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Sample records for septicaemia virus vhsv

  1. Virulence of viral haemorrhagic septicaemia virus (VHSV) genotype III in rainbow trout.

    PubMed

    Ito, Takafumi; Kurita, Jun; Mori, Koh-ichiro; Olesen, Niels J

    2016-01-08

    In general, viral haemorrhagic septicaemia virus (VHSV) isolates from marine fish species in European waters (genotypes GIb, GII and GIII) are non- to low virulent in rainbow trout. However, a VHSV isolation was made in 2007 from a disease outbreak in sea farmed rainbow trout in Norway. The isolate, named NO-2007-50-385, was demonstrated to belong to GIII. This isolate has attracted attention to assess which of the viral genome/proteins might be associated with the virulence in rainbow trout. In this study, we describe the difference of virulence in rainbow trout between the NO-2007-50-385 and 4p168 isolates as representatives of virulent and non-virulent GIII isolates, respectively. Rainbow trout were bath challenged with VHSV NO-2007-50-385 for 1 and 6 h, resulting in cumulative mortalities of 5 and 35%, respectively. No mortality was observed in the rainbow trout groups immersed with the genotype III VHSV isolate 4p168 for 1 and 6 h. The viral titre in organs from fish challenged with NO-2007-50-385 for 6 h increased more rapidly than those exposed for 1 h. By in vitro studies it was demonstrated that the final titres of VHSV DK-3592B (GI), NO-2007-50-385 and 4p168 inoculated on EPC cells were very similar, whereas when inoculated on the rainbow trout cell line RTG-2 the titre of the non-virulent 4p168 isolate was 3-4 logs below the two other VHSV isolates. Based on a comparative analysis of the entire genome of the genotype III isolates, we suggest that substitutions of amino acids in positions 118-123 of the nucleo-protein are candidates for being related to virulence of VHSV GIII in rainbow trout.

  2. Risks associated with commodity trade: transmission of viral haemorrhagic septicaemia virus (VHSV) to rainbow trout fry from VHSV-carrying tissue-homogenates.

    PubMed

    Oidtmann, B; Joiner, C; Reese, R A; Stone, D; Dodge, M; Dixon, P

    2011-06-01

    Movements of commodity fish present a potential risk of transferring pathogens. Within a study to estimate the risk from imported rainbow trout Oncorhynchus mykiss carcases, fry were exposed to tissue homogenates from market size rainbow trout infected experimentally with viral haemorrhagic septicaemia (VHS) by waterborne exposure to VHS virus (VHSV, isolate of genotype Ia). Tissues were collected from fish that showed clinical signs and from recent mortalities. Homogenates of (i) internal organs, (ii) brain/gills and (iii) muscle tissue were prepared and added to tanks holding the fry. Virus transmission occurred from all tissues tested, causing high mortality of the fry. The results underline the potential risk of introduction of VHSV through the trade of fish products.

  3. Molecular epidemiology of viral haemorrhagic septicaemia virus (VHSV) in British Columbia, Canada, reveals transmission from wild to farmed fish.

    PubMed

    Garver, Kyle A; Traxler, Garth S; Hawley, Laura M; Richard, Jon; Ross, Jay P; Lovy, Jan

    2013-05-27

    Viral haemorrhagic septicaemia virus (VHSV) is a fish pathogen found throughout the Northern Hemisphere and is capable of infecting and causing mortality in numerous marine and freshwater hosts. In the coastal waters of British Columbia, Canada, the virus has been detected for 20 yr with many occurrences of mass mortalities among populations of Pacific herring Clupea pallasii (Valenciennes) and sardine Sardinops sagax as well as detections among cultured Atlantic Salmo salar and Chinook Oncorhynchus tshawytscha salmon. We compared nucleotide sequence of the full glycoprotein (G) gene coding region (1524 nt) of 63 VHSV isolates sampled during its recorded presence from 1993 to 2011 from 6 species and a total of 29 sites. Phylogenetic analysis showed that all isolates fell into sub-lineage IVa within the major VHSV genetic group IV. Of the 63 virus isolates, there were 42 unique sequences, each of which was ephemeral, being repeatedly detected at most only 1 yr after its initial detection. Multiple sequence types were revealed during single viral outbreak events, and genetic heterogeneity was observed within isolates from individual fish. Moreover, phylogenetic analysis revealed a close genetic linkage between VHSV isolates obtained from pelagic finfish species and farmed salmonids, providing evidence for virus transmission from wild to farmed fish.

  4. Interferon response following infection with genetically similar isolates of viral haemorrhagic septicaemia virus (VHSV) exhibiting contrasting virulence in rainbow trout.

    PubMed

    Campbell, S; McBeath, A; Secombes, C; Snow, M; Collet, B

    2011-01-01

    Isolates of viral haemorrhagic septicaemia virus (VHSV) were identified which are genetically similar yet, based on their isolation history were considered likely to differ in virulence in juvenile rainbow trout. An experimental infection study was performed in order to verify this hypothesis and provide an experimental infectivity model with which to investigate the basis for susceptibility of rainbow trout to this commercially important virus. Significant differences in mortality were obtained following both intraperitoneal (IP) injection and immersion challenges with an early marine (DK-M.Rhabdo) and early rainbow trout VHSV isolate (DK-F1) respectively. Expression of Type I IFN, Mx1 (an IFN-inducible protein), and viral genes (encoding nucleo-, phospho-, matrix, glyco- and non-viron proteins) was studied in sequential tissue samples using real-time quantitative PCR (QPCR). Resulting data revealed a significant increase in IFN and Mx1 expression detected in fish challenged by IP injection with both isolates. Expression levels of these genes were directly related to the degree of viral replication as measured by the expression of VHSV RNAs. In immersion-challenged fish a significant increase in Mx1 was observed only when using the virulent isolate DK-F1; however no elevated host response was detectable in fish challenged with the marine isolate DK-M.Rhabdo. Quintessentially the inability to detect any virus in trout challenged with the marine isolate via immersion suggests the virus was incapable of establishing infection. The mechanisms for this appear to be more related to initial cellular entry and replication rather than due to the overcoming of initial infection via an elevated host innate immune response. PMID:21056106

  5. Viral replication in excised fin tissues (VREFT) corresponds with prior exposure of Pacific herring, Clupea pallasii (Valenciennes), to viral haemorrhagic septicaemia virus (VHSV)

    USGS Publications Warehouse

    Grady, C.A.; Gregg, J.L.; Wade, R.M.; Winton, J.R.; Hershberger, P.K.

    2011-01-01

    Procedures for a viral replication in excised fin tissue (VREFT) assay were adapted to Pacific herring, Clupea pallasii, and optimized both to reduce processing time and to provide the greatest resolution between na??ve herring and those previously exposed to viral haemorrhagic septicaemia virus (VHSV), Genogroup IVa. The optimized procedures included removal of the left pectoral fin from a euthanized fish, inoculation of the fin with >105 plaque-forming units (PFU) mL-1 VHSV for 1 h, rinsing the fin in fresh medium six times to remove unadsorbed virions, incubation of the fin in fresh medium for 4 days and enumeration of the viral titre in a sample of the incubation medium by plaque assay. The optimized VREFT assay was effective at identifying the prior exposure history of laboratory-reared Pacific herring to VHSV. The geometric mean VREFT value was significantly greater (P < 0.01) among na??ve herring (1.2 ?? 103 PFU mL-1) than among groups that survived exposure to VHSV (1.0-2.9 ?? 102 PFU mL-1); additionally, the proportion of cultures with no detectable virus was significantly greater (P = 0.0002) among fish that survived exposure to VHSV (39-47%) than among na??ve fish (3.3%). The optimized VREFT assay demonstrates promise for identifying VHSV exposure history and forecasting disease potential in populations of wild Pacific herring. ?? 2010 Blackwell Publishing Ltd.

  6. In vivo virulence of viral haemorrhagic septicaemia virus (VHSV) in rainbow trout Oncorhynchus mykiss correlates inversely with in vitro Mx gene expression.

    PubMed

    Cano, Irene; Collet, Bertrand; Pereira, Clarissa; Paley, Richard; van Aerle, Ronny; Stone, David; Taylor, Nick G H

    2016-05-01

    The in vitro replication of viral haemorrhagic septicaemia virus (VHSV) isolates from each VHSV genotype and the associated cellular host Mx gene expression were analysed. All the isolates were able to infect RTG-2 cells and induce increased Mx gene expression (generic assay detecting isoforms 1 and 3 [Mx1/3]). A trout pathogenic, genotype Ia isolate (J167), showing high replication in RTG-2 cells (by infective titre and N gene expression) induced lower Mx1/3 gene expression than observed in VHSV isolates known to be non-pathogenic to rainbow trout: 96-43/8, 96-43/10 (Ib); 1p49, 1p53 (II); and MI03 (IVb). Paired co-inoculation assays were analysed using equal number of plaque forming units per ml (PFU) of J167 (Ia genotype) with other less pathogenic VHSV genotypes. In these co-inoculations, the Mx1/3 gene expression was significantly lower than for the non-pathogenic isolate alone. Of the three rainbow trout Mx isoforms, J167 did not induce Mx1 up-regulation in RTG-2 or RTgill-W1 cells. Co-inoculating isolates resulted in greater inhibition of Mx in both rainbow trout cell lines studied. Up-regulation of sea bream Mx in SAF-1 cells induced by 96-43/8 was also lower in co-inoculation assays with J167. The RTG-P1 cell line, expressing luciferase under the control of the interferon-induced Mx rainbow trout gene promoter, showed low luciferase activity when inoculated with pathogenic strains: J167, DK-5131 (Ic), NO-A-163/68 (Id), TR-206239-1, TR-22207111 (Ie), 99-292 (IVa), and CA-NB00-01 (IVc). Co-inoculation assays showed a J167-dose dependent inhibition of the luciferase activity. The data suggest that virulent VHSV isolates may interfere in the interferon pathways, potentially determining higher pathogenicity.

  7. In vivo virulence of viral haemorrhagic septicaemia virus (VHSV) in rainbow trout Oncorhynchus mykiss correlates inversely with in vitro Mx gene expression.

    PubMed

    Cano, Irene; Collet, Bertrand; Pereira, Clarissa; Paley, Richard; van Aerle, Ronny; Stone, David; Taylor, Nick G H

    2016-05-01

    The in vitro replication of viral haemorrhagic septicaemia virus (VHSV) isolates from each VHSV genotype and the associated cellular host Mx gene expression were analysed. All the isolates were able to infect RTG-2 cells and induce increased Mx gene expression (generic assay detecting isoforms 1 and 3 [Mx1/3]). A trout pathogenic, genotype Ia isolate (J167), showing high replication in RTG-2 cells (by infective titre and N gene expression) induced lower Mx1/3 gene expression than observed in VHSV isolates known to be non-pathogenic to rainbow trout: 96-43/8, 96-43/10 (Ib); 1p49, 1p53 (II); and MI03 (IVb). Paired co-inoculation assays were analysed using equal number of plaque forming units per ml (PFU) of J167 (Ia genotype) with other less pathogenic VHSV genotypes. In these co-inoculations, the Mx1/3 gene expression was significantly lower than for the non-pathogenic isolate alone. Of the three rainbow trout Mx isoforms, J167 did not induce Mx1 up-regulation in RTG-2 or RTgill-W1 cells. Co-inoculating isolates resulted in greater inhibition of Mx in both rainbow trout cell lines studied. Up-regulation of sea bream Mx in SAF-1 cells induced by 96-43/8 was also lower in co-inoculation assays with J167. The RTG-P1 cell line, expressing luciferase under the control of the interferon-induced Mx rainbow trout gene promoter, showed low luciferase activity when inoculated with pathogenic strains: J167, DK-5131 (Ic), NO-A-163/68 (Id), TR-206239-1, TR-22207111 (Ie), 99-292 (IVa), and CA-NB00-01 (IVc). Co-inoculation assays showed a J167-dose dependent inhibition of the luciferase activity. The data suggest that virulent VHSV isolates may interfere in the interferon pathways, potentially determining higher pathogenicity. PMID:27066706

  8. Application of a sensitive, specific and controlled real-time PCR assay to surveillance indicates a low prevalence of viral haemorrhagic septicaemia virus (VHSV) in wild herring, Clupea harengus L., in Scottish waters.

    PubMed

    Matejusova, I; McKay, P; Bland, F; Snow, M

    2010-10-01

    Surveillance data on the distribution of viral haemorrhagic septicaemia virus (VHSV) in the North Sea (UK), targeting Atlantic herring in areas with previous virus detection, were obtained from research cruises conducted during 2005. The sensitive molecular approach of real-time RT-PCR (qRT-PCR) was applied alongside a newly developed endogenous positive control assay specific for herring (elongation factor 1α) to ensure integrity of template. Three hundred and five pools from 1937 individual herring were tested, and no evidence of VHSV in association with wild Atlantic herring was detected. Samples were obtained from Scottish waters where marine aquaculture is conducted. The results confirm that previous tissue culture studies have most likely not significantly underestimated the prevalence of carrier herring in this area. The significance of migratory species such as herring as a reservoir species for VHSV, with the potential to translocate virus genotypes between geographical areas, is discussed. PMID:20735797

  9. Application of a sensitive, specific and controlled real-time PCR assay to surveillance indicates a low prevalence of viral haemorrhagic septicaemia virus (VHSV) in wild herring, Clupea harengus L., in Scottish waters.

    PubMed

    Matejusova, I; McKay, P; Bland, F; Snow, M

    2010-10-01

    Surveillance data on the distribution of viral haemorrhagic septicaemia virus (VHSV) in the North Sea (UK), targeting Atlantic herring in areas with previous virus detection, were obtained from research cruises conducted during 2005. The sensitive molecular approach of real-time RT-PCR (qRT-PCR) was applied alongside a newly developed endogenous positive control assay specific for herring (elongation factor 1α) to ensure integrity of template. Three hundred and five pools from 1937 individual herring were tested, and no evidence of VHSV in association with wild Atlantic herring was detected. Samples were obtained from Scottish waters where marine aquaculture is conducted. The results confirm that previous tissue culture studies have most likely not significantly underestimated the prevalence of carrier herring in this area. The significance of migratory species such as herring as a reservoir species for VHSV, with the potential to translocate virus genotypes between geographical areas, is discussed.

  10. Differential effects of viral hemorrhagic septicaemia virus (VHSV) genotypes IVa and IVb on gill epithelial and spleen macrophage cell lines from rainbow trout (Oncorhynchus mykiss).

    PubMed

    Pham, P H; Lumsden, J S; Tafalla, C; Dixon, B; Bols, N C

    2013-02-01

    The two most prominent genotypes of viral hemorrhagic septicemia virus (VHSV) are -I in the Northeastern Atlantic region and -IV in North America, but much more is known about the cellular pathogenesis of genotype -I than -IV. VHSV genotype -IV is divided into -IVa from the Northeast Pacific Ocean and -IVb from the Great Lakes and both of which are less virulent to rainbow trout than genotype -I. In this work, infections of VHSV-IVa and -IVb have been studied in two rainbow trout cell lines, RTgill-W1 from the gill epithelium, and RTS11 from spleen macrophages. RTgill-W1 produced infectious progeny of both VHSV-IVa and -IVb. However, VHSV-IVa was more infectious than -IVb toward RTgill-W1: -IVa caused cytopathic effect (CPE) at a lower viral titre, elicited CPE earlier, and yielded higher titres. By contrast, no CPE and no increase in viral titre were observed in RTS11 cultures infected with either genotype. Yet in RTS11 all six VHSV genes were expressed and antiviral genes, Mx2 and Mx3, were up regulated by VHSV-IVb and -IVa. However, replication appeared to terminate at the translational stage as viral N protein, presumably the most abundant of the VSHV proteins, was not detected in either infected RTS11 cultures. In RTgill-W1, Mx2 and Mx3 were up regulated to similar levels by both viral genotypes, while VHSV-IVa induced higher levels of IFN1, IFN2 and LGP2A than VHSV-IVb.

  11. Analysis of the nucleoprotein gene identifies three distinct lineages of viral haemorrhagic septicemia virus (VHSV) within the European marine environment

    USGS Publications Warehouse

    Snow, M.; Cunningham, C.O.; Melvin, W.T.; Kurath, G.

    1999-01-01

    A ribonuclease (RNase) protection assay (RPA) has been used to detect nucleotide sequence variation within the nucleoprotein gene of 39 viral haemorrhagic septicaemia virus (VHSV) isolates of European marine origin. The classification of VHSV isolates based on RPA cleavage patterns permitted the identification of ten distinct groups of viruses based on differences at the molecular level. The nucleotide sequence of representatives of each of these groupings was determined and subjected to phylogenetic analysis. This revealed grouping of the European marine isolates of VHSV into three genotypes circulating within distinct geographic areas. A fourth genotype was identified comprising isolates originating from North America. Phylogenetic analyses indicated that VHSV isolates recovered from wild caught fish around the British Isles were genetically related to isolates responsible for losses in farmed turbot. Furthermore, a relationship between naturally occurring marine isolates and VHSV isolates causing mortality among rainbow trout in continental Europe was demonstrated. Analysis of the nucleoprotein gene identifies distinct lineages of viral haemorrhagic septicaemia virus within the European marine environment. Virus Res. 63, 35-44. Available from: 

  12. Differentially expressed genes after viral haemorrhagic septicaemia virus infection in olive flounder (Paralichthys olivaceus).

    PubMed

    Hwang, Jee Youn; Kwon, Mun-Gyeong; Seo, Jung Soo; Do, Jung Wan; Park, Myoung-Ae; Jung, Sung-Hee; Ahn, Sang Jung

    2016-09-25

    A strain of viral haemorrhagic septicaemia virus (VHSV) was isolated from cultured olive flounder (Paralichthys olivaceus) during epizootics in South Korean. This strain showed high mortality to olive flounder in in vivo challenge experiment. The complete genomic RNA sequences were determined and phylogenetic analysis of the amino acid sequences of glycoprotein revealed that this isolate was grouped into genotype IVa of genus Novirhabdovirus. Expression profile of genes in olive flounder was analyzed at day 1 and day3 after infection with this VHSV isolate by using cDNA microarray containing olive flounder 13K cDNA clones. Microarray analysis revealed 785 up-regulated genes and 641 down-regulated genes by at least two-fold in virus-infected fish compared to healthy control groups. Among 785 up-regulated genes, we identified seven immune response-associated genes, including the interferon (IFN)-induced 56-kDa protein (IFI56), suppressor of cytokine signaling 1 (SOCS1), interleukin 8 (IL-8), cluster of differentiation 83 (CD83), α-globin (HBA), VHSV-induced protein-6 (VHSV6), and cluster of differentiation antigen 9 (CD9). Our results confirm previous reports that even virulent strain of VHSV induces expression of genes involved in protective immunity against VHSV. PMID:27599933

  13. Survey of viral haemorrhagic septicaemia virus in wild fishes in the southeastern Black Sea.

    PubMed

    Ogut, H; Altuntas, C

    2014-05-13

    Species diversity in the Black Sea ecosystem has been declining rapidly over the last 2 decades. To assess the occurrence and distribution of viral haemorrhagic septicaemia virus (VHSV) in various wild fish species, a wild marine fish survey was carried out in 2009, 2010, and 2011. The pooled or individual samples of kidney, liver, and spleen of 5025 specimens, belonging to 17 fish species, were examined virologically using cell culture. The cells showing cytopathic effects (CPE) were subjected to ELISA and multiplex reverse transcriptase polymerase chain reaction (RT-mPCR), for VHSV and infectious pancreatic necrosis virus (IPNV), after blind passaging to determine the virus species causing CPE. The virus species and possibility of co-infection with IPNV were verified by the RT-mPCR developed in this study. Twelve species of fish (pontic shad Alosa immaculata, red mullet Mullus barbatus, three-bearded rockling Gaidropsarus vulgaris, black scorpionfish Scorpaena porcus, Mediterranean horse mackerel Trachurus mediterraneus, whiting Merlangius merlangus euxinus, stargazer Uranoscopus scaber, pilchard Sardina pilchardus, garfish Belone belone, round goby Neogobius melanostomus, thornback ray Raja clavata, and anchovy Engraulis encrasicolus) tested positive for VHSV Genotype Ie (VHSV-Ie). Except whiting, pilchard, and round goby, the rest are new host records for VHSV. The extent and spread of VHSV-Ie was significantly higher among bottom fish than among pelagic fish. Sensitivity and specificity of the RT-mPCR developed was sufficiently high, suggesting that this assay may be used for both diagnostic and surveillance testing. According to the RT-mPCR results, IPNV was not present in wild fish. These results support the hypothesis that the VHSV-Ie genotype, highly prevalent among fish species in the Black Sea, may have a serious impact on the population dynamics of wild fish stocks. PMID:24991737

  14. Sublethal concentrations of ichthyotoxic alga Prymnesium parvum affect rainbow trout susceptibility to viral haemorrhagic septicaemia virus.

    PubMed

    Andersen, Nikolaj Gedsted; Lorenzen, Ellen; Snogdal Boutrup, Torsten; Hansen, Per Juel; Lorenzen, Niels

    2016-01-13

    Ichthyotoxic algal blooms are normally considered a threat to maricultured fish only when blooms reach lethal cell concentrations. The degree to which sublethal algal concentrations challenge the health of the fish during blooms is practically unknown. In this study, we analysed whether sublethal concentrations of the ichthyotoxic alga Prymnesium parvum affect the susceptibility of rainbow trout Oncorhynchus mykiss to viral haemorrhagic septicaemia virus (VHSV). During exposure to sublethal algal concentrations, the fish increased production of mucus on their gills. When fish were exposed to the algae for 12 h prior to the addition of virus, a marginal decrease in the susceptibility to VHSV was observed compared to fish exposed to VHSV without algae. If virus and algae were added simultaneously, inclusion of the algae increased mortality by 50% compared to fish exposed to virus only, depending on the experimental setup. We concluded that depending on the local exposure conditions, sublethal concentrations of P. parvum could affect susceptibility of fish to infectious agents such as VHSV. PMID:26758652

  15. First isolation and genotyping of viruses from recent outbreaks of viral haemorrhagic septicaemia (VHS) in Slovenia.

    PubMed

    Toplak, Ivan; Hostnik, Peter; Rihtaric, Danijela; Olesen, Niels Jørgen; Skall, Helle Frank; Jencic, Vlasta

    2010-10-26

    In November and December 2007, the virus causing viral haemorrhagic septicaemia (VHS) was detected in rainbow trout Oncorhynchus mykiss from 2 fish farms in Slovenia. During 2008 and 2009 the infection spread only among rainbow trout farms and 4 new outbreaks were confirmed. High mortality and clinical signs of VHS were observed among the diseased fish. VHSV was confirmed by virus isolation, immunoperoxidase test, reverse transcriptase polymerase chain reaction (RT-PCR) and phylogenetic analysis. Based on 1 complete (1524 nucleotides [nt]) and 9 partial (600 nt) glycoprotein gene nucleotide sequences, 9 VHSV isolates from the 6 VHS outbreaks were genetically closely related (99 to 100% identity), and were classified into the Subgroup I-a of Genotype I, most closely related to the German isolates Dstg21-07, Dstg36-06, and Dstg54-1-07 (99 to 100% identity). Phylogenetic analysis and epidemiological investigations confirmed that the VHS virus had been (re)introduced with imported live fish, and that subsequent outbreaks were linked to the initial infection. Our study shows that direct nucleotide sequencing of RT-PCR products, amplified from the tissue of VHSV-infected fish, represents a reliable tool for fast routine genotyping in diagnostic laboratories. This is the first report of a natural epidemic associated with VHSV infection in Slovenia since the eradication of the disease in 1977. PMID:21166311

  16. Epidemiological aspects of viral haemorrhagic septicaemia virus genotype II isolated from Baltic herring, Clupea harengus membras L.

    PubMed

    Gadd, T; Jakava-Viljanen, M; Tapiovaara, H; Koski, P; Sihvonen, L

    2011-07-01

    This study was carried out to clarify the role of wild fish, especially Baltic herring, Clupea harengus membras L., in the epidemiology of viral haemorrhagic septicaemia virus (VHSV) in brackish water in Finland. Baltic herring with no visible signs of disease were collected from the Archipelago Sea, the Gulf of Bothnia and the eastern Gulf of Finland. In total, 7580 herring were examined by virus isolation as 758 pooled samples and 3029 wild salmonid broodfish as pooled samples during 2004-2006. VHSV was isolated from 51 pooled herring samples in bluegill fibroblast-2 cells, but not in epithelioma papulosum cyprini cells. The majority of isolations were from the coastal archipelago and from fish caught during the spawning season. Based on glycoprotein (G) gene sequences, the virus was classified as a member of genotype II of VHSV. Pairwise comparisons of the G gene regions of herring isolates revealed that all the isolates were closely related, with 98.8-100% nucleotide homology. Phylogenetic analyses revealed that they were closely related to the strains isolated previously from herring and sprat, Sprattus sprattus (L.), in Gotland and to the VHSV isolates from European river lamprey, Lampetra fluviatilis (L.), in the rivers that flow into the Bothnian Bay. The infection in Baltic herring is likely to be independent of the VHSV Id epidemic in farmed rainbow trout, Oncorhynchus mykiss (Walbaum).

  17. A mortality event in wrasse species (Labridae) associated with the presence of viral haemorrhagic septicaemia virus.

    PubMed

    Munro, E S; McIntosh, R E; Weir, S J; Noguera, P A; Sandilands, J M; Matejusova, I; Mayes, A S; Smith, R

    2015-04-01

    Viral haemorrhagic septicaemia (VHS) is an infectious disease of farmed and wild fish and has an extensive host range in both freshwater and marine environments. In December 2012, a wrasse population consisting of ballan, Labrus bergylta (Ascanius), corkwing, Symphodus melops (L.), cuckoo, Labrus mixtus L., goldsinny, Ctenolabrus rupestris (L.), and rock cook, Centrolabrus exoletus (L.), held at a marine hatchery in the Shetland Isles, Scotland, experienced a mortality event. Approximately 10 000 wrasse were being held at the facility on behalf of an Atlantic salmon, Salmo salar L., aquaculture company prior to being deployed for the biological control of parasites on marine pen Atlantic salmon, aquaculture sites. Fish Health Inspectors from Marine Scotland Science initiated a diagnostic investigation, and subsequent diagnostic testing confirmed the site to be VHSV positive by qRT-PCR and virus isolation followed by ELISA. A VHSV genotype-specific qRT-PCR assay revealed that the isolates belonged to genotype III, the European marine strain of the virus. The virus genotype was further confirmed by nucleic acid sequencing of the partial nucleoprotein (N) and glycoprotein (G) genes followed by BLAST nucleotide searches. This study reports for the first time the detection of VHSV within multiple wrasse species and highlights the need for a comprehensive risk-based approach to the use of wrasse and other finfish species as biological controls within the aquaculture industry.

  18. Oral transmission as a route of infection for viral haemorrhagic septicaemia virus in rainbow trout, Oncorhynchus mykiss (Walbaum).

    PubMed

    Schönherz, A A; Hansen, M H H; Jørgensen, H B H; Berg, P; Lorenzen, N; Einer-Jensen, K

    2012-06-01

    Surveys among wild marine fish have revealed occurrence of viral haemorrhagic septicaemia virus (VHSV) infections in a high number of diverse fish species. In marine aquaculture of rainbow trout, preying on invading wild fish might thus be a risk factor for introduction and adaptation of VHSV and subsequent disease outbreaks. Our objective was to determine whether an oral transmission route for VHSV in rainbow trout exists. Juvenile trout were infected through oral, waterborne and cohabitation transmission routes, using a recombinant virus strain harbouring Renilla luciferase as reporter gene. Viral replication in stomach and kidney tissue was detected through bioluminescence activity of luciferase and qRT-PCR. Replication was detected in both tissues, irrespective of transmission route. Replication patterns, however, differed among transmission routes. In trout infected through oral transmission, replication was detected in the stomach prior to kidney tissue. In trout infected through waterborne or cohabitation transmission, replication was detected in kidney prior to stomach or in both tissues simultaneously. We demonstrate the existence of an oral transmission route for VHSV in rainbow trout. This implies that preying on invading infected wild fish is a risk factor for introduction of VHSV into marine cultures of rainbow trout.

  19. Genotyping of the fish rhabdovirus, viral haemorrhagic septicaemia virus, by restriction fragment length polymorphisms

    USGS Publications Warehouse

    Einer-Jensen, Katja; Winton, James R.; Lorenzen, Niels

    2005-01-01

    The aim of this study was to develop a standardized molecular assay that used limited resources and equipment for routine genotyping of isolates of the fish rhabdovirus, viral haemorrhagic septicaemia virus (VHSV). Computer generated restriction maps, based on 62 unique full-length (1524 nt) sequences of the VHSV glycoprotein (G) gene, were used to predict restriction fragment length polymorphism (RFLP) patterns that were subsequently grouped and compared with a phylogenetic analysis of the G-gene sequences of the same set of isolates. Digestion of PCR amplicons from the full-lengthG-gene by a set of three restriction enzymes was predicted to accurately enable the assignment of the VHSV isolates into the four major genotypes discovered to date. Further sub-typing of the isolates into the recently described sub-lineages of genotype I was possible by applying three additional enzymes. Experimental evaluation of the method consisted of three steps: (i) RT-PCR amplification of the G-gene of VHSV isolates using purified viral RNA as template, (ii) digestion of the PCR products with a panel of restriction endonucleases and (iii) interpretation of the resulting RFLP profiles. The RFLP analysis was shown to approximate the level of genetic discrimination obtained by other, more labour-intensive, molecular techniques such as the ribonuclease protection assay or sequence analysis. In addition, 37 previously uncharacterised isolates from diverse sources were assigned to specific genotypes. While the assay was able to distinguish between marine and continental isolates of VHSV, the differences did not correlate with the pathogenicity of the isolates.

  20. Virus isolation vs RT-PCR: which method is more successful in detecting VHSV and IHNV in fish tissue sampled under field conditions?

    PubMed

    Knüsel, R; Bergmann, S M; Einer-Jensen, K; Casey, J; Segner, H; Wahli, T

    2007-09-01

    This study compared the results of reverse transcription-polymerase chain reaction (RT-PCR) and traditional virus isolation on cell culture in detection of viral haemorrhagic septicaemia virus (VHSV) and infectious haematopoietic necrosis virus (IHNV). RT-PCR was used for 172 tissue sample pools (total of 859 fish) originating from a field survey on the occurrence of VHSV and IHNV in farmed and wild salmonids in Switzerland. These samples represented all sites with fish that were either identified as virus-positive by means of virus isolation (three sites, four positive tissue sample pools) and/or demonstrated positive anti-VHSV-antibody titres (83 sites, 121 positive blood samples) in a serum plaque neutralization test (SPNT). The RT-PCR technique confirmed the four VHSV-positive tissue sample pools detected by virus isolation and additionally identified one VHSV-positive sample that showed positive anti-VHSV-AB titres, but was negative in virus isolation. With IHNV, RT-PCR detected two positive samples not identified by virus isolation while in these fish the SPNT result had been questionable. One of the IHNV-positive samples represents the first detection of IHNV-RNA in wild brown trout in Switzerland. Compared to SPNT, the RT-PCR method detected, as with virus isolation, a much lower number of positive cases; reasons for this discrepancy are discussed. Our results indicate that RT-PCR can not only be successfully applied in field surveys, but may also be slightly more sensitive than virus isolation. However, in a titration experiment under laboratory conditions, the sensitivity of RT-PCR was not significantly higher when compared with virus isolation.

  1. Viral load of various tissues of rainbow trout challenged with viral haemorrhagic septicaemia virus at various stages of disease.

    PubMed

    Oidtmann, B; Joiner, C; Stone, D; Dodge, M; Reese, R A; Dixon, P

    2011-01-21

    Market-sized rainbow trout Oncorhynchus mykiss were challenged by waterborne exposure to viral haemorrhagic septicaemia virus (VHSV isolate of genogroup Ia). Fish were sampled at 4 stages of infection (before onset of clinical signs, clinically affected fish, mortalities and survivors) and the viral load determined in (1) internal organs, (2) muscle tissue and (3) brain and gill tissue. Virus levels were determined by virus titration and real-time RT-PCR. VHSV was detected by either method in the majority of fish before onset of clinical signs and in the survivor group as well as in all fish in the clinically affected fish and mortality groups. Mean virus amounts per mg of tissue determined by virus titration (TCID50) or real-time RT-PCR (copy number) were > 10(4) in preclinical fish, > 10(3.8) in clinically affected fish, > 10(3.9) in mortalities and > 10(1.2) in survivors. Virus levels tended to be highest in the internal organs of subclinical and clinically affected fish and in brain and gill tissue of survivors. The results demonstrate that significant levels of VHSV can be found in tissues of rainbow trout that may be marketed for human consumption, which may have relevance for the biosecurity of VHS-free areas.

  2. Factors controlling the early stages of viral haemorrhagic septicaemia epizootics: Low exposure levels, virus amplification and fish-to-fish transmission

    USGS Publications Warehouse

    Hershberger, P.K.; Gregg, J.L.; Grady, C.A.; Hart, L.M.; Roon, S.R.; Winton, J.R.

    2011-01-01

    Viral haemorrhagic septicaemia virus, Genogroup IVa (VHSV), was highly infectious to Pacific herring, Clupea pallasii (Valenciennes), even at exposure doses occurring below the threshold of sensitivity for a standard viral plaque assay; however, further progression of the disease to a population-level epizootic required viral amplification and effective fish-to-fish transmission. Among groups of herring injected with VHSV, the prevalence of infection was dose-dependent, ranging from 100%, 75% and 38% after exposure to 19, 0.7 and 0.07 plaque-forming units (PFU)/fish, respectively. Among Pacific herring exposed to waterborne VHSV (140PFUmL-1), the prevalence of infection, geometric mean viral tissue titre and cumulative mortality were greater among cohabitated herring than among cohorts that were held in individual aquaria, where fish-to-fish transmission was prevented. Fish-to-fish transmission among cohabitated herring probably occurred via exposure to shed virus which peaked at 680PFUmL-1; shed virus was not detected in the tank water from any isolated individuals. The results provide insights into mechanisms that initiate epizootic cascades in populations of wild herring and have implications for the design of VHSV surveys in wild fish populations. ?? Published 2011. This article is a US Government work and is in the public domain in the USA.

  3. Comparison of treatments to inactivate viral hemorrhagic septicemia virus (VHSV-IVb) in frozen baitfish.

    PubMed

    Phelps, Nicholas B D; Goodwin, Andrew E; Marecaux, Emily; Goyal, Sagar M

    2013-02-28

    Current US state and federal fish health regulations target the spread of viral hemorrhagic septicemia virus-IVb (VHSV-IVb) through movement restrictions of live fish; however, they largely ignore the potential for the virus to be spread through commercial distribution and use of frozen baitfish from VHSV-IVb-positive regions. Some state laws do require treatment of frozen baitfish to inactivate VHSV, and additional methods have been proposed, but few scientific studies have examined the efficacy of these treatments. In this study, bluegills Lepomis macrochirus were challenged with VHSV-IVb and frozen to represent standard industry methods, disinfected by various treatments, and tested for infectious VHSV-IVb using virus isolation. The virus was isolated from 70% of fish subjected to 3 freeze/thaw cycles. All other treatment methods were effective in inactivating the virus, including treatment with isopropyl alcohol, mineral oil, salt and borax, and dehydration. Dehydration followed by rehydration is rapid and effective, and therefore, seems to be the best option for inactivating VHSV-IVb present in frozen baitfish while maintaining their usefulness as bait. PMID:23446970

  4. Comparison of treatments to inactivate viral hemorrhagic septicemia virus (VHSV-IVb) in frozen baitfish.

    PubMed

    Phelps, Nicholas B D; Goodwin, Andrew E; Marecaux, Emily; Goyal, Sagar M

    2013-02-28

    Current US state and federal fish health regulations target the spread of viral hemorrhagic septicemia virus-IVb (VHSV-IVb) through movement restrictions of live fish; however, they largely ignore the potential for the virus to be spread through commercial distribution and use of frozen baitfish from VHSV-IVb-positive regions. Some state laws do require treatment of frozen baitfish to inactivate VHSV, and additional methods have been proposed, but few scientific studies have examined the efficacy of these treatments. In this study, bluegills Lepomis macrochirus were challenged with VHSV-IVb and frozen to represent standard industry methods, disinfected by various treatments, and tested for infectious VHSV-IVb using virus isolation. The virus was isolated from 70% of fish subjected to 3 freeze/thaw cycles. All other treatment methods were effective in inactivating the virus, including treatment with isopropyl alcohol, mineral oil, salt and borax, and dehydration. Dehydration followed by rehydration is rapid and effective, and therefore, seems to be the best option for inactivating VHSV-IVb present in frozen baitfish while maintaining their usefulness as bait.

  5. Molecular characterization of the Great Lakes viral hemorrhagic septicemia virus (VHSV) isolate from USA

    PubMed Central

    Ammayappan, Arun; Vakharia, Vikram N

    2009-01-01

    Background Viral hemorrhagic septicemia virus (VHSV) is a highly contagious viral disease of fresh and saltwater fish worldwide. VHSV caused several large scale fish kills in the Great Lakes area and has been found in 28 different host species. The emergence of VHS in the Great Lakes began with the isolation of VHSV from a diseased muskellunge (Esox masquinongy) caught from Lake St. Clair in 2003. VHSV is a member of the genus Novirhabdovirus, within the family Rhabdoviridae. It has a linear single-stranded, negative-sense RNA genome of approximately 11 kbp, with six genes. VHSV replicates in the cytoplasm and produces six monocistronic mRNAs. The gene order of VHSV is 3'-N-P-M-G-NV-L-5'. This study describes molecular characterization of the Great Lakes VHSV strain (MI03GL), and its phylogenetic relationships with selected European and North American isolates. Results The complete genomic sequences of VHSV-MI03GL strain was determined from cloned cDNA of six overlapping fragments, obtained by RT-PCR amplification of genomic RNA. The complete genome sequence of MI03GL comprises 11,184 nucleotides (GenBank GQ385941) with the gene order of 3'-N-P-M-G-NV-L-5'. These genes are separated by conserved gene junctions, with di-nucleotide gene spacers. The first 4 nucleotides at the termini of the VHSV genome are complementary and identical to other novirhadoviruses genomic termini. Sequence homology and phylogenetic analysis show that the Great Lakes virus is closely related to the Japanese strains JF00Ehi1 (96%) and KRRV9822 (95%). Among other novirhabdoviruses, VHSV shares highest sequence homology (62%) with snakehead rhabdovirus. Conclusion Phylogenetic tree obtained by comparing 48 glycoprotein gene sequences of different VHSV strains demonstrate that the Great Lakes VHSV is closely related to the North American and Japanese genotype IVa, but forms a distinct genotype IVb, which is clearly different from the three European genotypes. Molecular characterization of the

  6. Effect of G gene-deleted recombinant viral hemorrhagic septicemia virus (rVHSV-ΔG) on the replication of wild type VHSV in a fish cell line and in olive flounder (Paralichthys olivaceus).

    PubMed

    Kim, Min Sun; Choi, Seung Hyuk; Kim, Ki Hong

    2016-07-01

    In an earlier study, we generated a replicon viral hemorrhagic septicemia virus (VHSV) particle that was lacking the G gene in the genome (rVHSV-ΔG), and proved the potential of it as a protective vaccine through the immunization of olive flounder (Paralichthys olivaceus) fingerlings. Safety is the most important preconsideration for the development of recombinant live vaccines, and a major concern of propagation-incompetent viral particles would be the possible harmful effect to hosts through the interaction with wild-type viruses. Thus, in the present study, we analyzed the replication of rVHSV-ΔG in the presence of wild-type VHSV and the effect of rVHSV-ΔG on the replication of wild-type VHSV in Epithelioma papulosum cyprini (EPC) cells and in olive flounder fingerlings. The replication of wild-type VHSV in EPC cells was severely suppressed when the MOI of rVHSV-ΔG was 0.1 or 0.01, on the other hand, the titers of rVHSV-ΔG were not increased and stayed in a relatively constant according to time lapse. Furthermore, the replication of other novirhabdoviruses, IHNV and HIRRV, was also inhibited by co-infection with high titers of rVHSV-ΔG. There were no big differences in mortalities between groups infected with wild-type VHSV plus rVHSV-ΔG and groups infected with wild-type VHSV alone, when the challenged wild-type VHSV was more than 10(2) PFU/fish. However, a group of fish infected with 10 PFU/fish of wild-type VHSV plus rVHSV-ΔG showed significantly lower and slowly progressing cumulative mortality than a group of fish infected with 10 PFU/fish of wild-type VHSV alone. This result suggests that rVHSV-ΔG has an ability to attenuate the disease progression caused by wild-type VHSV when co-infected with relatively low titers of wild-type VHSV. These results indicate that the propagation-incompetent rVHSV-ΔG would not worsen but attenuate the progression of a disease caused by wild-type VHSV infection. Therefore, rVHSV-ΔG-based vaccines can provide a

  7. Isolation of viral haemorrhagic septicaemia virus from muskellunge, Esox masquinongy (Mitchill), in Lake St Clair, Michigan, USA reveals a new sublineage of the North American genotype

    USGS Publications Warehouse

    Elsayed, E.; Faisal, M.; Thomas, M.; Whelan, G.; Batts, W.; Winton, J.

    2006-01-01

    Viral haemorrhagic septicaemia virus (VHSV) was isolated from muskellunge, Esox masquinongy (Mitchill), caught from the NW portion of Lake St Clair, Michigan, USA in 2003. Affected fish exhibited congestion of internal organs; the inner wall of the swim bladder was thickened and contained numerous budding, fluid-filled vesicles. A virus was isolated using fish cell lines inoculated with a homogenate of kidney and spleen tissues from affected fish. Focal areas of cell rounding and granulation appeared as early as 24 h post-inoculation and expanded rapidly to destroy the entire cell sheet by 96 h. Electron microscopy revealed virions that were 170-180 nm in length by 60-70 nm in width having a bullet-shaped morphology typical of rhabdoviruses. The virus was confirmed as VHSV by reverse transcriptase-polymerase chain reaction. Sequence analysis of the entire nucleoprotein and glycoprotein genes revealed the virus was a member of the North American genotype of VHSV; however, the isolate was sufficiently distinct to be considered a separate sublineage, suggesting its origin may have been from marine species inhabiting the eastern coastal areas of the USA or Canada. ?? 2006 Blackwell Publishing Ltd.

  8. Turbot (Scophthalmus maximus) vs. VHSV (Viral Hemorrhagic Septicemia Virus): A Review

    PubMed Central

    Pereiro, Patricia; Figueras, Antonio; Novoa, Beatriz

    2016-01-01

    Turbot (Scophthalmus maximus) is a very valuable fish species both in Europe and China. The culture of this flatfish is well-established but several bacteria, viruses, and parasites can produce mortality or morbidity episodes in turbot farms. Viral Hemorrhagic Septicemia Virus (VHSV) is one of the most threatening pathogens affecting turbot, because neither vaccines nor treatments are commercially available. Although the mortality in the turbot farms is relatively low, when this virus is detected all the stock have to be destroyed. The main goals that need to be improved in order to reduce the incidence of this disease is to know what are the strategies or molecules the host use to fight the virus and, in consequence, try to potentiate this response using different ways. Certain molecules can be selected as potential antiviral treatments because of their high protective effect against VHSV. On the other hand, the use of resistance markers for selective breeding is one of the most attractive approaches. This review englobes all the investigation concerning the immune interaction between turbot and VHSV, which until the last years was very scarce, and the knowledge about VHSV-resistance markers in turbot. Nowadays, the availability of abundant transcriptomic information and the recent sequencing of the turbot genome open the door to a more exhaustive and profuse investigation in these areas. PMID:27303308

  9. Turbot (Scophthalmus maximus) vs. VHSV (Viral Hemorrhagic Septicemia Virus): A Review.

    PubMed

    Pereiro, Patricia; Figueras, Antonio; Novoa, Beatriz

    2016-01-01

    Turbot (Scophthalmus maximus) is a very valuable fish species both in Europe and China. The culture of this flatfish is well-established but several bacteria, viruses, and parasites can produce mortality or morbidity episodes in turbot farms. Viral Hemorrhagic Septicemia Virus (VHSV) is one of the most threatening pathogens affecting turbot, because neither vaccines nor treatments are commercially available. Although the mortality in the turbot farms is relatively low, when this virus is detected all the stock have to be destroyed. The main goals that need to be improved in order to reduce the incidence of this disease is to know what are the strategies or molecules the host use to fight the virus and, in consequence, try to potentiate this response using different ways. Certain molecules can be selected as potential antiviral treatments because of their high protective effect against VHSV. On the other hand, the use of resistance markers for selective breeding is one of the most attractive approaches. This review englobes all the investigation concerning the immune interaction between turbot and VHSV, which until the last years was very scarce, and the knowledge about VHSV-resistance markers in turbot. Nowadays, the availability of abundant transcriptomic information and the recent sequencing of the turbot genome open the door to a more exhaustive and profuse investigation in these areas. PMID:27303308

  10. A novel multiplex RT-qPCR method based on dual-labelled probes suitable for typing all known genotypes of viral haemorrhagic septicaemia virus.

    PubMed

    Vázquez, D; López-Vázquez, C; Skall, H F; Mikkelsen, S S; Olesen, N J; Dopazo, C P

    2016-04-01

    Viral haemorrhagic septicaemia (VHS) is a notifiable fish disease, whose causative agent is a rhabdovirus isolated from a wide range of fish species, not only in fresh but also in marine and brackish waters. Phylogenetic studies have identified four major genotypes, with a strong geographical relationship. In this study, we have designed and validated a new procedure--named binary multiplex RT-qPCR (bmRT-qPCR)--for simultaneous detection and typing of all four genotypes of VHSV by real-time RT-PCR based on dual-labelled probes and composed by two multiplex systems designed for European and American/Asiatic isolates, respectively, using a combination of three different fluorophores. The specificity of the procedure was assessed by including a panel of 81 VHSV isolates covering all known genotypes and subtypes of the virus, and tissue material from experimentally infected rainbow trout, resulting in a correct detection and typing of all strains. The analytical sensitivity was evaluated in a comparative assay with titration in cell culture, observing that both methods provided similar limits of detection. The proposed method can be a powerful tool for epidemiological analysis of VHSV by genotyping unknown samples within a few hours.

  11. Comparative susceptibility among three stocks of yellow perch, Perca flavescens (Mitchill), to viral haemorrhagic septicaemia virus strain IVb from the Great Lakes.

    PubMed

    Olson, W; Emmenegger, E; Glenn, J; Winton, J; Goetz, F

    2013-08-01

    The Great Lakes strain of viral haemorrhagic septicaemia virus IVb (VHSV-IVb) is capable of infecting a wide number of naive species and has been associated with large fish kills in the Midwestern United States since its discovery in 2005. The yellow perch, Perca flavescens (Mitchill), a freshwater species commonly found throughout inland waters of the United States and prized for its high value in sport and commercial fisheries, is a species documented in several fish kills affiliated with VHS. In the present study, differences in survival after infection with VHSV IVb were observed among juvenile fish from three yellow perch broodstocks that were originally derived from distinct wild populations, suggesting innate differences in susceptibility due to genetic variance. While all three stocks were susceptible upon waterborne exposure to VHS virus infection, fish derived from the Midwest (Lake Winnebago, WI) showed significantly lower cumulative % survival compared with two perch stocks derived from the East Coast (Perquimans River, NC and Choptank River, MD) of the United States. However, despite differences in apparent susceptibility, clinical signs did not vary between stocks and included moderate-to-severe haemorrhages at the pelvic and pectoral fin bases and exophthalmia. After the 28-day challenge was complete, VHS virus was analysed in subsets of whole fish that had either survived or succumbed to the infection using both plaque assay and quantitative PCR methodologies. A direct correlation was identified between the two methods, suggesting the potential for both methods to be used to detect virus in a research setting. PMID:23305522

  12. Rainbow trout surviving infections of viral haemorrhagic septicemia virus (VHSV) show lasting antibodies to recombinant G protein fragments.

    PubMed

    Encinas, P; Gomez-Casado, E; Fregeneda-Grandes; Olesen, N J; Lorenzen, N; Estepa, A; Coll, J M

    2011-03-01

    Rainbow trout antibodies (Abs) binding to recombinant fragments (frgs) derived from the protein G of the viral haemorrhagic septicemia virus (VHSV)-07.71 strain, could be detected by ELISA (frg-ELISA) in sera from trout surviving laboratory-controlled infections. Abs were detected not only by using sera from trout infected with the homologous VHSV isolate but also with the VHSV-DK-201433 heterologous isolate, which had 13 amino acid changes. Sera from healthy trout and/or from trout surviving infectious haematopoietic necrosis virus (IHNV) infection, were used to calculate cut-off absorbances to differentiate negative from positive sera. Specific anti-VHSV Abs could then be detected by using any of the following frgs: frg11 (56-110), frg15 (65-250), frg16 (252-450) or G21-465. While high correlations were found among the ELISA values obtained with the different frgs, no correlations between any frg-ELISA and complement-dependent 50% plaque neutralization test (PNT) titres could be demonstrated. Between 4 and 10 weeks after VHSV infection, more trout sera were detected as positives by using heterologous frg-ELISA rather than homologous PNT. Furthermore, the percentage of positive sera detected by frg11-ELISA increased with time after infection to reach 100%, while those detected by complement-dependent PNT decreased to 29.4%, thus confirming that the lack of neutralizing Abs does not mean the lack of any anti-VHSV Abs in survivor trout sera. Preliminary results with sera from field samples suggest that further refinements of the frg-ELISA could allow detection of anti-VHSV trout Abs in natural outbreaks caused by different heterologous VHSV isolates. The homologous frg-ELISA method could be useful to follow G immunization attempts during vaccine development and/or to best understand the fish Ab response during VHSV infections. The viral frgs approach might also be used with other fish species and/or viruses.

  13. Temporary protection of rainbow trout gill epithelial cells from infection with viral haemorrhagic septicaemia virus IVb.

    PubMed

    Al-Hussinee, L; Pham, P H; Russell, S; Tubbs, L; Tafalla, C; Bols, N C; Dixon, B; Lumsden, J S

    2016-09-01

    The branchial epithelium is not only a primary route of entry for viral pathogens, but is also a site of viral replication and subsequent shedding may also occur from the gill epithelium. This study investigated the potential of agents known to stimulate innate immunity to protect rainbow trout epithelial cells (RTgill-W1) from infection with VHSV IVb. RTgill-W1 cells were pretreated with poly I:C, FuGENE(®) HD + poly I:C, lipopolysaccharide (LPS), LPS + poly I:C or heat-killed VHSV IVb and then infected with VHSV IVb 4 days later. Cytopathic effect (CPE) was determined at 2, 3, 4, 7 and 11 days post-infection. Virus in cells and supernatant was detected using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). All of the treatments delayed the onset of CPE (per cent of monolayer destruction), compared with untreated controls; however, killed VHSV or poly I:C combined with LPS was the most effective. Similarly, the detection of viral RNA in the supernatant was delayed, and the quantity was significantly (P < 0.05) reduced by all treatments with the exception of LPS alone (4 days). Unlike many of the other treatments, pretreatment of RTgill-W1 with heat-killed VHSV did not upregulate interferon 1, 2 or MX 1 gene expression.

  14. Inter-species transmission of viral hemorrhagic septicemia virus (VHSV) from turbot (Scophthalmus maximus) to rainbow trout (Onchorhynchus mykiss).

    PubMed

    Schönherz, Anna A; Lorenzen, Niels; Einer-Jensen, Katja

    2013-04-01

    Successful viral infection is a complex mechanism, involving many host-pathogen interactions that developed during coevolution of host and pathogen, and often result in host-species specificity. Nevertheless, many viruses are able to infect several host species and sporadically cross species barriers. The viral hemorrhagic septicemia virus (VHSV), a rhabdovirus with high economic impact on the aquaculture industry, has developed an exceptionally wide host range across marine and freshwater environments. Transmission of VHSV between host species therefore represents a potential risk for aquaculture, which currently is not addressed in biosecurity managements. The objective of this study was to investigate the inter-species transmission potential of VHSV and evaluate whether infected marine wild fish pose a potential risk on marine cultured rainbow trout. A cohabitation infection trial with turbot as donor and rainbow trout as recipient host species was conducted. Turbot were intraperitoneally injected with either a marine-adapted (MA) or a trout-adapted (TA) VHSV isolate and subsequently grouped with naïve rainbow trout. Both VHSV isolates were able to replicate and cause mortality in turbot, while only the TA isolate was able to cross the species barrier and infect rainbow trout with fatal outcome. The results demonstrate that a marine fish species can function as reservoir and transmitter of TA VHSV isolates.

  15. Molecular Evolution and Phylogeography of Co-circulating IHNV and VHSV in Italy

    PubMed Central

    Abbadi, Miriam; Fusaro, Alice; Ceolin, Chiara; Casarotto, Claudia; Quartesan, Rosita; Dalla Pozza, Manuela; Cattoli, Giovanni; Toffan, Anna; Holmes, Edward C.; Panzarin, Valentina

    2016-01-01

    Infectious haematopoietic necrosis virus (IHNV) and viral haemorrhagic septicaemia virus (VHSV) are the most important viral pathogens impacting rainbow trout farming. These viruses are persistent in Italy, where they are responsible for severe disease outbreaks (epizootics) that affect the profitability of the trout industry. Despite the importance of IHNV and VHSV, little is known about their evolution at a local scale, although this is likely to be important for virus eradication and control. To address this issue we performed a detailed molecular evolutionary and epidemiological analysis of IHNV and VHSV in trout farms from northern Italy. Full-length glycoprotein gene sequences of a selection of VHSV (n = 108) and IHNV (n = 89) strains were obtained. This revealed that Italian VHSV strains belong to sublineages Ia1 and Ia2 of genotype Ia and are distributed into 7 genetic clusters. In contrast, all Italian IHNV isolates fell within genogroup E, for which only a single genetic cluster was identified. More striking was that IHNV has evolved more rapidly than VHSV (mean rates of 11 and 7.3 × 10−4 nucleotide substitutions per site, per year, respectively), indicating that these viruses exhibit fundamentally different evolutionary dynamics. The time to the most recent common ancestor of both IHNV and VHSV was consistent with the first reports of these pathogens in Italy. By combining sequence data with epidemiological information it was possible to identify different patterns of virus spread among trout farms, in which adjacent facilities can be infected by either genetically similar or different viruses, and farms located in different water catchments can be infected by identical strains. Overall, these findings highlight the importance of combining molecular and epidemiological information to identify the determinants of IHN and VHS spread, and to provide data that is central to future surveillance strategies and possibly control.

  16. Molecular Evolution and Phylogeography of Co-circulating IHNV and VHSV in Italy

    PubMed Central

    Abbadi, Miriam; Fusaro, Alice; Ceolin, Chiara; Casarotto, Claudia; Quartesan, Rosita; Dalla Pozza, Manuela; Cattoli, Giovanni; Toffan, Anna; Holmes, Edward C.; Panzarin, Valentina

    2016-01-01

    Infectious haematopoietic necrosis virus (IHNV) and viral haemorrhagic septicaemia virus (VHSV) are the most important viral pathogens impacting rainbow trout farming. These viruses are persistent in Italy, where they are responsible for severe disease outbreaks (epizootics) that affect the profitability of the trout industry. Despite the importance of IHNV and VHSV, little is known about their evolution at a local scale, although this is likely to be important for virus eradication and control. To address this issue we performed a detailed molecular evolutionary and epidemiological analysis of IHNV and VHSV in trout farms from northern Italy. Full-length glycoprotein gene sequences of a selection of VHSV (n = 108) and IHNV (n = 89) strains were obtained. This revealed that Italian VHSV strains belong to sublineages Ia1 and Ia2 of genotype Ia and are distributed into 7 genetic clusters. In contrast, all Italian IHNV isolates fell within genogroup E, for which only a single genetic cluster was identified. More striking was that IHNV has evolved more rapidly than VHSV (mean rates of 11 and 7.3 × 10−4 nucleotide substitutions per site, per year, respectively), indicating that these viruses exhibit fundamentally different evolutionary dynamics. The time to the most recent common ancestor of both IHNV and VHSV was consistent with the first reports of these pathogens in Italy. By combining sequence data with epidemiological information it was possible to identify different patterns of virus spread among trout farms, in which adjacent facilities can be infected by either genetically similar or different viruses, and farms located in different water catchments can be infected by identical strains. Overall, these findings highlight the importance of combining molecular and epidemiological information to identify the determinants of IHN and VHS spread, and to provide data that is central to future surveillance strategies and possibly control. PMID:27602026

  17. Molecular Evolution and Phylogeography of Co-circulating IHNV and VHSV in Italy.

    PubMed

    Abbadi, Miriam; Fusaro, Alice; Ceolin, Chiara; Casarotto, Claudia; Quartesan, Rosita; Dalla Pozza, Manuela; Cattoli, Giovanni; Toffan, Anna; Holmes, Edward C; Panzarin, Valentina

    2016-01-01

    Infectious haematopoietic necrosis virus (IHNV) and viral haemorrhagic septicaemia virus (VHSV) are the most important viral pathogens impacting rainbow trout farming. These viruses are persistent in Italy, where they are responsible for severe disease outbreaks (epizootics) that affect the profitability of the trout industry. Despite the importance of IHNV and VHSV, little is known about their evolution at a local scale, although this is likely to be important for virus eradication and control. To address this issue we performed a detailed molecular evolutionary and epidemiological analysis of IHNV and VHSV in trout farms from northern Italy. Full-length glycoprotein gene sequences of a selection of VHSV (n = 108) and IHNV (n = 89) strains were obtained. This revealed that Italian VHSV strains belong to sublineages Ia1 and Ia2 of genotype Ia and are distributed into 7 genetic clusters. In contrast, all Italian IHNV isolates fell within genogroup E, for which only a single genetic cluster was identified. More striking was that IHNV has evolved more rapidly than VHSV (mean rates of 11 and 7.3 × 10(-4) nucleotide substitutions per site, per year, respectively), indicating that these viruses exhibit fundamentally different evolutionary dynamics. The time to the most recent common ancestor of both IHNV and VHSV was consistent with the first reports of these pathogens in Italy. By combining sequence data with epidemiological information it was possible to identify different patterns of virus spread among trout farms, in which adjacent facilities can be infected by either genetically similar or different viruses, and farms located in different water catchments can be infected by identical strains. Overall, these findings highlight the importance of combining molecular and epidemiological information to identify the determinants of IHN and VHS spread, and to provide data that is central to future surveillance strategies and possibly control. PMID:27602026

  18. Comparative susceptibility among three stocks of yellow perch, Perca flavescens (Mitchill), to viral haemorrhagic septicaemia virus strain IVb from the Great Lakes

    USGS Publications Warehouse

    Olson, W.; Emmenegger, E.; Glenn, J.; Winton, J.; Goetz, F.

    2013-01-01

    The Great Lakes strain of viral haemorrhagic septicaemia virus IVb (VHSV-IVb) is capable of infecting a wide number of naive species and has been associated with large fish kills in the Midwestern United States since its discovery in 2005. The yellow perch, Perca flavescens (Mitchill), a freshwater species commonly found throughout inland waters of the United States and prized for its high value in sport and commercial fisheries, is a species documented in several fish kills affiliated with VHS. In the present study, differences in survival after infection with VHSV IVb were observed among juvenile fish from three yellow perch broodstocks that were originally derived from distinct wild populations, suggesting innate differences in susceptibility due to genetic variance. While all three stocks were susceptible upon waterborne exposure to VHS virus infection, fish derived from the Midwest (Lake Winnebago, WI) showed significantly lower cumulative % survival compared with two perch stocks derived from the East Coast (Perquimans River, NC and Choptank River, MD) of the United States. However, despite differences in apparent susceptibility, clinical signs did not vary between stocks and included moderate-to-severe haemorrhages at the pelvic and pectoral fin bases and exophthalmia. After the 28-day challenge was complete, VHS virus was analysed in subsets of whole fish that had either survived or succumbed to the infection using both plaque assay and quantitative PCR methodologies. A direct correlation was identified between the two methods, suggesting the potential for both methods to be used to detect virus in a research setting.

  19. Early Immune Responses in Rainbow Trout Liver upon Viral Hemorrhagic Septicemia Virus (VHSV) Infection

    PubMed Central

    Castro, Rosario; Abós, Beatriz; Pignatelli, Jaime; von Gersdorff Jørgensen, Louise; González Granja, Aitor; Buchmann, Kurt; Tafalla, Carolina

    2014-01-01

    Among the essential metabolic functions of the liver, in mammals, a role as mediator of systemic and local innate immunity has also been reported. Although the presence of an important leukocyte population in mammalian liver is well documented, the characterization of leukocyte populations in the teleost liver has been only scarcely addressed. In the current work, we have confirmed the presence of IgM+, IgD+, IgT+, CD8α+, CD3+ cells, and cells expressing major histocompatibility complex (MHC-II) in rainbow trout (Oncorhynchus mykiss) liver by flow cytometry and/or immunohistochemistry analysis. Additionally, the effect of viral hemorrhagic septicemia virus (VHSV) on the liver immune response was assessed. First, we studied the effect of viral intraperitoneal injection on the transcription of a wide selection of immune genes at days 1, 2 and 5 post-infection. These included a group of leukocyte markers genes, pattern recognition receptors (PRRs), chemokines, chemokine receptor genes, and other genes involved in the early immune response and in acute phase reaction. Our results indicate that T lymphocytes play a key role in the initial response to VHSV in the liver, since CD3, CD8, CD4, perforin, Mx and interferon (IFN) transcription levels were up-regulated in response to VHSV. Consequently, flow cytometry analysis of CD8α+ cells in liver and spleen at day 5 post-infection revealed a decrease in the number of CD8α+ cells in the spleen and an increased population in the liver. No differences were found however in the percentages of B lymphocyte (IgM+ or IgD+) populations. In addition, a strong up-regulation in the transcription levels of several PRRs and chemokines was observed from the second day of infection, indicating an important role of these factors in the response of the liver to viral infections. PMID:25338079

  20. European freshwater VHSV genotype Ia isolates divide into two distinct subpopulations.

    PubMed

    Kahns, S; Skall, H F; Kaas, R S; Korsholm, H; Bang Jensen, B; Jonstrup, S P; Dodge, M J; Einer-Jensen, K; Stone, D; Olesen, N J

    2012-05-15

    Viral haemorrhagic septicaemia (VHS), caused by the novirhabdovirus VHSV, often leads to significant economic losses to European rainbow trout production. The virus isolates are divided into 4 distinct genotypes with additional subgroups including sublineage Ia, isolates of which are the main source of outbreaks in European rainbow trout farming. A significant portion of Danish rainbow trout farms have been considered endemically infected with VHSV since the first disease outbreak was observed in the 1950s. However, following a series of sanitary programs starting in 1965, VHSV has not been detected in Denmark since January 2009. Full-length G-genes of all Danish VHSV isolates that were submitted for diagnostic analyses in the period 2004-2009 were sequenced and analysed. All 58 Danish isolates from rainbow trout grouped with sublineage Ia isolates. Furthermore, VHSV isolates from infected Danish freshwater catchments appear to have evolved into a distinct clade within sublineage Ia, herein designated clade Ia-1, whereas trout isolates originating from other continental European countries cluster in another distinct clade, designated clade Ia-2. In addition, phylogenetic analyses indicate that VHSV Ia-1 strains have caused a few outbreaks in Germany and the UK. It is likely that viruses have been transmitted from infected site(s) out of the Danish environment, although a direct transmission pathway has not been identified. Furthermore, VHSV Ia-2 isolates seem to have been transmitted to Denmark at least once. Interestingly, one viral isolate possibly persisted in a Danish watershed for nearly 4 yr without detection whereas other subclades of VHSV isolates appear to have been eliminated, probably because of implemented eradication procedures. PMID:22585300

  1. Isolation and identification of viral hemorrhagic septicemia virus (VHSV) from farmed rainbow trout (Oncorhynchus mykiss) in Iran.

    PubMed

    Ahmadivand, Sohrab; Soltani, Mehdi; Mardani, Karim; Shokrpoor, Sara; Rahmati-Holasoo, Hooman; Mokhtari, Abbas; Hasanzadeh, Reza

    2016-04-01

    Viral hemorrhagic septicemia virus (VHSV) is a rhabdovirus that causes one of the most important fish diseases in rainbow trout (Oncorhynchus mykiss) production industry. During the present study from October 2014 to July 2015, the virus causing viral hemorrhagic septicemia (VHS) was isolated and identified in rainbow trout farms from five of sixteen farms experiencing mass mortalities in six provinces of Iran with major trout production. Cumulative mortalities at VHSV-positive farms ranged from 30 to 70%. Clinical signs of disease included exophthalmia, petechial hemorrhages in the mandible and around the eyes, a swollen abdomen and darkening of the integument, widespread petechiae of the musculature and pyloric regions, severe congestion of the kidney, and pale enlarged livers. In addition, histopathologic examinations of tissues showed severe lesions in muscle, kidney and liver, which were compatible with those already described for VHS. Furthermore, homogenates tissues of diseased fish induced cytopathic effects (CPE) in CHSE-214 cells, and confirmatory diagnosis of VHS was made by RT-PCR reactions. To our knowledge, this is the first report of isolation and identification of VHSV from farmed trout in Iran, which may have originated from Europe.

  2. An outbreak of VHSV (viral hemorrhagic septicemia virus) infection in farmed Japanese flounder Paralichthys olivaceus in Japan.

    PubMed

    Isshik, T; Nishizawa, T; Kobayashi, T; Nagano, T; Miyazaki, T

    2001-11-01

    A rhabdoviral disease occurred in farmed populations of market sized Japanese flounder (hirame) Paralichthys olivaceus in the Seto Inland Sea of Japan in 1996. The causative agent was identified as viral hemorrhagic septicemia virus (VHSV) based on morphological, immunological, and genetic analyses. Diseased fish that were artificially injected with a representative virus isolate showed the same pathological signs and high mortality as observed in the natural outbreak. This is the first report of an outbreak of VHSV infection in cultured fish in Japan. Clinical signs of diseased fish included dark body coloration, an expanded abdomen due to ascites, congested liver, splenomegaly, and a swollen kidney. Myocardial necrosis was most prominent and accompanied by inflammatory reactions. Necrotic lesions also occurred in the liver, spleen and hematopoietic tissue, and were accompanied by circulatory disturbances due to cardiac failure. Hemorrhagic lesions did not always appear in the lateral musculature. Transmission electron microscopy revealed many rhabdovirus particles and associated inclusion bodies containing nucleocapsids in the necrotized myocardium. The histopathological findings indicated that the necrotizing myocarditis could be considered a pathognomonic sign of VHSV infection in Japanese flounder. PMID:11775799

  3. Virulence of viral hemorrhagic septicemia virus (VHSV) genotypes Ia, IVa, IVb, and IVc in five fish species.

    PubMed

    Emmenegger, Eveline J; Moon, Chang Hoon; Hershberger, Paul K; Kurath, Gael

    2013-12-12

    The susceptibility of yellow perch Perca flavescens, rainbow trout Oncorhynchus mykiss, Chinook salmon O. tshawytscha, koi Cyprinus carpio koi, and Pacific herring Clupea pallasii to 4 strains of viral hemorrhagic septicemia virus (VHSV) was assessed. Fish were challenged via intraperitoneal injection with high (1 × 106 plaque-forming units, PFU) and low (1 × 103 PFU) doses of a European strain (genotype Ia), and North American strains from the West coast (genotype IVa), Great Lakes (genotype IVb), and the East coast (genotype IVc). Pacific herring were exposed to the same VHSV strains, but at a single dose of 5 × 103 PFU ml-1 by immersion in static seawater. Overall, yellow perch were the most susceptible, with cumulative percent mortality (CPM) ranging from 84 to 100%, and 30 to 93% in fish injected with high or low doses of virus, respectively. Rainbow trout and Chinook salmon experienced higher mortalities (47 to 98% CPM) after exposure to strain Ia than to the other virus genotypes. Pacific herring were most susceptible to strain IVa with an average CPM of 80% and moderately susceptible (42 to 52% CPM) to the other genotypes. Koi had very low susceptibility (≤5.0% CPM) to all 4 VHSV strains. Fish tested at 7 d post challenge were positive for all virus strains, with yellow perch having the highest prevalence and concentrations of virus, and koi the lowest. While genotype Ia had higher virulence in salmonid species, there was little difference in virulence or host-specificity between isolates from subtypes IVa, IVb, and IVc.

  4. Virulence of viral hemorrhagic septicemia virus (VHSV) genotypes Ia, IVa, IVb, and IVc in five fish species.

    USGS Publications Warehouse

    Emmenegger, Eveline J.; Moon, Chang Hoon; Hershberger, Paul K.; Kurath, Gael

    2013-01-01

    The susceptibility of yellow perch Perca flavescens, rainbow trout Oncorhynchus mykiss, Chinook salmon O. tshawytscha, koi Cyprinus carpio koi, and Pacific herring Clupea pallasii to 4 strains of viral hemorrhagic septicemia virus (VHSV) was assessed. Fish were challenged via intraperitoneal injection with high (1 × 106 plaque-forming units, PFU) and low (1 × 103 PFU) doses of a European strain (genotype Ia), and North American strains from the West coast (genotype IVa), Great Lakes (genotype IVb), and the East coast (genotype IVc). Pacific herring were exposed to the same VHSV strains, but at a single dose of 5 × 103 PFU ml-1 by immersion in static seawater. Overall, yellow perch were the most susceptible, with cumulative percent mortality (CPM) ranging from 84 to 100%, and 30 to 93% in fish injected with high or low doses of virus, respectively. Rainbow trout and Chinook salmon experienced higher mortalities (47 to 98% CPM) after exposure to strain Ia than to the other virus genotypes. Pacific herring were most susceptible to strain IVa with an average CPM of 80% and moderately susceptible (42 to 52% CPM) to the other genotypes. Koi had very low susceptibility (≤5.0% CPM) to all 4 VHSV strains. Fish tested at 7 d post challenge were positive for all virus strains, with yellow perch having the highest prevalence and concentrations of virus, and koi the lowest. While genotype Ia had higher virulence in salmonid species, there was little difference in virulence or host-specificity between isolates from subtypes IVa, IVb, and IVc.  

  5. Stability and efficacy of the 3'-UTR A4G-G5A variant of viral hemorrhagic septicemia virus (VHSV) as a live attenuated immersion VHSV vaccine in olive flounder (Paralichthys olivaceus).

    PubMed

    Kim, Sung-Hyun; Kim, Meesun; Choi, Go-Eun; Lee, Jeong Ho; Kang, Jung-Ha; Evensen, Øystein; Lee, Woo-Jai

    2016-02-17

    Viral hemorrhagic septicemia virus (VHSV) is the causative agent of viral hemorrhagic septicemia in fish, a disease that affects a number of teleost fish species including olive flounder (Paralichthys olivaceus). In this study, we assessed the safety and efficacy of two recombinant attenuated VHSV strains, termed A4G-G5A and ΔNV, with the purpose to select the most suitable vaccine strain. The virus strains were passaged in two commercially available cell lines, EPC and RTG-2, and the strains were also tested for residual virulence in zebrafish (Danio rerio). The A4G-G5A strain showed an attenuated growth profile in both the EPC and RTG-2 cell lines compared to wild-type (WT) VHSV (JF-09, genotype IVa), whereas the growth profile of ΔNV was comparable to the WT strains in RTG-2 cells in contrast to EPC cells. Moreover, ΔNV had higher residual virulence compared to A4G-G5A and was highly pathogenic to zebrafish. The A4G-G5A strain was chosen as vaccine candidate and tested for efficacy in in vivo fish studies in the target species, olive flounder, using an immersion vaccine scheme. Groups of fish were immunized with 10(2.5), 10(3.5), 10(4.5), and 10(5.5) TCID50/ml of A4G-G5A giving 5-13.3 cumulative percent mortality (CPM) post immunization. Immunization was followed by a challenge experiment using VHSV-WT. The relative percent survival (RPS) in immunized groups ranged from 81.6% to 100%, correlating with vaccination dose. This study demonstrates that while strain A4G-G5A has retained some residual virulence it confers high level of protection in immunized olive flounder. PMID:26772633

  6. Accurate detection and quantification of the fish viral hemorrhagic septicemia virus (VHSv) with a two-color fluorometric real-time PCR assay

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Viral Hemorrhagic Septicemia virus (VHSv) is one of the world's most serious fish pathogens, infecting > 80 marine, freshwater, and estuarine fish species from Eurasia and North America. A novel and especially virulent strain - IVb - appeared in the Great Lakes in 2003, killed many game fish species...

  7. A new StaRT-PCR approach to detect and quantify fish viral hemorrhagic septicemia virus (VHSv): enhanced quality control with internal standards

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Viral Hemorrhagic Septicemia virus (VHSv) causes one of the world’s most important finfish diseases, killing >80 species across Eurasia and North America. A new and especially virulent strain (IVb) emerged in the North American Great Lakes in 2003, threatening fisheries, baitfish, and aquaculture in...

  8. Development of an oral vaccine for immunisation of rainbow trout (Oncorhynchus mykiss) against viral haemorrhagic septicaemia.

    PubMed

    Adelmann, Malte; Köllner, Bernd; Bergmann, Sven M; Fischer, Uwe; Lange, Bodo; Weitschies, Werner; Enzmann, Peter-Joachim; Fichtner, Dieter

    2008-02-01

    In the European Union Viral Haemorrhagic Septicaemia (VHS) eradication is still based on stamping out. Due to the lack of effective low cost vaccines immune prophylaxis is currently not used to combat VHS. This paper describes a new oral delivery method for immunisation of trout with attenuated virus. The vaccine consists of lyophilised virus surrounded by polyethylene glycol (PEG) and was extruded under low temperature. In the stomach of trout, the use of additional neutralising and adsorbing bases resulted in a neutral pH around the vaccine pellets, thus protecting the antigen against gastric acid. The in vivo efficacy of this delivery method was examined in three animal challenge experiments using an attenuated VHS virus (VHSV) strain as a vaccine. After vaccination, VHSV mRNA in gut, heart, kidney, spleen and blood was amplified by semi-nested PCR after RT-PCR. Indirect immune fluorescence test detected VHS vaccine virus in the gut. The expression of MHC class II, CD4 and CD8alpha mRNAs after oral vaccination was measured in gut using real-time RT-PCR. Antibody levels were measured by ELISA one week before vaccination and five weeks after vaccination. Animals were challenged six weeks after vaccination with highly virulent VHSV and mortality was recorded. The experiments showed that orally delivered vaccine virus was released from the vaccine preparation, penetrated the gut mucosa and led to higher expression levels of MHC class II and CD4 mRNAs when compared to control guts. VHSV antibodies were detected after oral vaccination. Immunisation with this new vaccine formulation was followed by a significant protection against VHSV. While the cumulative mortality in the non-vaccinated control group reached 70%, more than 75% of the orally vaccinated fish were protected upon challenge. PMID:18191880

  9. Larval Pacific herring, Clupea pallasii (Valenciennes), are highly susceptible to viral haemorrhagic septicaemia and survivors are partially protected after their metamorphosis to juveniles

    USGS Publications Warehouse

    Hershberger, P.K.; Gregg, J.; Pacheco, C.; Winton, J.; Richard, J.; Traxler, G.

    2007-01-01

    Pacific herring were susceptible to waterborne challenge with viral haemorrhagic septicaemia virus (VHSV) throughout their early life history stages, with significantly greater cumulative mortalities occurring among VHSV-exposed groups of 9-, 44-, 54- and 76-day-old larvae than among respective control groups. Similarly, among 89-day-1-year-old and 1+year old post-metamorphosed juveniles, cumulative mortality was significantly greater in VHSV-challenged groups than in respective control groups. Larval exposure to VHSV conferred partial protection to the survivors after their metamorphosis to juveniles as shown by significantly less cumulative mortalities among juvenile groups that survived a VHS epidemic as larvae than among groups that were previously nai??ve to VHSV. Magnitude of the protection, measured as relative per cent survival, was a direct function of larval age at first exposure and was probably a reflection of gradual developmental onset of immunocompetence. These results indicate the potential for easily overlooked VHS epizootics among wild larvae in regions where the virus is endemic and emphasize the importance of early life history stages of marine fish in influencing the ecological disease processes. ?? 2007 The Authors.

  10. The use of a one-step real-time reverse transcription polymerase chain reaction (rRT-PCR) for the surveillance of viral hemorrhagic septicemia virus (VHSV) in Minnesota.

    PubMed

    Phelps, Nicholas B D; Patnayak, Devi P; Jiang, Yin; Goyal, Sagar M

    2012-12-01

    Viral hemorrhagic septicemia virus (VHSV) is a highly contagious and pathogenic virus of fish. The virus infects more than 70 fish species worldwide, in both fresh and salt water. A new viral strain (VHSV-IVb) has proven both virulent and persistent, spreading throughout the Great Lakes of North America and to inland water bodies in the region. To better understand the geographic distribution of the virus, we used a modified real-time reverse transcription polymerase chain reaction (rRT-PCR) assay for high-throughput testing of fish for VHSV. The assay was shown to be twice as sensitive as the gold standard, virus isolation, and did not cross react with other viruses found in fish. In addition, the diagnostic turnaround time was reduced from 28 to 30 d for virus isolation to 2-4 d for rRT-PCR. To demonstrate the usefulness of the rRT-PCR assay, 115 high-priority water bodies in Minnesota were tested by both methods from April 2010 to June 2011. All survey sites tested negative for VHSV by both methods. The survey results have informed fisheries managers on the absence of VHSV in Minnesota and have better prepared them for the eventual arrival of the disease. In addition, the results demonstrate the value of this rRT-PCR as a surveillance tool to rapidly identify an outbreak so that it can be controlled in a timely manner.

  11. Survival of the North American strain of viral hemorrhagic septicemia virus (VHSV) in filtered seawater and seawater containing ovarian fluid, crude oil and serum-enriched culture medium

    USGS Publications Warehouse

    Kocan, R.M.; Hershberger, P.K.; Elder, N.E.

    2001-01-01

     The North American strain of viral hemorrhagic septicemia virus (NA-VHSV) could be recovered for up to 40 h in natural filtered seawater (27 ppt) with a 50% loss of infectivity after approximately 10 h at 15°C. Addition of 10 ppb North Slope crude oil to the seawater had no effect on virus survival. However, when various concentrations of teleost ovarian fluid were added to seawater, virus could be recovered after 72 h at 0.01% ovarian fluid and after 96 h at 1.0%. When cell culture medium supplemented with 10% fetal bovine serum was added to the seawater, 100% of the virus could be recovered for the first 15 d and 60% of the virus remained after 36 d. These findings quantify NA-VHSV infectivity in natural seawater and demonstrate that ovarian fluid, which occurs naturally during spawning events, significantly prolongs the survival and infectivity of the virus. The extended stabilization of virus in culture medium supplemented with serum allows for low titer field samples to be collected and transported in an unfrozen state without significant loss of virus titer.

  12. Survival of the North American strain of viral hemorrhagic septicemia virus (VHSV) in filtered seawater and seawater containing ovarian fluid, crude oil and serum-enriched culture medium.

    PubMed

    Kocan, R M; Hershberger, P K; Elder, N E

    2001-01-26

    The North American strain of viral hemorrhagic septicemia virus (NA-VHSV) could be recovered for up to 40 h in natural filtered seawater (27 ppt) with a 50% loss of infectivity after approximately 10 h at 15 degrees C. Addition of 10 ppb North Slope crude oil to the seawater had no effect on virus survival. However, when various concentrations of teleost ovarian fluid were added to seawater, virus could be recovered after 72 h at 0.01% ovarian fluid and after 96 h at 1.0%. When cell culture medium supplemented with 10% fetal bovine serum was added to the seawater, 100% of the virus could be recovered for the first 15 d and 60% of the virus remained after 36 d. These findings quantify NA-VHSV infectivity in natural seawater and demonstrate that ovarian fluid, which occurs naturally during spawning events, significantly prolongs the survival and infectivity of the virus. The extended stabilization of virus in culture medium supplemented with serum allows for low titer field samples to be collected and transported in an unfrozen state without significant loss of virus titer.

  13. Induction of anti-viral genes during acute infection with Viral hemorrhagic septicemia virus (VHSV) genogroup IVa in Pacific herring (Clupea pallasii)

    USGS Publications Warehouse

    Hansen, John D.; Woodson, James C.; Hershberger, Paul K.; Grady, Courtney; Gregg, Jacob L.; Purcell, Maureen K.

    2012-01-01

    Infection with the aquatic rhabdovirus Viral hemorrhagic septicemia virus (VHSV) genogroup IVa results in high mortality in Pacific herring (Clupea pallasii) and is hypothesized to be a potential limiting factor for herring recovery. To investigate anti-viral immunity in the Pacific herring, four immune response genes were identified: the myxovirus resistance (Clpa-Mx), a major histocompatibility complex IB (named Clpa-UAA.001), the inducible immunoproteosome subunit 9 (Clpa-PSMB9) and the neutrophil chemotactic factor (Clpa-LECT2). Reverse transcriptase quantitative PCR (RT-qPCR) assays were developed based on these gene sequences to investigate the host immune response to acute VHSV infection following both injection and immersion challenge. Virus levels were measured by both plaque assay and RT-qPCR and peaked at day 6 during the 10-day exposure period for both groups of fish. The interferon stimulated genes (Clpa-Mx, −UAA.001, and −PSMB9) were significantly up-regulated in response to VHSV infection at both 6 and 10 days post-infection in both spleen and fin. Results from this study indicate that Pacific herring mount a robust, early antiviral response in both fin and spleen tissues. The immunological tools developed in this study will be useful for future studies to investigate antiviral immunity in Pacific herring.

  14. Induction of anti-viral genes during acute infection with Viral hemorrhagic septicemia virus (VHSV) genogroup IVa in Pacific herring (Clupea pallasii).

    PubMed

    Hansen, John D; Woodson, James C; Hershberger, Paul K; Grady, Courtney; Gregg, Jacob L; Purcell, Maureen K

    2012-02-01

    Infection with the aquatic rhabdovirus Viral hemorrhagic septicemia virus (VHSV) genogroup IVa results in high mortality in Pacific herring (Clupea pallasii) and is hypothesized to be a potential limiting factor for herring recovery. To investigate anti-viral immunity in the Pacific herring, four immune response genes were identified: the myxovirus resistance (Clpa-Mx), a major histocompatibility complex IB (named Clpa-UAA.001), the inducible immunoproteosome subunit 9 (Clpa-PSMB9) and the neutrophil chemotactic factor (Clpa-LECT2). Reverse transcriptase quantitative PCR (RT-qPCR) assays were developed based on these gene sequences to investigate the host immune response to acute VHSV infection following both injection and immersion challenge. Virus levels were measured by both plaque assay and RT-qPCR and peaked at day 6 during the 10-day exposure period for both groups of fish. The interferon stimulated genes (Clpa-Mx, -UAA.001, and -PSMB9) were significantly up-regulated in response to VHSV infection at both 6 and 10 days post-infection in both spleen and fin. Results from this study indicate that Pacific herring mount a robust, early antiviral response in both fin and spleen tissues. The immunological tools developed in this study will be useful for future studies to investigate antiviral immunity in Pacific herring.

  15. A survey of wild marine fish identifies a potential origin of an outbreak of viral haemorrhagic septicaemia in wrasse, Labridae, used as cleaner fish on marine Atlantic salmon, Salmo salar L., farms.

    PubMed

    Wallace, I S; Donald, K; Munro, L A; Murray, W; Pert, C C; Stagg, H; Hall, M; Bain, N

    2015-06-01

    Viral haemorrhagic septicaemia virus (VHSV) was isolated from five species of wrasse (Labridae) used as biological controls for parasitic sea lice predominantly, Lepeophtheirus salmonis (Krøyer, 1837), on marine Atlantic salmon, Salmo salar L., farms in Shetland. As part of the epidemiological investigation, 1400 wild marine fish were caught and screened in pools of 10 for VHSV using virus isolation. Eleven pools (8%) were confirmed VHSV positive from: grey gurnard, Eutrigla gurnardus L.; Atlantic herring, Clupea harengus L.; Norway pout, Trisopterus esmarkii (Nilsson); plaice, Pleuronectes platessa L.; sprat, Sprattus sprattus L. and whiting, Merlangius merlangus L. The isolation of VHSV from grey gurnard is the first documented report in this species. Nucleic acid sequencing of the partial nucleocapsid (N) and glycoprotein (G) genes was carried out for viral characterization. Sequence analysis confirmed that all wild isolates were genotype III the same as the wrasse and there was a close genetic similarity between the isolates from wild fish and wrasse on the farms. Infection from these local wild marine fish is the most likely source of VHSV isolated from wrasse on the fish farms.

  16. Accurate Detection and Quantification of the Fish Viral Hemorrhagic Septicemia virus (VHSv) with a Two-Color Fluorometric Real-Time PCR Assay

    PubMed Central

    Palsule, Vrushalee V.; Yeo, Jiyoun; Shepherd, Brian S.; Crawford, Erin L.; Stepien, Carol A.

    2013-01-01

    Viral Hemorrhagic Septicemia virus (VHSv) is one of the world's most serious fish pathogens, infecting >80 marine, freshwater, and estuarine fish species from Eurasia and North America. A novel and especially virulent strain – IVb – appeared in the Great Lakes in 2003, has killed many game fish species in a series of outbreaks in subsequent years, and shut down interstate transport of baitfish. Cell culture is the diagnostic method approved by the USDA-APHIS, which takes a month or longer, lacks sensitivity, and does not quantify the amount of virus. We thus present a novel, easy, rapid, and highly sensitive real-time quantitative reverse transcription PCR (qRT-PCR) assay that incorporates synthetic competitive template internal standards for quality control to circumvent false negative results. Results demonstrate high signal-to-analyte response (slope = 1.00±0.02) and a linear dynamic range that spans seven orders of magnitude (R2 = 0.99), ranging from 6 to 6,000,000 molecules. Infected fishes are found to harbor levels of virus that range to 1,200,000 VHSv molecules/106 actb1 molecules with 1,000 being a rough cut-off for clinical signs of disease. This new assay is rapid, inexpensive, and has significantly greater accuracy than other published qRT-PCR tests and traditional cell culture diagnostics. PMID:23977162

  17. Efficacy of a glycoprotein DNA vaccine against viral haemorrhagic septicaemia (VHS) in Pacific herring, Clupea pallasii Valenciennes

    USGS Publications Warehouse

    Hart, L.M.; Lorenzen, Niels; LaPatra, S.E.; Grady, C.A.; Roon, S.E.; O’Reilly, J.; Gregg, J.L.; Hershberger, P.K.

    2012-01-01

    Viral haemorrhagic septicaemia virus (VHSV) and its associated disease state, viral haemorrhagic septicaemia (VHS), is hypothesized to be a proximate factor accounting for the decline and failed recovery of Pacific herring populations in Prince William Sound, AK (Marty et al. 1998, 2003, 2010). Survivors of laboratory-induced VHSV epizootics develop resistance to subsequent viral exposure (Kocan et al. 2001; Hershberger et al. 2007, 2010), which is likely the result of immune system recognition of the viral glycoprotein (G) (Lecocq-Xhonneux et al. 1994), a surface antigen that contains neutralizing epitopes (Lorenzen, Olesen & Jorgensen 1990; Jørgensen et al. 1995) and cell attachment domains (Lecocq-Xhonneux et al. 1994; Estepa & Coll 1996). These properties have proven useful in the development of G-gene-based DNA vaccines for VHSV and a related rhabdovirus, infectious haematopoietic necrosis virus (IHNV) (Anderson et al. 1996; Heppell et al. 1998; Corbeil et al. 1999; Einer-Jensen et al. 2009). Rainbow trout fingerlings, Oncorhynchus mykiss (Walbaum), vaccinated with 1 µg of either the VHS or IHN vaccine are protected from VHS when exposed to virus as early as 4 days (44 degree days) post-vaccination (p.v.) (Lorenzen et al. 2002). At later time points (80 days p.v.; 880 degree days), the level of cross-protection against VHS by IHN vaccination is either completely lost (60 days p.v.; 660 degree days) (3 g rainbow trout; 1 µg vaccine dose) (Lorenzen et al. 2002) or present at intermediate levels (6.5 g rainbow trout; 1 µg vaccine dose) (Einer-Jensen et al. 2009). Comparatively, VHS vaccination remains effective as long as 9 months (2520 degree days) p.v. (100 g rainbow trout; 0.5 µg vaccine dose) (McLauchlan et al. 2003). These results suggest that IHN and VHS vaccination activate a rapid transitory innate immune response against VHSV that is followed by long-term adaptive immunity in VHS-vaccinated trout (Lorenzen et al. 2002).

  18. Experimental transmission of VHSV genotype IVb by predation.

    PubMed

    Getchell, Rodman G; Cornwell, Emily R; Groocock, Geoffrey H; Wong, Po Ting; Coffee, Laura L; Wooster, Gregory A; Bowser, Paul R

    2013-12-01

    Preliminary surveillance of wild baitfish during the 2006 viral hemorrhagic septicemia virus genotype IVb (VHSV IVb) outbreaks indicated Emerald Shiners Notropis atherinoides and Bluntnose Minnow Pimephales notatus were infected with high levels of VHSV without showing clinical signs of disease. The movement and use of baitfish was recognized as the most probable vector for the introduction of VHSV to inland waters, such as Conesus Lake and Skaneateles Lake in New York, Budd Lake in Michigan, and Little Lake Butte des Morts and Lake Winnebago in Wisconsin. While numerous government agencies implemented restrictions to stop the movement of potentially infected baitfish into new waters and prevent the spread of VHSV IVb, until now, studies to investigate whether these initial introductions were by an oral route of infection have not occurred. Our studies identified infected Fathead Minnow Pimephales promelas as suitable vectors for transmitting VHSV IVb when fed to Tiger Muskellunge ( ♂ Northern Pike Esox lucius × ♀ Muskellunge Esox masquinongy) during laboratory trials. Six of 16 Tiger Muskellunge were infected with VHSV IVb after consumption of infected Fathead Minnows when assayed with quantitative reverse transcriptase polymerase chain reaction and viral isolation in cell culture. Weekly sampling of water and feces from these Tiger Muskellunge individually reared showed intermittent shedding of VHSV IVb. Those exposed to similarly VHSV IVb-inoculated fathead minnows by cohabitation only became infected in 1 case out of 16. A similar trial of 12 Tiger Muskellunge fed Round Goby Neogobius melanostomus that survived a VHSV IVb immersion challenge did not result in infection. Overall, our findings imply that consumption of infected wild baitfish may be a risk factor for introduction of VHSV. PMID:23998650

  19. Model for ranking freshwater fish farms according to their risk of infection and illustration for viral haemorrhagic septicaemia.

    PubMed

    Oidtmann, Birgit C; Pearce, Fiona M; Thrush, Mark A; Peeler, Edmund J; Ceolin, Chiara; Stärk, Katharina D C; Dalla Pozza, Manuela; Afonso, Ana; Diserens, Nicolas; Reese, R Allan; Cameron, Angus

    2014-08-01

    We developed a model to calculate a quantitative risk score for individual aquaculture sites. The score indicates the risk of the site being infected with a specific fish pathogen (viral haemorrhagic septicaemia virus (VHSV); infectious haematopoietic necrosis virus, Koi herpes virus), and is intended to be used for risk ranking sites to support surveillance for demonstration of zone or member state freedom from these pathogens. The inputs to the model include a range of quantitative and qualitative estimates of risk factors organised into five risk themes (1) Live fish and egg movements; (2) Exposure via water; (3) On-site processing; (4) Short-distance mechanical transmission; (5) Distance-independent mechanical transmission. The calculated risk score for an individual aquaculture site is a value between zero and one and is intended to indicate the risk of a site relative to the risk of other sites (thereby allowing ranking). The model was applied to evaluate 76 rainbow trout farms in 3 countries (42 from England, 32 from Italy and 2 from Switzerland) with the aim to establish their risk of being infected with VHSV. Risk scores for farms in England and Italy showed great variation, clearly enabling ranking. Scores ranged from 0.002 to 0.254 (mean score 0.080) in England and 0.011 to 0.778 (mean of 0.130) for Italy, reflecting the diversity of infection status of farms in these countries. Requirements for broader application of the model are discussed. Cost efficient farm data collection is important to realise the benefits from a risk-based approach.

  20. Serotyping of foot and mouth disease virus and Pasteurella multocida from Indian gaurs (Bos gaurus), concurrently infected with foot and mouth disease and haemorrhagic septicaemia.

    PubMed

    Chandranaik, Basavegowdanadoddi Marinaik; Hegde, Raveendra; Shivashankar, Beechagondahalli Papanna; Giridhar, Papanna; Muniyellappa, Handenahally Kaverappa; Kalge, Rajeshwar; Sumathi, Benamanahalli Raju; Nithinprabhu, Kumble; Chandrashekara, Narasimhaiah; Manjunatha, Venkataramanappa; Jaisingh, Nirupama; Mayanna, Asha; Chandrakala, Gowda Kallenahalli; Kanaka, Sermaraja; Venkatesha, Mudalagiri Dasappagupta

    2015-06-01

    We report the serotyping of foot-and-mouth disease virus (FMDV) and Pasteurella multocida from Indian gaurs which were concurrently infected with foot-and-mouth disease (FMD) and haemorrhagic septicaemia. Bannerghatta biological park (BBP), a national park located in the outskirts of Bengaluru city, Karnataka, India, is bordered by several villages. These villages witnessed massive outbreaks of FMD which spread rapidly to the herbivores at BBP. Post-mortem was conducted on carcasses of two Indian gaurs that died with symptoms of FMD. The salient gross findings included extensive vesicular lesions on the tongue, gums, cheeks, upper palate and hooves. Haemorrhagic tracheitis and ecchymotic haemorrhages on the heart were characteristic. The vesicular lesions of oral cavity were positive for 'O' type of FMD virus by sandwich enzyme-linked immuno sorbent assay (ELISA). The heart blood and spleen samples yielded growth of pure cultures of P. multocida. The isolates were typed as P. multocida type B using KTSP61 and KTT72 primers yielding specific amplicons of 620 bp. The phylogenetic analysis of the isolates was carried by sequencing of 1.4-Kbp nucleotides on the 16S ribosomal RNA (rRNA) gene of the isolates. PMID:25894817

  1. Serotyping of foot and mouth disease virus and Pasteurella multocida from Indian gaurs (Bos gaurus), concurrently infected with foot and mouth disease and haemorrhagic septicaemia.

    PubMed

    Chandranaik, Basavegowdanadoddi Marinaik; Hegde, Raveendra; Shivashankar, Beechagondahalli Papanna; Giridhar, Papanna; Muniyellappa, Handenahally Kaverappa; Kalge, Rajeshwar; Sumathi, Benamanahalli Raju; Nithinprabhu, Kumble; Chandrashekara, Narasimhaiah; Manjunatha, Venkataramanappa; Jaisingh, Nirupama; Mayanna, Asha; Chandrakala, Gowda Kallenahalli; Kanaka, Sermaraja; Venkatesha, Mudalagiri Dasappagupta

    2015-06-01

    We report the serotyping of foot-and-mouth disease virus (FMDV) and Pasteurella multocida from Indian gaurs which were concurrently infected with foot-and-mouth disease (FMD) and haemorrhagic septicaemia. Bannerghatta biological park (BBP), a national park located in the outskirts of Bengaluru city, Karnataka, India, is bordered by several villages. These villages witnessed massive outbreaks of FMD which spread rapidly to the herbivores at BBP. Post-mortem was conducted on carcasses of two Indian gaurs that died with symptoms of FMD. The salient gross findings included extensive vesicular lesions on the tongue, gums, cheeks, upper palate and hooves. Haemorrhagic tracheitis and ecchymotic haemorrhages on the heart were characteristic. The vesicular lesions of oral cavity were positive for 'O' type of FMD virus by sandwich enzyme-linked immuno sorbent assay (ELISA). The heart blood and spleen samples yielded growth of pure cultures of P. multocida. The isolates were typed as P. multocida type B using KTSP61 and KTT72 primers yielding specific amplicons of 620 bp. The phylogenetic analysis of the isolates was carried by sequencing of 1.4-Kbp nucleotides on the 16S ribosomal RNA (rRNA) gene of the isolates.

  2. Role of the IFN I system against the VHSV infection in juvenile Senegalese sole (Solea senegalensis).

    PubMed

    Alvarez-Torres, Daniel; Podadera, Ana M; Bejar, Julia; Bandin, Isabel; Alonso, M Carmen; Garcia-Rosado, Esther

    2016-01-01

    Senegalese sole is susceptible to marine VHSV isolates but is not affected by freshwater isolates, which may indicate differences regarding virus-host immune system interaction. IFN I induces an antiviral state in fish, stimulating the expression of genes encoding antiviral proteins (ISG). In this study, the stimulation of the Senegalese sole IFN I by VHSV infections has been evaluated by the relative quantification of the transcription of several ISG (Mx, Isg15 and Pkr) after inoculation with marine (pathogenic) and freshwater (non-pathogenic) VHSV isolates. Compared to marine VHSV, lower levels of RNA of the freshwater VHSV induced transcription of ISG to similar levels, with the Isg15 showing the highest fold induction. The protective role of the IFN I system was evaluated in poly I:C-inoculated animals subsequently challenged with VHSV isolates. The cumulative mortality caused by the marine isolate in the control group was 68%, whereas in the poly I:C-stimulated group was 5%. The freshwater VHSV isolate did not cause any mortality. Furthermore, viral RNA fold change and viral titers were lower in animals from the poly I:C + VHSV groups than in the controls. The implication of the IFN I system in the protection observed was confirmed by the transcription of the ISG in animals from the poly I:C + VHSV groups. However, the marine VHSV isolate exerts a negative effect on the ISG transcription at 3 and 6 h post-inoculation (hpi), which is not observed for the freshwater isolate. This difference might be partly responsible for the virulence shown by the marine isolate. PMID:26743229

  3. Replication and persistence of VHSV IVb in freshwater turtles.

    PubMed

    Goodwin, Andrew E; Merry, Gwenn E

    2011-05-01

    With the emergence of viral hemorrhagic septicemia virus (VHSV) strain IVb in the Great Lakes of North America, hatchery managers have become concerned that this important pathogen could be transmitted by animals other than fish. Turtles are likely candidates because they are poikilotherms that feed on dead fish, but there are very few reports of rhabdovirus infections in reptiles and no reports of the fish rhabdoviruses in animals other than teleosts. We injected common snapping turtles Chelydra serpentine and red-eared sliders Trachemys scripta elegans intraperitoneally with 10(4) median tissue culture infectious dose (TCID50) of VHSV-IVb and 21 d later were able to detect the virus by quantitative real-time reverse transcriptase PCR (qrt-RTPCR) in pools of kidney, liver, and spleen. In a second experiment, snapping turtles, red-eared sliders, yellow-bellied sliders T. scripta scripta, and northern map turtles Grapetemys geographica at 14 degrees C were allowed to feed on tissues from bluegill dying of VHSV IVb disease. Turtle kidney, spleen, and brain pools were not positive by qrt-RTPCR on Day 3 post feeding, but were positive on Days 10 and 20. Map turtles on Day 20 post-feeding were positive by both qrt-RTPCR and by cell culture. Our work shows that turtles that consume infected fish are a possible vector for VHSV IVb, and that the fish rhabdoviruses may have a broader host range than previously suspected. PMID:21790064

  4. Identification of quantitative trait loci associated with resistance to viral haemorrhagic septicaemia (VHS) in turbot (Scophthalmus maximus ): a comparison between bacterium, parasite and virus diseases.

    PubMed

    Rodríguez-Ramilo, Silvia T; De La Herrán, Roberto; Ruiz-Rejón, Carmelo; Hermida, Miguel; Fernández, Carlos; Pereiro, Patricia; Figueras, Antonio; Bouza, Carmen; Toro, Miguel A; Martínez, Paulino; Fernández, Jesús

    2014-06-01

    One of the main objectives of genetic breeding programs in turbot industry is to reduce disease-related mortality. In the present study, a genome scan to detect quantitative trait loci (QTL) affecting resistance and survival to viral haemorrhagic septicaemia (VHS) was carried out. Three full-sib families with approximately 90 individuals each were genotyped and evaluated by linear regression and maximum likelihood approaches. In addition, a comparison between QTL detected for resistance and survival time to other important bacterial and parasite diseases affecting turbot (furunculosis and scuticociliatosis) was also carried out. Finally, the relationship between QTL affecting resistance/survival time to the virus and growth-related QTL was also evaluated. Several genomic regions controlling resistance and survival time to VHS were detected. Also significant associations between the evaluated traits and genotypes at particular markers were identified, explaining up to 14 % of the phenotypic variance. Several genomic regions controlling general and specific resistance to different diseases in turbot were detected. A preliminary gene mining approach identified candidate genes related to general or specific immunity. This information will be valuable to develop marker-assisted selection programs and to discover candidate genes related to disease resistance to improve turbot production.

  5. Sequence variation of the glycoprotein gene identifies three distinct lineages within field isolates of viral hemorrhagic septicemia virus, a fish rhabdovirus

    USGS Publications Warehouse

    Benmansour, A.; Bascuro, B.; Monnier, A.F.; Vende, P.; Winton, J.R.; de Kinkelin, P.

    1997-01-01

    To evaluate the genetic diversity of viral haemorrhagic septicaemia virus (VHSV), the sequence of the glycoprotein genes (G) of 11 North American and European isolates were determined. Comparison with the G protein of representative members of the family Rhabdoviridae suggested that VHSV was a different virus species from infectious haemorrhagic necrosis virus (IHNV) and Hirame rhabdovirus (HIRRV). At a higher taxonomic level, VHSV, IHNV and HIRRV formed a group which was genetically closest to the genus Lyssavirus. Compared with each other, the G genes of VHSV displayed a dissimilar overall genetic diversity which correlated with differences in geographical origin. The multiple sequence alignment of the complete G protein, showed that the divergent positions were not uniformly distributed along the sequence. A central region (amino acid position 245-300) accumulated substitutions and appeared to be highly variable. The genetic heterogeneity within a single isolate was high, with an apparent internal mutation frequency of 1.2 x 10(-3) per nucleotide site, attesting the quasispecies nature of the viral population. The phylogeny separated VHSV strains according to the major geographical area of isolation: genotype I for continental Europe, genotype II for the British Isles, and genotype III for North America. Isolates from continental Europe exhibited the highest genetic variability, with sub-groups correlated partially with the serological classification. Neither neutralizing polyclonal sera, nor monoclonal antibodies, were able to discriminate between the genotypes. The overall structure of the phylogenetic tree suggests that VHSV genetic diversity and evolution fit within the model of random change and positive selection operating on quasispecies.

  6. Salmonid fish viruses and cell interactions at early steps of the infective cycle.

    PubMed

    de las Heras, A I; Rodríguez Saint-Jean, S; Pérez-Prieto, S I

    2008-07-01

    A flow cytometric virus-binding assay that directly visualizes the binding and entry of infectious pancreatic necrosis virus (IPNV), infectious haematopoietic necrosis virus (IHNV) and virus haemorrhagic septicaemia virus (VHSV) to several cell lines was established. The highest efficiency of binding was shown by the BF-2 cell line and this was used to study, at the attachment level, the interactions of these cells with salmonid fish viruses in coinfections, and to further determine if the earliest stage of the viral growth cycle could explain the previously described loss of infectivity of IHNV when IPNV is present. Our results demonstrated that IPNV binds to around 88% of cells either in single or dual infections, whereas IHNV attachment always decreased in the presence of any of the other viruses. VHSV binding was not affected by IPNV, but coinfection with IHNV reduced the percentage of virus-binding cells, which suggests competition for viral receptors or co-receptors. Internalization of the adsorbed IHNV was not decreased by coinfection with IPNV, so the hypothetical competence could be restricted to the binding step. Treatment of the cells with antiviral agents, such as amantadine or chloroquine, did not affect the binding of IPNV and VHSV, but reduced IHNV binding by more than 30%. Tributylamine affected viral binding of the three viruses to different degrees and inhibited IPNV or IHNV entry in a large percentage of cells treated for 30 min. Tributylamine also inhibited IHNV cytopathic effects in a dose-dependent manner, decreasing the virus yield by 4 log of the 50% endpoint titre, at 10 mm concentration. IPNV was also inhibited, but at a lower level. The results of this study support the hypothesis that IHNV, in contrast to VHSV or IPNV, is less efficient at completing its growth cycle in cells with a simultaneous infection with IPNV. It can be affected at several stages of viral infection and is more sensitive to the action of antiviral compounds. PMID

  7. Can VHS Virus Bypass the Protective Immunity Induced by DNA Vaccination in Rainbow Trout?

    PubMed Central

    Sepúlveda, Dagoberto; Lorenzen, Niels

    2016-01-01

    DNA vaccines encoding viral glycoproteins have been very successful for induction of protective immunity against diseases caused by rhabdoviruses in cultured fish species. However, the vaccine concept is based on a single viral gene and since RNA viruses are known to possess high variability and adaptation capacity, this work aimed at evaluating whether viral haemorrhagic septicaemia virus (VHSV), an RNA virus and member of Rhabdoviridae family, was able to evade the protective immune response induced by the DNA vaccination of rainbow trout. The experiments comprised repeated passages of a highly pathogenic VHSV isolate in a fish cell line in the presence of neutralizing fish serum (in vitro approach), and in rainbow trout immunized with the VHS DNA vaccine (in vivo approach). For the in vitro approach, the virus collected from the last passage (passaged virus) was as sensitive as the parental virus to serum neutralization, suggesting that the passaging did not promote the selection of virus populations able to bypass the neutralization by serum antibodies. Also, in the in vivo approach, where virus was passaged several times in vaccinated fish, no increased virulence nor increased persistence in vaccinated fish was observed in comparison with the parental virus. However, some of the vaccinated fish did get infected and could transmit the infection to naïve cohabitant fish. The results demonstrated that the DNA vaccine induced a robust protection, but also that the immunity was non-sterile. It is consequently important not to consider vaccinated fish as virus free in veterinary terms. PMID:27054895

  8. Can VHS Virus Bypass the Protective Immunity Induced by DNA Vaccination in Rainbow Trout?

    PubMed

    Sepúlveda, Dagoberto; Lorenzen, Niels

    2016-01-01

    DNA vaccines encoding viral glycoproteins have been very successful for induction of protective immunity against diseases caused by rhabdoviruses in cultured fish species. However, the vaccine concept is based on a single viral gene and since RNA viruses are known to possess high variability and adaptation capacity, this work aimed at evaluating whether viral haemorrhagic septicaemia virus (VHSV), an RNA virus and member of Rhabdoviridae family, was able to evade the protective immune response induced by the DNA vaccination of rainbow trout. The experiments comprised repeated passages of a highly pathogenic VHSV isolate in a fish cell line in the presence of neutralizing fish serum (in vitro approach), and in rainbow trout immunized with the VHS DNA vaccine (in vivo approach). For the in vitro approach, the virus collected from the last passage (passaged virus) was as sensitive as the parental virus to serum neutralization, suggesting that the passaging did not promote the selection of virus populations able to bypass the neutralization by serum antibodies. Also, in the in vivo approach, where virus was passaged several times in vaccinated fish, no increased virulence nor increased persistence in vaccinated fish was observed in comparison with the parental virus. However, some of the vaccinated fish did get infected and could transmit the infection to naïve cohabitant fish. The results demonstrated that the DNA vaccine induced a robust protection, but also that the immunity was non-sterile. It is consequently important not to consider vaccinated fish as virus free in veterinary terms.

  9. Vaccine Adjuvants in Fish Vaccines Make a Difference: Comparing Three Adjuvants (Montanide ISA763A Oil, CpG/Poly I:C Combo and VHSV Glycoprotein) Alone or in Combination Formulated with an Inactivated Whole Salmonid Alphavirus Antigen.

    PubMed

    Thim, Hanna L; Villoing, Stéphane; McLoughlin, Marian; Christie, Karen Elina; Grove, Søren; Frost, Petter; Jørgensen, Jorunn B

    2014-03-25

    Most commercial vaccines offered to the aquaculture industry include inactivated antigens (Ag) formulated in oil adjuvants. Safety concerns are related to the use of oil adjuvants in multivalent vaccines for fish, since adverse side effects (e.g., adhesions) can appear. Therefore, there is a request for vaccine formulations for which protection will be maintained or improved, while the risk of side effects is reduced. Here, by using an inactivated salmonid alphavirus (SAV) as the test Ag, the combined use of two Toll-like receptor (TLR) ligand adjuvants, CpG oligonucleotides (ODNs) and poly I:C, as well as a genetic adjuvant consisting of a DNA plasmid vector expressing the viral haemorrhagic septicaemia virus (VHSV) glycoprotein (G) was explored. VHSV-G DNA vaccine was intramuscularly injected in combination with intraperitoneal injection of either SAV Ag alone or combined with the oil adjuvant, Montanide ISA763, or the CpG/polyI:C combo. Adjuvant formulations were evaluated for their ability to boost immune responses and induce protection against SAV in Atlantic salmon, following cohabitation challenge. It was observed that CpG/polyI:C-based formulations generated the highest neutralizing antibody titres (nAbs) before challenge, which endured post challenge. nAb responses for VHSV G-DNA- and oil-adjuvanted formulations were marginal compared to the CpG/poly I:C treatment. Interestingly, heat-inactivated sera showed reduced nAb titres compared to their non-heated counterparts, which suggests a role of complement-mediated neutralization against SAV. Consistently elevated levels of innate antiviral immune genes in the CpG/polyI:C injected groups suggested a role of IFN-mediated responses. Co-delivery of the VHSV-G DNA construct with either CpG/polyI:C or oil-adjuvanted SAV vaccine generated higher CD4 responses in head kidney at 48 h compared to injection of this vector or SAV Ag alone. The results demonstrate that a combination of pattern recognizing receptor (PRR

  10. Low prevalence of VHSV detected in round goby collected in offshore regions of Lake Ontario

    USGS Publications Warehouse

    Cornwell, Emily R.; Getchell, Rodman G.; Groocock, Geoffrey H.; Walsh, Maureen G.; Bowser, Paul R.

    2012-01-01

    Since the first reports of mortalities due to viral hemorrhagic septicemia virus (VHSV) type IVb in the Laurentian Great Lakes basin during 2005 (Lake St. Clair, USA and Bay of Quinte, Lake Ontario, Canada), many groups have conducted surveillance efforts for the virus, primarily in nearshore areas. The round goby (Neogobius melanostomus) has been identified as a key species to target for surveillance, because they have a very high probability of infection at a given site. Our objective in this study was to document and quantify VHSV in round gobies in offshore waters of Lake Ontario using molecular techniques. We collected 139 round gobies from depths ranging from 55 to 150 m using bottom trawls during the early spring of 2011 and detected VHSV in 4 individuals (1/26 fish at 95 m, 2/12 fish at 105 m, and 1/24 fish at 135 m). These results expand the known depth range of VHSV in the Great Lakes. They also have implications on the management of the spread of VHSV within infected bodies of water related to the mixing of populations of fish that would remain distinct in their breeding habitats, but then have the opportunity to mix in their overwintering habitats, as well as to increase overlap of predator and prey species in overwintering habitats.

  11. Septicaemia due to Pasteurella pneumotropica

    PubMed Central

    Rogers, Bogumila T.; Anderson, J. C.; Palmer, Cynthia A.; Henderson, W. G.

    1973-01-01

    The literature concerning Pasteurella pneumotropica infection in animals and man is briefly reviewed and a case presented in which the organism was the cause of septicaemia in a patient receiving chemotherapy for myeloid leukaemia. Bacteriological findings are recorded and compared with those of other authors. PMID:4352465

  12. Campylobacter insulaenigrae causing septicaemia and enteritis.

    PubMed

    Chua, Kyra; Gürtler, Volker; Montgomery, Janet; Fraenkel, Margaret; Mayall, Barrie C; Grayson, M Lindsay

    2007-11-01

    Campylobacter insulaenigrae is a novel species that has been recently only isolated from marine mammals. This is the first report of C. insulaenigrae causing enteritis and septicaemia in a patient with end-stage hepatic and renal disease.

  13. A reverse genetics system for the Great Lakes strain of viral hemorrhagic septicemia virus: the NV gene is required for pathogenicity

    USGS Publications Warehouse

    Ammayappan, Arun; Kurath, Gael; Thompson, Tarin M.; Vakharia, Vikram N.

    2011-01-01

    Viral hemorrhagic septicemia virus (VHSV), belonging to the genus Novirhabdovirus in the family of Rhabdoviridae, causes a highly contagious disease of fresh and saltwater fish worldwide. Recently, a novel genotype of VHSV, designated IVb, has invaded the Great Lakes in North America, causing large-scale epidemics in wild fish. An efficient reverse genetics system was developed to generate a recombinant VHSV of genotype IVb from cloned cDNA. The recombinant VHSV (rVHSV) was comparable to the parental wild-type strain both in vitro and in vivo, causing high mortality in yellow perch (Perca flavescens). A modified recombinant VHSV was generated in which the NV gene was substituted with an enhanced green fluorescent protein gene (rVHSV-ΔNV-EGFP), and another recombinant was made by inserting the EGFP gene into the full-length viral clone between the P and M genes (rVHSV-EGFP). The in vitro replication kinetics of rVHSV-EGFP was similar to rVHSV; however, the rVHSV-ΔNV-EGFP grew 2 logs lower. In yellow perch challenges, wtVHSV and rVHSV induced 82-100% cumulative per cent mortality (CPM), respectively, whereas rVHSV-EGFP produced 62% CPM and rVHSV-ΔNV-EGFP caused only 15% CPM. No reversion of mutation was detected in the recovered viruses and the recombinant viruses stably maintained the foreign gene after several passages. These results indicate that the NV gene of VHSV is not essential for viral replication in vitro and in vivo, but it plays an important role in viral replication efficiency and pathogenicity. This system will facilitate studies of VHSV replication, virulence, and production of viral vectored vaccines.

  14. Citrobacter koseri septicaemia in a holstein calf.

    PubMed

    Komine, M; Massa, A; Moon, L; Mullaney, T

    2014-11-01

    A 4-day-old male Holstein calf with dull mentation, nystagmus and blindness was humanely destroyed and subject to necropsy examination. Gross lesions included severe suppurative meningitis characterized by diffuse cloudy thickening of the meninges, bilateral hypopyon and fibrinosuppurative polyarthritis affecting the hocks. Citrobacter koseri was isolated from the meninges, ocular fluid, synovial fluid, spleen and small intestine. Microscopically, there was neutrophilic and histiocytic meningitis with intralesional bacilli, endophthalmitis, neutrophilic splenitis and multiple renal microabscesses. Failure of passive transfer of colostrum was confirmed. This appears to be the first characterization of septicaemia in a calf caused by C. koseri, with lesions comparable with those described in human neonates.

  15. Development of an aquatic pathogen database (AquaPathogen X) and its utilization in tracking emerging fish virus pathogens in North America.

    PubMed

    Emmenegger, E J; Kentop, E; Thompson, T M; Pittam, S; Ryan, A; Keon, D; Carlino, J A; Ranson, J; Life, R B; Troyer, R M; Garver, K A; Kurath, G

    2011-08-01

    The AquaPathogen X database is a template for recording information on individual isolates of aquatic pathogens and is freely available for download (http://wfrc.usgs.gov). This database can accommodate the nucleotide sequence data generated in molecular epidemiological studies along with the myriad of abiotic and biotic traits associated with isolates of various pathogens (e.g. viruses, parasites and bacteria) from multiple aquatic animal host species (e.g. fish, shellfish and shrimp). The cataloguing of isolates from different aquatic pathogens simultaneously is a unique feature to the AquaPathogen X database, which can be used in surveillance of emerging aquatic animal diseases and elucidation of key risk factors associated with pathogen incursions into new water systems. An application of the template database that stores the epidemiological profiles of fish virus isolates, called Fish ViroTrak, was also developed. Exported records for two aquatic rhabdovirus species emerging in North America were used in the implementation of two separate web-accessible databases: the Molecular Epidemiology of Aquatic Pathogens infectious haematopoietic necrosis virus (MEAP-IHNV) database (http://gis.nacse.org/ihnv/) released in 2006 and the MEAP- viral haemorrhagic septicaemia virus (http://gis.nacse.org/vhsv/) database released in 2010.

  16. Development of an aquatic pathogen database (AquaPathogen X) and its utilization in tracking emerging fish virus pathogens in North America

    USGS Publications Warehouse

    Emmenegger, E.J.; Kentop, E.; Thompson, T.M.; Pittam, S.; Ryan, A.; Keon, D.; Carlino, J.A.; Ranson, J.; Life, R.B.; Troyer, R.M.; Garver, K.A.; Kurath, G.

    2011-01-01

    The AquaPathogen X database is a template for recording information on individual isolates of aquatic pathogens and is freely available for download (http://wfrc.usgs.gov). This database can accommodate the nucleotide sequence data generated in molecular epidemiological studies along with the myriad of abiotic and biotic traits associated with isolates of various pathogens (e.g. viruses, parasites and bacteria) from multiple aquatic animal host species (e.g. fish, shellfish and shrimp). The cataloguing of isolates from different aquatic pathogens simultaneously is a unique feature to the AquaPathogen X database, which can be used in surveillance of emerging aquatic animal diseases and elucidation of key risk factors associated with pathogen incursions into new water systems. An application of the template database that stores the epidemiological profiles of fish virus isolates, called Fish ViroTrak, was also developed. Exported records for two aquatic rhabdovirus species emerging in North America were used in the implementation of two separate web-accessible databases: the Molecular Epidemiology of Aquatic Pathogens infectious haematopoietic necrosis virus (MEAP-IHNV) database (http://gis.nacse.org/ihnv/) released in 2006 and the MEAP- viral haemorrhagic septicaemia virus (http://gis.nacse.org/vhsv/) database released in 2010.

  17. Development and evaluation of a blocking enzyme-linked immunosorbent assay and virus neutralization assay to detect antibodies to viral hemorrhagic septicemia virus

    USGS Publications Warehouse

    Wilson, Anna; Goldberg, Tony; Marcquenski, Susan; Olson, Wendy; Goetz, Frederick; Hershberger, Paul; Hart, Lucas M.; Toohey-Kurth, Kathy

    2014-01-01

    Viral hemorrhagic septicemia virus (VHSV) is a target of surveillance by many state and federal agencies in the United States. Currently, the detection of VHSV relies on virus isolation, which is lethal to fish and indicates only the current infection status. A serological method is required to ascertain prior exposure. Here, we report two serologic tests for VHSV that are nonlethal, rapid, and species independent, a virus neutralization (VN) assay and a blocking enzyme-linked immunosorbent assay (ELISA). The results show that the VN assay had a specificity of 100% and sensitivity of 42.9%; the anti-nucleocapsid-blocking ELISA detected nonneutralizing VHSV antibodies at a specificity of 88.2% and a sensitivity of 96.4%. The VN assay and ELISA are valuable tools for assessing exposure to VHSV.

  18. Development and Evaluation of a Blocking Enzyme-Linked Immunosorbent Assay and Virus Neutralization Assay To Detect Antibodies to Viral Hemorrhagic Septicemia Virus

    PubMed Central

    Wilson, Anna; Goldberg, Tony; Marcquenski, Susan; Olson, Wendy; Goetz, Frederick; Hershberger, Paul; Hart, Lucas

    2014-01-01

    Viral hemorrhagic septicemia virus (VHSV) is a target of surveillance by many state and federal agencies in the United States. Currently, the detection of VHSV relies on virus isolation, which is lethal to fish and indicates only the current infection status. A serological method is required to ascertain prior exposure. Here, we report two serologic tests for VHSV that are nonlethal, rapid, and species independent, a virus neutralization (VN) assay and a blocking enzyme-linked immunosorbent assay (ELISA). The results show that the VN assay had a specificity of 100% and sensitivity of 42.9%; the anti-nucleocapsid-blocking ELISA detected nonneutralizing VHSV antibodies at a specificity of 88.2% and a sensitivity of 96.4%. The VN assay and ELISA are valuable tools for assessing exposure to VHSV. PMID:24429071

  19. Detection of viral hemorrhagic septicemia virus

    USGS Publications Warehouse

    Winton, James; Kurath, Gael; Batts, William

    2007-01-01

    Viral hemorrhagic septicemia virus (VHSV) is considered to be one of the most important viral pathogens of finfish and is listed as reportable by many nations and international organizations (Office International des Epizooties 2006). Prior to 1988, VHSV was thought to be limited to Europe (Wolf 1988; Smail 1999). Subsequently, it was shown that the virus is endemic among many marine and anadromous fish species in both the Pacific and Atlantic Oceans (Meyers and Winton 1995; Skall et al. 2005). Genetic analysis reveals that isolates of VHSV can be divided into four genotypes that generally correlate with geographic location with the North American isolates generally falling into VHSV Genotype IV (Snow et al. 2004). In 2005-2006, reports from the Great Lakes region indicated that wild fish had experienced disease or, in some cases, very large die-offs from VHSV (Elsayed et al. 2006, Lumsden et al. 2007). The new strain from the Great Lakes, now identified as VHSV Genotype IVb, appears most closely related to isolates of VHSV from mortalities that occurred during 2000-2004 in rivers and near-shore areas of New Brunswick and Nova Scotia, Canada (Gagne et al. 2007). The type IVb isolate found in the Great Lakes region is the only strain outside of Europe that has been associated with significant mortality in freshwater species.

  20. Screening for Viral Hemorrhagic Septicemia Virus in Marine Fish along the Norwegian Coastal Line

    PubMed Central

    Sandlund, Nina; Gjerset, Britt; Bergh, Øivind; Modahl, Ingebjørg; Olesen, Niels Jørgen; Johansen, Renate

    2014-01-01

    Viral hemorrhagic septicemia virus (VHSV) infects a wide range of marine fish species. To study the occurrence of VHSV in wild marine fish populations in Norwegian coastal waters and fjord systems a total of 1927 fish from 39 different species were sampled through 5 research cruises conducted in 2009 to 2011. In total, VHSV was detected by rRT-PCR in twelve samples originating from Atlantic herring (Clupea harengus), haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangus) and silvery pout (Gadiculus argenteus). All fish tested positive in gills while four herring and one silvery pout also tested positive in internal organs. Successful virus isolation in cell culture was only obtained from one pooled Atlantic herring sample which shows that today's PCR methodology have a much higher sensitivity than cell culture for detection of VHSV. Sequencing revealed that the positive samples belonged to VHSV genotype Ib and phylogenetic analysis shows that the isolate from Atlantic herring and silvery pout are closely related. All positive fish were sampled in the same area in the northern county of Finnmark. This is the first detection of VHSV in Atlantic herring this far north, and to our knowledge the first detection of VHSV in silvery pout. However, low prevalence of VHSV genotype Ib in Atlantic herring and other wild marine fish are well known in other parts of Europe. Earlier there have been a few reports of disease outbreaks in farmed rainbow trout with VHSV of genotype Ib, and our results show that there is a possibility of transfer of VHSV from wild to farmed fish along the Norwegian coast line. The impact of VHSV on wild fish is not well documented. PMID:25248078

  1. Differences in Virulence of Marine and Freshwater Isolates of Viral Hemorrhagic Septicemia Virus In Vivo Correlate with In Vitro Ability To Infect Gill Epithelial Cells and Macrophages of Rainbow Trout (Oncorhynchus mykiss)▿

    PubMed Central

    Brudeseth, Bjørn E.; Skall, Helle F.; Evensen, Øystein

    2008-01-01

    Two strains of viral hemorrhagic septicemia virus (VHSV) with known different virulence characteristics in vivo were studied (by a time course approach) for their abilities to infect and translocate across a primary culture of gill epithelial cells (GEC) of rainbow trout (RBT; Oncorhynchus mykiss). The strains included one low-virulence marine VHSV (ma-VHSV) strain, ma-1p8, and a highly pathogenic freshwater VHSV (fw-VHSV) strain, fw-DK-3592B. Infectivities toward trout head kidney macrophages were also studied (by a time course method), and differences in in vivo virulence were reconfirmed, the aim being to determine any correlation between in vivo virulence and in vitro infectivity. The in vitro studies showed that the fw-VHSV isolate infected and caused a cytotoxic effect in monolayers of GEC (demonstrating virulence) at an early time point (2 h postinoculation) and that the same virus strain had translocated over a confluent, polarized GEC layer by 2 h postinoculation. The marine isolate did not infect monolayers of GEC, and delayed translocation across polarized GEC was seen by 48 h postinoculation. Primary cultures of head kidney macrophages were also infected with fw-VHSV, with a maximum of 9.5% virus-positive cells by 3 days postinfection, while for the ma-VHSV strain, only 0.5% of the macrophages were positive after 3 days of culture. In vivo studies showed that the fw-VHSV strain was highly virulent for RBT fry and caused high mortality, with classical features of viral hemorrhagic septicemia. The ma-VHSV showed a very low level of virulence (only one pool of samples from the dead fish was VHSV positive). This study has shown that the differences in virulence between marine and freshwater strains of VHSV following the in vivo infection of RBT correlate with in vitro abilities to infect primary cultures of GEC and head kidney macrophages of the same species. PMID:18753199

  2. Genetic diversification of an emerging pathogen: A decade of mutation by the fish Viral Hemorrhagic Septicemia (VHS) virus in the Laurentian Great Lakes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Viral Hemorrhagic Septicemia virus (VHSv) is an RNA rhabdovirus, which causes one of the world's most serious fish diseases, infecting >80 freshwater and marine species across the Northern Hemisphere. A new, novel, and especially virulent substrain - VHSv-IVb - first appeared in the Laurentian Gre...

  3. Distribution of an invasive aquatic pathogen (viral hemorrhagic septicemia virus) in the Great Lakes and its relationship to shipping

    USGS Publications Warehouse

    Bain, Mark B.; Cornwell, Emily R.; Hope, Kristine M.; Eckerlin, Geofrey E.; Casey, Rufina N.; Groocock, Geoffrey H.; Getchell, Rodman G.; Bowser, Paul R.; Winton, James R.; Batts, William N.; Cangelosi, Allegra; Casey, James W.

    2010-01-01

    Viral hemorrhagic septicemia virus (VHSV) is a rhabdovirus found in fish from oceans of the northern hemisphere and freshwaters of Europe. It has caused extensive losses of cultured and wild fish and has become established in the North American Great Lakes. Large die-offs of wild fish in the Great Lakes due to VHSV have alarmed the public and provoked government attention on the introduction and spread of aquatic animal pathogens in freshwaters. We investigated the relations between VHSV dispersion and shipping and boating activity in the Great Lakes by sampling fish and water at sites that were commercial shipping harbors, recreational boating centers, and open shorelines. Fish and water samples were individually analyzed for VHSV using quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and cell culture assays. Of 1,221 fish of 17 species, 55 were VHSV positive with highly varied qRT-PCR titers (1 to 5,950,000 N gene copies). The detections of VHSV in fish and water samples were closely associated and the virus was detected in 21 of 30 sites sampled. The occurrence of VHSV was not related to type of site or shipping related invasion hotspots. Our results indicate that VHSV is widely dispersed in the Great Lakes and is both an enzootic and epizootic pathogen. We demonstrate that pathogen distribution information could be developed quickly and is clearly needed for aquatic ecosystem conservation, management of affected populations, and informed regulation of the worldwide trade of aquatic organisms.

  4. Distribution of an Invasive Aquatic Pathogen (Viral Hemorrhagic Septicemia Virus) in the Great Lakes and Its Relationship to Shipping

    PubMed Central

    Bain, Mark B.; Cornwell, Emily R.; Hope, Kristine M.; Eckerlin, Geofrey E.; Casey, Rufina N.; Groocock, Geoffrey H.; Getchell, Rodman G.; Bowser, Paul R.; Winton, James R.; Batts, William N.; Cangelosi, Allegra; Casey, James W.

    2010-01-01

    Viral hemorrhagic septicemia virus (VHSV) is a rhabdovirus found in fish from oceans of the northern hemisphere and freshwaters of Europe. It has caused extensive losses of cultured and wild fish and has become established in the North American Great Lakes. Large die-offs of wild fish in the Great Lakes due to VHSV have alarmed the public and provoked government attention on the introduction and spread of aquatic animal pathogens in freshwaters. We investigated the relations between VHSV dispersion and shipping and boating activity in the Great Lakes by sampling fish and water at sites that were commercial shipping harbors, recreational boating centers, and open shorelines. Fish and water samples were individually analyzed for VHSV using quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and cell culture assays. Of 1,221 fish of 17 species, 55 were VHSV positive with highly varied qRT-PCR titers (1 to 5,950,000 N gene copies). The detections of VHSV in fish and water samples were closely associated and the virus was detected in 21 of 30 sites sampled. The occurrence of VHSV was not related to type of site or shipping related invasion hotspots. Our results indicate that VHSV is widely dispersed in the Great Lakes and is both an enzootic and epizootic pathogen. We demonstrate that pathogen distribution information could be developed quickly and is clearly needed for aquatic ecosystem conservation, management of affected populations, and informed regulation of the worldwide trade of aquatic organisms. PMID:20405014

  5. In vivo and in vitro phenotypic differences between Great Lakes VHSV genotype IVb isolates with sequence types vcG001 and vcG002

    PubMed Central

    Imanse, Sierra M.; Cornwell, Emily R.; Getchell, Rodman G.; Kurath, Gael; Bowser, Paul R.

    2014-01-01

    Viral hemorrhagic septicemia virus (VHSV) is an aquatic rhabdovirus first recognized in farmed rainbow trout in Denmark. In the past decade, a new genotype of this virus, IVb was discovered in the Laurentian Great Lakes basin and has caused several massive die-offs in some of the 28 species of susceptible North American freshwater fishes. Since its colonization of the Great Lakes, several closely related sequence types within genotype IVb have been reported, the two most common of which are vcG001 and vcG002. These sequence types have different spatial distributions in the Great Lakes. The aim of this study was to determine whether the genotypic differences between representative vcG001 (isolate MI03) and vcG002 (isolate 2010-030 #91) isolates correspond to phenotypic differences in terms of virulence using both an in vitro and in vivo approach. In vitro infection of epithelioma papulosum cyprini (EPC), bluegill fry (BF-2), and Chinook salmon embryo (CHSE) cells demonstrated some differences in onset and rate of growth in EPC and BF-2 cells, without any difference in the quantity of RNA produced. In vivo infection of round gobies (Neogobius melanostomus) via immersion exposure to different concentrations of vcG001 or vcG002 caused a significantly greater mortality in round gobies exposed to 102 plaque forming units ml−1 of vcG001. These experiments suggest that there are phenotypic differences between Great Lakes isolates of VHSV genotype IVb. PMID:25722533

  6. In vivo and in vitro phenotypic differences between Great Lakes VHSV genotype IVb isolates with sequence types vcG001 and vcG002

    USGS Publications Warehouse

    Imanse, Sierra M.; Cornwell, Emily R.; Getchell, Rodman G.; Kurath, Gael; Bowser, Paul R.

    2014-01-01

    Viral hemorrhagic septicemia virus (VHSV) is an aquatic rhabdovirus first recognized in farmed rainbow trout in Denmark. In the past decade, a new genotype of this virus, IVb was discovered in the Laurentian Great Lakes basin and has caused several massive die-offs in some of the 28 species of susceptible North American freshwater fishes. Since its colonization of the Great Lakes, several closely related sequence types within genotype IVb have been reported, the two most common of which are vcG001 and vcG002. These sequence types have different spatial distributions in the Great Lakes. The aim of this study was to determine whether the genotypic differences between representative vcG001 (isolate MI03) and vcG002 (isolate 2010-030 #91) isolates correspond to phenotypic differences in terms of virulence using both in vitro and in vivo approaches. In vitro infection of epithelioma papulosum cyprini (EPC), bluegill fry (BF-2), and Chinook salmon embryo (CHSE) cells demonstrated some differences in onset and rate of growth in EPC and BF-2 cells, without any difference in the quantity of RNA produced. In vivo infection of round gobies (Neogobius melanostomus) via immersion exposure to different concentrations of vcG001 or vcG002 caused a significantly greater mortality in round gobies exposed to 102 plaque forming units ml− 1 of vcG001. These experiments suggest that there are phenotypic differences between Great Lakes isolates of VHSV genotype IVb.

  7. Limited Interference at the Early Stage of Infection between Two Recombinant Novirhabdoviruses: Viral Hemorrhagic Septicemia Virus and Infectious Hematopoietic Necrosis Virus▿ †

    PubMed Central

    Biacchesi, Stéphane; Lamoureux, Annie; Mérour, Emilie; Bernard, Julie; Brémont, Michel

    2010-01-01

    The genome sequence of a hypervirulent novirhabdovirus, viral hemorrhagic septicemia virus (VHSV) French strain 23-75, was determined. Compared to the genome of the prototype Fil3 strain, a number of substitutions, deletions, and insertions were observed. Following the establishment of a plasmid-based minigenome replication assay, recombinant VHSV (rVHSV) was successfully recovered. rVHSV exhibits wild-type-like growth properties in vitro as well as in vivo in rainbow trout. The dispensable role of NV for the novirhabdovirus replication was confirmed by generating rVHSV-ΔNV, in which the NV gene was deleted. This deletion mutant was shown to be as debilitated as that previously described for infectious hematopoietic necrosis virus (IHNV), a distantly related novirhabdovirus (S. Biacchesi, M. I. Thoulouze, M. Bearzotti, Y. X. Yu, and M. Bremont, J. Virol. 74:11247-11253, 2000). Recombinant VHSV and IHNV expressing tdTomato and GFPmax reporter genes, respectively, were generated, demonstrating the potential of these rhabdoviruses to serve as viral vectors. Interestingly, rIHNV-GFPmax could be recovered using the replicative complex proteins of either virus, whereas rVHSV-Tomato could be recovered only by using its own replicative complex, reflecting that the genome signal sequences of VHSV are relatively distant from those of IHNV and do not allow their cross-recognition. Moreover, the use of heterologous protein combinations underlined the importance of strong protein-protein interactions for the formation of a functional ribonucleoprotein complex. The rIHNV-GFPmax and rVHSV-Tomato viruses were used to simultaneously coinfect cell monolayers. It was observed that up to 74% of the cell monolayer was coinfected by both viruses, demonstrating that a limited interference phenomenon exists during the early stage of primary infection, and it was not mediated by a cellular antiviral protein or by some of the viral proteins. PMID:20631140

  8. Haemorrhagic smolt syndrome (HSS) in Norway: pathology and associated virus-like particles.

    PubMed

    Nylund, A; Plarre, H; Hodneland, K; Devold, M; Aspehaug, V; Aarseth, M; Koren, C; Watanabe, K

    2003-03-17

    Atlantic salmon Salmo salar pre-smolt, smolt and post-smolt, with clinical signs of haemorrhagic smolt syndrome (HSS) have been found in several locations along the Norwegian coast (Rogaland to Troms). Affected fish had pale gills and bleeding at the fin bases, but seemed to be in good physical condition with no obvious weight loss. The internal organs and body cavity showed distinct bleedings. Petechiae were found on the gastrointestinal tract, swim bladder and peritoneum, visceral adipose tissue, heart and somatic musculature. The liver was bright yellow and sometimes mottled with petechiae and ecchymoses. Acitic fluid was found in the visceral cavity and fluid was also present in the pericardial cavity. Histological examination revealed haemorrhage in most organs. The glomeruli were degenerated and the renal tubules were filled with erythrocytes. The aims of this study were to describe the pathology and discover, if possible, the aetiology of the HSS. Tissues were collected for light and transmission electron microscopy (TEM), immunofluorescence (IFAT), reverse transcription (RT)-PCR diagnostics (screening for infectious salmon anaemia virus [ISAV], viral haemorrhagic septicaemia virus [VHSV], salmon pancreas disease virus [SPDV], sleeping disease virus [SDV] and infectious haematopoetic necrosis virus [IHNV]), and tissue homogenates (heart, liver, kidney and spleen) were sterile-filtered and inoculated into cell cultures. Homogenates made from several tissues were also injected intraperitoneally into salmon and rainbow trout Oncorhynchus mykiss. The diagnostic tests revealed no consistent findings of any pathogens, with the exception of TEM which showed 2 types of virus-like particles: Type I was 50 to 60 nm in diameter and Type II about 50 nm in diameter. These virus-like particles were found in salmon from all farms affected by HSS and screened by TEM. Several different cells, blood vessel endothelial cells, endocardial cells, heart myofibres, and leukocytes

  9. A Recombinant Novirhabdovirus Presenting at the Surface the E Glycoprotein from West Nile Virus (WNV) Is Immunogenic and Provides Partial Protection against Lethal WNV Challenge in BALB/c Mice

    PubMed Central

    Nzonza, Angella; Lecollinet, Sylvie; Chat, Sophie; Lowenski, Steeve; Mérour, Emilie; Biacchesi, Stéphane; Brémont, Michel

    2014-01-01

    West Nile Virus (WNV) is a zoonotic mosquito-transmitted flavivirus that can infect and cause disease in mammals including humans. Our study aimed at developing a WNV vectored vaccine based on a fish Novirhabdovirus, the Viral Hemorrhagic Septicemia virus (VHSV). VHSV replicates at temperatures lower than 20°C and is naturally inactivated at higher temperatures. A reverse genetics system has recently been developed in our laboratory for VHSV allowing the addition of genes in the viral genome and the recovery of the respective recombinant viruses (rVHSV). In this study, we have generated rVHSV vectors bearing the complete WNV envelope gene (EWNV) (rVHSV-EWNV) or fragments encoding E subdomains (either domain III alone or domain III fused to domain II) (rVHSV-DIIIWNV and rVHSV-DII-DIIIWNV, respectively) in the VHSV genome between the N and P cistrons. With the objective to enhance the targeting of the EWNV protein or EWNV-derived domains to the surface of VHSV virions, Novirhadovirus G-derived signal peptide and transmembrane domain (SPG and TMG) were fused to EWNV at its amino and carboxy termini, respectively. By Western-blot analysis, electron microscopy observations or inoculation experiments in mice, we demonstrated that both the EWNV and the DIIIWNV could be expressed at the viral surface of rVHSV upon addition of SPG. Every constructs expressing EWNV fused to SPG protected 40 to 50% of BALB/cJ mice against WNV lethal challenge and specifically rVHSV-SPGEWNV induced a neutralizing antibody response that correlated with protection. Surprisingly, rVHSV expressing EWNV-derived domain III or II and III were unable to protect mice against WNV challenge, although these domains were highly incorporated in the virion and expressed at the viral surface. In this study we demonstrated that a heterologous glycoprotein and non membrane-anchored protein, can be efficiently expressed at the surface of rVHSV making this approach attractive to develop new vaccines against

  10. Spread of the emerging viral hemorrhagic septicemia virus strain, genotype IVb, in Michigan, USA.

    PubMed

    Faisal, Mohamed; Shavalier, Megan; Kim, Robert K; Millard, Elena V; Gunn, Michelle R; Winters, Andrew D; Schulz, Carolyn A; Eissa, Alaa; Thomas, Michael V; Wolgamood, Martha; Whelan, Gary E; Winton, James

    2012-05-01

    In 2003, viral hemorrhagic septicemia virus (VHSV) emerged in the Laurentian Great Lakes causing serious losses in a number of ecologically and recreationally important fish species. Within six years, despite concerted managerial preventive measures, the virus spread into the five Great Lakes and to a number of inland waterbodies. In response to this emerging threat, cooperative efforts between the Michigan Department of Natural Resources (MI DNR), the Michigan State University Aquatic Animal Health Laboratory (MSU-AAHL), and the United States Department of Agriculture-Animal and Plant Health Inspection Services (USDA-APHIS) were focused on performing a series of general and VHSV-targeted surveillances to determine the extent of virus trafficking in the State of Michigan. Herein we describe six years (2005-2010) of testing, covering hundreds of sites throughout Michigan's Upper and Lower Peninsulas. A total of 96,228 fish representing 73 species were checked for lesions suggestive of VHSV and their internal organs tested for the presence of VHSV using susceptible cell lines. Of the 1,823 cases tested, 30 cases from 19 fish species tested positive for VHSV by tissue culture and were confirmed by reverse transcriptase polymerase chain reaction (RT-PCR). Gene sequence analyses of all VHSV isolates retrieved in Michigan demonstrated that they belong to the emerging sublineage "b" of the North American VHSV genotype IV. These findings underscore the complexity of VHSV ecology in the Great Lakes basin and the critical need for rigorous legislation and regulatory guidelines in order to reduce the virus spread within and outside of the Laurentian Great Lakes watershed.

  11. Spread of the Emerging Viral Hemorrhagic Septicemia Virus Strain, Genotype IVb, in Michigan, USA

    PubMed Central

    Faisal, Mohamed; Shavalier, Megan; Kim, Robert K.; Millard, Elena V.; Gunn, Michelle R.; Winters, Andrew D.; Schulz, Carolyn A.; Eissa, Alaa; Thomas, Michael V.; Wolgamood, Martha; Whelan, Gary E.; Winton, James

    2012-01-01

    In 2003, viral hemorrhagic septicemia virus (VHSV) emerged in the Laurentian Great Lakes causing serious losses in a number of ecologically and recreationally important fish species. Within six years, despite concerted managerial preventive measures, the virus spread into the five Great Lakes and to a number of inland waterbodies. In response to this emerging threat, cooperative efforts between the Michigan Department of Natural Resources (MI DNR), the Michigan State University Aquatic Animal Health Laboratory (MSU-AAHL), and the United States Department of Agriculture-Animal and Plant Health Inspection Services (USDA-APHIS) were focused on performing a series of general and VHSV-targeted surveillances to determine the extent of virus trafficking in the State of Michigan. Herein we describe six years (2005–2010) of testing, covering hundreds of sites throughout Michigan’s Upper and Lower Peninsulas. A total of 96,228 fish representing 73 species were checked for lesions suggestive of VHSV and their internal organs tested for the presence of VHSV using susceptible cell lines. Of the 1,823 cases tested, 30 cases from 19 fish species tested positive for VHSV by tissue culture and were confirmed by reverse transcriptase polymerase chain reaction (RT-PCR). Gene sequence analyses of all VHSV isolates retrieved in Michigan demonstrated that they belong to the emerging sublineage “b” of the North American VHSV genotype IV. These findings underscore the complexity of VHSV ecology in the Great Lakes basin and the critical need for rigorous legislation and regulatory guidelines in order to reduce the virus spread within and outside of the Laurentian Great Lakes watershed. PMID:22754647

  12. Early Onset Neonatal Septicaemia Caused by Pantoea agglomerans

    PubMed Central

    Sengupta, Mallika; Das, Niloy Kumar; Guchhait, Partha; Misra, Saheli

    2016-01-01

    Pantoea agglomerans is an opportunistic pathogen causing infection in the immunocompromised patients. It is a plant pathogen and a rare human pathogen causing neonatal sepsis, joint infection, urinary tract infection and bloodstream infections. Neonatal Gram negative septicaemia may have an unusual presentation of subtle generalised neonatal seizures without any other cardinal features of sepsis. An appropriate diagnosis is therefore the key to proper management. P. agglomerans being an unusual cause of neonatal sepsis should be diagnosed early with proper antibiogram for clinical cure. Here, we report a case of neonatal sepsis caused by P. agglomerans in a tertiary care hospital in Eastern India. PMID:27437219

  13. An active DNA vaccine against infectious pancreatic necrosis virus (IPNV) with a different mode of action than fish rhabdovirus DNA vaccines.

    PubMed

    Cuesta, A; Chaves-Pozo, E; de Las Heras, A I; Saint-Jean, S Rodríguez; Pérez-Prieto, S; Tafalla, C

    2010-04-26

    Although there are some commercial vaccines available against infectious pancreatic necrosis virus (IPNV), the disease still continues to be a major problem for aquaculture development worldwide. In the current work, we constructed a DNA vaccine against IPNV (pIPNV-PP) by cloning the long open reading frame of the polyprotein encoded by the viral RNA segment A. In vitro, the vaccine is properly translated giving the functional IPNV polyprotein since preVP2, VP2 and VP3 proteins were detected because of the VP4-protease cleavage. EPC cells transfected with the vaccine plasmid expressed the viral proteins and induced the expression of type I interferon (IFN)-induced Mx genes. Furthermore, IPNV synthesized proteins seemed to assemble in virus-like particles as evidenced by electron microscopy. In vivo, rainbow trout specimens were intramuscularly injected with the vaccine and expression of immune-relevant genes, the presence of neutralizing antibodies and effect on viral load was determined. The pIPNV-PP vaccine was expressed at the injection site and up-regulated MHC Ialpha, MHC IIalpha, type-I interferon (IFN), Mx, CD4 and CD8alpha gene expression in the muscle, head kidney or spleen, although to a much lower extent than the up-regulations observed in response to an effective DNA vaccine against viral hemorrhagic septicaemia virus (VHSV). However, the IPNV vaccine was also very effective in terms of acquired immunity since it elicited neutralizing antibodies (in 6 out of 8 trout fingerlings) and decreased 665-fold the viral load after IPNV infection. The effectiveness of this new IPNV DNA vaccine and its possible mechanism of action are discussed and compared to other viral vaccines.

  14. Effect of viral hemorrhagic septicemia virus on Pacific herring in Prince William Sound, Alaska, from 1989 to 2005.

    PubMed

    Elston, Ralph A; Meyers, Theodore R

    2009-02-25

    We critically review the role of viral hemorrhagic septicemia virus (VHSV) in the 1992-1993 collapse of the Prince William Sound (PWS) herring fishery. VHSV was detected in samples of moribund Pacific herring from PWS in spring 1993 when about 63% of the expected fish failed to appear. A low prevalence and severity of VHSV were observed in adult pre-spawning PWS herring in most of the years from 1994 to 2002. The North American strain of VHSV became established about 500 yr ago in many northeast Pacific marine fish species, including herring. In Alaska, the typical annual prevalence of VHSV in pre-spawning herring ranges from 0 to 17%. New threshold analysis of a 9 yr study indicates that only about half of the virus-infected adult fish in PWS were clinically affected; ulcers formerly attributed to VHS have been overestimated by a factor of about 3. We conclude that VHSV was not a primary causative factor in the PWS herring population collapse or in its failure to recover. Because older age classes of herring were not disproportionately missing in 1993, the protozoan Ichthyophonus hoferi was also not a likely cause of losses. The 'Exxon Valdez' oil spill occurred in PWS, Alaska, U.S.A., in 1989. Evidence for interaction of oil and VHSV expression is also evaluated. A study exposing herring to varying concentrations of weathered crude oil showed increasing prevalences of VHSV correlated with oil concentration; however, repeated experiments with juvenile and adult fish failed to corroborate these results or link oil to VHSV infection in herring.

  15. Effect of viral hemorrhagic septicemia virus on Pacific herring in Prince William Sound, Alaska, from 1989 to 2005.

    PubMed

    Elston, Ralph A; Meyers, Theodore R

    2009-02-25

    We critically review the role of viral hemorrhagic septicemia virus (VHSV) in the 1992-1993 collapse of the Prince William Sound (PWS) herring fishery. VHSV was detected in samples of moribund Pacific herring from PWS in spring 1993 when about 63% of the expected fish failed to appear. A low prevalence and severity of VHSV were observed in adult pre-spawning PWS herring in most of the years from 1994 to 2002. The North American strain of VHSV became established about 500 yr ago in many northeast Pacific marine fish species, including herring. In Alaska, the typical annual prevalence of VHSV in pre-spawning herring ranges from 0 to 17%. New threshold analysis of a 9 yr study indicates that only about half of the virus-infected adult fish in PWS were clinically affected; ulcers formerly attributed to VHS have been overestimated by a factor of about 3. We conclude that VHSV was not a primary causative factor in the PWS herring population collapse or in its failure to recover. Because older age classes of herring were not disproportionately missing in 1993, the protozoan Ichthyophonus hoferi was also not a likely cause of losses. The 'Exxon Valdez' oil spill occurred in PWS, Alaska, U.S.A., in 1989. Evidence for interaction of oil and VHSV expression is also evaluated. A study exposing herring to varying concentrations of weathered crude oil showed increasing prevalences of VHSV correlated with oil concentration; however, repeated experiments with juvenile and adult fish failed to corroborate these results or link oil to VHSV infection in herring. PMID:19402455

  16. The influence of septicaemia on spontaneous motility in preterm infants.

    PubMed

    Bos, A F; van Asperen, R M; de Leeuw, D M; Prechtl, H F

    1997-11-24

    The qualitative assessment of general movements (GMs) in preterm infants is a sensitive method to investigate the integrity of the central nervous system. The question arises whether systemic infections affect the quality of GMs in a similar fashion to brain lesions. We were able to provide an answer to this problem in six infants (gestational age 24.4-32.4 weeks, birth weight 600-1660 grams), who had initially normal GMs as analyzed from sequential video-recordings. All infants sustained a proven septicaemia (Candida albicans in two, Staphylococcus aureus in three, a coagulase-negative staphylococcus in one infant). Unintentionally, recordings were also made during the acute phase. The complexity and variability of the GMs remained largely intact in five of the six infants; only one infant had transiently abnormal GMs. Compared with 1 week before the acute phase, the speed and amplitude of the GMs were diminished, giving the GMs a sluggish appearance. One to two weeks after the acute phase of septicaemia, the quality of GMs, i.e. speed and amplitude, had normalized in all infants. This study demonstrates that it is possible to discriminate between abnormal GMs due to cerebral lesions and sluggish GMs due to severe systemic infections, when the complexity of the GMs is considered as the main characteristic for judgement of normality of GM-quality. PMID:9467694

  17. Comparative studies for serodiagnosis of haemorrhagic septicaemia in cattle sera.

    PubMed

    El-Jakee, Jakeen K; Ali, Samah Said; El-Shafii, Soumaya Ahmed; Hessain, Ashgan M; Al-Arfaj, Abdullah A; Mohamed, Moussa I

    2016-01-01

    Haemorrhagic septicaemia caused by Pasteurella multocida is a major epizootic disease in cattle and buffaloes in developing countries with high morbidity and mortality rate. In the present study, a total of 88 P. multocida isolates were isolated from 256 nasopharyngeal swabs and lung tissues samples (34.4%) during the period from January, 2013 to March, 2014 from different governorates located in Egypt. Dead calves showed the highest percentage of P. multocida isolation followed by the emergency slaughtered calves, diseased calves then apparently healthy ones. These isolates were confirmed as P. multocida microscopically, biochemically by traditional tests and by API 20E commercial kit then by PCR. The percentages of positive serum samples using somatic antigen and micro-agglutination test at 1/1280 diluted serum were 10%, 54.49% and 0% in apparently healthy, diseased and emergency slaughtered samples, respectively whereas, the percentages using capsular antigen and indirect haemagglutination test were 40%, 60.89% and 60% in apparently healthy, diseased and emergency slaughtered samples, respectively. The ELISA showed the highest sensitivity for diagnosing P. multocida in apparently healthy, diseased and emergency slaughtered animals with percentages of 42%; 92.9% and 80%, respectively. The obtained results revealed that the ELISA using capsular antigen of P. multocida is a more sensitive and specific serological test for diagnosis of haemorrhagic septicaemia. PMID:26858538

  18. Establishment and partial characterization of a cell line from burbot Lota lota maculosa: susceptibility to IHNV, IPNV and VHSV.

    USGS Publications Warehouse

    Batts, William N.; Polinski, Mark P.; Drennan, John D.; Ireland, Susan C.; Cain, Kenneth D.

    2010-01-01

    This study describes the development and partial characterization of a continuous fibroblastic-like cell line (BEF-1) developed from late stage embryos of North American burbot Lota lota maculosa. This cell line has been maintained for over 5 yr and 100 passages in vitro. Cells were cultured using Eagle’s minimum essential medium with Earle’s salts (MEM) supplemented with GlutaMAX™, and 10% fetal bovine serum (FBS), pH 7.4. The addition of penicillin-streptomycin-neomycin (PSN) antibiotic mixture (0.05, 0.05, 0.1 mg ml–1, respectively) did not negatively influence cell replication; however, the antimycotic Fungizone™ (2.5 µg ml–1, amphotericin B) caused cell rounding and resulted in a severe decrease in cell proliferation. Optimal incubation temperature has been observed between 15 and 23°C, and at these temperatures cultures are routinely passed using standard trypsinization methods every 5 to 7 d at a split ratio of 1:3 or 1:4. The cell line was susceptible to isolates of the M and U North American genotypes of infectious hematopoietic necrosis virus (IHNV), and to isolates of genotypes I, IVa, and IVb of viral hemorrhagic septicemia virus (VHSV). In contrast, the cell line was refractory to infection by 2 North American isolates of infectious pancreatic necrosis virus (IPNV) from serotypes A1 and A9. This cell line provides a new laboratory tool, will allow further investigation into viral diseases of burbot and possibly other species, and is the first immortalized cell line reported from a species in the Gadidae (cod) family.

  19. Spatio-temporal risk factors for viral haemorrhagic septicaemia (VHS) in Danish aquaculture.

    PubMed

    Bang Jensen, Britt; Ersbøll, Annette Kjær; Korsholm, Henrik; Skall, Helle Frank; Olesen, Niels Jørgen

    2014-05-13

    Viral haemorrhagic septicaemia (VHS) is an economically very important fish disease in the northern hemisphere. When the VHS virus was first isolated in Denmark 50 yr ago, more than 80% of the 800 Danish fish farms were considered to be infected, but vigilant surveillance and eradication programmes led to a drastic reduction in prevalence, and finally, to complete eradication of VHS. Denmark thus obtained official status as an approved VHS-free member state within the European Union in November 2013. Data on outbreaks within the country have been collected since 1970, and here we combined these data with the geographical coordinates of fish farms to identify clusters of high disease prevalence and other risk factors. Our analyses revealed a statistically significant cluster in the southwestern part of the country, which persisted throughout the study period. Being situated within such a cluster was a significant risk factor for VHS. For freshwater rainbow trout farms situated inland, the number of upstream farms was a determining risk factor for VHS, as was distance to the nearest VHS-infected farm and year. Whether the farm used fresh or marine water in production did not have any influence on the risk of VHS, when accounting for whether the farm was situated inside a cluster of high risk. This information can be used when implementing risk-based surveillance programmes.

  20. Spatio-temporal risk factors for viral haemorrhagic septicaemia (VHS) in Danish aquaculture.

    PubMed

    Bang Jensen, Britt; Ersbøll, Annette Kjær; Korsholm, Henrik; Skall, Helle Frank; Olesen, Niels Jørgen

    2014-05-13

    Viral haemorrhagic septicaemia (VHS) is an economically very important fish disease in the northern hemisphere. When the VHS virus was first isolated in Denmark 50 yr ago, more than 80% of the 800 Danish fish farms were considered to be infected, but vigilant surveillance and eradication programmes led to a drastic reduction in prevalence, and finally, to complete eradication of VHS. Denmark thus obtained official status as an approved VHS-free member state within the European Union in November 2013. Data on outbreaks within the country have been collected since 1970, and here we combined these data with the geographical coordinates of fish farms to identify clusters of high disease prevalence and other risk factors. Our analyses revealed a statistically significant cluster in the southwestern part of the country, which persisted throughout the study period. Being situated within such a cluster was a significant risk factor for VHS. For freshwater rainbow trout farms situated inland, the number of upstream farms was a determining risk factor for VHS, as was distance to the nearest VHS-infected farm and year. Whether the farm used fresh or marine water in production did not have any influence on the risk of VHS, when accounting for whether the farm was situated inside a cluster of high risk. This information can be used when implementing risk-based surveillance programmes. PMID:24991736

  1. In vitro neutralization of viral hemorrhagic septicemia virus by plasma from immunized zebrafish.

    PubMed

    Chinchilla, Blanca; Gomez-Casado, Eduardo; Encinas, Paloma; Falco, Alberto; Estepa, Amparo; Coll, Julio

    2013-03-01

    We studied humoral long-term adaptive viral neutralization responses in zebrafish (Danio rerio), an increasingly useful vertebrate model for viral diseases actually limited by the absence of standardized anti-zebrafish immunoglobulin M (IgM) antibodies. We established an alternative method, similar to those used in other fish, to achieve a first estimation of zebrafish anti-viral antibody-like responses. We used the viral hemorrhagic septicemia virus (VHSV) model because, although protection after this non-natural infection was demonstrated in cold-acclimatized zebrafish, little is known about their induced anti-VHSV antibody-like responses. Therefore, we first optimized a micro-neutralization method based on immunostaining VHSV-infected fish cell monolayers to detect zebrafish neutralizing activity in plasma samples in one day. We then used the method to measure the specific anti-VHSV neutralization in plasma obtained from individual zebrafish under various VHSV challenges or immunization protocols. The neutralizing activity was inhibited by protein A-sepharose and rabbit anti-zebrafish IgM antibodies, suggesting the implication of IgM zebrafish antibodies in such responses. To our knowledge, this is the first report to demonstrate detectable and significant VHSV neutralization titers in zebrafish surviving VHSV infections. This micro-method might be useful, not only for the follow-up of infection/vaccine development in the zebrafish/VHSV model in particular, but also for similar work involving other in vitro neutralizable zebrafish pathogens. This technique might also further the development of alternative ELISA assay methods to measure specific immunoglobulins in zebrafish.

  2. Complete Protection against Influenza Virus H1N1 Strain A/PR/8/34 Challenge in Mice Immunized with Non-Adjuvanted Novirhabdovirus Vaccines

    PubMed Central

    Rouxel, Ronan N.; Mérour, Emilie; Biacchesi, Stéphane; Brémont, Michel

    2016-01-01

    Novirhabdoviruses like Viral Hemorrhagic Septicemia Virus (VHSV) and Infectious Hematopoietic Necrosis Virus (IHNV) are fish-infecting Rhabdoviruses belonging to the Mononegavirales order. By reverse genetics, we previously showed that a recombinant VHSV expressing the West Nile Virus (WNV) E glycoprotein could serve as a vaccine platform against WNV. In the current study, we aimed to evaluate the potential of the Novirhabdovirus platform as a vaccine against influenza virus. Recombinant Novirhabdoviruses, rVHSV-HA and rIHNV-HA, expressing at the viral surface the hemagglutinin HA ectodomain were generated and used to immunized mice. We showed that mice immunized with either, rVHSV-HA or rIHNV-HA, elicited a strong neutralizing antibody response against influenza virus. A complete protection was conferred to the immunized mice when challenged with a lethal dose of influenza H1N1 A/PR/8/34 virus. Furthermore we showed that although acting as inert antigen in mice, since naturally inactivated over 20°C, mice immunized with rVHSV-HA or rIHNV-HA in the absence of adjuvant were also completely protected from a lethal challenge. Novirhabdoviruses platform are of particular interest as vaccines for mammals since they are cost effective to produce, relatively easy to generate and very effective to protect immunized animals. PMID:27711176

  3. Detection of Viral Hemorrhagic Septicemia Virus by Quantitative Reverse Transcription Polymerase Chain Reaction from Two Fish Species at Two Sites in Lake Superior

    USGS Publications Warehouse

    Cornwell, Emily R.; Eckerlin, Geofrey E.; Getchell, Rodman G.; Groocock, Geoffrey H.; Thompson, Tarin M.; Batts, William N.; Casey, Rufina N.; Kurath, Gael; Winton, James R.; Bowser, Paul R.; Bain, Mark B.; Casey, James W.

    2011-01-01

    Viral hemorrhagic septicemia virus (VHSV) was first detected in the Laurentian Great Lakes in 2005 during a mortality event in the Bay of Quinte, Lake Ontario. Subsequent analysis of archived samples determined that the first known isolation of VHSV in the Laurentian Great Lakes was from a muskellunge Esox masquinongy collected in Lake St. Clair in 2003. By the end of 2008, mortality events and viral isolations had occurred in all of the Laurentian Great Lakes except Lake Superior. In 2009, a focused disease surveillance program was designed to determine whether VHSV was also present in Lake Superior. In this survey, 874 fish from 7 sites along the U.S. shoreline of Lake Superior were collected during June 2009. Collections were focused on nearshore species known to be susceptible to VHSV. All fish were dissected individually by using aseptic techniques and were tested for the presence of VHSV genetic material by use of a quantitative reverse transcription (qRT) polymerase chain reaction (PCR) targeting the viral nucleoprotein gene. Seventeen fish from two host species at two different sites tested positive at low levels for VHSV. All attempts to isolate virus in cell culture were unsuccessful. However, the presence of viral RNA was confirmed independently in five fish by using a nested PCR that targeted the glycoprotein (G) gene. Partial G gene sequences obtained from three fish were identical to the corresponding sequence from the original 2003 VHSV isolate (MI03) from muskellunge. These detections represent the earliest evidence for the presence of VHSV in Lake Superior and illustrate the utility of the highly sensitive qRT-PCR assay for disease surveillance in aquatic animals.

  4. An ELISA for detection of trout antibodies to viral haemorrhagic septicemia virus using recombinant fragments of their viral G protein.

    PubMed

    Encinas, P; Gomez-Casado, E; Estepa, A; Coll, J M

    2011-09-01

    An enzyme linked immunosorbent assay (ELISA) method to study serum antibodies to viral haemorrhagic septicemia virus (VHSV) was designed by using recombinant fragments of their G protein. By using this fragment-ELISA, we describe the binding of antibodies against recombinant G fragments of 45-445 amino acids present in VHSV-hyperimmunized trout sera. Fragments were designed by taking into account their tridimensional pH-dependent structure and functional domains. Sera were obtained from hyperimmunized trout following 4-5 intraperitoneal injections of VHSV antigens by using Freund's or saponin adjuvants. Sera from different hyperimmunized trout differed quantitatively rather than qualitatively in their recognition of solid-phase frg11 (56-110), frg12 (65-109), frg13 (97-167), frg14 (141-214), frg15 (65-250), frg16 (252-450) and G (G21-465) by Western blot and ELISA. However, titres were higher when using frg11, frg15 or frg16, rather than G21-465, suggesting higher accessibility to G epitopes. Further knowledge of the antigenicity of the G protein of rhabdoviruses by using fragments might be used to improve current vaccines. On the other hand, they might be used to dissect the trout antibody response to VHSV infections, to complement in vitro neutralizing assays, and/or to quantitate anti-VHSV antibodies in VHSV-infected/vaccinated trout, other fish and/or other body fluids such as mucus.

  5. Episootiology of viral hemorrhagic septicemia virus in Pacific herring from the spawn-on-kelp fishery in Prince William Sound, Alaska, USA

    USGS Publications Warehouse

    Hershberger, P.K.; Kocan, R.M.; Elder, N.E.; Meyers, T.R.; Winton, J.R.

    1999-01-01

    Both the prevalence and tissue titer of viral hemorrhagic septicemia virus (VHSV) increased in Pacific herring Clupea pallasi following their introduction into net pens (pounds) used in the closed pound spawn-on-kelp (SOK) fishery in Prince William Sound, Alaska. VHSV was also found in water samples from inside and outside the SOK pounds after herring had been confined for several days; however, water samples taken near wild free-ranging, spawning herring either failed to test positive or tested weakly positive for virus. Little or no virus was found in tissue samples from free-ranging, spawning herring captured from the vicinity of the pounds, nor did the prevalence of VHSV increase following spawning as it did in impounded herring. The data indicated that increased prevalences of VHSV were correlated with confinement of herring for the closed pound SOK fishery and that infection was spread within the pounds through waterborne exposure to virus particles originating from impounded fish. In addition, pounds containing predominantly young fish had higher prevalences of VHSV, suggesting that older fish may be partially immune, perhaps as a result of previous infection with the virus. Operation of SOK pounds during spawning seasons in which young herring predominate may amplify the disease and possibly exacerbate the population fluctuations observed in wild herring stocks.

  6. Epizootiology of viral hemorrhagic septicemia virus in Pacific herring from the spawn-on-kelp fishery in Prince William Sound, Alaska, USA

    USGS Publications Warehouse

    Hershberger, P.K.; Kocan, R.M.; Elder, N.E.; Meyers, T.R.; Winton, J.R.

    1999-01-01

    Both the prevalence and tissue titer of viral hemorrhagic septicemia virus (VHSV) increased in Pacific herring Clupea pallasi following their introduction into net pens (pounds) used in the closed pound spawn-on-kelp (SOK) fishery in Prince William Sound, Alaska. VHSV was also found in water samples from inside and outside the SOK pounds after herring had been confined for several days; however, water samples taken near wild free-ranging, spawning herring either failed to test positive or tested weakly positive for virus. Little or no virus was found in tissue samples from free-ranging, spawning herring captured from the vicinity of the pounds, nor did the prevalence of VHSV increase following spawning as it did in impounded herring. The data indicated that increased prevalences of VHSV were correlated with confinement of herring for the closed pound SOK fishery and that infection was spread within the pounds through waterborne exposure to virus particles originating from impounded fish. In addition, pounds containing predominantly young fish had higher prevalences of VHSV, suggesting that older fish may be partially immune, perhaps as a result of previous infection with the virus. Operation of SOK pounds during spawning seasons in which young herring predominate may amplify the disease and possibly exacerbate the population fluctuations observed in wild herring stocks.

  7. Neonatal Klebsiella Septicaemia in Ibadan: Implications for Neonatal Care in Developing Countries.

    ERIC Educational Resources Information Center

    Omokhodion, S. I.; And Others

    1993-01-01

    The antecedent events, clinical features, prevalence, and complications of neonatal Klebsiella septicaemia in 73 infants admitted to a special care baby unit in Nigeria are retrospectively reviewed and compared with those of 72 infants who had no risk factors for sepsis admitted to the same unit during the same period. A nosocomial acquisition of…

  8. Increased Risk of Stroke after Septicaemia: A Population-Based Longitudinal Study in Taiwan

    PubMed Central

    Lee, Jiunn-Tay; Chung, Wen Ting; Lin, Jin-Ding; Peng, Giia-Sheun; Muo, Chih-Hsin; Lin, Che-Chen; Wen, Chi-Pang; Wang, I-Kuan; Tseng, Chun-Hung; Kao, Chia-Hung; Hsu, Chung Y.

    2014-01-01

    Inflammation and infection have been noted to increase stroke risk. However, the association between septicaemia and increased risk of stroke remains unclear. This population-based cohort study, using a National Health Insurance database, aimed to investigate whether patients with septicaemia are predisposed to increased stroke risk. The study included all patients hospitalised for septicaemia for the first time between 2000 and 2003 without prior stroke. Patients were followed until the end of 2010 to evaluate incidence of stroke. An age-, gender- and co-morbidities-matched cohort without prior stroke served as the control. Cox’s proportional hazards regressions were used to assess differences in stroke risk between groups. Based on hazard ratios (HRs), patients with septicaemia had greater stroke risk, especially in the younger age groups (age <45: HR = 4.16, 95% CI: 2.39–7.24, p<0.001; age 45–64: HR = 1.76, 95% CI: 1.41–2.19, p<0.001; age ≥65: HR = 1.05, 95% CI: 0.91–1.22, p>0.05). Haemorrhagic stroke was the dominant type (ischaemic stroke: HR = 1.20, 95% CI: 1.06–1.37, p<0.01; haemorrhagic stroke: HR = 1.82, 95% CI: 1.35–2.46, p<0.001) and patients without co-morbidities were at slightly higher risk (without co-morbidities: HR = 1.49, 95% CI: 1.02–2.17, p<0.05; with co-morbidities: HR = 1.24, 95% CI: 1.10–1.41, p<0.001). The impact of septicaemia on stroke risk was highest within 6 months of the event and gradually declined over time. Our results suggest that septicaemia is associated with an increase in stroke risk, which is greatest in haemorrhagic stroke. Closer attention to patients with history of septicaemia may be warranted for stroke preventive measures, especially for younger patients without co-morbidities. PMID:24586739

  9. A survey of fish viruses isolated from wild marine fishes from the coastal waters of southern Korea.

    PubMed

    Kim, Wi-Sik; Choi, Shin-Young; Kim, Do-Hyung; Oh, Myung-Joo

    2013-11-01

    A survey was conducted to investigate viral infection in 253 wild marine fishes harvested in the southern coastal area of Korea from 2010 to 2012. The fish that were captured by local anglers were randomly bought and sampled for virus examination. The samples were tested for presence of virus by virus isolation with FHM, FSP, and BF-2 cells and molecular methods (polymerase chain reaction and sequencing). Of the 253 fish sampled, 9 fish were infected with virus. Aquabirnaviruses (ABVs), Viral hemorrhagic septicemia virus (VHSV), and Red seabream iridovirus (RSIV) were detected in 7, 1, and 1 fish, respectively. Molecular phylogenies demonstrated the detected viruses (ABV, VHSV, and RSIV) were more closely related to viruses reported of the same type from Korea and Japan than from other countries, suggesting these viruses may be indigenous to Korean and Japanese coastal waters.

  10. Host and geographic range extensions of the North American strain of viral hemorrhagic septicemia virus

    USGS Publications Warehouse

    Hedrick, R.P.; Batts, W.N.; Yun, S.; Traxler, G.S.; Kaufman, J.; Winton, J.R.

    2003-01-01

    Viral hemorrhagic septicemia virus (VHSV) was isolated from populations of Pacific sardine Sardinops sagaxfrom the coastal waters of Vancouver Island, British Columbia, Canada, and central and southern California, USA. The virus was also isolated from Pacific mackerel Scomber japonicus in southern California, from eulachon or smeltThaleichthys pacificus, and surf smelt Hypomesus pretiosus pretiosus from Oregon, USA. Mortality and skin lesions typical of viral hemorrhagic septicemia in other marine fish species were observed among sardine in Canada and in a few surf smelt from Oregon, but the remaining isolates of VHSV were obtained from healthy appearing fish. The prevalence of VHSV among groups of apparently healthy sardine, mackerel and smelt ranged from 4 to 8% in California and Oregon. A greater prevalence of infection (58%) occurred in groups of sardine sampled in Canada that sustained a naturally occurring epidemic during 1998-99. A captive group of surf smelt in Oregon exhibited an 81% prevalence of infection with clinical signs in only a few fish. The new isolates were confirmed as North American VHSV and were closely related based on comparisons of the partial nucleotide sequence of the glycoprotein (G) gene. The VHSV isolates from sardine in Canada and California were the most closely related, differing from isolates obtained from other marine fish species and salmonids in British Columbia, Canada, Alaska and Washington, USA. These new virus isolations extend both the known hosts (sardine, mackerel and 2 species of smelt) and geographic range (Oregon and California, USA) of VHSV.

  11. Molecular epidemiology of viral hemorrhagic septicemia virus in the Great Lakes region

    USGS Publications Warehouse

    Winton, James; Kurath, Gael; Batts, William

    2008-01-01

    Viral hemorrhagic septicemia virus (VHSV) is considered by many nations and international organizations to be one of the most important viral pathogens of finfish (Office International des Epizooties 2007). For several decades following its initial characterization in the 1950s, VHSV was thought to be limited to Europe where it was regarded as an endemic pathogen of freshwater fish that was especially problematic for farmed rainbow trout, an introduced species (Wolf 1988; Smail 1999). Subsequently, it was shown that VHSV was present among many species of marine and anadromous fishes in both the Pacific and Atlantic Oceans where it has been associated with substantial mortality among both wild and cultured fish (Meyers and Winton 1995; Skall et al. 2005).

  12. Temporal Variation in Viral Hemorrhagic Septicemia Virus Antibodies in Freshwater Drum (Aplodinotus grunniens) Indicates Cyclic Transmission in Lake Winnebago, Wisconsin

    PubMed Central

    Wilson-Rothering, Anna; Marcquenski, Susan; Koenigs, Ryan; Bruch, Ronald; Kamke, Kendall; Isermann, Daniel; Thurman, Andrew; Toohey-Kurth, Kathy

    2015-01-01

    Viral hemorrhagic septicemia virus (VHSV) is an emerging pathogen that causes mass mortality in multiple fish species. In 2007, the Great Lakes freshwater strain, type IVb, caused a large die-off of freshwater drum (Aplodinotus grunniens) in Lake Winnebago, Wisconsin, USA. To evaluate the persistence and transmission of VHSV, freshwater drum from Lake Winnebago were tested for antibodies to the virus using recently developed virus neutralization (VN) and enzyme-linked immunosorbent (ELISA) assays. Samples were also tested by real-time reverse transcription-PCR (rRT-PCR) to detect viral RNA. Of 548 serum samples tested, 44 (8.03%) were positive by VN (titers ranging from 1:16 to 1:1,024) and 45 (8.21%) were positive by ELISA, including 7 fish positive by both assays. Antibody prevalence increased with age and was higher in one northwestern area of Lake Winnebago than in other areas. Of 3,864 tissues sampled from 551 fish, 1 spleen and 1 kidney sample from a single adult female fish collected in the spring of 2012 tested positive for VHSV by rRT-PCR, and serum from the same fish tested positive by VN and ELISA. These results suggest that VHSV persists and viral transmission may be active in Lake Winnebago even in years following outbreaks and that wild fish may survive VHSV infection and maintain detectable antibody titers while harboring viral RNA. Influxes of immunologically naive juvenile fish through recruitment may reduce herd immunity, allow VHSV to persist, and drive superannual cycles of transmission that may sporadically manifest as fish kills. PMID:26135873

  13. Septicaemia caused by Edwardsiella tarda and Plesiomonas shigelloides in captive penguin chicks.

    PubMed

    Nimmervoll, H; Wenker, C; Robert, N; Albini, S

    2011-03-01

    Three cases of fatal septicaemia due to Plesiomonas shigelloides and one due to Edwardsiella tarda were diagnosed in newborn penguins from the Basle Zoo, Switzerland from 2003 to 2007. The affected penguins were of two different species (king penguin, Aptenodytes patagonicus, and African penguin, Spheniscus demersus) and between 2 and 10 days old at the time of death. The causative agents, E. tarda and P. shigelloides are ubiquitous bacteria which are reported to be present in the normal intestinal flora of wild and captive aquatic animals, including penguins. Their occurrence and infectious potential is discussed. PMID:21360449

  14. Septicaemia caused by Edwardsiella tarda and Plesiomonas shigelloides in captive penguin chicks.

    PubMed

    Nimmervoll, H; Wenker, C; Robert, N; Albini, S

    2011-03-01

    Three cases of fatal septicaemia due to Plesiomonas shigelloides and one due to Edwardsiella tarda were diagnosed in newborn penguins from the Basle Zoo, Switzerland from 2003 to 2007. The affected penguins were of two different species (king penguin, Aptenodytes patagonicus, and African penguin, Spheniscus demersus) and between 2 and 10 days old at the time of death. The causative agents, E. tarda and P. shigelloides are ubiquitous bacteria which are reported to be present in the normal intestinal flora of wild and captive aquatic animals, including penguins. Their occurrence and infectious potential is discussed.

  15. Cardiac rupture caused by Staphylococcus aureus septicaemia and pericarditis: an incidental finding

    PubMed Central

    Osula, S; Lowe, R; Perry, R

    2001-01-01

    A 35 year old woman with a long history of intravenous drug abuse presented to a local hospital with severe anaemia, fever, raised markers of inflammation, and positive blood cultures for Staphylococcus aureus. She responded to treatment with antibiotics with improvement in her symptoms and markers of inflammation. Four weeks later a "routine" echocardiogram showed a rupture of her left ventricular apex and a large pseudoaneurysm. There had been no deterioration in her symptoms or haemodynamic status to herald this new development. It was successfully repaired surgically and the patient made a good recovery.


Keywords: ventricular rupture; pseudoaneurysm; staphylococcal septicaemia PMID:11179283

  16. Production and characterization of streptomycin dependent mutants of Pasteurella multocida from bovine haemorrhagic septicaemia.

    PubMed Central

    de Alwis, M C; Carter, G R; Chengappa, M M

    1980-01-01

    A large number of streptomycin dependent mutants were produced from bovine haemorrhagic septicaemia strains of Pasteurella multocida. The mutants required a minimum concentration of 25-50 microgram/mL streptomycin for growth and tolerated a concentration of 200 mg/mL. These mutants were avirulent to mice, when inoculated alone, but some mutants killed mice when inoculated with streptomycin. Biochemically all mutants were uniform and similar to the wild type. Most mutants were stable, but a few produced streptomycin independent revertants. The rate of reversion varied with each mutant. Most revertants were highly virulent for mice, some totally avirulant and a few relatively avirulent. PMID:6778598

  17. Pyogranulomatous myocarditis due to Staphylococcus aureus septicaemia in two harbour porpoises (Phocoena phocoena).

    PubMed

    Siebert, U; Müller, G; Desportes, G; Weiss, R; Hansen, K; Baumgärtner, W

    2002-03-01

    Staphylococcus aureus septicaemia was diagnosed in a dead, stranded harbour porpoise from the German Baltic Sea and in a live harbour porpoise by-caught in inner Danish waters and taken into captivity. Lesions included pyogranulomatous myocarditis, necrotising suppurative bronchopneumonia, pyelonephritis, osteomyelitis and leptomeningitis, and abscesses in lymph nodes and skeletal muscles. The captive animal had fibrinous suppurative epicarditis and pyogranulomatous myocarditis with abscesses. In both animals the organism was suspected to have entered through skin lesions or via the respiratory tract. PMID:11918049

  18. Identification and characterization of pathogen to bacterial septicaemia in cultured turbot, Scophthalmus maximus

    NASA Astrophysics Data System (ADS)

    Qin, Guomin; Zhang, Xiaojun; Chen, Cuizhen; Fang, Hai; Zhan, Wenbin

    2007-10-01

    Bacteria-infected turbots Scophthalmus maximus with septicaemia were examined between 2001 and 2004 in aspects of the conditions of disease occurrence, clinical syndromes and pathological changes. The phenotypic information of pathogenic bacteria was studied, including morphology, physiological and biochemical characteristics, and the mol% G+C of the DNA. In addition, representative strains (S010623-1, LH031120-1) were selected for molecular identification by partial 16S rRNA gene sequencing. The results show that the isolates (LH031120-1 to LH031120-6, HT040308-1 to HT040308-6, HT040620-1 to HT040620-6) from three farms were identified as Edwardsiella tarda. The isolates (S010610-1 to S010610-10, S010623-1 to S010623-20) from one farm were identified as Listonella anguillarum. We conducted studies on the pathogenicity of isolates by artificial infection, and revealed all infected groups in morbidity and mortality. The septicaemia infected turbot showed a syndrome similar to that of the naturally infected fish. Antibiotic sensitivity showed that of 37 antimicrobial agents, E. tarda was sensitive to 27 agents, and L. anguillarum was sensitive to 21 agents.

  19. Evaluation of the Efficacy of Iodophor Disinfection of Walleye and Northern Pike Eggs to Eliminate Viral Hemorrhagic Septicemia Virus

    USGS Publications Warehouse

    Tuttle-Lau, M.T.; Phillips, K.A.; Gaikowski, M.P.

    2009-01-01

    Viral hemorrhagic septicemia virus (VHSv) is a serious fish pathogen that has been responsible for large-scale fish kills in the Great Lakes since 2005. It causes high mortality and resulting outbreaks have severe economic consequences for aquaculture. Iodophor disinfection of salmonid eggs is a standard hatchery practice to reduce the risk of pathogen transfer during gamete collection ('spawning') operations and is thus a leading candidate for reducing VHSv transmission during and after spawning of nonsalmonid fishes. However, before it is incorporated by hatcheries during nonsalmonid fish spawning efforts, its safety and effectiveness needs to be evaluated. The USGS Fact Sheet 2009-3107, 'Evaluation of the Efficacy of Iodophor Disinfection of Walleye and Northern Pike Eggs to Eliminate Viral Hemorrhagic Septicemia Virus' presents the results of a study to assess the effectiveness of iodophor disinfection for eliminating VHSv (strain IVb) from fertilized eggs of walleye and northern pike intentionally challenged with VHSv following egg fertilization. Walleye and northern pike egg survival (hatch) following iodophor egg disinfection also was assessed.

  20. Comparative Genomic Analysis of Asian Haemorrhagic Septicaemia-Associated Strains of Pasteurella multocida Identifies More than 90 Haemorrhagic Septicaemia-Specific Genes

    PubMed Central

    Moustafa, Ahmed M.; Seemann, Torsten; Gladman, Simon; Adler, Ben; Harper, Marina; Boyce, John D.; Bennett, Mark D.

    2015-01-01

    Pasteurella multocida is the primary causative agent of a range of economically important diseases in animals, including haemorrhagic septicaemia (HS), a rapidly fatal disease of ungulates. There is limited information available on the diversity of P. multocida strains that cause HS. Therefore, we determined draft genome sequences of ten disease-causing isolates and two vaccine strains and compared these genomes using a range of bioinformatic analyses. The draft genomes of the 12 HS strains were between 2,298,035 and 2,410,300 bp in length. Comparison of these genomes with the North American HS strain, M1404, and other available P. multocida genomes (Pm70, 3480, 36950 and HN06) identified a core set of 1,824 genes. A set of 96 genes was present in all HS isolates and vaccine strains examined in this study, but absent from Pm70, 3480, 36950 and HN06. Moreover, 59 genes were shared only by the Asian B:2 strains. In two Pakistani isolates, genes with high similarity to genes in the integrative and conjugative element, ICEPmu1 from strain 36950 were identified along with a range of other antimicrobial resistance genes. Phylogenetic analysis indicated that the HS strains formed clades based on their country of isolation. Future analysis of the 96 genes unique to the HS isolates will aid the identification of HS-specific virulence attributes and facilitate the development of disease-specific diagnostic tests. PMID:26151935

  1. MLST typing of Pasteurella multocida associated with haemorrhagic septicaemia and development of a real-time PCR specific for haemorrhagic septicaemia associated isolates.

    PubMed

    Petersen, Andreas; Bisgaard, Magne; Townsend, Kirsty; Christensen, Henrik

    2014-06-01

    Two serovars of Pasteurella multocida, B:2 and E:2, have been reportedly associated with haemorrhagic septicaemia (HS), a peracute and devastating disease mainly affecting cattle and water buffaloes. We multilocus sequence typed (MLST) 64 isolates of P. multocida including 55 associated with HS and found that they mainly included sequence type (ST) 122 (n=50) and rarely ST63 (n=1), ST147 (n=2) and ST162 (n=2) compared to other members of the species isolated from other lesion types and hosts. Single-nucleotide polymorphisms suitable for specific detection of STs associated with HS were detected in the est gene. A new HS-est-RT-PCR (est indicating the target gene) specifically detected ST122, ST63, ST147 and ST162 associated with HS. The new HS-est-RT-PCR did not detect strains of ST151 with capsular type D isolated from pigs that were found positive with a previously published HS PCR detection method. The new HS-est-RT-PCR represents a fast and specific detection of the specific types of P. multocida involved in HS. The HS-est-RT-PCR developed in the current study seems to more accurately identify isolates of P. multocida associated with HS compared to PCR detection methods previously published.

  2. Corexit 9500 inactivates two enveloped viruses of aquatic animals but enhances the infectivity of a nonenveloped fish virus.

    PubMed

    Pham, P H; Huang, Y J; Chen, C; Bols, N C

    2014-02-01

    The effects of Corexit 9500, a dispersant used to clean up oil spills, on invertebrates, lower vertebrates, birds, and human health have been examined, but there is a significant lack of study of the effect of this dispersant on aquatic viruses. In this study, the effects of Corexit 9500 on four aquatic viruses of differing structural composition were examined. Corexit 9500 reduced the titer of the enveloped viral hemorrhagic septicemia virus (VHSV) at all concentrations (10% to 0.001%) examined. The titer of frog virus 3 (FV3), a virus with both enveloped and nonenveloped virions, was reduced only at the high Corexit 9500 concentrations (10% to 0.1%). Corexit 9500 was unable to reduce the titer of nonenveloped infectious pancreatic necrosis virus (IPNV) but enhanced the titer of chum salmon reovirus (CSV) by 2 to 4 logs. With the ability to inactivate enveloped viruses and possibly enhance some nonenveloped viruses, Corexit 9500 has the potential to alter the aquatic virosphere.

  3. Post transfusion septicaemia 1980-1989: importance of donor arm cleansing.

    PubMed Central

    Puckett, A.; Davison, G.; Entwistle, C. C.; Barbara, J. A.

    1992-01-01

    AIMS: To determine the prevalence of Pseudomonas fluorescens on the arms of blood donors, and to elucidate one possible cause for its predominance (60% of cases during 1980-89) in exogenous post transfusion septicaemia (PTS). METHODS: Skin swabs were taken from the arms of 782 blood donors and cultured on to heated blood agar. After incubation, Oxidase reagent and the Gram stain were used to select non-fermentative Gram negative rods, which were then subcultured and identified using the Analytical Profile System (API) 20 NE system. RESULTS: Non-fermentative Gram negative rods were found on the arms of 11.7% of donors, Pseudomonas spp on 1.0%, and Ps fluorescens on the arms of 0.3% of donors. CONCLUSIONS: This evidence emphasises the absolute requirement for efficient skin cleansing of blood donors' arms to minimise the risk of exogenous PTS. PMID:1541697

  4. Chronic and persistent viral hemorrhagic septicemia virus infections in Pacific herring

    USGS Publications Warehouse

    Hershberger, P.K.; Gregg, J.L.; Grady, C.A.; Taylor, L.; Winton, J.R.

    2010-01-01

    Chronic viral hemorrhagic septicemia virus (VHSV) infections were established in a laboratory stock of Pacific herring Clupea pallasii held in a large-volume tank supplied with pathogenfree seawater at temperatures ranging from 6.8 to 11.6??C. The infections were characterized by viral persistence for extended periods and near-background levels of host mortality. Infectious virus was recovered from mortalities occurring up to 167 d post-exposure and was detected in normal-appearing herring for as long as 224 d following initial challenge. Geometric mean viral titers were generally as high as or higher in brain tissues than in pools of kidney and spleen tissues, with overall prevalence of infection being higher in the brain. Upon re-exposure to VHSV in a standard laboratory challenge, negligible mortality occurred among groups of herring that were either chronically infected or fully recovered, indicating that survival from chronic manifestations conferred protection against future disease. However, some survivors of chronic VHS infections were capable of replicating virus upon re-exposure. Demonstration of a chronic manifestation of VHSV infection among Pacific herring maintained at ambient seawater temperatures provides insights into the mechanisms by which the virus is maintained among populations of endemic hosts. ?? 2010 Inter-Research.

  5. Chronic and persistent viral hemorrhagic septicemia virus infections in Pacific herring

    USGS Publications Warehouse

    Hershberger, Paul K.; Gregg, Jacob L.; Winton, James R.; Grady, Cortney A.; Taylor, L.

    2010-01-01

    Chronic viral hemorrhagic septicemia virus (VHSV) infections were established in a laboratory stock of Pacific herring Clupea pallasii held in a large-volume tank supplied with pathogen-free seawater at temperatures ranging from 6.8 to 11.6°C. The infections were characterized by viral persistence for extended periods and near-background levels of host mortality. Infectious virus was recovered from mortalities occurring up to 167 d post-exposure and was detected in normal-appearing herring for as long as 224 d following initial challenge. Geometric mean viral titers were generally as high as or higher in brain tissues than in pools of kidney and spleen tissues, with overall prevalence of infection being higher in the brain. Upon re-exposure to VHSV in a standard laboratory challenge, negligible mortality occurred among groups of herring that were either chronically infected or fully recovered, indicating that survival from chronic manifestations conferred protection against future disease. However, some survivors of chronic VHS infections were capable of replicating virus upon re-exposure. Demonstration of a chronic manifestation of VHSV infection among Pacific herring maintained at ambient seawater temperatures provides insights into the mechanisms by which the virus is maintained among populations of endemic hosts.

  6. Teeth grinding, tongue and lip biting in a 24-month-old boy with meningococcal septicaemia. Report of a case.

    PubMed

    Coyne, B M C; Montague, T

    2002-07-01

    This paper describes the management of a 24-month-old boy who presented with self-inflicted trauma to his lower lip and tongue, and teeth grinding, 21 days after developing meningococcal septicaemia. A decision to observe and prescribe palliative therapy was made. Extraction of the lower right deciduous canine, which had become non-vital, possibly due to bruxism, was carried out. PMID:12121539

  7. Septicaemia secondary to infection by Corynebacterium macginleyi in an Indian python (Python molurus).

    PubMed

    Martínez, Jorge; Segura, Pablo; García, David; Aduriz, Gorka; Ibabe, José C; Peris, Bernardo; Corpa, Juan M

    2006-09-01

    A seven-year-old female Indian python (Python molurus) weighing about 35kg was euthanased after several clinical episodes of stomatitis, pneumonia, ophthalmitis and dystocia over a period of four years. The animal had been maintained in a terrarium in a circus truck at an adequate temperature. During shows, however, the snake was considered to be exposed to stressful conditions for several hours at a time at low temperatures and with noise and bright lights. A post-mortem examination indicated ulcerative stomatitis, osteomyelitis, severe pneumonia and numerous granulomata and multifocal necrosis in stomach and spleen. Corynebacterium macginleyi was isolated in pure culture from the ulcerative stomatitis, and mixed with Stenotrophomonas maltophilia from the lungs and spleen. The findings indicated that the snake had died from a septicaemic process caused by C. macginleyi, probably originating from the stomatitis. The role of S. maltophilia as a secondary agent is discussed. The stress of the circus show and poor husbandry may have predisposed the animal to infection and septicaemia. This is the first report of C. macginleyi causing disease in a snake.

  8. Experimental infection studies demonstrating Atlantic salmon as a host and reservoir of viral hemorrhagic septicemia virus type IVa with insights into pathology and host immunity

    USGS Publications Warehouse

    Lovy, Jan; Piesik, P.; Hershberger, P.K.; Garver, K.A.

    2013-01-01

    In British Columbia, Canada (BC), aquaculture of finfish in ocean netpens has the potential for pathogen transmission between wild and farmed species due to the sharing of an aquatic environment. Viral hemorrhagic septicemia virus (VHSV) is enzootic in BC and causes serious disease in wild Pacific herring, Clupea pallasii, which often enter and remain in Atlantic salmon, Salmo salar, netpens. Isolation of VHSV from farmed Atlantic salmon has been previously documented, but the effects on the health of farmed salmon and the wild fish sharing the environment are unknown. To determine their susceptibility, Atlantic salmon were exposed to a pool of 9 isolates of VHSV obtained from farmed Atlantic salmon in BC by IP-injection or by waterborne exposure and cohabitation with diseased Pacific herring. Disease intensity was quantified by recording mortality, clinical signs, histopathological changes, cellular sites of viral replication, expression of interferon-related genes, and viral tissue titers. Disease ensued in Atlantic salmon after both VHSV exposure methods. Fish demonstrated gross disease signs including darkening of the dorsal skin, bilateral exophthalmia, light cutaneous hemorrhage, and lethargy. The virus replicated within endothelial cells causing endothelial cell necrosis and extensive hemorrhage in anterior kidney. Infected fish demonstrated a type I interferon response as seen by up-regulation of genes for IFNα, Mx, and ISG15. In a separate trial infected salmon transmitted the virus to sympatric Pacific herring. The results demonstrate that farmed Atlantic salmon can develop clinical VHS and virus can persist in the tissues for at least 10 weeks. Avoiding VHS epizootics in Atlantic salmon farms would limit the potential of VHS in farmed Atlantic salmon, the possibility for further host adaptation in this species, and virus spillback to sympatric wild fishes.

  9. Flavimonas oryzihabitans septicaemia in a T-cell leukaemic child: a case report and review of the literature.

    PubMed

    Podbielski, A; Mertens, R; Ziebold, C; Kaufhold, A

    1990-03-01

    We describe the first case of septicaemia with Flavimonas oryzihabitans reported from Germany and possibly associated with colonisation of a venous port system. The patient, an 8-year-old T-cell leukaemic girl, was receiving a third course of chemotherapy before bone marrow transplantation. The cardinal symptom, fever, subsided when the venous port system for administration of drugs was no more used. The organism was tested extensively for characteristic biochemical features and antimicrobial susceptibility. We discuss the relevant literature and suggest the means of making a definitive microbiological diagnosis.

  10. Flavimonas oryzihabitans septicaemia in a T-cell leukaemic child: a case report and review of the literature.

    PubMed

    Podbielski, A; Mertens, R; Ziebold, C; Kaufhold, A

    1990-03-01

    We describe the first case of septicaemia with Flavimonas oryzihabitans reported from Germany and possibly associated with colonisation of a venous port system. The patient, an 8-year-old T-cell leukaemic girl, was receiving a third course of chemotherapy before bone marrow transplantation. The cardinal symptom, fever, subsided when the venous port system for administration of drugs was no more used. The organism was tested extensively for characteristic biochemical features and antimicrobial susceptibility. We discuss the relevant literature and suggest the means of making a definitive microbiological diagnosis. PMID:2181025

  11. The Socioeconomic Impacts of Clinically Diagnosed Haemorrhagic Septicaemia on Smallholder Large Ruminant Farmers in Cambodia.

    PubMed

    Kawasaki, M; Young, J R; Suon, S; Bush, R D; Windsor, P A

    2015-10-01

    Haemorrhagic septicaemia (HS) is an acute fatal infectious disease of mainly cattle and buffalo and outbreaks occur commonly in Cambodia. Disease outbreak reports were examined to select five villages from three provinces for a retrospective investigation of HS epidemiology and socioeconomic impact on smallholders, with an aim of identifying potential benefits from improving disease prevention through biosecurity and vaccination. The Village Animal Health Worker (VAHW) or Chief in each village and 66 affected smallholders were surveyed. At the village level, 24% of all households were affected with an estimated mean village herd morbidity of 10.1% and mortality of 28.8%. Affected farmers reported HS disease morbidity and mortality at 42.7% and 63.6% respectively. Buffalo had a higher morbidity (OR = 2.3; P = 0.003) and mortality (OR = 6.9; P < 0.001) compared with cattle, and unvaccinated large ruminants a higher morbidity (OR = 2.9; P = 0.001). The financial impact varied depending on whether the animal survived, provision of treatment, draught replacement and lost secondary income. The mean cost per affected household was USD 952.50 based on ownership of five large ruminants. The impact per affected animal was USD 375.00, reducing the pre-disease value by 66.1%. A partial budget revealed an overwhelming incentive for farmers to practice biannual vaccination, with a net benefit of USD 951.58 per household based on an annual disease incidence rate of 1. Sensitivity analysis showed that a net benefit of USD 32.42 remained based on an outbreak every 20 years. This study indicates HS can cause a catastrophic financial shock to smallholders and remains a critical constraint to improving large ruminant productivity and profitability. Addressing HS disease control requires a focus on improving smallholder farmer knowledge of biosecurity and vaccination and should be priority to stakeholders interested in addressing regional food insecurity and poverty reduction.

  12. vig-1, a New Fish Gene Induced by the Rhabdovirus Glycoprotein, Has a Virus-Induced Homologue in Humans and Shares Conserved Motifs with the MoaA Family

    PubMed Central

    Boudinot, Pierre; Massin, Pascale; Blanco, Mar; Riffault, Sabine; Benmansour, Abdenour

    1999-01-01

    We used mRNA differential display methodology to analyze the shift of transcription profile induced by the fish rhabdovirus, viral hemorrhagic septicemia virus (VHSV), in rainbow trout leukocytes. We identified and characterized a new gene which is directly induced by VHSV. This VHSV-induced gene (vig-1) encodes a 348-amino-acid protein. vig-1 is highly expressed during the experimental disease in lymphoid organs of the infected fish. Intramuscular injection of a plasmid vector expressing the viral glycoprotein results in vig-1 expression, showing that the external virus protein is sufficient for the induction. vig-1 expression is also obtained by a rainbow trout interferon-like factor, indicating that vig-1 can be induced through different pathways. Moreover, vig-1 is homologous to a recently described human cytomegalovirus-induced gene. Accordingly, vig-1 activation may represent a new virus-induced activation pathway highly conserved in vertebrates. The deduced amino acid sequence of vig-1 is significantly related to sequences required for the biosynthesis of metal cofactors. This suggests that the function of vig-1 may be involved in the nonspecific virus-induced synthesis of enzymatic cofactors of the nitric oxide pathway. PMID:9971762

  13. Emergence of viral hemorrhagic septicemia virus in the North American Great Lakes region is associated with low viral genetic diversity

    USGS Publications Warehouse

    Thompson, T.M.; Batts, W.N.; Faisal, M.; Bowser, P.; Casey, J.W.; Phillips, K.; Garver, K.A.; Winton, J.; Kurath, G.

    2011-01-01

    Viral hemorrhagic septicemia virus (VHSV) is a fish rhabdovirus that causes disease in a broad range of marine and freshwater hosts. The known geographic range includes the Northern Atlantic and Pacific Oceans, and recently it has invaded the Great Lakes region of North Ame­rica. The goal of this work was to characterize genetic diversity of Great Lakes VHSV isolates at the early stage of this viral emergence by comparing a partial glycoprotein (G) gene sequence (669 nt) of 108 isolates collected from 2003 to 2009 from 31 species and at 37 sites. Phylogenetic analysis showed that all isolates fell into sub-lineage IVb within the major VHSV genetic group IV. Among these 108 isolates, genetic diversity was low, with a maximum of 1.05% within the 669 nt region. There were 11 unique sequences, designated vcG001 to vcG011. Two dominant sequence types, vcG001 and vcG002, accounted for 90% (97 of 108) of the isolates. The vcG001 isolates were most widespread. We saw no apparent association of sequence type with host or year of isolation, but we did note a spatial pattern, in which vcG002 isolates were more prevalent in the easternmost sub-regions, including inland New York state and the St. Lawrence Seaway. Different sequence types were found among isolates from single disease outbreaks, and mixtures of types were evident within 2 isolates from ­individual fish. Overall, the genetic diversity of VHSV in the Great Lakes region was found to be extremely low, consistent with an introduction of a new virus into a geographic region with ­previously naïve host populations.

  14. Detection of Infectious Pancreatic Necrosis Virus from the Leeches Hemiclepsis marginata and Hirudo medicinalis.

    PubMed

    Salimi, Behnam; Abdi, Kazem

    2016-12-01

    Leeches have been reported to harbor several important fish pathogens, including spring viremia of carp virus, infectious hematopoietic necrosis virus (IHNV), and viral hemorrhagic septicemia virus (VHSV), and also may contain blood protozoa. In the present study, leeches were collected from water bodies located in Kurdistan province, Iran. The specimens were tested for IHNV, VHSV, and infectious pancreatic necrosis virus (IPNV) using the PCR method. The results showed that two different species of leeches, Hemiclepsis marginata and Hirudo medicinalis, were infected by IPNV among the seven species studied. The infected leeches were found in areas that were polluted with untreated sewage coming from upstream fish farms culturing Rainbow Trout Oncorhynchus mykiss. In addition, the fish at fish farms in the vicinity had been infected with IPNV 9 months previously. Our results showed that the virus causing infectious pancreatic necrosis is present in the leeches H. marginata and H. medicinalis, suggesting that leeches are a potential source of IPNV in fish farms. Received October 14, 2015; accepted June 1, 2016. PMID:27687675

  15. Companion Animals as a Source of Viruses for Human Beings and Food Production Animals.

    PubMed

    Reperant, L A; Brown, I H; Haenen, O L; de Jong, M D; Osterhaus, A D M E; Papa, A; Rimstad, E; Valarcher, J-F; Kuiken, T

    2016-07-01

    Companion animals comprise a wide variety of species, including dogs, cats, horses, ferrets, guinea pigs, reptiles, birds and ornamental fish, as well as food production animal species, such as domestic pigs, kept as companion animals. Despite their prominent place in human society, little is known about the role of companion animals as sources of viruses for people and food production animals. Therefore, we reviewed the literature for accounts of infections of companion animals by zoonotic viruses and viruses of food production animals, and prioritized these viruses in terms of human health and economic importance. In total, 138 virus species reportedly capable of infecting companion animals were of concern for human and food production animal health: 59 of these viruses were infectious for human beings, 135 were infectious for food production mammals and birds, and 22 were infectious for food production fishes. Viruses of highest concern for human health included hantaviruses, Tahyna virus, rabies virus, West Nile virus, tick-borne encephalitis virus, Crimean-Congo haemorrhagic fever virus, Aichi virus, European bat lyssavirus, hepatitis E virus, cowpox virus, G5 rotavirus, influenza A virus and lymphocytic choriomeningitis virus. Viruses of highest concern for food production mammals and birds included bluetongue virus, African swine fever virus, foot-and-mouth disease virus, lumpy skin disease virus, Rift Valley fever virus, porcine circovirus, classical swine fever virus, equine herpesvirus 9, peste des petits ruminants virus and equine infectious anaemia virus. Viruses of highest concern for food production fishes included cyprinid herpesvirus 3 (koi herpesvirus), viral haemorrhagic septicaemia virus and infectious pancreatic necrosis virus. Of particular concern as sources of zoonotic or food production animal viruses were domestic carnivores, rodents and food production animals kept as companion animals. The current list of viruses provides an objective

  16. Companion Animals as a Source of Viruses for Human Beings and Food Production Animals.

    PubMed

    Reperant, L A; Brown, I H; Haenen, O L; de Jong, M D; Osterhaus, A D M E; Papa, A; Rimstad, E; Valarcher, J-F; Kuiken, T

    2016-07-01

    Companion animals comprise a wide variety of species, including dogs, cats, horses, ferrets, guinea pigs, reptiles, birds and ornamental fish, as well as food production animal species, such as domestic pigs, kept as companion animals. Despite their prominent place in human society, little is known about the role of companion animals as sources of viruses for people and food production animals. Therefore, we reviewed the literature for accounts of infections of companion animals by zoonotic viruses and viruses of food production animals, and prioritized these viruses in terms of human health and economic importance. In total, 138 virus species reportedly capable of infecting companion animals were of concern for human and food production animal health: 59 of these viruses were infectious for human beings, 135 were infectious for food production mammals and birds, and 22 were infectious for food production fishes. Viruses of highest concern for human health included hantaviruses, Tahyna virus, rabies virus, West Nile virus, tick-borne encephalitis virus, Crimean-Congo haemorrhagic fever virus, Aichi virus, European bat lyssavirus, hepatitis E virus, cowpox virus, G5 rotavirus, influenza A virus and lymphocytic choriomeningitis virus. Viruses of highest concern for food production mammals and birds included bluetongue virus, African swine fever virus, foot-and-mouth disease virus, lumpy skin disease virus, Rift Valley fever virus, porcine circovirus, classical swine fever virus, equine herpesvirus 9, peste des petits ruminants virus and equine infectious anaemia virus. Viruses of highest concern for food production fishes included cyprinid herpesvirus 3 (koi herpesvirus), viral haemorrhagic septicaemia virus and infectious pancreatic necrosis virus. Of particular concern as sources of zoonotic or food production animal viruses were domestic carnivores, rodents and food production animals kept as companion animals. The current list of viruses provides an objective

  17. Expression kinetics of key genes in the early innate immune response to Great Lakes viral hemorrhagic septicemia virus IVb infection in yellow perch (Perca flavescens)

    USGS Publications Warehouse

    Olson, Wendy; Emmenegger, Eveline; Glenn, Jolene; Simchick, Crystal; Winton, Jim; Goetz, Frederick

    2013-01-01

    The recently discovered strain of viral hemorrhagic septicemia virus, VHSV-IVb, represents an example of the introduction of an extremely pathogenic rhabdovirus capable of infecting a wide variety of new fish species in a new host-environment. The goal of the present study was to delineate the expression kinetics of key genes in the innate immune response relative to the very early stages of VHSV-IVb infection using the yellow perch (Perca flavescens) as a model. Administration of VHSV-IVb by IP-injection into juvenile yellow perch resulted in 84% cumulative mortality, indicating their high susceptibility to this disease. In fish sampled in the very early stages of infection, a significant up-regulation of Mx gene expression in the liver, as well as IL-1β and SAA activation in the head kidney, spleen, and liver was directly correlated to viral load. The potential down-regulation of Mx in the hematopoietic tissues, head kidney and spleen, may represent a strategy utilized by the virus to increase replication.

  18. Surveillance of Viruses in Wild Fish Populations in Areas around the Gulf of Cadiz (South Atlantic Iberian Peninsula)

    PubMed Central

    Moreno, Patricia; Olveira, José G.; Labella, Alejandro; Cutrín, Juan Manuel; Baro, Jorge C.; Borrego, Juan Jose

    2014-01-01

    This report describes a viral epidemiological study of wild fish around the Gulf of Cadiz (southwestern Iberian Peninsula) and is focused on infectious pancreatic necrosis virus (IPNV), viral hemorrhagic septicemia virus (VHSV), and viral nervous necrosis virus (VNNV). One fish species (Chelon labrosus) was sampled inside the gulf, at the mouth of the San Pedro River. Another 29 were sampled, in three oceanographic campaigns, at sites around the Bay of Cadiz. The fish were processed individually and subjected to isolation in cell culture and molecular diagnosis. VHSV was not isolated from any species. Thirteen IPNV-type isolates were obtained from barracuda (Sphyraena sphyraena), axillary seabream (Pagellus acarne), common two-banded seabream (Diplodus vulgaris), common pandora (P. erythrinus), Senegal seabream (D. bellottii), and surmullet (Mullus surmuletus). Six VNNV isolates were obtained from axillary seabream, common pandora, black seabream (Spondyliosoma cantharus), red mullet (Mullet barbatus), Lusitanian toadfish (Halobatrachus didactylus), and tub gurnard (Chelidonichtys lucerna). In the river mouth, viruses were detected only after reamplification, obtaining prevalence percentages of IPNV and VNNV (44.4 and 63.0%, respectively) much higher than those observed in the oceanographic campaigns (25.7 and 19.6%, respectively). The opposite results were obtained in the case of VHSV after reamplification: 11.1% in the river mouth and 43.6% in the oceanic locations. Analyzing the results with respect to the proximity of the sampling sites to the coast, an anthropogenic influence on wild fish is suggested and discussed. The type of viruses and the presence of natural reassortants are also discussed. PMID:25128341

  19. Phylogeny of the Viral Hemorrhagic Septicemia Virus in European Aquaculture

    PubMed Central

    Cieslak, Michael; Mikkelsen, Susie S.; Skall, Helle F.; Baud, Marine; Diserens, Nicolas; Engelsma, Marc Y.; Haenen, Olga L. M.; Mousakhani, Shirin; Panzarin, Valentina; Wahli, Thomas; Olesen, Niels J.; Schütze, Heike

    2016-01-01

    One of the most valuable aquaculture fish in Europe is the rainbow trout, Oncorhynchus mykiss, but the profitability of trout production is threatened by a highly lethal infectious disease, viral hemorrhagic septicemia (VHS), caused by the VHS virus (VHSV). For the past few decades, the subgenogroup Ia of VHSV has been the main cause of VHS outbreaks in European freshwater-farmed rainbow trout. Little is currently known, however, about the phylogenetic radiation of this Ia lineage into subordinate Ia clades and their subsequent geographical spread routes. We investigated this topic using the largest Ia-isolate dataset ever compiled, comprising 651 complete G gene sequences: 209 GenBank Ia isolates and 442 Ia isolates from this study. The sequences come from 11 European countries and cover the period 1971–2015. Based on this dataset, we documented the extensive spread of the Ia population and the strong mixing of Ia isolates, assumed to be the result of the Europe-wide trout trade. For example, the Ia lineage underwent a radiation into nine Ia clades, most of which are difficult to allocate to a specific geographic distribution. Furthermore, we found indications for two rapid, large-scale population growth events, and identified three polytomies among the Ia clades, both of which possibly indicate a rapid radiation. However, only about 4% of Ia haplotypes (out of 398) occur in more than one European country. This apparently conflicting finding regarding the Europe-wide spread and mixing of Ia isolates can be explained by the high mutation rate of VHSV. Accordingly, the mean period of occurrence of a single Ia haplotype was less than a full year, and we found a substitution rate of up to 7.813 × 10−4 nucleotides per site per year. Finally, we documented significant differences between Germany and Denmark regarding their VHS epidemiology, apparently due to those countries’ individual handling of VHS. PMID:27760205

  20. Rapid identification of Pasteurella multocida organisms responsible for haemorrhagic septicaemia using an enzyme-linked immunosorbent assay.

    PubMed

    Dawkins, H J; Johnson, R B; Spencer, T L; Patten, B E

    1990-11-01

    Haemorrhagic septicaemia (HS) is caused by specific serotypes of Pasteurella multocida and is one of the major economic diseases of cattle and buffalo in South East Asia. Definitive diagnosis of the disease-causing organism with the available methods is labour intensive and not totally reliable, consequently, an ELISA system to identify P multocida organisms which cause HS was developed. One hundred and twenty-four P multocida isolates were tested, 58 were type strains and 66 were field isolates. Analysis of these strains indicated the assay had a specificity of 99 per cent and sensitivity of at least 86 per cent. The sensitivity could be an underestimate, as five isolates assumed to be false negative reactions may not all be HS-causing strains. The HS ELISA provides a rapid, simple, accurate and inexpensive diagnostic assay for identification of HS causing organisms but does not represent a new typing system for P multocida. This assay will also enable countries to assess the impact of HS more accurately.

  1. Corexit 9500 Inactivates Two Enveloped Viruses of Aquatic Animals but Enhances the Infectivity of a Nonenveloped Fish Virus

    PubMed Central

    Pham, P. H.; Huang, Y. J.; Chen, C.

    2014-01-01

    The effects of Corexit 9500, a dispersant used to clean up oil spills, on invertebrates, lower vertebrates, birds, and human health have been examined, but there is a significant lack of study of the effect of this dispersant on aquatic viruses. In this study, the effects of Corexit 9500 on four aquatic viruses of differing structural composition were examined. Corexit 9500 reduced the titer of the enveloped viral hemorrhagic septicemia virus (VHSV) at all concentrations (10% to 0.001%) examined. The titer of frog virus 3 (FV3), a virus with both enveloped and nonenveloped virions, was reduced only at the high Corexit 9500 concentrations (10% to 0.1%). Corexit 9500 was unable to reduce the titer of nonenveloped infectious pancreatic necrosis virus (IPNV) but enhanced the titer of chum salmon reovirus (CSV) by 2 to 4 logs. With the ability to inactivate enveloped viruses and possibly enhance some nonenveloped viruses, Corexit 9500 has the potential to alter the aquatic virosphere. PMID:24271186

  2. Child Mortality after Discharge from a Health Facility following Suspected Pneumonia, Meningitis or Septicaemia in Rural Gambia: A Cohort Study

    PubMed Central

    Chhibber, Aakash Varun; Hill, Philip C.; Jafali, James; Jasseh, Momodou; Hossain, Mohammad Ilias; Ndiaye, Malick; Pathirana, Jayani C.; Greenwood, Brian; Mackenzie, Grant A.

    2015-01-01

    Objective To measure mortality and its risk factors among children discharged from a health centre in rural Gambia. Methods We conducted a cohort study between 12 May 2008 and 11 May 2012. Children aged 2–59 months, admitted with suspected pneumonia, sepsis, or meningitis after presenting to primary and secondary care facilities, were followed for 180 days after discharge. We developed models associating post-discharge mortality with clinical syndrome on admission and clinical risk factors. Findings One hundred and five of 3755 (2.8%) children died, 80% within 3 months of discharge. Among children aged 2–11 and 12–59 months, there were 30 and 29 deaths per 1000 children per 180 days respectively, compared to 11 and 5 respectively in the resident population. Children with suspected pneumonia unaccompanied by clinically severe malnutrition (CSM) had the lowest risk of post-discharge mortality. Mortality increased in children with suspected meningitis or septicaemia without CSM (hazard ratio [HR] 2.6 and 2.2 respectively). The risk of mortality greatly increased with CSM on admission: CSM with suspected pneumonia (HR 8.1; 95% confidence interval (CI) 4.4 to 15), suspected sepsis (HR 18.4; 95% CI 11.3 to 30), or suspected meningitis (HR 13.7; 95% CI 4.2 to 45). Independent associations with mortality were: mid-upper arm circumference (MUAC) of 11.5–13.0 cm compared to >13.0 cm (HR 7.2; 95% CI 3.0 to 17.0), MUAC 10.5–11.4 cm (HR 24; 95% CI 9.4 to 62), and MUAC <10.5 cm (HR 44; 95% CI 18 to 108), neck stiffness (HR 10.4; 95% CI 3.1 to 34.8), non-medical discharge (HR 4.7; 95% CI 2.0 to 10.9), dry season discharge (HR 2.0; 95% CI 1.2 to 3.3), while greater haemoglobin (HR 0.82; 0.73 to 0.91), axillary temperature (HR 0.71; 95% CI 0.58 to 0.87), and oxygen saturation (HR 0.96; 95% CI 0.93 to 0.99) were associated with reduced mortality. Conclusion Gambian children experience increased mortality after discharge from primary and secondary care. Interventions should

  3. Viral hemorrhagic septicemia virus, Ichthyophonus hoferi, and other causes of morbidity in Pacific herring Clupea pallasi spawning in Prince William Sound, Alaska, USA.

    PubMed

    Marty, G D; Freiberg, E F; Meyers, T R; Wilcock, J; Farver, T B; Hinton, D E

    1998-02-26

    Pacific herring Clupea pallasi populations in Prince William Sound, Alaska, USA, declined from an estimated 9.8 x 10(7) kg in 1992 to 1.5 x 10(7) kg in 1994. To determine the role of disease in population decline, 233 Pacific herring from Prince William Sound were subjected to complete necropsy during April 1994. The North American strain of viral hemorrhagic septicemia virus (VHSV) was isolated from 11 of 233 fish (4.7%). VHSV was significantly related to myocardial mineralization, hepatocellular necrosis, submucosal gastritis, and meningoencephalitis. Ichthyophonus hoferi infected 62 of 212 (29%) fish. I. hoferi infections were associated with severe, disseminated, granulomatous inflammation and with increased levels of plasma creatine phosphokinase (CPK) and aspartate aminotransferase (AST). I. hoferi prevalence in 1994 was more than double that of most previous years (1989 to 1993). Plasma chemistry values significantly greater (p < 0.01) in males than females included albumin, total protein, cholesterol, chloride, glucose, and potassium; only alkaline phosphatase was significantly greater in females. Hypoalbuminemia was relatively common in postspawning females; other risk factors included VHSV and moderate or severe focal skin reddening. Pacific herring had more than 10 species of parasites, but they were not associated with significant lesions. Two of the parasites have not previously been described: a renal intraductal myxosporean (11% prevalence) and an intestinal coccidian (91% prevalence). Transmission electron microscopy of a solitary mesenteric lesion revealed viral particles consistent with lymphocystis virus. No fish had viral erythrocytic necrosis (VEN). Prevalence of external gross lesions and major parasites was not related to fish age, and fish that were year-lings at the time of the 1989 'Exxon Valdez' oil spill (1988 year class) had no evidence of increased disease prevalence. PMID:9676259

  4. Development of a multiplex assay to measure the effects of shipping and storage conditions on the quality of RNA used in molecular assays for detection of viral haemorrhagic septicemia virus.

    PubMed

    Siah, A; Duesund, H; Frisch, K; Nylund, A; McKenzie, P; Saksida, S

    2014-09-01

    Abstract In routine diagnostics, real-time reverse transcriptase quantitative PCR (RT-qPCR) has become a powerful method for fish health screening. Collection, transportation, and storage conditions of specimens could dramatically affect their integrity and could consequently affect RT-qPCR test results. In this study, to assess the expression profile of elongation factor 1 alpha (ELF-1α) gene, head kidney (HK) tissues from Atlantic Salmon Salmo salar were exposed at room temperature, 4°C, -20°C, and -80°C as well as in 70% ethanol for 6, 12, 24, 48, and 72 h. Data showed a significant increase of RT-qPCR cycle threshold (Ct) values for ELF-1α ranging from 14.7 to 26.5 cycles for tissues exposed to room temperature. In order to mimic the sample transportation conditions, different temperatures of storage were used and tissue quality was evaluated using ELF-1α gene expression. Data showed that Ct values for ELF-1α increased significantly when the tissues were transported on ice for 2 h, stored at -20°C, thawed on ice for 6 h, and stored again at -80°C. The HK tissues collected from Atlantic Salmon challenged with viral hemorrhagic septicemia virus (VHSV) through intraperitoneal injection were exposed at room temperature for 0, 6, 12, 24, 48, 72, and 96 h. Data showed a good correlation of values for ELF-1α and VHSV Ct although the ELF-1α mRNA of the host degraded faster than the RNA of VHSV. Based on these data, HK tissues could be transported on ice or ice packs without the quality of the tissue being affected when stored at -80°C upon arrival at the laboratory. In addition, 70% ethanol could be used as a preservative for long-distance transportation. For an efficient diagnostic test, a duplex VHSV-ELF-1α was developed and optimized. Data showed that the sensitivity of the duplex assay for VHSV was similar to the singleplex. Received November 25, 2013; accepted February 14, 2014. PMID:25229489

  5. The glycoprotein genes and gene junctions of the fish rhabdoviruses spring viremia of carp virus and hirame rhabdovirus: Analysis of relationships with other rhabdoviruses

    USGS Publications Warehouse

    Bjorklund, H.V.; Higman, K.H.; Kurath, G.

    1996-01-01

    The nucleotide sequences of the glycoprotein genes and all of the internal gene junctions of the fish pathogenic rhabdoviruses spring viremia of carp virus (SVCV) and hirame rhabdovirus (HIRRV) have been determined from cDNA clones generated from viral genomic RNA. The SVCV glycoprotein gene sequence is 1588 nucleotides (nt) long and encodes a 509 amino acid (aa) protein. The HIRRV glycoprotein gene sequence comprises 1612 nt, coding for a 508 aa protein. In sequence comparisons of 15 rhabdovirus glycoproteins, the SVCV glycoprotein gene showed the highest amino acid sequence identity (31.2-33.2%) with vesicular stomatitis New Jersey virus (VSNJV), Chandipura virus (CHPV) and vesicular stomatitis Indiana virus (VSIV). The HIRRV glycoprotein gene showed a very high amino acid sequence identity (74.3%) with the glycoprotein gene of another fish pathogenic rhabdovirus, infectious hematopoietic necrosis virus (IHNV), but no significant similarity with glycoproteins of VSIV or rabies virus (RABV). In phylogenetic analyses SVCV was grouped consistently with VSIV, VSNJV and CHPV in the Vesiculovirus genus of Rhabdoviridae. The fish rhabdoviruses HIRRV, IHNV and viral hemorrhagic septicemia virus (VHSV) showed close relationships with each other, but only very distant relationships with mammalian rhabdoviruses. The gene junctions are highly conserved between SVCV and VSIV, well conserved between IHNV and HIRRV, but not conserved between HIRRV/IHNV and RABV. Based on the combined results we suggest that the fish lyssa-type rhabdoviruses HIRRV, IHNV and VHSV may be grouped in their own genus within the family Rhabdoviridae. Aquarhabdovirus has been proposed for the name of this new genus.

  6. Characterization and applications of a monoclonal antibody against infectious salmon anaemia virus.

    PubMed

    Falk, K; Namork, E; Dannevig, B H

    1998-10-01

    The preparation of the first monoclonal antibody (MAb) against the orthomyxovirus-like infectious salmon anaemia (ISA) virus is described. Characterization of the MAb included isotyping, enzyme-linked immunosorbent assay (ELISA), immunofluorescent staining of virus infected cell cultures (SHK-1 cells), immunoelectron microscopy (IEM) of negatively stained virus preparations, virus neutralization assay and haemagglutination inhibition assay. The MAb reacted with ISA virus preparations both with immunofluorescent staining and in ELISA. No reactions were observed in cell cultures infected with other viruses infecting salmonids including infectious pancreatic necrosis (IPN) virus, viral haemorrhagic septicaemia (VHS) virus and infectious haematopoietic necrosis (IHN) virus. The MAb was also shown to neutralize ISA virus infection in cell cultures and to inhibit the haemagglutination reaction. IEM demonstrated binding to the surface of negatively stained ISA virions. Thus, it is concluded that the MAb binds to the haemagglutinin on the virion surface. Furthermore, using immunofluorescent staining of virus infected cell cultures, reactivity against all the 13 ISA virus strains currently available was demonstrated. Using the MAb, a simple, rapid direct immunofluorescent assay for ISA virus detection and titration in 96-well tissue culture plates was developed. Infectivity titrations by this method correlated well with titration by cytopathic effects. The reliability of the assay was demonstrated by close agreement in virus infectivity titres among different assays for the same virus that were performed on the same day and on different days. A method for detection of viral antigen in cryosections from ISA diseased fish is also reported that may prove useful for the diagnosis and control of ISA.

  7. Overview of recent DNA vaccine development for fish

    USGS Publications Warehouse

    Kurath, G.; ,

    2005-01-01

    Since the first description of DNA vaccines for fish in 1996, numerous studies of genetic immunisation against the rhabdovirus pathogens infectious haematopoietic necrosis virus (IHNV) and viral haemorrhagic septicaemia virus (VHSV) have established their potential as both highly efficacious biologicals and useful basic research tools. Single small doses of rhabdovirus DNA constructs provide extremely strong protection against severe viral challenge under a variety of conditions. DNA vaccines for several other important fish viruses, bacteria, and parasites are under investigation, but they have not yet shown high efficacy. Therefore, current research is focussed on mechanistic studies to understand the basis of protection, and on improvement of the nucleic acid vaccine applications against a wider range of fish pathogens.

  8. Improving the safety of viral DNA vaccines: development of vectors containing both 5' and 3' homologous regulatory sequences from non-viral origin.

    PubMed

    Martinez-Lopez, A; Encinas, P; García-Valtanen, P; Gomez-Casado, E; Coll, J M; Estepa, A

    2013-04-01

    Although some DNA vaccines have proved to be very efficient in field trials, their authorisation still remains limited to a few countries. This is in part due to safety issues because most of them contain viral regulatory sequences to driving the expression of the encoded antigen. This is the case of the only DNA vaccine against a fish rhabdovirus (a negative ssRNA virus), authorised in Canada, despite the important economic losses that these viruses cause to aquaculture all over the world. In an attempt to solve this problem and using as a model a non-authorised, but efficient DNA vaccine against the fish rhabdovirus, viral haemorrhagic septicaemia virus (VHSV), we developed a plasmid construction containing regulatory sequences exclusively from fish origin. The result was an "all-fish vector", named pJAC-G, containing 5' and 3' regulatory sequences of β-acting genes from carp and zebrafish, respectively. In vitro and in vivo, pJAC-G drove a successful expression of the VHSV glycoprotein G (G), the only antigen of the virus conferring in vivo protection. Furthermore, and by means of in vitro fusion assays, it was confirmed that G protein expressed from pJAC-G was fully functional. Altogether, these results suggest that DNA vaccines containing host-homologous gene regulatory sequences might be useful for developing safer DNA vaccines, while they also might be useful for basic studies.

  9. Effect of alum co-adjuvantation of oil adjuvant vaccine on emulsion stability and immune responses against haemorhagic septicaemia in mice

    PubMed Central

    Kumar, Sujeet; Chaturvedi, Vinod Kumar; Kumar, Bablu; Kumar, Pankaj; Somarajan, Sudha Rani; Mishra, Anil Kumar; Sharma, Bhaskar

    2015-01-01

    Background and Objectives: Haemorrhagic septicaemia (HS), caused by Pasteurella multocida, is the most important bacterial disease of cattle and buffaloes in India. Oil adjuvant vaccine (OAV) is the most potent vaccine available for the control of HS. The study aims to evaluate the effect of alum co-adjuvantation of OAV on emulsion stability and immune response. Materials and Methods: Two different oil adjuvant vaccines viz., standard oil adjuvant vaccine (OAV) and alum precipitated oil adjuvant vaccine (A–OAV) were prepared with Pasteurella multocida antigen. Emulsion stability was tested by centrifugation, storage at 37 °C for 3 months and microscopy. Immune responses were evaluated by ELISA antibody titer, CD4, CD8 T cell populations and survival post challenge by P. multocida in mice. Results: The separation of aqueous and oil phase of emulsion by centrifugation and storage test were 0 and 6.76% in A-OAV as compared to 11.00 and 26.39% in OAV, respectively. The mean droplet size was significantly smaller (p<0.01) in A–OAV as compared to OAV. The A–OAV recorded higher ELISA antibody titer (p<0.05) up to 21st days post vaccination, and higher CD4 (p>0.05) and CD8 T cell (p<0.05) populations compared to OAV. The A–OAV group conferred 100% protection after challenge with both 100 LD50 and 1000 LD50 as compared to 100 and 60% respective protection by OAV group. Conclusion: The results indicates that A–OAV had better emulsion stability, produces higher level of CD4, CD8 T cells and antibody titer with better protection compared to oil adjuvant vaccine. PMID:26622968

  10. The North American strain of viral hemorrhagic septicemia virus is highly pathogenic for laboratory-reared Pacific herring (Clupea pallasi)

    USGS Publications Warehouse

    Kocan, R.; Bradley, M.; Elder, N.; Meyers, T.; Batts, W.; Winton, J.

    1997-01-01

    Specific-pathogen-free Pacific herring Clupea pallasi were reared in the laboratory from eggs and then challenged at 5, 9, and 13 months of age by waterborne exposure to low (101.5–2.5 plaque-forming units [PFU] per milliliter), medium (103.5–4.5 PFU/mL), or high (105.5–6.5 PFU/mL) levels of a North American isolate of viral hemorrhagic septicemia virus (VHSV). The fish were extremely susceptible to the virus, showing clinical disease, mortality approaching 100%, and only a limited increase in resistance with age. Mortality began 4–6 d after exposure and peaked at approximately day 7 in fish exposed to high levels of virus. Whereas the mean time to death showed a significant dose response (P < 0.001), the percent mortality and virus titers in dead fish were generally high in all groups regardless of initial challenge dose. External signs of disease were usually limited to 1–2-mm hemorrhagic areas on the lower jaw and isthmus and around the eye, but 2 of 130 infected fish exhibited extensive cutaneous hemorrhaging. Histopathologic examination of tissues from moribund fish sampled at 2–8 d after exposure revealed multifocal coagulative necrosis of hepatocytes, diffuse necrosis of interstitial hematopoietic tissues in the kidney, diffuse necrosis of the spleen, epidermis, and subcutis, and occasional necrosis of pancreatic acinar cells. Virus titers in tissues of experimentally infected herring were first detected 48 h after exposure and peaked 6-8 d after exposure at 107.7 PFU/g. Fish began shedding virus at 48 h after exposure with titers in the flow-through aquaria reaching 102.5 PFU/mL at 4–5 d after exposure, just before peak mortality. When the water flow was turned off for 3 h, titers in the water rose to 103.5 PFU/mL, and the amount of virus shed by infected fish (on average, greater than 106.5 PFU/h per fish) appeared sufficient to sustain a natural epizootic among schooling herring. Taken together, these data suggest that VHSV could be a

  11. Ammocoetes of Pacific lamprey are not susceptible to common fish rhabdoviruses of the U.S. Pacific Northwest

    USGS Publications Warehouse

    Kurath, Gael; Jolley, C J.; Thompson, Tarin M.; Thompson, D.; Whitesel, A.T.; Gutenberger, S.; Winton, James R.

    2013-01-01

    Pacific Lampreys Entosphenus tridentatus have experienced severe population declines in recent years and efforts to develop captive rearing programs are under consideration. However, there is limited knowledge of their life history, ecology, and potential to harbor or transmit pathogens that may cause infectious disease. As a measure of the possible risks associated with introducing wild lampreys into existing fish culture facilities, larval lampreys (ammocoetes) were tested for susceptibility to infection and mortality caused by experimental exposures to the fish rhabdovirus pathogens: infectious hematopoietic necrosis virus (IHNV) and viral haemorrhagic septicaemia virus (VHSV). Two IHNV isolates, representing the U and M genogroups, and one VHSV isolate from the IVa genotype were each delivered to groups of ammocoetes by immersion at moderate and high viral doses, and by intraperitoneal injection. Ammocoetes were then held in triplicate tanks with no substrate or sediment. During 41 d of observation postchallenge there was low or no mortality in all groups, and no virus was detected in the small number of fish that died. Ammocoetes sampled for incidence of infection at 6 and 12 d after immersion challenges also had no detectable virus, and no virus was detected in surviving fish from any group. A small number of ammocoetes sampled 6 d after the injection challenge had detectable virus, but at levels below the original quantity of virus injected. Overall there was no evidence of infection, replication, or persistence of any of the viruses in any of the treatment groups. Our results suggest that Pacific Lampreys are highly unlikely to serve as hosts that maintain or transmit these viruses.

  12. Ammocoetes of Pacific Lamprey are not susceptible to common fish rhabdoviruses of the U.S. Pacific northwest.

    PubMed

    Kurath, G; Jolley, J C; Thompson, T M; Thompson, D; Whitesel, T A; Gutenberger, S; Winton, J R

    2013-12-01

    Pacific Lampreys Entosphenus tridentatus have experienced severe population declines in recent years and efforts to develop captive rearing programs are under consideration. However, there is limited knowledge of their life history, ecology, and potential to harbor or transmit pathogens that may cause infectious disease. As a measure of the possible risks associated with introducing wild lampreys into existing fish culture facilities, larval lampreys (ammocoetes) were tested for susceptibility to infection and mortality caused by experimental exposures to the fish rhabdovirus pathogens: infectious hematopoietic necrosis virus (IHNV) and viral haemorrhagic septicaemia virus (VHSV). Two IHNV isolates, representing the U and M genogroups, and one VHSV isolate from the IVa genotype were each delivered to groups of ammocoetes by immersion at moderate and high viral doses, and by intraperitoneal injection. Ammocoetes were then held in triplicate tanks with no substrate or sediment. During 41 d of observation postchallenge there was low or no mortality in all groups, and no virus was detected in the small number of fish that died. Ammocoetes sampled for incidence of infection at 6 and 12 d after immersion challenges also had no detectable virus, and no virus was detected in surviving fish from any group. A small number of ammocoetes sampled 6 d after the injection challenge had detectable virus, but at levels below the original quantity of virus injected. Overall there was no evidence of infection, replication, or persistence of any of the viruses in any of the treatment groups. Our results suggest that Pacific Lampreys are highly unlikely to serve as hosts that maintain or transmit these viruses.

  13. Inventing Viruses.

    PubMed

    Summers, William C

    2014-11-01

    In the nineteenth century, "virus" commonly meant an agent (usually unknown) that caused disease in inoculation experiments. By the 1890s, however, some disease-causing agents were found to pass through filters that retained the common bacteria. Such an agent was called "filterable virus," the best known being the virus that caused tobacco mosaic disease. By the 1920s there were many examples of filterable viruses, but no clear understanding of their nature. However, by the 1930s, the term "filterable virus" was being abandoned in favor of simply "virus," meaning an agent other than bacteria. Visualization of viruses by the electron microscope in the late 1930s finally settled their particulate nature. This article describes the ever-changing concept of "virus" and how virologists talked about viruses. These changes reflected their invention and reinvention of the concept of a virus as it was revised in light of new knowledge, new scientific values and interests, and new hegemonic technologies.

  14. Inventing Viruses.

    PubMed

    Summers, William C

    2014-11-01

    In the nineteenth century, "virus" commonly meant an agent (usually unknown) that caused disease in inoculation experiments. By the 1890s, however, some disease-causing agents were found to pass through filters that retained the common bacteria. Such an agent was called "filterable virus," the best known being the virus that caused tobacco mosaic disease. By the 1920s there were many examples of filterable viruses, but no clear understanding of their nature. However, by the 1930s, the term "filterable virus" was being abandoned in favor of simply "virus," meaning an agent other than bacteria. Visualization of viruses by the electron microscope in the late 1930s finally settled their particulate nature. This article describes the ever-changing concept of "virus" and how virologists talked about viruses. These changes reflected their invention and reinvention of the concept of a virus as it was revised in light of new knowledge, new scientific values and interests, and new hegemonic technologies. PMID:26958713

  15. Zika Virus

    MedlinePlus

    Zika is a virus that is spread mostly by mosquitoes. A pregnant mother can pass it to ... through blood transfusions. There have been outbreaks of Zika virus in the United States, Africa, Southeast Asia, ...

  16. Zika Virus

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Zika Virus Note: Javascript is disabled or is not supported ... Areas with Zika Countries and territories with active Zika virus transmission... Mosquito Control Prevent mosquito bites, integrated mosquito ...

  17. Chikungunya Virus

    MedlinePlus

    ... traveling to countries with chikungunya virus, use insect repellent, wear long sleeves and pants, and stay in ... Chikungunya Prevention is key! Prevent Infection. Use mosquito repellent. Chikungunya Virus Distribution Chikungunya in the U.S. What's ...

  18. Virus Maturation

    PubMed Central

    Veesler, David; Johnson, John E.

    2013-01-01

    We examined virus maturation of selected non-enveloped and enveloped ssRNA viruses; retroviruses; bacteriophages and herpes virus. Processes associated with maturation in the RNA viruses range from subtle (noda and picornaviruses) to dramatic (tetraviruses and togaviruses). The elaborate assembly and maturation pathway of HIV is discussed in contrast to the less sophisticated but highly efficient processes associated with togaviruses. Bacteriophage assembly and maturation are discussed in general terms with specific examples chosen for emphasis. Finally the herpes viruses are compared with bacteriophages. The data support divergent evolution of noda, picorna and tetraviruses from a common ancestor and divergent evolution of alpha and flaviviruses from a common ancestor. Likewise, bacteriophages and herpes viruses almost certainly share a common ancestor in their evolution. Comparing all the viruses, we conclude that maturation is a convergent process that is required to solve conflicting requirements in biological dynamics and function. PMID:22404678

  19. Zika virus.

    PubMed

    2016-02-10

    Essential facts Zika virus disease is caused by a virus that is transmitted by the Aedes mosquito. While it generally causes a mild illness, there is increasing concern that it is harmful in pregnancy and can cause congenital abnormalities in infants born to women infected with the virus. There is no antiviral treatment or vaccine currently available. The best form of prevention is protection against mosquito bites.

  20. Ebola virus.

    PubMed

    Streether, L A

    1999-01-01

    Ebola virus was first identified as a filovirus in 1976, following epidemics of severe haemorrhagic fever in sub-Saharan Africa. Further outbreaks have occurred since, but, despite extensive and continued investigations, the natural reservoir for the virus remains unknown. The mortality rate is high and there is no cure for Ebola virus infection. Molecular technology is proving useful in extending our knowledge of the virus. Identification of the host reservoir, control and prevention of further outbreaks, rapid diagnosis of infection, and vaccine development remain areas of continued interest in the fight against this biosafety level-four pathogen.

  1. Virus Crystallography

    NASA Astrophysics Data System (ADS)

    Fry, Elizabeth; Logan, Derek; Stuart, David

    Crystallography provides a means of visualizing intact virus particles as well as their isolated constituent proteins and enzymes (1-3) at near-atomic resolution, and is thus an extraordinarily powerful tool in the pursuit of a fuller understanding of the functioning of these simple biological systems. We have already expanded our knowledge of virus evolution, assembly, antigenic variation, and host-cell interactions; further studies will no doubt reveal much more. Although the rewards are enormous, an intact virus structure determination is not a trivial undertaking and entails a significant scaling up in terms of time and resources through all stages of data collection and processing compared to a traditional protein crystallographic structure determination. It is the methodology required for such studies that will be the focus of this chapter. The computational requirements were satisfied in the late 1970s, and when combined with the introduction of phase improvement techniques utilizing the virus symmetry (4,5), the application of crystallography to these massive macromolecular assemblies became feasible. This led to the determination of the first virus structure (the small RNA plant virus, tomato bushy stunt virus), by Harrison and coworkers in 1978 (6). The structures of two other plant viruses followed rapidly (7,8). In the 1980s, a major focus of attention was a family of animal RNA viruses; the Picornaviridae.

  2. Live Virus Smallpox Vaccine

    MedlinePlus

    ... Index SMALLPOX FACT SHEET The Live Virus Smallpox Vaccine The vaccinia virus is the "live virus" used ... cannot cause smallpox. What is a "live virus" vaccine? A "live virus" vaccine is a vaccine that ...

  3. Quantitative expression profiling of immune response genes in rainbow trout following infectious haematopoietic necrosis virus (IHNV) infection or DNA vaccination

    USGS Publications Warehouse

    Purcell, Maureen K.; Kurath, Gael; Garver, Kyle A.; Herwig, Russell P.; Winton, James R.

    2004-01-01

    Infectious haematopoietic necrosis virus (IHNV) is a well-studied virus of salmonid fishes. A highly efficacious DNA vaccine has been developed against this virus and studies have demonstrated that this vaccine induces both an early and transient non-specific anti-viral phase as well as long-term specific protection. The mechanisms of the early anti-viral phase are not known, but previous studies noted changes in Mx gene expression, suggesting a role for type I interferon. This study used quantitative real-time reverse transcriptase PCR methodology to compare expression changes over time of a number of cytokine or cytokine-related genes in the spleen of rainbow trout following injection with poly I:C, live IHNV, the IHNV DNA vaccine or a control plasmid encoding the non-antigenic luciferase gene. The target genes included Mx-1, viral haemorrhagic septicaemia virus induced gene 8 (Vig-8), TNF-α1, TNF-α2, IL-1β1, IL-8, TGF-β1 and Hsp70. Poly I:C stimulation induced several genes but the strongest and significant response was observed in the Mx-1 and Vig-8 genes. The live IHN virus induced a significant response in all genes examined except TGF-β1. The control plasmid construct and the IHNV DNA vaccine marginally induced a number of genes, but the main difference between these two groups was a statistically significant induction of the Mx-1 and Vig-8 genes by the IHNV vaccine only. The gene expression profiles elicited by the live virus and the IHNV DNA vaccine differed in a number of aspects but this study confirms the clear role for a type I interferon-like response in early anti-viral defence.

  4. Computer viruses

    NASA Technical Reports Server (NTRS)

    Denning, Peter J.

    1988-01-01

    The worm, Trojan horse, bacterium, and virus are destructive programs that attack information stored in a computer's memory. Virus programs, which propagate by incorporating copies of themselves into other programs, are a growing menace in the late-1980s world of unprotected, networked workstations and personal computers. Limited immunity is offered by memory protection hardware, digitally authenticated object programs,and antibody programs that kill specific viruses. Additional immunity can be gained from the practice of digital hygiene, primarily the refusal to use software from untrusted sources. Full immunity requires attention in a social dimension, the accountability of programmers.

  5. Hendra virus.

    PubMed

    Middleton, Deborah

    2014-12-01

    Hendra virus infection of horses occurred sporadically between 1994 and 2010 as a result of spill-over from the viral reservoir in Australian mainland flying-foxes, and occasional onward transmission to people also followed from exposure to affected horses. An unprecedented number of outbreaks were recorded in 2011 leading to heightened community concern. Release of an inactivated subunit vaccine for horses against Hendra virus represents the first commercially available product that is focused on mitigating the impact of a Biosafety Level 4 pathogen. Through preventing the development of acute Hendra virus disease in horses, vaccine use is also expected to reduce the risk of transmission of infection to people.

  6. Hendra virus.

    PubMed

    Middleton, Deborah

    2014-12-01

    Hendra virus infection of horses occurred sporadically between 1994 and 2010 as a result of spill-over from the viral reservoir in Australian mainland flying-foxes, and occasional onward transmission to people also followed from exposure to affected horses. An unprecedented number of outbreaks were recorded in 2011 leading to heightened community concern. Release of an inactivated subunit vaccine for horses against Hendra virus represents the first commercially available product that is focused on mitigating the impact of a Biosafety Level 4 pathogen. Through preventing the development of acute Hendra virus disease in horses, vaccine use is also expected to reduce the risk of transmission of infection to people. PMID:25281398

  7. Differential response of the Senegalese sole (Solea senegalensis) Mx promoter to viral infections in two salmonid cell lines.

    PubMed

    Alvarez-Torres, Daniel; Alonso, M Carmen; Garcia-Rosado, Esther; Collet, Bertrand; Béjar, Julia

    2014-10-15

    Mx proteins are main effectors of the antiviral innate immune defence mediated by type I interferon (IFN I). The IFN I response is under a complex regulation; hence, one of the key issues in understanding virus-host interaction is the knowledge of the regulatory mechanisms governing this response. With this purpose, in this study Chinook salmon embryo cells (CHSE-214) and rainbow trout gonad cells (RTG-2) were transiently transfected with a vector containing the luciferase reporter gene under the control of the Senegalese sole Mx promoter. These transfected cells were infected with infectious pancreatic necrosis virus (IPNV), viral haemorrhagic septicaemia virus (VHSV) and epizootic haematopoietic necrosis virus (EHNV) at different doses in order to study the luciferase fold induction in response to viral infections. Transfected CHSE-214 cells infected with EHNV showed significant induction of the luciferase reporter gene, compared to control non-infected cells, at different times post infection (p.i.). The maximum expression was recorded at 24h p.i. in cells inoculated with 5 × 10(2)TCID50/mL (2.17 folds compared to control cells). In these cells, the infection with IPNV and VHSV did not result in the luciferase expression at any time and doses tested. In transfected RTG-2 cells, VHSV stimulated luciferase expression, obtaining a maximum activity at 48 h p.i. in cells infected with 5 × 10(2)TCID50/mL (2.9 folds compared to control cells), whereas RTG-2 cells infected with IPNV and EHNV did not show significant luciferase activity at any time point. The different induction of the Senegalese sole Mx promoter in CHSE-214 and RTG-2 cells after infection with the same viruses indicates that cell-specific factors are significantly involved in the IFN-signalling response, and, probably, on the success of the strategies of these viruses to escape the IFN mechanisms. The use of these two different cellular systems might be an interesting approach to identify such

  8. Zika Virus

    MedlinePlus

    ... be at risk for developing fetal complications. Blood, organ and tissue donor screening tests are also needed to assure the safety of transfusion and transplantation in areas of active mosquito-borne virus transmission. ...

  9. Chikungunya virus

    MedlinePlus

    ... first time in the Americas in the Caribbean Islands. In the Americas, local transmission of the disease ... in Florida, Puerto Rico, and the U.S. Virgin Islands. How Chikungunya can spread Mosquitoes spread the virus ...

  10. Zika Virus.

    PubMed

    Phillips, Jennan A; Neyland, Anavernyel

    2016-08-01

    Zika virus (ZIKV) infections are the latest global public health emergency. Occupational health nurses can protect society by educating workers, women of childbearing age, and others traveling in ZIKV-infected areas about prevention strategies.

  11. Dengue virus.

    PubMed

    Ross, Ted M

    2010-03-01

    Dengue is the most prevalent arthropod-borne virus affecting humans today. The virus group consists of 4 serotypes that manifest with similar symptoms. Dengue causes a spectrum of disease, ranging from a mild febrile illness to a life-threatening dengue hemorrhagic fever. Breeding sites for the mosquitoes that transmit dengue virus have proliferated, partly because of population growth and uncontrolled urbanization in tropical and subtropical countries. Successful vector control programs have also been eliminated, often because of lack of governmental funding. Dengue viruses have evolved rapidly as they have spread worldwide, and genotypes associated with increased virulence have spread across Asia and the Americas. This article describes the virology, epidemiology, clinical manifestations and outcomes, and treatments/vaccines associated with dengue infection.

  12. Zika Virus.

    PubMed

    Phillips, Jennan A; Neyland, Anavernyel

    2016-08-01

    Zika virus (ZIKV) infections are the latest global public health emergency. Occupational health nurses can protect society by educating workers, women of childbearing age, and others traveling in ZIKV-infected areas about prevention strategies. PMID:27411846

  13. Computer Viruses. Technology Update.

    ERIC Educational Resources Information Center

    Ponder, Tim, Comp.; Ropog, Marty, Comp.; Keating, Joseph, Comp.

    This document provides general information on computer viruses, how to help protect a computer network from them, measures to take if a computer becomes infected. Highlights include the origins of computer viruses; virus contraction; a description of some common virus types (File Virus, Boot Sector/Partition Table Viruses, Trojan Horses, and…

  14. Parainfluenza Viruses

    PubMed Central

    Henrickson, Kelly J.

    2003-01-01

    Human parainfluenza viruses (HPIV) were first discovered in the late 1950s. Over the last decade, considerable knowledge about their molecular structure and function has been accumulated. This has led to significant changes in both the nomenclature and taxonomic relationships of these viruses. HPIV is genetically and antigenically divided into types 1 to 4. Further major subtypes of HPIV-4 (A and B) and subgroups/genotypes of HPIV-1 and HPIV-3 have been described. HPIV-1 to HPIV-3 are major causes of lower respiratory infections in infants, young children, the immunocompromised, the chronically ill, and the elderly. Each subtype can cause somewhat unique clinical diseases in different hosts. HPIV are enveloped and of medium size (150 to 250 nm), and their RNA genome is in the negative sense. These viruses belong to the Paramyxoviridae family, one of the largest and most rapidly growing groups of viruses causing significant human and veterinary disease. HPIV are closely related to recently discovered megamyxoviruses (Hendra and Nipah viruses) and metapneumovirus. PMID:12692097

  15. Assessing the impact of climate change on disease emergence in freshwater fish in the United Kingdom.

    PubMed

    Marcos-López, M; Gale, P; Oidtmann, B C; Peeler, E J

    2010-10-01

    A risk framework has been developed to examine the influence of climate change on disease emergence in the United Kingdom. The fish immune response and the replication of pathogens are often correlated with water temperature, which manifest as temperature ranges for infection and clinical diseases. These data are reviewed for the major endemic and exotic disease threats to freshwater fish. Increasing water temperatures will shift the balance in favour of either the host or pathogen, changing the frequency and distribution of disease. A number of endemic diseases of salmonids (e.g. enteric red mouth, furunculosis, proliferative kidney disease and white spot) will become more prevalent and difficult to control as water temperatures increase. Outbreaks of koi herpesvirus in carp fisheries are likely to occur over a longer period each summer. Climate change also alters the threat level associated with exotic pathogens. The risk of viral haemorrhagic septicaemia (VHSV), infectious haematopoietic necrosis virus (IHNV) and spring viraemia of carp virus (SVCV) declines as infection generally only establishes when water temperatures are less than 14°C for VHSV and IHNV and 17°C for SCVC. The risk of establishment of other exotic pathogens (epizootic haematopoietic necrosis and epizootic ulcerative syndrome) increases. The spread of Lactococcus garvieae northwards in Europe is likely to continue, and thus is more likely to be both introduced and become established. Measures to reduce the threat of exotic pathogens need to be revised to account for the changing exotic diseases threat. Increasing water temperatures and the negative effects of extreme weather events (e.g. storms) are likely to alter the freshwater environment adversely for both wild and farmed salmonid populations, increasing their susceptibility to disease and the likelihood of disease emergence. For wild populations, surveillance and risk mitigation need to be focused on locations where disease emergence

  16. Hendra virus

    PubMed Central

    Middleton, Deborah

    2014-01-01

    Synopsis Hendra virus infection of horses occurred sporadically between 1994 and 2010 as a result of spill-over from the viral reservoir in Australian mainland flying-foxes, and occasional onward transmission to people also followed from exposure to affected horses. For reasons that are not well understood an unprecedented number of outbreaks were recorded in 2011, including the first recorded field infection of a dog, leading to heightened community concern. Increasingly, pressure mounted to instigate measures for control of flying-fox numbers, and equine health care workers started to leave the industry on account of risk and liability concerns. Release of an inactivated subunit vaccine for horses against Hendra virus represents the first commercially available product that is focused on mitigating the impact of a Biosafety Level 4 pathogen. Through preventing the development of acute Hendra virus disease in horses, vaccine use is also expected to reduce the risk of transmission of infection to people. This approach to emerging infectious disease management focuses on the role of horses as the proximal cause of human Hendra virus disease, and may assist in redirecting community concerns away from the flying-fox reservoirs, keystone species for the ongoing health of Australia’s native forests. PMID:25281398

  17. [Influenza virus].

    PubMed

    Juozapaitis, Mindaugas; Antoniukas, Linas

    2007-01-01

    Every year, especially during the cold season, many people catch an acute respiratory disease, namely flu. It is easy to catch this disease; therefore, it spreads very rapidly and often becomes an epidemic or a global pandemic. Airway inflammation and other body ailments, which form in a very short period, torment the patient several weeks. After that, the symptoms of the disease usually disappear as quickly as they emerged. The great epidemics of flu have rather unique characteristics; therefore, it is possible to identify descriptions of such epidemics in historic sources. Already in the 4th century bc, Hippocrates himself wrote about one of them. It is known now that flu epidemics emerge rather frequently, but there are no regular intervals between those events. The epidemics can differ in their consequences, but usually they cause an increased mortality of elderly people. The great flu epidemics of the last century took millions of human lives. In 1918-19, during "The Spanish" pandemic of flu, there were around 40-50 millions of deaths all over the world; "Pandemic of Asia" in 1957 took up to one million lives, etc. Influenza virus can cause various disorders of the respiratory system: from mild inflammations of upper airways to acute pneumonia that finally results in the patient's death. Scientist Richard E. Shope, who investigated swine flu in 1920, had a suspicion that the cause of this disease might be a virus. Already in 1933, scientists from the National Institute for Medical Research in London - Wilson Smith, Sir Christopher Andrewes, and Sir Patrick Laidlaw - for the first time isolated the virus, which caused human flu. Then scientific community started the exhaustive research of influenza virus, and the great interest in this virus and its unique features is still active even today.

  18. The Geometry of Viruses.

    ERIC Educational Resources Information Center

    Case, Christine L.

    1991-01-01

    Presented is an activity in which students make models of viruses, which allows them to visualize the shape of these microorganisms. Included are some background on viruses, the biology and geometry of viruses, directions for building viruses, a comparison of cells and viruses, and questions for students. (KR)

  19. Plant Virus Metagenomics: Advances in Virus Discovery.

    PubMed

    Roossinck, Marilyn J; Martin, Darren P; Roumagnac, Philippe

    2015-06-01

    In recent years plant viruses have been detected from many environments, including domestic and wild plants and interfaces between these systems-aquatic sources, feces of various animals, and insects. A variety of methods have been employed to study plant virus biodiversity, including enrichment for virus-like particles or virus-specific RNA or DNA, or the extraction of total nucleic acids, followed by next-generation deep sequencing and bioinformatic analyses. All of the methods have some shortcomings, but taken together these studies reveal our surprising lack of knowledge about plant viruses and point to the need for more comprehensive studies. In addition, many new viruses have been discovered, with most virus infections in wild plants appearing asymptomatic, suggesting that virus disease may be a byproduct of domestication. For plant pathologists these studies are providing useful tools to detect viruses, and perhaps to predict future problems that could threaten cultivated plants.

  20. Zika Virus.

    PubMed

    Musso, Didier; Gubler, Duane J

    2016-07-01

    Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) in the genus Flavivirus and the family Flaviviridae. ZIKV was first isolated from a nonhuman primate in 1947 and from mosquitoes in 1948 in Africa, and ZIKV infections in humans were sporadic for half a century before emerging in the Pacific and the Americas. ZIKV is usually transmitted by the bite of infected mosquitoes. The clinical presentation of Zika fever is nonspecific and can be misdiagnosed as other infectious diseases, especially those due to arboviruses such as dengue and chikungunya. ZIKV infection was associated with only mild illness prior to the large French Polynesian outbreak in 2013 and 2014, when severe neurological complications were reported, and the emergence in Brazil of a dramatic increase in severe congenital malformations (microcephaly) suspected to be associated with ZIKV. Laboratory diagnosis of Zika fever relies on virus isolation or detection of ZIKV-specific RNA. Serological diagnosis is complicated by cross-reactivity among members of the Flavivirus genus. The adaptation of ZIKV to an urban cycle involving humans and domestic mosquito vectors in tropical areas where dengue is endemic suggests that the incidence of ZIKV infections may be underestimated. There is a high potential for ZIKV emergence in urban centers in the tropics that are infested with competent mosquito vectors such as Aedes aegypti and Aedes albopictus.

  1. Zika Virus and Pregnancy

    MedlinePlus

    ... Management Education & Events Advocacy For Patients About ACOG Zika Virus and Pregnancy Home For Patients Zika Virus ... Patient Education Pamphlets - Spanish Share: PEV002, September 2016 Zika Virus and Pregnancy There are risks to your ...

  2. SAMPLING VIRUSES FROM SOIL

    EPA Science Inventory

    This chapter describes in detail methods for detecting viruses of bacteria and humans in soil. Methods also are presented for the assay of these viruses. Reference sources are provided for information on viruses of plants.

  3. Hanta virus (image)

    MedlinePlus

    Hanta virus is a distant cousin of Ebola virus, but is found worldwide. The virus is spread by human contact with rodent waste. Dangerous respiratory illness develops. Effective treatment is not yet ...

  4. Ebola Virus Disease

    MedlinePlus

    ... 2014 Fact sheets Features Commentaries 2014 Multimedia Contacts Ebola virus disease Fact sheet Updated January 2016 Key ... for survivors of Ebola virus disease Symptoms of Ebola virus disease The incubation period, that is, the ...

  5. Computer Viruses: An Overview.

    ERIC Educational Resources Information Center

    Marmion, Dan

    1990-01-01

    Discusses the early history and current proliferation of computer viruses that occur on Macintosh and DOS personal computers, mentions virus detection programs, and offers suggestions for how libraries can protect themselves and their users from damage by computer viruses. (LRW)

  6. Virus Movement Maintains Local Virus Population Diversity

    SciTech Connect

    J. Snyder; B. Wiedenheft; M. Lavin; F. Roberto; J. Spuhler; A. Ortmann; T. Douglas; M. Young

    2007-11-01

    Viruses are the largest reservoir of genetic material on the planet, yet little is known about the population dynamics of any virus within its natural environment. Over a 2-year period, we monitored the diversity of two archaeal viruses found in hot springs within Yellowstone National Park (YNP). Both temporal phylogeny and neutral biodiversity models reveal that virus diversity in these local environments is not being maintained by mutation but rather by high rates of immigration from a globally distributed metacommunity. These results indicate that geographically isolated hot springs are readily able to exchange viruses. The importance of virus movement is supported by the detection of virus particles in air samples collected over YNP hot springs and by their detection in metacommunity sequencing projects conducted in the Sargasso Sea. Rapid rates of virus movement are not expected to be unique to these archaeal viruses but rather a common feature among virus metacommunities. The finding that virus immigration rather than mutation can dominate community structure has significant implications for understanding virus circulation and the role that viruses play in ecology and evolution by providing a reservoir of mobile genetic material.

  7. Vaccination against enteric septicaemia of catfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Edwardsiella ictaluri, the causative agent of enteric septicemia (ESC) of catfish, is one of the most economically important diseases of cultured channel catfish. In 2002, Wagner and coworkers reported that enteric septicemia of catfish (ESC) and columnaris (Flavobacterium columnaris) were the two m...

  8. Viruses and Virus Diseases of Rubus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rubus species are propagated vegetatively and are subject to infection by viruses during development, propagation and fruit production stages. Reports of initial detection and symptoms of more than 30 viruses, virus-like diseases and phytoplasmas affecting Rubus spp. have been reviewed more than 20 ...

  9. Crystallization of viruses and virus proteins

    NASA Astrophysics Data System (ADS)

    Sehnke, Paul C.; Harrington, Melissa; Hosur, M. V.; Li, Yunge; Usha, R.; Craig Tucker, R.; Bomu, Wu; Stauffacher, Cynthia V.; Johnson, John E.

    1988-07-01

    Methods for crystallizing six isometric plant and insect viruses are presented. Procedures developed for modifying, purifying and crystallizing coat protein subunits isolated from a virus forming asymmetric, spheroidal particles, stabilized almost exclusively by protein-RNA interactions, are also discussed. The tertiary and quaternary structures of small RNA viruses are compared.

  10. Comparative study of CXC chemokines modulation in brown trout (Salmo trutta) following infection with a bacterial or viral pathogen.

    PubMed

    Gorgoglione, Bartolomeo; Zahran, Eman; Taylor, Nick G H; Feist, Stephen W; Zou, Jun; Secombes, Christopher J

    2016-03-01

    Chemokine modulation in response to pathogens still needs to be fully characterised in fish, in view of the recently described novel chemokines present. This paper reports the first comparative study of CXC chemokine genes transcription in salmonids (brown trout), with a particular focus on the fish specific CXC chemokines (CXCL_F). Adopting new primer sets, optimised to specifically target mRNA, a RT-qPCR gene screening was carried out. Constitutive gene expression was assessed first in six tissues from SPF brown trout. Transcription modulation was next investigated in kidney and spleen during septicaemic infection induced by a RNA virus (Viral Haemorrhagic Septicaemia virus, genotype Ia) or by a Gram negative bacterium (Yersinia ruckeri, ser. O1/biot. 2). From each target organ specific pathogen burden, measured detecting VHSV-glycoprotein or Y. ruckeri 16S rRNA, and IFN-γ gene expression were analysed for their correlation to chemokine transcription. Both pathogens modulated CXC chemokine gene transcript levels, with marked up-regulation seen in some cases, and with both temporal and tissue specific effects apparent. For example, Y. ruckeri strongly induced chemokine transcription in spleen within 24h, whilst VHS generally induced the largest increases at 3d.p.i. in both tissues. This study gives clues to the role of the novel CXC chemokines, in comparison to the other known CXC chemokines in salmonids. PMID:26866873

  11. Comparative study of CXC chemokines modulation in brown trout (Salmo trutta) following infection with a bacterial or viral pathogen.

    PubMed

    Gorgoglione, Bartolomeo; Zahran, Eman; Taylor, Nick G H; Feist, Stephen W; Zou, Jun; Secombes, Christopher J

    2016-03-01

    Chemokine modulation in response to pathogens still needs to be fully characterised in fish, in view of the recently described novel chemokines present. This paper reports the first comparative study of CXC chemokine genes transcription in salmonids (brown trout), with a particular focus on the fish specific CXC chemokines (CXCL_F). Adopting new primer sets, optimised to specifically target mRNA, a RT-qPCR gene screening was carried out. Constitutive gene expression was assessed first in six tissues from SPF brown trout. Transcription modulation was next investigated in kidney and spleen during septicaemic infection induced by a RNA virus (Viral Haemorrhagic Septicaemia virus, genotype Ia) or by a Gram negative bacterium (Yersinia ruckeri, ser. O1/biot. 2). From each target organ specific pathogen burden, measured detecting VHSV-glycoprotein or Y. ruckeri 16S rRNA, and IFN-γ gene expression were analysed for their correlation to chemokine transcription. Both pathogens modulated CXC chemokine gene transcript levels, with marked up-regulation seen in some cases, and with both temporal and tissue specific effects apparent. For example, Y. ruckeri strongly induced chemokine transcription in spleen within 24h, whilst VHS generally induced the largest increases at 3d.p.i. in both tissues. This study gives clues to the role of the novel CXC chemokines, in comparison to the other known CXC chemokines in salmonids.

  12. The Tobacco Mosaic Virus.

    ERIC Educational Resources Information Center

    Sulzinski, Michael A.

    1992-01-01

    Explains how the tobacco mosaic virus can be used to study virology. Presents facts about the virus, procedures to handle the virus in the laboratory, and four laboratory exercises involving the viruses' survival under inactivating conditions, dilution end point, filterability, and microscopy. (MDH)

  13. Viruses of potato.

    PubMed

    Loebenstein, Gad; Gaba, Victor

    2012-01-01

    Potatoes are an important crop in Mediterranean countries both for local consumption and for export to other countries, mainly during the winter. Many Mediterranean countries import certified seed potato in addition to their own seed production. The local seeds are mainly used for planting in the autumn and winter, while the imported seed are used for early and late spring plantings. Potato virus Y is the most important virus in Mediterranean countries, present mainly in the autumn plantings. The second important virus is Potato leafroll virus, though in recent years its importance seems to be decreasing. Potato virus X, Potato virus A, Potato virus S, Potato virus M, and the viroid, Potato spindle tuber viroid, were also recorded in several Mediterranean countries. For each virus the main strains, transmission, characterization of the virus particle, its genome organization, detection, and control methods including transgenic approaches will be discussed. PMID:22682169

  14. Understanding Ebola Virus Transmission

    PubMed Central

    Judson, Seth; Prescott, Joseph; Munster, Vincent

    2015-01-01

    An unprecedented number of Ebola virus infections among healthcare workers and patients have raised questions about our understanding of Ebola virus transmission. Here, we explore different routes of Ebola virus transmission between people, summarizing the known epidemiological and experimental data. From this data, we expose important gaps in Ebola virus research pertinent to outbreak situations. We further propose experiments and methods of data collection that will enable scientists to fill these voids in our knowledge about the transmission of Ebola virus. PMID:25654239

  15. Virus-Vectored Influenza Virus Vaccines

    PubMed Central

    Tripp, Ralph A.; Tompkins, S. Mark

    2014-01-01

    Despite the availability of an inactivated vaccine that has been licensed for >50 years, the influenza virus continues to cause morbidity and mortality worldwide. Constant evolution of circulating influenza virus strains and the emergence of new strains diminishes the effectiveness of annual vaccines that rely on a match with circulating influenza strains. Thus, there is a continued need for new, efficacious vaccines conferring cross-clade protection to avoid the need for biannual reformulation of seasonal influenza vaccines. Recombinant virus-vectored vaccines are an appealing alternative to classical inactivated vaccines because virus vectors enable native expression of influenza antigens, even from virulent influenza viruses, while expressed in the context of the vector that can improve immunogenicity. In addition, a vectored vaccine often enables delivery of the vaccine to sites of inductive immunity such as the respiratory tract enabling protection from influenza virus infection. Moreover, the ability to readily manipulate virus vectors to produce novel influenza vaccines may provide the quickest path toward a universal vaccine protecting against all influenza viruses. This review will discuss experimental virus-vectored vaccines for use in humans, comparing them to licensed vaccines and the hurdles faced for licensure of these next-generation influenza virus vaccines. PMID:25105278

  16. Viruses infecting reptiles.

    PubMed

    Marschang, Rachel E

    2011-11-01

    A large number of viruses have been described in many different reptiles. These viruses include arboviruses that primarily infect mammals or birds as well as viruses that are specific for reptiles. Interest in arboviruses infecting reptiles has mainly focused on the role reptiles may play in the epidemiology of these viruses, especially over winter. Interest in reptile specific viruses has concentrated on both their importance for reptile medicine as well as virus taxonomy and evolution. The impact of many viral infections on reptile health is not known. Koch's postulates have only been fulfilled for a limited number of reptilian viruses. As diagnostic testing becomes more sensitive, multiple infections with various viruses and other infectious agents are also being detected. In most cases the interactions between these different agents are not known. This review provides an update on viruses described in reptiles, the animal species in which they have been detected, and what is known about their taxonomic positions.

  17. Viruses Infecting Reptiles

    PubMed Central

    Marschang, Rachel E.

    2011-01-01

    A large number of viruses have been described in many different reptiles. These viruses include arboviruses that primarily infect mammals or birds as well as viruses that are specific for reptiles. Interest in arboviruses infecting reptiles has mainly focused on the role reptiles may play in the epidemiology of these viruses, especially over winter. Interest in reptile specific viruses has concentrated on both their importance for reptile medicine as well as virus taxonomy and evolution. The impact of many viral infections on reptile health is not known. Koch’s postulates have only been fulfilled for a limited number of reptilian viruses. As diagnostic testing becomes more sensitive, multiple infections with various viruses and other infectious agents are also being detected. In most cases the interactions between these different agents are not known. This review provides an update on viruses described in reptiles, the animal species in which they have been detected, and what is known about their taxonomic positions. PMID:22163336

  18. Morphogenesis of Bittner Virus

    PubMed Central

    Gay, Frederick W.; Clarke, John K.; Dermott, Evelyn

    1970-01-01

    The morphogenesis of Bittner virus (mouse mammary tumor virus) was studied in sectioned mammary tumor cells. Internal components of the virus (type A particles) were seen being assembled in virus factories close to the nucleus and were also seen forming at the plasma membrane. The particles in virus factories became enveloped by budding through the membrane of cytoplasmic vacuoles which were derived from dilated endoplasmic reticulum. Complete virus particles were liberated from these vacuoles by cell lysis. Particles budding at the plasma membrane were released into intercellular spaces. Maturation of enveloped virus occurred after release, but mature internal components were rarely seen in the cytoplasm before envelopment. Direct cell-to-cell transfer of virus by pinocytosis of budding particles by an adjacent cell was observed, and unusual forms of budding virus which participated in this process are illustrated and described. There was evidence that some virus particles contained cytoplasmic constituents, including ribosomes. Certain features of the structure of internal components are discussed in relation to a recently proposed model for the internal component of the mouse leukemia virus. Intracisternal virus-like particles were occasionally seen in tumor cells, but there was no evidence that these structures were developmentally related to Bittner virus. Images PMID:4193837

  19. Morphogenesis of Bittner virus.

    PubMed

    Gay, F W; Clarke, J K; Dermott, E

    1970-06-01

    The morphogenesis of Bittner virus (mouse mammary tumor virus) was studied in sectioned mammary tumor cells. Internal components of the virus (type A particles) were seen being assembled in virus factories close to the nucleus and were also seen forming at the plasma membrane. The particles in virus factories became enveloped by budding through the membrane of cytoplasmic vacuoles which were derived from dilated endoplasmic reticulum. Complete virus particles were liberated from these vacuoles by cell lysis. Particles budding at the plasma membrane were released into intercellular spaces. Maturation of enveloped virus occurred after release, but mature internal components were rarely seen in the cytoplasm before envelopment. Direct cell-to-cell transfer of virus by pinocytosis of budding particles by an adjacent cell was observed, and unusual forms of budding virus which participated in this process are illustrated and described. There was evidence that some virus particles contained cytoplasmic constituents, including ribosomes. Certain features of the structure of internal components are discussed in relation to a recently proposed model for the internal component of the mouse leukemia virus. Intracisternal virus-like particles were occasionally seen in tumor cells, but there was no evidence that these structures were developmentally related to Bittner virus. PMID:4193837

  20. Respiratory Syncytial Virus Infections

    MedlinePlus

    Respiratory syncytial virus (RSV) causes mild, cold-like symptoms in adults and older healthy children. It can cause serious problems in ... tests can tell if your child has the virus. There is no specific treatment. You should give ...

  1. Viruses and human cancer

    SciTech Connect

    Gallo, R.C.; Haseltine, W.; Klein, G.; Zur Hausen, H.

    1987-01-01

    This book contains papers on the following topics: Immunology and Epidemiology, Biology and Pathogenesis, Models of Pathogenesis and Treatment, Simian and Bovine Retroviruses, Human Papilloma Viruses, EBV and Herpesvirus, and Hepatitis B Virus.

  2. Densonucleosis virus structural proteins.

    PubMed

    Kelly, D C; Moore, N F; Spilling, C R; Barwise, A H; Walker, I O

    1980-10-01

    The protein coats of two densonucleosis viruses (types 1 and 2) were examined by a variety of biophysical, biochemical, and serological techniques. The viruses were 24 nm in diameter, contained at least four polypeptides, were remarkably stable to extremes of pH and denaturing agents, and were serologically closely related. The two viruses could, however, be distinguished serologically and by differences in migration of their structural polypeptides. For each virus the "top component" (i.e., the protein coat minus DNA, found occurring naturally in infections) appeared to have a composition identical to that of the coat of the virus and was a more stable structure. Electrometric titration curves of the virus particles and top components demonstrated that the DNA phosphate in densonucleosis virus particles was neutralized by cations other than basic amino acid side chains of the protein coat. Circular dichroism studies showed that there was a conformational difference between the protein coats of top components and virus particles.

  3. Viruses and Breast Cancer

    PubMed Central

    Lawson, James S.; Heng, Benjamin

    2010-01-01

    Viruses are the accepted cause of many important cancers including cancers of the cervix and anogenital area, the liver, some lymphomas, head and neck cancers and indirectly human immunodeficiency virus associated cancers. For over 50 years, there have been serious attempts to identify viruses which may have a role in breast cancer. Despite these efforts, the establishment of conclusive evidence for such a role has been elusive. However, the development of extremely sophisticated new experimental techniques has allowed the recent development of evidence that human papilloma virus, Epstein-Barr virus, mouse mammary tumor virus and bovine leukemia virus may each have a role in the causation of human breast cancers. This is potentially good news as effective vaccines are already available to prevent infections from carcinogenic strains of human papilloma virus, which causes cancer of the uterine cervix. PMID:24281093

  4. Zika Virus Fact Sheet

    MedlinePlus

    ... 2014 Fact sheets Features Commentaries 2014 Multimedia Contacts Zika virus Fact sheet Updated 6 September 2016 Key facts ... and last for 2-7 days. Complications of Zika virus disease After a comprehensive review of evidence, there ...

  5. Human Parainfluenza Viruses

    MedlinePlus

    ... HPIVs Are Not the Same as Influenza (Flu) Viruses People usually get HPIV infections more often in ... hands, and touching objects or surfaces with the viruses on them then touching your mouth, nose, or ...

  6. Herpes Simplex Virus (HSV)

    MedlinePlus

    ... rashes clinical tools newsletter | contact Share | Herpes Simplex Virus (HSV) A parent's guide to condition and treatment ... skin or mouth sores with the herpes simplex virus (HSV) is called primary herpes. This may be ...

  7. Tumorigenic DNA viruses

    SciTech Connect

    Klein, G.

    1989-01-01

    The eighth volume of Advances in Viral Oncology focuses on the three major DNA virus groups with a postulated or proven tumorigenic potential: papillomaviruses, animal hepatitis viruses, and the Epstein-Bar virus. In the opening chapters, the contributors analyze the evidence that papillomaviruses and animal hepatitis viruses are involved in tumorigenesis and describe the mechanisms that trigger virus-host cell interactions. A detailed section on the Epstein-Barr virus (EBV) - comprising more than half the book - examines the transcription and mRNA processing patterns of the virus genome; the mechanisms by which EBV infects lymphoid and epithelial cells; the immunological aspects of the virus; the actions of EBV in hosts with Acquired Immune Deficiency Syndrome; and the involvement of EBV in the etiology of Burkitt's lymphoma.

  8. Advances in virus research

    SciTech Connect

    Maramorosch, K. ); Murphy, F.A. ); Shatkin, A.J. )

    1988-01-01

    This book contains eight chapters. Some of the titles are: Initiation of viral DNA replication; Vaccinia: virus, vector, vaccine; The pre-S region of hepadnavirus envelope proteins; and Archaebacterial viruses.

  9. West Nile virus

    MedlinePlus

    ... believe West Nile virus is spread when a mosquito bites an infected bird and then bites a person. ... avoid getting West Nile virus infection after a mosquito bite. People in good health generally do not develop ...

  10. Virus Assembly and Maturation

    NASA Astrophysics Data System (ADS)

    Johnson, John E.

    2004-03-01

    We use two techniques to look at three-dimensional virus structure: electron cryomicroscopy (cryoEM) and X-ray crystallography. Figure 1 is a gallery of virus particles whose structures Timothy Baker, one of my former colleagues at Purdue University, used cryoEM to determine. It illustrates the variety of sizes of icosahedral virus particles. The largest virus particle on this slide is the Herpes simplex virus, around 1200Å in diameter; the smallest we examined was around 250Å in diameter. Viruses bear their genomic information either as positive-sense DNA and RNA, double-strand DNA, double-strand RNA, or negative-strand RNA. Viruses utilize the various structure and function "tactics" seen throughout cell biology to replicate at high levels. Many of the biological principles that we consider general were in fact discovered in the context of viruses ...

  11. Avian influenza virus and Newcastle disease virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus (AIV) and Newcastle disease virus (NDV) severely impact poultry egg production. Decreased egg yield and hatchability, as well as misshapen eggs, are often observed during infection with AIV and NDV, even with low-virulence strains or in vaccinated flocks. Data suggest that in...

  12. Computer Virus Protection

    ERIC Educational Resources Information Center

    Rajala, Judith B.

    2004-01-01

    A computer virus is a program--a piece of executable code--that has the unique ability to replicate. Like biological viruses, computer viruses can spread quickly and are often difficult to eradicate. They can attach themselves to just about any type of file, and are spread by replicating and being sent from one individual to another. Simply having…

  13. Avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus (AIV) is type A influenza, which is adapted to an avian host. Although avian influenza has been isolated from numerous avian species, the primary natural hosts for the virus are dabbling ducks, shorebirds, and gulls. The virus can be found world-wide in these species and in o...

  14. Respiratory Syncytial Virus

    MedlinePlus

    ... Palsy: Shannon's Story" 5 Things to Know About Zika & Pregnancy Respiratory Syncytial Virus KidsHealth > For Parents > Respiratory Syncytial Virus Print A ... often get it when older kids carry the virus home from school and pass it to ... often happen in epidemics that last from late fall through early spring. ...

  15. Zika virus - an overview.

    PubMed

    Zanluca, Camila; Dos Santos, Claudia Nunes Duarte

    2016-05-01

    Zika virus (ZIKV) is currently one of the most important emerging viruses in the world. Recently, it has caused outbreaks and epidemics, and has been associated with severe clinical manifestations and congenital malformations. However to date, little is known about the pathogenicity of the virus and the consequences of ZIKV infection. In this paper, we provide an overview of the current knowledge on ZIKV.

  16. A molluscan calreticulin ortholog from Haliotis discus discus: Molecular characterization and transcriptional evidence for its role in host immunity.

    PubMed

    Udayantha, H M V; Godahewa, G I; Bathige, S D N K; Wickramaarachchi, W D Niroshana; Umasuthan, Navaneethaiyer; De Zoysa, Mahanama; Jeong, Hyung-Bok; Lim, Bong-Soo; Lee, Jehee

    2016-05-20

    Calreticulin (CALR), a Ca(2+) binding chaperone of the endoplasmic reticulum (ER) and mainly involved in Ca(2+) storage and signaling. In this study, we report the molecular characterization and immune responses of CALR homolog from disk abalone (AbCALR). The full length AbCALR cDNA (1837 bp) had an ORF of 1224 bp. According to the multiple alignments analysis, N- and P-domains were highly conserved in all the selected members of CALRs. In contrast, the C-domain which terminated with the characteristic ER retrieval signal (HDEL) was relatively less conserved. The phylogenetic analysis showed that all the selected molluscan homologs clustered together. Genomic sequence of AbCALR revealed that cDNA sequence was dispersed into ten exons interconnected with nine introns. AbCALR mRNA expression shows the significant (P < 0.05) up-regulation of AbCALR transcripts in hemocytes upon bacterial (Listeria monocytogenes and Vibrio parahaemolyticus), viral (Viral haemorrhagic septicaemia virus; VHSV) and immune stimulants (LPS and poly I:C) challenges at middle and/or late phases. These results collectively implied that AbCALR is able to be stimulated by pathogenic signals and might play a potential role in host immunity. PMID:27086846

  17. A molluscan calreticulin ortholog from Haliotis discus discus: Molecular characterization and transcriptional evidence for its role in host immunity.

    PubMed

    Udayantha, H M V; Godahewa, G I; Bathige, S D N K; Wickramaarachchi, W D Niroshana; Umasuthan, Navaneethaiyer; De Zoysa, Mahanama; Jeong, Hyung-Bok; Lim, Bong-Soo; Lee, Jehee

    2016-05-20

    Calreticulin (CALR), a Ca(2+) binding chaperone of the endoplasmic reticulum (ER) and mainly involved in Ca(2+) storage and signaling. In this study, we report the molecular characterization and immune responses of CALR homolog from disk abalone (AbCALR). The full length AbCALR cDNA (1837 bp) had an ORF of 1224 bp. According to the multiple alignments analysis, N- and P-domains were highly conserved in all the selected members of CALRs. In contrast, the C-domain which terminated with the characteristic ER retrieval signal (HDEL) was relatively less conserved. The phylogenetic analysis showed that all the selected molluscan homologs clustered together. Genomic sequence of AbCALR revealed that cDNA sequence was dispersed into ten exons interconnected with nine introns. AbCALR mRNA expression shows the significant (P < 0.05) up-regulation of AbCALR transcripts in hemocytes upon bacterial (Listeria monocytogenes and Vibrio parahaemolyticus), viral (Viral haemorrhagic septicaemia virus; VHSV) and immune stimulants (LPS and poly I:C) challenges at middle and/or late phases. These results collectively implied that AbCALR is able to be stimulated by pathogenic signals and might play a potential role in host immunity.

  18. The taxonomy of viruses should include viruses.

    PubMed

    Calisher, Charles H

    2016-05-01

    Having lost sight of its goal, the International Committee on Taxonomy of Viruses has redoubled its efforts. That goal is to arrive at a consensus regarding virus classification, i.e., proper placement of viruses in a hierarchical taxonomic scheme; not an easy task given the wide variety of recognized viruses. Rather than suggesting a continuation of the bureaucratic machinations of the past, this opinion piece is a call for insertion of common sense in sorting out the avalanche of information already, and soon-to-be, accrued data. In this way information about viruses ideally would be taxonomically correct as well as useful to working virologists and journal editors, rather than being lost, minimized, or ignored.

  19. Viruses of asparagus.

    PubMed

    Tomassoli, Laura; Tiberini, Antonio; Vetten, Heinrich-Josef

    2012-01-01

    The current knowledge on viruses infecting asparagus (Asparagus officinalis) is reviewed. Over half a century, nine virus species belonging to the genera Ilarvirus, Cucumovirus, Nepovirus, Tobamovirus, Potexvirus, and Potyvirus have been found in this crop. The potyvirus Asparagus virus 1 (AV1) and the ilarvirus Asparagus virus 2 (AV2) are widespread and negatively affect the economic life of asparagus crops reducing yield and increasing the susceptibility to biotic and abiotic stress. The main properties and epidemiology of AV1 and AV2 as well as diagnostic techniques for their detection and identification are described. Minor viruses and control are briefly outlined.

  20. Viruses of asparagus.

    PubMed

    Tomassoli, Laura; Tiberini, Antonio; Vetten, Heinrich-Josef

    2012-01-01

    The current knowledge on viruses infecting asparagus (Asparagus officinalis) is reviewed. Over half a century, nine virus species belonging to the genera Ilarvirus, Cucumovirus, Nepovirus, Tobamovirus, Potexvirus, and Potyvirus have been found in this crop. The potyvirus Asparagus virus 1 (AV1) and the ilarvirus Asparagus virus 2 (AV2) are widespread and negatively affect the economic life of asparagus crops reducing yield and increasing the susceptibility to biotic and abiotic stress. The main properties and epidemiology of AV1 and AV2 as well as diagnostic techniques for their detection and identification are described. Minor viruses and control are briefly outlined. PMID:22682173

  1. Serodiagnosis for Tumor Viruses

    PubMed Central

    Morrison, Brian J.; Labo, Nazzarena; Miley, Wendell J.; Whitby, Denise

    2015-01-01

    The known human tumor viruses include the DNA viruses Epstein-Barr virus, Kaposi sarcoma herpesvirus, Merkel cell polyomavirus, human papillomavirus, and hepatitis B virus. RNA tumor viruses include Human T-cell lymphotrophic virus type-1 and hepatitis C virus. The serological identification of antigens/antibodies in plasma serum is a rapidly progressing field with utility for both scientists and clinicians. Serology is useful for conducting seroepidemiology studies and to inform on the pathogenesis and host immune response to a particular viral agent. Clinically, serology is useful for diagnosing current or past infection and for aiding in clinical management decisions. Serology is useful for screening blood donations for infectious agents and for monitoring the outcome of vaccination against these viruses. Serodiagnosis of human tumor viruses has improved in recent years with increased specificity and sensitivity of the assays, as well as reductions in cost and the ability to assess multiple antibody/antigens in single assays. Serodiagnosis of tumor viruses plays an important role in our understanding of the prevalence and transmission of these viruses and ultimately in the ability to develop treatments/preventions for these globally important diseases. PMID:25843726

  2. Discovering novel zoonotic viruses.

    PubMed

    Wang, Lin-Fa

    2011-07-01

    From the emergence of Hendra virus and Menangle virus in Australia to the global pandemics of severe acute respiratory syndrome and influenza viruses (both H5N1 and H1N1), there has been a surge of zoonotic virus outbreaks in the last two decades. Although the drivers for virus emergence remain poorly understood, the rate of discovery of new viruses is accelerating. This is due to a combination of true emergence of new pathogens and the advance of new technologies making rapid detection and characterisation possible. While molecular approaches will continue to lead the way in virus discovery, other technological platforms are required to increase the chance of success. The lessons learnt in the last 20 years confirm that the One Health approach, involving inclusive collaborations between physicians, veterinarians and other health and environmental professionals, will be the key to combating future zoonotic disease outbreaks.

  3. Virus-Associated Lymphomagenesis

    PubMed Central

    Tarantul, V. Z.

    2006-01-01

    At least 2 billion people are affected by viral infections worldwide. The infections induce a lot of various human diseases and are one of the main causes of human mortality. In particular, they can lead to development of various human cancers. Up to 15-20% of human cancer incidence can be attributed to viruses. Although viral infections are very common in the general population, only few of them result in clinically relevant lesions. Certain associations between virus infections and malignancy are strong and irrefutable, the others are still speculative. The criteria most often used for determining the causality are the consistence of the association, either epidemiologic or at the molecular level, and oncogenicity of viruses or particular viral genes in animal models or cell cultures. Due to some ambiguity of such a determination, it is instructive to consider by specific cases what evidence is generally accepted as sufficient to establish a causal relation between virus and cancer. Lymphomas are one of the best studied cancer types closely associated with a small but definite range of viruses. Numerous data show a close interrelation between lymphomagenesis and infection by such viruses as Kaposi’s sarcoma herpesvirus (KSHV), Epstein-Barr virus (EBV), hepatitis C virus (HCV), human T-cell leukemia virus (HTLV), and human immunodeficiency virus (HIV). For instance, experiments on monkeys artificially infected with viruses and data on anti-cancer effect of specific antiviral preparations strongly suggest the involvement of viruses in lymphoma development. The present review is devoted to the association of different viruses with human lymphomas and to viral genes potentially involved in the neoplastic process. The recognition of virus involvement in lymphomagenesis may facilitate new strategies for cancer therapy, diagnosis and screening and can lead to a reduction in the number of individuals at risk of disease. PMID:23674972

  4. [The great virus comeback].

    PubMed

    Forterre, Patrick

    2013-01-01

    Viruses have been considered for a long time as by-products of biological evolution. This view is changing now as a result of several recent discoveries. Viral ecologists have shown that viral particles are the most abundant biological entities on our planet, whereas metagenomic analyses have revealed an unexpected abundance and diversity of viral genes in the biosphere. Comparative genomics have highlighted the uniqueness of viral sequences, in contradiction with the traditional view of viruses as pickpockets of cellular genes. On the contrary, cellular genomes, especially eukaryotic ones, turned out to be full of genes derived from viruses or related elements (plasmids, transposons, retroelements and so on). The discovery of unusual viruses infecting archaea has shown that the viral world is much more diverse than previously thought, ruining the traditional dichotomy between bacteriophages and viruses. Finally, the discovery of giant viruses has blurred the traditional image of viruses as small entities. Furthermore, essential clues on virus history have been obtained in the last ten years. In particular, structural analyses of capsid proteins have uncovered deeply rooted homologies between viruses infecting different cellular domains, suggesting that viruses originated before the last universal common ancestor (LUCA). These studies have shown that several lineages of viruses originated independently, i.e., viruses are polyphyletic. From the time of LUCA, viruses have coevolved with their hosts, and viral lineages can be viewed as lianas wrapping around the trunk, branches and leaves of the tree of life. Although viruses are very diverse, with genomes encoding from one to more than one thousand proteins, they can all be simply defined as organisms producing virions. Virions themselves can be defined as infectious particles made of at least one protein associated with the viral nucleic acid, endowed with the capability to protect the viral genome and ensure its

  5. Viruses of botrytis.

    PubMed

    Pearson, Michael N; Bailey, Andrew M

    2013-01-01

    Botrytis cinerea (gray mold) is one of the most widespread and destructive fungal diseases of horticultural crops. Propagation and dispersal is usually by asexual conidia but the sexual stage (Botryotinia fuckeliana (de Bary) Whetzel) also occurs in nature. DsRNAs, indicative of virus infection, are common in B. cinerea, but only four viruses (Botrytis virus F (BVF), Botrytis virus X (BVX), Botrytis cinerea mitovirus 1 (BcMV1), and Botrytis porri RNA virus) have been sequenced. BVF and BVX are unusual mycoviruses being ssRNA flexous rods and have been designated the type species of the genera Mycoflexivirus and Botrexvirus (family Betaflexivirdae), respectively. The reported effects of viruses on Botrytis range from negligible to severe, with Botrytis cinerea mitovirus 1 causing hypovirulence. Little is currently known about the effects of viruses on Botrytis metabolism but recent complete sequencing of the B. cinerea genome now provides an opportunity to investigate the host-pathogen interactions at the molecular level. There is interest in the possible use of mycoviruses as biological controls for Botrytis because of the common problem of fungicide resistance. Unfortunately, hyphal anastomosis is the only known mechanism of horizontal virus transmission and the large number of vegetative incompatibility groups in Botrytis is a potential constraint on the spread of an introduced virus. Although some Botrytis viruses, such as BVF and BVX, are known to have international distribution, there is a distinct lack of epidemiological data and the means of spread are unknown.

  6. RNA Viruses Infecting Pest Insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    RNA viruses are viruses whose genetic material is ribonucleic acid (RNA). RNA viruses may be double or single-stranded based on the type of RNA they contain. Single-stranded RNA viruses can be further grouped into negative sense or positive-sense viruses according to the polarity of their RNA. Fur...

  7. Postmortem stability of Ebola virus.

    PubMed

    Prescott, Joseph; Bushmaker, Trenton; Fischer, Robert; Miazgowicz, Kerri; Judson, Seth; Munster, Vincent J

    2015-05-01

    The ongoing Ebola virus outbreak in West Africa has highlighted questions regarding stability of the virus and detection of RNA from corpses. We used Ebola virus-infected macaques to model humans who died of Ebola virus disease. Viable virus was isolated <7 days posteuthanasia; viral RNA was detectable for 10 weeks.

  8. Water system virus detection

    NASA Technical Reports Server (NTRS)

    Fraser, A. S.; Wells, A. F.; Tenoso, H. J. (Inventor)

    1978-01-01

    The performance of a waste water reclamation system is monitored by introducing a non-pathogenic marker virus, bacteriophage F2, into the waste-water prior to treatment and, thereafter, testing the reclaimed water for the presence of the marker virus. A test sample is first concentrated by absorbing any marker virus onto a cellulose acetate filter in the presence of a trivalent cation at low pH and then flushing the filter with a limited quantity of a glycine buffer solution to desorb any marker virus present on the filter. Photo-optical detection of indirect passive immune agglutination by polystyrene beads indicates the performance of the water reclamation system in removing the marker virus. A closed system provides for concentrating any marker virus, initiating and monitoring the passive immune agglutination reaction, and then flushing the system to prepare for another sample.

  9. Constructing computer virus phylogenies

    SciTech Connect

    Goldberg, L.A.; Goldberg, P.W.; Phillips, C.A.; Sorkin, G.B.

    1996-03-01

    There has been much recent algorithmic work on the problem of reconstructing the evolutionary history of biological species. Computer virus specialists are interested in finding the evolutionary history of computer viruses--a virus is often written using code fragments from one or more other viruses, which are its immediate ancestors. A phylogeny for a collection of computer viruses is a directed acyclic graph whose nodes are the viruses and whose edges map ancestors to descendants and satisfy the property that each code fragment is ``invented`` only once. To provide a simple explanation for the data, we consider the problem of constructing such a phylogeny with a minimal number of edges. In general, this optimization problem cannot be solved in quasi-polynomial time unless NQP=QP; we present positive and negative results for associated approximated problems. When tree solutions exist, they can be constructed and randomly sampled in polynomial time.

  10. Viruses within animal genomes.

    PubMed

    De Brognier, A; Willems, L

    2016-04-01

    Viruses and their hosts can co-evolve to reach a fragile equilibrium that allows the survival of both. An excess of pathogenicity in the absence of a reservoir would be detrimental to virus survival. A significant proportion of all animal genomes has been shaped by the insertion of viruses that subsequently became 'fossilised'. Most endogenous viruses have lost the capacity to replicate via an infectious cycle and now replicate passively. The insertion of endogenous viruses has contributed to the evolution of animal genomes, for example in the reproductive biology of mammals. However, spontaneous viral integration still occasionally occurs in a number of virus-host systems. This constitutes a potential risk to host survival but also provides an opportunity for diversification and evolution.

  11. Viruses of lower vertebrates.

    PubMed

    Essbauer, S; Ahne, W

    2001-08-01

    Viruses of lower vertebrates recently became a field of interest to the public due to increasing epizootics and economic losses of poikilothermic animals. These were reported worldwide from both wildlife and collections of aquatic poikilothermic animals. Several RNA and DNA viruses infecting fish, amphibians and reptiles have been studied intensively during the last 20 years. Many of these viruses induce diseases resulting in important economic losses of lower vertebrates, especially in fish aquaculture. In addition, some of the DNA viruses seem to be emerging pathogens involved in the worldwide decline in wildlife. Irido-, herpes- and polyomavirus infections may be involved in the reduction in the numbers of endangered amphibian and reptile species. In this context the knowledge of several important RNA viruses such as orthomyxo-, paramyxo-, rhabdo-, retro-, corona-, calici-, toga-, picorna-, noda-, reo- and birnaviruses, and DNA viruses such as parvo-, irido-, herpes-, adeno-, polyoma- and poxviruses, is described in this review. PMID:11550762

  12. Viruses in Antarctic lakes

    NASA Technical Reports Server (NTRS)

    Kepner, R. L. Jr; Wharton, R. A. Jr; Suttle, C. A.; Wharton RA, J. r. (Principal Investigator)

    1998-01-01

    Water samples collected from four perennially ice-covered Antarctic lakes during the austral summer of 1996-1997 contained high densities of extracellular viruses. Many of these viruses were found to be morphologically similar to double-stranded DNA viruses that are known to infect algae and protozoa. These constitute the first observations of viruses in perennially ice-covered polar lakes. The abundance of planktonic viruses and data suggesting substantial production potential (relative to bacteria] secondary and photosynthetic primary production) indicate that viral lysis may be a major factor in the regulation of microbial populations in these extreme environments. Furthermore, we suggest that Antarctic lakes may be a reservoir of previously undescribed viruses that possess novel biological and biochemical characteristics.

  13. The human oncogenic viruses

    SciTech Connect

    Luderer, A.A.; Weetall, H.H

    1986-01-01

    This book contains eight selections. The titles are: Cytogenetics of the Leukemias and Lymphomas; Cytogenetics of Solid Tumors: Renal Cell Carcinoma, Malignant Melanoma, Retinoblastoma, and Wilms' Tumor; Elucidation of a Normal Function for a Human Proto-Oncogene; Detection of HSV-2 Genes and Gene Products in Cervical Neoplasia; Papillomaviruses in Anogennital Neoplasms; Human Epstein-Barr Virus and Cancer; Hepatitis B Virus and Hepatocellular Carcinoma; and Kaposi's Sarcoma: Acquired Immunodeficiency Syndrome (AIDS) and Associated Viruses.

  14. The contribution of molecular epidemiology to the understanding and control of viral diseases of salmonid aquaculture.

    PubMed

    Snow, Michael

    2011-01-01

    Molecular epidemiology is a science which utilizes molecular biology to define the distribution of disease in a population (descriptive epidemiology) and relies heavily on integration of traditional (or analytical) epidemiological approaches to identify the etiological determinants of this distribution. The study of viral pathogens of aquaculture has provided many exciting opportunities to apply such tools. This review considers the extent to which molecular epidemiological studies have contributed to better understanding and control of disease in aquaculture, drawing on examples of viral diseases of salmonid fish of commercial significance including viral haemorrhagic septicaemia virus (VHSV), salmonid alphavirus (SAV) and infectious salmon anaemia virus (ISAV). Significant outcomes of molecular epidemiological studies include:Improved taxonomic classification of viruses. A better understanding of the natural distribution of viruses. An improved understanding of the origins of viral pathogens in aquaculture. An improved understanding of the risks of translocation of pathogens outwith their natural host range. An increased ability to trace the source of new disease outbreaks. Development of a basis for ensuring development of appropriate diagnostic tools. An ability to classify isolates and thus target future research aimed at better understanding biological function. While molecular epidemiological studies have no doubt already made a significant contribution in these areas, the advent of new technologies such as pyrosequencing heralds a quantum leap in the ability to generate descriptive molecular sequence data. The ability of molecular epidemiology to fulfil its potential to translate complex disease pathways into relevant fish health policy is thus unlikely to be limited by the generation of descriptive molecular markers. More likely, full realisation of the potential to better explain viral transmission pathways will be dependent on the ability to assimilate

  15. Water system virus detection

    NASA Technical Reports Server (NTRS)

    Fraser, A. S.; Wells, A. F.; Tenoso, H. J.

    1975-01-01

    A monitoring system developed to test the capability of a water recovery system to reject the passage of viruses into the recovered water is described. A nonpathogenic marker virus, bacteriophage F2, is fed into the process stream before the recovery unit and the reclaimed water is assayed for its presence. Detection of the marker virus consists of two major components, concentration and isolation of the marker virus, and detection of the marker virus. The concentration system involves adsorption of virus to cellulose acetate filters in the presence of trivalent cations and low pH with subsequent desorption of the virus using volumes of high pH buffer. The detection of the virus is performed by a passive immune agglutination test utilizing specially prepared polystyrene particles. An engineering preliminary design was performed as a parallel effort to the laboratory development of the marker virus test system. Engineering schematics and drawings of a fully functional laboratory prototype capable of zero-G operation are presented. The instrument consists of reagent pump/metering system, reagent storage containers, a filter concentrator, an incubation/detector system, and an electronic readout and control system.

  16. [Zika virus epidemic].

    PubMed

    Kronborg, Gitte; Fomsgaard, Anders

    2016-03-21

    Zika virus is endemic in several parts of the world. February 1, 2016 Zika virus was declared a public health emergency by the WHO. This declaration is mainly due to a convincing association between Zika virus infection during pregnancy and birth defects, like microcephaly, among some of the newborns. Imported cases of Zika virus infection to North America, Europe and Denmark have been described. The infection in itself is mild and self-limiting. The available diagnostic methods are under development, validation and evaluation. In Denmark, some promising diagnostics are available at Statens Serum Institut.

  17. Oral immunization of rainbow trout to infectious pancreatic necrosis virus (Ipnv) induces different immune gene expression profiles in head kidney and pyloric ceca.

    PubMed

    Ballesteros, Natalia A; Saint-Jean, Sylvia S Rodriguez; Encinas, Paloma A; Perez-Prieto, Sara I; Coll, Julio M

    2012-08-01

    Induction of neutralizing antibodies and protection by oral vaccination with DNA-alginates of rainbow trout Oncorhynchus mykiss against infectious pancreatic necrosis virus (IPNV) was recently reported. Because orally induced immune response transcript gene profiles had not been described yet neither in fish, nor after IPNV vaccination, we studied them in head kidney (an immune response internal organ) and a vaccine entry tissue (pyloric ceca). By using an oligo microarray enriched in immune-related genes validated by RTqPCR, the number of increased transcripts in head kidney was higher than in pyloric ceca while the number of decreased transcripts was higher in pyloric ceca than in head kidney. Confirming previous reports on intramuscular DNA vaccination or viral infection, mx genes increased their transcription in head kidney. Other transcript responses such as those corresponding to interferons, their receptors and induced proteins (n=91 genes), VHSV-induced genes (n=25), macrophage-related genes (n=125), complement component genes (n=176), toll-like receptors (n=31), tumor necrosis factors (n=32), chemokines and their receptors (n=121), interleukines and their receptors (n=119), antimicrobial peptides (n=59), and cluster differentiation antigens (n=58) showed a contrasting and often complementary behavior when head kidney and pyloric ceca were compared. For instance, classical complement component transcripts increased in head kidney while only alternative pathway transcripts increased in pyloric ceca, different β-defensins increased in head kidney but remained constant in pyloric ceca. The identification of new gene markers on head kidney/pyloric ceca could be used to follow up and/or to improve immunity during fish oral vaccination.

  18. Equine Arteritis Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    03. Nidovirales : 03.004. Arteriviridae : 03.004.0. {03.004.0. unknown} : 03.004.0.01. Arterivirus : 03.004.0.01.001. Equine arteritis virus will be published online. The article details the phenotypic and genotypic makeup of equine arteritis virus (EAV), and summarizes its biological properties....

  19. Virus separation using membranes.

    PubMed

    Grein, Tanja A; Michalsky, Ronald; Czermak, Peter

    2014-01-01

    Industrial manufacturing of cell culture-derived viruses or virus-like particles for gene therapy or vaccine production are complex multistep processes. In addition to the bioreactor, such processes require a multitude of downstream unit operations for product separation, concentration, or purification. Similarly, before a biopharmaceutical product can enter the market, removal or inactivation of potential viral contamination has to be demonstrated. Given the complexity of biological solutions and the high standards on composition and purity of biopharmaceuticals, downstream processing is the bottleneck in many biotechnological production trains. Membrane-based filtration can be an economically attractive and efficient technology for virus separation. Viral clearance, for instance, of up to seven orders of magnitude has been reported for state of the art polymeric membranes under best conditions.This chapter summarizes the fundamentals of virus ultrafiltration, diafiltration, or purification with adsorptive membranes. In lieu of an impractical universally applicable protocol for virus filtration, application of these principles is demonstrated with two examples. The chapter provides detailed methods for production, concentration, purification, and removal of a rod-shaped baculovirus (Autographa californica M nucleopolyhedrovirus, about 40 × 300 nm in size, a potential vector for gene therapy, and an industrially important protein expression system) or a spherical parvovirus (minute virus of mice, 22-26 nm in size, a model virus for virus clearance validation studies).

  20. Papaya Ringspot Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The term papaya ringspot virus (PRSV) was coined by Jensen in 1949, to describe a papaya disease in Hawaii. Later work showed that diseases such as papaya mosaic and watermelon mosaic virus-1 were caused by PRSV. The primary host range of PRSV is papaya and cucurbits, with Chenopium amaranticolor ...

  1. Positive reinforcement for viruses

    PubMed Central

    Vigant, Frederic; Jung, Michael; Lee, Benhur

    2010-01-01

    Summary Virus-cell membrane fusion requires a critical transition from positive to negative membrane curvature. St. Vincent et al., in PNAS (St Vincent, et al., 2010), designed a class of antivirals that targets this transition. These Rigid Amphipathic Fusion Inhibitors are active against an array of enveloped viruses. PMID:21035726

  2. Positive reinforcement for viruses.

    PubMed

    Vigant, Frederic; Jung, Michael; Lee, Benhur

    2010-10-29

    Virus-cell membrane fusion requires a critical transition from positive to negative membrane curvature. St. Vincent et al. (2010), in PNAS, designed a class of antivirals that targets this transition. These rigid amphipathic fusion inhibitors are active against an array of enveloped viruses.

  3. Rift Valley Fever Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rift Valley fever virus (RVFV) is a mosquito-transmitted virus or arbovirus that is endemic in sub-Saharan Africa. In the last decade, Rift Valley fever (RVF) outbreaks have resulted in loss of human and animal life, as well as had significant economic impact. The disease in livestock is primarily a...

  4. Papaya ringspot virus (Potyviridae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Papaya ringspot virus, a member of the family Potyviridae, is single stranded RNA plant virus with a monocistronic genome of about 10,326 nucleotides that is expressed via a large polyprotein subsequently cleaved into functional proteins. It causes severe damage on cucurbit crops such as squash and...

  5. Zika Virus Disease.

    PubMed

    Slenczka, Werner

    2016-06-01

    The history of Zika virus disease serves as a paradigm of a typical emerging viral infection. Zika virus disease, a mosquito-borne flavivirus, was first isolated in 1947 in the Zika forest of Uganda. The same virus was also isolated from jungle-dwelling mosquitoes (Aedes [Stegomyia] africanus). In many areas of Africa and South Asia human infections with Zika virus were detected by both serology and virus isolation. About 80% of infections are asymptomatic, and in 20% a mostly mild disease with fever, rash, arthralgia, and conjunctivitis may occur. Fetal infections with malformations were not recorded in Africa or Asia. Zika virus was imported to northern Brazil possibly during the world soccer championship that was hosted by Brazil in June through July 2014. A cluster of severe fetal malformations with microcephaly and ocular defects was noted in 2015 in the northeast of Brazil, and intrauterine infections with Zika virus were confirmed. The dramatic change in Zika virus pathogenicity upon its introduction to Brazil has remained an enigma.

  6. Zika Virus and Pregnancy.

    PubMed

    Stagg, Denise; Hurst, Helen M

    2016-01-01

    Recent outbreaks of Zika virus and reports linking infection in pregnant women with microcephaly in newborns have caused concern worldwide. Information has been evolving rapidly. Nurses and other clinicians, especially those who work with women of childbearing age, play a pivotal role in disseminating accurate information and identifying potential cases of Zika virus infection.

  7. Zika Virus and Pregnancy.

    PubMed

    Stagg, Denise; Hurst, Helen M

    2016-01-01

    Recent outbreaks of Zika virus and reports linking infection in pregnant women with microcephaly in newborns have caused concern worldwide. Information has been evolving rapidly. Nurses and other clinicians, especially those who work with women of childbearing age, play a pivotal role in disseminating accurate information and identifying potential cases of Zika virus infection. PMID:27287356

  8. Zika Virus Disease.

    PubMed

    Slenczka, Werner

    2016-06-01

    The history of Zika virus disease serves as a paradigm of a typical emerging viral infection. Zika virus disease, a mosquito-borne flavivirus, was first isolated in 1947 in the Zika forest of Uganda. The same virus was also isolated from jungle-dwelling mosquitoes (Aedes [Stegomyia] africanus). In many areas of Africa and South Asia human infections with Zika virus were detected by both serology and virus isolation. About 80% of infections are asymptomatic, and in 20% a mostly mild disease with fever, rash, arthralgia, and conjunctivitis may occur. Fetal infections with malformations were not recorded in Africa or Asia. Zika virus was imported to northern Brazil possibly during the world soccer championship that was hosted by Brazil in June through July 2014. A cluster of severe fetal malformations with microcephaly and ocular defects was noted in 2015 in the northeast of Brazil, and intrauterine infections with Zika virus were confirmed. The dramatic change in Zika virus pathogenicity upon its introduction to Brazil has remained an enigma. PMID:27337468

  9. Influenza A virus reassortment.

    PubMed

    Steel, John; Lowen, Anice C

    2014-01-01

    Reassortment is the process by which influenza viruses swap gene segments. This genetic exchange is possible due to the segmented nature of the viral genome and occurs when two differing influenza viruses co-infect a cell. The viral diversity generated through reassortment is vast and plays an important role in the evolution of influenza viruses. Herein we review recent insights into the contribution of reassortment to the natural history and epidemiology of influenza A viruses, gained through population scale phylogenic analyses. We describe methods currently used to study reassortment in the laboratory, and we summarize recent progress made using these experimental approaches to further our understanding of influenza virus reassortment and the contexts in which it occurs.

  10. Respiratory viruses and children.

    PubMed

    Heikkinen, Terho

    2016-07-01

    Respiratory viruses place a great disease burden especially on the youngest children in terms of high rates of infection, bacterial complications and hospitalizations. In developing countries, some viral infections are even associated with substantial mortality in children. The interaction between viruses and bacteria is probably much more common and clinically significant than previously understood. Respiratory viruses frequently initiate the cascade of events that ultimately leads to bacterial infection. Effective antiviral agents can substantially shorten the duration of the viral illness and prevent the development of bacterial complications. Viral vaccines have the potential to not only prevent the viral infection but also decrease the incidence of bacterial complications. At present, antivirals and vaccines are only available against influenza viruses, but new vaccines and antivirals against other viruses, especially for RSV, are being developed. PMID:27177731

  11. Respiratory viruses and children.

    PubMed

    Heikkinen, Terho

    2016-07-01

    Respiratory viruses place a great disease burden especially on the youngest children in terms of high rates of infection, bacterial complications and hospitalizations. In developing countries, some viral infections are even associated with substantial mortality in children. The interaction between viruses and bacteria is probably much more common and clinically significant than previously understood. Respiratory viruses frequently initiate the cascade of events that ultimately leads to bacterial infection. Effective antiviral agents can substantially shorten the duration of the viral illness and prevent the development of bacterial complications. Viral vaccines have the potential to not only prevent the viral infection but also decrease the incidence of bacterial complications. At present, antivirals and vaccines are only available against influenza viruses, but new vaccines and antivirals against other viruses, especially for RSV, are being developed.

  12. Akabane virus infection.

    PubMed

    Kirkland, P D

    2015-08-01

    Akabane virus is a Culicoides-borne orthobunyavirus that is teratogenic to the fetus of cattle and small ruminant species. Depending upon the stage of gestation atwhich infection occurs, and the length of gestation of the mammalian host, a range of congenital defects may be observed. The developing central nervous system is usually the most severely affected, with hydranencephaly and arthrogryposis most frequently observed. Less commonly, some strains of Akabane virus can cause encephalitis in the neonate or, rarely, adult cattle. Akabane viruses are known to be widespread in temperate and tropical regions of Australia, Southeast Asia, the Middle East and some African countries. Disease is infrequently observed in regions where this virus is endemic and the presence of the virus remains unrecognised in the absence of serological surveillance. In some Asian countries, vaccines are used to minimise the occurrence of disease. PMID:26601444

  13. Infectious Viral Quantification of Chikungunya Virus-Virus Plaque Assay.

    PubMed

    Kaur, Parveen; Lee, Regina Ching Hua; Chu, Justin Jang Hann

    2016-01-01

    The plaque assay is an essential method for quantification of infectious virus titer. Cells infected with virus particles are overlaid with a viscous substrate. A suitable incubation period results in the formation of plaques, which can be fixed and stained for visualization. Here, we describe a method for measuring Chikungunya virus (CHIKV) titers via virus plaque assays.

  14. Virus discovery and recent insights into virus diversity in arthropods.

    PubMed

    Junglen, Sandra; Drosten, Christian

    2013-08-01

    Recent studies on virus discovery have focused mainly on mammalian and avian viruses. Arbovirology with its long tradition of ecologically oriented investigation is now catching up, with important novel insights into the diversity of arthropod-associated viruses. Recent discoveries include taxonomically outlying viruses within the families Flaviviridae, Togaviridae, and Bunyaviridae, and even novel virus families within the order Nidovirales. However, the current focusing of studies on blood-feeding arthropods has restricted the range of arthropod hosts analyzed for viruses so far. Future investigations should include species from other arthropod taxa than Ixodita, Culicidae and Phlebotominae in order to shed light on the true diversity of arthropod viruses.

  15. Realms of the Viruses Online

    ERIC Educational Resources Information Center

    Liu, Dennis

    2007-01-01

    Viruses have evolved strategies for infecting all taxa, but most viruses are highly specific about their cellular host. In humans, viruses cause diverse diseases, from chronic but benign warts, to acute and deadly hemorrhagic fever. Viruses have entertaining names like Zucchini Yellow Mosaic, Semliki Forest, Coxsackie, and the original terminator,…

  16. Tembusu Virus in Ducks, China

    PubMed Central

    Cao, Zhenzhen; Zhang, Cun; Liu, Yuehuan; Ye, Weicheng; Han, Jingwen; Ma, Guoming; Zhang, Dongdong; Xu, Feng; Gao, Xuhui; Tang, Yi; Shi, Shaohua; Wan, Chunhe; Zhang, Chen; He, Bin; Yang, Mengjie; Lu, Xinhao; Huang, Yu; Diao, Youxiang; Ma, Xuejun

    2011-01-01

    In China in 2010, a disease outbreak in egg-laying ducks was associated with a flavivirus. The virus was isolated and partially sequenced. The isolate exhibited 87%–91% identity with strains of Tembusu virus, a mosquito-borne flavivirus of the Ntaya virus group. These findings demonstrate emergence of Tembusu virus in ducks. PMID:22000358

  17. Postmortem Stability of Ebola Virus

    PubMed Central

    Prescott, Joseph; Bushmaker, Trenton; Fischer, Robert; Miazgowicz, Kerri; Judson, Seth

    2015-01-01

    The ongoing Ebola virus outbreak in West Africa has highlighted questions regarding stability of the virus and detection of RNA from corpses. We used Ebola virus–infected macaques to model humans who died of Ebola virus disease. Viable virus was isolated <7 days posteuthanasia; viral RNA was detectable for 10 weeks. PMID:25897646

  18. Virus-PEDOT Biocomposite Films

    PubMed Central

    Donavan, Keith C.; Arter, Jessica A.

    2012-01-01

    Virus-poly(3,4-ethylenedioxythiophene) (virus-PEDOT) biocomposite films are prepared by electropolymerizing 3,4-ethylenedioxythiophene (EDOT) in aqueous electrolytes containing 12 mM LiClO4 and the bacteriophage M13. The concentration of virus in these solutions, [virus]soln, is varied from 3 nM to 15 nM. A quartz crystal microbalance is used to directly measure the total mass of the biocomposite film during its electrodeposition. In combination with a measurement of the electrodeposition charge, the mass of the virus incorporated into the film is calculated. These data show that concentration of the M13 within the electropolymerized film, [virus]film, increases linearly with [virus]soln. The incorporation of virus particles into the PEDOT film from solution is efficient, resulting in a concentration ratio: [virus]film:[virus]soln ≈450. Virus incorporation into the PEDOT causes roughening of the film topography that is observed using scanning electron microscopy and atomic force microscopy (AFM). The electrical conductivity of the virus-PEDOT film, measured perpendicular to the plane of the film using conductive tip AFM, decreases linearly with virus loading, from 270 μS/cm for pure PE-DOT films to 50 μS/cm for films containing 100 μM virus. The presence on the virus surface of displayed affinity peptides did not significantly influence the efficiency of incorporation into virus-PEDOT biocomposite films. PMID:22856875

  19. A Virus in Turbo Pascal.

    ERIC Educational Resources Information Center

    Teleky, Heidi Ann; And Others

    1993-01-01

    Addresses why the authors feel it is not inappropriate to teach about viruses in the how-to, hands-on fashion. Identifies the special features of Turbo Pascal that have to be used for the creation of an effective virus. Defines virus, derives its structure, and from this structure is derived the implemented virus. (PR)

  20. Computer Viruses: Pathology and Detection.

    ERIC Educational Resources Information Center

    Maxwell, John R.; Lamon, William E.

    1992-01-01

    Explains how computer viruses were originally created, how a computer can become infected by a virus, how viruses operate, symptoms that indicate a computer is infected, how to detect and remove viruses, and how to prevent a reinfection. A sidebar lists eight antivirus resources. (four references) (LRW)

  1. DNA vaccines for aquacultured fish.

    PubMed

    Lorenzen, N; LaPatra, S E

    2005-04-01

    Deoxyribonucleic acid (DNA) vaccination is based on the administration of the gene encoding the vaccine antigen, rather than the antigen itself. Subsequent expression of the antigen by cells in the vaccinated hosts triggers the host immune system. Among the many experimental DNA vaccines tested in various animal species as well as in humans, the vaccines against rhabdovirus diseases in fish have given some of the most promising results. A single intramuscular (IM) injection of microgram amounts of DNA induces rapid and long-lasting protection in farmed salmonids against economically important viruses such as infectious haematopoietic necrosis virus (IHNV) and viral haemorrhagic septicaemia virus (VHSV). DNA vaccines against other types of fish pathogens, however, have so far had limited success. The most efficient delivery route at present is IM injection, and suitable delivery strategies for mass vaccination of small fish have yet to be developed. In terms of safety, no adverse effects in the vaccinated fish have been observed to date. As DNA vaccination is a relatively new technology, various theoretical and long-term safety issues related to the environment and the consumer remain to be fully addressed, although inherently the risks should not be any greater than with the commercial fish vaccines that are currently used. Present classification systems lack clarity in distinguishing DNA-vaccinated animals from genetically modified organisms (GMOs), which could raise issues in terms of licensing and public acceptance of the technology. The potential benefits of DNA vaccines for farmed fish include improved animal welfare, reduced environmental impacts of aquaculture activities, increased food quality and quantity, and more sustainable production. Testing under commercial production conditions has recently been initiated in Canada and Denmark.

  2. Viruses of Chelonia.

    PubMed

    Ahne, W

    1993-02-01

    Viruses occurring in turtles and tortoises are hetergeneous but according to ecologic characteristics and pathogenic properties they can be divided in two major groups: 1. Arboviruses (toga-, flavi-, rhabdo- and bunyaviruses) transmitted by arthropods cause severe diseases in homoiothermic vertebrates. The viruses are of great epidemiological interest in human and veterinary medicine. Chelonia and other reptiles infected by bites of vectors e.g. Aedes, Anopheles, Culex develop cyclic viremia without injury. The ectothermic animals maintain inapparent arbovirus infections during hibernation and they play role as reservoirs for these viruses. 2. Viruses of Chelonia origin (papova-, herpes-, irido- and paramyxoviruses) associated with diseases of infected turtles and tortoises have been described frequently during the last 20 years. Several viruses or virus-like particles could be demonstrated in affected reptiles mainly by electron microscopy. Especially herpesviruses seem to attack Chelonia and epizootics due to infections with these viruses were reported in several reptiles in collections. However, the etiological role of the agents detected is not well documented yet. PMID:8456570

  3. Ocular Tropism of Respiratory Viruses

    PubMed Central

    Rota, Paul A.; Tumpey, Terrence M.

    2013-01-01

    SUMMARY Respiratory viruses (including adenovirus, influenza virus, respiratory syncytial virus, coronavirus, and rhinovirus) cause a broad spectrum of disease in humans, ranging from mild influenza-like symptoms to acute respiratory failure. While species D adenoviruses and subtype H7 influenza viruses are known to possess an ocular tropism, documented human ocular disease has been reported following infection with all principal respiratory viruses. In this review, we describe the anatomical proximity and cellular receptor distribution between ocular and respiratory tissues. All major respiratory viruses and their association with human ocular disease are discussed. Research utilizing in vitro and in vivo models to study the ability of respiratory viruses to use the eye as a portal of entry as well as a primary site of virus replication is highlighted. Identification of shared receptor-binding preferences, host responses, and laboratory modeling protocols among these viruses provides a needed bridge between clinical and laboratory studies of virus tropism. PMID:23471620

  4. Genome of horsepox virus.

    PubMed

    Tulman, E R; Delhon, G; Afonso, C L; Lu, Z; Zsak, L; Sandybaev, N T; Kerembekova, U Z; Zaitsev, V L; Kutish, G F; Rock, D L

    2006-09-01

    Here we present the genomic sequence of horsepox virus (HSPV) isolate MNR-76, an orthopoxvirus (OPV) isolated in 1976 from diseased Mongolian horses. The 212-kbp genome contained 7.5-kbp inverted terminal repeats and lacked extensive terminal tandem repetition. HSPV contained 236 open reading frames (ORFs) with similarity to those in other OPVs, with those in the central 100-kbp region most conserved relative to other OPVs. Phylogenetic analysis of the conserved region indicated that HSPV is closely related to sequenced isolates of vaccinia virus (VACV) and rabbitpox virus, clearly grouping together these VACV-like viruses. Fifty-four HSPV ORFs likely represented fragments of 25 orthologous OPV genes, including in the central region the only known fragmented form of an OPV ribonucleotide reductase large subunit gene. In terminal genomic regions, HSPV lacked full-length homologues of genes variably fragmented in other VACV-like viruses but was unique in fragmentation of the homologue of VACV strain Copenhagen B6R, a gene intact in other known VACV-like viruses. Notably, HSPV contained in terminal genomic regions 17 kbp of OPV-like sequence absent in known VACV-like viruses, including fragments of genes intact in other OPVs and approximately 1.4 kb of sequence present only in cowpox virus (CPXV). HSPV also contained seven full-length genes fragmented or missing in other VACV-like viruses, including intact homologues of the CPXV strain GRI-90 D2L/I4R CrmB and D13L CD30-like tumor necrosis factor receptors, D3L/I3R and C1L ankyrin repeat proteins, B19R kelch-like protein, D7L BTB/POZ domain protein, and B22R variola virus B22R-like protein. These results indicated that HSPV contains unique genomic features likely contributing to a unique virulence/host range phenotype. They also indicated that while closely related to known VACV-like viruses, HSPV contains additional, potentially ancestral sequences absent in other VACV-like viruses.

  5. Viruses in reptiles

    PubMed Central

    2011-01-01

    The etiology of reptilian viral diseases can be attributed to a wide range of viruses occurring across different genera and families. Thirty to forty years ago, studies of viruses in reptiles focused mainly on the zoonotic potential of arboviruses in reptiles and much effort went into surveys and challenge trials of a range of reptiles with eastern and western equine encephalitis as well as Japanese encephalitis viruses. In the past decade, outbreaks of infection with West Nile virus in human populations and in farmed alligators in the USA has seen the research emphasis placed on the issue of reptiles, particularly crocodiles and alligators, being susceptible to, and reservoirs for, this serious zoonotic disease. Although there are many recognised reptilian viruses, the evidence for those being primary pathogens is relatively limited. Transmission studies establishing pathogenicity and cofactors are likewise scarce, possibly due to the relatively low commercial importance of reptiles, difficulties with the availability of animals and permits for statistically sound experiments, difficulties with housing of reptiles in an experimental setting or the inability to propagate some viruses in cell culture to sufficient titres for transmission studies. Viruses as causes of direct loss of threatened species, such as the chelonid fibropapilloma associated herpesvirus and ranaviruses in farmed and wild tortoises and turtles, have re-focused attention back to the characterisation of the viruses as well as diagnosis and pathogenesis in the host itself. 1. Introduction 2. Methods for working with reptilian viruses 3. Reptilian viruses described by virus families 3.1. Herpesviridae 3.2. Iridoviridae 3.2.1 Ranavirus 3.2.2 Erythrocytic virus 3.2.3 Iridovirus 3.3. Poxviridae 3.4. Adenoviridae 3.5. Papillomaviridae 3.6. Parvoviridae 3.7. Reoviridae 3.8. Retroviridae and inclusion body disease of Boid snakes 3.9. Arboviruses 3.9.1. Flaviviridae 3.9.2. Togaviridae 3.10. Caliciviridae

  6. [Ebola virus disease].

    PubMed

    Nazimek, Katarzyna; Bociaga-Jasik, Monika; Bryniarski, Krzysztof; Gałas, Aleksander; Garlicki, Aleksander; Gawda, Anna; Gawlik, Grzegorz; Gil, Krzysztof; Kosz-Vnenchak, Magdalena; Mrozek-Budzyn, Dorota; Olszanecki, Rafał; Piatek, Anna; Zawilińska, Barbara; Marcinkiewicz, Janusz

    2014-01-01

    Ebola is one of the most virulent zoonotic RNA viruses causing in humans haemorrhagic fever with fatality ratio reaching 90%. During the outbreak of 2014 the number of deaths exceeded 8.000. The "imported" cases reported in Western Europe and USA highlighted the extreme risk of Ebola virus spreading outside the African countries. Thus, haemorrhagic fever outbreak is an international epidemiological problem, also due to the lack of approved prevention and therapeutic strategies. The editorial review article briefly summarizes current knowledge on Ebola virus disease epidemiology, etiology, pathogenesis, clinical presentation, diagnosis as well as possible prevention and treatment.

  7. Hepatitis B virus (image)

    MedlinePlus

    Hepatitis B is also known as serum hepatitis and is spread through blood and sexual contact. It is ... population. This photograph is an electronmicroscopic image of hepatitis B virus particles. (Image courtesy of the Centers for ...

  8. [Zika, a neurotropic virus?].

    PubMed

    Del Carpio-Orantes, Luis

    2016-01-01

    In this paper, the neurotropism potential Zika virus is discussed, by comparison with viruses both RNA and DNA are neurotropic known, also it is said that compared with the new viruses that have affected the Americas, as the chikungunya, Zika has shown great affinity by brain tissue, manifested by a high incidence of acute neurological conditions, such as Guillain-Barré syndrome, among others, as well as the reported incidence of microcephaly that is abnormally high compared with the previous incidence, which, in a stillborn subject necropsied significant alterations demonstrated in brain tissue, identifying viral material and live virus in the fetoplacental complex, and demonstrating the impact both white matter and gray matter as well as basal ganglia, corpus callosum, ventricles and spinal cord, which could explain the microcephaly that concerns him. Although not a direct cause-effect relationship is demonstrated, however current evidence supports that relationship, hoping to be supported scientifically.

  9. The dengue viruses.

    PubMed Central

    Henchal, E A; Putnak, J R

    1990-01-01

    Dengue, a major public health problem throughout subtropical and tropical regions, is an acute infectious disease characterized by biphasic fever, headache, pain in various parts of the body, prostration, rash, lymphadenopathy, and leukopenia. In more severe or complicated dengue, patients present with a severe febrile illness characterized by abnormalities of hemostasis and increased vascular permeability, which in some instances results in a hypovolemic shock. Four distinct serotypes of the dengue virus (dengue-1, dengue-2, dengue-3, and dengue-4) exist, with numerous virus strains found worldwide. Molecular cloning methods have led to a greater understanding of the structure of the RNA genome and definition of virus-specific structural and nonstructural proteins. Progress towards producing safe, effective dengue virus vaccines, a goal for over 45 years, has been made. Images PMID:2224837

  10. VIRUS instrument enclosures

    NASA Astrophysics Data System (ADS)

    Prochaska, T.; Allen, R.; Mondrik, N.; Rheault, J. P.; Sauseda, M.; Boster, E.; James, M.; Rodriguez-Patino, M.; Torres, G.; Ham, J.; Cook, E.; Baker, D.; DePoy, Darren L.; Marshall, Jennifer L.; Hill, G. J.; Perry, D.; Savage, R. D.; Good, J. M.; Vattiat, Brian L.

    2014-08-01

    The Visible Integral-Field Replicable Unit Spectrograph (VIRUS) instrument will be installed at the Hobby-Eberly Telescope† in the near future. The instrument will be housed in two enclosures that are mounted adjacent to the telescope, via the VIRUS Support Structure (VSS). We have designed the enclosures to support and protect the instrument, to enable servicing of the instrument, and to cool the instrument appropriately while not adversely affecting the dome environment. The system uses simple HVAC air handling techniques in conjunction with thermoelectric and standard glycol heat exchangers to provide efficient heat removal. The enclosures also provide power and data transfer to and from each VIRUS unit, liquid nitrogen cooling to the detectors, and environmental monitoring of the instrument and dome environments. In this paper, we describe the design and fabrication of the VIRUS enclosures and their subsystems.

  11. Respiratory syncytial virus (RSV)

    MedlinePlus

    ... RSV often spreads quickly in crowded households and day care centers. The virus can live for a half ... The following increase the risk for RSV: Attending day care Being near tobacco smoke Having school-aged brothers ...

  12. West Nile Virus

    MedlinePlus

    ... to human beings through their bites. Credit: CDC Biology, Genetics, & Clinical Research NIAID conducts and funds basic and clinical research on WNV biology and viral structure, ways the virus causes human ...

  13. What's West Nile Virus?

    MedlinePlus

    ... is caused by a bite from an infected mosquito that's already carrying the virus, but it's important ... the risk of being bitten by an infected mosquito is greatest from July to early September. But ...

  14. Avoiding Computer Viruses.

    ERIC Educational Resources Information Center

    Rowe, Joyce; And Others

    1989-01-01

    The threat of computer sabotage is a real concern to business teachers and others responsible for academic computer facilities. Teachers can minimize the possibility. Eight suggestions for avoiding computer viruses are given. (JOW)

  15. West Nile Virus

    MedlinePlus

    ... appeared in the United States in 1999. Infected mosquitoes spread the virus that causes it. People who ... barrels Stay indoors between dusk and dawn, when mosquitoes are most active Use screens on windows to ...

  16. The dengue viruses.

    PubMed

    Henchal, E A; Putnak, J R

    1990-10-01

    Dengue, a major public health problem throughout subtropical and tropical regions, is an acute infectious disease characterized by biphasic fever, headache, pain in various parts of the body, prostration, rash, lymphadenopathy, and leukopenia. In more severe or complicated dengue, patients present with a severe febrile illness characterized by abnormalities of hemostasis and increased vascular permeability, which in some instances results in a hypovolemic shock. Four distinct serotypes of the dengue virus (dengue-1, dengue-2, dengue-3, and dengue-4) exist, with numerous virus strains found worldwide. Molecular cloning methods have led to a greater understanding of the structure of the RNA genome and definition of virus-specific structural and nonstructural proteins. Progress towards producing safe, effective dengue virus vaccines, a goal for over 45 years, has been made. PMID:2224837

  17. Viruses and Multiple Sclerosis

    PubMed Central

    Virtanen, Jussi Oskari; Jacobson, Steve

    2016-01-01

    Multiple sclerosis (MS) is a heterogeneous disease that develops as an interplay between the immune system and environmental stimuli in genetically susceptible individuals. There is increasing evidence that viruses may play a role in MS pathogenesis acting as these environmental triggers. However, it is not known if any single virus is causal, or rather several viruses can act as triggers in disease development. Here, we review the association of different viruses to MS with an emphasis on two herpesviruses, Epstein-Barr virus (EBV) and human herpesvirus 6 (HHV-6). These two agents have generated the most impact during recent years as possible co-factors in MS disease development. The strongest argument for association of EBV with MS comes from the link between symptomatic infectious mononucleosis and MS and from seroepidemiological studies. In contrast to EBV, HHV-6 has been found significantly more often in MS plaques than in MS normal appearing white matter or non-MS brains and HHV-6 re-activation has been reported during MS clinical relapses. In this review we also suggest new strategies, including the development of new infectious animal models of MS and antiviral MS clinical trials, to elucidate roles of different viruses in the pathogenesis of this disease. Furthermore, we introduce the idea of using unbiased sequence-independent pathogen discovery methodologies, such as next generation sequencing, to study MS brain tissue or body fluids for detection of known viral sequences or potential novel viral agents. PMID:22583435

  18. Human Influenza Virus Infections.

    PubMed

    Peteranderl, Christin; Herold, Susanne; Schmoldt, Carole

    2016-08-01

    Seasonal and pandemic influenza are the two faces of respiratory infections caused by influenza viruses in humans. As seasonal influenza occurs on an annual basis, the circulating virus strains are closely monitored and a yearly updated vaccination is provided, especially to identified risk populations. Nonetheless, influenza virus infection may result in pneumonia and acute respiratory failure, frequently complicated by bacterial coinfection. Pandemics are, in contrary, unexpected rare events related to the emergence of a reassorted human-pathogenic influenza A virus (IAV) strains that often causes increased morbidity and spreads extremely rapidly in the immunologically naive human population, with huge clinical and economic impact. Accordingly, particular efforts are made to advance our knowledge on the disease biology and pathology and recent studies have brought new insights into IAV adaptation mechanisms to the human host, as well as into the key players in disease pathogenesis on the host side. Current antiviral strategies are only efficient at the early stages of the disease and are challenged by the genomic instability of the virus, highlighting the need for novel antiviral therapies targeting the pulmonary host response to improve viral clearance, reduce the risk of bacterial coinfection, and prevent or attenuate acute lung injury. This review article summarizes our current knowledge on the molecular basis of influenza infection and disease progression, the key players in pathogenesis driving severe disease and progression to lung failure, as well as available and envisioned prevention and treatment strategies against influenza virus infection. PMID:27486731

  19. Virus templated metallic nanoparticles

    NASA Astrophysics Data System (ADS)

    Aljabali, Alaa A. A.; Barclay, J. Elaine; Lomonossoff, George P.; Evans, David J.

    2010-12-01

    Plant viruses are considered as nanobuilding blocks that can be used as synthons or templates for novel materials. Cowpea mosaic virus (CPMV) particles have been shown to template the fabrication of metallic nanoparticles by an electroless deposition metallization process. Palladium ions were electrostatically bound to the virus capsid and, when reduced, acted as nucleation sites for the subsequent metal deposition from solution. The method, although simple, produced highly monodisperse metallic nanoparticles with a diameter of ca. <=35 nm. CPMV-templated particles were prepared with cobalt, nickel, iron, platinum, cobalt-platinum and nickel-iron.Plant viruses are considered as nanobuilding blocks that can be used as synthons or templates for novel materials. Cowpea mosaic virus (CPMV) particles have been shown to template the fabrication of metallic nanoparticles by an electroless deposition metallization process. Palladium ions were electrostatically bound to the virus capsid and, when reduced, acted as nucleation sites for the subsequent metal deposition from solution. The method, although simple, produced highly monodisperse metallic nanoparticles with a diameter of ca. <=35 nm. CPMV-templated particles were prepared with cobalt, nickel, iron, platinum, cobalt-platinum and nickel-iron. Electronic supplementary information (ESI) available: Additional experimental detail, agarose gel electrophoresis results, energy dispersive X-ray spectra, ζ-potential measurements, dynamic light scattering data, nanoparticle tracking analysis and an atomic force microscopy image of Ni-CPMV. See DOI: 10.1039/c0nr00525h

  20. Human Influenza Virus Infections.

    PubMed

    Peteranderl, Christin; Herold, Susanne; Schmoldt, Carole

    2016-08-01

    Seasonal and pandemic influenza are the two faces of respiratory infections caused by influenza viruses in humans. As seasonal influenza occurs on an annual basis, the circulating virus strains are closely monitored and a yearly updated vaccination is provided, especially to identified risk populations. Nonetheless, influenza virus infection may result in pneumonia and acute respiratory failure, frequently complicated by bacterial coinfection. Pandemics are, in contrary, unexpected rare events related to the emergence of a reassorted human-pathogenic influenza A virus (IAV) strains that often causes increased morbidity and spreads extremely rapidly in the immunologically naive human population, with huge clinical and economic impact. Accordingly, particular efforts are made to advance our knowledge on the disease biology and pathology and recent studies have brought new insights into IAV adaptation mechanisms to the human host, as well as into the key players in disease pathogenesis on the host side. Current antiviral strategies are only efficient at the early stages of the disease and are challenged by the genomic instability of the virus, highlighting the need for novel antiviral therapies targeting the pulmonary host response to improve viral clearance, reduce the risk of bacterial coinfection, and prevent or attenuate acute lung injury. This review article summarizes our current knowledge on the molecular basis of influenza infection and disease progression, the key players in pathogenesis driving severe disease and progression to lung failure, as well as available and envisioned prevention and treatment strategies against influenza virus infection.

  1. Transmission of influenza A viruses.

    PubMed

    Neumann, Gabriele; Kawaoka, Yoshihiro

    2015-05-01

    Influenza A viruses cause respiratory infections that range from asymptomatic to deadly in humans. Widespread outbreaks (pandemics) are attributable to 'novel' viruses that possess a viral hemagglutinin (HA) gene to which humans lack immunity. After a pandemic, these novel viruses form stable virus lineages in humans and circulate until they are replaced by other novel viruses. The factors and mechanisms that facilitate virus transmission among hosts and the establishment of novel lineages are not completely understood, but the HA and basic polymerase 2 (PB2) proteins are thought to play essential roles in these processes by enabling avian influenza viruses to infect mammals and replicate efficiently in their new host. Here, we summarize our current knowledge of the contributions of HA, PB2, and other viral components to virus transmission and the formation of new virus lineages. PMID:25812763

  2. Transmission of Influenza A Viruses

    PubMed Central

    Neumann, Gabriele; Kawaoka, Yoshihiro

    2015-01-01

    Influenza A viruses cause respiratory infections that range from asymptomatic to deadly in humans. Widespread outbreaks (pandemics) are attributable to ‘novel’ viruses that possess a viral hemagglutinin (HA) gene to which humans lack immunity. After a pandemic, these novel viruses form stable virus lineages in humans and circulate until they are replaced by other novel viruses. The factors and mechanisms that facilitate virus transmission among hosts and the establishment of novel lineages are not completely understood, but the HA and basic polymerase 2 (PB2) proteins are thought to play essential roles in these processes by enabling avian influenza viruses to infect mammals and replicate efficiently in their new host. Here, we summarize our current knowledge of the contributions of HA, PB2, and other viral components to virus transmission and the formation of new virus lineages. PMID:25812763

  3. Smaller Fleas: Viruses of Microorganisms

    PubMed Central

    Hyman, Paul; Abedon, Stephen T.

    2012-01-01

    Life forms can be roughly differentiated into those that are microscopic versus those that are not as well as those that are multicellular and those that, instead, are unicellular. Cellular organisms seem generally able to host viruses, and this propensity carries over to those that are both microscopic and less than truly multicellular. These viruses of microorganisms, or VoMs, in fact exist as the world's most abundant somewhat autonomous genetic entities and include the viruses of domain Bacteria (bacteriophages), the viruses of domain Archaea (archaeal viruses), the viruses of protists, the viruses of microscopic fungi such as yeasts (mycoviruses), and even the viruses of other viruses (satellite viruses). In this paper we provide an introduction to the concept of viruses of microorganisms, a.k.a., viruses of microbes. We provide broad discussion particularly of VoM diversity. VoM diversity currently spans, in total, at least three-dozen virus families. This is roughly ten families per category—bacterial, archaeal, fungal, and protist—with some virus families infecting more than one of these microorganism major taxa. Such estimations, however, will vary with further discovery and taxon assignment and also are dependent upon what forms of life one includes among microorganisms. PMID:24278736

  4. Smaller fleas: viruses of microorganisms.

    PubMed

    Hyman, Paul; Abedon, Stephen T

    2012-01-01

    Life forms can be roughly differentiated into those that are microscopic versus those that are not as well as those that are multicellular and those that, instead, are unicellular. Cellular organisms seem generally able to host viruses, and this propensity carries over to those that are both microscopic and less than truly multicellular. These viruses of microorganisms, or VoMs, in fact exist as the world's most abundant somewhat autonomous genetic entities and include the viruses of domain Bacteria (bacteriophages), the viruses of domain Archaea (archaeal viruses), the viruses of protists, the viruses of microscopic fungi such as yeasts (mycoviruses), and even the viruses of other viruses (satellite viruses). In this paper we provide an introduction to the concept of viruses of microorganisms, a.k.a., viruses of microbes. We provide broad discussion particularly of VoM diversity. VoM diversity currently spans, in total, at least three-dozen virus families. This is roughly ten families per category-bacterial, archaeal, fungal, and protist-with some virus families infecting more than one of these microorganism major taxa. Such estimations, however, will vary with further discovery and taxon assignment and also are dependent upon what forms of life one includes among microorganisms.

  5. [Zika virus infection during pregnancy].

    PubMed

    Picone, O; Vauloup-Fellous, C; D'Ortenzio, E; Huissoud, C; Carles, G; Benachi, A; Faye, A; Luton, D; Paty, M-C; Ayoubi, J-M; Yazdanpanah, Y; Mandelbrot, L; Matheron, S

    2016-05-01

    A Zika virus epidemic is currently ongoing in the Americas. This virus is linked to congenital infections with potential severe neurodevelopmental dysfunction. However, incidence of fetal infection and whether this virus is responsible of other fetal complications are still unknown. National and international public health authorities recommend caution and several prevention measures. Declaration of Zika virus infection is now mandatory in France. Given the available knowledge on Zika virus, we suggest here a review of the current recommendations for management of pregnancy in case of suspicious or infection by Zika virus in a pregnant woman. PMID:27079865

  6. [Zika virus infection during pregnancy].

    PubMed

    Picone, O; Vauloup-Fellous, C; D'Ortenzio, E; Huissoud, C; Carles, G; Benachi, A; Faye, A; Luton, D; Paty, M-C; Ayoubi, J-M; Yazdanpanah, Y; Mandelbrot, L; Matheron, S

    2016-05-01

    A Zika virus epidemic is currently ongoing in the Americas. This virus is linked to congenital infections with potential severe neurodevelopmental dysfunction. However, incidence of fetal infection and whether this virus is responsible of other fetal complications are still unknown. National and international public health authorities recommend caution and several prevention measures. Declaration of Zika virus infection is now mandatory in France. Given the available knowledge on Zika virus, we suggest here a review of the current recommendations for management of pregnancy in case of suspicious or infection by Zika virus in a pregnant woman.

  7. Recombinant Vaccinia Virus: Immunization against Multiple Pathogens

    NASA Astrophysics Data System (ADS)

    Perkus, Marion E.; Piccini, Antonia; Lipinskas, Bernard R.; Paoletti, Enzo

    1985-09-01

    The coding sequences for the hepatitis B virus surface antigen, the herpes simplex virus glycoprotein D, and the influenza virus hemagglutinin were inserted into a single vaccinia virus genome. Rabbits inoculated intravenously or intradermally with this polyvalent vaccinia virus recombinant produced antibodies reactive to all three authentic foreign antigens. In addition, the feasibility of multiple rounds of vaccination with recombinant vaccinia virus was demonstrated.

  8. Molecular cloning, characterization and expression analysis of peroxiredoxin 6 from disk abalone Haliotis discus discus and the antioxidant activity of its recombinant protein.

    PubMed

    Nikapitiya, Chamilani; De Zoysa, Mahanama; Whang, Ilson; Kim, Choon-Gon; Lee, Youn-Ho; Kim, Sang-Jin; Lee, Jehee

    2009-08-01

    Peroxiredoxins (Prxs) play an important role against various oxidative stresses and intra-cellular signal transduction. Peroxiredoxin 6 (PrxVI) was identified from the disk abalone Haliotis discus discus cDNA library and named HdPrxVI. The full length cDNA of HdPrxVI was 1457 bp with a 654 bp open reading frame (ORF) encoding 218 amino acids. The predicted molecular mass and estimated isoelectric point (pI) of HdPrxVI were 24 kDa and 7.3, respectively. The deduced amino acid sequence demonstrated the greatest degree (72.4%) of identity with Crassostrea gigas PrxVI. The conserved peroxidase catalytic center (42PVCTTE47) with a conserved cysteine residue (Cys44) and a catalytic center for PLA2 activity (27GGSWA31) were observed in the sequence, indicating that it is a member of 1-Cys Prx. Real time PCR results revealed that HdPrxVI mRNA is constitutively expressed in all tissues in a tissue-specific manner. During exposure to haemorrhagic septicaemia virus (VHSV), HdPrxVI mRNA transcription was down-regulated in the gill, suggesting that the abalone responded to the viral infection quickly, and HdPrxVI played a physiological role against virus-induced oxidative stress. The purified recombinant HdPrxVI, together with dithiothreitol (DTT), was shown to scavenge H2O2 in human leukemia THP-1 cells and provided protection against H2O2-induced apoptosis.

  9. Two African viruses serologically and morphologically related to rabies virus.

    PubMed

    Shope, R E; Murphy, F A; Harrison, A K; Causey, O R; Kemp, G E; Simpson, D I; Moore, D L

    1970-11-01

    Lagos bat virus and an isolate from shrews (IbAn 27377), both from Nigeria, were found to be bullet-shaped and to mature intracytoplasmically in association with a distinct matrix. They were related to, but readily distinguishable from, rabies virus and each other by complement fixation and neutralization tests. The three viruses, including rabies, form a subgrouping within the rhabdoviruses. PMID:5530013

  10. Efficient Co-Replication of Defective Novirhabdovirus

    PubMed Central

    Rouxel, Ronan N.; Mérour, Emilie; Biacchesi, Stéphane; Brémont, Michel

    2016-01-01

    We have generated defective Viral Hemorrhagic Septicemia Viruses (VHSV) which express either the green fluorescent protein (GFP) or a far-red fluorescent protein (mKate) by replacing the genes encoding the nucleoprotein N or the polymerase-associated P protein. To recover viable defective viruses, rVHSV-ΔN-Red and rVHSV-ΔP-Green, fish cells were co-transfected with both deleted cDNA VHSV genomes, together with plasmids expressing N, P and L of the RNA-dependent RNA polymerase. After one passage of the transfected cell supernatant, red and green cell foci were observed. Viral titer reached 107 PFU/mL after three passages. Infected cells were always red and green with the very rare event of single red or green cell foci appearing. To clarify our understanding of how such defective viruses could be so efficiently propagated, we investigated whether (i) a recombination event between both defective genomes had occurred, (ii) whether both genomes were co-encapsidated in a single viral particle, and (iii) whether both defective viruses were always replicated together through a complementation phenomenon or even as conglomerate. To address these hypotheses, genome and viral particles have been fully characterized and, thus, allowing us to conclude that rVHSV-ΔN-Red and rVHSV-ΔP-Green are independent viral particles which could propagate only by simultaneously infecting the same cells. PMID:26959049

  11. Efficient Co-Replication of Defective Novirhabdovirus.

    PubMed

    Rouxel, Ronan N; Mérour, Emilie; Biacchesi, Stéphane; Brémont, Michel

    2016-03-01

    We have generated defective Viral Hemorrhagic Septicemia Viruses (VHSV) which express either the green fluorescent protein (GFP) or a far-red fluorescent protein (mKate) by replacing the genes encoding the nucleoprotein N or the polymerase-associated P protein. To recover viable defective viruses, rVHSV-ΔN-Red and rVHSV-ΔP-Green, fish cells were co-transfected with both deleted cDNA VHSV genomes, together with plasmids expressing N, P and L of the RNA-dependent RNA polymerase. After one passage of the transfected cell supernatant, red and green cell foci were observed. Viral titer reached 10⁷ PFU/mL after three passages. Infected cells were always red and green with the very rare event of single red or green cell foci appearing. To clarify our understanding of how such defective viruses could be so efficiently propagated, we investigated whether (i) a recombination event between both defective genomes had occurred, (ii) whether both genomes were co-encapsidated in a single viral particle, and (iii) whether both defective viruses were always replicated together through a complementation phenomenon or even as conglomerate. To address these hypotheses, genome and viral particles have been fully characterized and, thus, allowing us to conclude that rVHSV-ΔN-Red and rVHSV-ΔP-Green are independent viral particles which could propagate only by simultaneously infecting the same cells. PMID:26959049

  12. [Viruses and civilization].

    PubMed

    Chastel, C

    1999-01-01

    A few million years ago, when primates moved from the east African forest to the savannah, they were already infected with endogenous viruses and occultly transmitted them to the prime Homo species. However it was much later with the building of the first large cities in Mesopotamia that interhuman viral transmission began in earnest. Spreading was further enhanced with the organization of the Egyptian, Greek, Roman, and Arab empires around the Mediterranean. Discovery of the New World in 1492 led to an unprecedented clash of civilizations and the destruction of pre-Columbian Indian civilizations. It also led to a rapid spread of viruses across the Atlantic Ocean with the emergence of yellow fever and appearance of smallpox and measles throughout the world. However the greatest opportunities for worldwide viral development have been created by our present, modern civilization. This fact is illustrated by epidemic outbreaks of human immunodeficiency virus, Venezuela hemorrhagic fever, Rift valley fever virus, and monkey pox virus. Close analysis underscores the major role of human intervention in producing these events.

  13. Viruses and Multiple Sclerosis

    PubMed Central

    Owens, Gregory P.; Gilden, Don; Burgoon, Mark P.; Yu, Xiaoli; Bennett, Jeffrey L.

    2012-01-01

    Multiple sclerosis (MS) is a chronic demyelinating disorder of unknown etiology, possibly caused by a virus or virus-triggered immunopathology. The virus might reactivate after years of latency and lyse oligodendrocytes, as in progressive multifocal leukoencephalopathy, or initiate immunopathological demyelination, as in animals infected with Theiler’s murine encephalomyelitis virus or coronaviruses. The argument for a viral cause of MS is supported by epidemiological analyses and studies of MS in identical twins, indicating that disease is acquired. However, the most important evidence is the presence of bands of oligoclonal IgG (OCBs) in MS brain and CSF that persist throughout the lifetime of the patient. OCBs are found almost exclusively in infectious CNS disorders, and antigenic targets of OCBs represent the agent that causes disease. Here, the authors review past attempts to identify an infectious agent in MS brain cells and discuss the promise of using recombinant antibodies generated from clonally expanded plasma cells in brain and CSF to identify disease-relevant antigens. They show how this strategy has been used successfully to analyze antigen specificity in subacute sclerosing panencephalitis, a chronic encephalitis caused by measles virus, and in neuromyelitis optica, a chronic autoimmune demyelinating disease produced by antibodies directed against the aquaporin-4 water channel. PMID:22130640

  14. Viruses and multiple sclerosis.

    PubMed

    Owens, Gregory P; Gilden, Don; Burgoon, Mark P; Yu, Xiaoli; Bennett, Jeffrey L

    2011-12-01

    Multiple sclerosis (MS) is a chronic demyelinating disorder of unknown etiology, possibly caused by a virus or virus-triggered immunopathology. The virus might reactivate after years of latency and lyse oligodendrocytes, as in progressive multifocal leukoencephalopathy, or initiate immunopathological demyelination, as in animals infected with Theiler's murine encephalomyelitis virus or coronaviruses. The argument for a viral cause of MS is supported by epidemiological analyses and studies of MS in identical twins, indicating that disease is acquired. However, the most important evidence is the presence of bands of oligoclonal IgG (OCBs) in MS brain and CSF that persist throughout the lifetime of the patient. OCBs are found almost exclusively in infectious CNS disorders, and antigenic targets of OCBs represent the agent that causes disease. Here, the authors review past attempts to identify an infectious agent in MS brain cells and discuss the promise of using recombinant antibodies generated from clonally expanded plasma cells in brain and CSF to identify disease-relevant antigens. They show how this strategy has been used successfully to analyze antigen specificity in subacute sclerosing panencephalitis, a chronic encephalitis caused by measles virus, and in neuromyelitis optica, a chronic autoimmune demyelinating disease produced by antibodies directed against the aquaporin-4 water channel. PMID:22130640

  15. Attenuation of Vaccinia Virus.

    PubMed

    Yakubitskiy, S N; Kolosova, I V; Maksyutov, R A; Shchelkunov, S N

    2015-01-01

    Since 1980, in the post-smallpox vaccination era the human population has become increasingly susceptible compared to a generation ago to not only the variola (smallpox) virus, but also other zoonotic orthopoxviruses. The need for safer vaccines against orthopoxviruses is even greater now. The Lister vaccine strain (LIVP) of vaccinia virus was used as a parental virus for generating a recombinant 1421ABJCN clone defective in five virulence genes encoding hemagglutinin (A56R), the IFN-γ-binding protein (B8R), thymidine kinase (J2R), the complement-binding protein (C3L), and the Bcl-2-like inhibitor of apoptosis (N1L). We found that disruption of these loci does not affect replication in mammalian cell cultures. The isogenic recombinant strain 1421ABJCN exhibits a reduced inflammatory response and attenuated neurovirulence relative to LIVP. Virus titers of 1421ABJCN were 3 lg lower versus the parent VACV LIVP when administered by the intracerebral route in new-born mice. In a subcutaneous mouse model, 1421ABJCN displayed levels of VACV-neutralizing antibodies comparable to those of LIVP and conferred protective immunity against lethal challenge by the ectromelia virus. The VACV mutant holds promise as a safe live vaccine strain for preventing smallpox and other orthopoxvirus infections. PMID:26798498

  16. [Markers of hepatitis virus].

    PubMed

    Suzuki, Fumitaka

    2008-11-01

    Hepatitis B virus (HBV) and hepatitis C virus (HCV) are the major viruses known to cause viral hepatitis. Serological markers are commonly used as diagnostic and/or prognostic indicators of acute or chronic HBV or HCV infection. The ability to detect HBV DNA in serum has been reported to have prognostic value for the outcome of chronic HBV infection. A rapid and sustained drop in HBV DNA or HCV RNA levels in patients under therapy has been shown to be a predictive factor for a favourable treatment outcome. Various techniques for detecting HBV DNA or HCV RNA have already been described; however, there are various problems with the sensitivity or detection range of those methods. New virus measuring methods have recently been reported and used. The Cobas Taq Man HCV Test is a new method to detect HBV DNA and HCV RNA with higher sensitivity and a broader range of quantitation than conventional methods. Some reports have shown that these methods improve therapy monitoring and the management of HBV or HCV infection. Moreover, hepatitis E virus (HEV) infection has been reported in Japan. The clinical features and viral markers of HEV have also been described. PMID:19086457

  17. Special Issue: Honey Bee Viruses.

    PubMed

    Gisder, Sebastian; Genersch, Elke

    2015-10-01

    Pollination of flowering plants is an important ecosystem service provided by wild insect pollinators and managed honey bees. Hence, losses and declines of pollinating insect species threaten human food security and are of major concern not only for apiculture or agriculture but for human society in general. Honey bee colony losses and bumblebee declines have attracted intensive research interest over the last decade and although the problem is far from being solved we now know that viruses are among the key players of many of these bee losses and bumblebee declines. With this special issue on bee viruses we, therefore, aimed to collect high quality original papers reflecting the current state of bee virus research. To this end, we focused on newly discovered viruses (Lake Sinai viruses, bee macula-like virus), or a so far neglected virus species (Apis mellifera filamentous virus), and cutting edge technologies (mass spectrometry, RNAi approach) applied in the field.

  18. Chlorella viruses isolated in China

    SciTech Connect

    Zhang, Y.; Burbank, D.E.; Van Etten, J.L. )

    1988-09-01

    Plaque-forming viruses of the unicellular, eukaryotic, exsymbiotic, Chlorella-like green algae strain NC64A, which are common in the United States, were also present in fresh water collected in the People's Republic of China. Seven of the Chinese viruses were examined in detail and compared with the Chlorella viruses previously isolated in the United States. Like the American viruses, the Chinese viruses were large polyhedra and sensitive to chloroform. They contained numerous structural proteins and large double-stranded DNA genomes of at least 300 kilobase pairs. Each of the DNAs from the Chinese viruses contained 5-methyldeoxycytosine, which varied from 12.6 to 46.7% of the deoxycytosine, and N{sup 6}-methyldeoxyadenosine, which varied from 2.2 to 28.3% of the deoxyadenosine. Four of the Chinese virus DNAs hybridized extensively with {sup 32}P-labeled DNA from the American virus PBCV-1, and three hybridized poorly.

  19. Special Issue: Honey Bee Viruses

    PubMed Central

    Gisder, Sebastian; Genersch, Elke

    2015-01-01

    Pollination of flowering plants is an important ecosystem service provided by wild insect pollinators and managed honey bees. Hence, losses and declines of pollinating insect species threaten human food security and are of major concern not only for apiculture or agriculture but for human society in general. Honey bee colony losses and bumblebee declines have attracted intensive research interest over the last decade and although the problem is far from being solved we now know that viruses are among the key players of many of these bee losses and bumblebee declines. With this special issue on bee viruses we, therefore, aimed to collect high quality original papers reflecting the current state of bee virus research. To this end, we focused on newly discovered viruses (Lake Sinai viruses, bee macula-like virus), or a so far neglected virus species (Apis mellifera filamentous virus), and cutting edge technologies (mass spectrometry, RNAi approach) applied in the field. PMID:26702462

  20. Testing for Human Immunodeficiency Virus

    MedlinePlus

    ... incisions made in the mother’s abdomen and uterus. Human Immunodeficiency Virus (HIV): A virus that attacks certain cells of the body’s immune system and causes acquired immunodeficiency syndrome (AIDS). Immune System: ...

  1. Emerging issues in virus taxonomy.

    PubMed

    van Regenmortel, Marc H V; Mahy, Brian W J

    2004-01-01

    Viruses occupy a unique position in biology. Although they possess some of the properties of living systems such as having a genome, they are actually nonliving infectious entities and should not be considered microorganisms. A clear distinction should be drawn between the terms virus, virion, and virus species. Species is the most fundamental taxonomic category used in all biological classification. In 1991, the International Committee on Taxonomy of Viruses (ICTV) decided that the category of virus species should be used in virus classification together with the categories of genus and family. More than 50 ICTV study groups were given the task of demarcating the 1,550 viral species that were recognized in the 7th ICTV report, which was published in 2000. We briefly describe the changes in virus classification that were introduced in that report. We also discuss recent proposals to introduce a nonlatinized binomial nomenclature for virus species. PMID:15078590

  2. Special Issue: Honey Bee Viruses.

    PubMed

    Gisder, Sebastian; Genersch, Elke

    2015-10-01

    Pollination of flowering plants is an important ecosystem service provided by wild insect pollinators and managed honey bees. Hence, losses and declines of pollinating insect species threaten human food security and are of major concern not only for apiculture or agriculture but for human society in general. Honey bee colony losses and bumblebee declines have attracted intensive research interest over the last decade and although the problem is far from being solved we now know that viruses are among the key players of many of these bee losses and bumblebee declines. With this special issue on bee viruses we, therefore, aimed to collect high quality original papers reflecting the current state of bee virus research. To this end, we focused on newly discovered viruses (Lake Sinai viruses, bee macula-like virus), or a so far neglected virus species (Apis mellifera filamentous virus), and cutting edge technologies (mass spectrometry, RNAi approach) applied in the field. PMID:26702462

  3. Ebola (Ebola Virus Disease): Prevention

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Ebola (Ebola Virus Disease) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Ebola (Ebola Virus Disease) About Ebola Questions & Answers 2014 ...

  4. Ebola (Ebola Virus Disease): Transmission

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Ebola (Ebola Virus Disease) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Ebola (Ebola Virus Disease) About Ebola Questions & Answers 2014 ...

  5. Ebola (Ebola Virus Disease): Treatment

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Ebola (Ebola Virus Disease) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Ebola (Ebola Virus Disease) About Ebola Questions & Answers 2014 ...

  6. Ebola (Ebola Virus Disease): Diagnosis

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Ebola (Ebola Virus Disease) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Ebola (Ebola Virus Disease) About Ebola Questions & Answers 2014 ...

  7. Production of virus resistant plants

    DOEpatents

    Dougherty, W.G.; Lindbo, J.A.

    1996-12-10

    A method of suppressing virus gene expression in plants using untranslatable plus sense RNA is disclosed. The method is useful for the production of plants that are resistant to virus infection. 9 figs.

  8. Zika Virus Infection and Microcephaly.

    PubMed

    Millichap, J Gordon

    2016-01-01

    A Task Force established by the Brazil Ministry of Health investigated the possible association of microcephaly with Zika virus infection during pregnancy and a registry for microcephaly cases among women suspected to have had Zika virus infection during pregnancy.

  9. Chlorella viruses isolated in China.

    PubMed Central

    Zhang, Y P; Burbank, D E; Van Etten, J L

    1988-01-01

    Plaque-forming viruses of the unicellular, eucaryotic, exsymbiotic, Chlorella-like green algae strain NC64A, which are common in the United States, were also present in fresh water collected in the People's Republic of China. Seven of the Chinese viruses were examined in detail and compared with the Chlorella viruses previously isolated in the United States. Like the American viruses, the Chinese viruses were large polyhedra and sensitive to chloroform. They contained numerous structural proteins and large double-stranded DNA genomes of at least 300 kilobase pairs. Each of the DNAs from the Chinese viruses contained 5-methyldeoxycytosine, which varied from 12.6 to 46.7% of the deoxycytosine, and N6-methyldeoxyadenosine, which varied from 2.2 to 28.3% of the deoxyadenosine. Four of the Chinese virus DNAs hybridized extensively with DNA from the American virus PBCV-1, and three hybridized poorly. Images PMID:2847652

  10. 9 CFR 113.215 - Bovine Virus Diarrhea Vaccine, Killed Virus.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Bovine Virus Diarrhea Vaccine, Killed... REQUIREMENTS Killed Virus Vaccines § 113.215 Bovine Virus Diarrhea Vaccine, Killed Virus. Bovine Virus Diarrhea Vaccine, Killed Virus, shall be prepared from virus-bearing cell culture fluids. Only Master Seed...

  11. 9 CFR 113.215 - Bovine Virus Diarrhea Vaccine, Killed Virus.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Bovine Virus Diarrhea Vaccine, Killed... REQUIREMENTS Killed Virus Vaccines § 113.215 Bovine Virus Diarrhea Vaccine, Killed Virus. Bovine Virus Diarrhea Vaccine, Killed Virus, shall be prepared from virus-bearing cell culture fluids. Only Master Seed...

  12. 9 CFR 113.215 - Bovine Virus Diarrhea Vaccine, Killed Virus.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Bovine Virus Diarrhea Vaccine, Killed... REQUIREMENTS Killed Virus Vaccines § 113.215 Bovine Virus Diarrhea Vaccine, Killed Virus. Bovine Virus Diarrhea Vaccine, Killed Virus, shall be prepared from virus-bearing cell culture fluids. Only Master Seed...

  13. 9 CFR 113.215 - Bovine Virus Diarrhea Vaccine, Killed Virus.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Bovine Virus Diarrhea Vaccine, Killed... REQUIREMENTS Killed Virus Vaccines § 113.215 Bovine Virus Diarrhea Vaccine, Killed Virus. Bovine Virus Diarrhea Vaccine, Killed Virus, shall be prepared from virus-bearing cell culture fluids. Only Master Seed...

  14. RNA-Seq reveals virus-virus and virus-plant interactions in nature.

    PubMed

    Kamitani, Mari; Nagano, Atsushi J; Honjo, Mie N; Kudoh, Hiroshi

    2016-11-01

    As research on plant viruses has focused mainly on crop diseases, little is known about these viruses in natural environments. To understand the ecology of viruses in natural systems, comprehensive information on virus-virus and virus-host interactions is required. We applied RNA-Seq to plants from a natural population of Arabidopsis halleri subsp. gemmifera to simultaneously determine the presence/absence of all sequence-reported viruses, identify novel viruses and quantify the host transcriptome. By introducing the criteria of read number and genome coverage, we detected infections by Turnip mosaic virus (TuMV), Cucumber mosaic virus and Brassica yellows virus Active TuMV replication was observed by ultramicroscopy. De novo assembly further identified a novel partitivirus, Arabidopsis halleri partitivirus 1 Interestingly, virus reads reached a maximum level that was equivalent to that of the host's total mRNA, although asymptomatic infection was common. AhgAGO2, a key gene in host defence systems, was upregulated in TuMV-infected plants. Multiple infection was frequent in TuMV-infected leaves, suggesting that TuMV facilitates multiple infection, probably by suppressing host RNA silencing. Revealing hidden plant-virus interactions in nature can enhance our understanding of biological interactions and may have agricultural applications. PMID:27549115

  15. Deformed wing virus.

    PubMed

    de Miranda, Joachim R; Genersch, Elke

    2010-01-01

    Deformed wing virus (DWV; Iflaviridae) is one of many viruses infecting honeybees and one of the most heavily investigated due to its close association with honeybee colony collapse induced by Varroadestructor. In the absence of V.destructor DWV infection does not result in visible symptoms or any apparent negative impact on host fitness. However, for reasons that are still not fully understood, the transmission of DWV by V.destructor to the developing pupae causes clinical symptoms, including pupal death and adult bees emerging with deformed wings, a bloated, shortened abdomen and discolouration. These bees are not viable and die soon after emergence. In this review we will summarize the historical and recent data on DWV and its relatives, covering the genetics, pathobiology, and transmission of this important viral honeybee pathogen, and discuss these within the wider theoretical concepts relating to the genetic variability and population structure of RNA viruses, the evolution of virulence and the development of disease symptoms.

  16. Oncolytic viruses: finally delivering

    PubMed Central

    Seymour, Leonard W; Fisher, Kerry D

    2016-01-01

    Oncolytic viruses can be found at the confluence of virology, genetic engineering and pharmacology where versatile platforms for molecularly targeted anticancer agents can be designed and optimised. Oncolytic viruses offer several important advantages over traditional approaches, including the following. (1) Amplification of the active agent (infectious virus particles) within the tumour. This avoids unnecessary exposure to normal tissues experienced during delivery of traditional stoichiometric chemotherapy and maximises the therapeutic index. (2) The active cell-killing mechanisms, often independent of programmed death mechanisms, should decrease the emergence of acquired drug resistance. (3) Lytic death of cancer cells provides a pro-inflammatory microenvironment and the potential for induction of an anticancer vaccine response. (4) Tumour-selective expression and secretion of encoded anticancer biologics, providing a new realm of potent and cost-effective-targeted therapeutics. PMID:26766734

  17. Viruses and Asthma

    PubMed Central

    Dulek, Daniel E.; Peebles, R. Stokes

    2011-01-01

    Background Viral respiratory infection has long been known to influence the occurrence of asthma exacerbations. Over the last twenty years much effort has been put into clarifying the role that viral respiratory infections play in the eventual development of asthma. Scope of Review In this review we give a general background of the role of viruses in the processes of asthma exacerbation and asthma induction. We review recent additions to the literature in the last three years with particular focus on clinical and epidemiologic investigations of influenza, rhinovirus, bocavirus, respiratory syncytial virus, and metapneumovirus. Major Conclusions The development of asthma emerges from a complex interaction of genetic predisposition and environmental factors with viral infection likely playing a significant role in the effect of environment on asthma inception. General Significance Further understanding of the role that viruses play in asthma exacerbation and inception will contribute to decreased asthma morbidity in the future. PMID:21291960

  18. Hendra virus and Nipah virus animal vaccines.

    PubMed

    Broder, Christopher C; Weir, Dawn L; Reid, Peter A

    2016-06-24

    Hendra virus (HeV) and Nipah virus (NiV) are zoonotic viruses that emerged in the mid to late 1990s causing disease outbreaks in livestock and people. HeV appeared in Queensland, Australia in 1994 causing a severe respiratory disease in horses along with a human case fatality. NiV emerged a few years later in Malaysia and Singapore in 1998-1999 causing a large outbreak of encephalitis with high mortality in people and also respiratory disease in pigs which served as amplifying hosts. The key pathological elements of HeV and NiV infection in several species of mammals, and also in people, are a severe systemic and often fatal neurologic and/or respiratory disease. In people, both HeV and NiV are also capable of causing relapsed encephalitis following recovery from an acute infection. The known reservoir hosts of HeV and NiV are several species of pteropid fruit bats. Spillovers of HeV into horses continue to occur in Australia and NiV has caused outbreaks in people in Bangladesh and India nearly annually since 2001, making HeV and NiV important transboundary biological threats. NiV in particular possesses several features that underscore its potential as a pandemic threat, including its ability to infect humans directly from natural reservoirs or indirectly from other susceptible animals, along with a capacity of limited human-to-human transmission. Several HeV and NiV animal challenge models have been developed which have facilitated an understanding of pathogenesis and allowed for the successful development of both active and passive immunization countermeasures.

  19. Hendra virus and Nipah virus animal vaccines.

    PubMed

    Broder, Christopher C; Weir, Dawn L; Reid, Peter A

    2016-06-24

    Hendra virus (HeV) and Nipah virus (NiV) are zoonotic viruses that emerged in the mid to late 1990s causing disease outbreaks in livestock and people. HeV appeared in Queensland, Australia in 1994 causing a severe respiratory disease in horses along with a human case fatality. NiV emerged a few years later in Malaysia and Singapore in 1998-1999 causing a large outbreak of encephalitis with high mortality in people and also respiratory disease in pigs which served as amplifying hosts. The key pathological elements of HeV and NiV infection in several species of mammals, and also in people, are a severe systemic and often fatal neurologic and/or respiratory disease. In people, both HeV and NiV are also capable of causing relapsed encephalitis following recovery from an acute infection. The known reservoir hosts of HeV and NiV are several species of pteropid fruit bats. Spillovers of HeV into horses continue to occur in Australia and NiV has caused outbreaks in people in Bangladesh and India nearly annually since 2001, making HeV and NiV important transboundary biological threats. NiV in particular possesses several features that underscore its potential as a pandemic threat, including its ability to infect humans directly from natural reservoirs or indirectly from other susceptible animals, along with a capacity of limited human-to-human transmission. Several HeV and NiV animal challenge models have been developed which have facilitated an understanding of pathogenesis and allowed for the successful development of both active and passive immunization countermeasures. PMID:27154393

  20. Protecting Your Computer from Viruses

    ERIC Educational Resources Information Center

    Descy, Don E.

    2006-01-01

    A computer virus is defined as a software program capable of reproducing itself and usually capable of causing great harm to files or other programs on the same computer. The existence of computer viruses--or the necessity of avoiding viruses--is part of using a computer. With the advent of the Internet, the door was opened wide for these…

  1. Avian influenza virus RNA extraction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The efficient extraction and purification of viral RNA is critical for down-stream molecular applications whether it is the sensitive and specific detection of virus in clinical samples, virus gene cloning and expression, or quantification of avian influenza (AI) virus by molecular methods from expe...

  2. Ipomoviruses: Squash vein yellowing virus, Cucumber vein yellowing virus, Cassava brown streak virus, and Ugandan cassava brown streak virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ipomoviruses including Squash vein yellowing virus, Cucumber vein yellowing virus and Cassava brown streak virus are currently causing significant economic impact on crop production in several regions of the world. Only recently have results of detailed characterization of their whitefly transmissi...

  3. Computer Bytes, Viruses and Vaccines.

    ERIC Educational Resources Information Center

    Palmore, Teddy B.

    1989-01-01

    Presents a history of computer viruses, explains various types of viruses and how they affect software or computer operating systems, and describes examples of specific viruses. Available vaccines are explained, and precautions for protecting programs and disks are given. (nine references) (LRW)

  4. An introduction to computer viruses

    SciTech Connect

    Brown, D.R.

    1992-03-01

    This report on computer viruses is based upon a thesis written for the Master of Science degree in Computer Science from the University of Tennessee in December 1989 by David R. Brown. This thesis is entitled An Analysis of Computer Virus Construction, Proliferation, and Control and is available through the University of Tennessee Library. This paper contains an overview of the computer virus arena that can help the reader to evaluate the threat that computer viruses pose. The extent of this threat can only be determined by evaluating many different factors. These factors include the relative ease with which a computer virus can be written, the motivation involved in writing a computer virus, the damage and overhead incurred by infected systems, and the legal implications of computer viruses, among others. Based upon the research, the development of a computer virus seems to require more persistence than technical expertise. This is a frightening proclamation to the computing community. The education of computer professionals to the dangers that viruses pose to the welfare of the computing industry as a whole is stressed as a means of inhibiting the current proliferation of computer virus programs. Recommendations are made to assist computer users in preventing infection by computer viruses. These recommendations support solid general computer security practices as a means of combating computer viruses.

  5. Ecology of prokaryotic viruses.

    PubMed

    Weinbauer, Markus G

    2004-05-01

    The finding that total viral abundance is higher than total prokaryotic abundance and that a significant fraction of the prokaryotic community is infected with phages in aquatic systems has stimulated research on the ecology of prokaryotic viruses and their role in ecosystems. This review treats the ecology of prokaryotic viruses ('phages') in marine, freshwater and soil systems from a 'virus point of view'. The abundance of viruses varies strongly in different environments and is related to bacterial abundance or activity suggesting that the majority of the viruses found in the environment are typically phages. Data on phage diversity are sparse but indicate that phages are extremely diverse in natural systems. Lytic phages are predators of prokaryotes, whereas lysogenic and chronic infections represent a parasitic interaction. Some forms of lysogeny might be described best as mutualism. The little existing ecological data on phage populations indicate a large variety of environmental niches and survival strategies. The host cell is the main resource for phages and the resource quality, i.e., the metabolic state of the host cell, is a critical factor in all steps of the phage life cycle. Virus-induced mortality of prokaryotes varies strongly on a temporal and spatial scale and shows that phages can be important predators of bacterioplankton. This mortality and the release of cell lysis products into the environment can strongly influence microbial food web processes and biogeochemical cycles. Phages can also affect host diversity, e.g., by 'killing the winner' and keeping in check competitively dominant species or populations. Moreover, they mediate gene transfer between prokaryotes, but this remains largely unknown in the environment. Genomics or proteomics are providing us now with powerful tools in phage ecology, but final testing will have to be performed in the environment. PMID:15109783

  6. Ecology of prokaryotic viruses.

    PubMed

    Weinbauer, Markus G

    2004-05-01

    The finding that total viral abundance is higher than total prokaryotic abundance and that a significant fraction of the prokaryotic community is infected with phages in aquatic systems has stimulated research on the ecology of prokaryotic viruses and their role in ecosystems. This review treats the ecology of prokaryotic viruses ('phages') in marine, freshwater and soil systems from a 'virus point of view'. The abundance of viruses varies strongly in different environments and is related to bacterial abundance or activity suggesting that the majority of the viruses found in the environment are typically phages. Data on phage diversity are sparse but indicate that phages are extremely diverse in natural systems. Lytic phages are predators of prokaryotes, whereas lysogenic and chronic infections represent a parasitic interaction. Some forms of lysogeny might be described best as mutualism. The little existing ecological data on phage populations indicate a large variety of environmental niches and survival strategies. The host cell is the main resource for phages and the resource quality, i.e., the metabolic state of the host cell, is a critical factor in all steps of the phage life cycle. Virus-induced mortality of prokaryotes varies strongly on a temporal and spatial scale and shows that phages can be important predators of bacterioplankton. This mortality and the release of cell lysis products into the environment can strongly influence microbial food web processes and biogeochemical cycles. Phages can also affect host diversity, e.g., by 'killing the winner' and keeping in check competitively dominant species or populations. Moreover, they mediate gene transfer between prokaryotes, but this remains largely unknown in the environment. Genomics or proteomics are providing us now with powerful tools in phage ecology, but final testing will have to be performed in the environment.

  7. Bagaza virus and Israel turkey meningoencephalomyelitis virus are a single virus species.

    PubMed

    Fernández-Pinero, Jovita; Davidson, Irit; Elizalde, Maia; Perk, Shimon; Khinich, Yevgeny; Jiménez-Clavero, Miguel Angel

    2014-04-01

    Bagaza virus (BAGV) and Israel turkey meningoencephalomyelitis virus (ITV) are classified in the genus Flavivirus of the family Flaviviridae. Serologically, they are closely related, belonging to the Ntaya serocomplex. Nucleotide sequences available to date consist of several complete sequences of BAGV isolates, but only partial sequences of ITV isolates. Sequence comparisons of partial envelope (E) and NS5 regions reveal a close genetic relationship between these viruses. Despite this, BAGV and ITV are considered as separate virus species in the database of the International Committee on Taxonomy of Viruses. In this work, complete nucleotide sequences for five ITV isolates are provided, thereby permitting a phylogenetic comparison with other complete sequences of flaviviruses in the Ntaya serogroup. We conclude that BAGV and ITV are the same virus species and propose that both viruses be designated by a new unified name: Avian meningoencephalomyelitis virus.

  8. [ZIKA--VIRUS INFECTION].

    PubMed

    Velev, V

    2016-01-01

    This review summarizes the knowledge of the scientific community for Zika-virus infection. It became popular because of severe congenital damage causes of CNS in newborns whose mothers are infected during pregnancy, as well as the risk of pandemic distribution. Discusses the peculiarities of the biology and ecology of vectors--blood-sucking mosquitoes Aedes; stages in the spread of infection and practical problems which caused during pregnancy. Attention is paid to the recommendations that allow leading national and international medical organizations to deal with the threat Zika-virus infection. PMID:27509655

  9. Zika virus: Indian perspectives.

    PubMed

    Mourya, Devendra T; Shil, Pratip; Sapkal, Gajanan N; Yadav, Pragya D

    2016-05-01

    The emergence of Zika virus (ZiV), a mosquito borne Flavivirus like dengue (DEN) and chikungunya (CHIK), in Brazil in 2014 and its spread to various countries have led to a global health emergency. Aedes aegypti is the major vector for ZiV. Fast dissemination of this virus in different geographical areas posses a major threat especially to regions where the population lacks herd immunity against the ZiV and there is abundance of Aedes mosquitoes. In this review, we focus on current global scenario, epidemiology, biology, diagnostic challenges and remedial measures for ZiVconsidering the Indian perspective.

  10. Zika Virus Outside Africa

    PubMed Central

    2009-01-01

    Zika virus (ZIKV) is a flavivirus related to yellow fever, dengue, West Nile, and Japanese encephalitis viruses. In 2007 ZIKV caused an outbreak of relatively mild disease characterized by rash, arthralgia, and conjunctivitis on Yap Island in the southwestern Pacific Ocean. This was the first time that ZIKV was detected outside of Africa and Asia. The history, transmission dynamics, virology, and clinical manifestations of ZIKV disease are discussed, along with the possibility for diagnostic confusion between ZIKV illness and dengue.The emergence of ZIKV outside of its previously known geographic range should prompt awareness of the potential for ZIKV to spread to other Pacific islands and the Americas. PMID:19788800

  11. Genome packaging in viruses.

    PubMed

    Sun, Siyang; Rao, Venigalla B; Rossmann, Michael G

    2010-02-01

    Genome packaging is a fundamental process in a viral life cycle. Many viruses assemble preformed capsids into which the genomic material is subsequently packaged. These viruses use a packaging motor protein that is driven by the hydrolysis of ATP to condense the nucleic acids into a confined space. How these motor proteins package viral genomes had been poorly understood until recently, when a few X-ray crystal structures and cryo-electron microscopy (cryo-EM) structures became available. Here we discuss various aspects of genome packaging and compare the mechanisms proposed for packaging motors on the basis of structural information. PMID:20060706

  12. [ZIKA--VIRUS INFECTION].

    PubMed

    Velev, V

    2016-01-01

    This review summarizes the knowledge of the scientific community for Zika-virus infection. It became popular because of severe congenital damage causes of CNS in newborns whose mothers are infected during pregnancy, as well as the risk of pandemic distribution. Discusses the peculiarities of the biology and ecology of vectors--blood-sucking mosquitoes Aedes; stages in the spread of infection and practical problems which caused during pregnancy. Attention is paid to the recommendations that allow leading national and international medical organizations to deal with the threat Zika-virus infection.

  13. Virus diseases of fish

    USGS Publications Warehouse

    Watson, Stanley W.

    1954-01-01

    The degenerative or non-neoplastic diseases of possible virus origin give the fish-culturist the most concern because of the severe mortalities resulting from infection. Epizootics of this nature have been reported in carp (Cyprinus carpio) and rainbow trout (Salmo gairdneri) in Europe, in acara (Geophagus brasiliensis) in South America, in kokanee, (Oncorhynchus nerka kennerlyi) and in sockeye salmon (Oncorhynchus nerka nerka) in the State of Washington. It has been demonstrated that each epizootic was caused by an infectious filterable agent, probably a virus.

  14. Schmallenberg virus infection.

    PubMed

    Wernike, K; Elbers, A; Beer, M

    2015-08-01

    Since Schmallenberg virus, an orthobunyavirus of the Simbu serogroup, was identified near the German-Dutch border for the first time in late 2011 it has spread extremely quickly and caused a large epidemic in European livestock. The virus, which is transmitted by Culicoides biting midges, infects domestic and wild ruminants. Adult animals show only mild clinical symptoms or none at all, whereas an infection during a critical period of gestation can lead to abortion, stillbirth or the birth of severely malformed offspring. The impact of the disease is usually greater in sheep than in cattle. Vaccination could be an important aspect of disease control. PMID:26601441

  15. Zika virus outside Africa.

    PubMed

    Hayes, Edward B

    2009-09-01

    Zika virus (ZIKV) is a flavivirus related to yellow fever, dengue, West Nile, and Japanese encephalitis viruses. In 2007 ZIKV caused an outbreak of relatively mild disease characterized by rash, arthralgia, and conjunctivitis on Yap Island in the southwestern Pacific Ocean. This was the first time that ZIKV was detected outside of Africa and Asia. The history, transmission dynamics, virology, and clinical manifestations of ZIKV disease are discussed, along with the possibility for diagnostic confusion between ZIKV illness and dengue.The emergence of ZIKV outside of its previously known geographic range should prompt awareness of the potential for ZIKV to spread to other Pacific islands and the Americas.

  16. Viruses and viral proteins

    PubMed Central

    Verdaguer, Nuria; Ferrero, Diego; Murthy, Mathur R. N.

    2014-01-01

    For more than 30 years X-ray crystallography has been by far the most powerful approach for determining the structures of viruses and viral proteins at atomic resolution. The information provided by these structures, which covers many important aspects of the viral life cycle such as cell-receptor recognition, viral entry, nucleic acid transfer and genome replication, has extensively enriched our vision of the virus world. Many of the structures available correspond to potential targets for antiviral drugs against important human pathogens. This article provides an overview of the current knowledge of different structural aspects of the above-mentioned processes. PMID:25485129

  17. Zika virus: Indian perspectives

    PubMed Central

    Mourya, Devendra T.; Shil, Pratip; Sapkal, Gajanan N.; Yadav, Pragya D.

    2016-01-01

    The emergence of Zika virus (ZiV), a mosquito borne Flavivirus like dengue (DEN) and chikungunya (CHIK), in Brazil in 2014 and its spread to various countries have led to a global health emergency. Aedes aegypti is the major vector for ZiV. Fast dissemination of this virus in different geographical areas posses a major threat especially to regions where the population lacks herd immunity against the ZiV and there is abundance of Aedes mosquitoes. In this review, we focus on current global scenario, epidemiology, biology, diagnostic challenges and remedial measures for ZiVconsidering the Indian perspective. PMID:27487998

  18. Human Immunodeficiency Virus Prevention.

    PubMed

    Davis, Teaniese Latham; DiClemente, Ralph

    2016-04-01

    Human immunodeficiency virus (HIV) is the virus that causes AIDS. Surveillance data from 2012 indicate an estimated 1.2 million people aged 13 years and older were living with HIV infection in the United States, and 12.8% do not know their status. There are approximately 50,000 new HIV infections annually. With no available cure for HIV, primary prevention to reduce incident cases of HIV is essential. Strategies to prevent HIV transmission include reducing sexual risk behavior and needle sharing. The Centers for Disease Control and Prevention has multiple resources available for primary and secondary prevention to reduce disease transmission and severity. PMID:26980130

  19. Zika virus: Indian perspectives.

    PubMed

    Mourya, Devendra T; Shil, Pratip; Sapkal, Gajanan N; Yadav, Pragya D

    2016-05-01

    The emergence of Zika virus (ZiV), a mosquito borne Flavivirus like dengue (DEN) and chikungunya (CHIK), in Brazil in 2014 and its spread to various countries have led to a global health emergency. Aedes aegypti is the major vector for ZiV. Fast dissemination of this virus in different geographical areas posses a major threat especially to regions where the population lacks herd immunity against the ZiV and there is abundance of Aedes mosquitoes. In this review, we focus on current global scenario, epidemiology, biology, diagnostic challenges and remedial measures for ZiVconsidering the Indian perspective. PMID:27487998

  20. Research on computer virus database management system

    NASA Astrophysics Data System (ADS)

    Qi, Guoquan

    2011-12-01

    The growing proliferation of computer viruses becomes the lethal threat and research focus of the security of network information. While new virus is emerging, the number of viruses is growing, virus classification increasing complex. Virus naming because of agencies' capture time differences can not be unified. Although each agency has its own virus database, the communication between each other lacks, or virus information is incomplete, or a small number of sample information. This paper introduces the current construction status of the virus database at home and abroad, analyzes how to standardize and complete description of virus characteristics, and then gives the information integrity, storage security and manageable computer virus database design scheme.

  1. [Epidemiology of infectious hematopoietic necrosis (IHN) of salmonid fish in France: study of the course of natural infection by combined use of viral and seroneutralization test and eradication attempts].

    PubMed

    Hattenberger-Baudouy, A M; Danton, M; Merle, G; de Kinkelin, P

    1995-01-01

    Infectious haematopoietic necrosis (IHN), a rhabdoviral infection of salmonid fish, was considered to be an exotic disease in Europe until it was recognized in France and Italy in 1987. In France, the existence of this new condition led the authorities in charge of animal health to order epidemiological studies to be undertaken. These studies were based upon virological, serological and experimental diagnostic methods and also encompassed disease eradication attempts. Studies were conducted at 7 fish farming sites, involved 1,545 salmonid fish, of which 848 were sacrificed, and represented 262 virological examinations and 1,782 serum neutralization tests. The presence of the IHN virus was detected in the 7 trout farm fish populations that were located in 5 regions, one of which was situated 600 km from the place where the first isolation of IHN virus was made. Moreover, 6 out of 7 rainbow trout populations reared in these farms also harboured viral haemorrhagic septicaemia virus (VHSV) often resulting in overt disease. Rainbow trout was the only salmonid fish species found infected with IHN. Overt infection, which was observed in fish ageing less than 2,200 degrees-days, always occurred at water temperatures below 14 degrees C, and the younger fish were more susceptible (mortality rate > or = 80%). Although the IHN virus is easily isolable from fish undergoing overt infection, it was hardly detectable in survivors until they were adults, at which stage the virus was shedded via sexual products which constituted suitable materials for virological examination and disease transmission assays. Survivors of overt and dormant IHN infection developed consistent immune response and special attention was paid to neutralizing antibodies (NAb) to IHN virus. The detection of such NAb in fish from infected farming sites or other NAb from presumably IHN-free sites, correlated fairly well with the presence and further detection of IHN virus among such fish populations. Our data

  2. Epidemiology of hemorrhagic fever viruses.

    PubMed

    LeDuc, J W

    1989-01-01

    Twelve distinct viruses associated with hemorrhagic fever in humans are classified among four families: Arenaviridae, which includes Lassa, Junin, and Machupo viruses; Bunyaviridae, which includes Rift Valley fever, Crimean-Congo hemorrhagic fever, and Hantaan viruses; Filoviridae, which includes Marburg and Ebola viruses; and Flaviviridae, which includes yellow fever, dengue, Kyasanur Forest disease, and Omsk viruses. Most hemorrhagic fever viruses are zoonoses, with the possible exception of the four dengue viruses, which may continually circulate among humans. Hemorrhagic fever viruses are found in both temperate and tropical habitats and generally infect both sexes and all ages, although the age and sex of those infected are frequently influenced by the possibility of occupational exposure. Transmission to humans is frequently by bite of an infected tick or mosquito or via aerosol from infected rodent hosts. Aerosol and nosocomial transmission are especially important with Lassa, Junin, Machupo, Crimean-Congo hemorrhagic fever, Marburg, and Ebola viruses. Seasonality of hemorrhagic fever among humans is influenced for the most part by the dynamics of infected arthropod or vertebrate hosts. Mammals, especially rodents, appear to be important natural hosts for many hemorrhagic fever viruses. The transmission cycle for each hemorrhagic fever virus is distinct and is dependent upon the characteristics of the primary vector species and the possibility for its contact with humans.

  3. Turnip Yellow Mosaic Virus

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The bumpy exterior of the turnip yellow mosaic virus (TYMV) protein coat, or capsid, was defined in detail by Dr. Alexander McPherson of the University of California, Irvin using proteins crystallized in space for analysis on Earth. TYMV is an icosahedral virus constructed from 180 copies of the same protein arranged into 12 clusters of five proteins (pentamers), and 20 clusters of six proteins (hexamers). The final TYMV structure led to the unexpected hypothesis that the virus releases its RNA by essentially chemical-mechanical means. Most viruses have fairly flat coats, but in TYNV, the fold in each protein, called the jellyroll, is clustered at the points where the protein pentamers and hexamers join. The jellyrolls are almost standing on end, producing a bumpy surface with knobs at all of the pentamers and hexamers. At the inside surface of the pentamers is a void that is not present at the hexamers. The coating had been seen in early stuties of TYMV, but McPherson's atomic structure shows much more detail. The inside surface is strikingly, and unexpectedly, different than the outside. While the pentamers contain a central void on the inside, the hexameric units contain peptides linked to each other, forming a ring or, more accurately, rings to fill the void. Credit: Dr. Alexander McPherson, University of California, Irvine

  4. From Shakespeare to Viruses

    ScienceCinema

    Sung-Hou Kim

    2010-01-08

    Berkeley Lab scientists have created a unique new tool for analyzing and comparing long sets of data, be it the genomes of mammals or viruses, or the works of Shakespeare. The results of the Shakespeare analysis surprised scholars with their accuracy

  5. Viruses of haloarchaea.

    PubMed

    Luk, Alison W S; Williams, Timothy J; Erdmann, Susanne; Papke, R Thane; Cavicchioli, Ricardo

    2014-01-01

    In hypersaline environments, haloarchaea (halophilic members of the Archaea) are the dominant organisms, and the viruses that infect them, haloarchaeoviruses are at least ten times more abundant. Since their discovery in 1974, described haloarchaeoviruses include head-tailed, pleomorphic, spherical and spindle-shaped morphologies, representing Myoviridae, Siphoviridae, Podoviridae, Pleolipoviridae, Sphaerolipoviridae and Fuselloviridae families. This review overviews current knowledge of haloarchaeoviruses, providing information about classification, morphotypes, macromolecules, life cycles, genetic manipulation and gene regulation, and host-virus responses. In so doing, the review incorporates knowledge from laboratory studies of isolated viruses, field-based studies of environmental samples, and both genomic and metagenomic analyses of haloarchaeoviruses. What emerges is that some haloarchaeoviruses possess unique morphological and life cycle properties, while others share features with other viruses (e.g., bacteriophages). Their interactions with hosts influence community structure and evolution of populations that exist in hypersaline environments as diverse as seawater evaporation ponds, to hot desert or Antarctic lakes. The discoveries of their wide-ranging and important roles in the ecology and evolution of hypersaline communities serves as a strong motivator for future investigations of both laboratory-model and environmental systems. PMID:25402735

  6. From Shakespeare to Viruses

    SciTech Connect

    Sung-Hou Kim

    2009-02-09

    Berkeley Lab scientists have created a unique new tool for analyzing and comparing long sets of data, be it the genomes of mammals or viruses, or the works of Shakespeare. The results of the Shakespeare analysis surprised scholars with their accuracy

  7. From Shakespeare to Viruses

    ScienceCinema

    Kim, Sung-Hou

    2013-05-29

    Berkeley Lab scientists have created a unique new tool for analyzing and comparing long sets of data, be it the genomes of mammals or viruses, or the works of Shakespeare. The results of the Shakespeare analysis surprised scholars with their accuracy.

  8. Human Viruses and Cancer

    PubMed Central

    Morales-Sánchez, Abigail; Fuentes-Pananá, Ezequiel M.

    2014-01-01

    The first human tumor virus was discovered in the middle of the last century by Anthony Epstein, Bert Achong and Yvonne Barr in African pediatric patients with Burkitt’s lymphoma. To date, seven viruses -EBV, KSHV, high-risk HPV, MCPV, HBV, HCV and HTLV1- have been consistently linked to different types of human cancer, and infections are estimated to account for up to 20% of all cancer cases worldwide. Viral oncogenic mechanisms generally include: generation of genomic instability, increase in the rate of cell proliferation, resistance to apoptosis, alterations in DNA repair mechanisms and cell polarity changes, which often coexist with evasion mechanisms of the antiviral immune response. Viral agents also indirectly contribute to the development of cancer mainly through immunosuppression or chronic inflammation, but also through chronic antigenic stimulation. There is also evidence that viruses can modulate the malignant properties of an established tumor. In the present work, causation criteria for viruses and cancer will be described, as well as the viral agents that comply with these criteria in human tumors, their epidemiological and biological characteristics, the molecular mechanisms by which they induce cellular transformation and their associated cancers. PMID:25341666

  9. From Shakespeare to Viruses

    SciTech Connect

    Kim, Sung-Hou

    2009-01-01

    Berkeley Lab scientists have created a unique new tool for analyzing and comparing long sets of data, be it the genomes of mammals or viruses, or the works of Shakespeare. The results of the Shakespeare analysis surprised scholars with their accuracy.

  10. Cold Facts about Viruses.

    ERIC Educational Resources Information Center

    Pea, Celeste; Sterling, Donna R.

    2002-01-01

    Provides ways for students to demonstrate their understanding of scientific concepts and skills. Describes a mini-unit around the cold in which students can relate humans to viruses. Includes activities and a modified simulation that provides questions to guide students. Discusses ways that allows students to apply prior knowledge, take ownership…

  11. Viruses of Haloarchaea

    PubMed Central

    Luk, Alison W. S.; Williams, Timothy J.; Erdmann, Susanne; Papke, R. Thane; Cavicchioli, Ricardo

    2014-01-01

    In hypersaline environments, haloarchaea (halophilic members of the Archaea) are the dominant organisms, and the viruses that infect them, haloarchaeoviruses are at least ten times more abundant. Since their discovery in 1974, described haloarchaeoviruses include head-tailed, pleomorphic, spherical and spindle-shaped morphologies, representing Myoviridae, Siphoviridae, Podoviridae, Pleolipoviridae, Sphaerolipoviridae and Fuselloviridae families. This review overviews current knowledge of haloarchaeoviruses, providing information about classification, morphotypes, macromolecules, life cycles, genetic manipulation and gene regulation, and host-virus responses. In so doing, the review incorporates knowledge from laboratory studies of isolated viruses, field-based studies of environmental samples, and both genomic and metagenomic analyses of haloarchaeoviruses. What emerges is that some haloarchaeoviruses possess unique morphological and life cycle properties, while others share features with other viruses (e.g., bacteriophages). Their interactions with hosts influence community structure and evolution of populations that exist in hypersaline environments as diverse as seawater evaporation ponds, to hot desert or Antarctic lakes. The discoveries of their wide-ranging and important roles in the ecology and evolution of hypersaline communities serves as a strong motivator for future investigations of both laboratory-model and environmental systems. PMID:25402735

  12. Satellite RNAs and Satellite Viruses.

    PubMed

    Palukaitis, Peter

    2016-03-01

    Satellite RNAs and satellite viruses are extraviral components that can affect either the pathogenicity, the accumulation, or both of their associated viruses while themselves being dependent on the associated viruses as helper viruses for their infection. Most of these satellite RNAs are noncoding RNAs, and in many cases, have been shown to alter the interaction of their helper viruses with their hosts. In only a few cases have the functions of these satellite RNAs in such interactions been studied in detail. In particular, work on the satellite RNAs of Cucumber mosaic virus and Turnip crinkle virus have provided novel insights into RNAs functioning as noncoding RNAs. These effects are described and potential roles for satellite RNAs in the processes involved in symptom intensification or attenuation are discussed. In most cases, models describing these roles involve some aspect of RNA silencing or its suppression, either directly or indirectly involving the particular satellite RNA.

  13. Bat flight and zoonotic viruses

    USGS Publications Warehouse

    O'Shea, Thomas; Cryan, Paul M.; Cunningham, Andrew A.; Fooks, Anthony R.; Hayman, David T.S.; Luis, Angela D.; Peel, Alison J.; Plowright, Raina K.; Wood, James L.N.

    2014-01-01

    Bats are sources of high viral diversity and high-profile zoonotic viruses worldwide. Although apparently not pathogenic in their reservoir hosts, some viruses from bats severely affect other mammals, including humans. Examples include severe acute respiratory syndrome coronaviruses, Ebola and Marburg viruses, and Nipah and Hendra viruses. Factors underlying high viral diversity in bats are the subject of speculation. We hypothesize that flight, a factor common to all bats but to no other mammals, provides an intensive selective force for coexistence with viral parasites through a daily cycle that elevates metabolism and body temperature analogous to the febrile response in other mammals. On an evolutionary scale, this host–virus interaction might have resulted in the large diversity of zoonotic viruses in bats, possibly through bat viruses adapting to be more tolerant of the fever response and less virulent to their natural hosts.

  14. Bat flight and zoonotic viruses.

    PubMed

    O'Shea, Thomas J; Cryan, Paul M; Cunningham, Andrew A; Fooks, Anthony R; Hayman, David T S; Luis, Angela D; Peel, Alison J; Plowright, Raina K; Wood, James L N

    2014-05-01

    Bats are sources of high viral diversity and high-profile zoonotic viruses worldwide. Although apparently not pathogenic in their reservoir hosts, some viruses from bats severely affect other mammals, including humans. Examples include severe acute respiratory syndrome coronaviruses, Ebola and Marburg viruses, and Nipah and Hendra viruses. Factors underlying high viral diversity in bats are the subject of speculation. We hypothesize that flight, a factor common to all bats but to no other mammals, provides an intensive selective force for coexistence with viral parasites through a daily cycle that elevates metabolism and body temperature analogous to the febrile response in other mammals. On an evolutionary scale, this host-virus interaction might have resulted in the large diversity of zoonotic viruses in bats, possibly through bat viruses adapting to be more tolerant of the fever response and less virulent to their natural hosts.

  15. A vaccinia virus renaissance

    PubMed Central

    Verardi, Paulo H.; Titong, Allison; Hagen, Caitlin J.

    2012-01-01

    In 1796, Edward Jenner introduced the concept of vaccination with cowpox virus, an Orthopoxvirus within the family Poxviridae that elicits cross protective immunity against related orthopoxviruses, including smallpox virus (variola virus). Over time, vaccinia virus (VACV) replaced cowpox virus as the smallpox vaccine, and vaccination efforts eventually led to the successful global eradication of smallpox in 1979. VACV has many characteristics that make it an excellent vaccine and that were crucial for the successful eradication of smallpox, including (1) its exceptional thermal stability (a very important but uncommon characteristic in live vaccines), (2) its ability to elicit strong humoral and cell-mediated immune responses, (3) the fact that it is easy to propagate, and (4) that it is not oncogenic, given that VACV replication occurs exclusively within the host cell cytoplasm and there is no evidence that the viral genome integrates into the host genome. Since the eradication of smallpox, VACV has experienced a renaissance of interest as a viral vector for the development of recombinant vaccines, immunotherapies, and oncolytic therapies, as well as the development of next-generation smallpox vaccines. This revival is mainly due to the successful use and extensive characterization of VACV as a vaccine during the smallpox eradication campaign, along with the ability to genetically manipulate its large dsDNA genome while retaining infectivity and immunogenicity, its wide mammalian host range, and its natural tropism for tumor cells that allows its use as an oncolytic vector. This review provides an overview of new uses of VACV that are currently being explored for the development of vaccines, immunotherapeutics, and oncolytic virotherapies. PMID:22777090

  16. Molecular epidemiology and evolution of fish Novirhabdoviruses

    USGS Publications Warehouse

    Kurath, Gael

    2014-01-01

    The genus Novirhabdoviridae contains several of the important rhabdoviruses that infect fish hosts. There are four established virus species: Infectious hematopoietic necrosis virus (IHNV), Viral hemorrhagic septicemia virus (VHSV), Hirame rhabdovirus(HIRRV), and Snakehead rhabdovirus (SHRV). Viruses of these species vary in host and geographic range, and they have all been studied at the molecular and genomic level. As globally significant pathogens of cultured fish, IHNV and VHSV have been particularly well studied in terms of molecular epidemiology and evolution. Phylogenic analyses of hundreds of field isolates have defined five major genogroups of IHNV and four major genotypes of VHSV worldwide. These phylogenies are informed by the known histories of IHNV and VHSV, each involving a series of viral emergence events that are sometimes associated with host switches, most often into cultured rainbow trout. In general, IHNV has relatively low genetic diversity and a narrow host range, and has been spread from its endemic source in North American to Europe and Asia due to aquaculture activities. In contrast, VHSV has broad host range and high genetic diversity, and the source of emergence events is virus in widespread marine fish reservoirs in the northern Atlantic and Pacific Oceans. Common mechanisms of emergence and host switch events include use of raw feed, proximity to wild fish reservoirs of virus, and geographic translocations of virus or naive fish hosts associated with aquaculture.

  17. Molecular epidemiology of respiratory viruses in virus-induced asthma

    PubMed Central

    Ishioka, Taisei; Noda, Masahiro; Kozawa, Kunihisa; Kimura, Hirokazu

    2013-01-01

    Acute respiratory illness (ARI) due to various viruses is not only the most common cause of upper respiratory infection in humans but is also a major cause of morbidity and mortality, leading to diseases such as bronchiolitis and pneumonia. Previous studies have shown that respiratory syncytial virus (RSV), human rhinovirus (HRV), human metapneumovirus (HMPV), human parainfluenza virus (HPIV), and human enterovirus infections may be associated with virus-induced asthma. For example, it has been suggested that HRV infection is detected in the acute exacerbation of asthma and infection is prolonged. Thus it is believed that the main etiological cause of asthma is ARI viruses. Furthermore, the number of asthma patients in most industrial countries has greatly increased, resulting in a morbidity rate of around 10-15% of the population. However, the relationships between viral infections, host immune response, and host factors in the pathophysiology of asthma remain unclear. To gain a better understanding of the epidemiology of virus-induced asthma, it is important to assess both the characteristics of the viruses and the host defense mechanisms. Molecular epidemiology enables us to understand the pathogenesis of microorganisms by identifying specific pathways, molecules, and genes that influence the risk of developing a disease. However, the epidemiology of various respiratory viruses associated with virus-induced asthma is not fully understood. Therefore, in this article, we review molecular epidemiological studies of RSV, HRV, HPIV, and HMPV infection associated with virus-induced asthma. PMID:24062735

  18. Neuroteratogenic Viruses and Lessons for Zika Virus Models.

    PubMed

    Kim, Kenneth; Shresta, Sujan

    2016-08-01

    The Centers for Disease Control and Prevention has confirmed that Zika virus (ZIKV) causes congenital microcephaly. ZIKV now joins five other neuroteratogenic (NT) viruses in humans and ZIKV research is in its infancy. In addition, there is only one other NT human arbovirus (Venezuelan equine encephalitis virus), which is also poorly understood. But further insight into ZIKV can be found by evaluating arboviruses in domestic animals, of which there are at least seven NT viruses, three of which have been well studied. Here we review two key anatomical structures involved in modeling transplacental NT virus transmission: the placenta and the fetal blood-brain barrier. We then survey major research findings regarding transmission of NT viruses for guidance in establishing a mouse model of Zika disease that is crucial for a better understanding of ZIKV transmission and pathogenesis. PMID:27387029

  19. Neuroteratogenic Viruses and Lessons for Zika Virus Models.

    PubMed

    Kim, Kenneth; Shresta, Sujan

    2016-08-01

    The Centers for Disease Control and Prevention has confirmed that Zika virus (ZIKV) causes congenital microcephaly. ZIKV now joins five other neuroteratogenic (NT) viruses in humans and ZIKV research is in its infancy. In addition, there is only one other NT human arbovirus (Venezuelan equine encephalitis virus), which is also poorly understood. But further insight into ZIKV can be found by evaluating arboviruses in domestic animals, of which there are at least seven NT viruses, three of which have been well studied. Here we review two key anatomical structures involved in modeling transplacental NT virus transmission: the placenta and the fetal blood-brain barrier. We then survey major research findings regarding transmission of NT viruses for guidance in establishing a mouse model of Zika disease that is crucial for a better understanding of ZIKV transmission and pathogenesis.

  20. Single Virus Genomics: A New Tool for Virus Discovery

    PubMed Central

    Allen, Lisa Zeigler; Ishoey, Thomas; Novotny, Mark A.; McLean, Jeffrey S.; Lasken, Roger S.; Williamson, Shannon J.

    2011-01-01

    Whole genome amplification and sequencing of single microbial cells has significantly influenced genomics and microbial ecology by facilitating direct recovery of reference genome data. However, viral genomics continues to suffer due to difficulties related to the isolation and characterization of uncultivated viruses. We report here on a new approach called ‘Single Virus Genomics’, which enabled the isolation and complete genome sequencing of the first single virus particle. A mixed assemblage comprised of two known viruses; E. coli bacteriophages lambda and T4, were sorted using flow cytometric methods and subsequently immobilized in an agarose matrix. Genome amplification was then achieved in situ via multiple displacement amplification (MDA). The complete lambda phage genome was recovered with an average depth of coverage of approximately 437X. The isolation and genome sequencing of uncultivated viruses using Single Virus Genomics approaches will enable researchers to address questions about viral diversity, evolution, adaptation and ecology that were previously unattainable. PMID:21436882

  1. Detection of sweet potato viruses in Yunnan and genetic diversity analysis of the common viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two hundred seventy-nine samples with virus-like symptoms collected from 16 regions in Yunnan Province were tested by RT-PCR/PCR using virus-specific primers for 8 sweet potato viruses. Six viruses, Sweet potato chlorotic fleck virus (SPCFV), Sweet Potato feathery mottle virus (SPFMV), Sweet potato ...

  2. Discrete virus infection model of hepatitis B virus.

    PubMed

    Zhang, Pengfei; Min, Lequan; Pian, Jianwei

    2015-01-01

    In 1996 Nowak and his colleagues proposed a differential equation virus infection model, which has been widely applied in the study for the dynamics of hepatitis B virus (HBV) infection. Biological dynamics may be described more practically by discrete events rather than continuous ones. Using discrete systems to describe biological dynamics should be reasonable. Based on one revised Nowak et al's virus infection model, this study introduces a discrete virus infection model (DVIM). Two equilibriums of this model, E1 and E2, represents infection free and infection persistent, respectively. Similar to the case of the basic virus infection model, this study deduces a basic virus reproductive number R0 independing on the number of total cells of an infected target organ. A proposed theorem proves that if the basic virus reproductive number R0<1 then the virus free equilibrium E1 is locally stable. The DVIM is more reasonable than an abstract discrete susceptible-infected-recovered model (SIRS) whose basic virus reproductive number R0 is relevant to the number of total cells of the infected target organ. As an application, this study models the clinic HBV DNA data of a patient who was accepted via anti-HBV infection therapy with drug lamivudine. The results show that the numerical simulation is good in agreement with the clinic data.

  3. Hetdex: Virus Instrument

    NASA Astrophysics Data System (ADS)

    Lee, Hanshin; Hill, G. J.; DePoy, D. L.; Tuttle, S.; Marshall, J. L.; Vattiat, B. L.; Prochaska, T.; Chonis, T. S.; Allen, R.; HETDEX Collaboration

    2012-01-01

    The Visible Integral-field-unit Replicable Unit Spectrograph (VIRUS) instrument is made up of 150+ individually compact and identical spectrographs, each fed by a fiber integral-field unit. The instrument provides integral field spectroscopy at wavelengths between 350nm and 550nm of over 33,600 spatial elements per observation, each 1.8 sq. arcsec on the sky, at R 700. The instrument will be fed by a new wide-field corrector (WFC) of the Hobby-Eberly Telescope (HET) with increased science field of view as large as 22arcmin diameter and telescope aperture of 10m. This will enable the HETDEX, a large area blind survey of Lyman-alpha emitting galaxies at redshift z < 3.5. The status of VIRUS instrument construction is summarized.

  4. Mechanisms of Virus Assembly

    PubMed Central

    Perlmutter, Jason D.; Hagan, Michael F.

    2015-01-01

    Viruses are nanoscale entities containing a nucleic acid genome encased in a protein shell called a capsid, and in some cases surrounded by a lipid bilayer membrane. This review summarizes the physics that govern the processes by which capsids assembles within their host cells and in vitro. We describe the thermodynamics and kinetics for assembly of protein subunits into icosahedral capsid shells, and how these are modified in cases where the capsid assembles around a nucleic acid or on a lipid bilayer. We present experimental and theoretical techniques that have been used to characterize capsid assembly, and we highlight aspects of virus assembly which are likely to receive significant attention in the near future. PMID:25532951

  5. The encephalomyocarditis virus

    PubMed Central

    Carocci, Margot; Bakkali-Kassimi, Labib

    2012-01-01

    The encephalomyocarditis virus (EMCV) is a small non-enveloped single-strand RNA virus, the causative agent of not only myocarditis and encephalitis, but also neurological diseases, reproductive disorders and diabetes in many mammalian species. EMCV pathogenesis appears to be viral strain- and host-specific, and a better understanding of EMCV virulence factors is increasingly required. Indeed, EMCV is often used as a model for diabetes and viral myocarditis, and is also widely used in immunology as a double-stranded RNA stimulus in the study of Toll-like as well as cytosolic receptors. However, EMCV virulence and properties have often been neglected. Moreover, EMCV is able to infect humans albeit with a low morbidity. Progress on xenografts, such as pig heart transplantation in humans, has raised safety concerns that need to be explored. In this review we will highlight the biology of EMCV and all known and potential virulence factors. PMID:22722247

  6. Cytomegalovirus: the stealth virus.

    PubMed

    Robinson, Sharon

    2016-05-01

    Cytomegalovirus (CMV) is an infection, part of the herpes family of viruses which, if contracted during pregnancy, cancause devastating effects on the newborn baby. This article is written by the trustee of a volunteer-based charity, mostly run by mothers of CMV children, who are striving to raise awareness of this infection, which is more common than Down's syndrome, listeria and toxoplasmosis, and is theprimary preventable cause of childhood hearing loss.

  7. VIRUS instrument collimator assembly

    NASA Astrophysics Data System (ADS)

    Marshall, Jennifer L.; DePoy, Darren L.; Prochaska, Travis; Allen, Richard D.; Williams, Patrick; Rheault, Jean-Philippe; Li, Ting; Nagasawa, Daniel Q.; Akers, Christopher; Baker, David; Boster, Emily; Campbell, Caitlin; Cook, Erika; Elder, Alison; Gary, Alex; Glover, Joseph; James, Michael; Martin, Emily; Meador, Will; Mondrik, Nicholas; Rodriguez-Patino, Marisela; Villanueva, Steven; Hill, Gary J.; Tuttle, Sarah; Vattiat, Brian; Lee, Hanshin; Chonis, Taylor S.; Dalton, Gavin B.; Tacon, Mike

    2014-07-01

    The Visual Integral-Field Replicable Unit Spectrograph (VIRUS) instrument is a baseline array 150 identical fiber fed optical spectrographs designed to support observations for the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX). The collimator subassemblies of the instrument have been assembled in a production line and are now complete. Here we review the design choices and assembly practices used to produce a suite of identical low-cost spectrographs in a timely fashion using primarily unskilled labor.

  8. Hepatitis C Virus.

    PubMed

    Kim, Arthur

    2016-09-01

    This issue provides a clinical overview of hepatitis C virus, focusing on transmission, prevention, screening, diagnosis, evaluation, and treatment. The content of In the Clinic is drawn from the clinical information and education resources of the American College of Physicians (ACP), including MKSAP (Medical Knowledge and Self-Assessment Program). Annals of Internal Medicine editors develop In the Clinic in collaboration with the ACP's Medical Education and Publishing divisions and with the assistance of additional science writers and physician writers. PMID:27595226

  9. Physical Studies on Pox Viruses

    PubMed Central

    McCrea, J. F.; Preiss, John W.; O'Loughlin, Jean

    1960-01-01

    Vaccinia virus was irradiated in vacuo with low-voltage electrons of restricted ranges. It was found that the pock-forming ability of the virus was not decreased after bombardment with electrons penetrating 100 A beneath the virus surface. There was very slight reduction in titer with large doses of electrons penetrating 330 A, but a sudden marked drop in infectivity occurred after exposure to electrons penetrating 500 to 700 A. Electrons of higher energies, including those capable of penetrating the virus particle completely, did not produce significant further fall in infectivity titer. It is concluded that a highly radiation-sensitive unit essential for pock formation is situated 500 to 700 A beneath the surface of the virus particle, possibly in the form of a shell. The relation of this finding to the known structure of the virus and to other radiation data on the dimensions of the infectious unit is discussed. PMID:13773839

  10. Proteorhodopsin genes in giant viruses.

    PubMed

    Yutin, Natalya; Koonin, Eugene V

    2012-01-01

    Viruses with large genomes encode numerous proteins that do not directly participate in virus biogenesis but rather modify key functional systems of infected cells. We report that a distinct group of giant viruses infecting unicellular eukaryotes that includes Organic Lake Phycodnaviruses and Phaeocystis globosa virus encode predicted proteorhodopsins that have not been previously detected in viruses. Search of metagenomic sequence data shows that putative viral proteorhodopsins are extremely abundant in marine environments. Phylogenetic analysis suggests that giant viruses acquired proteorhodopsins via horizontal gene transfer from proteorhodopsin-encoding protists although the actual donor(s) could not be presently identified. The pattern of conservation of the predicted functionally important amino acid residues suggests that viral proteorhodopsin homologs function as sensory rhodopsins. We hypothesize that viral rhodopsins modulate light-dependent signaling, in particular phototaxis, in infected protists.

  11. Principles of Virus Structural Organization

    PubMed Central

    Prasad, B.V. Venkataram; Schmid, Michael F

    2013-01-01

    Viruses, the molecular nanomachines infecting hosts ranging from prokaryotes to eukaryotes, come in different sizes, shapes and symmetries. Questions such as what principles govern their structural organization, what factors guide their assembly, how these viruses integrate multifarious functions into one unique structure have enamored researchers for years. In the last five decades, following Caspar and Klug's elegant conceptualization of how viruses are constructed, high resolution structural studies using X-ray crystallography and more recently cryo-EM techniques have provided a wealth of information on structures of variety of viruses. These studies have significantly furthered our understanding of the principles that underlie structural organization in viruses. Such an understanding has practical impact in providing a rational basis for the design and development of antiviral strategies. In this chapter, we review principles underlying capsid formation in a variety of viruses, emphasizing the recent developments along with some historical perspective. PMID:22297509

  12. Ebola Virus Disease

    PubMed Central

    Kourtis, Athena P.; Appelgren, Kristie; Chevalier, Michelle S.; McElroy, Anita

    2015-01-01

    Ebola virus is one of the most deadly pathogens known to infect humans. The current Ebola outbreak in West Africa is unprecedented in magnitude and duration and, as of November 30, 2014, shows no signs of abating. For the first time, cases of Ebola virus disease have been diagnosed in the US, originating from patients who traveled during the incubation period. The outbreak has generated worldwide concern. It is clear that U.S. physicians need to be aware of this disease, know when to consider Ebola and how to care for the patient as well as protect themselves. Children comprise a small percentage of all cases globally, likely because of their lower risk of exposure given social and cultural practices. Limited evidence is available on pediatric disease course and prognosis. In this article, we present an overview of the pathogen, its epidemiology and transmission, clinical and laboratory manifestations, treatment and infection control procedures, with an emphasis on what is known about Ebola virus disease in the pediatric population. PMID:25831417

  13. Detection of dengue virus.

    PubMed

    Tripathi, Nagesh K; Shrivastava, Ambuj; Dash, Paban K; Jana, Asha M

    2011-01-01

    Global incidence of dengue has increased considerably over the past decade. Dengue fever (DF) is a self-limiting disease; however, dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS) are fatal. Since there is no therapy and vaccine against dengue, timely diagnosis is therefore necessary for patient management. Laboratory diagnosis is carried out by virus isolation, demonstration of viral antigen, presence of viral nucleic acid, and antibodies. Further, recombinant dengue envelope protein can be used to detect specific antibodies, both IgG and IgM against all four serotypes of virus using an E. coli vector. The purified protein can then be used for detection of dengue specific IgG or IgM antibodies in patient serum with higher sensitivity and specificity, than that of traditional assays. Molecular detection can be accomplished by a one-step, single-tube, rapid, multiplex, RT-PCR for serotype determination. Despite many advantages of the modern techniques, isolation of virus is still considered as "gold-standard" in dengue diagnosis.

  14. Parainfluenza Virus Infection.

    PubMed

    Branche, Angela R; Falsey, Ann R

    2016-08-01

    Human parainfluenza viruses (HPIVs) are single-stranded, enveloped RNA viruses of the Paramyoviridaie family. There are four serotypes which cause respiratory illnesses in children and adults. HPIVs bind and replicate in the ciliated epithelial cells of the upper and lower respiratory tract and the extent of the infection correlates with the location involved. Seasonal HPIV epidemics result in a significant burden of disease in children and account for 40% of pediatric hospitalizations for lower respiratory tract illnesses (LRTIs) and 75% of croup cases. Parainfluenza viruses are associated with a wide spectrum of illnesses which include otitis media, pharyngitis, conjunctivitis, croup, tracheobronchitis, and pneumonia. Uncommon respiratory manifestations include apnea, bradycardia, parotitis, and respiratory distress syndrome and rarely disseminated infection. Immunity resulting from disease in childhood is incomplete and reinfection with HPIV accounts for 15% of respiratory illnesses in adults. Severe disease and fatal pneumonia may occur in elderly and immunocompromised adults. HPIV pneumonia in recipients of hematopoietic stem cell transplant (HSCT) is associated with 50% acute mortality and 75% mortality at 6 months. Though sensitive molecular diagnostics are available to rapidly diagnose HPIV infection, effective antiviral therapies are not available. Currently, treatment for HPIV infection is supportive with the exception of croup where the use of corticosteroids has been found to be beneficial. Several novel drugs including DAS181 appear promising in efforts to treat severe disease in immunocompromised patients, and vaccines to decrease the burden of disease in young children are in development. PMID:27486735

  15. Photoreactivation of a Cytoplasmic Virus

    PubMed Central

    Pfefferkorn, E. R.; Boyle, Mary K.

    1972-01-01

    Ultraviolet light-inactivated frog virus 3 is efficiently photoreactivated by chick embryo cells. A cellular enzyme is presumably responsible for this repair of viral deoxyribonucleic acid, for the phenomenon is insensitive to an inhibitor of protein synthesis and is not seen in mammalian cells that are known to lack photoreactivating enzyme. Since frog virus 3 is a cytoplasmic virus, functionally significant amounts of photoreactivating enzyme are probably present in the cytoplasm of chick embryo cells. PMID:5062749

  16. [Hemorrhagic fever viruses in Madagascar].

    PubMed

    Fontenille, D; Mathiot, C; Coulanges, P

    1988-01-01

    The authors remind, what are the viral haemorrhagic fevers, and explain the situation in Madagascar. The viruses of Crimée-Congo haemorrhagic fever, Rift valley fever and haemorrhagic fever with renal syndrome are present in Madagascar. There is no real proof about the presence of Dengue viruses. The yellow fever viruses have never been stown off. It seems that there was not diagnosed outbreak of haemorrhagic fever, since the beginning of our century.

  17. Viruses manipulate the marine environment.

    PubMed

    Rohwer, Forest; Thurber, Rebecca Vega

    2009-05-14

    Marine viruses affect Bacteria, Archaea and eukaryotic organisms and are major components of the marine food web. Most studies have focused on their role as predators and parasites, but many of the interactions between marine viruses and their hosts are much more complicated. A series of recent studies has shown that viruses have the ability to manipulate the life histories and evolution of their hosts in remarkable ways, challenging our understanding of this almost invisible world.

  18. Aetiology of Neonatal Septicaemia in Qatif, Saudi Arabia.

    ERIC Educational Resources Information Center

    Elbashier, Ali M.; And Others

    1994-01-01

    Of the 1,797 babies admitted to a hospital in Saudi Arabia over a 3-year period, 8% were documented as having NNS. Identified several gram-positive bacteria, several gram-negative bacteria, and candida albicans as etiological agents in the cases of NNS. Determined the antibiotic susceptibility of the bacteria. (BC)

  19. Bacterial septicaemia in prerecruit edible crabs, Cancer pagurus L.

    PubMed

    Smith, A L; Whitten, M M A; Hirschle, L; Pope, E C; Wootton, E C; Vogan, C L; Rowley, A F

    2014-08-01

    Juvenile edible crabs, Cancer pagurus L., were surveyed from Mumbles Head and Oxwich Bay in South Wales, UK, and the number of heterotrophic bacteria and vibrios in the hemolymph was determined. The percentage of crabs with hemolymph containing bacteria was variable over the survey with higher numbers of animals affected in summer than in winter. Post-moult crabs contained significantly higher numbers of heterotrophic bacteria in the hemolymph than pre- and intermoult animals. Crabs with cuticular damage to the gills also had significantly higher numbers of bacteria in the hemolymph. Crabs were found to have a high prevalence of infection by the dinoflagellate, Hematodinium. Such animals had significantly fewer bacteria in the blood in comparison with Hematodinium-free animals. Of the 463 crabs surveyed, only 3 individuals had hemolymph containing 2000 + CFU mL(-1). Based on 16S rRNA gene sequences, two of these crabs contained a Vibrio pectenicida-like isolate, while the other had a mixed assemblage of vibrios. Although 59% of the crabs surveyed had culturable bacteria in the hemolymph, the majority only had small numbers (<2000 CFU mL(-1) ), suggesting that such infections may be of limited importance to the sustainability of the crab fishery in this region.

  20. Introducing Virological Concepts Using an Insect Virus.

    ERIC Educational Resources Information Center

    Sheppard, Roger F.

    1980-01-01

    A technique is presented which utilizes wax moth larvae in a laboratory investigation of an insect virus. Describes how an insect virus can be used to introduce undergraduate biology students to laboratory work on viruses and several virological concepts. (SA)

  1. Selecting Viruses for the Seasonal Influenza Vaccine

    MedlinePlus

    ... which viruses are selected for use in vaccine production? The influenza viruses in the seasonal flu vaccine ... to get a good vaccine virus for vaccine production? There are a number of factors that can ...

  2. Variant (Swine Origin) Influenza Viruses in Humans

    MedlinePlus

    ... What's this? Submit Button Past Newsletters Variant Influenza Viruses: Background and CDC Risk Assessment and Reporting Language: ... Background CDC Assessment Reporting Background On Variant Influenza Viruses Swine flu viruses do not normally infect humans. ...

  3. Dengue Virus May Bolster Zika's Attack

    MedlinePlus

    ... dengue fever virus may increase the severity of Zika virus, a new study says. Early stage laboratory findings ... Services, or federal policy. More Health News on: Zika Virus Recent Health News Related MedlinePlus Health Topics Dengue ...

  4. Human Immunodeficiency Virus (HIV) Primary Infection

    MedlinePlus

    ... rashes clinical tools newsletter | contact Share | Human Immunodeficiency Virus (HIV) Primary Infection Information for adults A A ... weeks following exposure to HIV (the human immunodeficiency virus). Chronic infection with this virus can cause AIDS ( ...

  5. Emergence of influenza A viruses.

    PubMed Central

    Webby, R J; Webster, R G

    2001-01-01

    Pandemic influenza in humans is a zoonotic disease caused by the transfer of influenza A viruses or virus gene segments from animal reservoirs. Influenza A viruses have been isolated from avian and mammalian hosts, although the primary reservoirs are the aquatic bird populations of the world. In the aquatic birds, influenza is asymptomatic, and the viruses are in evolutionary stasis. The aquatic bird viruses do not replicate well in humans, and these viruses need to reassort or adapt in an intermediate host before they emerge in human populations. Pigs can serve as a host for avian and human viruses and are logical candidates for the role of intermediate host. The transmission of avian H5N1 and H9N2 viruses directly to humans during the late 1990s showed that land-based poultry also can serve between aquatic birds and humans as intermediate hosts of influenza viruses. That these transmission events took place in Hong Kong and China adds further support to the hypothesis that Asia is an epicentre for influenza and stresses the importance of surveillance of pigs and live-bird markets in this area. PMID:11779380

  6. Nuclear entry of DNA viruses

    PubMed Central

    Fay, Nikta; Panté, Nelly

    2015-01-01

    DNA viruses undertake their replication within the cell nucleus, and therefore they must first deliver their genome into the nucleus of their host cells. Thus, trafficking across the nuclear envelope is at the basis of DNA virus infections. Nuclear transport of molecules with diameters up to 39 nm is a tightly regulated process that occurs through the nuclear pore complex (NPC). Due to the enormous diversity of virus size and structure, each virus has developed its own strategy for entering the nucleus of their host cells, with no two strategies alike. For example, baculoviruses target their DNA-containing capsid to the NPC and subsequently enter the nucleus intact, while the hepatitis B virus capsid crosses the NPC but disassembles at the nuclear side of the NPC. For other viruses such as herpes simplex virus and adenovirus, although both dock at the NPC, they have each developed a distinct mechanism for the subsequent delivery of their genome into the nucleus. Remarkably, other DNA viruses, such as parvoviruses and human papillomaviruses, access the nucleus through an NPC-independent mechanism. This review discusses our current understanding of the mechanisms used by DNA viruses to deliver their genome into the nucleus, and further presents the experimental evidence for such mechanisms. PMID:26029198

  7. Review: influenza virus in pigs.

    PubMed

    Crisci, Elisa; Mussá, Tufária; Fraile, Lorenzo; Montoya, Maria

    2013-10-01

    Influenza virus disease still remains one of the major threats to human health, involving a wide range of animal species and pigs play an important role in influenza ecology. Pigs were labeled as "mixing vessels" since they are susceptible to infection with avian, human and swine influenza viruses and genetic reassortment between these viruses can occur. After the H1N1 influenza pandemic of 2009 with a swine origin virus, the most recent research in "influenzology" is directed at improving knowledge of porcine influenza virus infection. This tendency is probably due to the fact that domestic pigs are closely related to humans and represent an excellent animal model to study various microbial infectious diseases. In spite of the role of the pig in influenza virus ecology, swine immune responses against influenza viruses are not fully understood. Considering these premises, the aim of this review is to focus on the in vitro studies performed with porcine cells and influenza virus and on the immune responses of pigs against human, avian and swine influenza viruses in vivo. The increased acceptance of pigs as suitable and valuable models in the scientific community may stimulate the development of new tools to assess porcine immune responses, paving the way for their consideration as the future "gold standard" large-animal model in immunology.

  8. RECOVIR Software for Identifying Viruses

    NASA Technical Reports Server (NTRS)

    Chakravarty, Sugoto; Fox, George E.; Zhu, Dianhui

    2013-01-01

    Most single-stranded RNA (ssRNA) viruses mutate rapidly to generate a large number of strains with highly divergent capsid sequences. Determining the capsid residues or nucleotides that uniquely characterize these strains is critical in understanding the strain diversity of these viruses. RECOVIR (an acronym for "recognize viruses") software predicts the strains of some ssRNA viruses from their limited sequence data. Novel phylogenetic-tree-based databases of protein or nucleic acid residues that uniquely characterize these virus strains are created. Strains of input virus sequences (partial or complete) are predicted through residue-wise comparisons with the databases. RECOVIR uses unique characterizing residues to identify automatically strains of partial or complete capsid sequences of picorna and caliciviruses, two of the most highly diverse ssRNA virus families. Partition-wise comparisons of the database residues with the corresponding residues of more than 300 complete and partial sequences of these viruses resulted in correct strain identification for all of these sequences. This study shows the feasibility of creating databases of hitherto unknown residues uniquely characterizing the capsid sequences of two of the most highly divergent ssRNA virus families. These databases enable automated strain identification from partial or complete capsid sequences of these human and animal pathogens.

  9. Semliki Forest virus and Sindbis virus, but not vaccinia virus, require glycolysis for optimal replication.

    PubMed

    Findlay, James S; Ulaeto, David

    2015-09-01

    Viruses are obligate intracellular pathogens which rely on the cell's machinery to produce the energy and macromolecules required for replication. Infection is associated with a modified metabolic profile and one pathway which can be modified is glycolysis. In this study, we investigated if the glycolysis pathway is required for alphavirus replication. Pre-treatment of Vero cells with three different glycolysis inhibitors (2-deoxyglucose, lonidamine and oxamate) resulted in a significant reduction (but not abrogation) of Semliki Forest virus and Sindbis virus replication, but not of the unrelated virus, vaccinia virus. Reduced virus yield was not associated with any significant cytotoxic effect and delayed treatment up to 3 h post-infection still resulted in a significant reduction. This suggested that glycolysis is required for optimal replication of alphaviruses by supporting post-entry life cycle steps.

  10. Structure of Flexible Filamentous Plant Viruses

    SciTech Connect

    Kendall, Amy; McDonald, Michele; Bian, Wen; Bowles, Timothy; Baumgarten, Sarah C.; Shi, Jian; Stewart, Phoebe L.; Bullitt, Esther; Gore, David; Irving, Thomas C.; Havens, Wendy M.; Ghabrial, Said A.; Wall, Joseph S.; Stubbs, Gerald

    2008-10-23

    Flexible filamentous viruses make up a large fraction of the known plant viruses, but in comparison with those of other viruses, very little is known about their structures. We have used fiber diffraction, cryo-electron microscopy, and scanning transmission electron microscopy to determine the symmetry of a potyvirus, soybean mosaic virus; to confirm the symmetry of a potexvirus, potato virus X; and to determine the low-resolution structures of both viruses. We conclude that these viruses and, by implication, most or all flexible filamentous plant viruses share a common coat protein fold and helical symmetry, with slightly less than 9 subunits per helical turn.

  11. Computer virus information update CIAC-2301

    SciTech Connect

    Orvis, W.J.

    1994-01-15

    While CIAC periodically issues bulletins about specific computer viruses, these bulletins do not cover all the computer viruses that affect desktop computers. The purpose of this document is to identify most of the known viruses for the MS-DOS and Macintosh platforms and give an overview of the effects of each virus. The authors also include information on some windows, Atari, and Amiga viruses. This document is revised periodically as new virus information becomes available. This document replaces all earlier versions of the CIAC Computer virus Information Update. The date on the front cover indicates date on which the information in this document was extracted from CIAC`s Virus database.

  12. Zika virus: epidemiology, clinical features and host-virus interactions.

    PubMed

    Hamel, Rodolphe; Liégeois, Florian; Wichit, Sineewanlaya; Pompon, Julien; Diop, Fodé; Talignani, Loïc; Thomas, Frédéric; Desprès, Philippe; Yssel, Hans; Missé, Dorothée

    2016-01-01

    Very recently, Zika virus (ZIKV) has gained a medical importance following the large-scale epidemics in South Pacific and Latin America. This paper reviews information on the epidemiology and clinical features of Zika disease with a particular emphasis on the host-virus interactions that contribute to the pathogenicity of ZIKV in humans.

  13. Uukuniemi Virus as a Tick-Borne Virus Model

    PubMed Central

    Mazelier, Magalie; Rouxel, Ronan Nicolas; Zumstein, Michael; Mancini, Roberta; Bell-Sakyi, Lesley

    2016-01-01

    ABSTRACT In the last decade, novel tick-borne pathogenic phleboviruses in the family Bunyaviridae, all closely related to Uukuniemi virus (UUKV), have emerged on different continents. To reproduce the tick-mammal switch in vitro, we first established a reverse genetics system to rescue UUKV with a genome close to that of the authentic virus isolated from the Ixodes ricinus tick reservoir. The IRE/CTVM19 and IRE/CTVM20 cell lines, both derived from I. ricinus, were susceptible to the virus rescued from plasmid DNAs and supported production of the virus over many weeks, indicating that infection was persistent. The glycoprotein GC was mainly highly mannosylated on tick cell-derived viral progeny. The second envelope viral protein, GN, carried mostly N-glycans not recognized by the classical glycosidases peptide-N-glycosidase F (PNGase F) and endoglycosidase H (Endo H). Treatment with β-mercaptoethanol did not impact the apparent molecular weight of GN. On viruses originating from mammalian BHK-21 cells, GN glycosylations were exclusively sensitive to PNGase F, and the electrophoretic mobility of the protein was substantially slower after the reduction of disulfide bonds. Furthermore, the amount of viral nucleoprotein per focus forming unit differed markedly whether viruses were produced in tick or BHK-21 cells, suggesting a higher infectivity for tick cell-derived viruses. Together, our results indicate that UUKV particles derived from vector tick cells have glycosylation and structural specificities that may influence the initial infection in mammalian hosts. This study also highlights the importance of working with viruses originating from arthropod vector cells in investigations of the cell biology of arbovirus transmission and entry into mammalian hosts. IMPORTANCE Tick-borne phleboviruses represent a growing threat to humans globally. Although ticks are important vectors of infectious emerging diseases, previous studies have mainly involved virus stocks

  14. Virioplankton: Viruses in Aquatic Ecosystems†

    PubMed Central

    Wommack, K. Eric; Colwell, Rita R.

    2000-01-01

    The discovery that viruses may be the most abundant organisms in natural waters, surpassing the number of bacteria by an order of magnitude, has inspired a resurgence of interest in viruses in the aquatic environment. Surprisingly little was known of the interaction of viruses and their hosts in nature. In the decade since the reports of extraordinarily large virus populations were published, enumeration of viruses in aquatic environments has demonstrated that the virioplankton are dynamic components of the plankton, changing dramatically in number with geographical location and season. The evidence to date suggests that virioplankton communities are composed principally of bacteriophages and, to a lesser extent, eukaryotic algal viruses. The influence of viral infection and lysis on bacterial and phytoplankton host communities was measurable after new methods were developed and prior knowledge of bacteriophage biology was incorporated into concepts of parasite and host community interactions. The new methods have yielded data showing that viral infection can have a significant impact on bacteria and unicellular algae populations and supporting the hypothesis that viruses play a significant role in microbial food webs. Besides predation limiting bacteria and phytoplankton populations, the specific nature of virus-host interaction raises the intriguing possibility that viral infection influences the structure and diversity of aquatic microbial communities. Novel applications of molecular genetic techniques have provided good evidence that viral infection can significantly influence the composition and diversity of aquatic microbial communities. PMID:10704475

  15. Emerging tomato viruses in Florida

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tomato spotted wilt virus (TSWV) causes crop losses worldwide. This tospovirus is well-known for disease epidemics in vegetable, ornamental and peanut crops in the southeastern U.S. Two other tospoviruses have recently emerged in south Florida. Groundnut ringspot virus (GRSV) was first detected in ...

  16. Tobacco ringspot virus in Rubus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tobacco ringspot virus (TRSV) has a broad host range among woody and perennial plants and has been reported from blackberry but not from red or black raspberry. The virus has been detected in blackberry in the southeastern United States with a single report from blackberry in British Columbia, Cana...

  17. TOTAL CULTURABLE VIRUS QUANTAL ASSAY

    EPA Science Inventory

    This chapter describes a quantal method for assaying culturable human enteric viruses from water matrices. The assay differs from the plaque assay described in Chapter 10 (December 1987 Revision) in that it is based upon the direct microscopic viewing of cells for virus-induced ...

  18. Defining life: the virus viewpoint.

    PubMed

    Forterre, Patrick

    2010-04-01

    Are viruses alive? Until very recently, answering this question was often negative and viruses were not considered in discussions on the origin and definition of life. This situation is rapidly changing, following several discoveries that have modified our vision of viruses. It has been recognized that viruses have played (and still play) a major innovative role in the evolution of cellular organisms. New definitions of viruses have been proposed and their position in the universal tree of life is actively discussed. Viruses are no more confused with their virions, but can be viewed as complex living entities that transform the infected cell into a novel organism-the virus-producing virions. I suggest here to define life (an historical process) as the mode of existence of ribosome encoding organisms (cells) and capsid encoding organisms (viruses) and their ancestors. I propose to define an organism as an ensemble of integrated organs (molecular or cellular) producing individuals evolving through natural selection. The origin of life on our planet would correspond to the establishment of the first organism corresponding to this definition.

  19. Ebola Virus-Related Encephalitis.

    PubMed

    de Greslan, Thierry; Billhot, Magali; Rousseau, Claire; Mac Nab, Christine; Karkowski, Ludovic; Cournac, Jean-Marie; Bordes, Julien; Gagnon, Nicolas; Dubrous, Philippe; Duron, Sandrine; Moroge, Sophie; Quentin, Benoit; Koulibaly, Fassou; Bompaire, Flavie; Renard, Jean-Luc; Cellarier, Gilles

    2016-10-15

    Ebola patients frequently exhibit behavioral modifications with ideation slowing and aggressiveness, sometimes contrasting with mild severity of Ebola disease. We performed lumbar punctures in 3 patients with this presentation and found Ebola virus in all cerebrospinal fluid samples. This discovery helps to discuss the concept of a specific Ebola virus encephalitis. PMID:27418576

  20. Swine Influenza Virus: Emerging Understandings

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: In March-April 2009, a novel pandemic H1N1 emerged in the human population in North America [1]. The gene constellation of the emerging virus was demonstrated to be a combination of genes from swine influenza A viruses (SIV) of North American and Eurasian lineages that had never before...

  1. Paper Models Illustrating Virus Symmetry.

    ERIC Educational Resources Information Center

    McCarthy, D. A.

    1990-01-01

    Instructions are given for constructing two models, one to illustrate the general principles of symmetry in T=1, T=3, and T=4 viruses, and the other to illustrate the disposition of protein subunits in the T=3 plant viruses and the picornaviruses. (Author/CW)

  2. Oncolytic virus therapy for cancer.

    PubMed

    Goldufsky, Joe; Sivendran, Shanthi; Harcharik, Sara; Pan, Michael; Bernardo, Sebastian; Stern, Richard H; Friedlander, Philip; Ruby, Carl E; Saenger, Yvonne; Kaufman, Howard L

    2013-01-01

    The use of oncolytic viruses to treat cancer is based on the selection of tropic tumor viruses or the generation of replication selective vectors that can either directly kill infected tumor cells or increase their susceptibility to cell death and apoptosis through additional exposure to radiation or chemotherapy. In addition, viral vectors can be modified to promote more potent tumor cell death, improve the toxicity profile, and/or generate host antitumor immunity. A variety of viruses have been developed as oncolytic therapeutics, including adenovirus, vaccinia virus, herpesvirus, coxsackie A virus, Newcastle disease virus, and reovirus. The clinical development of oncolytic viral therapy has accelerated in the last few years, with several vectors entering clinical trials for a variety of cancers. In this review, current strategies to optimize the therapeutic effectiveness and safety of the major oncolytic viruses are discussed, and a summary of current clinical trials is provided. Further investigation is needed to characterize better the clinical impact of oncolytic viruses, but there are increasing data demonstrating the potential promise of this approach for the treatment of human and animal cancers.

  3. Oncolytic virus therapy for cancer

    PubMed Central

    Goldufsky, Joe; Sivendran, Shanthi; Harcharik, Sara; Pan, Michael; Bernardo, Sebastian; Stern, Richard H; Friedlander, Philip; Ruby, Carl E; Saenger, Yvonne; Kaufman, Howard L

    2013-01-01

    The use of oncolytic viruses to treat cancer is based on the selection of tropic tumor viruses or the generation of replication selective vectors that can either directly kill infected tumor cells or increase their susceptibility to cell death and apoptosis through additional exposure to radiation or chemotherapy. In addition, viral vectors can be modified to promote more potent tumor cell death, improve the toxicity profile, and/or generate host antitumor immunity. A variety of viruses have been developed as oncolytic therapeutics, including adenovirus, vaccinia virus, herpesvirus, coxsackie A virus, Newcastle disease virus, and reovirus. The clinical development of oncolytic viral therapy has accelerated in the last few years, with several vectors entering clinical trials for a variety of cancers. In this review, current strategies to optimize the therapeutic effectiveness and safety of the major oncolytic viruses are discussed, and a summary of current clinical trials is provided. Further investigation is needed to characterize better the clinical impact of oncolytic viruses, but there are increasing data demonstrating the potential promise of this approach for the treatment of human and animal cancers. PMID:27512656

  4. Group 2 vaccinia virus, Brazil.

    PubMed

    Assis, Felipe Lopes; Borges, Iara Apolinario; Ferreira, Paulo César Peregrino; Bonjardim, Cláudio Antônio; Trindade, Giliane de Souza; Lobato, Zélia Inês Portela; Guedes, Maria Isabel Maldonado; Mesquita, Vaz; Kroon, Erna Geessien; Abrahão, Jônatas Santos

    2012-12-01

    In 2011, vaccinia virus caused an outbreak of bovine vaccinia, affecting dairy cattle and dairy workers in Brazil. Genetic and phenotypic analyses identified this isolate as distinct from others recently identified, thereby reinforcing the hypothesis that different vaccinia virus strains co-circulate in Brazil.

  5. West Nile virus vaccine.

    PubMed

    Monath, T P; Arroyo, J; Miller, C; Guirakhoo, F

    2001-05-01

    Within the past 5 years, West Nile encephalitis has emerged as an important disease of humans and horses in Europe. In 1999, the disease appeared for the first time in the northeastern United States. West Nile virus (a mosquito-borne flavivirus) has flourished in the North American ecosystem and is expected to expand its geographic range. In this review, the rationale for a human and veterinary vaccine is presented and a novel approach for rapid development of a molecularly-defined, live, attenuated vaccine is described. The technology (ChimeriVax) is applicable to the development of vaccines against all flaviviruses, and products against Japanese encephalitis (a close relative of West Nile) and dengue are in or are nearing clinical trials, respectively. ChimeriVax vaccines utilize the safe and effective vaccine against the prototype flavivirus -yellow fever 17D- as a live vector. Infectious clone technology is used to replace the genes encoding the pre-membrane (prM) and envelope (E) protein of yellow fever 17D vaccine with the corresponding genes of the target virus (e.g., West Nile). The resulting chimeric virus contains the antigens responsible for protection against West Nile but retains the replication efficiency of yellow fever 17D. The ChimeriVax technology is well-suited to the rapid development of a West Nile vaccine, and clinical trials could begin as early as mid-2002. Other approaches to vaccine development are briefly reviewed. The aim of this brief review is to describe the features of West Nile encephalitis, a newly introduced infectious disease affecting humans, horses and wildlife in the United States; the rationale for rapid development of vaccines; and approaches to the development of vaccines against the disease.

  6. New aspects of influenza viruses.

    PubMed Central

    Shaw, M W; Arden, N H; Maassab, H F

    1992-01-01

    Influenza virus infections continue to cause substantial morbidity and mortality with a worldwide social and economic impact. The past five years have seen dramatic advances in our understanding of viral replication, evolution, and antigenic variation. Genetic analyses have clarified relationships between human and animal influenza virus strains, demonstrating the potential for the appearance of new pandemic reassortants as hemagglutinin and neuraminidase genes are exchanged in an intermediate host. Clinical trials of candidate live attenuated influenza virus vaccines have shown the cold-adapted reassortants to be a promising alternative to the currently available inactivated virus preparations. Modern molecular techniques have allowed serious consideration of new approaches to the development of antiviral agents and vaccines as the functions of the viral genes and proteins are further elucidated. The development of techniques whereby the genes of influenza viruses can be specifically altered to investigate those functions will undoubtedly accelerate the pace at which our knowledge expands. PMID:1310439

  7. Nonlytic spread of naked viruses.

    PubMed

    Bird, Sara W; Kirkegaard, Karla

    2015-01-01

    How do viruses spread from cell to cell? Enveloped viruses acquire their surrounding membranes by budding: either through the plasma membrane or an internal membrane of infected cells. Thus, a newly budded enveloped virus finds itself either in the extracellular milieu or in a lumenal compartment from which it can exit the cell by conventional secretion. On the other hand, naked viruses such as poliovirus, nodavirus, adenovirus, and SV40 lack an external membrane. They are simply protein-nucleic acid complexes within the cytoplasm or nucleus of the infected cell, and thus would seem to have no other exit route than cell lysis. We have presented the first documentation of nonlytic spread of a naked virus, and showed the interconnections between this event and the process or components of the autophagy pathway. PMID:25680079

  8. Nonlytic spread of naked viruses

    PubMed Central

    Bird, Sara W; Kirkegaard, Karla

    2015-01-01

    How do viruses spread from cell to cell? Enveloped viruses acquire their surrounding membranes by budding: either through the plasma membrane or an internal membrane of infected cells. Thus, a newly budded enveloped virus finds itself either in the extracellular milieu or in a lumenal compartment from which it can exit the cell by conventional secretion. On the other hand, naked viruses such as poliovirus, nodavirus, adenovirus, and SV40 lack an external membrane. They are simply protein-nucleic acid complexes within the cytoplasm or nucleus of the infected cell, and thus would seem to have no other exit route than cell lysis. We have presented the first documentation of nonlytic spread of a naked virus, and showed the interconnections between this event and the process or components of the autophagy pathway. PMID:25680079

  9. Movement of Viruses between Biomes

    PubMed Central

    Sano, Emiko; Carlson, Suzanne; Wegley, Linda; Rohwer, Forest

    2004-01-01

    Viruses are abundant in all known ecosystems. In the present study, we tested the possibility that viruses from one biome can successfully propagate in another. Viral concentrates were prepared from different near-shore marine sites, lake water, marine sediments, and soil. The concentrates were added to microcosms containing dissolved organic matter as a food source (after filtration to allow 100-kDa particles to pass through) and a 3% (vol/vol) microbial inoculum from a marine water sample (after filtration through a 0.45-μm-pore-size filter). Virus-like particle abundances were then monitored using direct counting. Viral populations from lake water, marine sediments, and soil were able to replicate when they were incubated with the marine microbes, showing that viruses can move between different ecosystems and propagate. These results imply that viruses can laterally transfer DNA between microbes in different biomes. PMID:15466522

  10. The ecology of Ebola virus.

    PubMed

    Groseth, Allison; Feldmann, Heinz; Strong, James E

    2007-09-01

    Since Ebola virus was first identified more than 30 years ago, tremendous progress has been made in understanding the molecular biology and pathogenesis of this virus. However, the means by which Ebola virus is maintained and transmitted in nature remains unclear despite dedicated efforts to answer these questions. Recent work has provided new evidence that fruit bats might have a role as a reservoir species, but it is not clear whether other species are also involved or how transmission to humans or apes takes place. Two opposing hypotheses for Ebola emergence have surfaced; one of long-term local persistence in a cryptic and infrequently contacted reservoir, versus another of a more recent introduction of the virus and directional spread through susceptible populations. Nevertheless, with the increasing frequency of human filovirus outbreaks and the tremendous impact of infection on the already threatened great ape populations, there is an urgent need to better understand the ecology of Ebola virus in nature. PMID:17698361

  11. Biosensing with Virus Electrode Hybrids

    PubMed Central

    Mohan, Kritika; Penner, Reginald M.; Weiss, Gregory A.

    2015-01-01

    Virus electrodes address two major challenges associated with biosensing. First, the surface of the viruses can be readily tailored for specific, high affinity binding to targeted biomarkers. Second, the viruses are entrapped in a conducting polymer for electrical resistance-based, quantitative measurement of biomarker concentration. To further enhance device sensitivity, two different ligands can be attached to the virus surface, and increase the apparent affinity for the biomarker. In the example presented here, the two ligands bind to the analyte in a bidentate binding mode with chelate-based avidity effect, and result in an 100 pM experimentally observed limit of detection for the cancer biomarker prostate-specific membrane antigen. The approach does not require enzymatic amplification, and allows reagent-free, real-time measurements. This article presents general protocols for the development of such biosensors with modified viruses for the enhanced detection of arbitrary target proteins. PMID:26344233

  12. [Classification of viruses by computer].

    PubMed

    Ageeva, O N; Andzhaparidze, O G; Kibardin, V M; Nazarova, G M; Pleteneva, E A

    1982-01-01

    The study used the information mass containing information on 83 viruses characterized by 41 markers. The suitability of one of the variants of cluster analysis for virus classification was demonstrated. It was established that certain stages of automatic allotment of viruses into groups by the degree of similarity of their properties end the formation of groups which consist of viruses sufficiently close to each other by their properties and are sufficiently isolated. Comparison of these groups with the classification proposed by the ICVT established their correspondence to individual families. Analysis of the obtained classification system permits sufficiently grounded conclusions to be drawn with regard to the classification position of certain viruses, the classification of which has not yet been completed by the ICVT.

  13. Marine Viruses: Truth or Dare

    NASA Astrophysics Data System (ADS)

    Breitbart, Mya

    2012-01-01

    Over the past two decades, marine virology has progressed from a curiosity to an intensely studied topic of critical importance to oceanography. At concentrations of approximately 10 million viruses per milliliter of surface seawater, viruses are the most abundant biological entities in the oceans. The majority of these viruses are phages (viruses that infect bacteria). Through lysing their bacterial hosts, marine phages control bacterial abundance, affect community composition, and impact global biogeochemical cycles. In addition, phages influence their hosts through selection for resistance, horizontal gene transfer, and manipulation of bacterial metabolism. Recent work has also demonstrated that marine phages are extremely diverse and can carry a variety of auxiliary metabolic genes encoding critical ecological functions. This review is structured as a scientific "truth or dare," revealing several well-established "truths" about marine viruses and presenting a few "dares" for the research community to undertake in future studies.

  14. Virus assembly, allostery, and antivirals

    PubMed Central

    Zlotnick, Adam; Mukhopadhyay, Suchetana

    2010-01-01

    Assembly of virus capsids and surface proteins must be regulated to ensure that the resulting complex is an infectious virion. Here we examine assembly of virus capsids, focusing on hepatitis B virus and bacteriophage MS2, and formation of glycoproteins in the alphaviruses. These systems are structurally and biochemically well-characterized and are simplest-case paradigms of self-assembly. Published data suggest that capsid and glycoprotein assembly is subject to allosteric regulation, that is, regulation at the level of conformational change. The hypothesis that allostery is a common theme in viruses suggests that deregulation of capsid and glycoprotein assembly by small molecule effectors will be an attractive antiviral strategy, as has been demonstrated with hepatitis B virus. PMID:21163649

  15. Two Virus-Induced MicroRNAs Known Only from Teleost Fishes Are Orthologues of MicroRNAs Involved in Cell Cycle Control in Humans

    PubMed Central

    Schyth, Brian Dall; Bela-ong, Dennis Berbulla; Jalali, Seyed Amir Hossein; Kristensen, Lasse Bøgelund Juel; Einer-Jensen, Katja; Pedersen, Finn Skou; Lorenzen, Niels

    2015-01-01

    MicroRNAs (miRNAs) are ~22 base pair-long non-coding RNAs which regulate gene expression in the cytoplasm of eukaryotic cells by binding to specific target regions in mRNAs to mediate transcriptional blocking or mRNA cleavage. Through their fundamental roles in cellular pathways, gene regulation mediated by miRNAs has been shown to be involved in almost all biological phenomena, including development, metabolism, cell cycle, tumor formation, and host-pathogen interactions. To address the latter in a primitive vertebrate host, we here used an array platform to analyze the miRNA response in rainbow trout (Oncorhynchus mykiss) following inoculation with the virulent fish rhabdovirus Viral hemorrhagic septicaemia virus. Two clustered miRNAs, miR-462 and miR-731 (herein referred to as miR-462 cluster), described only in teleost fishes, were found to be strongly upregulated, indicating their involvement in fish-virus interactions. We searched for homologues of the two teleost miRNAs in other vertebrate species and investigated whether findings related to ours have been reported for these homologues. Gene synteny analysis along with gene sequence conservation suggested that the teleost fish miR-462 and miR-731 had evolved from the ancestral miR-191 and miR-425 (herein called miR-191 cluster), respectively. Whereas the miR-462 cluster locus is found between two protein-coding genes (intergenic) in teleost fish genomes, the miR-191 cluster locus is found within an intron of a protein-coding gene (intragenic) in the human genome. Interferon (IFN)-inducible and immune-related promoter elements found upstream of the teleost miR-462 cluster locus suggested roles in immune responses to viral pathogens in fish, while in humans, the miR-191 cluster functionally associated with cell cycle regulation. Stimulation of fish cell cultures with the IFN inducer poly I:C accordingly upregulated the expression of miR-462 and miR-731, while no stimulatory effect on miR-191 and miR-425

  16. The Acute bee paralysis virus-Kashmir bee virus-Israeli acute paralysis virus complex.

    PubMed

    de Miranda, Joachim R; Cordoni, Guido; Budge, Giles

    2010-01-01

    Acute bee paralysis virus (ABPV), Kashmir bee virus (KBV) and Israeli acute paralysis virus (IAPV) are part of a complex of closely related viruses from the Family Dicistroviridae. These viruses have a widespread prevalence in honey bee (Apis mellifera) colonies and a predominantly sub-clinical etiology that contrasts sharply with the extremely virulent pathology encountered at elevated titres, either artificially induced or encountered naturally. These viruses are frequently implicated in honey bee colony losses, especially when the colonies are infested with the parasitic mite Varroa destructor. Here we review the historical and recent literature of this virus complex, covering history and origins; the geographic, host and tissue distribution; pathology and transmission; genetics and variation; diagnostics, and discuss these within the context of the molecular and biological similarities and differences between the viruses. We also briefly discuss three recent developments relating specifically to IAPV, concerning its association with Colony Collapse Disorder, treatment of IAPV infection with siRNA and possible honey bee resistance to IAPV.

  17. Hepatitis E Virus Infection

    PubMed Central

    Dalton, Harry R.; Abravanel, Florence; Izopet, Jacques

    2014-01-01

    SUMMARY Hepatitis E virus (HEV) infection is a worldwide disease. An improved understanding of the natural history of HEV infection has been achieved within the last decade. Several reservoirs and transmission modes have been identified. Hepatitis E is an underdiagnosed disease, in part due to the use of serological assays with low sensitivity. However, diagnostic tools, including nucleic acid-based tests, have been improved. The epidemiology and clinical features of hepatitis E differ between developing and developed countries. HEV infection is usually an acute self-limiting disease, but in developed countries it causes chronic infection with rapidly progressive cirrhosis in organ transplant recipients, patients with hematological malignancy requiring chemotherapy, and individuals with HIV. HEV also causes extrahepatic manifestations, including a number of neurological syndromes and renal injury. Acute infection usually requires no treatment, but chronic infection should be treated by reducing immunosuppression in transplant patients and/or the use of antiviral therapy. In this comprehensive review, we summarize the current knowledge about the virus itself, as well as the epidemiology, diagnostics, natural history, and management of HEV infection in developing and developed countries. PMID:24396139

  18. Chikungunya virus infection.

    PubMed

    Sam, I-C; AbuBakar, S

    2006-06-01

    Chikungunya virus (CHIKV) is a mosquito-borne alphavirus which causes epidemic fever, rash and polyarthralgia in Africa and Asia. Two outbreaks have been reported in Malaysia, in Klang, Selangor (1998) and Bagan Panchor, Perak (2006). It is not known if the outbreaks were caused by the recent introduction of CHIKV, or if the virus was already circulating in Malaysia. Seroprevalence studies from the 1960s suggested previous disease activity in certain parts of the country. In Asia, CHIKV is thought to be transmitted by the same mosquitoes as dengue, Aedes aegypti and Ae. albopictus. Due to similarities in clinical presentation with dengue, limited awareness, and a lack of laboratory diagnostic capability, CHIKV is probably often underdiagnosed or misdiagnosed as dengue. Treatment is supportive. The prognosis is generally good, although some patients experience chronic arthritis. With no vaccine or antiviral available, prevention and control depends on surveillance, early identification of outbreaks, and vector control. CHIKV should be borne in mind in sporadic cases, and in patients epidemiologically linked to ongoing local or international outbreaks or endemic areas.

  19. Dengue virus vaccine development.

    PubMed

    Yauch, Lauren E; Shresta, Sujan

    2014-01-01

    Dengue virus (DENV) is a significant cause of morbidity and mortality in tropical and subtropical regions, causing hundreds of millions of infections each year. Infections range from asymptomatic to a self-limited febrile illness, dengue fever (DF), to the life-threatening dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS). The expanding of the habitat of DENV-transmitting mosquitoes has resulted in dramatic increases in the number of cases over the past 50 years, and recent outbreaks have occurred in the United States. Developing a dengue vaccine is a global health priority. DENV vaccine development is challenging due to the existence of four serotypes of the virus (DENV1-4), which a vaccine must protect against. Additionally, the adaptive immune response to DENV may be both protective and pathogenic upon subsequent infection, and the precise features of protective versus pathogenic immune responses to DENV are unknown, complicating vaccine development. Numerous vaccine candidates, including live attenuated, inactivated, recombinant subunit, DNA, and viral vectored vaccines, are in various stages of clinical development, from preclinical to phase 3. This review will discuss the adaptive immune response to DENV, dengue vaccine challenges, animal models used to test dengue vaccine candidates, and historical and current dengue vaccine approaches.

  20. Hepatitis E virus infection.

    PubMed

    Kamar, Nassim; Dalton, Harry R; Abravanel, Florence; Izopet, Jacques

    2014-01-01

    Hepatitis E virus (HEV) infection is a worldwide disease. An improved understanding of the natural history of HEV infection has been achieved within the last decade. Several reservoirs and transmission modes have been identified. Hepatitis E is an underdiagnosed disease, in part due to the use of serological assays with low sensitivity. However, diagnostic tools, including nucleic acid-based tests, have been improved. The epidemiology and clinical features of hepatitis E differ between developing and developed countries. HEV infection is usually an acute self-limiting disease, but in developed countries it causes chronic infection with rapidly progressive cirrhosis in organ transplant recipients, patients with hematological malignancy requiring chemotherapy, and individuals with HIV. HEV also causes extrahepatic manifestations, including a number of neurological syndromes and renal injury. Acute infection usually requires no treatment, but chronic infection should be treated by reducing immunosuppression in transplant patients and/or the use of antiviral therapy. In this comprehensive review, we summarize the current knowledge about the virus itself, as well as the epidemiology, diagnostics, natural history, and management of HEV infection in developing and developed countries. PMID:24396139

  1. Comparison of Immunohistochemistry and Virus Isolation for Diagnosis of West Nile Virus

    PubMed Central

    Ellis, Angela E.; Mead, Daniel G.; Allison, Andrew B.; Gibbs, Samantha E. J.; Gottdenker, Nicole L.; Stallknecht, David E.; Howerth, Elizabeth W.

    2005-01-01

    Immunohistochemistry and virus isolation were performed on 1,057 birds. Immunohistochemistry, virus isolation, or both found 325 birds to be West Nile virus positive. Of these, 271 were positive by both methods. These results indicate that virus isolation and immunohistochemistry are approximately equal in their ability to detect West Nile virus. PMID:15956415

  2. Genome Sequence of Bivens Arm Virus, a Tibrovirus Belonging to the Species Tibrogargan virus (Mononegavirales: Rhabdoviridae)

    PubMed Central

    Hensley, Lisa E.

    2015-01-01

    The new rhabdoviral genus Tibrovirus currently has two members, Coastal Plains virus and Tibrogargan virus. Here, we report the coding-complete genome sequence of a putative member of this genus, Bivens Arm virus. A genomic comparison reveals Bivens Arm virus to be closely related to, but distinct from, Tibrogargan virus. PMID:25792044

  3. A single vertebrate DNA virus protein disarms invertebrate immunity to RNA virus infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Virus-host interactions drive a remarkable diversity of immune responses and countermeasures. While investigating virus-invertebrate host interactions we found that two RNA viruses with broad host ranges, vesicular stomatitis virus (VSV) and Sindbis virus (SINV), were unable to infect certain Lepido...

  4. Infectious vaccinia virus recombinants that express hepatitis B virus surface antigen

    NASA Astrophysics Data System (ADS)

    Smith, Geoffrey L.; Mackett, Michael; Moss, Bernard

    1983-04-01

    Potential live vaccines against hepatitis B virus have been produced. The coding sequence for hepatitis B virus surface antigen (HBsAg) has been inserted into the vaccinia virus genome under control of vaccinia virus early promoters. Cells infected with these vaccinia virus recombinants synthesize and excrete HBsAg and vaccinated rabbits rapidly produce antibodies to HBsAg.

  5. Influenza: a virus of our times

    PubMed Central

    McCaughey, Conall

    2010-01-01

    Viruses are successful and omnipresent. Influenza A is a particularly important virus of humans. The article reviews the 2009 emergence of the pandemic influenza A virus, focusing on the potential origin of the virus and the distinctive clinical and epidemiological impact of the 2009 pandemic. PMID:21116418

  6. Safe Computing: An Overview of Viruses.

    ERIC Educational Resources Information Center

    Wodarz, Nan

    2001-01-01

    A computer virus is a program that replicates itself, in conjunction with an additional program that can harm a computer system. Common viruses include boot-sector, macro, companion, overwriting, and multipartite. Viruses can be fast, slow, stealthy, and polymorphic. Anti-virus products are described. (MLH)

  7. The IFITMs Inhibit Zika Virus Replication.

    PubMed

    Savidis, George; Perreira, Jill M; Portmann, Jocelyn M; Meraner, Paul; Guo, Zhiru; Green, Sharone; Brass, Abraham L

    2016-06-14

    Zika virus has emerged as a severe health threat with a rapidly expanding range. The IFITM family of restriction factors inhibits the replication of a broad range of viruses, including the closely related flaviruses West Nile virus and dengue virus. Here, we show that IFITM1 and IFITM3 inhibit Zika virus infection early in the viral life cycle. Moreover, IFITM3 can prevent Zika-virus-induced cell death. These results suggest that strategies to boost the actions and/or levels of the IFITMs might be useful for inhibiting a broad range of emerging viruses.

  8. Defining Life: The Virus Viewpoint

    NASA Astrophysics Data System (ADS)

    Forterre, Patrick

    2010-04-01

    Are viruses alive? Until very recently, answering this question was often negative and viruses were not considered in discussions on the origin and definition of life. This situation is rapidly changing, following several discoveries that have modified our vision of viruses. It has been recognized that viruses have played (and still play) a major innovative role in the evolution of cellular organisms. New definitions of viruses have been proposed and their position in the universal tree of life is actively discussed. Viruses are no more confused with their virions, but can be viewed as complex living entities that transform the infected cell into a novel organism—the virus—producing virions. I suggest here to define life (an historical process) as the mode of existence of ribosome encoding organisms (cells) and capsid encoding organisms (viruses) and their ancestors. I propose to define an organism as an ensemble of integrated organs (molecular or cellular) producing individuals evolving through natural selection. The origin of life on our planet would correspond to the establishment of the first organism corresponding to this definition.

  9. Viruses and interactomes in translation.

    PubMed

    Meyniel-Schicklin, Laurène; de Chassey, Benoît; André, Patrice; Lotteau, Vincent

    2012-07-01

    A decade of high-throughput screenings for intraviral and virus-host protein-protein interactions led to the accumulation of data and to the development of theories on laws governing interactome organization for many viruses. We present here a computational analysis of intraviral protein networks (EBV, FLUAV, HCV, HSV-1, KSHV, SARS-CoV, VACV, and VZV) and virus-host protein networks (DENV, EBV, FLUAV, HCV, and VACV) from up-to-date interaction data, using various mathematical approaches. If intraviral networks seem to behave similarly, they are clearly different from the human interactome. Viral proteins target highly central human proteins, which are precisely the Achilles' heel of the human interactome. The intrinsic structural disorder is a distinctive feature of viral hubs in virus-host interactomes. Overlaps between virus-host data sets identify a core of human proteins involved in the cellular response to viral infection and in the viral capacity to hijack the cell machinery for viral replication. Host proteins that are strongly targeted by a virus seem to be particularly attractive for other viruses. Such protein-protein interaction networks and their analysis represent a powerful resource from a therapeutic perspective.

  10. Virus infection and knee injury.

    PubMed Central

    Driscoll, P; Venner, R; Clements, G B

    1987-01-01

    Serological evidence of virus infection was sought in 31 consecutive patients presenting with knee swelling and compared with age/sex-matched controls. In a normal age/sex-matched control group, 42% of patients had evidence of recent or past infection with Coxsackie B virus, emphasising the care required in the evaluation of the significance of Coxsackie B neutralization titres in individual patients. Of 12 patients presenting with knee swelling and a history of a twisting injury, eight had serological evidence of recent or past infection with Coxsackie B virus, and one had evidence of a current adenovirus infection. PMID:2825728

  11. Marburg Virus Reverse Genetics Systems

    PubMed Central

    Schmidt, Kristina Maria; Mühlberger, Elke

    2016-01-01

    The highly pathogenic Marburg virus (MARV) is a member of the Filoviridae family and belongs to the group of nonsegmented negative-strand RNA viruses. Reverse genetics systems established for MARV have been used to study various aspects of the viral replication cycle, analyze host responses, image viral infection, and screen for antivirals. This article provides an overview of the currently established MARV reverse genetic systems based on minigenomes, infectious virus-like particles and full-length clones, and the research that has been conducted using these systems. PMID:27338448

  12. Xenotropic Murine Leukemia Virus-related Virus (XMRV) Backgrounder

    Cancer.gov

    Researchers have not found evidence that XMRV causes any diseases in humans or in animals. The presence of an infectious agent, such as a virus, in diseased tissue does not mean that the agent causes the disease.

  13. Capillary electrophoresis of viruses, subviral particles and virus complexes.

    PubMed

    Kremser, Leopold; Bilek, Gerhard; Blaas, Dieter; Kenndler, Ernst

    2007-07-01

    CZE and CIEF were so far applied to the analysis of tobacco mosaic virus, Semliki forest virus, human rhinovirus, adenovirus, norovirus and the bacteriophages T5 and MS2. The concentration of viral or subviral particles, of capsid proteins and viral genomes were determined, their electrophoretic mobilities and pI values were measured and bioaffinity reactions between viruses and antibodies, antibody fragments and receptor fragments were assessed. The role of detergents added to the BGE to obtain reproducible electrophoretic conditions was elucidated. The analytes were detected via their UV-absorbance or via fluorescence after derivatization of the viral capsid, the nucleic acid, or both. A new dimension to the detection is added by the possibility of making use of the viral infectivity. At least in theory, this allows for the unequivocal identification of a single infectious virus particle after collection at the capillary outlet. This review summarizes the 25 papers so far published on this topic.

  14. Virus isolation for diagnosing dengue virus infections in returning travelers.

    PubMed

    Teichmann, D; Göbels, K; Niedrig, M; Sim-Brandenburg, J-W; Làge-Stehr, J; Grobusch, M P

    2003-11-01

    Dengue fever is recognized as one of the most frequent imported acute febrile illnesses affecting European tourists returning from the tropics. In order to assess the value of virus isolation for the diagnosis of dengue fever, 70 cases of dengue fever confirmed in German travelers during the period 1993-2001 were analyzed retrospectively. In 26 patients who had developed acute febrile illness within 2 weeks following their return from a trip to a dengue-endemic area, 9 of 13 attempts to isolate the virus were successful in sera drawn 1-5 days and 2 of 13 sera drawn 6-10 days after the onset of illness. DEN-1 was the most frequent serotype isolated. If performed early, virus isolation is a reliable tool for detecting dengue virus in returning travelers.

  15. Antiviral Drugs for Viruses Other Than Human Immunodeficiency Virus

    PubMed Central

    Razonable, Raymund R.

    2011-01-01

    Most viral diseases, with the exception of those caused by human immunodeficiency virus, are self-limited illnesses that do not require specific antiviral therapy. The currently available antiviral drugs target 3 main groups of viruses: herpes, hepatitis, and influenza viruses. With the exception of the antisense molecule fomivirsen, all antiherpes drugs inhibit viral replication by serving as competitive substrates for viral DNA polymerase. Drugs for the treatment of influenza inhibit the ion channel M2 protein or the enzyme neuraminidase. Combination therapy with Interferon-α and ribavirin remains the backbone treatment for chronic hepatitis C; the addition of serine protease inhibitors improves the treatment outcome of patients infected with hepatitis C virus genotype 1. Chronic hepatitis B can be treated with interferon or a combination of nucleos(t)ide analogues. Notably, almost all the nucleos(t) ide analogues for the treatment of chronic hepatitis B possess anti–human immunodeficiency virus properties, and they inhibit replication of hepatitis B virus by serving as competitive substrates for its DNA polymerase. Some antiviral drugs possess multiple potential clinical applications, such as ribavirin for the treatment of chronic hepatitis C and respiratory syncytial virus and cidofovir for the treatment of cytomegalovirus and other DNA viruses. Drug resistance is an emerging threat to the clinical utility of antiviral drugs. The major mechanisms for drug resistance are mutations in the viral DNA polymerase gene or in genes that encode for the viral kinases required for the activation of certain drugs such as acyclovir and ganciclovir. Widespread antiviral resistance has limited the clinical utility of M2 inhibitors for the prevention and treatment of influenza infections. This article provides an overview of clinically available antiviral drugs for the primary care physician, with a special focus on pharmacology, clinical uses, and adverse effects. PMID

  16. Cucumber mosaic virus, a model for RNA virus evolution.

    PubMed

    Roossinck, M J

    2001-03-01

    Summary Taxonomic relationships: Cucumber mosaic virus (CMV) is the type member of the Cucumovirus genus, in the family Bromoviridae. Additional members of the genus are Peanut stunt virus (PSV) and Tomato aspermy virus (TAV). The RNAs 3 of all members of the genus can be exchanged and still yield a viable virus, while the RNAs 1 and 2 can only be exchanged within a species. Physical properties: The virus particles are about 29 nm in diameter, and are composed of 180 subunits (T = 3 icosahedral symmetry). The particles sediment with an s value of approximately 98. The virions contain 18% RNA, and are highly labile, relying on RNA-protein interactions for their integrity. The three genomic RNAs, designated RNA 1 (3.3 kb in length), RNA 2 (3.0 kb) and RNA 3 (2.2 kb) are packaged in individual particles; a subgenomic RNA, RNA 4 (1.0 kb), is packaged with the genomic RNA 3, making all the particles roughly equivalent in composition. In some strains an additional subgenomic RNA, RNA 4A is also encapsidated at low levels. The genomic RNAs are single stranded, plus sense RNAs with 5' cap structures, and 3' conserved regions that can be folded into tRNA-like structures. Satellite RNAs: CMV can harbour molecular parasites known as satellite RNAs (satRNAs) that can dramatically alter the symptom phenotype induced by the virus. The CMV satRNAs do not encode any proteins but rely on the RNA for their biological activity. Hosts: CMV infects over 1000 species of hosts, including members of 85 plant families, making it the broadest host range virus known. The virus is transmitted from host to host by aphid vectors, in a nonpersistent manner. Useful web sites: http://mmtsb.scripps.edu/viper/1f15.html (structure); http://www.ncbi.nlm.nih.gov/ICTVdb/ICTVdB/10040001.htm (general information).

  17. Characterization of Sepik and Entebbe bat viruses closely related to yellow fever virus.

    PubMed

    Kuno, Goro; Chang, Gwong-Jen J

    2006-12-01

    Yellow fever virus has a special place in medical history as the first animal virus isolated and as the prototype virus in the genus Flavivirus, which contains many serious human pathogens. Only recently, its closely related viruses within the group were identified phylogenetically. In this study, we obtained complete or near complete genome sequences of two viruses most closely related to yellow fever virus: Sepik virus of Papua New Guinea and Entebbe bat virus of Africa. Based on full-genomic characterization and genomic traits among related viruses, we identified Sepik virus to be most closely related to yellow fever virus and analyzed the pattern of repeat and conserved sequence motifs in the 3'-noncoding region among the members of yellow fever virus cluster. We also discuss the geographic dispersal as a part of ecological traits of this lineage of flaviviruses.

  18. Zika virus infections.

    PubMed

    de Laval, F; Leparc-Goffart, I; Meynard, J-B; Daubigny, H; Simon, F; Briolant, S

    2016-05-01

    Since its discovery in 1947 in Uganda, the Zika virus (ZIKV) remained in the shadows emerging in 2007 in Micronesia, where hundreds of dengue-like syndromes were reported. Then, in 2013-2014, it was rife in French Polynesia, where the first neurological effects were observed. More recently, its arrival in Brazil was accompanied by an unusually high number of children with microcephaly born to mothers infected with ZIKV during the first trimester of pregnancy. In 2016, the World Health Organization declared ZIKV infection to be a public health emergency and now talks about a ZIKV pandemic. This review aims to summarize the current knowledge about ZIKV infection, successively addressing its transmission, epidemiology, clinical aspects, diagnosis, treatment, and prevention before discussing some perspectives. PMID:27412976

  19. West Nile virus meningoencephalitis

    PubMed Central

    DeBiasi, Roberta L.; Tyler, Kenneth L.

    2013-01-01

    SUMMARY Since its first appearance in the US in 1999, West Nile virus (WNV) has emerged as the most common cause of epidemic meningoencephalitis in North America. In the 6 years following the 1999 outbreak, the geographic range and burden of the disease in birds, mosquitoes and humans has greatly expanded to include the 48 contiguous US and 7 Canadian provinces, as well as Mexico, the Caribbean islands and Colombia. WNV has shown an increasing propensity for neuroinvasive disease over the past decade, with varied presentations including meningitis, encephalitis and acute flaccid paralysis. Although neuroinvasive disease occurs in less than 1% of infected individuals, it is associated with high mortality. From 1999–2005, more than 8,000 cases of neuroinvasive WNV disease were reported in the US, resulting in over 780 deaths. In this review, we discuss epidemiology, risk factors, clinical features, diagnosis and prognosis of WNV meningoencephalitis, along with potential treatments. PMID:16932563

  20. Junin virus structural proteins.

    PubMed Central

    De Martínez Segovia, Z M; De Mitri, M I

    1977-01-01

    Polyacrylamide gel electrophoresis of purified Junin virus revealed six distinct structural polypeptides, two major and four minor ones. Four of these polypeptides appeared to be covalently linked with carbohydrate. The molecular weights of the six proteins, estimated by coelectrophoresis with marker proteins, ranged from 25,000 to 91,000. One of the two major components (number 3) was identified as a nucleoprotein and had a molecular weight of 64,000. It was the most prominent protein and was nonglycosylated. The other major protein (number 5), with a molecular weight of 38,000, was a glucoprotein and a component of the viral envelope. The location on the virion of three additional glycopeptides with molecular weights of 91,000, 72,000, and 52,000, together with a protein with a molecular weight of 25,000, was not well defined. PMID:189088

  1. Zika virus infections.

    PubMed

    de Laval, F; Leparc-Goffart, I; Meynard, J-B; Daubigny, H; Simon, F; Briolant, S

    2016-05-01

    Since its discovery in 1947 in Uganda, the Zika virus (ZIKV) remained in the shadows emerging in 2007 in Micronesia, where hundreds of dengue-like syndromes were reported. Then, in 2013-2014, it was rife in French Polynesia, where the first neurological effects were observed. More recently, its arrival in Brazil was accompanied by an unusually high number of children with microcephaly born to mothers infected with ZIKV during the first trimester of pregnancy. In 2016, the World Health Organization declared ZIKV infection to be a public health emergency and now talks about a ZIKV pandemic. This review aims to summarize the current knowledge about ZIKV infection, successively addressing its transmission, epidemiology, clinical aspects, diagnosis, treatment, and prevention before discussing some perspectives.

  2. Varicella-zoster virus.

    PubMed Central

    Arvin, A M

    1996-01-01

    Varicella-zoster virus (VZV) is a ubiquitous human alphaherpesvirus that causes varicella (chicken pox) and herpes zoster (shingles). Varicella is a common childhood illness, characterized by fever, viremia, and scattered vesicular lesions of the skin. As is characteristic of the alphaherpesviruses, VZV establishes latency in cells of the dorsal root ganglia. Herpes zoster, caused by VZV reactivation, is a localized, painful, vesicular rash involving one or adjacent dermatomes. The incidence of herpes zoster increases with age or immunosuppression. The VZV virion consists of a nucleocapsid surrounding a core that contains the linear, double-stranded DNA genome; a protein tegument separates the capsid from the lipid envelope, which incorporates the major viral glycoproteins. VZV is found in a worldwide geographic distribution but is more prevalent in temperate climates. Primary VZV infection elicits immunoglobulin G (IgG), IgM, and IgA antibodies, which bind to many classes of viral proteins. Virus-specific cellular immunity is critical for controlling viral replication in healthy and immunocompromised patients with primary or recurrent VZV infections. Rapid laboratory confirmation of the diagnosis of varicella or herpes zoster, which can be accomplished by detecting viral proteins or DNA, is important to determine the need for antiviral therapy. Acyclovir is licensed for treatment of varicella and herpes zoster, and acyclovir, valacyclovir, and famciclovir are approved for herpes zoster. Passive antibody prophylaxis with varicella-zoster immune globulin is indicated for susceptible high-risk patients exposed to varicella. A live attenuated varicella vaccine (Oka/Merck strain) is now recommended for routine childhood immunization. PMID:8809466

  3. Novel vaccines against influenza viruses

    PubMed Central

    Kang, Sang-Moo; Song, Jae-Min; Compans, Richard W.

    2011-01-01

    Killed and live attenuated influenza virus vaccines are effective in preventing and curbing the spread of influenza epidemics when the strains present in the vaccines are closely matched with the predicted epidemic strains. These vaccines are primarily targeted to induce immunity to the variable major target antigen, hemagglutinin (HA) of influenza virus. However, current vaccines are not effective in preventing the emergence of new pandemic or highly virulent viruses. New approaches are being investigated to develop universal influenza virus vaccines as well as to apply more effective vaccine delivery methods. Conserved vaccine targets including the influenza M2 ion channel protein and HA stalk domains are being developed using recombinant technologies to improve the level of cross protection. In addition, recent studies provide evidence that vaccine supplements can provide avenues to further improve current vaccination. PMID:21968298

  4. Zika virus: An international emergency?

    PubMed

    Palomo, Adolfo Martinez

    2016-05-01

    This Viewpoint discusses the World Health Organization's Declaration on 1 February 2016 that the epidemic infection caused by the Zika virus is a public health emergency of international concern - the basis of the decision and controversy surrounding it.

  5. About Human Parainfluenza Viruses (HPIVs)

    MedlinePlus

    ... Overview Laboratory Diagnosis HPIV Seasons Resources & References About Human Parainfluenza Viruses (HPIVs) Recommend on Facebook Tweet Share ... 6348 Email CDC-INFO U.S. Department of Health & Human Services HHS/Open USA.gov Top

  6. Viruses of eukaryotice green algae

    SciTech Connect

    Van Etten, J.L.

    1989-01-01

    The primary objective of our research was to develop the Chlorella-PBCV-1 virus system so that it can be used as a model system for studying gene expression in a photosynthetic eukaryote. We have made considerable progress and have learned much about PBCV-1 and its replication cycle. In addition, several significant discoveries were made in the last 3 to 4 years. These discoveries include: (i) the finding that morphologically similar, plaque forming, dsDNA containing viruses are common in nature and can be isolated readily from fresh water, (ii) the finding that all of these Chlorella viruses contain methylated bases which range in concentration from 0.1% to 47.5% m{sup 5}dC and 0 to 37% m{sup 6}dA and (iii) the discovery that infection with at least some of these viruses induces the appearance of DNA modification/restriction systems. 26 refs.

  7. Herpes Simplex Virus (Cold Sores)

    MedlinePlus

    ... the skin, eyes, and mouth. This is a life-threatening infection that can lead to permanent brain damage or even death. Herpes simplex viruses also cause encephalitis, an infection of the brain. ...

  8. Arthropod viruses and small RNAs.

    PubMed

    Vijayendran, Diveena; Airs, Paul M; Dolezal, Kelly; Bonning, Bryony C

    2013-10-01

    The recently characterized small RNAs provide a new paradigm for physiological studies. These molecules have been shown to be integral players in processes as diverse as development and innate immunity against bacteria and viruses in eukaryotes. Several of the well-characterized small RNAs including small interfering RNAs, microRNAs and PIWI-interacting RNAs are emerging as important players in mediating arthropod host-virus interactions. Understanding the role of small RNAs in arthropod host-virus molecular interactions will facilitate manipulation of these pathways for both management of arthropod pests of agricultural and medical importance, and for protection of beneficial arthropods such as honey bees and shrimp. This review highlights recent research on the role of small RNAs in arthropod host-virus interactions with reference to other host-pathogen systems. PMID:23932976

  9. Peste des Petits Ruminants Virus.

    PubMed

    Baron, M D; Diallo, A; Lancelot, R; Libeau, G

    2016-01-01

    Peste des petits ruminants virus (PPRV) causes a severe contagious disease of sheep and goats and has spread extensively through the developing world. Because of its disproportionately large impact on the livelihoods of low-income livestock keepers, and the availability of effective vaccines and good diagnostics, the virus is being targeted for global control and eventual eradication. In this review we examine the origin of the virus and its current distribution, and the factors that have led international organizations to conclude that it is eradicable. We also review recent progress in the molecular and cellular biology of the virus and consider areas where further research is required to support the efforts being made by national, regional, and international bodies to tackle this growing threat. PMID:27112279

  10. An overview of Chikungunya virus.

    PubMed

    Busch, Mitchell; Erickson, Gerald

    2015-10-01

    Chikungunya fever is a viral infection caused by the Chikungunya virus that causes abrupt onset of fever, debilitating arthralgias and myalgias, and some rare but serious atypical presentations in infected patients. This mosquito-borne virus may not be familiar to North American healthcare providers. This article describes the causes, epidemiology, pathophysiology, clinical presentation, diagnostic and screening measures, management guidelines, and future research prospects for Chikungunya infection.

  11. Lack of correlation between the resistances to two rhabdovirus infections in rainbow trout.

    PubMed

    Verrier, Eloi R; Ehanno, Aude; Biacchesi, Stéphane; Le Guillou, Sandrine; Dechamp, Nicolas; Boudinot, Pierre; Bremont, Michel; Quillet, Edwige

    2013-07-01

    The Viral Hemorrhagic Septicemia Virus (VHSV) and the Infectious Hematopoietic Necrosis Virus (IHNV) are two rhabdoviruses responsible for serious outbreaks in salmonid farms. To date, little is known about the variability of host response to these viruses. Using gynogenetic clonal lines of rainbow trout exhibiting a wide range of resistance to viral infections, we showed that there was no correlation between the resistance to VHSV and IHNV. We also confirmed the importance of fish weight for its susceptibility to IHNV infection. Finally, using a chimeric recombinant IHNV expressing the VHSV glycoprotein, we showed that the glycoprotein plays a key role in the virulence and in the level of resistance observed in different genetic backgrounds. Taken together, our results provide new prospects for a better understanding of host responses to rhabdovirus infections in salmonids.

  12. Early Activation of Teleost B Cells in Response to Rhabdovirus Infection

    PubMed Central

    Abós, Beatriz; Castro, Rosario; González Granja, Aitor; Havixbeck, Jeffrey J.; Barreda, Daniel R.

    2014-01-01

    ABSTRACT To date, the response of teleost B cells to specific pathogens has been only scarcely addressed. In this work, we have demonstrated that viral hemorrhagic septicemia virus (VHSV), a fish rhabdovirus, has the capacity to infect rainbow trout spleen IgM-positive (IgM+) cells, although the infection is not productive. Consequently, we have studied the effects of VHSV on IgM+ cell functionality, comparing these effects to those elicited by a Toll-like receptor 3 (TLR3) ligand, poly(I·C). We found that poly(I·C) and VHSV significantly upregulated TLR3 and type I interferon (IFN) transcription in spleen and blood IgM+ cells. Further effects included the upregulated transcription of the CK5B chemokine. The significant inhibition of some of these effects in the presence of bafilomycin A1 (BAF), an inhibitor of endosomal acidification, suggests the involvement of an intracellular TLR in these responses. In the case of VHSV, these transcriptional effects were dependent on viral entry into B cells and the initiation of viral transcription. VHSV also provoked the activation of NF-κB and the upregulation of major histocompatibility complex class II (MHC-II) cell surface expression on IgM+ cells, which, along with the increased transcription of the costimulatory molecules CD80/86 and CD83, pointed to VHSV-induced IgM+ cell activation toward an antigen-presenting profile. Finally, despite the moderate effects of VHSV on IgM+ cell proliferation, a consistent effect on IgM+ cell survival was detected. IMPORTANCE Innate immune responses to pathogens established through their recognition by pattern recognition receptors (PRRs) have been traditionally ascribed to innate cells. However, recent evidence in mammals has revealed that innate pathogen recognition by B lymphocytes is a crucial factor in shaping the type of immune response that is mounted. In teleosts, these immediate effects of viral encounter on B lymphocytes have not been addressed to date. In our study, we

  13. A DNA Virus of Drosophila

    PubMed Central

    Unckless, Robert L.

    2011-01-01

    Little is known about the viruses infecting most species. Even in groups as well-studied as Drosophila, only a handful of viruses have been well-characterized. A viral metagenomic approach was used to explore viral diversity in 83 wild-caught Drosophila innubila, a mushroom feeding member of the quinaria group. A single fly that was injected with, and died from, Drosophila C Virus (DCV) was added to the sample as a control. Two-thirds of reads in the infected sample had DCV as the best BLAST hit, suggesting that the protocol developed is highly sensitive. In addition to the DCV hits, several sequences had Oryctes rhinoceros Nudivirus, a double-stranded DNA virus, as a best BLAST hit. The virus associated with these sequences was termed Drosophila innubila Nudivirus (DiNV). PCR screens of natural populations showed that DiNV was both common and widespread taxonomically and geographically. Electron microscopy confirms the presence of virions in fly fecal material similar in structure to other described Nudiviruses. In 2 species, D. innubila and D. falleni, the virus is associated with a severe (∼80–90%) loss of fecundity and significantly decreased lifespan. PMID:22053195

  14. Another really, really big virus.

    PubMed

    Van Etten, James L

    2011-01-01

    Viruses with genomes larger than 300 kb and up to 1.2 Mb, which encode hundreds of proteins, are being discovered and characterized with increasing frequency. Most, but not all, of these large viruses (often referred to as giruses) infect protists that live in aqueous environments. Bioinformatic analyses of metagenomes of aqueous samples indicate that large DNA viruses are quite common in nature and await discovery. One issue that is perhaps not appreciated by the virology community is that large viruses, even those classified in the same family, can differ significantly in morphology, lifestyle, and gene complement. This brief commentary, which will mention some of these unique properties, was stimulated by the characterization of the newest member of this club, virus CroV (Fischer, M.G.; Allen, M.J.; Wilson, W.H.; Suttle, C.A. Giant virus with a remarkable complement of genes infects marine zooplankton. Proc. Natl. Acad. Sci. USA 2010, 107, 19508-19513). CroV has a 730 kb genome (with ∼544 protein-encoding genes) and infects the marine microzooplankton Cafeteria roenbergensis producing a lytic infection.

  15. Kinetics of virus production from single cells.

    PubMed

    Timm, Andrea; Yin, John

    2012-03-01

    The production of virus by infected cells is an essential process for the spread and persistence of viral diseases, the effectiveness of live-viral vaccines, and the manufacture of viruses for diverse applications. Yet despite its importance, methods to precisely measure virus production from cells are lacking. Most methods test infected-cell populations, masking how individual cells behave. Here we measured the kinetics of virus production from single cells. We combined simple steps of liquid-phase infection, serial dilution, centrifugation, and harvesting, without specialized equipment, to track the production of virus particles from BHK cells infected with vesicular stomatitis virus. Remarkably, cell-to-cell differences in latent times to virus release were within a factor of two, while production rates and virus yields spanned over 300-fold, highlighting an extreme diversity in virus production for cells from the same population. These findings have fundamental and technological implications for health and disease.

  16. PC viruses: How do they do that

    SciTech Connect

    Pichnarczyk, K.

    1992-07-01

    The topic of PC Viruses has been an issue for a number of years now. They've been reported in every major newspaper, tabloids, television and radio. People from all fields get viruses: government, private sector businesses, home computers, schools, computer software suppliers. A definition is proposed to introduce the virus phenomenon. Virus authors come from a variety of communities. Motives and ideologies of authors are discussed, and examples of viruses are offered. Also mentioned is the growing number of viruses developed, isolated, and never distributed to the public at large, but kept within the antivirus research community. Virus examples are offered as well. Viruses are distributed not only through bulletin boards and shareware, but also from areas previously assumed to be safe, including the threat of receiving a virus through a standard in-house function, such as an in-house hardware maintenance shop. Three categories of viruses are presented: File Infecter viruses, Boot Sector Infecters, and the new category of Directory Entry Infecter virus. Also discussed are crossover viruses, that is, viruses which utilize a variety of techniques to ensure survival. An explanation of what is occurring within every stage of various viruses is given. Replication strategies common to all three types is noted, mainly the two different replication strategies of memory resident infecters and active selection infecters. A detailed definition, description and application of a stealth virus is presented. Detection strategies are discussed as each topic in this section is completed; a high level schemata of the operation of various virus detection programs ispresented. Since most eradication today is done using virus detection/eradication software, this paper attempts to reveal the techniques used by these packages.Included in the paper is the topic of manual eradication.

  17. PC viruses: How do they do that?

    SciTech Connect

    Pichnarczyk, K.

    1992-07-01

    The topic of PC Viruses has been an issue for a number of years now. They`ve been reported in every major newspaper, tabloids, television and radio. People from all fields get viruses: government, private sector businesses, home computers, schools, computer software suppliers. A definition is proposed to introduce the virus phenomenon. Virus authors come from a variety of communities. Motives and ideologies of authors are discussed, and examples of viruses are offered. Also mentioned is the growing number of viruses developed, isolated, and never distributed to the public at large, but kept within the antivirus research community. Virus examples are offered as well. Viruses are distributed not only through bulletin boards and shareware, but also from areas previously assumed to be safe, including the threat of receiving a virus through a standard in-house function, such as an in-house hardware maintenance shop. Three categories of viruses are presented: File Infecter viruses, Boot Sector Infecters, and the new category of Directory Entry Infecter virus. Also discussed are crossover viruses, that is, viruses which utilize a variety of techniques to ensure survival. An explanation of what is occurring within every stage of various viruses is given. Replication strategies common to all three types is noted, mainly the two different replication strategies of memory resident infecters and active selection infecters. A detailed definition, description and application of a stealth virus is presented. Detection strategies are discussed as each topic in this section is completed; a high level schemata of the operation of various virus detection programs ispresented. Since most eradication today is done using virus detection/eradication software, this paper attempts to reveal the techniques used by these packages.Included in the paper is the topic of manual eradication.

  18. Methods for engineering resistance to plant viruses.

    PubMed

    Sudarshana, Mysore R; Roy, Gourgopal; Falk, Bryce W

    2007-01-01

    The development of genetically engineered resistance to plant viruses is a result of efforts to understand the plant-virus interactions involved in "crossprotection," a phenomenon observed with several plant virus diseases. Historically, expression of the coat protein gene of Tobacco mosaic virus in transgenic tobacco (Nicotiana tabacum) plants is the first example of transgene-mediated resistance to a plant virus. Subsequently, virus-derived sequences of several plant viruses were shown to confer virus resistance in experimental and/or natural hosts. For plant RNA viruses, virus complementary DNA sequences shown to confer resistance include wild-type genes, mutated genes that produced truncated protein products, and nontranslatable sense or antisense transcripts to various regions of the virus genome. Resistance also has been demonstrated for some viruses by mutant trans-dominant gene products, derived from the movement protein and replication-associated protein genes. In addition to virus-derived sequences, gene sequences of plant origin have also been used for transgenic resistance, and such resistance can be virus-specific, for instance, R genes isolated from resistant plant genotypes, or nonspecific, for example, ribosome inactivating proteins and proteinase inhibitors. Plantibodies and 2-5A synthetase, a class of proteins of mammalian origin, have also been useful in engineering plant virus resistance. In the case of transgenic resistance mediated by viral coat protein, the mechanism of resistance was suggested to operate during the early events of virus infection. However, transgene-mediated RNA silencing and generation of small interfering RNAs appears to be the primary mechanism that confers resistance to plant viruses. Despite the advantages of transgene-mediated resistance, current interest in the development and use of transgenic virus resistant plants is low in most parts of the world. However, because of its real potential, we believe that this

  19. Emerging influenza viruses and the prospect of a universal influenza virus vaccine.

    PubMed

    Krammer, Florian

    2015-05-01

    Influenza viruses cause annual seasonal epidemics and pandemics at irregular intervals. Several cases of human infections with avian and swine influenza viruses have been detected recently, warranting enhanced surveillance and the development of more effective countermeasures to address the pandemic potential of these viruses. The most effective countermeasure against influenza virus infection is the use of prophylactic vaccines. However, vaccines that are currently in use for seasonal influenza viruses have to be re-formulated and re-administered in a cumbersome process every year due to the antigenic drift of the virus. Furthermore, current seasonal vaccines are ineffective against novel pandemic strains. This paper reviews zoonotic influenza viruses with pandemic potential and technological advances towards better vaccines that induce broad and long lasting protection from influenza virus infection. Recent efforts have focused on the development of broadly protective/universal influenza virus vaccines that can provide immunity against drifted seasonal influenza virus strains but also against potential pandemic viruses.

  20. Circulating avian influenza viruses closely related to the 1918 virus have pandemic potential.

    PubMed

    Watanabe, Tokiko; Zhong, Gongxun; Russell, Colin A; Nakajima, Noriko; Hatta, Masato; Hanson, Anthony; McBride, Ryan; Burke, David F; Takahashi, Kenta; Fukuyama, Satoshi; Tomita, Yuriko; Maher, Eileen A; Watanabe, Shinji; Imai, Masaki; Neumann, Gabriele; Hasegawa, Hideki; Paulson, James C; Smith, Derek J; Kawaoka, Yoshihiro

    2014-06-11

    Wild birds harbor a large gene pool of influenza A viruses that have the potential to cause influenza pandemics. Foreseeing and understanding this potential is important for effective surveillance. Our phylogenetic and geographic analyses revealed the global prevalence of avian influenza virus genes whose proteins differ only a few amino acids from the 1918 pandemic influenza virus, suggesting that 1918-like pandemic viruses may emerge in the future. To assess this risk, we generated and characterized a virus composed of avian influenza viral segments with high homology to the 1918 virus. This virus exhibited pathogenicity in mice and ferrets higher than that in an authentic avian influenza virus. Further, acquisition of seven amino acid substitutions in the viral polymerases and the hemagglutinin surface glycoprotein conferred respiratory droplet transmission to the 1918-like avian virus in ferrets, demonstrating that contemporary avian influenza viruses with 1918 virus-like proteins may have pandemic potential. PMID:24922572

  1. Circulating avian influenza viruses closely related to the 1918 virus have pandemic potential

    PubMed Central

    Watanabe, Tokiko; Zhong, Gongxun; Russell, Colin A.; Nakajima, Noriko; Hatta, Masato; Hanson, Anthony; McBride, Ryan; Burke, David F.; Takahashi, Kenta; Fukuyama, Satoshi; Tomita, Yuriko; Maher, Eileen A.; Watanabe, Shinji; Imai, Masaki; Neumann, Gabriele; Hasegawa, Hideki; Paulson, James C.; Smith, Derek J.; Kawaoka, Yoshihiro

    2014-01-01

    Summary Wild birds harbor a large gene pool of influenza A viruses that have the potential to cause influenza pandemics. Foreseeing and understanding this potential is important for effective surveillance. Our phylogenetic and geographic analyses revealed the global prevalence of avian influenza virus genes whose proteins differ only a few amino acids from the 1918 pandemic influenza virus, suggesting that 1918-like pandemic viruses may emerge in the future. To assess this risk, we generated and characterized a virus composed of avian influenza viral segments with high homology to the 1918 virus. This virus exhibited higher pathogenicity in mice and ferrets than an authentic avian influenza virus. Further, acquisition of seven amino acid substitutions in the viral polymerases and the hemagglutinin surface glycoprotein conferred respiratory droplet transmission to the 1918-like avian virus in ferrets, demonstrating that contemporary avian influenza viruses with 1918 virus-like proteins may have pandemic potential. PMID:24922572

  2. Zika Virus Infection and Zika Fever: Frequently Asked Questions

    MedlinePlus

    ... Updated: 25 March 2016 ABOUT ZIKA What is Zika virus infection? Zika virus infection is caused by the ... possible to characterize the disease better. How is Zika virus transmitted? Zika virus is transmitted to people through ...

  3. Quantitative nanoscale electrostatics of viruses

    NASA Astrophysics Data System (ADS)

    Hernando-Pérez, M.; Cartagena-Rivera, A. X.; Lošdorfer Božič, A.; Carrillo, P. J. P.; San Martín, C.; Mateu, M. G.; Raman, A.; Podgornik, R.; de Pablo, P. J.

    2015-10-01

    Electrostatics is one of the fundamental driving forces of the interaction between biomolecules in solution. In particular, the recognition events between viruses and host cells are dominated by both specific and non-specific interactions and the electric charge of viral particles determines the electrostatic force component of the latter. Here we probe the charge of individual viruses in liquid milieu by measuring the electrostatic force between a viral particle and the Atomic Force Microscope tip. The force spectroscopy data of co-adsorbed φ29 bacteriophage proheads and mature virions, adenovirus and minute virus of mice capsids is utilized for obtaining the corresponding density of charge for each virus. The systematic differences of the density of charge between the viral particles are consistent with the theoretical predictions obtained from X-ray structural data. Our results show that the density of charge is a distinguishing characteristic of each virus, depending crucially on the nature of the viral capsid and the presence/absence of the genetic material.Electrostatics is one of the fundamental driving forces of the interaction between biomolecules in solution. In particular, the recognition events between viruses and host cells are dominated by both specific and non-specific interactions and the electric charge of viral particles determines the electrostatic force component of the latter. Here we probe the charge of individual viruses in liquid milieu by measuring the electrostatic force between a viral particle and the Atomic Force Microscope tip. The force spectroscopy data of co-adsorbed φ29 bacteriophage proheads and mature virions, adenovirus and minute virus of mice capsids is utilized for obtaining the corresponding density of charge for each virus. The systematic differences of the density of charge between the viral particles are consistent with the theoretical predictions obtained from X-ray structural data. Our results show that the density of

  4. Unusual Influenza A Viruses in Bats

    PubMed Central

    Mehle, Andrew

    2014-01-01

    Influenza A viruses infect a remarkably diverse number of hosts. Two completely new influenza A virus subtypes were recently discovered in bats, dramatically expanding the host range of the virus. These bat viruses are extremely divergent from all other known strains and likely have unique replication cycles. Phylogenetic analysis indicates long-term, isolated evolution in bats. This is supported by a high seroprevalence in sampled bat populations. As bats represent ~20% of all classified mammals, these findings suggests the presence of a massive cryptic reservoir of poorly characterized influenza A viruses. Here, we review the exciting progress made on understanding these newly discovered viruses, and discuss their zoonotic potential. PMID:25256392

  5. Epidemiology of viral hemorrhagic septicemia (VHS) among juvenile Pacific herring and Pacific sandlances in Puget Sound, Washington

    USGS Publications Warehouse

    Kocan, R.M.; Hershberger, P.K.; Elder, N.E.; Winton, J.R.

    2001-01-01

    Viral hemorrhagic septicemia (VHS) and the associated virus (VHSV) were identified in newly metamorphosed Pacific herring Clupea pallasi and Pacific sand lances Ammodytes hexapterus captured from Puget Sound, Washington, between 1995 and 1998. During that 4-year period, virus was detected in less than 1% of free-ranging, age-0 Pacific herring; however, when groups of these fish were confined in the laboratory, they experienced severe mortality, occasionally exceeding 50%, with the prevalence of VHSV reaching 100% by 14 d postcapture. At 7–21 d postcapture, VHSV titers peaked in excess of 108 plaque-forming units/g of tissue; by 30 d postcapture, however, the virus could no longer be isolated. Fish surviving beyond 30 d eliminated the virus from their tissues, but some remained lethargic and continued to show signs of hemorrhage around the mouth, skin, and fins until about 6 weeks postcapture. No cutaneous ulcers were observed during either the acute or the recovery phases of infection. Eighteen-month-old Pacific herring captured from the same area were also negative for VHSV but developed active infections after confinement for 7 d. Unlike younger fish, only 8.4% of these older fish died of VHS, and 7.7% of survivors were positive for VHSV at 7–10 d postcapture, which suggests that a higher proportion of the older fish had developed resistance to VHSV from prior exposure to it. Three months after fatalities ceased in the laboratory-held fish, the surviving fish were challenged with 5 3 103 plaque-forming units/mL of VHSV for 1 h. No mortality was observed during the next 30 d, and virus was recoverable at very low titers in fewer than 5% of the challenged fish, indicating the development of an active immunity to VHSV. Laboratory cohabitation of infected wild Pacific herring with laboratory-reared, specific-pathogen-free Pacific herring resulted in transmission of VHSV to the nonimmune fish, with the resulting course of disease resembling that seen in wild

  6. Cell entry of enveloped viruses.

    PubMed

    Cosset, François-Loic; Lavillette, Dimitri

    2011-01-01

    Enveloped viruses penetrate their cell targets following the merging of their membrane with that of the cell. This fusion process is catalyzed by one or several viral glycoproteins incorporated on the membrane of the virus. These envelope glycoproteins (EnvGP) evolved in order to combine two features. First, they acquired a domain to bind to a specific cellular protein, named "receptor." Second, they developed, with the help of cellular proteins, a function of finely controlled fusion to optimize the replication and preserve the integrity of the cell, specific to the genus of the virus. Following the activation of the EnvGP either by binding to their receptors and/or sometimes the acid pH of the endosomes, many changes of conformation permit ultimately the action of a specific hydrophobic domain, the fusion peptide, which destabilizes the cell membrane and leads to the opening of the lipidic membrane. The comprehension of these mechanisms is essential to develop medicines of the therapeutic class of entry inhibitor like enfuvirtide (Fuzeon) against human immunodeficiency virus (HIV). In this chapter, we will summarize the different envelope glycoprotein structures that viruses develop to achieve membrane fusion and the entry of the virus. We will describe the different entry pathways and cellular proteins that viruses have subverted to allow infection of the cell and the receptors that are used. Finally, we will illustrate more precisely the recent discoveries that have been made within the field of the entry process, with a focus on the use of pseudoparticles. These pseudoparticles are suitable for high-throughput screenings that help in the development of natural or artificial inhibitors as new therapeutics of the class of entry inhibitors.

  7. Marek's disease virus latency.

    PubMed

    Morgan, R W; Xie, Q; Cantello, J L; Miles, A M; Bernberg, E L; Kent, J; Anderson, A

    2001-01-01

    MDV latency is defined as the persistence of the viral genome in the absence of production of infectious virus except during reactivation. A number of systems for studying MDV latency exist, and most involve the use of lymphoblastoid cells or tumors. It has been difficult to divorce latency and transformation. Understanding the relationship between these two states remains a major challenge for the MDV system. Based on their patterns of expression, the MDV LATs are apt to be important in the balance between latent and lytic infections. The LATs are a complex group of transcripts. The profile of gene expression that characterizes latency differs among all herpesviruses, and MDV is no exception. MDV LATs bear little resemblance to LATs of other alphaherpesviruses or to the LATs of other lymphotropic herpesviruses. LAT splicing patterns are complex and the relationships among various spliced species or between these species and the large 10-kb transcript are unknown. In addition, the existence of any protein gene products of significance is unknown at this time. More work is needed to further investigate the significance and function of these RNAs. Better technology to construct mutants in the MDV system is badly needed, since the analysis of mutants in the chicken is a powerful and unique advantage of the MDV system. PMID:11217424

  8. Usutu virus in Africa.

    PubMed

    Nikolay, Birgit; Diallo, Mawlouth; Boye, Cheikh Saad Bouh; Sall, Amadou Alpha

    2011-11-01

    Usutu virus (USUV) was discovered in South Africa in 1959. Since then, it has been reported in several African countries including Senegal, Central African Republic, Nigeria, Uganda, Burkina Faso, Cote d'Ivoire, and Morocco. In 2001, USUV has been identified for the first time outside of Africa, namely in Europe, where it caused a significant mortality among blackbirds in Vienna, Austria. In 2009, the first two human cases of USUV infection in Europe have been reported in Italy, causing encephalitis in immunocompromised patients. The host range in Africa includes mainly Culex mosquitoes, birds, and also humans with one benign and one severe case. Given its role as a potential human pathogen and the similar appearance compared with other emerging arboviruses, it is essential to investigate the natural history and ecology of USUV in Africa. In this regard, we review the emergence of USUV in Africa, summarizing data about isolations, host range, and potential vectors, which should help to improve our understanding of the factors underlying the circulation of USUV in Europe and Africa. PMID:21767160

  9. Dengue viruses - an overview.

    PubMed

    Bäck, Anne Tuiskunen; Lundkvist, Ake

    2013-01-01

    Dengue viruses (DENVs) cause the most common arthropod-borne viral disease in man with 50-100 million infections per year. Because of the lack of a vaccine and antiviral drugs, the sole measure of control is limiting the Aedes mosquito vectors. DENV infection can be asymptomatic or a self-limited, acute febrile disease ranging in severity. The classical form of dengue fever (DF) is characterized by high fever, headache, stomach ache, rash, myalgia, and arthralgia. Severe dengue, dengue hemorrhagic fever (DHF), and dengue shock syndrome (DSS) are accompanied by thrombocytopenia, vascular leakage, and hypotension. DSS, which can be fatal, is characterized by systemic shock. Despite intensive research, the underlying mechanisms causing severe dengue is still not well understood partly due to the lack of appropriate animal models of infection and disease. However, even though it is clear that both viral and host factors play important roles in the course of infection, a fundamental knowledge gap still remains to be filled regarding host cell tropism, crucial host immune response mechanisms, and viral markers for virulence.

  10. Stochastic analysis of virus transport in aquifers

    USGS Publications Warehouse

    Campbell, Rehmann L.L.; Welty, C.; Harvey, R.W.

    1999-01-01

    A large-scale model of virus transport in aquifers is derived using spectral perturbation analysis. The effects of spatial variability in aquifer hydraulic conductivity and virus transport (attachment, detachment, and inactivation) parameters on large-scale virus transport are evaluated. A stochastic mean model of virus transport is developed by linking a simple system of local-scale free-virus transport and attached-virus conservation equations from the current literature with a random-field representation of aquifer and virus transport properties. The resultant mean equations for free and attached viruses are found to differ considerably from the local-scale equations on which they are based and include effects such as a free-virus effective velocity that is a function of aquifer heterogeneity as well as virus transport parameters. Stochastic mean free-virus breakthrough curves are compared with local model output in order to observe the effects of spatial variability on mean one-dimensional virus transport in three-dimensionally heterogeneous porous media. Significant findings from this theoretical analysis include the following: (1) Stochastic model breakthrough occurs earlier than local model breakthrough, and this effect is most pronounced for the least conductive aquifers studied. (2) A high degree of aquifer heterogeneity can lead to virus breakthrough actually preceding that of a conservative tracer. (3) As the mean hydraulic conductivity is increased, the mean model shows less sensitivity to the variance of the natural-logarithm hydraulic conductivity and mean virus diameter. (4) Incorporation of a heterogeneous colloid filtration term results in higher predicted concentrations than a simple first-order adsorption term for a given mean attachment rate. (5) Incorporation of aquifer heterogeneity leads to a greater range of virus diameters for which significant breakthrough occurs. (6) The mean model is more sensitive to the inactivation rate of viruses

  11. Acute otitis media and respiratory virus infections.

    PubMed

    Ruuskanen, O; Arola, M; Putto-Laurila, A; Mertsola, J; Meurman, O; Viljanen, M K; Halonen, P

    1989-02-01

    We studied the association of acute otitis media with different respiratory virus infections in a pediatric department on the basis of epidemics between 1980 and 1985. Altogether 4524 cases of acute otitis media were diagnosed. The diagnosis was confirmed by tympanocentesis in 3332 ears. Respiratory virus infection was diagnosed during the same period in 989 patients by detecting viral antigen in nasopharyngeal mucus. There was a significant correlation between acute otitis media and respiratory virus epidemics, especially respiratory syncytial virus epidemics. There was no significant correlation between outbreaks of other respiratory viruses and acute otitis media. Acute otitis media was diagnosed in 57% of respiratory syncytial virus, 35% of influenza A virus, 33% of parainfluenza type 3 virus, 30% of adenovirus, 28% of parainfluenza type 1 virus, 18% of influenza B virus and 10% of parainfluenza type 2 virus infections. These observations show a clear association of respiratory virus infections with acute otitis media. In this study on hospitalized children Haemophilus influenzae strains were the most common bacteriologic pathogens in middle ear fluid, occurring in 19% of cases. Streptococcus pneumoniae was present in 16% and Branhamella catarrhalis in 7% of cases. There was no association between specific viruses and bacteria observed in this study.

  12. Viruses and viruslike particles of eukaryotic algae.

    PubMed Central

    Van Etten, J L; Lane, L C; Meints, R H

    1991-01-01

    Until recently there was little interest or information on viruses and viruslike particles of eukaryotic algae. However, this situation is changing. In the past decade many large double-stranded DNA-containing viruses that infect two culturable, unicellular, eukaryotic green algae have been discovered. These viruses can be produced in large quantities, assayed by plaque formation, and analyzed by standard bacteriophage techniques. The viruses are structurally similar to animal iridoviruses, their genomes are similar to but larger (greater than 300 kbp) than that of poxviruses, and their infection process resembles that of bacteriophages. Some of the viruses have DNAs with low levels of methylated bases, whereas others have DNAs with high concentrations of 5-methylcytosine and N6-methyladenine. Virus-encoded DNA methyltransferases are associated with the methylation and are accompanied by virus-encoded DNA site-specific (restriction) endonucleases. Some of these enzymes have sequence specificities identical to those of known bacterial enzymes, and others have previously unrecognized specificities. A separate rod-shaped RNA-containing algal virus has structural and nucleotide sequence affinities to higher plant viruses. Quite recently, viruses have been associated with rapid changes in marine algal populations. In the next decade we envision the discovery of new algal viruses, clarification of their role in various ecosystems, discovery of commercially useful genes in these viruses, and exploitation of algal virus genetic elements in plant and algal biotechnology. Images PMID:1779928

  13. Plasmodesmata: channels for viruses on the move.

    PubMed

    Heinlein, Manfred

    2015-01-01

    The symplastic communication network established by plasmodesmata (PD) and connected phloem provides an essential pathway for spatiotemporal intercellular signaling in plant development but is also exploited by viruses for moving their genomes between cells in order to infect plants systemically. Virus movement depends on virus-encoded movement proteins (MPs) that target PD and therefore represent important keys to the cellular mechanisms underlying the intercellular trafficking of viruses and other macromolecules. Viruses and their MPs have evolved different mechanisms for intracellular transport and interaction with PD. Some viruses move from cell to cell by interacting with cellular mechanisms that control the size exclusion limit of PD whereas other viruses alter the PD architecture through assembly of specialized transport structures within the channel. Some viruses move between cells in the form of assembled virus particles whereas other viruses may interact with nucleic acid transport mechanisms to move their genomes in a non-encapsidated form. Moreover, whereas several viruses rely on the secretory pathway to target PD, other viruses interact with the cortical endoplasmic reticulum and associated cytoskeleton to spread infection. This chapter provides an introduction into viruses and their role in studying the diverse cellular mechanisms involved in intercellular PD-mediated macromolecular trafficking.

  14. Autophagic machinery activated by dengue virus enhances virus replication

    SciTech Connect

    Lee, Y.-R.; Lei, H.-Y.; Liu, M.-T.; Wang, J.-R.; Chen, S.-H.; Jiang-Shieh, Y.-F.; Lin, Y.-S.; Yeh, T.-M.; Liu, C.-C.; Liu, H.-S.

    2008-05-10

    Autophagy is a cellular response against stresses which include the infection of viruses and bacteria. We unravel that Dengue virus-2 (DV2) can trigger autophagic process in various infected cell lines demonstrated by GFP-LC3 dot formation and increased LC3-II formation. Autophagosome formation was also observed under the transmission electron microscope. DV2-induced autophagy further enhances the titers of extracellular and intracellular viruses indicating that autophagy can promote viral replication in the infected cells. Moreover, our data show that ATG5 protein is required to execute DV2-induced autophagy. All together, we are the first to demonstrate that DV can activate autophagic machinery that is favorable for viral replication.

  15. Polypeptide composition of spleen necrosis virus, a reticuloendotheliosis virus.

    PubMed Central

    Mosser, A G

    1975-01-01

    The polypeptide composition of virions of spleen necrosis virus, a reticuloendotheliosis virus, was determined using electrophoresis on sodium dodecyl sulfate-containing, 10 percent polyacrylamide gels. Ten polypeptides were resolved. Four of these were present in minor and somewhat variable amounts. Two proteins, gp71 and gp22, contained D-glucosamine and were located on the outer surface of the lipid envelope, as demonstrated by lactoperoxidase-catalyzed iodination and by bromelain digestion. The results suggest that two of the minor proteins, p36 and p26, were also located on the outer surface, although they lacked D-glucosamine. Treatment of the virus with 0.25 percent Nonidet P-40 and 1 percent dithiothreitol produced a subparticle with a buoyant density of approximately 1.31 g/cm-3. This particle was relatively enriched with polypeptides p77, p62, and p50 and contained small amounts of three other polypeptides. PMID:1142473

  16. [Bats and Viruses: complex relationships].

    PubMed

    Rodhain, F

    2015-10-01

    With more than 1 200 species, bats and flying foxes (Order Chiroptera) constitute the most important and diverse order of Mammals after Rodents. Many species of bats are insectivorous while others are frugivorous and few of them are hematophagous. Some of these animals fly during the night, others are crepuscular or diurnal. Some fly long distances during seasonal migrations. Many species are colonial cave-dwelling, living in a rather small home range while others are relatively solitary. However, in spite of the importance of bats for terrestrial biotic communities and ecosystem ecology, the diversity in their biology and lifestyles remain poorly known and underappreciated. More than sixty viruses have been detected or isolated in bats; these animals are therefore involved in the natural cycles of many of them. This is the case, for instance, of rabies virus and other Lyssavirus (Family Rhabdoviridae), Nipah and Hendra viruses (Paramyxoviridae), Ebola and Marburg viruses (Filoviridae), SARS-CoV and MERS-CoV (Coronaviridae). For these zoonotic viruses, a number of bat species are considered as important reservoir hosts, efficient disseminators or even directly responsible of the transmission. Some of these bat-borne viruses cause highly pathogenic diseases while others are of potential significance for humans and domestic or wild animals; so, bats are an important risk in human and animal public health. Moreover, some groups of viruses developed through different phylogenetic mechanisms of coevolution between viruses and bats. The fact that most of these viral infections are asymptomatic in bats has been observed since a long time but the mechanisms of the viral persistence are not clearly understood. The various bioecology of the different bat populations allows exchange of virus between migrating and non-migrating conspecific species. For a better understanding of the role of bats in the circulation of these viral zoonoses, epidemiologists must pay attention to

  17. [Bats and Viruses: complex relationships].

    PubMed

    Rodhain, F

    2015-10-01

    With more than 1 200 species, bats and flying foxes (Order Chiroptera) constitute the most important and diverse order of Mammals after Rodents. Many species of bats are insectivorous while others are frugivorous and few of them are hematophagous. Some of these animals fly during the night, others are crepuscular or diurnal. Some fly long distances during seasonal migrations. Many species are colonial cave-dwelling, living in a rather small home range while others are relatively solitary. However, in spite of the importance of bats for terrestrial biotic communities and ecosystem ecology, the diversity in their biology and lifestyles remain poorly known and underappreciated. More than sixty viruses have been detected or isolated in bats; these animals are therefore involved in the natural cycles of many of them. This is the case, for instance, of rabies virus and other Lyssavirus (Family Rhabdoviridae), Nipah and Hendra viruses (Paramyxoviridae), Ebola and Marburg viruses (Filoviridae), SARS-CoV and MERS-CoV (Coronaviridae). For these zoonotic viruses, a number of bat species are considered as important reservoir hosts, efficient disseminators or even directly responsible of the transmission. Some of these bat-borne viruses cause highly pathogenic diseases while others are of potential significance for humans and domestic or wild animals; so, bats are an important risk in human and animal public health. Moreover, some groups of viruses developed through different phylogenetic mechanisms of coevolution between viruses and bats. The fact that most of these viral infections are asymptomatic in bats has been observed since a long time but the mechanisms of the viral persistence are not clearly understood. The various bioecology of the different bat populations allows exchange of virus between migrating and non-migrating conspecific species. For a better understanding of the role of bats in the circulation of these viral zoonoses, epidemiologists must pay attention to

  18. Coping with Computer Viruses: General Discussion and Review of Symantec Anti-Virus for the Macintosh.

    ERIC Educational Resources Information Center

    Primich, Tracy

    1992-01-01

    Discusses computer viruses that attack the Macintosh and describes Symantec AntiVirus for Macintosh (SAM), a commercial program designed to detect and eliminate viruses; sample screen displays are included. SAM is recommended for use in library settings as well as two public domain virus protection programs. (four references) (MES)

  19. Generation of virus like particles for epizootic hemorrhagic disease virus.

    PubMed

    Forzan, Mario; Maan, Sushila; Mazzei, Maurizio; Belaganahalli, Manjunatha N; Bonuccelli, Lucia; Calamari, Monica; Carrozza, Maria Luisa; Cappello, Valentina; Di Luca, Mariagrazia; Bandecchi, Patrizia; Mertens, Peter P C; Tolari, Francesco

    2016-08-01

    Epizootic hemorrhagic disease virus (EHDV) is a distinct species within the genus Orbivirus, within the family Reoviridae. The epizootic hemorrhagic disease virus genome comprises ten segments of linear, double stranded (ds) RNA, which are packaged within each virus particle. The EHDV virion has a three layered capsid-structure, generated by four major viral proteins: VP2 and VP5 (outer capsid layer); VP7 (intermediate, core-surface layer) and VP3 (innermost, sub-core layer). Although EHDV infects cattle sporadically, several outbreaks have recently occurred in this species in five Mediterranean countries, indicating a potential threat to the European cattle industry. EHDV is transmitted by biting midges of the genus Culicoides, which can travel long distances through wind-born movements (particularly over water), increasing the potential for viral spread in new areas/countries. Expression systems to generate self-assembled virus like particles (VLPs) by simultaneous expression of the major capsid-proteins, have been established for several viruses (including bluetongue virus). This study has developed expression systems for production of EHDV VLPs, for use as non-infectious antigens in both vaccinology and serology studies, avoiding the risk of genetic reassortment between vaccine and field strains and facilitating large scale antigen production. Genes encoding the four major-capsid proteins of a field strain of EHDV-6, were isolated and cloned into transfer vectors, to generate two recombinant baculoviruses. The expression of these viral genes was assessed in insect cells by monitoring the presence of specific viral mRNAs and by western blotting. Electron microscopy studies confirmed the formation and purification of assembled VLPs. PMID:27473984

  20. Feline Leukemia Virus Immunity Induced by Whole Inactivated Virus Vaccination

    PubMed Central

    Torres, Andrea N.; O’Halloran, Kevin P.; Larson, Laurie J.; Schultz, Ronald D.; Hoover, Edward A.

    2009-01-01

    A fraction of cats exposed to feline leukemia virus (FeLV) effectively contain virus and resist persistent antigenemia/viremia. Using real-time PCR (qPCR) to quantitate circulating viral DNA levels, previously we detected persistent FeLV DNA in blood cells of non-antigenemic cats considered to have resisted FeLV challenge. In addition, previously we used RNA qPCR to quantitate circulating viral RNA levels and determined that the vast majority of viral DNA is transcriptionally active, even in the absence of antigenemia. A single comparison of all USDA-licensed commercially available FeLV vaccines using these modern sensitive methods has not been reported. To determine whether FeLV vaccination would prevent nucleic acid persistence, we assayed circulating viral DNA, RNA, antigen, infectious virus, and virus neutralizing (VN) antibody in vaccinated and unvaccinated cats challenged with infectious FeLV. We identified challenged vaccinates with undetectable antigenemia and viremia concomitant with persistent FeLV DNA and/or RNA. Moreover, these studies demonstrated that two whole inactivated virus (WIV) adjuvanted FeLV vaccines (Fort Dodge Animal Health’s Fel-O-Vax Lv-K® and Schering-Plough Animal Health’s FEVAXYN FeLV®) provided effective protection against FeLV challenge. In nearly every recipient of these vaccines, neither viral DNA, RNA, antigen, nor infectious virus could be detected in blood after FeLV challenge. Interestingly, this effective viral containment occurred despite a weak to undetectable VN antibody response. The above findings reinforce the precept of FeLV infection as a unique model of effective retroviral immunity elicited by WIV vaccination, and as such holds valuable insights into retroviral immunoprevention and therapy. PMID:20004483

  1. Viruses and thyroiditis: an update

    PubMed Central

    Desailloud, Rachel; Hober, Didier

    2009-01-01

    Viral infections are frequently cited as a major environmental factor involved in subacute thyroiditis and autoimmune thyroid diseases This review examines the data related to the role of viruses in the development of thyroiditis. Our research has been focused on human data. We have reviewed virological data for each type of thyroiditis at different levels of evidence; epidemiological data, serological data or research on circulating viruses, direct evidence of thyroid tissue infection. Interpretation of epidemiological and serological data must be cautious as they don't prove that this pathogen is responsible for the disease. However, direct evidence of the presence of viruses or their components in the organ are available for retroviruses (HFV) and mumps in subacute thyroiditis, for retroviruses (HTLV-1, HFV, HIV and SV40) in Graves's disease and for HTLV-1, enterovirus, rubella, mumps virus, HSV, EBV and parvovirus in Hashimoto's thyroiditis. However, it remains to determine whether they are responsible for thyroid diseases or whether they are just innocent bystanders. Further studies are needed to clarify the relationship between viruses and thyroid diseases, in order to develop new strategies for prevention and/or treatment. PMID:19138419

  2. Droplet Microfluidics for Virus Discovery

    NASA Astrophysics Data System (ADS)

    Rotem, Assaf; Cockrell, Shelley; Guo, Mira; Pipas, James; Weitz, David

    2012-02-01

    The ability to detect, isolate, and characterize an infectious agent is important for diagnosing and curing infectious diseases. Detecting new viral diseases is a challenge because the number of virus particles is often low and/or localized to a small subset of cells. Even if a new virus is detected, it is difficult to isolate it from clinical or environmental samples where multiple viruses are present each with very different properties. Isolation is crucial for whole genome sequencing because reconstructing a genome from fragments of many different genomes is practically impossible. We present a Droplet Microfluidics platform that can detect, isolate and sequence single viral genomes from complex samples containing mixtures of many viruses. We use metagenomic information about the sample of mixed viruses to select a short genomic sequence whose genome we are interested in characterizing. We then encapsulate single virions from the same sample in picoliter volume droplets and screen for successful PCR amplification of the sequence of interest. The selected drops are pooled and their contents sequenced to reconstruct the genome of interest. This method provides a general tool for detecting, isolating and sequencing genetic elements in clinical and environmental samples.

  3. Designing herpes viruses as oncolytics

    PubMed Central

    Peters, Cole; Rabkin, Samuel D

    2015-01-01

    Oncolytic herpes simplex virus (oHSV) was one of the first genetically-engineered oncolytic viruses. Because HSV is a natural human pathogen that can cause serious disease, it is incumbent that it can be genetically-engineered or significantly attenuated for safety. Here, we present a detailed explanation of the functions of HSV-1 genes frequently mutated to endow oncolytic activity. These genes are nonessential for growth in tissue culture cells but are important for growth in postmitotic cells, interfering with intrinsic antiviral and innate immune responses or causing pathology, functions dispensable for replication in cancer cells. Understanding the function of these genes leads to informed creation of new oHSVs with better therapeutic efficacy. Virus infection and replication can also be directed to cancer cells through tumor-selective receptor binding and transcriptional- or post-transcriptional miRNA-targeting, respectively. In addition to the direct effects of oHSV on infected cancer cells and tumors, oHSV can be “armed” with transgenes that are: reporters, to track virus replication and spread; cytotoxic, to kill uninfected tumor cells; immune modulatory, to stimulate antitumor immunity; or tumor microenvironment altering, to enhance virus spread or to inhibit tumor growth. In addition to HSV-1, other alphaherpesviruses are also discussed for their oncolytic activity. PMID:26462293

  4. Control of viruses infecting grapevine.

    PubMed

    Maliogka, Varvara I; Martelli, Giovanni P; Fuchs, Marc; Katis, Nikolaos I

    2015-01-01

    Grapevine is a high value vegetatively propagated fruit crop that suffers from numerous viruses, including some that seriously affect the profitability of vineyards. Nowadays, 64 viruses belonging to different genera and families have been reported in grapevines and new virus species will likely be described in the future. Three viral diseases namely leafroll, rugose wood, and infectious degeneration are of major economic importance worldwide. The viruses associated with these diseases are transmitted by mealybugs, scale and soft scale insects, or dagger nematodes. Here, we review control measures of the major grapevine viral diseases. More specifically, emphasis is laid on (i) approaches for the production of clean stocks and propagative material through effective sanitation, robust diagnosis, as well as local and regional certification efforts, (ii) the management of vectors of viruses using cultural, biological, and chemical methods, and (iii) the production of resistant grapevines mainly through the application of genetic engineering. The benefits and limitations of the different control measures are discussed with regard to accomplishments and future research directions.

  5. Quantitative nanoscale electrostatics of viruses.

    PubMed

    Hernando-Pérez, M; Cartagena-Rivera, A X; Lošdorfer Božič, A; Carrillo, P J P; San Martín, C; Mateu, M G; Raman, A; Podgornik, R; de Pablo, P J

    2015-11-01

    Electrostatics is one of the fundamental driving forces of the interaction between biomolecules in solution. In particular, the recognition events between viruses and host cells are dominated by both specific and non-specific interactions and the electric charge of viral particles determines the electrostatic force component of the latter. Here we probe the charge of individual viruses in liquid milieu by measuring the electrostatic force between a viral particle and the Atomic Force Microscope tip. The force spectroscopy data of co-adsorbed ϕ29 bacteriophage proheads and mature virions, adenovirus and minute virus of mice capsids is utilized for obtaining the corresponding density of charge for each virus. The systematic differences of the density of charge between the viral particles are consistent with the theoretical predictions obtained from X-ray structural data. Our results show that the density of charge is a distinguishing characteristic of each virus, depending crucially on the nature of the viral capsid and the presence/absence of the genetic material. PMID:26228582

  6. RB virus: a strain of Friend virus that produces a 'Friend virus-like' disease in Fv-2rr mice.

    PubMed

    Geib, R W; Seaward, M B; Stevens, M L; Cho, C L; Majumdar, M

    1989-10-01

    RB virus is a newly derived strain of Friend virus that was adapted to produce a 'Friend-like' disease in mice that are genetically resistant to wild-type Friend virus. RB virus was produced by passing high titers of the wild-type Friend virus (Lilly-Steeves polycythemia-producing strain) through adult Fv-2rr mice. Titration of the defective spleen focus-forming virus indicated RB virus infected similar numbers of Fv-2ss or Fv-2rr target cells. Analysis of the spleens from mice infected with RB virus indicated that RB induced the early stage of Friend disease (erythroid proliferation) in both Fv-2rr and Fv-2ss mice. Fv-2ss mice infected with RB virus developed the classical Friend disease within 3 weeks. In contrast, the percentage of Fv-2rr mice developing the 'Friend-like' disease after infection with RB virus never exceeded 60%. The latency period of RBV in Fv-2rr mice was strain dependent. D2.R16 (Fv-2rr) developed the syndrome more rapidly than C57BL/6 (Fv-2rr). RB virus retained the capacity to transform erythroprogenitor cells from both Fv-2ss and Fv-2rr animals. Cells infected with RB virus consistently produced a modified SFFV envelope protein, gp48.

  7. Influenza Virus Infection of Marine Mammals.

    PubMed

    Fereidouni, Sasan; Munoz, Olga; Von Dobschuetz, Sophie; De Nardi, Marco

    2016-03-01

    Interspecies transmission may play a key role in the evolution and ecology of influenza A viruses. The importance of marine mammals as hosts or carriers of potential zoonotic pathogens such as highly pathogenic H5 and H7 influenza viruses is not well understood. The fact that influenza viruses are some of the few zoonotic pathogens known to have caused infection in marine mammals, evidence for direct transmission of influenza A virus H7N7 subtype from seals to man, transmission of pandemic H1N1 influenza viruses to seals and also limited evidence for long-term persistence of influenza B viruses in seal populations without significant genetic change, makes monitoring of influenza viruses in marine mammal populations worth being performed. In addition, such monitoring studies could be a great tool to better understand the ecology of influenza viruses in nature. PMID:25231137

  8. A Multicomponent Animal Virus Isolated from Mosquitoes.

    PubMed

    Ladner, Jason T; Wiley, Michael R; Beitzel, Brett; Auguste, Albert J; Dupuis, Alan P; Lindquist, Michael E; Sibley, Samuel D; Kota, Krishna P; Fetterer, David; Eastwood, Gillian; Kimmel, David; Prieto, Karla; Guzman, Hilda; Aliota, Matthew T; Reyes, Daniel; Brueggemann, Ernst E; St John, Lena; Hyeroba, David; Lauck, Michael; Friedrich, Thomas C; O'Connor, David H; Gestole, Marie C; Cazares, Lisa H; Popov, Vsevolod L; Castro-Llanos, Fanny; Kochel, Tadeusz J; Kenny, Tara; White, Bailey; Ward, Michael D; Loaiza, Jose R; Goldberg, Tony L; Weaver, Scott C; Kramer, Laura D; Tesh, Robert B; Palacios, Gustavo

    2016-09-14

    RNA viruses exhibit a variety of genome organization strategies, including multicomponent genomes in which each segment is packaged separately. Although multicomponent genomes are common among viruses infecting plants and fungi, their prevalence among those infecting animals remains unclear. We characterize a multicomponent RNA virus isolated from mosquitoes, designated Guaico Culex virus (GCXV). GCXV belongs to a diverse clade of segmented viruses (Jingmenvirus) related to the prototypically unsegmented Flaviviridae. The GCXV genome comprises five segments, each of which appears to be separately packaged. The smallest segment is not required for replication, and its presence is variable in natural infections. We also describe a variant of Jingmen tick virus, another Jingmenvirus, sequenced from a Ugandan red colobus monkey, thus expanding the host range of this segmented and likely multicomponent virus group. Collectively, this study provides evidence for the existence of multicomponent animal viruses and their potential relevance for animal and human health.

  9. A Multicomponent Animal Virus Isolated from Mosquitoes.

    PubMed

    Ladner, Jason T; Wiley, Michael R; Beitzel, Brett; Auguste, Albert J; Dupuis, Alan P; Lindquist, Michael E; Sibley, Samuel D; Kota, Krishna P; Fetterer, David; Eastwood, Gillian; Kimmel, David; Prieto, Karla; Guzman, Hilda; Aliota, Matthew T; Reyes, Daniel; Brueggemann, Ernst E; St John, Lena; Hyeroba, David; Lauck, Michael; Friedrich, Thomas C; O'Connor, David H; Gestole, Marie C; Cazares, Lisa H; Popov, Vsevolod L; Castro-Llanos, Fanny; Kochel, Tadeusz J; Kenny, Tara; White, Bailey; Ward, Michael D; Loaiza, Jose R; Goldberg, Tony L; Weaver, Scott C; Kramer, Laura D; Tesh, Robert B; Palacios, Gustavo

    2016-09-14

    RNA viruses exhibit a variety of genome organization strategies, including multicomponent genomes in which each segment is packaged separately. Although multicomponent genomes are common among viruses infecting plants and fungi, their prevalence among those infecting animals remains unclear. We characterize a multicomponent RNA virus isolated from mosquitoes, designated Guaico Culex virus (GCXV). GCXV belongs to a diverse clade of segmented viruses (Jingmenvirus) related to the prototypically unsegmented Flaviviridae. The GCXV genome comprises five segments, each of which appears to be separately packaged. The smallest segment is not required for replication, and its presence is variable in natural infections. We also describe a variant of Jingmen tick virus, another Jingmenvirus, sequenced from a Ugandan red colobus monkey, thus expanding the host range of this segmented and likely multicomponent virus group. Collectively, this study provides evidence for the existence of multicomponent animal viruses and their potential relevance for animal and human health. PMID:27569558

  10. Control of virus diseases of berry crops.

    PubMed

    Martin, Robert R; Tzanetakis, Ioannis E

    2015-01-01

    Virus control in berry crops starts with the development of plants free of targeted pathogens, usually viruses, viroids, phytoplasmas, and systemic bacteria, through a combination of testing and therapy. These then become the top-tier plants in certification programs and are the source from which all certified plants are produced, usually after multiple cycles of propagation. In certification schemes, efforts are made to produce plants free of the targeted pathogens to provide plants of high health status to berry growers. This is achieved using a systems approach to manage virus vectors. Once planted in fruit production fields, virus control shifts to disease control where efforts are focused on controlling viruses or virus complexes that result in disease. In fruiting fields, infection with a virus that does not cause disease is of little concern to growers. Virus control is based on the use of resistance and tolerance, vector management, and isolation.

  11. Virus Discovery Using Tick Cell Lines

    PubMed Central

    Bell-Sakyi, Lesley; Attoui, Houssam

    2016-01-01

    While ticks have been known to harbor and transmit pathogenic arboviruses for over 80 years, the application of high-throughput sequencing technologies has revealed that ticks also appear to harbor a diverse range of endogenous tick-only viruses belonging to many different families. Almost nothing is known about these viruses; indeed, it is unclear in most cases whether the identified viral sequences are derived from actual replication-competent viruses or from endogenous virus elements incorporated into the ticks’ genomes. Tick cell lines play an important role in virus discovery and isolation through the identification of novel viruses chronically infecting such cell lines and by acting as host cells to aid in determining whether or not an entire replication-competent, infective virus is present in a sample. Here, we review recent progress in tick-borne virus discovery and comment on the actual and potential applications for tick cell lines in this emerging research area. PMID:27679414

  12. Infectious enveloped RNA virus antigenic chimeras.

    PubMed

    London, S D; Schmaljohn, A L; Dalrymple, J M; Rice, C M

    1992-01-01

    Random insertion mutagenesis has been used to construct infectious Sindbis virus structural protein chimeras containing a neutralization epitope from a heterologous virus, Rift Valley fever virus. Insertion sites, permissive for recovery of chimeric viruses with growth properties similar to the parental virus, were found in the virion E2 glycoprotein and the secreted E3 glycoprotein. For the E2 chimeras, the epitope was expressed on the virion surface and stimulated a partially protective immune response to Rift Valley fever virus infection in vivo. Besides providing a possible approach for developing live attenuated vaccine viruses, insertion of peptide ligands into virion surface proteins may ultimately allow targeting of virus infection to specific cell types.

  13. Virus Discovery Using Tick Cell Lines

    PubMed Central

    Bell-Sakyi, Lesley; Attoui, Houssam

    2016-01-01

    While ticks have been known to harbor and transmit pathogenic arboviruses for over 80 years, the application of high-throughput sequencing technologies has revealed that ticks also appear to harbor a diverse range of endogenous tick-only viruses belonging to many different families. Almost nothing is known about these viruses; indeed, it is unclear in most cases whether the identified viral sequences are derived from actual replication-competent viruses or from endogenous virus elements incorporated into the ticks’ genomes. Tick cell lines play an important role in virus discovery and isolation through the identification of novel viruses chronically infecting such cell lines and by acting as host cells to aid in determining whether or not an entire replication-competent, infective virus is present in a sample. Here, we review recent progress in tick-borne virus discovery and comment on the actual and potential applications for tick cell lines in this emerging research area.

  14. Swine Influenza/Variant Influenza Viruses

    MedlinePlus

    ... Humans Key Facts about Human Infections with Variant Viruses Interim Guidance for Clinicians on Human Infections Background, Risk Assessment & Reporting Reported Infections with Variant Influenza Viruses in the United States since 2005 Prevention Treatment ...

  15. Avian Influenza A Virus Infections in Humans

    MedlinePlus

    ... Research Making a Candidate Vaccine Virus Related Links Influenza Types Seasonal Avian Swine Variant Pandemic Other Get ... Submit What's this? Submit Button Past Newsletters Avian Influenza A Virus Infections in Humans Language: English Españ ...

  16. A "virus" disease of chinook salmon

    USGS Publications Warehouse

    Ross, A.J.; Rucker, R.R.

    1960-01-01

    Epizootics among chinook salmon fingerlings at the Coleman National Fish Hatchery have occurred periodically since 1941. A virus or virus-like filterable agent has been demonstrated to be the causative agent of this disease.

  17. The Origins of the AIDS Virus.

    ERIC Educational Resources Information Center

    Essex, Max; Kanki, Phyllis J.

    1988-01-01

    States that the virus is not unique since it has been discovered in other primates as well as in man. Relates studies of viruses that indicate some have evolved disease-free coexistence with their animal hosts. (RT)

  18. FAQ: West Nile Virus and Dead Birds

    MedlinePlus

    ... Education Public Service Videos West Nile Virus & Dead Birds Recommend on Facebook Tweet Share Compartir On this ... dead bird sightings to local authorities. How do birds get infected with West Nile virus? West Nile ...

  19. A Literature Review of Zika Virus.

    PubMed

    Plourde, Anna R; Bloch, Evan M

    2016-07-01

    Zika virus is a mosquitoborne flavivirus that is the focus of an ongoing pandemic and public health emergency. Previously limited to sporadic cases in Africa and Asia, the emergence of Zika virus in Brazil in 2015 heralded rapid spread throughout the Americas. Although most Zika virus infections are characterized by subclinical or mild influenza-like illness, severe manifestations have been described, including Guillain-Barre syndrome in adults and microcephaly in babies born to infected mothers. Neither an effective treatment nor a vaccine is available for Zika virus; therefore, the public health response primarily focuses on preventing infection, particularly in pregnant women. Despite growing knowledge about this virus, questions remain regarding the virus's vectors and reservoirs, pathogenesis, genetic diversity, and potential synergistic effects of co-infection with other circulating viruses. These questions highlight the need for research to optimize surveillance, patient management, and public health intervention in the current Zika virus epidemic.

  20. A Literature Review of Zika Virus.

    PubMed

    Plourde, Anna R; Bloch, Evan M

    2016-07-01

    Zika virus is a mosquitoborne flavivirus that is the focus of an ongoing pandemic and public health emergency. Previously limited to sporadic cases in Africa and Asia, the emergence of Zika virus in Brazil in 2015 heralded rapid spread throughout the Americas. Although most Zika virus infections are characterized by subclinical or mild influenza-like illness, severe manifestations have been described, including Guillain-Barre syndrome in adults and microcephaly in babies born to infected mothers. Neither an effective treatment nor a vaccine is available for Zika virus; therefore, the public health response primarily focuses on preventing infection, particularly in pregnant women. Despite growing knowledge about this virus, questions remain regarding the virus's vectors and reservoirs, pathogenesis, genetic diversity, and potential synergistic effects of co-infection with other circulating viruses. These questions highlight the need for research to optimize surveillance, patient management, and public health intervention in the current Zika virus epidemic. PMID:27070380