | 21184664 |
| development of a widely applicable positive control strategy to support detection of infectious salmon anaemia virus (isav) using taqman real-time pcr. | real-time pcr assays are being increasingly applied to the detection of fish pathogens due to their sensitivity, specificity and potential for high throughput sample processing. such assays allow for the ready and efficient inclusion of appropriate quality controls which are fundamental to scientific integrity and to satisfying the demands of diagnostic test accreditation. in this article, we report development of a universal positive control strategy for real-time pcr assays, which has been use ... | 2009 | 19261042 |
| isa virus in chile: evidence of vertical transmission. | infectious salmon anaemia virus (isav), genus isavirus (family orthomyxoviridae), is present in all large salmon (salmo salar)-producing countries around the north atlantic. the target species for this virus are members of the genus salmo, but the virus may also replicate in other salmonids introduced to the north atlantic (oncorhychus spp.). existing isa virus isolates can be divided into two major genotypes, a north american (na) and a european (eu) genotype, based on phylogenetic analysis of ... | 2009 | 19034606 |
| heterologous expression and purification of the infectious salmon anemia virus hemagglutinin esterase. | this study presents the heterologous production and purification of a soluble and functional form of the hemagglutinin esterase (he) of the infectious salmon anemia virus (isav) isolate 4 (glesvaer/2/90). the he possesses receptor binding and receptor destroying enzyme (rde) activity and is probably involved in the infection process. the recombinant he protein (reche 4) was expressed in insect cells (sf9) using the baculovirus expression vector system. both the transmembrane region and the cytop ... | 2008 | 18799134 |
| use of molecular epidemiology to trace transmission pathways for infectious salmon anaemia virus (isav) in norwegian salmon farming. | infectious salmon anaemia (isa) is a disease affecting farmed atlantic salmon, and most salmon producing countries have experienced isa outbreaks. the aim of the present study was to use epidemiological and viral sequence information to trace transmission pathways for isa virus (isav) in norwegian salmon farming. | 2011 | 21420655 |
| characterization and comparison of the full 3' and 5' untranslated genomic regions of diverse isolates of infectious salmon anaemia virus by using a rapid and universal method. | the 3' and 5' untranslated regions (utrs) of the gene segments of orthomyxoviruses interact closely with the polymerase complex and are important for viral replication and transcription regulation. despite this, the 3' and 5' rna utrs of the infectious salmon anaemia virus (isav) genome have only been partially characterized and little is known about the level of conservation between different virus subtypes. this report details for the first time, the adaptation of a rapid method for the simult ... | 2011 | 21458495 |
| host range, host specificity and hypothesized host shift events among viruses of lower vertebrates. | abstract: the successful replication of a viral agent in a host is a complex process that often leads to a species specificity of the virus and can make interspecies transmission difficult. despite this difficulty, natural host switch seems to have been frequent among viruses of lower vertebrates, especially fish viruses, since there are several viruses known to be able to infect a wide range of species. in the present review we will focus on well documented reports of broad host range, variatio ... | 2011 | 21592358 |
| inhibitory effect of a nucleotide analog on infectious salmon anemia virus infection. | the infectious salmon anemia virus (isav), which belongs to the orthomyxoviridae family, has been responsible for major losses in the salmon industry, with mortalities close to 100% in areas where atlantic salmon (salmo salar) is grown. this work studied the effect of ribavirin (1-β-d-ribofuranosyl-1,2,3-triazole-3-carbaxaide), a broad-spectrum antiviral compound with proven ability to inhibit the replicative cycle of the dna and rna viruses. the results show that ribavirin was able to inhibit t ... | 2011 | 21653663 |
| [taxonomic structure of orthomyxoviridae: current views and immediate prospects]. | analysis of taxonomic structure of orthomyxoviridae was undertaken in view of its anticipated evolution. four concepts of circulation of influenza a viruses in the biosphere are discussed, viz. anthrponose, zooanthroponose, metastrongilose, and protozoan. all of them may be considered in the framework of the general zooantroponose concept. influenza b and c viruses can not be regarded as strictly anthroponose. comparative molecular-genetic analysis of the genus thogotovirus provides a basis for ... | 2011 | 21786592 |
| absolute quantitation of infectious salmon anaemia virus using different real-time reverse transcription pcr chemistries. | routine laboratory diagnosis of infectious salmon anaemia virus (isav) infection is primarily by reverse transcription polymerase chain reaction (rt-pcr) because of the high sensitivity and rapid turnaround time of the test. this paper describes methods for highly reproducible absolute viral load measurements using external standard curves generated with either isav recombinant plasmid dna (pdna) standards or transcribed rna standards prepared by in vitro transcription with t7 rna polymerase, an ... | 2008 | 18789975 |
| first detection, isolation and molecular characterization of infectious salmon anaemia virus associated with clinical disease in farmed atlantic salmon (salmo salar) in chile. | infectious salmon anaemia (isa) is a viral disease of marine-farmed atlantic salmon (salmo salar) caused by isa virus (isav), which belongs to the genus isavirus, family orthomyxoviridae. the virus is considered to be carried by marine wild fish and for over 25 years has caused major disease outbreaks in marine-farmed atlantic salmon in the northern hemisphere. in the southern hemisphere, isav was first detected in chile in 1999 in marine-farmed coho salmon (oncorhynchus kisutch). in contrast to ... | 2008 | 18680586 |
| transcriptomic analysis of responses to infectious salmon anemia virus infection in macrophage-like cells. | the aquatic orthomyxovirus infectious salmon anemia virus (isav) is an important pathogen for salmonid aquaculture, however little is known about protective and pathological host responses to infection. we have investigated intracellular responses during cytopathic isav infection in the macrophage-like atlantic salmon kidney (ask) cell line by microarray analysis (1.8k sfa2.0 immunochip) and a functional assay for glutathione. gene transcription changed rapidly and consistently with time and wit ... | 2008 | 18534703 |
| gene expression analyses in atlantic salmon challenged with infectious salmon anemia virus reveal differences between individuals with early, intermediate and late mortality. | infectious salmon anemia virus (isav) causes a multisystemic disease responsible for severe losses in salmon aquaculture. better understanding of factors that explain variations in resistance between individuals and families is essential for development of strategies for disease control. to approach this, we compared global gene expression using microarrays in fish dying early and late in the time course following infection from a highly pathogenic isav. | 2008 | 18423000 |
| evolutionary mechanisms involved in the virulence of infectious salmon anaemia virus (isav), a piscine orthomyxovirus. | infectious salmon anaemia virus (isav) is an orthomyxovirus causing a multisystemic, emerging disease in atlantic salmon. here we present, for the first time, detailed sequence analyses of the full-genome sequence of a presumed avirulent isolate displaying a full-length hemagglutinin-esterase (he) gene (hpr0), and compare this with full-genome sequences of 11 norwegian isav isolates from clinically diseased fish. these analyses revealed the presence of a virulence marker right upstream of the pu ... | 2008 | 18280528 |
| estimating diagnostic test accuracy for infectious salmon anaemia virus in maine, usa. | infectious salmon anaemia virus (isav) is a pathogen of consequence to farmed atlantic salmon, salmo salar l. isa control centres on active surveillance for early detection by reverse transcription polymerase chain reaction (rt-pcr), indirect fluorescent antibody assay (ifat) and virus isolation. because diagnostic test performance varies among populations and laboratories, the office international des epizooties (oie) recommends an evaluation of test accuracy in each region of use. this is comp ... | 2008 | 18234019 |
| characterization of gene expression on genomic segment 7 of infectious salmon anaemia virus. | infectious salmon anaemia (isa) virus (isav), an important pathogen of fish that causes disease accompanied by high mortality in marine-farmed atlantic salmon, is the only species in the genus isavirus, one of the five genera of the orthomyxoviridae family. the isavirus genome consists of eight single-stranded rna species, and the virions have two surface glycoproteins; haemagglutinin-esterase (he) protein encoded on segment 6 and fusion (f) protein encoded on segment 5. based on the initial dem ... | 2007 | 17394643 |
| an economic evaluation of the control of three notifiable fish diseases in the united kingdom. | we summarised the challenges faced in an ex ante cost-benefit appraisal of united kingdom government spending on disease surveillance for three notifiable fish diseases: infectious salmon anaemia (isa), viral haemorrhagic septicaemia (vhs) and infectious haemorrhagic necrosis (ihn). we used a social cost-benefit analysis and adopted a national perspective. we compared costs of current public and private surveillance effort with the benefits stated in terms of the avoided private and social costs ... | 2007 | 17391788 |
| a stochastic model for infectious salmon anemia (isa) in atlantic salmon farming. | infectious salmon anemia (isa) is one of the main infectious diseases in atlantic salmon farming with major economical implications. despite the strong regulatory interventions, the isa epidemic is not under control, worldwide. we study the data covering salmon farming in norway from 2002 to 2005 and propose a stochastic space-time model for the transmission of the virus. we model seaway transmission between farm sites, transmission through shared management and infrastructure, biomass effects a ... | 2007 | 17301014 |
| epidemiologic investigation of the re-emergence of infectious salmon anemia virus in chile. | reports from surveillance activities were analyzed to determine the epidemiology of the re-emergence of infectious salmon anemia virus (isav) in atlantic salmon farms in chile. the epidemic and spatial and spatiotemporal patterns were described, taking into account commercial compartmentalization of the farms. during the 64 wk study period, 76 isav-infected salmon farms, representing 17 companies, were reported in 65% of the management geographic zones of the 10th region in southern chile. appro ... | 2009 | 19476280 |
| an experimental investigation on aspects of infectious salmon anaemia virus (isav) infection dynamics in seawater atlantic salmon, salmo salar l. | this study investigated infection dynamics of infectious salmon anaemia virus (isav) by conducting two experiments to examine minimum infective dose and viral shedding of isav. in terms of minimum infective dose, the high variability between replicate tanks and the relatively slow spread of infection through the population at 1 x 10(1) tcid(50) ml(-1) indicated this dose is approaching the minimum infective dose for isav in seawater salmon populations. a novel qpcr assay incorporating an influen ... | 2009 | 19538641 |
| analysis of host- and strain-dependent cell death responses during infectious salmon anemia virus infection in vitro. | infectious salmon anemia virus (isav) is an aquatic orthomyxovirus and the causative agent of infectious salmon anemia (isa), a disease of great importance in the atlantic salmon farming industry. in vitro, isav infection causes cytophatic effect (cpe) in cell lines from atlantic salmon, leading to rounding and finally detachment of the cells from the substratum. in this study, we investigated the mode of cell death during in vitro isav infection in different atlantic salmon cell lines, using fo ... | 2009 | 19566966 |
| selection of a cutoff value for real-time polymerase chain reaction results to fit a diagnostic purpose: analytical and epidemiologic approaches. | diagnostic laboratories frequently select a subjective cutoff value for real-time amplification assays, above which a threshold cycle (ct) value is deemed false. commonly, higher ct values are interpreted as amplification or fluorescence artifacts, or cross contaminations. although the implementation of ct cutoff might be reasonable, its justification and selection should be based on evidence. the current article reviewed evidence-based strategies to select ct cutoffs grouped in analytical and e ... | 2011 | 21217022 |
| depletion of cd8 alpha cells from tissues of atlantic salmon during the early stages of infection with high or low virulent strains of infectious salmon anaemia virus (isav). | the virulence of an infectious salmon anaemia virus (isav) isolate is influenced by the response of the host's immune system to virus infection. here we report the fate of immune responsive cells in head kidney, spleen and gills of atlantic salmon during infection with high and low virulent strains of isav. a comparison of real-time pcr detection of virus and immunohistochemical detection of immune responsive cells revealed that peak viral load was coincident with both an elevated presence of mh ... | 2011 | 21316389 |
| modelling the spread of infectious salmon anaemia among salmon farms based on seaway distances between farms and genetic relationships between infectious salmon anaemia virus isolates. | infectious salmon anaemia (isa) is an important infectious disease in atlantic salmon farming causing recurrent epidemic outbreaks worldwide. the focus of this paper is on tracing the spread of isa among norwegian salmon farms. to trace transmission pathways for the isa virus (isav), we use phylogenetic relationships between virus isolates in combination with space-time data on disease occurrences. the rate of isa infection of salmon farms is modelled stochastically, where seaway distances betwe ... | 2011 | 21325314 |
| the effect of sub-culturing on the basal level of type i interferon (ifn) gene expression in the salmon head kidney (shk-1) cell line. | over sub-culturing a cell line generates a selective pressure which can result in key cellular functions being altered such as gene and protein expression. the present study set out to determine whether serial sub-culturing affects the antiviral state of the salmon head kidney (shk-1) cell line. cells were cultured under constant conditions and real-time pcr was performed to measure the level of interferon (ifn) and mx gene expression over different passage numbers. a significant increase in the ... | 2009 | 19573606 |
| infectious salmon anaemia virus (isav) isolates induce distinct gene expression responses in the atlantic salmon (salmo salar) macrophage/dendritic-like cell line to, assessed using genomic techniques. | infectious salmon anaemia virus (isav) is a marine orthomyxovirus of significant interest not only as a cause of a fatal disease of farmed atlantic salmon resulting in severe economic losses to the aquaculture industry, but also as the only poikilothermic orthomyxovirus. isav targets vascular endothelial cells and macrophages, and is known to influence the expression of both innate and adaptive immune response relevant genes. isav isolates from different geographic regions have been shown to var ... | 2009 | 19616850 |
| traditional descriptive analysis and novel visual representation of diagnostic repeatability and reproducibility: application to an infectious salmon anaemia virus rt-pcr assay. | as a component of diagnostic test evaluation, the estimation of repeatability and reproducibility of an assay is necessary to assess the robustness and the transferability of the method among laboratories. respectively defined as the agreement within and between laboratories, repeatability and reproducibility of a qualitative diagnostic test are traditionally reported using observed proportion of agreement or kappa values. applied to a recently designed rt-pcr assay for the detection of infectio ... | 2009 | 19748139 |
| in situ localisation of major histocompatibility complex class i and class ii and cd8 positive cells in infectious salmon anaemia virus (isav)-infected atlantic salmon. | it is assumed that the mobilisation of a strong cellular immune response is important for the survival of atlantic salmon infected with infectious salmon anaemia virus (isav). in this study, the characterisation of immune cell populations in tissues of non-isav infected atlantic salmon and during the early viraemia of isav was undertaken. immunohistochemical investigations of spleen, head kidney and gills using monoclonal antibodies against recombinant proteins from mhc i, ii and cd8 were perfor ... | 2010 | 19766193 |
| surveillance for infectious salmon anaemia virus hpr0 in marine atlantic salmon farms across scotland. | infectious salmon anaemia virus (isav) is a serious and commercially important pathogen of atlantic salmon. multiple viruses have been defined based on a highly polymorphic region (hpr) of the haemagglutinin-esterase (he) protein encoded by genomic segment 6. the viruses causing disease outbreaks in farms to date all have deletions in this region with respect to a putative ancestral variant with a longer hpr (hpr0). the presence of hpr0 nucleic acid has been detected in many countries including ... | 2009 | 20099410 |
| formation of autophagosomes and redistribution of lc3 upon in vitro infection with infectious salmon anemia virus. | autophagy plays an important role in both cellular homeostasis and cellular stress responses, and is also implicated in viral immunity. here we show that infectious salmon anemia virus (isav) induce autophagy (double membrane autophagosomes observed by em), in cells from atlantic salmon. in addition, cells transfected with the standard autophagy marker, microtubule-associated protein light chain kinase 3 (lc3) fused to green fluorescent protein (lc3-gfp), displayed the redistribution of fluoresc ... | 2010 | 20350574 |
| structural and functional analysis of the hemagglutinin-esterase of infectious salmon anaemia virus. | infectious salmon anaemia virus (isav) is a piscine orthomyxovirus causing a serious disease in farmed atlantic salmon (salmo salar l.). the virus surface glycoprotein hemagglutinin-esterase (he) is responsible for both viral attachment and release. similarity to bovine and porcine torovirus hemagglutinin-esterase (btov he, ptov he), bovine coronavirus he (bcov he) and influenza c hemagglutinin-esterase-fusion (infc hef) proteins were exploited in a computational homology-based structure analysi ... | 2010 | 20398710 |
| taqman real-time rt-pcr detection of infectious salmon anaemia virus (isav) from formalin-fixed paraffin-embedded atlantic salmon salmo salar tissues. | the objective of this study was to evaluate the application of a taqman real-time reverse transcriptase pcr (rt-pcr) assay for the detection of infectious salmon anaemia virus (isav) in formalin-fixed paraffin-embedded (ffpe) fish tissues from atlantic salmon salmo salar with and without clinical signs of infection, and to compare it with histological and immunohistochemical (ihc) techniques. sixteen fish samples obtained in 2007 and 2008 from 4 different farms in chile were examined. the real-t ... | 2010 | 20597427 |
| infectious salmon anemia virus--genetics and pathogenesis. | the infectious salmon anemia virus (isav) is the causative agent of the isa syndrome that affects mainly atlantic salmon (salmo salar) and has caused high mortality epidemics in norway, scotland, canada, the united states and chile. it is classified as an orthomyxoviridae, its genome is composed of 8 single-strand rna segments with negative polarity that code for 11 polypeptides. through functional studies of the coded proteins it has been established that rna segments 5 and 6 code for a fusion ... | 2010 | 20979983 |
| structural characterization of the viral and crna panhandle motifs from the infectious salmon anemia virus. | infectious salmon anemia virus (isav) has emerged as a virus of great concern to the aquaculture industry since it can lead to highly contagious and lethal infections in farm-raised salmon populations. while little is known about the transcription/replication cycle of isav, initial evidence suggests that it follows molecular mechanisms similar to those found in other orthomyxoviruses, which include the highly pathogenic influenza a (inf a) virus. during the life cycle of orthomyxoviruses, a panh ... | 2011 | 21994446 |