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Sample records for swine fever virus

  1. African Swine Fever Virus, Siberia, Russia, 2017.

    Science.gov (United States)

    Kolbasov, Denis; Titov, Ilya; Tsybanov, Sodnom; Gogin, Andrey; Malogolovkin, Alexander

    2018-04-01

    African swine fever (ASF) is arguably the most dangerous and emerging swine disease worldwide. ASF is a serious problem for the swine industry. The first case of ASF in Russia was reported in 2007. We report an outbreak of ASF in Siberia, Russia, in 2017.

  2. Molecular characterization of African swine fever virus in apparently ...

    African Journals Online (AJOL)

    African swine fever (ASF) is a highly lethal and economically significant disease of domestic pigs in Uganda where outbreaks regularly occur. There is neither a vaccine nor treatment available for ASF control. Twenty two African swine fever virus (ASFV) genotypes (I - XXII) have been identified based on partial sequencing ...

  3. Close Relationship of Ruminant Pestiviruses and Classical Swine Fever Virus

    Science.gov (United States)

    Postel, Alexander; Schmeiser, Stefanie; Oguzoglu, Tuba Cigdem; Indenbirken, Daniela; Alawi, Malik; Fischer, Nicole; Grundhoff, Adam

    2015-01-01

    To determine why serum from small ruminants infected with ruminant pestiviruses reacted positively to classical swine fever virus (CSFV)–specific diagnostic tests, we analyzed 2 pestiviruses from Turkey. They differed genetically and antigenically from known Pestivirus species and were closely related to CSFV. Cross-reactions would interfere with classical swine fever diagnosis in pigs. PMID:25811683

  4. African Swine Fever Virus Biology and Vaccine Approaches.

    Science.gov (United States)

    Revilla, Yolanda; Pérez-Núñez, Daniel; Richt, Juergen A

    2018-01-01

    African swine fever (ASF) is an acute and often fatal disease affecting domestic pigs and wild boar, with severe economic consequences for affected countries. ASF is endemic in sub-Saharan Africa and the island of Sardinia, Italy. Since 2007, the virus emerged in the republic of Georgia, and since then spread throughout the Caucasus region and Russia. Outbreaks have also been reported in Belarus, Ukraine, Lithuania, Latvia, Estonia, Romania, Moldova, Czech Republic, and Poland, threatening neighboring West European countries. The causative agent, the African swine fever virus (ASFV), is a large, enveloped, double-stranded DNA virus that enters the cell by macropinocytosis and a clathrin-dependent mechanism. African Swine Fever Virus is able to interfere with various cellular signaling pathways resulting in immunomodulation, thus making the development of an efficacious vaccine very challenging. Inactivated preparations of African Swine Fever Virus do not confer protection, and the role of antibodies in protection remains unclear. The use of live-attenuated vaccines, although rendering suitable levels of protection, presents difficulties due to safety and side effects in the vaccinated animals. Several African Swine Fever Virus proteins have been reported to induce neutralizing antibodies in immunized pigs, and vaccination strategies based on DNA vaccines and recombinant proteins have also been explored, however, without being very successful. The complexity of the virus particle and the ability of the virus to modulate host immune responses are most likely the reason for this failure. Furthermore, no permanent cell lines able to sustain productive virus infection by both virulent and naturally attenuated African Swine Fever Virus strains exist so far, thus impairing basic research and the commercial production of attenuated vaccine candidates. © 2018 Elsevier Inc. All rights reserved.

  5. Functional analysis of replication determinantsin classical swine fever virus

    DEFF Research Database (Denmark)

    Hadsbjerg, Johanne

    and animal pathogens should facilitate finding new approaches for efficient disease control. The principal aim of this thesis is to characterise determinants involved in the replication of classical swine fever virus (CSFV). Classical swine fever is a highly contagious virus disease of domestic pigs and wild...... in cell culture. Knowledge of these sequence variations and putative long-range interactions will provide valuable insights into mechanisms underlying virustranslation and replication. In manuscript 3, a selection marker has been inserted into a CSFV-based replicon making it suitable for screening...

  6. Modulation of Translation Initiation Efficiency in Classical Swine Fever Virus

    DEFF Research Database (Denmark)

    Friis, Martin Barfred; Rasmussen, Thomas Bruun; Belsham, Graham

    2012-01-01

    Modulation of translation initiation efficiency on classical swine fever virus (CSFV) RNA can be achieved by targeted mutations within the internal ribosome entry site (IRES). In this study, cDNAs corresponding to the wild type (wt) or mutant forms of the IRES of CSFV strain Paderborn were...... in vitro and electroporated into porcine PK15 cells. Rescued mutant viruses were obtained from RNAs that contained mutations within domain IIIf which retained more than 75% of wt translation efficiency. Sequencing of cDNA generated from these rescued viruses verified the maintenance of the introduced...... changes within the IRES. The growth characteristics of each rescued mutant virus were compared to that of the wt virus. It was shown that viable mutant viruses with reduced translation initiation efficiency can be designed and generated and that viruses containing mutations within domain IIIf of the IRES...

  7. Proteomic analysis of swine serum following highly virulent classical swine fever virus infection

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    Guo Huan-cheng

    2011-03-01

    Full Text Available Abstract Background Classical swine fever virus (CSFV belongs to the genus Pestivirus within the family Flaviviridae. Virulent strains of classical swine fever virus (CSFV cause severe disease in pigs characterized by immunosuppression, thrombocytopenia and disseminated intravascular coagulation, which causes significant economic losses to the pig industry worldwide. Methods To reveal proteomic changes in swine serum during the acute stage of lethal CSFV infection, 5 of 10 pigs were inoculated with the virulent CSFV Shimen strain, the remainder serving as uninfected controls. A serum sample was taken at 3 days post-infection from each swine, at a stage when there were no clinical symptoms other than increased rectal temperatures (≥40°C. The samples were treated to remove serum albumin and immunoglobulin (IgG, and then subjected to two-dimension differential gel electrophoresis. Results Quantitative intensity analysis revealed 17 protein spots showing at least 1.5-fold quantitative alteration in expression. Ten spots were successfully identified by MALDI-TOF MS or LTQ MS. Expression of 4 proteins was increased and 6 decreased in CSFV-infected pigs. Functions of these proteins included blood coagulation, anti-inflammatory activity and angiogenesis. Conclusion These proteins with altered expression may have important implications in the pathogenesis of classical swine fever and provide a clue for identification of biomarkers for classical swine fever early diagnosis.

  8. Estimation of the transmission dynamics of African swine fever virus within a swine house

    DEFF Research Database (Denmark)

    Nielsen, J. P.; Larsen, T. S.; Hisham Beshara Halasa, Tariq

    2017-01-01

    The spread of African swine fever virus (ASFV) threatens to reach further parts of Europe. In countries with a large swine production, an outbreak of ASF may result in devastating economic consequences for the swine industry. Simulation models can assist decision makers setting up contingency plans......·00 (95% CI 0-1). Furthermore, we simulated the spread of ASFV within a pig house using a modified SEIR-model to establish the time from infection of one animal until ASFV is detected in the herd. Based on a chosen detection limit of 2·55% equivalent to 10 dead pigs out of 360, the disease would...

  9. No evidence of African swine fever virus replication in hard ticks

    NARCIS (Netherlands)

    Carvalho Ferreira, de H.C.; Zúquete, S.T.; Wijnveld, M.; Weesendorp, E.; Jongejan, F.; Stegeman, J.A.; Loeffen, W.L.A.

    2014-01-01

    African swine fever (ASF) is caused by African swine fever virus (ASFV), a tick-borne DNA virus. Soft ticks of the genus Ornithodoros are the only biological vectors of ASFV recognized so far. Although other hard ticks have been tested for vector competence, two commonly found tick species in

  10. No evidence of African swine fever virus replication in hard ticks

    NARCIS (Netherlands)

    de Carvalho Ferreira, Helena C; Tudela Zúquete, Sara; Wijnveld, Michiel; Weesendorp, Eefke; Jongejan, Frans; Stegeman, Arjan; Loeffen, Willie L A

    African swine fever (ASF) is caused by African swine fever virus (ASFV), a tick-borne DNA virus. Soft ticks of the genus Ornithodoros are the only biological vectors of ASFV recognized so far. Although other hard ticks have been tested for vector competence, two commonly found tick species in

  11. Modulation of Translation Initiation Efficiency in Classical Swine Fever Virus

    DEFF Research Database (Denmark)

    Friis, Martin Barfred; Rasmussen, Thomas Bruun; Belsham, Graham J.

    Modulation of translation initiation efficiency on classical swine fever virus (CSFV) RNA can be achieved by targeted mutations within the internal ribosome entry site (IRES). In this study, the nucleotides 47 to 427, including the IRES region of the wt CSFV strain Paderborn, were amplified...... and inserted, under T7 promoter control, into mono- and dicistronic plasmids containing the reporter genes rLuc and fLuc. Mutant fragments of the IRES sequence were generated by overlap PCR and inserted into the reporter plasmids. To evaluate IRES functionality, translation of the rLUC was placed under...... viruses were obtained after one cell culture passage from constructs with more than 75 % translation efficiency compared to the wildtype IRES. cDNA was generated from these clones and sequenced to verify the maintenance of the changes in the IRES. These results show that full-length viable mutant viruses...

  12. Immunofluorescence Plaque Assay for African Swine Fever Virus

    Science.gov (United States)

    Tessler, J.; Hess, W. R.; Pan, I. C.; Trautman, R.

    1974-01-01

    Suitably diluted cell culture adapted African swine fever virus preparations were inoculated on VERO cell monolayers and grown on coverslips. Gum tragacanth was used as an overlay. After three days incubation at 37°C the infected cultures were fixed with acetone and stained with fluorescent antibody conjugate. Fluorescing plaques consisted of 20-30 infected cells. Three statistical criteria for a quantitatively reliable assay were met: the Poisson distribution for plaque counts, linearity of the relationship between the concentration of virus and the plaque count and reproducibility of replicate titrations. The method is suitable for counts up to at least 70 plaques per 5 cm2 coverslip and computed titers are reproducible within 0.16 log units with a total of 300 plaques enumerated. PMID:4279763

  13. Prevalence of African swine fever virus and classical swine fever virus antibodies in pigs in Benue State, Nigeria.

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    Asambe, A; Sackey, A K B; Tekdek, L B

    2018-03-01

    This study investigated the prevalence of African swine fever virus (ASFV) and classical swine fever virus (CSFV) antibodies in pigs in Benue State, Nigeria. Serum samples were collected from a total of 460 pigs, including 416 from 74 piggeries and 44 from Makurdi slaughter slab. The samples were analysed using indirect enzyme-linked immunosorbent assay (ELISA) test kit to detect the presence of ASFV antibodies, while competitive ELISA test kit was used to detect antibodies to CSFV. Our findings showed a total ASF prevalence of 13 (2.8%), while prevalences of 7 (1.7%) and 6 (13.6%) were observed in piggeries and in Makurdi slaughter slab, respectively. However, no CSFV antibody sera were detected in this study. Relatively higher ASFV antibody-positive pigs were detected in the slaughter slab than in piggeries. The difference in prevalence of ASF between the two locations was significantly associated (p = 0.017). These findings suggest the presence of ASFV antibody-positive pig in Benue State, Nigeria. Continuous surveillance and monitoring of these diseases among pigs in Nigeria to prevent any fulminating outbreak are recommended.

  14. Virulence determinants within the E2 glycoprotein of Classical Swine Fever Virus

    DEFF Research Database (Denmark)

    Johnston, Camille Melissa; Fahnøe, Ulrik; Lohse, Louise

    Classical Swine Fever is a highly contagious disease of pigs caused by Classical Swine Fever Virus (CSFV), a member of the pestivirus genus within the family Flaviviridae. The E2 glycoprotein of CSFV has been shown to be an important factor for the virulence of the virus. In a recent study, we have......Kos (with the SL motif). The results indicate that the E2 residues 763-64 play an important role in CSFV virulence....

  15. CRISPR-Cas9, a tool to efficiently increase the development of recombinant African swine fever viruses

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    African swine fever is a contagious and often lethal disease for domestic pigs with a significant economic impact on the swine industry. The etiological agent, African swine fever virus (ASFV), is a highly structurally complex double stranded DNA virus. No effective vaccines or antiviral treatment ...

  16. DETECTION OF CLASSICAL SWINE FEVER VIRUS BY RT-PCR IN WEST BENGAL, INDIA

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    Sumit Chowdhury

    2016-12-01

    Full Text Available Classical swine fever is a deadly disease of swine, caused by a RNA virus. The present study has identified presence of the classical swine fever virus (CSFV in pigs of West Bengal by one step reverse transcriptase PCR (RT-PCR performed using 5’ NTR specific primers. Internal organs from clinically affected pigs were examined from three districts of West Bengal. RT-PCT has identified presence of CSFV in all the tissues examined confirming presence of CSFV in different parts of the state.

  17. Accelerating vaccine development for African swine fever virus ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Photo: IDRC / Bartay The challenge African swine fever (ASF) is a highly infectious hemorrhagic viral disease that wipes out entire herds of infected pigs. ASF is widespread in at least half of sub-Saharan Africa, and threatens food security due to devastating economic losses.

  18. Deletion of the thymidine kinase gene induces complete attenuation of the Georgia isolate of African swine fever virus

    Science.gov (United States)

    African swine fever virus (ASFV) is the etiological agent of a contagious and often lethal viral disease of domestic pigs. There are no vaccines to control Africa swine fever (ASF). Experimental vaccines have been developed using genetically modified live attenuated ASFVs obtained by specifically de...

  19. Uncovering of Classical Swine Fever Virus adaptive response to vaccination by Next Generation Sequencing

    DEFF Research Database (Denmark)

    Fahnøe, Ulrik; Orton, Richard; Höper, Dirk

    Next Generation Sequencing (NGS) has rapidly become the preferred technology in nucleotide sequencing, and can be applied to unravel molecular adaptation of RNA viruses such as Classical Swine Fever Virus (CSFV). However, the detection of low frequency variants within viral populations by NGS...... is affected by errors introduced during sample preparation and sequencing, and so far no definitive solution to this problem has been presented....

  20. Alteration of a second putative fusion peptide of structural glycoprotein E2 of Classical Swine Fever Virus alters virus replication and virulence in swine

    Science.gov (United States)

    E2, the major envelope glycoprotein of Classical Swine Fever Virus (CSFV), is involved in several critical virus functions including cell attachment, host range susceptibility, and virulence in natural hosts. Functional structural analysis of E2 based on Wimley-White interfacial hydrophobicity dis...

  1. CRISPR-Cas9, a tool to efficiently increase the development of recombinant African swine fever viruses.

    Science.gov (United States)

    Borca, Manuel V; Holinka, Lauren G; Berggren, Keith A; Gladue, Douglas P

    2018-02-16

    African swine fever virus (ASFV) causes a highly contagious disease called African swine fever. This disease is often lethal for domestic pigs, causing extensive losses for the swine industry. ASFV is a large and complex double stranded DNA virus. Currently there is no commercially available treatment or vaccine to prevent this devastating disease. Development of recombinant ASFV for producing live-attenuated vaccines or studying the involvement of specific genes in virus virulence has relied on the relatively rare event of homologous recombination in primary swine macrophages, causing difficulty to purify the recombinant virus from the wild-type parental ASFV. Here we present the use of the CRISPR-Cas9 gene editing system as a more robust and efficient system to produce recombinant ASFVs. Using CRISPR-Cas9 a recombinant virus was efficiently developed by deleting the non-essential gene 8-DR from the genome of the highly virulent field strain Georgia07 using swine macrophages as cell substrate.

  2. Virus survival in slurry: Analysis of the stability of foot-and-mouth disease, classical swine fever, bovine viral diarrhoea and swine influenza viruses

    DEFF Research Database (Denmark)

    Bøtner, Anette; Belsham, Graham

    2012-01-01

    of an outbreak of disease before it has been recognized. The survival of foot-and-mouth disease virus, classical swine fever virus, bovine viral diarrhoea virus and swine influenza virus, which belong to three different RNA virus families plus porcine parvovirus (a DNA virus) was examined under controlled...... conditions. For each RNA virus, the virus survival in farm slurry under anaerobic conditions was short (generally ≤1h) when heated (to 55°C) but each of these viruses could retain infectivity at cool temperatures (5°C) for many weeks. The porcine parvovirus survived considerably longer than each of the RNA...... viruses under all conditions tested. The implications for disease spread are discussed....

  3. Roles of African swine fever virus structural proteins in viral infection

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    Jia Ning

    2017-06-01

    Full Text Available African swine fever virus (ASFV is a large, double-stranded DNA virus and the sole member of the Asfarviridae family. ASFV infects domestic pigs, wild boars, warthogs, and bush pigs, as well as soft ticks (Ornithodoros erraticus, which likely act as a vector. The major target is swine monocyte-macrophage cells. The virus can cause high fever, haemorrhagic lesions, cyanosis, anorexia, and even fatalities in domestic pigs. Currently, there is no vaccine and effective disease control strategies against its spread are culling infected pigs and maintaining high biosecurity standards. African swine fever (ASF spread to Europe from Africa in the middle of the 20th century, and later also to South America and the Caribbean. Since then, ASF has spread more widely and thus is still a great challenge for swine breeding. The genome of ASFV ranges in length from about 170 to 193 kbp depending on the isolate and contains between 150 and 167 open reading frames (ORFs. The ASFV genome encodes 150 to 200 proteins, around 50 of them structural. The roles of virus structural proteins in viral infection have been described. These proteins, such as pp220, pp62, p72, p54, p30, and CD2v, serve as the major component of virus particles and have roles in attachment, entry, and replication. All studies on ASFV proteins lay a good foundation upon which to clarify the infection mechanism and develop vaccines and diagnosis methods. In this paper, the roles of ASFV structural proteins in viral infection are reviewed.

  4. Complex Virus-Host Interactions Involved in the Regulation of Classical Swine Fever Virus Replication: A Minireview.

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    Li, Su; Wang, Jinghan; Yang, Qian; Naveed Anwar, Muhammad; Yu, Shaoxiong; Qiu, Hua-Ji

    2017-07-05

    Classical swine fever (CSF), caused by classical swine fever virus (CSFV), is one of the most devastating epizootic diseases of pigs in many countries. Viruses are small intracellular parasites and thus rely on the cellular factors for replication. Fundamental aspects of CSFV-host interactions have been well described, such as factors contributing to viral attachment, modulation of genomic replication and translation, antagonism of innate immunity, and inhibition of cell apoptosis. However, those host factors that participate in the viral entry, assembly, and release largely remain to be elucidated. In this review, we summarize recent progress in the virus-host interactions involved in the life cycle of CSFV and analyze the potential mechanisms of viral entry, assembly, and release. We conclude with future perspectives and highlight areas that require further understanding.

  5. Genotyping of African swine fever virus (ASFV) isolates associated ...

    African Journals Online (AJOL)

    Four of these viruses were isolated directly from serum samples. All the viruses were classified within the domesticpig cycle-associated p72 and p54 genotype IX which also includes viruses responsible for ASF outbreaks in Kenya in 2006 and 2007 and Uganda in 2003. To define virus relationships at higher resolution, ...

  6. Simultaneous deletion of the 9GL and UK genes from the African swine fever virus Georgia 2007 isolate results in virus attenuation and may be a potential virus vaccine strain

    Science.gov (United States)

    African Swine Fever Virus (ASFV) is the etiological agent of a contagious and often lethal viral disease of domestic pigs that has significant economic consequences for the swine industry. The control of African Swine Fever (ASF) has been hampered by the unavailability of vaccines. Successful experi...

  7. Comparison of two Next Generation sequencing platforms for full genome sequencing of Classical Swine Fever Virus

    DEFF Research Database (Denmark)

    Fahnøe, Ulrik; Pedersen, Anders Gorm; Höper, Dirk

    2013-01-01

    to the consensus sequence. Additionally, we got an average sequence depth for the genome of 4000 for the Iontorrent PGM and 400 for the FLX platform making the mapping suitable for single nucleotide variant (SNV) detection. The analysis revealed a single non-silent SNV A10665G leading to the amino acid change D......Next Generation Sequencing (NGS) is becoming more adopted into viral research and will be the preferred technology in the years to come. We have recently sequenced several strains of Classical Swine Fever Virus (CSFV) by NGS on both Genome Sequencer FLX (GS FLX) and Iontorrent PGM platforms...

  8. Complete Genomes of Classical Swine Fever Virus Cloned into Bacterial Artificial Chromosomes

    DEFF Research Database (Denmark)

    Rasmussen, Thomas Bruun; Reimann, I.; Uttenthal, Åse

    Complete genome amplification of viral RNA provides a new tool for the generation of modified pestiviruses. We have used our full-genome amplification strategy for generation of amplicons representing complete genomes of classical swine fever virus. The amplicons were cloned directly into a stabl...... single-copy bacterial artificial chromosome (BAC) generating full-length pestivirus DNAs from which infectious RNA transcripts could be also derived. Our strategy allows construction of stable infectious BAC DNAs from a single full-length PCR product....

  9. Reconstructing the highly virulent Classical Swine Fever Virus strain Koslov

    DEFF Research Database (Denmark)

    Fahnøe, Ulrik; Pedersen, Anders Gorm; Nielsen, Jens

    -prone nature of the RNA-dependent RNA polymerase resulting in the majority of circulating forms being non-functional. However, since any infectious virus particle should necessarily be the offspring of a functional virus, we hypothesized that it should be possible to synthesize a highly virulent form...

  10. Approaches and Perspectives for Development of African Swine Fever Virus Vaccines

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    Marisa Arias

    2017-10-01

    Full Text Available African swine fever (ASF is a complex disease of swine, caused by a large DNA virus belonging to the family Asfarviridae. The disease shows variable clinical signs, with high case fatality rates, up to 100%, in the acute forms. ASF is currently present in Africa and Europe where it circulates in different scenarios causing a high socio-economic impact. In most affected regions, control has not been effective in part due to lack of a vaccine. The availability of an effective and safe ASFV vaccines would support and enforce control–eradication strategies. Therefore, work leading to the rational development of protective ASF vaccines is a high priority. Several factors have hindered vaccine development, including the complexity of the ASF virus particle and the large number of proteins encoded by its genome. Many of these virus proteins inhibit the host’s immune system thus facilitating virus replication and persistence. We review previous work aimed at understanding ASFV–host interactions, including mechanisms of protective immunity, and approaches for vaccine development. These include live attenuated vaccines, and “subunit” vaccines, based on DNA, proteins, or virus vectors. In the shorter to medium term, live attenuated vaccines are the most promising and best positioned candidates. Gaps and future research directions are evaluated.

  11. Serum neutralization as a differential serological test for classical swine fever virus and other pestivirus infections

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    Paredes J.C.M.

    1999-01-01

    Full Text Available Serum neutralization tests (SN were performed against classical swine fever virus (CSFV, bovine viral diarrhea virus (BVDV and border disease virus (BDV on samples of swine serum collected for screening of antibodies to CSFV, in order to determine the SN value as a differential serological test. Ninety-nine sera out of a sample of 16,664 were positive for antibodies to pestiviruses in an ELISA test which did not distinguish antibodies to different pestiviruses. When submitted to SN, 81 sera were positive for CSFV antibodies only. In 17 sera, crossreactive antibodies to either CSFV, BVDV or BDV were detected. In most of these sera (13 out of 17 the differences between SN titres against the three viruses were not sufficient to estimate which was the most likely antibody-inducing virus. It was concluded that, for the SN to be useful in such differentiation, it is essential to examine a sample which must include a representative number of sera from the same farm where suspect animals were detected. When isolated serum samples are examined, such as those obtained with the sampling strategy adopted here, the SN may give rise to inconclusive results.

  12. Identification of a new genotype of African swine fever Virus in domestic pigs from Ethiopia

    International Nuclear Information System (INIS)

    Achenbach, J.E.; Gallardo, C.; Nieto-Pelegrín, E.; Rivera-Arroyo, B.; Degefa-Negi, T.; Arias, M.; Jenberie, S.; Mulisa, D.D.; Gizaw, D.; Gelaye, E.; Chibssa, T.R.; Belaye, A.; Loitsch, A.; Forsa, M.; Yami, M.; Diallo, A.; Soler, A.; Lamien, C.E.

    2016-01-01

    Full text: African swine fever (ASF) is an important emerging transboundary animal disease (TAD), which currently has an impact on many countries in Africa, Eastern Europe, the Caucasus and the Russian Federation. The current situation in Europe shows the ability of the virus to rapidly spread, which stands to threaten the global swine industry. At present, there is no viable vaccine to minimize spread of the disease and stamping out is the main source of control. In February 2011, Ethiopia had reported its first suspected outbreaks of ASF. Genomic analyses of the collected ASF virus (ASFV) strains were undertaken using 23 tissue samples collected from domestic swine in Ethiopia from 2011 to 2014. The analysis of Ethiopian ASFVs partial p72 gene sequence showed the identification of a new genotype, genotype XXIII that shares a common ancestor with genotypes IX and X, which comprise isolates circulating in Eastern African countries and the Republic of Congo. Analysis of the p54 gene also followed the p72 pattern and the deduced amino acid sequence of the central variable region (CVR) of the B602L gene showed novel tetramer repeats not previously characterized. (author)

  13. Restoration of glycoprotein Erns dimerization via pseudoreversion partially restores virulence of classical swine fever virus.

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    Tucakov, Anna Katharina; Yavuz, Sabine; Schürmann, Eva-Maria; Mischler, Manjula; Klingebeil, Anne; Meyers, Gregor

    2018-01-01

    The classical swine fever virus (CSFV) represents one of the most important pathogens of swine. The CSFV glycoprotein E rns is an essential structural protein and an important virulence factor. The latter is dependent on the RNase activity of this envelope protein and, most likely, its secretion from the infected cell. A further important feature with regard to its function as a virulence factor is the formation of disulfide-linked E rns homodimers that are found in virus-infected cells and virions. Mutant CSFV lacking cysteine (Cys) 171, the residue responsible for intermolecular disulfide bond formation, were found to be attenuated in pigs (Tews BA, Schürmann EM, Meyers G. J Virol 2009;83:4823-4834). In the course of an animal experiment with such a dimerization-negative CSFV mutant, viruses were reisolated from pigs that contained a mutation of serine (Ser) 209 to Cys. This mutation restored the ability to form disulphide-linked E rns homodimers. In transient expression studies E rns mutants carrying the S209C change were found to form homodimers with about wt efficiency. Also the secretion level of the mutated proteins was equivalent to that of wt E rns . Virus mutants containing the Cys171Ser/Ser209Cys configuration exhibited wt growth rates and increased virulence when compared with the Cys171Ser mutant. These results provide further support for the connection between CSFV virulence and E rns dimerization.

  14. Induction of Robust Immune Responses in Swine by Using a Cocktail of Adenovirus-Vectored African Swine Fever Virus Antigens.

    Science.gov (United States)

    Lokhandwala, Shehnaz; Waghela, Suryakant D; Bray, Jocelyn; Martin, Cameron L; Sangewar, Neha; Charendoff, Chloe; Shetti, Rashmi; Ashley, Clay; Chen, Chang-Hsin; Berghman, Luc R; Mwangi, Duncan; Dominowski, Paul J; Foss, Dennis L; Rai, Sharath; Vora, Shaunak; Gabbert, Lindsay; Burrage, Thomas G; Brake, David; Neilan, John; Mwangi, Waithaka

    2016-11-01

    The African swine fever virus (ASFV) causes a fatal hemorrhagic disease in domestic swine, and at present no treatment or vaccine is available. Natural and gene-deleted, live attenuated strains protect against closely related virulent strains; however, they are yet to be deployed and evaluated in the field to rule out chronic persistence and a potential for reversion to virulence. Previous studies suggest that antibodies play a role in protection, but induction of cytotoxic T lymphocytes (CTLs) could be the key to complete protection. Hence, generation of an efficacious subunit vaccine depends on identification of CTL targets along with a suitable delivery method that will elicit effector CTLs capable of eliminating ASFV-infected host cells and confer long-term protection. To this end, we evaluated the safety and immunogenicity of an adenovirus-vectored ASFV (Ad-ASFV) multiantigen cocktail formulated in two different adjuvants and at two immunizing doses in swine. Immunization with the cocktail rapidly induced unprecedented ASFV antigen-specific antibody and cellular immune responses against all of the antigens. The robust antibody responses underwent rapid isotype switching within 1 week postpriming, steadily increased over a 2-month period, and underwent rapid recall upon boost. Importantly, the primed antibodies strongly recognized the parental ASFV (Georgia 2007/1) by indirect fluorescence antibody (IFA) assay and Western blotting. Significant antigen-specific gamma interferon-positive (IFN-γ + ) responses were detected postpriming and postboosting. Furthermore, this study is the first to demonstrate induction of ASFV antigen-specific CTL responses in commercial swine using Ad-ASFV multiantigens. The relevance of the induced immune responses in regard to protection needs to be evaluated in a challenge study. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  15. Association of the Host Immune Response with Protection Using a Live Attenuated African Swine Fever Virus Model.

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    Carlson, Jolene; O'Donnell, Vivian; Alfano, Marialexia; Velazquez Salinas, Lauro; Holinka, Lauren G; Krug, Peter W; Gladue, Douglas P; Higgs, Stephen; Borca, Manuel V

    2016-10-22

    African swine fever (ASF) is a lethal hemorrhagic disease of swine caused by a double-stranded DNA virus, ASF virus (ASFV). There is no vaccine to prevent the disease and current control measures are limited to culling and restricting animal movement. Swine infected with attenuated strains are protected against challenge with a homologous virulent virus, but there is limited knowledge of the host immune mechanisms generating that protection. Swine infected with Pretoriuskop/96/4 (Pret4) virus develop a fatal severe disease, while a derivative strain lacking virulence-associated gene 9GL (Pret4Δ9GL virus) is completely attenuated. Swine infected with Pret4Δ9GL virus and challenged with the virulent parental virus at 7, 10, 14, 21, and 28 days post infection (dpi) showed a progressive acquisition of protection (from 40% at 7 dpi to 80% at 21 and 28 dpi). This animal model was used to associate the presence of host immune response (ASFV-specific antibody and interferon (IFN)-γ responses, or specific cytokine profiles) and protection against challenge. With the exception of ASFV-specific antibodies in survivors challenged at 21 and 28 dpi, no association between the parameters assessed and protection could be established. These results, encompassing data from 65 immunized swine, underscore the complexity of the system under study, suggesting that protection relies on the concurrence of different host immune mechanisms.

  16. Association of the Host Immune Response with Protection Using a Live Attenuated African Swine Fever Virus Model

    Directory of Open Access Journals (Sweden)

    Jolene Carlson

    2016-10-01

    Full Text Available African swine fever (ASF is a lethal hemorrhagic disease of swine caused by a double-stranded DNA virus, ASF virus (ASFV. There is no vaccine to prevent the disease and current control measures are limited to culling and restricting animal movement. Swine infected with attenuated strains are protected against challenge with a homologous virulent virus, but there is limited knowledge of the host immune mechanisms generating that protection. Swine infected with Pretoriuskop/96/4 (Pret4 virus develop a fatal severe disease, while a derivative strain lacking virulence-associated gene 9GL (Pret4Δ9GL virus is completely attenuated. Swine infected with Pret4Δ9GL virus and challenged with the virulent parental virus at 7, 10, 14, 21, and 28 days post infection (dpi showed a progressive acquisition of protection (from 40% at 7 dpi to 80% at 21 and 28 dpi. This animal model was used to associate the presence of host immune response (ASFV-specific antibody and interferon (IFN-γ responses, or specific cytokine profiles and protection against challenge. With the exception of ASFV-specific antibodies in survivors challenged at 21 and 28 dpi, no association between the parameters assessed and protection could be established. These results, encompassing data from 65 immunized swine, underscore the complexity of the system under study, suggesting that protection relies on the concurrence of different host immune mechanisms.

  17. The risk of the introduction of classical swine fever virus at regional level in the European Union: a conceptual framework

    NARCIS (Netherlands)

    Vos, de C.J.; Saatkamp, H.W.; Huirne, R.B.M.; Dijkhuizen, A.A.

    2003-01-01

    Recent classical swine fever (CSF) epidemics in the European Union (EU) have clearly shown that preventing the introduction of CSF virus (CSFV) deserves high priority. Insight into all the factors contributing to the risk of CSFV introduction is a prerequisite for deciding which preventive actions

  18. Propagation of classical swine fever virus in vitro circumventing heparan sulfate-adaptation.

    Science.gov (United States)

    Eymann-Häni, Rita; Leifer, Immanuel; McCullough, Kenneth C; Summerfield, Artur; Ruggli, Nicolas

    2011-09-01

    Amplification of natural virus isolates in permanent cell lines can result in adaptation, in particular enhanced binding to heparan sulfate (HS)-containing glycosaminoglycans present on most vertebrate cells. This has been reported for several viruses, including the pestivirus classical swine fever virus (CSFV), the causative agent of a highly contagious hemorrhagic disease in pigs. Propagation of CSFV in cell culture is essential in virus diagnostics and research. Adaptation of CSFV to HS-binding has been related to amino acid changes in the viral E(rns) glycoprotein, resulting in viruses with altered replication characteristics in vitro and in vivo. Consequently, a compound blocking the HS-containing structures on cell surfaces was employed to monitor conversion from HS-independency to HS-dependency. It was shown that the porcine PEDSV.15 cell line permitted propagation of CSFV within a limited number of passages without adaptation to HS-binding. The selection of HS-dependent CSFV mutants was also prevented by propagation of the virus in the presence of DSTP 27. The importance of these findings can be seen from the altered ratio of cell-associated to secreted virus upon acquisition of enhanced HS-binding affinity, a phenotype proposed previously to be related to virulence in the natural host. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Sequence adaptations during growth of rescued classical swine fever viruses in cell culture and within infected pigs

    DEFF Research Database (Denmark)

    Hadsbjerg, Johanne; Friis, Martin Barfred; Fahnøe, Ulrik

    2016-01-01

    RNA could be detected. However, the animals inoculated with these mutant viruses seroconverted against CSFV. Thus, these mutant viruses were highly attenuated in vivo. All 4 rescued viruses were also passaged up to 20 times in cell culture. Using full genome sequencing, the same two adaptations within......Classical swine fever virus (CSFV) causes an economically important disease of swine. Four different viruses were rescued from full-length cloned cDNAs derived from the Paderborn strain of CSFV. Three of these viruses had been modified by mutagenesis (with 7 or 8 nt changes) within stem 2...... each of four independent virus populations were observed that restored the coding sequence to that of the parental field strain. These adaptations occurred with different kinetics. The combination of reverse genetics and in depth, full genome sequencing provides a powerful approach to analyse virus...

  20. Analysis of classical swine fever virus RNA replication determinants using replicons

    DEFF Research Database (Denmark)

    Risager, Peter Christian; Fahnøe, Ulrik; Gullberg, Maria

    2013-01-01

    Self-replicating RNAs (replicons), with or without reporter gene sequences, derived from the genome of the Paderborn strain of classical swine fever virus (CSFV) have been produced. The full-length viral cDNA, propagated within a bacterial artificial chromosome (BAC), was modified by targeted...... recombination within E. coli. RNA transcripts were produced in vitro and introduced into cells by electroporation. The translation and replication of the replicon RNAs could be followed by the accumulation of luciferase (from Renilla reniformis or Gaussia princeps) protein expression (where appropriate......), as well as by detection of the CSFV NS3 protein production within the cells. Inclusion of the viral E2 coding region within the replicon was advantageous for the replication efficiency. Production of chimeric RNAs, substituting the NS2 and NS3 coding regions (as a unit) from the Paderborn strain...

  1. Disinfection of foot-and-mouth disease and African swine fever viruses with citric acid and sodium hypochlorite on birch wood carriers

    Science.gov (United States)

    Transboundary animal disease viruses such as foot-and-mouth disease virus (FMDV) and African swine fever virus (ASFV) are highly contagious and cause severe morbidity and mortality in livestock. Proper disinfection during an outbreak can help prevent virus spread and will shorten the time for contam...

  2. Rigid amphipathic fusion inhibitors demonstrate antiviral activity against African swine fever virus.

    Science.gov (United States)

    Hakobyan, Astghik; Galindo, Inmaculada; Nañez, Almudena; Arabyan, Erik; Karalyan, Zaven; Chistov, Alexey A; Streshnev, Philipp P; Korshun, Vladimir A; Alonso, Covadonga; Zakaryan, Hovakim

    2018-01-01

    Rigid amphipathic fusion inhibitors (RAFIs) are a family of nucleoside derivatives that inhibit the infectivity of several enveloped viruses by interacting with virion envelope lipids and inhibiting fusion between viral and cellular membranes. Here we tested the antiviral activity of two RAFIs, 5-(Perylen-3-ylethynyl)-arabino-uridine (aUY11) and 5-(Perylen-3-ylethynyl)uracil-1-acetic acid (cm1UY11) against African swine fever virus (ASFV), for which no effective vaccine is available. Both compounds displayed a potent, dose-dependent inhibitory effect on ASFV infection in Vero cells. The major antiviral effect was observed when aUY11 and cm1UY11 were added at early stages of infection and maintained during the complete viral cycle. Furthermore, virucidal assay revealed a significant extracellular anti-ASFV activity for both compounds. We also found decrease in the synthesis of early and late viral proteins in Vero cells treated with cm1UY11. Finally, the inhibitory effect of aUY11 and cm1UY11 on ASFV infection in porcine alveolar macrophages was confirmed. Overall, our study has identified novel anti-ASFV compounds with potential for future therapeutic developments.

  3. The untranslated regions of classic swine fever virus RNA trigger apoptosis.

    Directory of Open Access Journals (Sweden)

    Wei-Li Hsu

    Full Text Available Classical swine fever virus (CSFV causes a broad range of disease in pigs, from acute symptoms including high fever and hemorrhages, to chronic disease or unapparent infection, depending on the virus strain. CSFV belongs to the genus Pestivirus of the family Flaviviridae. It carries a single-stranded positive-sense RNA genome. An internal ribosomal entry site (IRES in the 5' untranslated region (UTR drives the translation of a single open reading frame encoding a 3898 amino acid long polypeptide chain. The open reading frame is followed by a 3' UTR comprising four highly structured stem-loops. In the present study, a synthetic RNA composed of the 5' and 3' UTRs of the CSFV genome devoid of any viral coding sequence and separated by a luciferase gene cassette (designated 5'UTR-Luc-3'UTR triggered apoptotic cell death as early as 4 h post-transfection. The apoptosis was measured by DNA laddering analysis, TUNEL assay, annexin-V binding determined by flow cytometry, and by analysis of caspase activation. Contrasting with this, only trace DNA laddering was observed in cells transfected with the individual 5' or 3' UTR RNA; even when the 5' UTR and 3' UTR were co-transfected as separate RNA molecules, DNA laddering did not reach the level induced by the chimeric 5'UTR-Luc-3'UTR RNA. Interestingly, RNA composed of the 5'UTR and of stem-loop I of the 3'UTR triggered much stronger apoptosis than the 5' or 3'UTR alone. These results indicate that the 5' and 3' UTRs act together in cis induce apoptosis. We furthered obtained evidence that the UTR-mediated apoptosis required double-stranded RNA and involved translation shutoff possibly through activation of PKR.

  4. Recoding structural glycoprotein E2 in classical swine fever virus (CSFV) produces complete virus attenuation in swine and protects infected animals against disease.

    Science.gov (United States)

    Velazquez-Salinas, Lauro; Risatti, Guillermo R; Holinka, Lauren G; O'Donnell, Vivian; Carlson, Jolene; Alfano, Marialexia; Rodriguez, Luis L; Carrillo, Consuelo; Gladue, Douglas P; Borca, Manuel V

    2016-07-01

    Controlling classical swine fever (CSF) mainly involves vaccination with live attenuated vaccines (LAV). Experimental CSFV LAVs has been lately developed through reverse genetics using several different approaches. Here we present that codon de-optimization in the major CSFV structural glycoprotein E2 coding region, causes virus attenuation in swine. Four different mutated constructs (pCSFm1-pCSFm4) were designed using various mutational approaches based on the genetic background of the highly virulent strain Brescia (BICv). Three of these constructs produced infectious viruses (CSFm2v, CSFm3v, and CSFm4v). Animals infected with CSFm2v presented a reduced and extended viremia but did not display any CSF-related clinical signs. Animals that were infected with CSFm2v were protected against challenge with virulent parental BICv. This is the first report describing the development of an attenuated CSFV experimental vaccine by codon usage de-optimization, and one of the few examples of virus attenuation using this methodology that is assessed in a natural host. Published by Elsevier Inc.

  5. Detection of African swine fever, classical swine fever, and foot-and-mouth disease viruses in swine oral fluids by multiplex reverse transcription real-time polymerase chain reaction.

    Science.gov (United States)

    Grau, Frederic R; Schroeder, Megan E; Mulhern, Erin L; McIntosh, Michael T; Bounpheng, Mangkey A

    2015-03-01

    African swine fever (ASF), classical swine fever (CSF), and foot-and-mouth disease (FMD) are highly contagious animal diseases of significant economic importance. Pigs infected with ASF and CSF viruses (ASFV and CSFV) develop clinical signs that may be indistinguishable from other diseases. Likewise, various causes of vesicular disease can mimic clinical signs caused by the FMD virus (FMDV). Early detection is critical to limiting the impact and spread of these disease outbreaks, and the ability to perform herd-level surveillance for all 3 diseases rapidly and cost effectively using a single diagnostic sample and test is highly desirable. This study assessed the feasibility of simultaneous ASFV, CSFV, and FMDV detection by multiplex reverse transcription real-time polymerase chain reaction (mRT-qPCR) in swine oral fluids collected through the use of chewing ropes. Animal groups were experimentally infected independently with each virus, observed for clinical signs, and oral fluids collected and tested throughout the course of infection. All animal groups chewed on the ropes readily before and after onset of clinical signs and before onset of lameness or serious clinical signs. ASFV was detected as early as 3 days postinoculation (dpi), 2-3 days before onset of clinical disease; CSFV was detected at 5 dpi, coincident with onset of clinical disease; and FMDV was detected as early as 1 dpi, 1 day before the onset of clinical disease. Equivalent results were observed in 4 independent studies and demonstrate the feasibility of oral fluids and mRT-qPCR for surveillance of ASF, CSF, and FMD in swine populations. © 2015 The Author(s).

  6. Evaluation of classical swine fever virus antibody detection assays with an emphasis on the differentiation of infected from vaccinated animals

    DEFF Research Database (Denmark)

    Schroeder, S.; von Rosen, Tanya; Blome, S.

    2012-01-01

    vaccinated animals (DIVA). The Chekit* CSF-Sero and the HerdChek* CSFV Ab, both of which detect antibodies against the E2 protein of classical swine fever virus (CSFV), had the highest sensitivity. Both tests were practicable and showed good reproducibility. Comparable sensitivity was shown by the Chekit......The aim of this study was to evaluate the general characteristics of commercially available enzyme-linked immunosorbent assays (ELISAs) to detect antibody against classical swine fever (CSF), as well as to assess their potential use as accompanying marker tests able to differentiate infected from......* CSF-Marker, an Erns ELISA. However, this test does not allow differentiation between antibodies directed against ruminant pestiviruses and those against CSFV. Therefore, it is not suitable for use with the chimeric marker vaccines tested. The PrioCHECK® CSFV Erns was the only ELISA suitable for use...

  7. Classical swine fever virus induces pyroptosis in the peripheral lymphoid organs of infected pigs.

    Science.gov (United States)

    Yuan, Jin; Zhu, Mengjiao; Deng, Shaofeng; Fan, Shuangqi; Xu, Hailuan; Liao, Jiedan; Li, Peng; Zheng, Jingfang; Zhao, Mingqiu; Chen, Jinding

    2018-05-02

    Classical swine fever virus (CSFV) causes a highly lethal disease in pigs, which is characterized by immunosuppression. Leukopenia is known to be a possible mechanism of immunosuppression during CSFV infection. As a new and specialized form of cell death, pyroptosis is the key response of the innate immune system to pathogens, and is widely involved in the occurrence and development of infectious diseases. However, the relationship between CSFV and pyroptosis has not been explored. In this study, we investigated the occurrence of pyroptosis in pigs following CSFV infection. According to qRT-PCR assay results, the prevalence of this virus in peripheral lymphoid organs (tonsils, lymph nodes, and spleen) was much higher than that in other organs. Severe bleeding, necrosis, and a significant reduction in lymphocytes were found in the peripheral lymphoid organs of CSFV-infected pigs based on histological examination. In-depth studies showed that an increased ratio of deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL)-positive cells were present in the peripheral lymphoid organs of the CSFV-infected group according to immunohistochemistry. Meanwhile, the p10 subunit and activity of caspase-1, which is a regulator of pyroptosis, the N-terminal domain of gasdermin D, which is an executor of pyroptosis, and the cleavage and secretion of IL-1b, which is a product of pyroptosis were increased in the peripheral lymphoid organs of the CSFV-infected group. Together, these results demonstrated that pyroptosis is involved in CSFV-induced cell death in vivo, which provides a new understanding of the mechanism associated with lymphocyte depletion and immunosuppression in pigs infected with this virus. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Third wave of African swine fever infection in Armenia: Virus demonstrates the reduction of pathogenicity

    Science.gov (United States)

    Sargsyan, M. A.; Voskanyan, H. E.; Karalova, E. M.; Hakobyan, L. H.; Karalyan, Z. A.

    2018-01-01

    Aim: First cases of clinically uncommon African swine fever (ASF), caused by virus genotype II are described in this article. These cases occurred in Armenia, Tavush region, Dilijan municipality in 2011. The aim of this study was to identify and describe the new pathogenic forms of ASF in Armenia. Materials and Methods: The isolation and identification of ASF virus (ASFV) were carried out using conventional techniques. Clinical signs of infection were recorded daily. Gross anatomical pathology characteristics were observed during routine postmortem examinations. Blood and serum were obtained by puncture of the jugular vein using a vacutainer system. Results: The presence of ASFV DNA in the spleens was confirmed by polymerase chain reaction. Sequenced sections of p72 showed phylogenetic identity to genotype 2. The pathology exhibits unusual manifestations of the main disease. The unusual form of ASF demonstrates characteristics of a subacute form of the disease, with the possibility of conversion to a chronic form. Decreased lethality, low level of hemorrhages, and absence of severe pancytopenia in smears from spleen, lymph nodes, and blood are common features of the new form of ASF. Unlike severe thrombocytopenia in the typical ASF, the unusual form exhibited moderate or minor decrease of this feature. Despite a moderate decrease in hemadsorption titers, the unusual pattern of the disease was characterized by viremia and the presence of the virus in the visceral organs, including the brain. Conclusion: Our data allow assuming that new nosological form of ASF (genotype II) may present as a transitional form of the disease with the possibility of chronization. PMID:29479149

  9. Short communication: Stability and integrity of classical swine fever virus RNA stored at room temperature

    Directory of Open Access Journals (Sweden)

    Damarys Relova

    2017-12-01

    Full Text Available Worldwide cooperation between laboratories working with classical swine fever virus (CSFV requires exchange of virus isolates. For this purpose, shipment of CSFV RNA is a safe alternative to the exchange of infectious material. New techniques using desiccation have been developed to store RNA at room temperature and are reported as effective means of preserving RNA integrity. In this study, we evaluated the stability and integrity of dried CSFV RNA stored at room temperature. First, we determined the stability of CSFV RNA covering CSFV genome regions used typically for the detection of viral RNA in diagnostic samples by reverse transcription-polymerase chain reaction (RT-PCR. To this end, different concentrations of in vitro-transcribed RNAs of the 5’-untranslated region and of the NS5B gene were stored as dried RNA at 4, 20, and 37oC for two months. Aliquots were analyzed every week by CSFV-specific quantitative real-time RT-PCR. Neither the RNA concentration nor the storage temperature did affect CSFV RNA yields at any of the time evaluated until the end of the experiment. Furthermore, it was possible to recover infectious CSFV after transfection of SK-6 cells with dried viral RNA stored at room temperature for one week. The full-length E2 of CSFV was amplified from all the recovered viruses, and nucleotide sequence analysis revealed 100% identity with the corresponding sequence obtained from RNA of the original material. These results show that CSFV RNA stored as dried RNA at room temperature is stable, maintaining its integrity for downstream analyses and applications.

  10. Third wave of African swine fever infection in Armenia: Virus demonstrates the reduction of pathogenicity

    Directory of Open Access Journals (Sweden)

    M. A. Sargsyan

    2018-01-01

    Full Text Available Aim: First cases of clinically uncommon African swine fever (ASF, caused by virus genotype II are described in this article. These cases occurred in Armenia, Tavush region, Dilijan municipality in 2011. The aim of this study was to identify and describe the new pathogenic forms of ASF in Armenia. Materials and Methods: The isolation and identification of ASF virus (ASFV were carried out using conventional techniques. Clinical signs of infection were recorded daily. Gross anatomical pathology characteristics were observed during routine postmortem examinations. Blood and serum were obtained by puncture of the jugular vein using a vacutainer system. Results: The presence of ASFV DNA in the spleens was confirmed by polymerase chain reaction. Sequenced sections of p72 showed phylogenetic identity to genotype 2. The pathology exhibits unusual manifestations of the main disease. The unusual form of ASF demonstrates characteristics of a subacute form of the disease, with the possibility of conversion to a chronic form. Decreased lethality, low level of hemorrhages, and absence of severe pancytopenia in smears from spleen, lymph nodes, and blood are common features of the new form of ASF. Unlike severe thrombocytopenia in the typical ASF, the unusual form exhibited moderate or minor decrease of this feature. Despite a moderate decrease in hemadsorption titers, the unusual pattern of the disease was characterized by viremia and the presence of the virus in the visceral organs, including the brain. Conclusion: Our data allow assuming that new nosological form of ASF (genotype II may present as a transitional form of the disease with the possibility of chronization.

  11. Postnatal persistent infection with classical Swine Fever virus and its immunological implications.

    Directory of Open Access Journals (Sweden)

    Sara Muñoz-González

    Full Text Available It is well established that trans-placental transmission of classical swine fever virus (CSFV during mid-gestation can lead to persistently infected offspring. The aim of the present study was to evaluate the ability of CSFV to induce viral persistence upon early postnatal infection. Two litters of 10 piglets each were infected intranasally on the day of birth with low and moderate virulence CSFV isolates, respectively. During six weeks after postnatal infection, most of the piglets remained clinically healthy, despite persistent high virus titres in the serum. Importantly, these animals were unable to mount any detectable humoral and cellular immune response. At necropsy, the most prominent gross pathological lesion was a severe thymus atrophy. Four weeks after infection, PBMCs from the persistently infected seronegative piglets were unresponsive to both, specific CSFV and non-specific PHA stimulation in terms of IFN-γ-producing cells. These results suggested the development of a state of immunosuppression in these postnatally persistently infected pigs. However, IL-10 was undetectable in the sera of the persistently infected animals. Interestingly, CSFV-stimulated PBMCs from the persistently infected piglets produced IL-10. Nevertheless, despite the addition of the anti-IL-10 antibody in the PBMC culture from persistently infected piglets, the response of the IFN-γ producing cells was not restored. Therefore, other factors than IL-10 may be involved in the general suppression of the T-cell responses upon CSFV and mitogen activation. Interestingly, bone marrow immature granulocytes were increased and targeted by the virus in persistently infected piglets. Taken together, we provided the first data demonstrating the feasibility of CSFV in generating a postnatal persistent disease, which has not been shown for other members of the Pestivirus genus yet. Since serological methods are routinely used in CSFV surveillance, persistently infected pigs

  12. Evidence of hemolysis in pigs infected with highly virulent African swine fever virus

    Directory of Open Access Journals (Sweden)

    Zaven Karalyan

    2016-12-01

    Full Text Available Aim: The research was conducted to understand more profoundly the pathogenetic aspects of the acute form of the African swine fever (ASF. Materials and Methods: A total of 10 pigs were inoculated with ASF virus (ASFV (genotype II in the study of the red blood cells (RBCs, blood and urine biochemistry in the dynamics of disease. Results: The major hematological differences observed in ASFV infected pigs were that the mean corpuscular volume, mean corpuscular hemoglobin, and hematocrits were significantly decreased compared to controls, and the levels of erythropoietin were significantly increased. Also were detected the trends of decrease in RBC count at terminal stages of ASF. Analysis of blood biochemistry revealed that during ASF development, besides bilirubinemia significantly elevated levels of lactate dehydrogenase, and aspartate aminotransferase were detected. Analysis of urine biochemistry revealed the presence of bilirubinuria, proteinuria during ASF development. Proteinuria, especially at late stages of the disease reflects a severe kidney damage possible glomerulonefritis. Conclusion: The results of this study indicate the characteristics of developing hemolytic anemia observed in acute ASF (genotype II.

  13. Comparison of the protective efficacy of recombinant pseudorabies viruses against pseudorabies and classical swine fever in pigs,, influence of different promoters on gene expression and on protection

    NARCIS (Netherlands)

    Hooft, van B.J.L.; Wind, de N.; Wensvoort, G.; Kimman, T.G.; Gielkens, A.L.J.; Moormann, R.J.M.

    1996-01-01

    The glycoprotein E (gE) locus in the genome of pseudorabies virus (PRV) was used as an insertion site for the expression of glycoprotein E1 of classical swine fever virus (CSFV). Transcription of E1 in the recombinants M401, M402 or M403 was regulated by the gD promoter of PRV, the immediate early

  14. Visualization of the African swine fever virus infection in living cells by incorporation into the virus particle of green fluorescent protein-p54 membrane protein chimera

    International Nuclear Information System (INIS)

    Hernaez, Bruno; Escribano, Jose M.; Alonso, Covadonga

    2006-01-01

    Many stages of African swine fever virus infection have not yet been studied in detail. To track the behavior of African swine fever virus (ASFV) in the infected cells in real time, we produced an infectious recombinant ASFV (B54GFP-2) that expresses and incorporates into the virus particle a chimera of the p54 envelope protein fused to the enhanced green fluorescent protein (EGFP). The incorporation of the fusion protein into the virus particle was confirmed immunologically and it was determined that p54-EGFP was fully functional by confirmation that the recombinant virus made normal-sized plaques and presented similar growth curves to the wild-type virus. The tagged virus was visualized as individual fluorescent particles during the first stages of infection and allowed to visualize the infection progression in living cells through the viral life cycle by confocal microscopy. In this work, diverse potential applications of B54GFP-2 to study different aspects of ASFV infection are shown. By using this recombinant virus it was possible to determine the trajectory and speed of intracellular virus movement. Additionally, we have been able to visualize for first time the ASFV factory formation dynamics and the cytophatic effect of the virus in live infected cells. Finally, we have analyzed virus progression along the infection cycle and infected cell death as time-lapse animations

  15. Modular framework to assess the risk of African swine fever virus entry into the European Union.

    Science.gov (United States)

    Mur, Lina; Martínez-López, Beatriz; Costard, Solenne; de la Torre, Ana; Jones, Bryony A; Martínez, Marta; Sánchez-Vizcaíno, Fernando; Muñoz, María Jesús; Pfeiffer, Dirk U; Sánchez-Vizcaíno, José Manuel; Wieland, Barbara

    2014-07-03

    The recent occurrence and spread of African swine fever (ASF) in Eastern Europe is perceived as a serious risk for the pig industry in the European Union (EU). In order to estimate the potential risk of ASF virus (ASFV) entering the EU, several pathways of introduction were previously assessed separately. The present work aimed to integrate five of these assessments (legal imports of pigs, legal imports of products, illegal imports of products, fomites associated with transport and wild boar movements) into a modular tool that facilitates the visualization and comprehension of the relative risk of ASFV introduction into the EU by each analyzed pathway. The framework's results indicate that 48% of EU countries are at relatively high risk (risk score 4 or 5 out of 5) for ASFV entry for at least one analyzed pathway. Four of these countries obtained the maximum risk score for one pathway: Bulgaria for legally imported products during the high risk period (HRP); Finland for wild boar; Slovenia and Sweden for legally imported pigs during the HRP. Distribution of risk considerably differed from one pathway to another; for some pathways, the risk was concentrated in a few countries (e.g., transport fomites), whereas other pathways incurred a high risk for 4 or 5 countries (legal pigs, illegal imports and wild boar). The modular framework, developed to estimate the risk of ASFV entry into the EU, is available in a public domain, and is a transparent, easy-to-interpret tool that can be updated and adapted if required. The model's results determine the EU countries at higher risk for each ASFV introduction route, and provide a useful basis to develop a global coordinated program to improve ASFV prevention in the EU.

  16. A Mathematical Model that Simulates Control Options for African Swine Fever Virus (ASFV.

    Directory of Open Access Journals (Sweden)

    Mike B Barongo

    Full Text Available A stochastic model designed to simulate transmission dynamics of African swine fever virus (ASFV in a free-ranging pig population under various intervention scenarios is presented. The model was used to assess the relative impact of the timing of the implementation of different control strategies on disease-related mortality. The implementation of biosecurity measures was simulated through incorporation of a decay function on the transmission rate. The model predicts that biosecurity measures implemented within 14 days of the onset of an epidemic can avert up to 74% of pig deaths due to ASF while hypothetical vaccines that confer 70% immunity when deployed prior to day 14 of the epidemic could avert 65% of pig deaths. When the two control measures are combined, the model predicts that 91% of the pigs that would have otherwise succumbed to the disease if no intervention was implemented would be saved. However, if the combined interventions are delayed (defined as implementation from > 60 days only 30% of ASF-related deaths would be averted. In the absence of vaccines against ASF, we recommend early implementation of enhanced biosecurity measures. Active surveillance and use of pen-side diagnostic assays, preferably linked to rapid dissemination of this data to veterinary authorities through mobile phone technology platforms are essential for rapid detection and confirmation of ASF outbreaks. This prediction, although it may seem intuitive, rationally confirms the importance of early intervention in managing ASF epidemics. The modelling approach is particularly valuable in that it determines an optimal timing for implementation of interventions in controlling ASF outbreaks.

  17. Sensitive detection of African swine fever virus using real-time PCR with a 5' conjugated minor groove binding probe

    DEFF Research Database (Denmark)

    McKillan, John; McMenamy, Michael; Hjertner, Bernt

    2010-01-01

    sensitive than the conventional PCR recommended by the OIE. Linear range was ten logs from 2 × 101 to 2 × 1010. The assay is rapid with an amplification time just over 2 h. The development of this assay provides a useful tool for the specific diagnosis of ASF in statutory or emergency testing programs......The design of a 5′ conjugated minor groove binder (MGB) probe real-time PCR assay is described for the rapid, sensitive and specific detection of African swine fever virus (ASFV) DNA. The assay is designed against the 9GL region and is capable of detecting 20 copies of a DNA standard. It does...

  18. Evolution and molecular epidemiology of classical swine fever virus during a multi-annual outbreak amongst European wild boar.

    Science.gov (United States)

    Goller, Katja V; Gabriel, Claudia; Dimna, Mireille Le; Le Potier, Marie-Frédérique; Rossi, Sophie; Staubach, Christoph; Merboth, Matthias; Beer, Martin; Blome, Sandra

    2016-03-01

    Classical swine fever is a viral disease of pigs that carries tremendous socio-economic impact. In outbreak situations, genetic typing is carried out for the purpose of molecular epidemiology in both domestic pigs and wild boar. These analyses are usually based on harmonized partial sequences. However, for high-resolution analyses towards the understanding of genetic variability and virus evolution, full-genome sequences are more appropriate. In this study, a unique set of representative virus strains was investigated that was collected during an outbreak in French free-ranging wild boar in the Vosges-du-Nord mountains between 2003 and 2007. Comparative sequence and evolutionary analyses of the nearly full-length sequences showed only slow evolution of classical swine fever virus strains over the years and no impact of vaccination on mutation rates. However, substitution rates varied amongst protein genes; furthermore, a spatial and temporal pattern could be observed whereby two separate clusters were formed that coincided with physical barriers.

  19. Early intranuclear replication of African swine fever virus genome modifies the landscape of the host cell nucleus.

    Science.gov (United States)

    Simões, Margarida; Martins, Carlos; Ferreira, Fernando

    2015-12-02

    Although African swine fever virus (ASFV) replicates in viral cytoplasmic factories, the presence of viral DNA within the host cell nucleus has been previously reported to be essential for productive infection. Herein, we described, for the first time, the intranuclear distribution patterns of viral DNA replication events, preceding those that occur in the cytoplasmic compartment. Using BrdU pulse-labelling experiments, newly synthesized ASFV genomes were exclusively detected inside the host cell nucleus at the early phase of infection, both in swine monocyte-derived macrophages (MDMs) and Vero cells. From 8hpi onwards, BrdU labelling was only observed in ASFV cytoplasmic factories. Our results also show that ASFV specifically activates the Ataxia Telangiectasia Mutated Rad-3 related (ATR) pathway in ASFV-infected swine MDMs from the early phase of infection, most probably because ASFV genome is recognized as foreign DNA. Morphological changes of promyelocytic leukaemia nuclear bodies (PML-NBs), nuclear speckles and Cajal bodies were also found in ASFV-infected swine MDMs, strongly suggesting the viral modulation of cellular antiviral responses and cellular transcription, respectively. As described for other viral infections, the nuclear reorganization that takes place during ASFV infection may also provide an environment that favours its intranuclear replication events. Altogether, our results contribute for a better understanding of ASFV replication strategies, starting with an essential intranuclear DNA replication phase which induces host nucleus changes towards a successful viral infection. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. First molecular identification and characterization of classical swine fever virus isolates from Nepal.

    Science.gov (United States)

    Postel, Alexander; Jha, Vijay C; Schmeiser, Stefanie; Becher, Paul

    2013-01-01

    Classical swine fever (CSF) is a major constraint to pig production worldwide, and in many developing countries, the epidemiological status is unknown. Here, for the first time, molecular identification and characterization of CSFV isolates from two recent outbreaks in Nepal are presented. Analysis of full-length E2-encoding sequences revealed that these isolates belonged to CSFV subgenotype 2.2 and had highest genetic similarity to isolates from India. Hence, for CSFV, Nepal and India should be regarded as one epidemiological unit. Both Nepalese isolates exhibited significant sequence differences, excluding a direct epidemiological connection and suggesting that CSFV is endemic in that country.

  1. Third generation DIVA vaccine towards classical swine fever virus. Efficacy in face of maternal immunity

    DEFF Research Database (Denmark)

    Rangelova, Desislava Yordanova

    General purpose and objectives Classical swine fever (CSF) is a highly contagious disease that causes huge economical losses and animal welfare concerns worldwide. Generally, vaccination is an effective and safe method to control the disease. Following vaccination the pig’s immune system develops...... a new DIVA vaccine candidate. The vaccine candidate “CP7E2alf” is intended for either intramuscular vaccination of domestic pig or for bait vaccination of wild boar. In this thesis as part of the clinical testing of the injection vaccine the efficacy of “CP7E2alf” was evaluated in young piglets...

  2. Effective surveillance for early classical swine fever virus detection will utilize both virus and antibody detection capabilities.

    Science.gov (United States)

    Panyasing, Yaowalak; Kedkovid, Roongtham; Thanawongnuwech, Roongroje; Kittawornrat, Apisit; Ji, Ju; Giménez-Lirola, Luis; Zimmerman, Jeffrey

    2018-03-01

    Early recognition and rapid elimination of infected animals is key to controlling incursions of classical swine fever virus (CSFV). In this study, the diagnostic characteristics of 10 CSFV assays were evaluated using individual serum (n = 601) and/or oral fluid (n = 1417) samples collected from -14 to 28 days post inoculation (DPI). Serum samples were assayed by virus isolation (VI), 2 commercial antigen-capture enzyme-linked immunosorbent assays (ELISA), virus neutralization (VN), and 3 antibody ELISAs. Both serum and oral fluid samples were tested with 3 commercial real-time reverse transcription-polymerase chain reaction (rRT-PCR) assays. One or more serum samples was positive by VI from DPIs 3 to 21 and by antigen-capture ELISAs from DPIs 6 to 17. VN-positive serum samples were observed at DPIs ≥ 7 and by antibody ELISAs at DPIs ≥ 10. CSFV RNA was detected in serum samples from DPIs 2 to 28 and in oral fluid samples from DPIs 4 to 28. Significant differences in assay performance were detected, but most importantly, no single combination of sample and assay was able to dependably identify CSFV-inoculated pigs throughout the 4-week course of the study. The results show that effective surveillance for CSFV, especially low virulence strains, will require the use of PCR-based assays for the detection of early infections (<14 days) and antibody-based assays, thereafter. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. Control of African swine fever epidemics in industrialized swine populations

    DEFF Research Database (Denmark)

    Hisham Beshara Halasa, Tariq; Bøtner, Anette; Mortensen, Sten

    2016-01-01

    , it is important to explore strategies that can effectively control an epidemic of ASF. In this study, the epidemiological and economic effects of strategies to control the spread of ASF between domestic swine herds were examined using a published model (DTU-DADS-ASF). The control strategies were the basic EU...... and national strategy (Basic), the basic strategy plus pre-emptive depopulation of neighboring swine herds, and intensive surveillance of herds in the control zones, including testing live or dead animals. Virus spread via wild boar was not modelled. Under the basic control strategy, the median epidemic......African swine fever (ASF) is a notifiable infectious disease with a high impact on swine health. The disease is endemic in certain regions in the Baltic countries and has spread to Poland constituting a risk of ASF spread toward Western Europe. Therefore, as part of contingency planning...

  4. Determination of the sequence of the complete open reading frame and the 5 ' NTR of the Paderborn isolate of classical swine fever virus

    DEFF Research Database (Denmark)

    Oleksiewicz, Martin B.; Rasmussen, Thomas Bruun; Normann, Preben

    2003-01-01

    The classical swine fever (CSF) epidemic in the Netherlands in 1997-1998 lasted 14 months, during which 429 infected and 1300 at risk herds were culled, at an estimated economical cost of 2 billion US dollars. Despite the overwhelming scale of the epizootic, the CSF virus (CSFV) strain causing th...

  5. Classical swine fever virus infection modulates serum levels of INF-α, IL-8 and TNF-α in 6-month-old pigs

    DEFF Research Database (Denmark)

    von Rosen, Tanya; Lohse, Louise; Nielsen, Jens

    2013-01-01

    Several studies have highlighted the important role of cytokines in disease development of classical swine fever virus (CSFV) infection. In the present study, we examined the kinetics of 7 porcine cytokines in serum from pigs infected with 3 different CSFV strains. Based on the clinical picture i...

  6. Simulating the spread of classical swine fever virus between a hypothetical wild-boar population and domestic pig herds in Denmark

    DEFF Research Database (Denmark)

    Boklund, Anette; Goldbach, Stine G.; Uttenthal, Åse

    2008-01-01

    of CSFV between the hypothetical wild-boar population and the domestic population. Furthermore, the economic impact is assessed taking the perspective of the Danish national budget and the Danish pig industry. We used InterSpreadPlus to model the differential classical swine fever (CSF) risk due to wild......Denmark has no free-range wild-boar population. However, Danish wildlife organizations have suggested that wild boar should be reintroduced into the wild to broaden national biodiversity. Danish pig farmers fear that this would lead to a higher risk of introduction of classical swine fever virus...

  7. Detection of African swine fever virus from formalin fixed and non-fixed tissues by polymerase chain reaction

    Directory of Open Access Journals (Sweden)

    P. D. Luka

    2014-10-01

    Full Text Available Aim: Formalin fixing and paraffin embedding of tissue samples is one of the techniques for preserving the structural integrity of cells for a very long time. However, extraction and analysis of genomic material from formalin fixed tissue (FFT remains a challenge despite numerous attempts to develop a more effective method. The success of polymerase chain reaction (PCR depends on the quality of DNA extract. Materials and Methods: Here we assessed the conventional method of DNA extraction from FFT for African swine fever virus (ASFV detection. The modified conventional method gave a higher quality DNA when compared with commercially available DNA extraction kits (QIAamp® DNA Mini Kit, DNeasy® Blood and Tissue Kit, and ZR Genomic DNA™ Tissue MiniPrep. Results: An average A260/A280 DNA purity of 0.86-1.68 and 3.22-5.32 μg DNA/mg for formalin fixed and non-fixed tissues, respectively using a conventional method. In a reproducible and three times repeat PCR, the ASFV DNA expected product size of 278 bp was obtained from the DNA extract of the conventional method but not from the DNA extract of the commercial kits. Conclusion: The present study has demonstrated that the conventional method extracts ASFV genome better than commercial kit. In summary, the commercial kit extraction appeared not suitable to purify ASFV DNA from FFT. We, therefore, recommend that the use of the conventional method be considered for African swine fever DNA extraction from FFT.

  8. African Swine Fever Virus Undergoes Outer Envelope Disruption, Capsid Disassembly and Inner Envelope Fusion before Core Release from Multivesicular Endosomes.

    Directory of Open Access Journals (Sweden)

    Bruno Hernáez

    2016-04-01

    Full Text Available African swine fever virus (ASFV is a nucleocytoplasmic large DNA virus (NCLDV that causes a highly lethal disease in domestic pigs. As other NCLDVs, the extracellular form of ASFV possesses a multilayered structure consisting of a genome-containing nucleoid successively wrapped by a thick protein core shell, an inner lipid membrane, an icosahedral protein capsid and an outer lipid envelope. This structural complexity suggests an intricate mechanism of internalization in order to deliver the virus genome into the cytoplasm. By using flow cytometry in combination with pharmacological entry inhibitors, as well as fluorescence and electron microscopy approaches, we have dissected the entry and uncoating pathway used by ASFV to infect the macrophage, its natural host cell. We found that purified extracellular ASFV is internalized by both constitutive macropinocytosis and clathrin-mediated endocytosis. Once inside the cell, ASFV particles move from early endosomes or macropinosomes to late, multivesicular endosomes where they become uncoated. Virus uncoating requires acidic pH and involves the disruption of the outer membrane as well as of the protein capsid. As a consequence, the inner viral membrane becomes exposed and fuses with the limiting endosomal membrane to release the viral core into the cytosol. Interestingly, virus fusion is dependent on virus protein pE248R, a transmembrane polypeptide of the inner envelope that shares sequence similarity with some members of the poxviral entry/fusion complex. Collective evidence supports an entry model for ASFV that might also explain the uncoating of other multienveloped icosahedral NCLDVs.

  9. Remarkable sequence similarity between the dinoflagellate-infecting marine girus and the terrestrial pathogen African swine fever virus

    Directory of Open Access Journals (Sweden)

    Claverie Jean-Michel

    2009-10-01

    Full Text Available Abstract Heterocapsa circularisquama DNA virus (HcDNAV; previously designated as HcV is a giant virus (girus with a ~356-kbp double-stranded DNA (dsDNA genome. HcDNAV lytically infects the bivalve-killing marine dinoflagellate H. circularisquama, and currently represents the sole DNA virus isolated from dinoflagellates, one of the most abundant protists in marine ecosystems. Its morphological features, genome type, and host range previously suggested that HcDNAV might be a member of the family Phycodnaviridae of Nucleo-Cytoplasmic Large DNA Viruses (NCLDVs, though no supporting sequence data was available. NCLDVs currently include two families found in aquatic environments (Phycodnaviridae, Mimiviridae, one mostly infecting terrestrial animals (Poxviridae, another isolated from fish, amphibians and insects (Iridoviridae, and the last one (Asfarviridae exclusively represented by the animal pathogen African swine fever virus (ASFV, the agent of a fatal hemorrhagic disease in domestic swine. In this study, we determined the complete sequence of the type B DNA polymerase (PolB gene of HcDNAV. The viral PolB was transcribed at least from 6 h post inoculation (hpi, suggesting its crucial function for viral replication. Most unexpectedly, the HcDNAV PolB sequence was found to be closely related to the PolB sequence of ASFV. In addition, the amino acid sequence of HcDNAV PolB showed a rare amino acid substitution within a motif containing highly conserved motif: YSDTDS was found in HcDNAV PolB instead of YGDTDS in most dsDNA viruses. Together with the previous observation of ASFV-like sequences in the Sorcerer II Global Ocean Sampling metagenomic datasets, our results further reinforce the ideas that the terrestrial ASFV has its evolutionary origin in marine environments.

  10. Overview of Classical Swine Fever (Hog Cholera, Classical Swine fever)

    Science.gov (United States)

    Classical swine fever is a contagious often fatal disease of pigs clinically characterized by high body temperature, lethargy, yellowish diarrhea, vomits and purple skin discoloration of ears, lower abdomen and legs. It was first described in the early 19th century in the USA. Later, a condition i...

  11. Comprehensive analysis of the codon usage patterns in the envelope glycoprotein E2 gene of the classical swine fever virus.

    Directory of Open Access Journals (Sweden)

    Ye Chen

    Full Text Available The classical swine fever virus (CSFV, circulating worldwide, is a highly contagious virus. Since the emergence of CSFV, it has caused great economic loss in swine industry. The envelope glycoprotein E2 gene of the CSFV is an immunoprotective antigen that induces the immune system to produce neutralizing antibodies. Therefore, it is essential to study the codon usage of the E2 gene of the CSFV. In this study, 140 coding sequences of the E2 gene were analyzed. The value of effective number of codons (ENC showed low codon usage bias in the E2 gene. Our study showed that codon usage could be described mainly by mutation pressure ENC plot analysis combined with principal component analysis (PCA and translational selection-correlation analysis between the general average hydropathicity (Gravy and aromaticity (Aroma, and nucleotides at the third position of codons (A3s, T3s, G3s, C3s and GC3s. Furthermore, the neutrality analysis, which explained the relationship between GC12s and GC3s, revealed that natural selection had a key role compared with mutational bias during the evolution of the E2 gene. These results lay a foundation for further research on the molecular evolution of CSFV.

  12. A Review of Classical Swine Fever Virus and Routes of Introduction into the United States and the Potential for Virus Establishment

    Directory of Open Access Journals (Sweden)

    Vienna R. Brown

    2018-03-01

    Full Text Available Classical swine fever (CSF is caused by CSF virus (CSFV which can be the source of substantial morbidity and mortality events in affected swine. The disease can take one of several forms (acute, chronic, or prenatal and depending on the virulence of the inoculating strain may result in a lethal infection irrespective of the form acquired. Because of the disease-free status of the United States and the high cost of a viral incursion, a summary of US vulnerabilities for viral introduction and persistence is provided. The legal importation of live animals as well as animal products, byproducts, and animal feed serve as a potential route of viral introduction. Current import regulations are described as are mitigation strategies that are commonly utilized to prevent pathogens, including CSFV, from entering the US. The illegal movement of suids and their products as well as an event of bioterrorism are both feasible routes of viral introduction but are difficult to restrict or regulate. Ultimately, recommendations are made for data that would be useful in the event of a viral incursion. Population and density mapping for feral swine across the United States would be valuable in the event of a viral introduction or spillover; density data could further contribute to understanding the risk of infection in domestic swine. Additionally, ecological and behavioral studies, including those that evaluate the effects of anthropogenic food sources that support feral swine densities far above the carrying capacity would provide invaluable insight to our understanding of how human interventions affect feral swine populations. Further analyses to determine the sampling strategies necessary to detect low levels of antibody prevalence in feral swine would also be valuable.

  13. A Review of Classical Swine Fever Virus and Routes of Introduction into the United States and the Potential for Virus Establishment.

    Science.gov (United States)

    Brown, Vienna R; Bevins, Sarah N

    2018-01-01

    Classical swine fever (CSF) is caused by CSF virus (CSFV) which can be the source of substantial morbidity and mortality events in affected swine. The disease can take one of several forms (acute, chronic, or prenatal) and depending on the virulence of the inoculating strain may result in a lethal infection irrespective of the form acquired. Because of the disease-free status of the United States and the high cost of a viral incursion, a summary of US vulnerabilities for viral introduction and persistence is provided. The legal importation of live animals as well as animal products, byproducts, and animal feed serve as a potential route of viral introduction. Current import regulations are described as are mitigation strategies that are commonly utilized to prevent pathogens, including CSFV, from entering the US. The illegal movement of suids and their products as well as an event of bioterrorism are both feasible routes of viral introduction but are difficult to restrict or regulate. Ultimately, recommendations are made for data that would be useful in the event of a viral incursion. Population and density mapping for feral swine across the United States would be valuable in the event of a viral introduction or spillover; density data could further contribute to understanding the risk of infection in domestic swine. Additionally, ecological and behavioral studies, including those that evaluate the effects of anthropogenic food sources that support feral swine densities far above the carrying capacity would provide invaluable insight to our understanding of how human interventions affect feral swine populations. Further analyses to determine the sampling strategies necessary to detect low levels of antibody prevalence in feral swine would also be valuable.

  14. The progressive adaptation of a georgian isolate of African swine fever virus to vero cells leads to a gradual attenuation of virulence in swine corresponding to major modifications of the viral genome.

    Science.gov (United States)

    Krug, Peter W; Holinka, Lauren G; O'Donnell, Vivian; Reese, Bo; Sanford, Brenton; Fernandez-Sainz, Ignacio; Gladue, Douglas P; Arzt, Jonathan; Rodriguez, Luis; Risatti, Guillermo R; Borca, Manuel V

    2015-02-01

    African swine fever virus (ASFV) causes a contagious and often lethal disease of feral and domestic swine. Experimental vaccines derived from naturally occurring, genetically modified, or cell culture-adapted ASFV have been evaluated, but no commercial vaccine is available to control African swine fever (ASF). We report here the genotypic and phenotypic analysis of viruses obtained at different passages during the process of adaptation of a virulent ASFV field isolate from the Republic of Georgia (ASFV-G) to grow in cultured cell lines. ASFV-G was successively passaged 110 times in Vero cells. Viruses obtained at passages 30, 60, 80, and 110 were evaluated in vitro for the ability to replicate in Vero cells and primary swine macrophages cultures and in vivo for assessing virulence in swine. Replication of ASFV-G in Vero cells increased with successive passages, corresponding to a decreased replication in primary swine macrophages cultures. In vivo, progressive loss of virus virulence was observed with increased passages in Vero cells, and complete attenuation of ASFV-G was observed at passage 110. Infection of swine with the fully attenuated virus did not confer protection against challenge with virulent parental ASFV-G. Full-length sequence analysis of each of these viruses revealed significant deletions that gradually accumulated in specific areas at the right and left variable ends of the genome. Mutations that result in amino acid substitutions and frameshift mutations were also observed, though in a rather limited number of genes. The potential importance of these genetic changes in virus adaptation/attenuation is discussed. The main problem in controlling ASF is the lack of vaccines. Attempts to produce vaccines by adaptation of ASFV to cultured cell lines have been made. These attempts led to the production of attenuated viruses that conferred only homologous protection. Specifics regarding adaptation of these isolates to cell cultures have been

  15. Immunogenicity in Swine of Orally Administered Recombinant Lactobacillus plantarum Expressing Classical Swine Fever Virus E2 Protein in Conjunction with Thymosin α-1 as an Adjuvant

    Science.gov (United States)

    Xu, Yi-Gang; Guan, Xue-Ting; Liu, Zhong-Mei; Tian, Chang-Yong

    2015-01-01

    Classical swine fever, caused by classical swine fever virus (CSFV), is a highly contagious disease that results in enormous economic losses in pig industries. The E2 protein is one of the main structural proteins of CSFV and is capable of inducing CSFV-neutralizing antibodies and cytotoxic T lymphocyte (CTL) activities in vivo. Thymosin α-1 (Tα1), an immune-modifier peptide, plays a very important role in the cellular immune response. In this study, genetically engineered Lactobacillus plantarum bacteria expressing CSFV E2 protein alone (L. plantarum/pYG-E2) and in combination with Tα1 (L. plantarum/pYG-E2-Tα1) were developed, and the immunogenicity of each as an oral vaccine to induce protective immunity against CSFV in pigs was evaluated. The results showed that recombinant L. plantarum/pYG-E2 and L. plantarum/pYG-E2-Tα1 were both able to effectively induce protective immune responses in pigs against CSFV infection by eliciting immunoglobulin A (IgA)-based mucosal, immunoglobulin G (IgG)-based humoral, and CTL-based cellular immune responses via oral vaccination. Significant differences (P plantarum/pYG-E2-Tα1 and L. plantarum/pYG-E2, suggesting a better immunogenicity of L. plantarum/pYG-E2-Tα1 as a result of the Tα1 molecular adjuvant that can enhance immune responsiveness and augment specific lymphocyte functions. Our data suggest that the recombinant Lactobacillus microecological agent expressing CSFV E2 protein combined with Tα1 as an adjuvant provides a promising strategy for vaccine development against CSFV. PMID:25819954

  16. An avirulent chimeric Pestivirus with altered cell tropism protects pigs against lethal infection with classical swine fever virus

    International Nuclear Information System (INIS)

    Reimann, Ilona; Depner, Klaus; Trapp, Sascha; Beer, Martin

    2004-01-01

    A chimeric Pestivirus was constructed using an infectious cDNA clone of bovine viral diarrhea virus (BVDV) [J. Virol. 70 (1996) 8606]. After deletion of the envelope protein E2-encoding region, the respective sequence of classical swine fever virus (CSFV) strain Alfort 187 was inserted in-frame resulting in plasmid pA/CP7 E 2alf. After transfection of in vitro-transcribed CP7 E 2alf RNA, autonomous replication of chimeric RNA in bovine and porcine cell cultures was observed. Efficient growth of chimeric CP7 E 2alf virus, however, could only be demonstrated on porcine cells, and in contrast to the parental BVDV strain CP7, CP7 E 2alf only inefficiently infected and propagated in bovine cells. The virulence, immunogenicity, and 'marker vaccine' properties of the generated chimeric CP7 E 2alf virus were determined in an animal experiment using 27 pigs. After intramuscular inoculation of 1 x 10 7 TCID 50 , CP7 E 2alf proved to be completely avirulent, and neither viremia nor virus transmission to contact animals was observed; however, CSFV-specific neutralizing antibodies were detected from day 11 after inoculation. In addition, sera from all animals reacted positive in an E2-specific CSFV-antibody ELISA, but were negative for CSFV-E RNS -specific antibodies as determined with a CSFV marker ELISA. After challenge infection with highly virulent CSFV strain Eystrup, pigs immunized with CP7 E 2alf were fully protected against clinical signs of CSFV infection, viremia, and shedding of challenge virus, and almost all animals scored positive in a CSFV marker ELISA. From our results, we conclude that chimeric CP7 E 2alf may not only serve as a tool for a better understanding of Pestivirus attachment, entry, and assembly, but also represents an innocuous and efficacious modified live CSFV 'marker vaccine'

  17. Porcine Mx1 Protein Inhibits Classical Swine Fever Virus Replication by Targeting Nonstructural Protein NS5B.

    Science.gov (United States)

    Zhou, Jing; Chen, Jing; Zhang, Xiao-Min; Gao, Zhi-Can; Liu, Chun-Chun; Zhang, Yun-Na; Hou, Jin-Xiu; Li, Zhao-Yao; Kan, Lin; Li, Wen-Liang; Zhou, Bin

    2018-04-01

    Mx proteins are interferon (IFN)-induced GTPases that have broad antiviral activity against a wide range of RNA and DNA viruses; they belong to the dynamin superfamily of large GTPases. In this study, we confirmed the anti-classical swine fever virus (CSFV) activity of porcine Mx1 in vitro and showed that porcine Mx2 (poMx2), human MxA (huMxA), and mouse Mx1 (mmMx1) also have anti-CSFV activity in vitro Small interfering RNA (siRNA) experiments revealed that depletion of endogenous poMx1 or poMx2 enhanced CSFV replication, suggesting that porcine Mx proteins are responsible for the antiviral activity of interferon alpha (IFN-α) against CSFV infection. Confocal microscopy, immunoprecipitation, glutathione S -transferase (GST) pulldown, and bimolecular fluorescence complementation (BiFC) demonstrated that poMx1 associated with NS5B, the RNA-dependent RNA polymerase (RdRp) of CSFV. We used mutations in the poMx1 protein to elucidate the mechanism of their anti-CSFV activity and found that mutants that disrupted the association with NS5B lost all anti-CSV activity. Moreover, an RdRp activity assay further revealed that poMx1 undermined the RdRp activities of NS5B. Together, these results indicate that porcine Mx proteins exert their antiviral activity against CSFV by interacting with NS5B. IMPORTANCE Our previous studies have shown that porcine Mx1 (poMx1) inhibits classical swine fever virus (CSFV) replication in vitro and in vivo , but the molecular mechanism of action remains largely unknown. In this study, we dissect the molecular mechanism of porcine Mx1 and Mx2 against CSFV in vitro Our results show that poMx1 associates with NS5B, the RNA-dependent RNA polymerase of CSFV, resulting in the reduction of CSFV replication. Moreover, the mutants of poMx1 further elucidate the mechanism of their anti-CSFV activities. Copyright © 2018 American Society for Microbiology.

  18. Efficient purification of cell culture-derived classical swine fever virus by ultrafiltration and size-exclusion chromatography

    Directory of Open Access Journals (Sweden)

    Ruining WANG,Yubao ZHI,Junqing GUO,Qingmei LI,Li WANG,Jifei YANG,Qianyue JIN,Yinbiao WANG,Yanyan YANG,Guangxu XING,Songlin QIAO,Mengmeng ZHAO,Ruiguang DENG,Gaiping ZHANG

    2015-09-01

    Full Text Available Large-scale production of cell culture-based classical swine fever virus (CSFV vaccine is hampered by the adverse reactions caused by contaminants from host cell and culture medium. Hence, we have developed an efficient method for purifying CSFV from cell-culture medium. Pure viral particles were obtained with two steps of tangential-flow filtration (TFF and size-exclusion chromatography (SEC, and were compared with particles from ultracentrifugation by transmission electron microscopy (TEM, infectivity and recovery test, and real time fluorescent quantitative PCR (FQ-PCR. TFF concentrated the virus particles effectively with a retention rate of 98.5%, and 86.2% of viral particles were obtained from the ultrafiltration retentate through a Sepharose 4 F F column on a biological liquid chromatography system. CSFV purified by TFF-SEC or ultracentrifugation were both biologically active from 1.0×10-4.25 TCID50·mL-1 to 3.0×10-6.25 TCID50·mL-1, but the combination of TFF and SEC produced more pure virus particles than by ultracentrifugation alone. In addition, pure CSFV particles with the expected diameter of 40—60 nm were roughly spherical without any visible contamination. Mice immunized with CSFV purified by TFF-SEC produced higher antibody levels compared with immunization with ultracentrifugation-purified CSFV (P<0.05. The purification procedures in this study are reliable technically and feasible for purification of large volumes of viruses.

  19. Molecular tracing of classical swine fever viruses isolated from wild boars and pigs in France from 2002 to 2011.

    Science.gov (United States)

    Simon, Gaëlle; Le Dimna, Mireille; Le Potier, Marie-Frédérique; Pol, Françoise

    2013-10-25

    There were three outbreaks of classical swine fever (CSF) in north-eastern France between 2002 and 2011. The first two occurred in April 2002 in the Moselle department, in a wild boar and pig herd, respectively, while the third occurred in April 2003, in the Bas-Rhin department, in a wild boar. A survey was subsequently implemented in wild boar and domestic pig populations, during which 43 CSF viruses (CSFVs) were genetically characterized to provide information on virus sources, trace virus evolution and help in the monitoring of effective control measures. Phylogenetic analyses, based on fragments of the 5'NTR, E2 and NS5B genes, showed that all French CSFVs could be assigned to genotype 2, subgenotype 2.3. CSFVs isolated in Moselle were classified in the "Rostock" lineage, a strain first described in 2001 in wild boar populations in the Eifel region of north-western Rhineland-Palatinate in Germany, and in Luxemburg. In contrast, the CSFVs isolated in Bas-Rhin were homologous to strains from the "Uelzen" lineage, a strain previously isolated from wild boars in south-eastern Rhineland-Palatinate, Germany, as well as in Vosges du Nord, France, during a previous outbreak that had occurred in wild boars between 1992 and 2001. The outbreak in Moselle domestic pigs was quickly resolved as it concerned only one herd. The infection in wild boars from Moselle was extinguished after a few months whereas wild boars from Bas-Rhin remained infected until 2007. Molecular tracing showed that the Bas-Rhin index virus strain evolved slightly during the period but that no strain from a novel lineage was introduced until this outbreak ended after application of a vaccination scheme for six years. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Sequence-based comparative study of classical swine fever virus genogroup 2.2 isolate with pestivirus reference strains.

    Science.gov (United States)

    Kumar, Ravi; Rajak, Kaushal Kishor; Chandra, Tribhuwan; Muthuchelvan, Dhanavelu; Saxena, Arpit; Chaudhary, Dheeraj; Kumar, Ajay; Pandey, Awadh Bihari

    2015-09-01

    This study was undertaken with the aim to compare and establish the genetic relatedness between classical swine fever virus (CSFV) genogroup 2.2 isolate and pestivirus reference strains. The available complete genome sequences of CSFV/IND/UK/LAL-290 strain and other pestivirus reference strains were retrieved from GenBank. The complete genome sequence, complete open reading frame, 5' and 3' non-coding region (NCR) sequences were analyzed and compared with reference pestiviruses strains. Clustal W model in MegAlign program of Lasergene 6.0 software was used for analysis of genetic heterogeneity. Phylogenetic analysis was carried out using MEGA 6.06 software package. The complete genome sequence alignment of CSFV/IND/UK/LAL-290 isolate and reference pestivirus strains showed 58.9-72% identities at the nucleotide level and 50.3-76.9% at amino acid level. Sequence homology of 5' and 3' NCRs was found to be 64.1-82.3% and 22.9-71.4%, respectively. In phylogenetic analysis, overall tree topology was found similar irrespective of sequences used in this study; however, whole genome phylogeny of pestivirus formed two main clusters, which further distinguished into the monophyletic clade of each pestivirus species. CSFV/IND/UK/LAL-290 isolate placed with the CSFV Eystrup strain in the same clade with close proximity to border disease virus and Aydin strains. CSFV/IND/UK/LAL-290 exhibited the analogous genomic organization to those of all reference pestivirus strains. Based on sequence identity and phylogenetic analysis, the isolate showed close homology to Aydin/04-TR virus and distantly related to Bungowannah virus.

  1. Immunogenicity of Recombinant Classic Swine Fever Virus CD8+ T Lymphocyte Epitope and Porcine Parvovirus VP2 Antigen Coexpressed by Lactobacillus casei in Swine via Oral Vaccination ▿

    Science.gov (United States)

    Xu, Yigang; Cui, Lichun; Tian, Changyong; Zhang, Guocai; Huo, Guicheng; Tang, Lijie; Li, Yijing

    2011-01-01

    Classical swine fever virus (CSFV) and porcine parvovirus (PPV) are highly contagious pathogens, resulting in enormous economic losses in pig industries worldwide. Because vaccines play an important role in disease control, researchers are seeking improved vaccines that could induce antiviral immune responses against CSFV and PPV at the mucosal and systemic levels simultaneously. In this study, a genetically engineered Lactobacillus strain coexpressing the CSFV-specific cytotoxic T lymphocyte (CTL) epitope 290 and the VP2 antigen of PPV was developed, and its immunopotentiating capacity as an oral vaccine in pigs was analyzed. The data demonstrated that in the absence of any adjuvant, the recombinant Lactobacillus strain can efficiently stimulate mucosal and systemic CSFV-specific CD8+ CTL responses to protect pigs against CSFV challenge. Moreover, anti-PPV-VP2 serum IgG and mucosal IgA were induced in pigs immunized orally with the recombinant Lactobacillus strain, showing a neutralizing effect on PPV infection. The results suggest that the recombinant Lactobacillus microecological agent may be a valuable component of a strategy for development of a vaccine against CSFV and PPV. PMID:21940406

  2. Immunization of Pigs by DNA Prime and Recombinant Vaccinia Virus Boost To Identify and Rank African Swine Fever Virus Immunogenic and Protective Proteins.

    Science.gov (United States)

    Jancovich, James K; Chapman, Dave; Hansen, Debra T; Robida, Mark D; Loskutov, Andrey; Craciunescu, Felicia; Borovkov, Alex; Kibler, Karen; Goatley, Lynnette; King, Katherine; Netherton, Christopher L; Taylor, Geraldine; Jacobs, Bertram; Sykes, Kathryn; Dixon, Linda K

    2018-04-15

    African swine fever virus (ASFV) causes an acute hemorrhagic fever in domestic pigs, with high socioeconomic impact. No vaccine is available, limiting options for control. Although live attenuated ASFV can induce up to 100% protection against lethal challenge, little is known of the antigens which induce this protective response. To identify additional ASFV immunogenic and potentially protective antigens, we cloned 47 viral genes in individual plasmids for gene vaccination and in recombinant vaccinia viruses. These antigens were selected to include proteins with different functions and timing of expression. Pools of up to 22 antigens were delivered by DNA prime and recombinant vaccinia virus boost to groups of pigs. Responses of immune lymphocytes from pigs to individual recombinant proteins and to ASFV were measured by interferon gamma enzyme-linked immunosorbent spot (ELISpot) assays to identify a subset of the antigens that consistently induced the highest responses. All 47 antigens were then delivered to pigs by DNA prime and recombinant vaccinia virus boost, and pigs were challenged with a lethal dose of ASFV isolate Georgia 2007/1. Although pigs developed clinical and pathological signs consistent with acute ASFV, viral genome levels were significantly reduced in blood and several lymph tissues in those pigs immunized with vectors expressing ASFV antigens compared with the levels in control pigs. IMPORTANCE The lack of a vaccine limits the options to control African swine fever. Advances have been made in the development of genetically modified live attenuated ASFV that can induce protection against challenge. However, there may be safety issues relating to the use of these in the field. There is little information about ASFV antigens that can induce a protective immune response against challenge. We carried out a large screen of 30% of ASFV antigens by delivering individual genes in different pools to pigs by DNA immunization prime and recombinant vaccinia

  3. Identification of Wild Boar-Habitat Epidemiologic Cycle in African Swine Fever Epizootic.

    Science.gov (United States)

    Chenais, Erika; Ståhl, Karl; Guberti, Vittorio; Depner, Klaus

    2018-04-01

    The African swine fever epizootic in central and eastern European Union member states has a newly identified component involving virus transmission by wild boar and virus survival in the environment. Insights led to an update of the 3 accepted African swine fever transmission models to include a fourth cycle: wild boar-habitat.

  4. Identification of Wild Boar–Habitat Epidemiologic Cycle in African Swine Fever Epizootic

    Science.gov (United States)

    Ståhl, Karl; Guberti, Vittorio; Depner, Klaus

    2018-01-01

    The African swine fever epizootic in central and eastern European Union member states has a newly identified component involving virus transmission by wild boar and virus survival in the environment. Insights led to an update of the 3 accepted African swine fever transmission models to include a fourth cycle: wild boar–habitat. PMID:29553337

  5. HuR binding to AU-rich elements present in the 3' untranslated region of Classical swine fever virus

    Directory of Open Access Journals (Sweden)

    Huang Chin-Cheng

    2011-07-01

    Full Text Available Abstract Background Classical swine fever virus (CSFV is the member of the genus Pestivirus under the family Flaviviridae. The 5' untranslated region (UTR of CSFV contains the IRES, which is a highly structured element that recruits the translation machinery. The 3' UTR is usually the recognition site of the viral replicase to initiate minus-strand RNA synthesis. Adenosine-uridine rich elements (ARE are instability determinants present in the 3' UTR of short-lived mRNAs. However, the presence of AREs in the 3' UTR of CSFV conserved in all known strains has never been reported. This study inspects a possible role of the ARE in the 3' UTR of CSFV. Results Using RNA pull-down and LC/MS/MS assays, this study identified at least 32 possible host factors derived from the cytoplasmic extracts of PK-15 cells that bind to the CSFV 3' UTR, one of which is HuR. HuR is known to bind the AREs and protect the mRNA from degradation. Using recombinant GST-HuR, this study demonstrates that HuR binds to the ARE present in the 3' UTR of CSFV in vitro and that the binding ability is conserved in strains irrespective of virulence. Conclusions This study identified one of the CSFV 3' UTR binding proteins HuR is specifically binding to in the ARE region.

  6. Classical Swine Fever-An Updated Review.

    Science.gov (United States)

    Blome, Sandra; Staubach, Christoph; Henke, Julia; Carlson, Jolene; Beer, Martin

    2017-04-21

    Classical swine fever (CSF) remains one of the most important transboundary viral diseases of swine worldwide. The causative agent is CSF virus, a small, enveloped RNA virus of the genus Pestivirus. Based on partial sequences, three genotypes can be distinguished that do not, however, directly correlate with virulence. Depending on both virus and host factors, a wide range of clinical syndromes can be observed and thus, laboratory confirmation is mandatory. To this means, both direct and indirect methods are utilized with an increasing degree of commercialization. Both infections in domestic pigs and wild boar are of great relevance; and wild boars are a reservoir host transmitting the virus sporadically also to pig farms. Control strategies for epidemic outbreaks in free countries are mainly based on classical intervention measures; i.e., quarantine and strict culling of affected herds. In these countries, vaccination is only an emergency option. However, live vaccines are used for controlling the disease in endemically infected regions in Asia, Eastern Europe, the Americas, and some African countries. Here, we will provide a concise, updated review on virus properties, clinical signs and pathology, epidemiology, pathogenesis and immune responses, diagnosis and vaccination possibilities.

  7. Multiple linear B-cell epitopes of classical swine fever virus glycoprotein E2 expressed in E.coli as multiple epitope vaccine induces a protective immune response

    Directory of Open Access Journals (Sweden)

    Wei Jian-Chao

    2011-07-01

    Full Text Available Abstract Classical swine fever is a highly contagious disease of swine caused by classical swine fever virus, an OIE list A pathogen. Epitope-based vaccines is one of the current focuses in the development of new vaccines against classical swine fever virus (CSFV. Two B-cell linear epitopes rE2-ba from the E2 glycoprotein of CSFV, rE2-a (CFRREKPFPHRMDCVTTTVENED, aa844-865 and rE2-b (CKEDYRYAISSTNEIGLLGAGGLT, aa693-716, were constructed and heterologously expressed in Escherichia coli as multiple epitope vaccine. Fifteen 6-week-old specified-pathogen-free (SPF piglets were intramuscularly immunized with epitopes twice at 2-week intervals. All epitope-vaccinated pigs could mount an anamnestic response after booster vaccination with neutralizing antibody titers ranging from 1:16 to 1:256. At this time, the pigs were subjected to challenge infection with a dose of 1 × 106 TCID50 virulent CSFV strain. After challenge infection, all of the rE2-ba-immunized pigs were alive and without symptoms or signs of CSF. In contrast, the control pigs continuously exhibited signs of CSF and had to be euthanized because of severe clinical symptoms at 5 days post challenge infection. The data from in vivo experiments shown that the multiple epitope rE2-ba shown a greater protection (similar to that of HCLV vaccine than that of mono-epitope peptide(rE2-a or rE2-b. Therefore, The results demonstrated that this multiple epitope peptide expressed in a prokaryotic system can be used as a potential DIVA (differentiating infected from vaccinated animals vaccine. The E.coli-expressed E2 multiple B-cell linear epitopes retains correct immunogenicity and is able to induce a protective immune response against CSFV infection.

  8. Tissue expression of Toll-like receptors 2, 3, 4 and 7 in swine in response to the Shimen strain of classical swine fever virus

    Science.gov (United States)

    Cao, Zhi; Zheng, Minping; Lv, Huifang; Guo, Kangkang; Zhang, Yanming

    2018-01-01

    The Toll-like receptors (TLRs) of the innate immune system provide the host with the ability to detect and respond to viral infections. The present study aimed to investigate the mRNA and protein expression levels of TLR2, 3, 4 and 7 in porcine tissues upon infection with the highly virulent Shimen strain of classical swine fever virus (CSFV). Reverse transcription-quantitative polymerase chain reaction was used to detect the mRNA expression levels of CSFV and TLR, whereas western blotting was used to detect the expression levels of TLR proteins. In addition, tissues underwent histological examination and immunohistochemistry to reveal the histopathological alterations associated with highly virulent CSFV infection and to detect TLR antigens. Furthermore, porcine monocyte-derived macrophages (pMDMs) were prestimulated with peptidoglycan from Staphylococcus aureus (PGN-SA), polyinosinic-polycytidylic acid [poly (I:C)], lipopolysaccharide from Escherichia coli 055:B5 (LPS-B5) or imiquimod (R837) in order to analyze the association between TLR expression and CSFV replication. Following stimulation for 12 h (with TLR-specific ligands), cells were infected with CSFV Shimen strain. The results revealed that the expression levels of TLR2 and TLR4 were increased in the lung and kidney, but were decreased in the spleen and lymph nodes in response to CSFV. TLR3 was strongly expressed in the heart and slightly upregulated in the spleen in response to CSFV Shimen strain infection, and TLR7 was increased in all examined tissues in the presence of CSFV. Furthermore, R837 and LPS-B5 exerted inhibitory effects on CSFV replication in pMDMs, whereas PGN-SA and poly(I:C) had no significant effect. These findings highlight the potential role of TLR expression in the context of CSFV infection. PMID:29568891

  9. Economic Analysis of Classical Swine Fever Surveillance in The Netherlands

    NARCIS (Netherlands)

    Guo, X.; Claassen, G.D.H.; Oude Lansink, A.G.J.M.; Loeffen, W.; Saatkamp, H.W.

    2016-01-01

    Classical swine fever (CSF) is a highly contagious pig disease that causes economic losses and impaired animal welfare. Improving the surveillance system for CSF can help to ensure early detection of the virus, thereby providing a better initial situation for controlling the disease. Economic

  10. Humoral and cellular immune response in mice induced by the classical swine fever virus E2 protein fused to the porcine CD154 antigen.

    Science.gov (United States)

    Sordo, Yusmel; Suárez, Marisela; Caraballo, Rosalina; Sardina, Talía; Brown, Emma; Duarte, Carlos; Lugo, Joanna; Gil, Lázaro; Perez, Danny; Oliva, Ayme; Vargas, Milagros; Santana, Elaine; Valdés, Rodolfo; Rodríguez, María Pilar

    2018-03-01

    The development of subunit vaccines against classical swine fever is a desirable goal, because it allows discrimination between vaccinated and infected animals. In this study, humoral and cellular immune response elicited in inbred BALB/c mice by immunization with a recombinant classical swine fever virus (CSFV) E2 protein fused to porcine CD154 antigen (E2CD154) was assessed. This model was used as a predictor of immune response in swine. Mice were immunized with E2CD154 emulsified in Montanide ISA50V2 or dissolved in saline on days 1 and 21. Another group received E2His antigen, without CD154, in the same adjuvant. Montanide ISA50V2 or saline served as negative controls for each experimental group. Animals immunized with 12.5 and 2.5 μg/dose of E2CD154 developed the highest titers (>1:2000) of CSFV neutralizing antibodies. Moreover, CSFV specific splenocyte gamma-interferon production, measured after seven and twenty-eight days of immunization, was significantly higher in mice immunized with 12.5 μg of E2CD154. As a conclusion, E2CD154 emulsified in Montanide ISA50 V2 was able to induce a potent humoral and an early cellular immune response in inbred BALB/c mice. Therefore, this immunogen might be an appropriate candidate to elicit immune response in swine, control CSF disease and to eliminate CSFV in swine. Copyright © 2018 International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

  11. African Swine Fever Virus Georgia 2007 with a Deletion of Virulence-Associated Gene 9GL (B119L), when Administered at Low Doses, Leads to Virus Attenuation in Swine and Induces an Effective Protection against Homologous Challenge.

    Science.gov (United States)

    O'Donnell, Vivian; Holinka, Lauren G; Krug, Peter W; Gladue, Douglas P; Carlson, Jolene; Sanford, Brenton; Alfano, Marialexia; Kramer, Edward; Lu, Zhiqiang; Arzt, Jonathan; Reese, Bo; Carrillo, Consuelo; Risatti, Guillermo R; Borca, Manuel V

    2015-08-01

    African swine fever virus (ASFV) is the etiological agent of an often lethal disease of domestic pigs. Disease control strategies have been hampered by the unavailability of vaccines against ASFV. Since its introduction in the Republic of Georgia, a highly virulent virus, ASFV Georgia 2007 (ASFV-G), has caused an epizootic that spread rapidly into Eastern European countries. Currently no vaccines are available or under development to control ASFV-G. In the past, genetically modified ASFVs harboring deletions of virulence-associated genes have proven attenuated in swine, inducing protective immunity against challenge with homologous parental viruses. Deletion of the gene 9GL (open reading frame [ORF] B119L) in highly virulent ASFV Malawi-Lil-20/1 produced an attenuated phenotype even when administered to pigs at 10(6) 50% hemadsorption doses (HAD50). Here we report the construction of a genetically modified ASFV-G strain (ASFV-G-Δ9GLv) harboring a deletion of the 9GL (B119L) gene. Like Malawi-Lil-20/1-Δ9GL, ASFV-G-Δ9GL showed limited replication in primary swine macrophages. However, intramuscular inoculation of swine with 10(4) HAD50 of ASFV-G-Δ9GL produced a virulent phenotype that, unlike Malawi-Lil-20/1-Δ9GL, induced a lethal disease in swine like parental ASFV-G. Interestingly, lower doses (10(2) to 10(3) HAD50) of ASFV-G-Δ9GL did not induce a virulent phenotype in swine and when challenged protected pigs against disease. A dose of 10(2) HAD50 of ASFV-G-Δ9GLv conferred partial protection when pigs were challenged at either 21 or 28 days postinfection (dpi). An ASFV-G-Δ9GL HAD50 of 10(3) conferred partial and complete protection at 21 and 28 dpi, respectively. The information provided here adds to our recent report on the first attempts toward experimental vaccines against ASFV-G. The main problem for controlling ASF is the lack of vaccines. Studies on ASFV virulence lead to the production of genetically modified attenuated viruses that induce protection

  12. Sodium phenylbutyrate abrogates African swine fever virus replication by disrupting the virus-induced hypoacetylation status of histone H3K9/K14.

    Science.gov (United States)

    Frouco, Gonçalo; Freitas, Ferdinando B; Martins, Carlos; Ferreira, Fernando

    2017-10-15

    African swine fever virus (ASFV) causes a highly lethal disease in swine for which neither a vaccine nor treatment are available. Recently, a new class of drugs that inhibit histone deacetylases enzymes (HDACs) has received an increasing interest as antiviral agents. Considering studies by others showing that valproic acid, an HDAC inhibitor (HDACi), blocks the replication of enveloped viruses and that ASFV regulates the epigenetic status of the host cell by promoting heterochromatinization and recruitment of class I HDACs to viral cytoplasmic factories, the antiviral activity of four HDACi against ASFV was evaluated in this study. Results showed that the sodium phenylbutyrate fully abrogates the ASFV replication, whereas the valproic acid leads to a significant reduction of viral progeny at 48h post-infection (-73.9%, p=0.046), as the two pan-HDAC inhibitors tested (Trichostatin A: -82.2%, p=0.043; Vorinostat: 73.9%, p=0.043). Further evaluation showed that protective effects of NaPB are dose-dependent, interfering with the expression of late viral genes and reversing the ASFV-induced histone H3 lysine 9 and 14 (H3K9K14) hypoacetylation status, compatible to an open chromatin state and possibly enabling the expression of host genes non-beneficial to infection progression. Additionally, a synergic antiviral effect was detected when NaPB is combined with an ASFV-topoisomerase II poison (Enrofloxacin). Altogether, our results strongly suggest that cellular HDACs are involved in the establishment of ASFV infection and emphasize that further in vivo studies are needed to better understand the antiviral activity of HDAC inhibitors. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Early pathogenesis of classical swine fever virus (CSFV) strains in Danish pigs

    DEFF Research Database (Denmark)

    Lohse, Louise; Nielsen, Jens; Uttenthal, Åse

    2012-01-01

    between strains, however, lymphoid atrophy and growth retardation represented a consistent finding for all 4 strains. Virus distribution, viral load and in particular virus persistence differed, but supported present practice that recommends lymphoid tissue, most optimal tonsil and lymph nodes, as target...... material to be applied for early laboratory diagnosis. The present study demonstrated constraints associated with early detection of infections with CSFV strains of low virulence. Since neither clinical symptoms nor pathological lesions observed with these strains constituted characteristic signs of CSF...

  14. Transmission of African swine fever virus from infected pigs by direct contact and aerosol routes

    DEFF Research Database (Denmark)

    Olesen, Ann Sofie; Lohse, Louise; Boklund, Anette

    2017-01-01

    from Poland (designated here POL/2015/Podlaskie/Lindholm). In both studies, pigs were inoculated intranasally with the virus and contact pigs were exposed to the experimentally infected pigs, either directly (contact within and between pens) or by air. Pigs exposed to the virus by intranasal...... and occasionally infectious virus was found in nasal-, oral-, and rectal swabs obtained from the pigs, and ASFV DNA was detected in air samples. No anti-ASFV antibodies were detected in sera.In conclusion, the study shows that the currently circulating strain of ASFV can be efficiently transmitted via direct...... contact and by aerosols. Also, the results provide quantitative transmission parameters and knowledge of infection stages in pigs infected with this ASFV....

  15. Experimental Infection of Ornithodoros erraticus sensu stricto with Two Portuguese African Swine Fever Virus Strains. Study of Factors Involved in the Dynamics of Infection in Ticks.

    Directory of Open Access Journals (Sweden)

    Rita Ribeiro

    Full Text Available African swine fever (ASF is a frequently devastating hemorrhagic disease of domestic pigs and wild boar and Ornithodoros erraticus sensu stricto argasid ticks are the only biological vectors of African swine fever virus (ASFV known to occur in Europe. Recently this disease emerged in Eastern Europe and Russian Federation, showing a huge potential for a rapid spread between countries. There is some risk of re-emergence of ASF in the countries where these ticks exist, that can contribute for the persistence of infection and compromise control measures. In this study we aimed to identify factors that determine the probability of infection and its dynamics in the tick vector Ornithodoros erraticus sensu stricto, with two Portuguese strains of ASFV. Our results suggest that these ticks have a high likelihood of excreting the two haemadsorbing ASF viruses of different host origins and that, in field surveys, the analysis of adults and 5th nymphal stage can provide the best chance of detecting virus infection. The results also indicate that infection of pigs with highly virulent ASF viruses will promote higher rates of infection and a higher likelihood for virus excretion by ticks. Nevertheless, there is also a risk, although lower, that ticks can become infected on pigs that have overcome the acute phase of infection, which was simulated in our study by membrane feeding ticks with low titres of virus. We believe these results can be valuable in designing and interpreting the results of ASF control programmes, and future work can also be undertaken as our dataset is released under open access, to perform studies in risk assessment for ASFV persistence in a region where O. erraticus sensu stricto ticks are present.

  16. Rab1A is required for assembly of classical swine fever virus particle.

    Science.gov (United States)

    Lin, Jihui; Wang, Chengbao; Liang, Wulong; Zhang, Jing; Zhang, Longxiang; Lv, Huifang; Dong, Wang; Zhang, Yanming

    2018-01-15

    Rab1A belongs to the small Rab GTPase family and is involved in the lifecycle of numerous viruses. Here, knockdown of Rab1A inhibited CSFV growth. Further study revealed that Rab1A depletion decreased intracellular and extracellular CSFV titers, but did not affect intracellular virus genome copies and E2 protein expression within a virus lifecycle, which suggested that Rab1A is required for CSFV particle assembly rather than for genome replication or virion release. This was proofed by blocking the spread of virus using neutralizing antibodies, through which the negative effects of Rab1A knockdown on multi-cycle replication of CSFV were eliminated. Moreover, co-immunoprecipitation and confocal microscopy assays showed that Rab1A bound to CSFV NS5A protein, indicating that Rab1A and viral NS5A proteins may work cooperatively during CSFV particle assembly. In conclusion, this study demonstrated for the first time that Rab1A is required for CSFV particle assembly and binds to viral particle assembly-related NS5A protein. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Molecular epidemiology of current classical swine fever virus isolates of wild boar in Germany

    DEFF Research Database (Denmark)

    Leifer, I; Hoffmann, B; Höper, D

    2010-01-01

    to study virus spread and evolutionary history in German wild boar. For the first time, the results of our study clearly argue for the possibility of a long-term persistence of genotype 2.3 CSFV strains in affected regions at an almost undetectable level, even after long-term oral vaccination campaigns...

  18. [The present epidemiological status of African swine fever].

    Science.gov (United States)

    Hess, G

    1986-01-01

    At present, African swine fever (ASF) persists as an enzootic infection both on the African continent and in Europe (Portugal, Spain, and Sardinia). The recent outbreaks of ASF in Belgium and in the Netherlands have again demonstrated the threat of this disease to the swine population in Germany. The main reasons for this threat are the great tenacity of this virus and its stability in meat and meat products together with an immense tourism into these enzootic areas. Epizootiological peculiarities, such as virus replication in ticks and inapparent infections in wild boars are the reason why eradication of the disease has failed so far, especially when pigs are allowed to roam the countryside.

  19. Novel poly-uridine insertion in the 3'UTR and E2 amino acid substitutions in a low virulent classical swine fever virus.

    Science.gov (United States)

    Coronado, Liani; Liniger, Matthias; Muñoz-González, Sara; Postel, Alexander; Pérez, Lester Josue; Pérez-Simó, Marta; Perera, Carmen Laura; Frías-Lepoureau, Maria Teresa; Rosell, Rosa; Grundhoff, Adam; Indenbirken, Daniela; Alawi, Malik; Fischer, Nicole; Becher, Paul; Ruggli, Nicolas; Ganges, Llilianne

    2017-03-01

    In this study, we compared the virulence in weaner pigs of the Pinar del Rio isolate and the virulent Margarita strain. The latter caused the Cuban classical swine fever (CSF) outbreak of 1993. Our results showed that the Pinar del Rio virus isolated during an endemic phase is clearly of low virulence. We analysed the complete nucleotide sequence of the Pinar del Rio virus isolated after persistence in newborn piglets, as well as the genome sequence of the inoculum. The consensus genome sequence of the Pinar del Rio virus remained completely unchanged after 28days of persistent infection in swine. More importantly, a unique poly-uridine tract was discovered in the 3'UTR of the Pinar del Rio virus, which was not found in the Margarita virus or any other known CSFV sequences. Based on RNA secondary structure prediction, the poly-uridine tract results in a long single-stranded intervening sequence (SS) between the stem-loops I and II of the 3'UTR, without major changes in the stem- loop structures when compared to the Margarita virus. The possible implications of this novel insertion on persistence and attenuation remain to be investigated. In addition, comparison of the amino acid sequence of the viral proteins E rns , E1, E2 and p7 of the Margarita and Pinar del Rio viruses showed that all non-conservative amino acid substitutions acquired by the Pinar del Rio isolate clustered in E2, with two of them being located within the B/C domain. Immunisation and cross-neutralisation experiments in pigs and rabbits suggest differences between these two viruses, which may be attributable to the amino acid differences observed in E2. Altogether, these data provide fresh insights into viral molecular features which might be associated with the attenuation and adaptation of CSFV for persistence in the field. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Effect of specific amino acid substitutions in the putative fusion peptide of structural glycoprotein E2 on Classical Swine Fever Virus replication

    International Nuclear Information System (INIS)

    Fernández-Sainz, I.J.; Largo, E.; Gladue, D.P.; Fletcher, P.; O’Donnell, V.; Holinka, L.G.; Carey, L.B.; Lu, X.; Nieva, J.L.; Borca, M.V.

    2014-01-01

    E2, along with E rns and E1, is an envelope glycoprotein of Classical Swine Fever Virus (CSFV). E2 is involved in several virus functions: cell attachment, host range susceptibility and virulence in natural hosts. Here we evaluate the role of a specific E2 region, 818 CPIGWTGVIEC 828 , containing a putative fusion peptide (FP) sequence. Reverse genetics utilizing a full-length infectious clone of the highly virulent CSFV strain Brescia (BICv) was used to evaluate how individual amino acid substitutions within this region of E2 may affect replication of BICv. A synthetic peptide representing the complete E2 FP amino acid sequence adopted a β-type extended conformation in membrane mimetics, penetrated into model membranes, and perturbed lipid bilayer integrity in vitro. Similar peptides harboring amino acid substitutions adopted comparable conformations but exhibited different membrane activities. Therefore, a preliminary characterization of the putative FP 818 CPIGWTGVIEC 828 indicates a membrane fusion activity and a critical role in virus replication. - Highlights: • A putative fusion peptide (FP) region in CSFV E2 protein was shown to be critical for virus growth. • Synthetic FPs were shown to efficiently penetrate into lipid membranes using an in vitro model. • Individual residues in the FP affecting virus replication were identified by reverse genetics. • The same FP residues are also responsible for mediating membrane fusion

  1. Effect of specific amino acid substitutions in the putative fusion peptide of structural glycoprotein E2 on Classical Swine Fever Virus replication

    Energy Technology Data Exchange (ETDEWEB)

    Fernández-Sainz, I.J. [Plum Island Animal Disease Center, ARS, USDA (United States); Largo, E. [Biophysics Unit (CSIC-UPV/EHU), Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), P.O. Box 644, 48080 Bilbao (Spain); Gladue, D.P.; Fletcher, P. [Plum Island Animal Disease Center, ARS, USDA (United States); O’Donnell, V. [Plum Island Animal Disease Center, ARS, USDA (United States); Plum Island Animal Disease Center, DHS, Greenport, NY 11944 (United States); Holinka, L.G. [Plum Island Animal Disease Center, ARS, USDA (United States); Carey, L.B. [Department of Experimental and Health Sciences, Universitat Pompeu Fabra (UPF), E-08003 Barcelona (Spain); Lu, X. [Plum Island Animal Disease Center, DHS, Greenport, NY 11944 (United States); Nieva, J.L. [Biophysics Unit (CSIC-UPV/EHU), Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), P.O. Box 644, 48080 Bilbao (Spain); Borca, M.V., E-mail: manuel.borca@ars.usda.gov [Plum Island Animal Disease Center, ARS, USDA (United States)

    2014-05-15

    E2, along with E{sup rns} and E1, is an envelope glycoprotein of Classical Swine Fever Virus (CSFV). E2 is involved in several virus functions: cell attachment, host range susceptibility and virulence in natural hosts. Here we evaluate the role of a specific E2 region, {sup 818}CPIGWTGVIEC{sup 828}, containing a putative fusion peptide (FP) sequence. Reverse genetics utilizing a full-length infectious clone of the highly virulent CSFV strain Brescia (BICv) was used to evaluate how individual amino acid substitutions within this region of E2 may affect replication of BICv. A synthetic peptide representing the complete E2 FP amino acid sequence adopted a β-type extended conformation in membrane mimetics, penetrated into model membranes, and perturbed lipid bilayer integrity in vitro. Similar peptides harboring amino acid substitutions adopted comparable conformations but exhibited different membrane activities. Therefore, a preliminary characterization of the putative FP {sup 818}CPIGWTGVIEC{sup 828} indicates a membrane fusion activity and a critical role in virus replication. - Highlights: • A putative fusion peptide (FP) region in CSFV E2 protein was shown to be critical for virus growth. • Synthetic FPs were shown to efficiently penetrate into lipid membranes using an in vitro model. • Individual residues in the FP affecting virus replication were identified by reverse genetics. • The same FP residues are also responsible for mediating membrane fusion.

  2. Genome Sequence of African Swine Fever Virus BA71, the Virulent Parental Strain of the Nonpathogenic and Tissue-Culture Adapted BA71V.

    Science.gov (United States)

    Rodríguez, Javier M; Moreno, Leticia Tais; Alejo, Alí; Lacasta, Anna; Rodríguez, Fernando; Salas, María L

    2015-01-01

    The strain BA71V has played a key role in African swine fever virus (ASFV) research. It was the first genome sequenced, and remains the only genome completely determined. A large part of the studies on the function of ASFV genes, viral transcription, replication, DNA repair and morphogenesis, has been performed using this model. This avirulent strain was obtained by adaptation to grow in Vero cells of the highly virulent BA71 strain. We report here the analysis of the genome sequence of BA71 in comparison with that of BA71V. They possess the smallest genomes for a virulent or an attenuated ASFV, and are essentially identical except for a relatively small number of changes. We discuss the possible contribution of these changes to virulence. Analysis of the BA71 sequence allowed us to identify new similarities among ASFV proteins, and with database proteins including two ASFV proteins that could function as a two-component signaling network.

  3. Next Generation Sequencing of Classical Swine Fever Virus and Border Disease virus cloned in Bacterial Artificial Chromosomes

    DEFF Research Database (Denmark)

    Fahnøe, Ulrik; Höper, Dirk; Beer, martin

    2012-01-01

    artificial chromosomes (BACs). From these BACs, RNA copies of the viral genomes can be transcribed in vitro and upon transfection of these RNAs into mammalian cells, autonomous replication of the viral genome occurs and infectious progeny can be rescued. However, we have observed that virus progeny can...

  4. The eukaryotic translation initiation factor 3 subunit E binds to classical swine fever virus NS5A and facilitates viral replication.

    Science.gov (United States)

    Liu, Xiaofeng; Wang, Xiaoyu; Wang, Qian; Luo, Mingyang; Guo, Huancheng; Gong, Wenjie; Tu, Changchun; Sun, Jinfu

    2018-02-01

    Classical swine fever virus (CSFV) NS5A protein is a multifunctional protein, playing critical roles in viral RNA replication, translation and assembly. To further explore its functions in viral replication, interaction of NS5A with host factors was assayed using a his-tag "pull down" assay coupled with shotgun LC-MS/MS. Host protein translation initiation factor 3 subunit E was identified as a binding partner of NS5A, and confirmed by co-immunoprecipitation and co-localization analysis. Overexpression of eIF3E markedly enhanced CSFV genomic replication, viral protein expression and production of progeny virus, and downregulation of eIF3E by siRNA significantly decreased viral proliferation in PK-15 cells. Luciferase reporter assay showed an enhancement of translational activity of the internal ribosome entry site of CSFV by eIF3E and a decrease in cellular translation by NS5A. These data indicate that eIF3E plays an important role in CSFV replication, thereby identifying it as a potential target for inhibition of the virus. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Characterisation of vaccine-induced, broadly cross-reactive IFN-γ secreting T cell responses that correlate with rapid protection against classical swine fever virus.

    Science.gov (United States)

    Graham, Simon P; Haines, Felicity J; Johns, Helen L; Sosan, Olubukola; La Rocca, S Anna; Lamp, Benjamin; Rümenapf, Till; Everett, Helen E; Crooke, Helen R

    2012-04-05

    Live attenuated C-strain classical swine fever viruses (CSFV) provide a rapid onset of protection, but the lack of a serological test that can differentiate vaccinated from infected animals limits their application in CSF outbreaks. Since immunity may precede antibody responses, we examined the kinetics and specificity of peripheral blood T cell responses from pigs vaccinated with a C-strain vaccine and challenged after five days with a genotypically divergent CSFV isolate. Vaccinated animals displayed virus-specific IFN-γ responses from day 3 post-challenge, whereas, unvaccinated challenge control animals failed to mount a detectable response. Both CD4(+) and cytotoxic CD8(+) T cells were identified as the cellular source of IFN-γ. IFN-γ responses showed extensive cross-reactivity when T cells were stimulated with CSFV isolates spanning the major genotypes. To determine the specificity of these responses, T cells were stimulated with recombinant CSFV proteins and a proteome-wide peptide library from a related virus, BVDV. Major cross-reactive peptides were mapped on the E2 and NS3 proteins. Finally, IFN-γ was shown to exert potent antiviral effects on CSFV in vitro. These data support the involvement of broadly cross-reactive T cell IFN-γ responses in the rapid protection conferred by the C-strain vaccine and this information should aid the development of the next generation of CSFV vaccines. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  6. Classical swine fever in India: current status and future perspective.

    Science.gov (United States)

    Singh, Vinod Kumar; Rajak, Kaushal Kishore; Kumar, Amit; Yadav, Sharad Kumar

    2018-05-04

    Classical swine fever (CSF) is a globally significant disease of swine caused by classical swine fever virus. The virus affects the wild boars and pigs of all age groups, leading to acute, chronic, late-onset or in-apparent course of the disease. The disease causes great economic loss to the piggery industry due to mortality, stunted growth, poor reproductive performance, and by impeding the international trade of pig and pig products. In India, CSF outbreaks are reported from most of the states wherever pig rearing is practiced and more frequently from northeast states. In spite of the highly devastating nature and frequent outbreaks, CSF remained underestimated and neglected for decades in India. The country requires rapid and sensitive diagnostic tests for an early detection of infection to limit the spread of the disease. Also, effective prophylactics are required to help in control and eradication of the disease for the development of the piggery industry. This review looks into the economic impact; epidemiology of CSF highlighting the temporal and spatial occurrence of outbreaks in the last two decades, circulation, and emergence of the virus genotypes in and around the country; and the constraints in the disease control, with the aim to update the knowledge of current status of the disease in India. The article also emphasizes the importance of the disease and the need to develop rapid specific diagnostics and effective measures to eradicate the disease.

  7. Rab5 Enhances Classical Swine Fever Virus Proliferation and Interacts with Viral NS4B Protein to Facilitate Formation of NS4B Related Complex

    Directory of Open Access Journals (Sweden)

    Jihui Lin

    2017-08-01

    Full Text Available Classical swine fever virus (CSFV is a fatal pig pestivirus and causes serious financial losses to the pig industry. CSFV NS4B protein is one of the most important viral replicase proteins. Rab5, a member of the small Rab GTPase family, is involved in infection and replication of numerous viruses including hepatitis C virus and dengue virus. Until now, the effects of Rab5 on the proliferation of CSFV are poorly defined. In the present study, we showed that Rab5 could enhance CSFV proliferation by utilizing lentivirus-mediated constitutive overexpression and eukaryotic plasmid transient overexpression approaches. On the other hand, lentivirus-mediated short hairpin RNA knockdown of Rab5 dramatically inhibited virus production. Co-immunoprecipitation, glutathione S-transferase pulldown and laser confocal microscopy assays further confirmed the interaction between Rab5 and CSFV NS4B protein. In addition, intracellular distribution of NS4B-Red presented many granular fluorescent signals (GFS in CSFV infected PK-15 cells. Inhibition of basal Rab5 function with Rab5 dominant negative mutant Rab5S34N resulted in disruption of the GFS. These results indicate that Rab5 plays a critical role in facilitating the formation of the NS4B related complexes. Furthermore, it was observed that NS4B co-localized with viral NS3 and NS5A proteins in the cytoplasm, suggesting that NS3 and NS5A might be components of the NS4B related complex. Taken together, these results demonstrate that Rab5 positively modulates CSFV propagation and interacts with NS4B protein to facilitate the NS4B related complexes formation.

  8. Simulating the epidemiological and economic effects of an African swine fever epidemic in industrialized swine populations

    DEFF Research Database (Denmark)

    Hisham Beshara Halasa, Tariq; Bøtner, Anette; Mortensen, Sten

    2016-01-01

    to simulate the spread of ASF virus between domestic swine herds exemplified by the Danish swine population. ASF was simulated to spread via animal movement, low- or medium-risk contacts and local spread. Each epidemic was initiated in a randomly selected herd – either in a nucleus herd, a sow herd......African swine fever (ASF) is a notifiable infectious disease with a considerable impact on animal health and is currently one of the most important emerging diseases of domestic pigs. ASF was introduced into Georgia in 2007 and subsequently spread to the Russian Federation and several Eastern...... European countries. Consequently, there is a non-negligible risk of ASF spread towards Western Europe. Therefore it is important to develop tools to improve our understanding of the spread and control of ASF for contingency planning. A stochastic and dynamic spatial spread model (DTU-DADS) was adjusted...

  9. Predominance of genotype 1.1 and emergence of genotype 2.2 classical swine fever viruses in north-eastern region of India.

    Science.gov (United States)

    Roychoudhury, P; Sarma, D K; Rajkhowa, S; Munir, M; Kuchipudi, S V

    2014-08-01

    Classical swine fever (CSF) is a highly contagious and the most important disease of pigs worldwide.CSF is enzootic in pig herds in India and continues to cause huge economic losses to pig farmers. Nearly 40% of the total pig population of India is present in the north-eastern (NE) states where pig husbandry plays an important role in the socio-economic development. Pigs reared in the backyards are the only source of livelihood for a majority of poor tribal population in the region. Hardly any CSF vaccination is currently being undertaken in the unorganized pig farming in the NE region due to economic reasons and vaccine unavailability. A thorough understanding of the current epidemiological status of CSF is essential for the effective control of the disease in the NE region. Hence, we carried out molecular characterization of CSFV isolates from field outbreaks during 2011-2012 in the entire north-eastern region of India to establish the genetic groups of prevalent CSF viruses in the region. A total of 17 CSFV isolates obtained from different parts of the NE region were characterized by comparing the sequences of three partial genomic regions of the virus, that is 150 nt of 5' UTR, 190 nt of E2 and 409 nt of NS5B. Of the 17 CSFV isolates, 15 isolates belonged to 1.1 (88.2%) and two isolates (11.8%) belonged to 2.2 subgenogroup. The genogroup 2.2 CSFV were associated with outbreaks in Arunachal Pradesh that shares international borders with Bhutan, Myanmar and China. Genogroup 2.2 CSFV isolated in the present study shared high level of sequence similarity with 2.2 viruses form China, raising the possibility of virus incursion from this region. In summary, we found a continued predominance of 1.1 subgroup and an emergence of 2.2 subgroup CSFV in NE region of India. © 2014 Blackwell Verlag GmbH.

  10. A serological survey on classical swine fever (CSF), Aujeszky's disease (AD) and porcine reproductive and respiratory syndrome (PRRS) virus infections in French wild boars from 1991 to 1998.

    Science.gov (United States)

    Albina, E; Mesplède, A; Chenut, G; Le Potier, M F; Bourbao, G; Le Gal, S; Leforban, Y

    2000-11-15

    In early 1992, a CSF epizootic was clinically recognised in a wild boar population of approximately 1300 animals within an area of 250km(2) located in the east of France. In order to check the CSF situation in wild boars outside this area, a serological survey was carried out in the rest of France, for 8 consecutive years (1991-1998). This paper reports on the results obtained during this survey which included wild boars shot during the hunting period but also boars reared within fences. Around 1000-2700 sera a year were tested for the presence of antibodies to classical swine fever virus (CSFV) and also to Aujeszky's disease virus (ADV). Out of 12025 sera tested over the whole period, 80 wild boars were found positive for CSF antibodies. Sixty of them were collected on wild boars shot during the years 1992-1994 in the epizootic area located in east of France and 10 were collected in Corsica during the years 1994-1996. The last four positive samples were single reactors coming from areas or farms, which were thereafter confirmed to be serologically negative. These results together with the fact that no disease has been reported so far illustrate that the French wild boar population is probably not concerned by CSF infection (excepted in the east of France where the disease has now become enzootic). Two hundred and forty nine sera were initially detected as CSF positive but confirmed secondarily as positive for border disease (BD) antibodies. This finding shows that wild boars are also susceptible to infection by ruminant pestiviruses. Four hundred and twenty three wild boars have been found positive for ADV antibodies. In addition, from 1993 to 1995, 909 samples were tested for the presence of antibodies to porcine reproductive and respiratory syndrome virus (PRRSV). Thirty three of them were positive. The results on AD and PRRS antibody detection show that wild boars may constitute a reservoir for various infectious diseases of pigs.

  11. Quantitative risk assessment for the introduction of African swine fever virus into the European Union by legal import of live pigs.

    Science.gov (United States)

    Mur, L; Martínez-López, B; Martínez-Avilés, M; Costard, S; Wieland, B; Pfeiffer, D U; Sánchez-Vizcaíno, J M

    2012-04-01

    The recent incursion and spread of African swine fever virus (ASFV) in the Russian Federation and Caucasus region, close to European Union (EU) borders, have increased the concerns regarding the probability of ASFV introduction into the EU. There are many potential routes of ASFV entry into EU, but here we specifically aimed to assess the probability of ASFV introduction by legal trade of pigs, which historically has been one of the most important ways of exotic diseases introduction into the EU. A stochastic model was used to estimate the monthly probability of ASFV introduction for each country of the EU. Results of this model suggest an annual probability for ASFV introduction in the whole EU by this way of 5.22*10(-3) , which approximately corresponds with one outbreak in 192years. The risk of ASFV introduction via live pigs was highest in Poland (69%), particularly during the months of November and December. As expected, Russian Federation is the country that most contributes to this risk, representing 68% of the overall annual risk. Methods and results presented here may be useful for informing risk-based surveillance and control programmes and, ultimately, for prevention and control of potential ASFV incursions into the EU. © 2011 Blackwell Verlag GmbH.

  12. Cellular Hsp27 interacts with classical swine fever virus NS5A protein and negatively regulates viral replication by the NF-κB signaling pathway.

    Science.gov (United States)

    Ling, Shifeng; Luo, Mingyang; Jiang, Shengnan; Liu, Jiayu; Ding, Chunying; Zhang, Qinghuan; Guo, Huancheng; Gong, Wenjie; Tu, Changchun; Sun, Jinfu

    2018-05-01

    Classical swine fever virus (CSFV) nonstructural protein NS5A is a multifunctional protein functioning in regulation of viral genome replication, protein translation and assembly by interaction with viral or host proteins. Here, heat shock protein 27 (Hsp27) has been identified as a novel binding partner of NS5A by using His tag "pull down" coupled with shotgun LC-MS/MS, with interaction of both proteins further confirmed by co-immunoprecipitation and laser confocal assays. In PK-15 cells, silencing of Hsp27 expression by siRNA enhanced CSFV replication, and upregulation of Hsp27 inhibited viral proliferation. Additionally, we have shown that overexpression of Hsp27 increased NF-κB signaling induced by TNFα. Blocking NF-κB signaling in PK-15 cells overexpressing Hsp27 by ammonium pyrrolidinedithiocarbamate (PDTC) eliminated the inhibition of CSFV replication by Hsp27. These findings clearly demonstrate that the inhibition of CSFV replication by Hsp27 is mediated via the NF-κB signaling pathway. Copyright © 2018 Elsevier Inc. All rights reserved.

  13. Detection of African Swine Fever Virus DNA in Blood Samples Stored on FTA Cards from Asymptomatic Pigs in Mbeya Region, Tanzania

    DEFF Research Database (Denmark)

    Braae, U. C.; Johansen, M. V.; Ngowi, H. A.

    2015-01-01

    The aim of the study was to assess whether blood samples collected onto FTA® cards could be used in combination with real-time PCR for the detection of African swine fever virus (ASFV) DNA in samples from resource-poor settings under the assumption that asymptomatically (sub-clinically) infected...... pigs may be present. Blood samples were collected from clinically healthy pigs from Mbeya Region, Tanzania. The blood samples were stored on FTA® cards and analysed by real-time PCR assays in duplicate; three pigs had high levels of viral DNA (Ct values of 27-29), and three pigs had a low level....../1) or a non-pathogenic (OURT T88/3) isolate of ASFV were collected, stored on FTA® cards and analysed in the same way. The blood from pigs infected with the OURT T88/1 isolate showed high levels of viral DNA (Ct 22-33), whereas infection with non-pathogenic OURT T88/3 isolate resulted in only low levels...

  14. Detection of African swine fever virus DNA in blood samples stored on FTA cards from asymptomatic pigs in Mbeya region, Tanzania.

    Science.gov (United States)

    Braae, U C; Johansen, M V; Ngowi, H A; Rasmussen, T B; Nielsen, J; Uttenthal, Å

    2015-02-01

    The aim of the study was to assess whether blood samples collected onto FTA(®) cards could be used in combination with real-time PCR for the detection of African swine fever virus (ASFV) DNA in samples from resource-poor settings under the assumption that asymptomatically (sub-clinically) infected pigs may be present. Blood samples were collected from clinically healthy pigs from Mbeya Region, Tanzania. The blood samples were stored on FTA(®) cards and analysed by real-time PCR assays in duplicate; three pigs had high levels of viral DNA (Ct values of 27-29), and three pigs had a low level of viral DNA (Ct 36-45). Four pigs were positive in one of the duplicate samples only, but clear products of the expected size were obtained when the reactions were analysed by gel electrophoresis. For comparison, blood samples from pigs experimentally infected with either a pathogenic (OURT T88/1) or a non-pathogenic (OURT T88/3) isolate of ASFV were collected, stored on FTA(®) cards and analysed in the same way. The blood from pigs infected with the OURT T88/1 isolate showed high levels of viral DNA (Ct 22-33), whereas infection with non-pathogenic OURT T88/3 isolate resulted in only low levels of viral DNA (Ct 39) in samples collected at 10-14 days after inoculation. © 2013 Blackwell Verlag GmbH.

  15. Genetic variation of classical swine fever virus based on palindromic nucleotide substitutions, a genetic marker in the 5' untranslated region of RNA

    Directory of Open Access Journals (Sweden)

    Massimo Giangaspero

    2008-06-01

    Full Text Available Forty-three strains of classical swine fever (hog cholera virus (CSFV from outbreaks in pigs in Europe, Asia and America, two strains from commercial CSFV modified live vaccines and a strain isolated from a diseased lamb from Spain were subjected to analyses of nucleotide sequence variations in the 5’ terminal region of the genome. These isolates were divided into three clusters, namely: CSFV-1, CSFV-2, and CSFV-3, based on palindromic nucleotide substitutions in the 5’ untranslated region (UTR. The homology degree, according to nucleotide base pairing variation in the secondary palindromic structure of the three variable loci V1, V2 and V3, was 60% in the CSFV species, with a mean divergence value of 6.19 base pairs (bp. relatedness within genotypes ranged from 71.11% to 100%, with mean divergence values from 5.5 to 0.73 base pairs. Subgenotypes showed a divergence ranging from 1 to 9 base pairs within the genotype. Genotype CSFV-1 revealed 15 base pair combinations with 13 divergent base pairs, resulting in 4 subgenotypes with 6 variants in subgenotype CSFV-1.1, including the reference strain Brescia and 6 variants in subgenotype CSFV-1.2, including the Alfort reference strain. Subgenotypes CSFV-1.3 and CSFV-1.4 comprised one and two variants, respectively. Genotype CSFV-2 was represented by the Spanish ovine isolate 5440/99 and the genotype CSFV-3 included the Japanese strains Okinawa/86 and Kanagawa/74. CSFV genotypes revealed a strong relationship with Border disease virus strains, showing relatively low divergence values when compared to other pestivirus species. Evaluation of nucleotide base pair divergence among genotypes and expression of evolutionary changes in the CSFV species led to the construction of a phylogenetic tree based on secondary structure.

  16. DNA-Binding Properties of African Swine Fever Virus pA104R, a Histone-Like Protein Involved in Viral Replication and Transcription.

    Science.gov (United States)

    Frouco, Gonçalo; Freitas, Ferdinando B; Coelho, João; Leitão, Alexandre; Martins, Carlos; Ferreira, Fernando

    2017-06-15

    African swine fever virus (ASFV) codes for a putative histone-like protein (pA104R) with extensive sequence homology to bacterial proteins that are implicated in genome replication and packaging. Functional characterization of purified recombinant pA104R revealed that it binds to single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA) over a wide range of temperatures, pH values, and salt concentrations and in an ATP-independent manner, with an estimated binding site size of about 14 to 16 nucleotides. Using site-directed mutagenesis, the arginine located in pA104R's DNA-binding domain, at position 69, was found to be relevant for efficient DNA-binding activity. Together, pA104R and ASFV topoisomerase II (pP1192R) display DNA-supercoiling activity, although none of the proteins by themselves do, indicating that the two cooperate in this process. In ASFV-infected cells, A104R transcripts were detected from 2 h postinfection (hpi) onward, reaching a maximum concentration around 16 hpi. pA104R was detected from 12 hpi onward, localizing with viral DNA replication sites and being found exclusively in the Triton-insoluble fraction. Small interfering RNA (siRNA) knockdown experiments revealed that pA104R plays a critical role in viral DNA replication and gene expression, with transfected cells showing lower viral progeny numbers (up to a reduction of 82.0%), lower copy numbers of viral genomes (-78.3%), and reduced transcription of a late viral gene (-47.6%). Taken together, our results strongly suggest that pA104R participates in the modulation of viral DNA topology, probably being involved in viral DNA replication, transcription, and packaging, emphasizing that ASFV mutants lacking the A104R gene could be used as a strategy to develop a vaccine against ASFV. IMPORTANCE Recently reintroduced in Europe, African swine fever virus (ASFV) causes a fatal disease in domestic pigs, causing high economic losses in affected countries, as no vaccine or treatment is currently

  17. Diagnostic specificity of the African swine fever virus antibody detection enzyme-linked immunosorbent assay in feral and domestic pigs in the United States.

    Science.gov (United States)

    Bergeron, H C; Glas, P S; Schumann, K R

    2017-12-01

    African swine fever (ASF) is a highly contagious haemorrhagic disease of pigs that has the potential to cause mortality nearing 100% in naïve animals. While an outbreak of ASF in the United States' pig population (domestic and feral) has never been reported, an introduction of the disease has the potential to cause devastation to the pork industry and food security. During the recovery phase of an outbreak, an antibody detection diagnostic assay would be required to prove freedom of disease within the previously infected zone and eventually nationwide. Animals surviving an ASF infection would be considered carriers and could be identified through the persistence of ASF viral antibodies. These antibodies would demonstrate exposure to the disease and not vaccination, as there is no ASF vaccine available. A well-established commercial enzyme-linked immunosorbent assay (ELISA) detects antibodies against ASF virus (ASFV), but the diagnostic specificity of the assay had not been determined using serum samples from the pig population of the United States. This study describes an evaluation of the World Organization for Animal Health (OIE)-recommended Ingezim PPA COMPAC ELISA using a comprehensive cohort (n = 1791) of samples collected in the United States. The diagnostic specificity of the assay was determined to be 99.4% (95% confidence interval (CI): [98.9, 99.7]). The result of this study fills a gap in understanding the performance of the Ingezim PPA COMPAC ELISA in the ASF naïve pig population of the United States. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  18. Classical swine fever virus detection: results of a real-time reverse transcription polymerase chain reaction ring trial conducted in the framework of the European network of excellence for epizootic disease diagnosis and control

    DEFF Research Database (Denmark)

    Hoffmann, Bernd; Blome, Sandra; Bonilauri, Paolo

    2011-01-01

    and specificity values. Nevertheless, some in-house systems had unspecific reactions or suboptimal sensitivity with only a single CSFV genotype. Follow-up actions involved either improvement of suboptimal assays or replacement of specific laboratory assays with the FLI protocol, with or without modifications......The current study reports on a real-time reverse transcription polymerase chain reaction (real-time RT-PCR) ring trial for the detection of Classical swine fever virus (CSFV) genomic RNA undertaken by 10 European laboratories. All laboratories were asked to use their routine in-house real-time RT...

  19. Obtaining classical swine fever virus E2 recombinant protein and DNA-vaccine on the basis of one subunit

    International Nuclear Information System (INIS)

    Deryabin, O.; Deryabina, O.; Verbitskiy, P.; Kordyum, V.

    2005-01-01

    Three forms of E2 recombinant protein were expressed in E. coli. Swine sera obtained against different forms of the recombinant protein were cross-studied with indirect ELISA. Using individual proteins as an antigen, only 15% of sera against other forms of protein reacted positively, while 100% of heterologous sera showed positive reaction with fused protein. Challenge experiments showed the existence of protective action only from the individual protein. Specificity and activity of sera obtained from the animals after control challenge was confirmed in a blocking variant of ELISA. Genetic construction used a eukaryotic vector that contained the E2 protein gene. Immunization of mice with the resulting DNA induced synthesis of specific antibodies, the titre of which increased considerably after additional single immunization with the E2 recombinant protein, expressed in E. coli. This demonstrated the effectiveness of animal priming by DNA vaccine, and the possibility of using the E2 recombinant protein in E. coli for booster vaccination. (author)

  20. Classical swine fever (CSF) marker vaccine - Trial I. Challenge studies in weaner pigs

    DEFF Research Database (Denmark)

    Uttenthal, Åse; Le Potier, M.F.; Romero, L.

    2001-01-01

    , -10 or -7, and subsequently challenged at day 0. The challenge virus was CSFV 277, originating from a recent outbreak of classical swine fever (CSF) in Germany. In all groups, only 5 out of 10 pigs were challenged; the remaining 5 pigs served as vaccinated contact controls. Also, three control groups...

  1. Variations in the severity of classical swine fever infections in Danish pigs - the clinical perspective

    DEFF Research Database (Denmark)

    Lohse, Louise; Uttenthal, Åse; Bruun, Camilla S.

    Aim The severity of classical swine fever virus (CSFV) infection is believed to be determined by different factors, including virulence of the specific strain as well as factors related to the host, e.g. age, genetic background and health status of the pig [1, 2]. In recent Danish experiments...

  2. Swine Influenza/Variant Influenza Viruses

    Science.gov (United States)

    ... Address What's this? Submit What's this? Submit Button Influenza Types Seasonal Avian Swine Variant Pandemic Other Information on Swine Influenza/Variant Influenza Virus Language: English (US) Español Recommend ...

  3. The challenge of detecting classical swine fever virus circulation in wild boar (Sus scrofa): Simulation of sampling options

    DEFF Research Database (Denmark)

    Schulz, Jana; Schulz, Katja; Blome, Sandra

    2016-01-01

    investigations play a major role in the early detection of new introductions and in regions immunized with a conventional vaccine. The required financial resources and personnel for reliable testing are often large, and sufficient sample sizes to detect low virus prevalences are difficult to obtain. We conducted...

  4. Pig traders' networks on the Kenya-Uganda border highlight potential for mitigation of African swine fever virus transmission and improved ASF disease risk management.

    Science.gov (United States)

    Lichoti, Jacqueline Kasiiti; Davies, Jocelyn; Maru, Yiheyis; Kitala, Philip M; Githigia, Samuel M; Okoth, Edward; Bukachi, Salome A; Okuthe, Sam; Bishop, Richard P

    2017-05-01

    We applied social network analysis to pig trader networks on the Kenya-Uganda border. Social network analysis is a recently developed tool, which is useful for understanding value chains and improving disease control policies. We interviewed a sample of 33 traders about their experiences with trade and African swine fever (ASF), analyzed the networks they generated in purchasing pigs and selling pork and their potential contribution to modulating dissemination of the ASF virus (ASFV). The majority of the traders were aware of clinical signs of ASF and the risk of trade transmitting ASFV. Most said they avoided buying pigs from ASF outbreak villages or sick pigs but their experiences also indicated that inadvertent purchase was relatively common. Traders had early knowledge of outbreaks since they were contacted by farmers who had heard rumours and wanted to sell their pigs to avoid the risk of them dying. Individual traders bought pigs in up to nine villages, and up to six traders operated in a village. Although each trade typically spanned less than 5km, networks of the various traders, comprising movements of pigs from source villages to slaughter slabs/sites and retail outlets, and movement of pork to villages where it was consumed, linked up indirectly across the 100km×50km study area and revealed several trade pathways across the Kenya-Uganda border. ASF could potentially spread across this area and beyond through sequential pig and pork transactions. Regulation of the pig and pork trade was minimal in practice. The risk of ASFV being spread by traders was compounded by their use of poorly constructed slaughter slabs/sites with open drainage, ineffective or non-existent meat inspection services, lack of provision for biosecurity in the value chain, and sales of pork to customers who were unaware of the risks to their own pigs from contact with ASF infected pork. More effective regulation is warranted. However, limitations on government capacity, together with

  5. Seroprevalence of African Swine Fever in Senegal, 2006

    Science.gov (United States)

    Seck, Ismaila; Grosbois, Vladimir; Jori, Ferran; Blanco, Esther; Vial, Laurence; Akakpo, Ayayi J.; Bada-Alhambedji, Rianatou; Kone, Philippe; Roger, Francois L.

    2011-01-01

    In Senegal, during 2002–2007, 11 outbreaks of African swine fever (ASF) were reported to the World Organisation for Animal Health. Despite this, little was known of the epidemiology of ASF in the country. To determine the prevalence of ASF in Senegal in 2006, we tested serum specimens collected from a sample of pigs in the 3 main pig-farming regions for antibodies to ASF virus using an ELISA. Of 747 serum samples examined, 126 were positive for ASF, suggesting a prevalence of 16.9%. The estimated prevalences within each of the regions (Fatick, Kolda, and Ziguinchor) were 13.3%, 7.8%, and 22.1%, respectively, with statistical evidence to suggest that the prevalence in Ziguinchor was higher than in Fatick or Kolda. This regional difference is considered in relation to different farming systems and illegal trade with neighboring countries where the infection is endemic. PMID:21192854

  6. Identification of residues within the African swine fever virus DP71L protein required for dephosphorylation of translation initiation factor eIF2α and inhibiting activation of pro-apoptotic CHOP

    Energy Technology Data Exchange (ETDEWEB)

    Barber, Claire; Netherton, Chris; Goatley, Lynnette [The Pirbright Institute, Ash Road, Pirbright, Woking, Surrey GU24 0NF (United Kingdom); Moon, Alice; Goodbourn, Steve [Institute for Infection and Immunity, St. George' s, University of London, London SW17 0RE (United Kingdom); Dixon, Linda, E-mail: linda.dixon@pirbright.ac.uk [The Pirbright Institute, Ash Road, Pirbright, Woking, Surrey GU24 0NF (United Kingdom)

    2017-04-15

    The African swine fever virus DP71L protein recruits protein phosphatase 1 (PP1) to dephosphorylate the translation initiation factor 2α (eIF2α) and avoid shut-off of global protein synthesis and downstream activation of the pro-apoptotic factor CHOP. Residues V16 and F18A were critical for binding of DP71L to PP1. Mutation of this PP1 binding motif or deletion of residues between 52 and 66 reduced the ability of DP71L to cause dephosphorylation of eIF2α and inhibit CHOP induction. The residues LSAVL, between 57 and 61, were also required. PP1 was co-precipitated with wild type DP71L and the mutant lacking residues 52- 66 or the LSAVL motif, but not with the PP1 binding motif mutant. The residues in the LSAVL motif play a critical role in DP71L function but do not interfere with binding to PP1. Instead we propose these residues are important for DP71L binding to eIF2α. - Highlights: •The African swine fever virus DP71L protein recruits protein phosphatase 1 (PP1) to dephosphorylate translation initiation factor eIF2α (eIF2α). •The residues V{sup 16}, F{sup 18} of DP71L are required for binding to the α, β and γ isoforms of PP1 and for DP71L function. •The sequence LSAVL downstream from the PP1 binding site (residues 57–61) are also important for DP71L function. •DP71L mutants of the LSAVL sequence retain ability to co-precipitate with PP1 showing these sequences have a different role to PP1 binding.

  7. The control of classical swine fever in wild boar

    Directory of Open Access Journals (Sweden)

    Volker eMoennig

    2015-11-01

    Full Text Available Classical swine fever (CSF is a viral disease with severe economic consequences for domestic pigs. Natural hosts for the CSF virus (CSFV are members of the family Suidae, i.e. Eurasian wild boar (sus scrofa are also susceptible. CSF in wild boar poses a serious threat to domestic pigs. CSFV is an enveloped RNA virus belonging to the pestivirus genus of the Flaviviridae family. Transmission of the infection is usually by direct contact or by feeding of contaminated meat products. In recent decades CSF has been successfully eradicated from Australia, North America, and the European Union. In areas with dense wild boar populations CSF tends to become endemic whereas it is often self-limiting in small, less dense populations. In recent decades eradication strategies of CSF in wild boar have been improved considerably. The reduction of the number of susceptible animals to a threshold level where the basic reproductive number is R0<1 is the major goal of all control efforts. Depending on the epidemiological situation, hunting measures combined with strict hygiene may be effective in areas with a relatively low density of wild boar. Oral immunization was shown to be highly effective in endemic situations in areas with a high density of wild boar.

  8. Pandemic swine influenza virus: Preparedness planning | Ojogba ...

    African Journals Online (AJOL)

    The novel H1N1 influenza virus that emerged in humans in Mexico in early 2009 and transmitted efficiently in the human population with global spread was declared a pandemic strain. The introduction of different avian and human influenza virus genes into swine influenza viruses often result in viruses of increased fitness ...

  9. Classical Swine Fever and Avian Influenza epidemcis: Lessons learned

    NARCIS (Netherlands)

    Elbers, A.R.; Loeffen, W.L.A.; Koch, G.

    2012-01-01

    This publication is based on a talk which was held in the course of the spring symposium „Impfen statt Keulen“ of the Akademie für Tiergesundheit (AfT) 2011 in Wiesbaden-Naurod. Experience with recent large-scale epidemics of Classical Swine Fever and Avian Influenza – among others in the

  10. Comparison of clinical and paraclinical parameters as tools for early diagnosis of classical swine fever

    DEFF Research Database (Denmark)

    Lohse, Louise; Uttenthal, Åse; Nielsen, Jens

    Comparison of clinical and paraclinical parameters as tools for early diagnosis of classical swine fever. Louise Lohse, Åse Uttenthal, Jens Nielsen. National Veterinary Institute, Division of Virology, Lindholm, Technical University of Denmark. Introduction: In order to limit the far-reaching socio......-economic as well as the animal welfare consequences of an outbreak of classical swine fever (CSF), early diagnosis is essential. However, host-virus interactions strongly influence the course of CSF disease, and the clinical feature is not clear, thus complicating the diagnostic perspective. At the National...... Veterinary Institute, in Denmark, we are conducting a series of animal experiments under standardized conditions in order to investigate new parameters of clinical as well as paraclinical nature that holds the potential as diagnostic tools to improve early detection of CSF. In three recent studies, weaned...

  11. A multiplex RT-PCR assay for the rapid and differential diagnosis of classical swine fever and other pestivirus infections.

    Science.gov (United States)

    Díaz de Arce, Heidy; Pérez, Lester J; Frías, Maria T; Rosell, Rosa; Tarradas, Joan; Núñez, José I; Ganges, Llilianne

    2009-11-18

    Classical swine fever is a highly contagious viral disease causing severe economic losses in pig production almost worldwide. All pestivirus species can infect pigs, therefore accurate and rapid pestivirus detection and differentiation is of great importance to assure control measures in swine farming. Here we describe the development and evaluation of a novel multiplex, highly sensitive and specific RT-PCR for the simultaneous detection and rapid differentiation between CSFV and other pestivirus infections in swine. The universal and differential detection was based on primers designed to amplify a fragment of the 5' non-coding genome region for the detection of pestiviruses and a fragment of the NS5B gene for the detection of classical swine fever virus. The assay proved to be specific when different pestivirus strains from swine and ruminants were evaluated. The analytical sensitivity was estimated to be as little as 0.89TCID(50). The assay analysis of 30 tissue homogenate samples from naturally infected and non-CSF infected animals and 40 standard serum samples evaluated as part of two European Inter-laboratory Comparison Tests conducted by the European Community Reference Laboratory, Hanover, Germany proved that the multiplex RT-PCR method provides a rapid, highly sensitive, and cost-effective laboratory diagnosis for classical swine fever and other pestivirus infections in swine.

  12. Classical swine fever vaccines-State-of-the-art.

    Science.gov (United States)

    Blome, Sandra; Moß, Claudia; Reimann, Ilona; König, Patricia; Beer, Martin

    2017-07-01

    Due to its impact on animal health and pig industry, classical swine fever (CSF) is still one of the most important viral diseases of pigs. To control the disease, safe and highly efficacious live attenuated vaccines exist for decades. These vaccines have usually outstanding efficacy and safety but lack differentiability of infected from vaccinated animals (DIVA or marker strategy). In contrast, the first generation of E2 subunit marker vaccines shows constraints in efficacy, application, and production. To overcome these limitations, new generations of marker vaccines are developed. A wide range of approaches have been tried including recombinant vaccines, recombinant inactivated vaccines or subunit vaccines, vector vaccines, and DNA/RNA vaccines. During the last years, especially attenuated deletion vaccines or chimeric constructs have shown potential. At present, especially two new constructs have been intensively tested, the adenovirus-delivered, Semliki Forest virus replicon-vectored marker vaccine candidate "rAdV-SFV-E2" and the pestivirus chimera "CP7_E2alf". The later was recently licensed by the European Medicines Agency. Under field conditions, all marker vaccines have to be accompanied by a potent test system. Particularly this point shows still weaknesses and it is important to embed vaccination in a well-established vaccination strategy and a suitable diagnostic workflow. In summary, conventional vaccines are a standard in terms of efficacy. However, only vaccines with DIVA will allow improved eradication strategies e.g. also under emergency vaccination conditions in free regions. To answer this demand, new generations of marker vaccines have been developed and add now to the tool box of CSF control. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Phylodynamics and evolutionary epidemiology of African swine fever p72-CVR genes in Eurasia and Africa.

    Science.gov (United States)

    Alkhamis, Moh A; Gallardo, Carmina; Jurado, Cristina; Soler, Alejandro; Arias, Marisa; Sánchez-Vizcaíno, José M

    2018-01-01

    African swine fever (ASF) is a complex infectious disease of swine that constitutes devastating impacts on animal health and the world economy. Here, we investigated the evolutionary epidemiology of ASF virus (ASFV) in Eurasia and Africa using the concatenated gene sequences of the viral protein 72 and the central variable region of isolates collected between 1960 and 2015. We used Bayesian phylodynamic models to reconstruct the evolutionary history of the virus, to identify virus population demographics and to quantify dispersal patterns between host species. Results suggest that ASFV exhibited a significantly high evolutionary rate and population growth through time since its divergence in the 18th century from East Africa, with no signs of decline till recent years. This increase corresponds to the growing pig trade activities between continents during the 19th century, and may be attributed to an evolutionary drift that resulted from either continuous circulation or maintenance of the virus within Africa and Eurasia. Furthermore, results implicate wild suids as the ancestral host species (root state posterior probability = 0.87) for ASFV in the early 1700s in Africa. Moreover, results indicate the transmission cycle between wild suids and pigs is an important cycle for ASFV spread and maintenance in pig populations, while ticks are an important natural reservoir that can facilitate ASFV spread and maintenance in wild swine populations. We illustrated the prospects of phylodynamic methods in improving risk-based surveillance, support of effective animal health policies, and epidemic preparedness in countries at high risk of ASFV incursion.

  14. Quantitative approach for the risk assessment of African swine fever and Classical swine fever introduction into the United States through legal imports of pigs and swine products.

    Directory of Open Access Journals (Sweden)

    Diana María Herrera-Ibatá

    Full Text Available The US livestock safety strongly depends on its capacity to prevent the introduction of Transboundary Animal Diseases (TADs. Therefore, accurate and updated information on the location and origin of those potential TADs risks is essential, so preventive measures as market restrictions can be put on place. The objective of the present study was to evaluate the current risk of African swine fever (ASF and Classical swine fever (CSF introduction into the US through the legal importations of live pigs and swine products using a quantitative approach that could be later applied to other risks. Four quantitative stochastic risk assessment models were developed to estimate the monthly probabilities of ASF and CSF release into the US, and the exposure of susceptible populations (domestic and feral swine to these introductions at state level. The results suggest a low annual probability of either ASF or CSF introduction into the US, by any of the analyzed pathways (5.5*10-3. Being the probability of introduction through legal imports of live pigs (1.8*10-3 for ASF, and 2.5*10-3 for CSF higher than the risk of legally imported swine products (8.90*10-4 for ASF, and 1.56*10-3 for CSF. This could be caused due to the low probability of exposure associated with this type of commodity (products. The risk of feral pigs accessing to swine products discarded in landfills was slightly higher than the potential exposure of domestic pigs through swill feeding. The identification of the months at highest risk, the origin of the higher risk imports, and the location of the US states most vulnerable to those introductions (Iowa, Minnesota and Wisconsin for live swine and California, Florida and Texas for swine products, is valuable information that would help to design prevention, risk-mitigation and early-detection strategies that would help to minimize the catastrophic consequences of potential ASF/CSF introductions into the US.

  15. [An overview on swine influenza viruses].

    Science.gov (United States)

    Yang, Shuai; Zhu, Wen-Fei; Shu, Yue-Long

    2013-05-01

    Swine influenza viruses (SIVs) are respiratory pathogens of pigs. They cause both economic bur den in livestock-dependent industries and serious global public health concerns in humans. Because of their dual susceptibility to human and avian influenza viruses, pigs are recognized as intermediate hosts for genetic reassortment and interspecies transmission. Subtypes H1N1, H1N2, and H3N2 circulate in swine populations around the world, with varied origin and genetic characteristics among different continents and regions. In this review, the role of pigs in evolution of influenza A viruses, the genetic evolution of SIVs and interspecies transmission of SIVs are described. Considering the possibility that pigs might produce novel influenza viruses causing more outbreaks and pandemics, routine epidemiological surveillance of influenza viruses in pig populations is highly recommended.

  16. Validation of a Real Time PCR for Classical Swine Fever Diagnosis

    Directory of Open Access Journals (Sweden)

    Natanael Lamas Dias

    2014-01-01

    Full Text Available The viral disease classical swine fever (CSF, caused by a Pestivirus, is one of the major causes of economic losses for pig farming. The aim of this work was to validate a RT-qPCR using Taqman for detection of CSF in swine tissues. The parameters for the validation followed the specifications of the Manual of Diagnostic Tests and Vaccines for Terrestrial Animals of the World Organization for Animal Health (OIE and the guide ABNT NBR ISO/IEC 17025:2005. The analysis of the 5′NTR region of CSF virus was performed in 145 samples from 29 infected pigs and in 240 samples from 80 pigs originated in the Brazilian CSF-free zone. The tissues tested were spleen, kidney, blood, tonsils, and lymph nodes. Sequencing of the positive samples for 5′NTR region was performed to evaluate the specificity of the RT-qPCR. Tests performed for the RT-qPCR validation demonstrated that the PCR assay was efficient in detecting RNA from CSF virus in all materials from different tissues of infected animals. Furthermore, RNA from CSF virus was not detected in samples of swine originated from the Brazilian CSF-free zone. Hence, it is concluded that RT-qPCR can be used as a complementary diagnostic for CSF.

  17. Validation of a real time PCR for classical Swine Fever diagnosis.

    Science.gov (United States)

    Dias, Natanael Lamas; Fonseca Júnior, Antônio Augusto; Oliveira, Anapolino Macedo; Sales, Erica Bravo; Alves, Bruna Rios Coelho; Dorella, Fernanda Alves; Camargos, Marcelo Fernandes

    2014-01-01

    The viral disease classical swine fever (CSF), caused by a Pestivirus, is one of the major causes of economic losses for pig farming. The aim of this work was to validate a RT-qPCR using Taqman for detection of CSF in swine tissues. The parameters for the validation followed the specifications of the Manual of Diagnostic Tests and Vaccines for Terrestrial Animals of the World Organization for Animal Health (OIE) and the guide ABNT NBR ISO/IEC 17025:2005. The analysis of the 5'NTR region of CSF virus was performed in 145 samples from 29 infected pigs and in 240 samples from 80 pigs originated in the Brazilian CSF-free zone. The tissues tested were spleen, kidney, blood, tonsils, and lymph nodes. Sequencing of the positive samples for 5'NTR region was performed to evaluate the specificity of the RT-qPCR. Tests performed for the RT-qPCR validation demonstrated that the PCR assay was efficient in detecting RNA from CSF virus in all materials from different tissues of infected animals. Furthermore, RNA from CSF virus was not detected in samples of swine originated from the Brazilian CSF-free zone. Hence, it is concluded that RT-qPCR can be used as a complementary diagnostic for CSF.

  18. Validation of a Real Time PCR for Classical Swine Fever Diagnosis

    Science.gov (United States)

    Dias, Natanael Lamas; Fonseca Júnior, Antônio Augusto; Oliveira, Anapolino Macedo; Sales, Érica Bravo; Alves, Bruna Rios Coelho; Dorella, Fernanda Alves

    2014-01-01

    The viral disease classical swine fever (CSF), caused by a Pestivirus, is one of the major causes of economic losses for pig farming. The aim of this work was to validate a RT-qPCR using Taqman for detection of CSF in swine tissues. The parameters for the validation followed the specifications of the Manual of Diagnostic Tests and Vaccines for Terrestrial Animals of the World Organization for Animal Health (OIE) and the guide ABNT NBR ISO/IEC 17025:2005. The analysis of the 5′NTR region of CSF virus was performed in 145 samples from 29 infected pigs and in 240 samples from 80 pigs originated in the Brazilian CSF-free zone. The tissues tested were spleen, kidney, blood, tonsils, and lymph nodes. Sequencing of the positive samples for 5′NTR region was performed to evaluate the specificity of the RT-qPCR. Tests performed for the RT-qPCR validation demonstrated that the PCR assay was efficient in detecting RNA from CSF virus in all materials from different tissues of infected animals. Furthermore, RNA from CSF virus was not detected in samples of swine originated from the Brazilian CSF-free zone. Hence, it is concluded that RT-qPCR can be used as a complementary diagnostic for CSF. PMID:24818039

  19. History of Swine influenza viruses in Asia.

    Science.gov (United States)

    Zhu, Huachen; Webby, Richard; Lam, Tommy T Y; Smith, David K; Peiris, Joseph S M; Guan, Yi

    2013-01-01

    The pig is one of the main hosts of influenza A viruses and plays important roles in shaping the current influenza ecology. The occurrence of the 2009 H1N1 pandemic influenza virus demonstrated that pigs could independently facilitate the genesis of a pandemic influenza strain. Genetic analyses revealed that this virus was derived by reassortment between at least two parent swine influenza viruses (SIV), from the northern American triple reassortant H1N2 (TR) and European avian-like H1N1 (EA) lineages. The movement of live pigs between different continents and subsequent virus establishment are preconditions for such a reassortment event to occur. Asia, especially China, has the largest human and pig populations in the world, and seems to be the only region frequently importing pigs from other continents. Virological surveillance revealed that not only classical swine H1N1 (CS), and human-origin H3N2 viruses circulated, but all of the EA, TR and their reassortant variants were introduced into and co-circulated in pigs in this region. Understanding the long-term evolution and history of SIV in Asia would provide insights into the emergence of influenza viruses with epidemic potential in swine and humans.

  20. Influenza D Virus Infection in Feral Swine Populations, United States.

    Science.gov (United States)

    Ferguson, Lucas; Luo, Kaijian; Olivier, Alicia K; Cunningham, Fred L; Blackmon, Sherry; Hanson-Dorr, Katie; Sun, Hailiang; Baroch, John; Lutman, Mark W; Quade, Bianca; Epperson, William; Webby, Richard; DeLiberto, Thomas J; Wan, Xiu-Feng

    2018-06-01

    Influenza D virus (IDV) has been identified in domestic cattle, swine, camelid, and small ruminant populations across North America, Europe, Asia, South America, and Africa. Our study investigated seroprevalence and transmissibility of IDV in feral swine. During 2012-2013, we evaluated feral swine populations in 4 US states; of 256 swine tested, 57 (19.1%) were IDV seropositive. Among 96 archived influenza A virus-seropositive feral swine samples collected from 16 US states during 2010-2013, 41 (42.7%) were IDV seropositive. Infection studies demonstrated that IDV-inoculated feral swine shed virus 3-5 days postinoculation and seroconverted at 21 days postinoculation; 50% of in-contact naive feral swine shed virus, seroconverted, or both. Immunohistochemical staining showed viral antigen within epithelial cells of the respiratory tract, including trachea, soft palate, and lungs. Our findings suggest that feral swine might serve an important role in the ecology of IDV.

  1. A Review of African Swine Fever and the Potential for Introduction into the United States and the Possibility of Subsequent Establishment in Feral Swine and Native Ticks.

    Science.gov (United States)

    Brown, Vienna R; Bevins, Sarah N

    2018-01-01

    African swine fever (ASF) is caused by African swine fever virus (ASFV), which can cause substantial morbidity and mortality events in swine. The virus can be transmitted via direct and indirect contacts with infected swine, their products, or competent vector species, especially Ornithodoros ticks. Africa and much of Eastern Europe are endemic for ASF; a viral introduction to countries that are currently ASF free could have severe economic consequences due to the loss of production from infected animals and the trade restrictions that would likely be imposed as a result of an outbreak. We identified vulnerabilities that could lead to ASFV introduction or persistence in the United States or other ASF-free regions. Both legal and illegal movements of live animals, as well as the importation of animal products, byproducts, and animal feed, pose a risk of virus introduction. Each route is described, and current regulations designed to prevent ASFV and other pathogens from entering the United States are outlined. Furthermore, existing ASFV research gaps are highlighted. Laboratory experiments to evaluate multiple species of Ornithodoros ticks that have yet to be characterized would be useful to understand vector competence, host preferences, and distribution of competent soft tick vectors in relation to high pig production areas as well as regions with high feral swine (wild boar or similar) densities. Knowledge relative to antigenic viral proteins that contribute to host response and determination of immune mechanisms that lead to protection are foundational in the quest for a vaccine. Finally, sampling of illegally imported and confiscated wild suid products for ASFV could shed light on the types of products being imported and provide a more informed perspective relative to the risk of ASFV importation.

  2. A Review of African Swine Fever and the Potential for Introduction into the United States and the Possibility of Subsequent Establishment in Feral Swine and Native Ticks

    Directory of Open Access Journals (Sweden)

    Vienna R. Brown

    2018-02-01

    Full Text Available African swine fever (ASF is caused by African swine fever virus (ASFV, which can cause substantial morbidity and mortality events in swine. The virus can be transmitted via direct and indirect contacts with infected swine, their products, or competent vector species, especially Ornithodoros ticks. Africa and much of Eastern Europe are endemic for ASF; a viral introduction to countries that are currently ASF free could have severe economic consequences due to the loss of production from infected animals and the trade restrictions that would likely be imposed as a result of an outbreak. We identified vulnerabilities that could lead to ASFV introduction or persistence in the United States or other ASF-free regions. Both legal and illegal movements of live animals, as well as the importation of animal products, byproducts, and animal feed, pose a risk of virus introduction. Each route is described, and current regulations designed to prevent ASFV and other pathogens from entering the United States are outlined. Furthermore, existing ASFV research gaps are highlighted. Laboratory experiments to evaluate multiple species of Ornithodoros ticks that have yet to be characterized would be useful to understand vector competence, host preferences, and distribution of competent soft tick vectors in relation to high pig production areas as well as regions with high feral swine (wild boar or similar densities. Knowledge relative to antigenic viral proteins that contribute to host response and determination of immune mechanisms that lead to protection are foundational in the quest for a vaccine. Finally, sampling of illegally imported and confiscated wild suid products for ASFV could shed light on the types of products being imported and provide a more informed perspective relative to the risk of ASFV importation.

  3. Diagnostic value of meat juice in early detection of classical swine fever infection

    DEFF Research Database (Denmark)

    Lohse, Louise; Uttenthal, Åse; Rasmussen, Thomas Bruun

    2011-01-01

    samples originated from pigs infected with low virulence CSFV strains and/or when samples were collected within the first days after infection. In conclusion, while not the first choice for sample material for CSFV diagnosis, meat juice may constitute a useful alternative for herd-based studies or when......To evaluate the diagnostic potential of meat juice for early detection of Classical swine fever virus (CSFV), meat juice and serum samples from pigs experimentally infected with different strains of CSFV were compared for virus load. From all samples, viral RNA was extracted by automated procedure...... blood and/or target organ material is not available. Strain virulence and time points for sample collection after infection are factors of importance for diagnostic success....

  4. The global antigenic diversity of swine influenza A viruses

    DEFF Research Database (Denmark)

    Lewis, Nicola S; Russell, Colin A; Langat, Pinky

    2016-01-01

    Swine influenza presents a substantial disease burden for pig populations worldwide and poses a potential pandemic threat to humans. There is considerable diversity in both H1 and H3 influenza viruses circulating in swine due to the frequent introductions of viruses from humans and birds coupled...... with geographic segregation of global swine populations. Much of this diversity is characterized genetically but the antigenic diversity of these viruses is poorly understood. Critically, the antigenic diversity shapes the risk profile of swine influenza viruses in terms of their epizootic and pandemic potential...

  5. Swine influenza virus: zoonotic potential and vaccination strategies for the control of avian and swine influenzas.

    Science.gov (United States)

    Thacker, Eileen; Janke, Bruce

    2008-02-15

    Influenza viruses are able to infect humans, swine, and avian species, and swine have long been considered a potential source of new influenza viruses that can infect humans. Swine have receptors to which both avian and mammalian influenza viruses bind, which increases the potential for viruses to exchange genetic sequences and produce new reassortant viruses in swine. A number of genetically diverse viruses are circulating in swine herds throughout the world and are a major cause of concern to the swine industry. Control of swine influenza is primarily through the vaccination of sows, to protect young pigs through maternally derived antibodies. However, influenza viruses continue to circulate in pigs after the decay of maternal antibodies, providing a continuing source of virus on a herd basis. Measures to control avian influenza in commercial poultry operations are dictated by the virulence of the virus. Detection of a highly pathogenic avian influenza (HPAI) virus results in immediate elimination of the flock. Low-pathogenic avian influenza viruses are controlled through vaccination, which is done primarily in turkey flocks. Maintenance of the current HPAI virus-free status of poultry in the United States is through constant surveillance of poultry flocks. Although current influenza vaccines for poultry and swine are inactivated and adjuvanted, ongoing research into the development of newer vaccines, such as DNA, live-virus, or vectored vaccines, is being done. Control of influenza virus infection in poultry and swine is critical to the reduction of potential cross-species adaptation and spread of influenza viruses, which will minimize the risk of animals being the source of the next pandemic.

  6. 9 CFR 94.8 - Pork and pork products from regions where African swine fever exists or is reasonably believed to...

    Science.gov (United States)

    2010-01-01

    ... cultures under conditions which the Administrator has determined are less stringent than those prescribed by this chapter for the importation or use of African swine fever virus or cultures into or within... amended in paragraph (a)(3)(i) by removing the citation “(a)(4)” and adding the words “(a)(5) of this...

  7. Interaction between Mycoplasma hyopneumoniae and Swine Influenza Virus

    Science.gov (United States)

    Thacker, Eileen L.; Thacker, Brad J.; Janke, Bruce H.

    2001-01-01

    An experimental respiratory model was used to investigate the interaction between Mycoplasma hyopneumoniae and swine influenza virus (SIV) in the induction of pneumonia in susceptible swine. Previous studies demonstrated that M. hyopneumoniae, which produces a chronic bronchopneumonia in swine, potentiates a viral pneumonia induced by the porcine reproductive and respiratory syndrome virus (PRRSV). In this study, pigs were inoculated with M. hyopneumoniae 21 days prior to inoculation with SIV. Clinical disease as characterized by the severity of cough and fever was evaluated daily. Percentages of lung tissue with visual lesions and microscopic lesions were assessed upon necropsy at 3, 7, 14, and 21 days following SIV inoculation. Clinical observations revealed that pigs infected with both SIV and M. hyopneumoniae coughed significantly more than pigs inoculated with a single agent. Macroscopic pneumonia on necropsy at days 3 and 7 was greatest in both SIV-infected groups, with minimal levels of pneumonia in the M. hyopneumoniae-only-infected pigs. At 14 days post-SIV inoculation, pneumonia was significantly more severe in pigs infected with both pathogens. However, by 21 days postinoculation, the level of pneumonia in the dual-infected pigs was similar to that of the M. hyopneumoniae-only-infected group, and the pneumonia in the pigs inoculated with only SIV was nearly resolved. Microscopically, there was no apparent increase in the severity of pneumonia in pigs infected with both agents compared to that of single-agent-challenged pigs. The results of this study found that while pigs infected with both agents exhibited more severe clinical disease, the relationship between the two pathogens lacked the profound potentiation found with dual infection with M. hyopneumoniae and PRRSV. These findings demonstrate that the relationship between mycoplasmas and viruses varies with the individual agent. PMID:11427564

  8. Why is African swine fever still present in Sardinia?

    Science.gov (United States)

    Jurado, C; Fernández-Carrión, E; Mur, L; Rolesu, S; Laddomada, A; Sánchez-Vizcaíno, J M

    2018-04-01

    African swine fever (ASF) is an infectious disease of swine that has been present in Sardinia since 1978. Soon after introduction of the disease, several control and eradication programmes were established with limited success. Some researchers attributed the persistence of the disease in central and eastern areas to certain socio-economic factors, the existence of some local and traditional farming practices (i.e., unregistered free-ranging pigs known as brado animals) and the high density of wild boar in the region. In the past, scarcity of swine data in Sardinia complicated the evaluation and study of ASF on the island. More complete, accurate and reliable information on pig farms has become available as a result of the most recent eradication programmes. Here, we perform statistical modelling based on these data and the known distribution of domestic pig and wild boar to identify the main risk factors that have caused ASF persistence in Sardinia. Our results categorized, identified and quantified nine significant risk factors, six of which have not been previously described. The most significant factors were the number of medium-sized farms, the presence of brado animals and the combination of estimated wild boar density and mean altitude above sea level. Based on these factors, we identified regions in eastern and central Sardinia to be at greatest risk of ASF persistence; these regions are also where the disease has traditionally been endemic. Based on these risk factors, we propose specific control measures aimed at mitigating such risks and eradicating ASF from the island. © 2017 Blackwell Verlag GmbH.

  9. Classical swine fever in pigs: recent developments and future perspectives.

    Science.gov (United States)

    Chander, Vishal; Nandi, S; Ravishankar, C; Upmanyu, V; Verma, Rishendra

    2014-06-01

    Classical swine fever (CSF) is one of the most devastating epizootic diseases of pigs, causing high morbidity and mortality worldwide. The diversity of clinical signs and similarity in disease manifestations to other diseases make CSF difficult to diagnose with certainty. The disease is further complicated by the presence of a number of different strains belonging to three phylogenetic groups. Advanced diagnostic techniques allow detection of antigens or antibodies in clinical samples, leading to implementation of proper and effective control programs. Polymerase chain reaction (PCR)-based methods, including portable real-time PCR, provide diagnosis in a few hours with precision and accuracy, even at the point of care. The disease is controlled by following a stamping out policy in countries where vaccination is not practiced, whereas immunization with live attenuated vaccines containing the 'C' strain is effectively used to control the disease in endemic countries. To overcome the problem of differentiation of infected from vaccinated animals, different types of marker vaccines, with variable degrees of efficacy, along with companion diagnostic assays have been developed and may be useful in controlling and even eradicating the disease in the foreseeable future. The present review aims to provide an overview and status of CSF as a whole with special reference to swine husbandry in India.

  10. The African swine fever control zone in South Africa and its current relevance

    Directory of Open Access Journals (Sweden)

    Noluvuyo R. Magadla

    2016-05-01

    Full Text Available African swine fever (ASF has been reported in South Africa since the early 20th century. The disease has been controlled and confined to northern South Africa over the past 80 years by means of a well-defined boundary line, with strict control measures and movement restrictions north of this line. In 2012, the first outbreak of ASF outside the ASF control zone since 1996 occurred. The objective of this study was to evaluate the current relevance of the ASF control line as a demarcation line between endemic ASF (north areas and ASF-free (south area and to determine whether there was a need to realign its trajectory, given the recent outbreaks of ASF, global climate changes and urban development since the line’s inception. A study of ASF determinants was conducted in an area 20 km north and 20 km south of the ASF control line, in Limpopo, Mpumalanga, North West and Gauteng provinces between May 2008 and September 2012. The study confirmed that warthogs, warthog burrows and the soft tick reservoir, Ornithodoros moubata, are present south of the ASF control line, but no virus or viral DNA was detected in these ticks. There appears to be an increasing trend in the diurnal maximum temperature and a decrease in humidity along the line, but the impact of these changes is uncertain. No discernible changes in minimum temperatures and average rainfall along the disease control line were observed between 1992 and 2014. Even though the reservoirs were found south of the ASF boundary line, the study concluded that there was no need to realign the trajectory of the ASF disease control line, with the exception of Limpopo Province. However, the provincial surveillance programmes for the reservoir, vector and ASF virus south of this line needs to be maintained and intensified as changing farming practices may favour the spread of ASF virus beyond the control line. Keywords: African swine fever; warthog burrow; Ornithodoros moubata;control line

  11. The structure of classical swine fever virus N(pro: a novel cysteine Autoprotease and zinc-binding protein involved in subversion of type I interferon induction.

    Directory of Open Access Journals (Sweden)

    Keerthi Gottipati

    Full Text Available Pestiviruses express their genome as a single polypeptide that is subsequently cleaved into individual proteins by host- and virus-encoded proteases. The pestivirus N-terminal protease (N(pro is a cysteine autoprotease that cleaves between its own C-terminus and the N-terminus of the core protein. Due to its unique sequence and catalytic site, it forms its own cysteine protease family C53. After self-cleavage, N(pro is no longer active as a protease. The released N(pro suppresses the induction of the host's type-I interferon-α/β (IFN-α/β response. N(pro binds interferon regulatory factor-3 (IRF3, the key transcriptional activator of IFN-α/β genes, and promotes degradation of IRF3 by the proteasome, thus preventing induction of the IFN-α/β response to pestivirus infection. Here we report the crystal structures of pestivirus N(pro. N(pro is structurally distinct from other known cysteine proteases and has a novel "clam shell" fold consisting of a protease domain and a zinc-binding domain. The unique fold of N(pro allows auto-catalysis at its C-terminus and subsequently conceals the cleavage site in the active site of the protease. Although many viruses interfere with type I IFN induction by targeting the IRF3 pathway, little information is available regarding structure or mechanism of action of viral proteins that interact with IRF3. The distribution of amino acids on the surface of N(pro involved in targeting IRF3 for proteasomal degradation provides insight into the nature of N(pro's interaction with IRF3. The structures thus establish the mechanism of auto-catalysis and subsequent auto-inhibition of trans-activity of N(pro, and its role in subversion of host immune response.

  12. Genotype I of Japanese Encephalitis Virus Virus-like Particles Elicit Sterilizing Immunity against Genotype I and III Viral Challenge in Swine.

    Science.gov (United States)

    Fan, Yi-Chin; Chen, Jo-Mei; Lin, Jen-Wei; Chen, Yi-Ying; Wu, Guan-Hong; Su, Kuan-Hsuan; Chiou, Ming-Tang; Wu, Shang-Rung; Yin, Ji-Hang; Liao, Jiunn-Wang; Chang, Gwong-Jen J; Chiou, Shyan-Song

    2018-05-10

    Swine are a critical amplifying host involved in human Japanese encephalitis (JE) outbreaks. Cross-genotypic immunogenicity and sterile protection are important for the current genotype III (GIII) virus-derived vaccines in swine, especially now that emerging genotype I (GI) JE virus (JEV) has replaced GIII virus as the dominant strain. Herein, we aimed to develop a system to generate GI JEV virus-like particles (VLPs) and evaluate the immunogenicity and protection of the GI vaccine candidate in mice and specific pathogen-free swine. A CHO-heparan sulfate-deficient (CHO-HS(-)) cell clone, named 51-10 clone, stably expressing GI-JEV VLP was selected and continually secreted GI VLPs without signs of cell fusion. 51-10 VLPs formed a homogeneously empty-particle morphology and exhibited similar antigenic activity as GI virus. GI VLP-immunized mice showed balanced cross-neutralizing antibody titers against GI to GIV viruses (50% focus-reduction micro-neutralization assay titers 71 to 240) as well as potent protection against GI or GIII virus infection. GI VLP-immunized swine challenged with GI or GIII viruses showed no fever, viremia, or viral RNA in tonsils, lymph nodes, and brains as compared with phosphate buffered saline-immunized swine. We thus conclude GI VLPs can provide sterile protection against GI and GIII viruses in swine.

  13. Simulation of Spread of African Swine Fever, Including the Effects of Residues from Dead Animals

    DEFF Research Database (Denmark)

    Hisham Beshara Halasa, Tariq; Boklund, Anette; Bøtner, Anette

    2016-01-01

    To study the spread of African swine fever (ASF) within a pig unit and the impact of unit size on ASF spread, a simulation model was created. In the model, an animal can be in one of the following stages: susceptible, latent, subclinical, clinical, or recovered. Animals can be infectious during...... the subclinical stage and are fully infectious during the clinical stage. ASF virus (ASFV) infection through residues of dead animals in the slurries was also modeled in an exponentially fading-out pattern. Low and high transmission rates for ASFV were tested in the model. Robustness analysis was carried out...... in order to study the impact of uncertain parameters on model predictions. The results showed that the disease may fade out within the pig unit without a major outbreak. Furthermore, they showed that spread of ASFV is dependent on the infectiousness of subclinical animals and the residues of dead animals...

  14. Analysis of HDAC6 and BAG3-Aggresome Pathways in African Swine Fever Viral Factory Formation

    Directory of Open Access Journals (Sweden)

    Raquel Muñoz-Moreno

    2015-04-01

    Full Text Available African swine fever virus (ASFV is a double-stranded DNA virus causing a hemorrhagic fever disease with high mortality rates and severe economic losses in pigs worldwide. ASFV replicates in perinuclear sites called viral factories (VFs that are morphologically similar to cellular aggresomes. This fact raises the possibility that both VFs and aggresomes may be the same structure. However, little is known about the process involved in the formation of these viral replication platforms. In order to expand our knowledge on the assembly of ASFV replication sites, we have analyzed the involvement of both canonical aggresome pathways in the formation of ASFV VFs: HDAC6 and BAG3. HDAC6 interacts with a component of the dynein motor complex (dynactin/p150Glued and ubiquitinated proteins, transporting them to the microtubule-organizing center (MTOC and leading to aggresome formation, while BAG3 is mediating the recruitment of non-ubiquitinated proteins through a similar mechanism. Tubacin-mediated HDAC6 inhibition and silencing of BAG3 pathways, individually or simultaneously, did not prevent ASFV VF formation. These findings show that HDAC6 and Bag3 are not required for VFs formation suggesting that aggresomes and VFs are not the same structures. However, alternative unexplored pathways may be involved in the formation of aggresomes.

  15. Selected aspects related to epidemiology, pathogenesis, immunity, and control of African swine fever

    Directory of Open Access Journals (Sweden)

    Woźniakowski Grzegorz

    2016-06-01

    Full Text Available African swine fever (ASF is currently one of the most severe viral infections of domestic pigs, wild boars, and other hosts belonging to Suidae family. ASF is also considered as the most complex and devastating infectious and haemorrhagic disease of swine due to its severe socio-economic impact and transboundary character. ASF it is a notifiable disease and due to the lack of specific treatment and vaccine, the disease can be only limited by the administrative measures comprising wild boar hunting and stamping out of affected pigs. ASF occurred for the first time in Kenya in 1921 while in Europe (Portugal the virus was detected at the end of the 1950s. In spite of successful eradication of this threat in a number of affected regions, the virus remains endemic in both feral and domestic pigs in Africa and Sardinia. The ‘new era’ of ASF started in 2007 after its re-introduction to Georgia. Following its intensive expansion, the virus spread to other Caucasian countries, including the territory of the Russian Federation. In 2014 the virus reached Ukraine, Belarus, and, consequently, European Union countries: Lithuania, Latvia, Estonia, and Poland. The occurrence of ASF in wild boars and pigs had a severe impact on both epidemiology and economy because of the national and international transport and trade consequences. Up to date, starting from the February 2014, eighty ASF cases in wild boar and three outbreaks in domestic pigs have been diagnosed. Taking into account the diverse rate of spread in Poland, this review aims to present and discuss the current state of knowledge on ASF including its epidemiology, pathology, transmission, and perspectives of control.

  16. Two outbreaks of classical swine fever in wild boar in France.

    Science.gov (United States)

    Pol, F; Rossi, S; Mesplède, A; Kuntz-Simon, G; Le Potier, M-F

    2008-06-21

    In 2002 and 2003, two successive outbreaks of classical swine fever were declared in wild boar in northern France. The first was in Moselle, near the town of Thionville and the border with Luxembourg, and the second was in the northern Vosges area, near the German border. The outbreaks were investigated by serological and virological diagnosis of dead or shot animals. Hunting restrictions were applied to limit the spread of the outbreaks. The virus was detected eight times between April and July 2002 in the Thionville area, an area well delimited by natural or artificial barriers such as rivers or highways. Cooperation between the authorities concerned was good, and hunting restrictions were applied for one year. No virus was detected after July 2002 and the Thionville outbreak was officially considered over in March 2005. In the northern Vosges the situation was different, with no barriers to animal movements, continuous forest, difficulties in establishing hunting restrictions in this huge area, and the circulation of the virus in Germany close to the frontier. Virus of a different strain from that isolated in the Thionville outbreak was still being isolated in the northern Vosges in 2004, and owing to the failure of the hunting restrictions, the French health authorities decided to vaccinate wild boar.

  17. Population dynamics of swine influenza virus in finishing pigs

    NARCIS (Netherlands)

    Loeffen, W.L.A.

    2008-01-01

    Influenza virus infections in swine were first noticed in the US in 1918, during the human pandemic of the Spanish flu. In Europe, seroprevalences for the three most common swine influenza strains at the moment, H1N1, H3N2 and H1N2, range from 20-80% in finishing pigs at the end of the finishing

  18. Pandemic Swine-Origin H1N1 Influenza Virus Replicates to Higher Levels and Induces More Fever and Acute Inflammatory Cytokines in Cynomolgus versus Rhesus Monkeys and Can Replicate in Common Marmosets.

    Directory of Open Access Journals (Sweden)

    Petra Mooij

    Full Text Available The close immunological and physiological resemblance with humans makes non-human primates a valuable model for studying influenza virus pathogenesis and immunity and vaccine efficacy against infection. Although both cynomolgus and rhesus macaques are frequently used in influenza virus research, a direct comparison of susceptibility to infection and disease has not yet been performed. In the current study a head-to-head comparison was made between these species, by using a recently described swine-origin pandemic H1N1 strain, A/Mexico/InDRE4487/2009. In comparison to rhesus macaques, cynomolgus macaques developed significantly higher levels of virus replication in the upper airways and in the lungs, involving both peak level and duration of virus production, as well as higher increases in body temperature. In contrast, clinical symptoms, including respiratory distress, were more easily observed in rhesus macaques. Expression of sialyl-α-2,6-Gal saccharides, the main receptor for human influenza A viruses, was 50 to 73 times more abundant in trachea and bronchus of cynomolgus macaques relative to rhesus macaques. The study also shows that common marmosets, a New World non-human primate species, are susceptible to infection with pandemic H1N1. The study results favor the cynomolgus macaque as model for pandemic H1N1 influenza virus research because of the more uniform and high levels of virus replication, as well as temperature increases, which may be due to a more abundant expression of the main human influenza virus receptor in the trachea and bronchi.

  19. 9 CFR 96.2 - Prohibition of casings due to African swine fever and bovine spongiform encephalopathy.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Prohibition of casings due to African swine fever and bovine spongiform encephalopathy. 96.2 Section 96.2 Animals and Animal Products ANIMAL... spongiform encephalopathy. (a) Swine casings. The importation of swine casings that originated in or were...

  20. Novel reassortant swine influenza viruses are circulating in Danish pigs

    DEFF Research Database (Denmark)

    Breum, Solvej Østergaard; Hjulsager, Charlotte Kristiane; Trebbien, Ramona

    of the reassortant viruses comprised a HA gene similar to H1 of H1N1 avian-like swine influenza virus (SIV) and a NA gene most closely related to N2 gene of human H3N2 influenza virus that circulated in humans in the mid 1990s. The internal genes of this reassortant virus with the subtype H1avN2hu all belonged...... to the H1N1 avian-like SIV lineages. Until now this novel virus H1avN2hu has only been detected in Danish swine. The other novel reassortant virus contained the HA gene from H1N1pdm09 virus and a NA gene similar to the N2 gene of H3N2 SIV that have been circulating in European swine since the mid 1980s...

  1. Antibody levels to hepatitis E virus in North Carolina swine workers, non-swine workers, swine, and murids.

    Science.gov (United States)

    Withers, Mark R; Correa, Maria T; Morrow, Morgan; Stebbins, Martha E; Seriwatana, Jitvimol; Webster, W David; Boak, Marshall B; Vaughn, David W

    2002-04-01

    In a cross-sectional serosurvey, eastern North Carolina swine workers (n = 165) were compared with non-swine workers (127) for the presence of antibodies to hepatitis E virus as measured by a quantitative immunoglobulin enzyme-linked immunosorbent assay. Using a cutoff of 20 Walter Reed U/ml, swine-exposed subjects had a 4.5-fold higher antibody prevalence (10.9%) than unexposed subjects (2.4%). No evidence of past clinical hepatitis E or unexplained jaundice could be elicited. Swine (84) and mice (61), from farm sites in the same region as exposed subjects, were also tested. Antibody prevalence in swine (overall = 34.5%) varied widely (10.0-91.7%) according to site, but no antibody was detected in mice. Our data contribute to the accumulating evidence that hepatitis E may be a zoonosis and specifically to the concept of it as an occupational infection of livestock workers.

  2. Meta-analysis of classical swine fever prevalence in pigs in India: A 5-year study

    Science.gov (United States)

    Patil, S. S.; Suresh, K. P.; Saha, S.; Prajapati, A.; Hemadri, D.; Roy, P.

    2018-01-01

    Aim: The aim of the study was to determine the overall prevalence of classical swine fever (CSF) in pigs in India, through a systematic review and meta-analysis of published data. Materials and Methods: Consortium for e-Resources in Agriculture, India, Google Scholar, PubMed, annual reports of All India Coordinated Research Project on Animal Disease Monitoring and Surveillance, and All India Animal Disease database of NIVEDI (NADRES) were used for searching and retrieval of CSF prevalence data (seroprevalence, virus antigen, and virus nucleic acid detection) in India using a search strategy combining keywords and related database-specific subject terms from January 2011 to December 2015 in English only. Results: A total of 22 data reports containing 6,158 samples size from 18 states of India were used for the quantitative synthesis, and overall 37% (95% confidence interval [CI]=0.24, 0.51) CSF prevalence in India was estimated. The data were classified into 4 different geographical zones of the country: 20% (95% CI=0.05, 0.55), 31% (95% CI=0.18, 0.47), 55% (95% CI=0.32, 0.76), and 34% (95% CI=0.14, 0.62). CSF prevalence was estimated in northern, eastern, western, and southern regions, respectively. Conclusion: This study indicates that overall prevalence of CSF in India is much lower than individual published reports. PMID:29657420

  3. Five years' experience of classical swine fever polymerase chain reaction ring trials in France.

    Science.gov (United States)

    Po, F; Le Dimna, M; Le Potier, M F

    2011-12-01

    Since 2004, the French National Reference Laboratory for classical swine fever (CSF) has conducted an annual proficiency test (PT) to evaluate the ability of local veterinary laboratories to perform real-time polymerase chain reaction (PCR) for CSF virus. The results of five years of testing (2004-2008) are described here. The PT was conducted under blind conditions on 20 samples. The same batch of samples was used for all five years. The number of laboratories that analysed the samples increased from four in 2004 to 13 in 2008. The results of the PT showed the following: cross-contamination between samples and deficiencies in RNA preparation can occur even in experienced laboratories; sample homogeneity should be checked carefully before selection; samples stored at-80 degrees C for several years remain stable; and poor shipment conditions do not damage the samples with regard to detection of CSF virus genome. These results will enable redesign of the panel to improve the overall quality of the PT, which will encourage laboratories to check and improve their PCR procedures and expertise. This is an excellent way to determine laboratory performance.

  4. Enzootic transmission of yellow fever virus, Venezuela.

    Science.gov (United States)

    Auguste, Albert J; Lemey, Philippe; Bergren, Nicholas A; Giambalvo, Dileyvic; Moncada, Maria; Morón, Dulce; Hernandez, Rosa; Navarro, Juan-Carlos; Weaver, Scott C

    2015-01-01

    Phylogenetic analysis of yellow fever virus (YFV) strains isolated from Venezuela strongly supports YFV maintenance in situ in Venezuela, with evidence of regionally independent evolution within the country. However, there is considerable YFV movement from Brazil to Venezuela and between Trinidad and Venezuela.

  5. Efficacy of chimeric Pestivirus vaccine candidates against classical swine fever: protection and DIVA characteristics.

    Science.gov (United States)

    Eblé, P L; Geurts, Y; Quak, S; Moonen-Leusen, H W; Blome, S; Hofmann, M A; Koenen, F; Beer, M; Loeffen, W L A

    2013-03-23

    Currently no live DIVA (Differentiating Infected from Vaccinated Animals) vaccines against classical swine fever (CSF) are available. The aim of this study was to investigate whether chimeric pestivirus vaccine candidates (CP7_E2alf, Flc11 and Flc9) are able to protect pigs against clinical signs, and to reduce virus shedding and virus transmission, after a challenge with CSF virus (CSFV), 7 or 14 days after a single intramuscular vaccination. In these vaccine candidates, either the E2 or the E(rns) encoding genome region of a bovine viral diarrhoea virus strain were combined with a cDNA copy of CSFV or vice versa. Furthermore, currently available serological DIVA tests were evaluated. The vaccine candidates were compared to the C-strain. All vaccine candidates protected against clinical signs. No transmission to contact pigs was detected in the groups vaccinated with C-strain, CP7_E2alf and Flc11. Limited transmission occurred in the groups vaccinated with Flc9. All vaccine candidates would be suitable to stop on-going transmission of CSFV. For Flc11, no reliable differentiation was possible with the current E(rns)-based DIVA test. For CP7_E2alf, the distribution of the inhibition percentages was such that up to 5% false positive results may be obtained in a large vaccinated population. For Flc9 vaccinated pigs, the E2 ELISA performed very well, with an expected 0.04% false positive results in a large vaccinated population. Both CP7_E2alf and Flc9 are promising candidates to be used as live attenuated marker vaccines against CSF, with protection the best feature of CP7_E2alf, and the DIVA principle the best feature of Flc9. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Social network analysis provides insights into African swine fever epidemiology.

    Science.gov (United States)

    Lichoti, Jacqueline Kasiiti; Davies, Jocelyn; Kitala, Philip M; Githigia, Samuel M; Okoth, Edward; Maru, Yiheyis; Bukachi, Salome A; Bishop, Richard P

    2016-04-01

    Pig movements play a significant role in the spread of economically important infectious diseases such as the African swine fever. Characterization of movement networks between pig farms and through other types of farm and household enterprises that are involved in pig value chains can provide useful information on the role that different participants in the networks play in pathogen transmission. Analysis of social networks that underpin these pig movements can reveal pathways that are important in the transmission of disease, trade in commodities, the dissemination of information and the influence of behavioural norms. We assessed pig movements among pig keeping households within West Kenya and East Uganda and across the shared Kenya-Uganda border in the study region, to gain insight into within-country and trans-boundary pig movements. Villages were sampled using a randomized cluster design. Data were collected through interviews in 2012 and 2013 from 683 smallholder pig-keeping households in 34 villages. NodeXL software was used to describe pig movement networks at village level. The pig movement and trade networks were localized and based on close social networks involving family ties, friendships and relationships with neighbours. Pig movement network modularity ranged from 0.2 to 0.5 and exhibited good community structure within the network implying an easy flow of knowledge and adoption of new attitudes and beliefs, but also promoting an enhanced rate of disease transmission. The average path length of 5 defined using NodeXL, indicated that disease could easily reach every node in a cluster. Cross-border boar service between Uganda and Kenya was also recorded. Unmonitored trade in both directions was prevalent. While most pig transactions in the absence of disease, were at a small scale (sales during ASF outbreaks were to traders or other farmers from outside the sellers' village at a range of >10km. The close social relationships between actors in pig

  7. Socio-economic impact of African swine fever outbreak of 2011 and ...

    African Journals Online (AJOL)

    With our findings we can conclude that ASF is still an important transboundary animal disease (TAD) with enormous socio-economic impact that requires concerted efforts of all stakeholders in the enforcement of control and preventive measures. Key words: African swine fever, socio-economic impact, seroprevalence, Isoka ...

  8. Classical Swine Fever Outbreak after Modified Live LOM Strain Vaccination in Naive Pigs, South Korea

    Science.gov (United States)

    Je, Sang H.; Kwon, Taeyong; Yoo, Sung J.; Lee, Dong-Uk; Lee, SeungYoon; Richt, Juergen A.

    2018-01-01

    We report classical swine fever outbreaks occurring in naive pig herds on Jeju Island, South Korea, after the introduction of the LOM vaccine strain. Two isolates from sick pigs had >99% identity with the vaccine stain. LOM strain does not appear safe; its use in the vaccine should be reconsidered. PMID:29553332

  9. Feral Swine in the United States Have Been Exposed to both Avian and Swine Influenza A Viruses.

    Science.gov (United States)

    Martin, Brigitte E; Sun, Hailiang; Carrel, Margaret; Cunningham, Fred L; Baroch, John A; Hanson-Dorr, Katie C; Young, Sean G; Schmit, Brandon; Nolting, Jacqueline M; Yoon, Kyoung-Jin; Lutman, Mark W; Pedersen, Kerri; Lager, Kelly; Bowman, Andrew S; Slemons, Richard D; Smith, David R; DeLiberto, Thomas; Wan, Xiu-Feng

    2017-10-01

    Influenza A viruses (IAVs) in swine can cause sporadic infections and pandemic outbreaks among humans, but how avian IAV emerges in swine is still unclear. Unlike domestic swine, feral swine are free ranging and have many opportunities for IAV exposure through contacts with various habitats and animals, including migratory waterfowl, a natural reservoir for IAVs. During the period from 2010 to 2013, 8,239 serum samples were collected from feral swine across 35 U.S. states and tested against 45 contemporary antigenic variants of avian, swine, and human IAVs; of these, 406 (4.9%) samples were IAV antibody positive. Among 294 serum samples selected for antigenic characterization, 271 cross-reacted with ≥1 tested virus, whereas the other 23 did not cross-react with any tested virus. Of the 271 IAV-positive samples, 236 cross-reacted with swine IAVs, 1 with avian IAVs, and 16 with avian and swine IAVs, indicating that feral swine had been exposed to both swine and avian IAVs but predominantly to swine IAVs. Our findings suggest that feral swine could potentially be infected with both avian and swine IAVs, generating novel IAVs by hosting and reassorting IAVs from wild birds and domestic swine and facilitating adaptation of avian IAVs to other hosts, including humans, before their spillover. Continued surveillance to monitor the distribution and antigenic diversities of IAVs in feral swine is necessary to increase our understanding of the natural history of IAVs. IMPORTANCE There are more than 5 million feral swine distributed across at least 35 states in the United States. In contrast to domestic swine, feral swine are free ranging and have unique opportunities for contact with wildlife, livestock, and their habitats. Our serological results indicate that feral swine in the United States have been exposed to influenza A viruses (IAVs) consistent with those found in both domestic swine and wild birds, with the predominant infections consisting of swine-adapted IAVs

  10. Two genotypes of H1N2 swine influenza viruses appeared among pigs in China.

    Science.gov (United States)

    Xu, Chuantian; Zhu, Qiyun; Yang, Huanliang; Zhang, Xiumei; Qiao, Chuanling; Chen, Yan; Xin, Xiaoguang; Chen, Hualan

    2009-10-01

    H1N2 is one of the main subtypes of influenza, which circulates in swine all over the world. To investigate the prevalence and genetic of H1N2 in swine of China. Two H1N2 swine influenza viruses were isolated from Tianjin and Guangdong province of China in 2004 and 2006, respectively. The molecular evolution of eight gene segments was analyzed. A/Swine/Tianjin/1/2004 has low identity with A/Swine/Guangdong/2006; in the phylogenetic tree of PA gene, A/Swine/Guangdong/1/2006 and A/Swine/Guangxi/1/2006 along with the H1N2 swine isolates of North America formed a cluster; and A/Swine/Tianjin/2004 and A/Swine/Zhejiang/2004, along with the classical H1N1 swine isolates formed another cluster; except that NA gene of A/Swine/Tianjin/1/2004 fell into the cluster of the H3N2 human influenza virus, indicating the reassortment between H3N2 human and H1N1 swine influenza viruses. Two different genotypes of H1N2 appeared among pigs in China. A/swine/Guangdong/1/06 was probably from H1N2 swine influenza viruses of North America; while A/swine/Tianjin/1/04 maybe come from reassortments of classical H1N1 swine and H3N2 human viruses prevalent in North America.

  11. Influenza A Viruses of Human Origin in Swine, Brazil.

    Science.gov (United States)

    Nelson, Martha I; Schaefer, Rejane; Gava, Danielle; Cantão, Maurício Egídio; Ciacci-Zanella, Janice Reis

    2015-08-01

    The evolutionary origins of the influenza A(H1N1)pdm09 virus that caused the first outbreak of the 2009 pandemic in Mexico remain unclear, highlighting the lack of swine surveillance in Latin American countries. Although Brazil has one of the largest swine populations in the world, influenza was not thought to be endemic in Brazil's swine until the major outbreaks of influenza A(H1N1)pdm09 in 2009. Through phylogenetic analysis of whole-genome sequences of influenza viruses of the H1N1, H1N2, and H3N2 subtypes collected in swine in Brazil during 2009-2012, we identified multiple previously uncharacterized influenza viruses of human seasonal H1N2 and H3N2 virus origin that have circulated undetected in swine for more than a decade. Viral diversity has further increased in Brazil through reassortment between co-circulating viruses, including A(H1N1)pdm09. The circulation of multiple divergent hemagglutinin lineages challenges the design of effective cross-protective vaccines and highlights the need for additional surveillance.

  12. Influenza A Viruses of Human Origin in Swine, Brazil

    Science.gov (United States)

    Schaefer, Rejane; Gava, Danielle; Cantão, Maurício Egídio; Ciacci-Zanella, Janice Reis

    2015-01-01

    The evolutionary origins of the influenza A(H1N1)pdm09 virus that caused the first outbreak of the 2009 pandemic in Mexico remain unclear, highlighting the lack of swine surveillance in Latin American countries. Although Brazil has one of the largest swine populations in the world, influenza was not thought to be endemic in Brazil’s swine until the major outbreaks of influenza A(H1N1)pdm09 in 2009. Through phylogenetic analysis of whole-genome sequences of influenza viruses of the H1N1, H1N2, and H3N2 subtypes collected in swine in Brazil during 2009–2012, we identified multiple previously uncharacterized influenza viruses of human seasonal H1N2 and H3N2 virus origin that have circulated undetected in swine for more than a decade. Viral diversity has further increased in Brazil through reassortment between co-circulating viruses, including A(H1N1)pdm09. The circulation of multiple divergent hemagglutinin lineages challenges the design of effective cross-protective vaccines and highlights the need for additional surveillance. PMID:26196759

  13. Efficacy of influenza vaccination and tamiflu® treatment--comparative studies with Eurasian Swine influenza viruses in pigs.

    Science.gov (United States)

    Duerrwald, Ralf; Schlegel, Michael; Bauer, Katja; Vissiennon, Théophile; Wutzler, Peter; Schmidtke, Michaela

    2013-01-01

    Recent epidemiological developments demonstrated that gene segments of swine influenza A viruses can account for antigenic changes as well as reduced drug susceptibility of pandemic influenza A viruses. This raises questions about the efficacy of preventive measures against swine influenza A viruses. Here, the protective effect of vaccination was compared with that of prophylactic Tamiflu® treatment against two Eurasian swine influenza A viruses. 11-week-old pigs were infected by aerosol nebulisation with high doses of influenza virus A/swine/Potsdam/15/1981 (H1N1/1981, heterologous challenge to H1N1 vaccine strain) and A/swine/Bakum/1832/2000 (H1N2/2000, homologous challenge to H1N2 vaccine strain) in two independent trials. In each trial (i) 10 pigs were vaccinated twice with a trivalent vaccine (RESPIPORC® FLU3; 28 and 7 days before infection), (ii) another 10 pigs received 150 mg/day of Tamiflu® for 5 days starting 12 h before infection, and (iii) 12 virus-infected pigs were left unvaccinated and untreated and served as controls. Both viruses replicated efficiently in porcine respiratory organs causing influenza with fever, dyspnoea, and pneumonia. Tamiflu® treatment as well as vaccination prevented clinical signs and significantly reduced virus shedding. Whereas after homologous challenge with H1N2/2000 no infectious virus in lung and hardly any lung inflammation were detected, the virus titre was not and the lung pathology was only partially reduced in H1N1/1981, heterologous challenged pigs. Tamiflu® application did not affect these study parameters. In conclusion, all tested preventive measures provided protection against disease. Vaccination additionally prevented virus replication and histopathological changes in the lung of homologous challenged pigs.

  14. Efficacy of influenza vaccination and tamiflu® treatment--comparative studies with Eurasian Swine influenza viruses in pigs.

    Directory of Open Access Journals (Sweden)

    Ralf Duerrwald

    Full Text Available Recent epidemiological developments demonstrated that gene segments of swine influenza A viruses can account for antigenic changes as well as reduced drug susceptibility of pandemic influenza A viruses. This raises questions about the efficacy of preventive measures against swine influenza A viruses. Here, the protective effect of vaccination was compared with that of prophylactic Tamiflu® treatment against two Eurasian swine influenza A viruses. 11-week-old pigs were infected by aerosol nebulisation with high doses of influenza virus A/swine/Potsdam/15/1981 (H1N1/1981, heterologous challenge to H1N1 vaccine strain and A/swine/Bakum/1832/2000 (H1N2/2000, homologous challenge to H1N2 vaccine strain in two independent trials. In each trial (i 10 pigs were vaccinated twice with a trivalent vaccine (RESPIPORC® FLU3; 28 and 7 days before infection, (ii another 10 pigs received 150 mg/day of Tamiflu® for 5 days starting 12 h before infection, and (iii 12 virus-infected pigs were left unvaccinated and untreated and served as controls. Both viruses replicated efficiently in porcine respiratory organs causing influenza with fever, dyspnoea, and pneumonia. Tamiflu® treatment as well as vaccination prevented clinical signs and significantly reduced virus shedding. Whereas after homologous challenge with H1N2/2000 no infectious virus in lung and hardly any lung inflammation were detected, the virus titre was not and the lung pathology was only partially reduced in H1N1/1981, heterologous challenged pigs. Tamiflu® application did not affect these study parameters. In conclusion, all tested preventive measures provided protection against disease. Vaccination additionally prevented virus replication and histopathological changes in the lung of homologous challenged pigs.

  15. Efficacy of Influenza Vaccination and Tamiflu® Treatment – Comparative Studies with Eurasian Swine Influenza Viruses in Pigs

    Science.gov (United States)

    Duerrwald, Ralf; Schlegel, Michael; Bauer, Katja; Vissiennon, Théophile; Wutzler, Peter; Schmidtke, Michaela

    2013-01-01

    Recent epidemiological developments demonstrated that gene segments of swine influenza A viruses can account for antigenic changes as well as reduced drug susceptibility of pandemic influenza A viruses. This raises questions about the efficacy of preventive measures against swine influenza A viruses. Here, the protective effect of vaccination was compared with that of prophylactic Tamiflu® treatment against two Eurasian swine influenza A viruses. 11-week-old pigs were infected by aerosol nebulisation with high doses of influenza virus A/swine/Potsdam/15/1981 (H1N1/1981, heterologous challenge to H1N1 vaccine strain) and A/swine/Bakum/1832/2000 (H1N2/2000, homologous challenge to H1N2 vaccine strain) in two independent trials. In each trial (i) 10 pigs were vaccinated twice with a trivalent vaccine (RESPIPORC® FLU3; 28 and 7 days before infection), (ii) another 10 pigs received 150 mg/day of Tamiflu® for 5 days starting 12 h before infection, and (iii) 12 virus-infected pigs were left unvaccinated and untreated and served as controls. Both viruses replicated efficiently in porcine respiratory organs causing influenza with fever, dyspnoea, and pneumonia. Tamiflu® treatment as well as vaccination prevented clinical signs and significantly reduced virus shedding. Whereas after homologous challenge with H1N2/2000 no infectious virus in lung and hardly any lung inflammation were detected, the virus titre was not and the lung pathology was only partially reduced in H1N1/1981, heterologous challenged pigs. Tamiflu® application did not affect these study parameters. In conclusion, all tested preventive measures provided protection against disease. Vaccination additionally prevented virus replication and histopathological changes in the lung of homologous challenged pigs. PMID:23630601

  16. Swine Influenza Virus Antibodies in Humans, Western Europe, 2009

    Science.gov (United States)

    Gerloff, Nancy A.; Kremer, Jacques R.; Charpentier, Emilie; Sausy, Aurélie; Olinger, Christophe M.; Weicherding, Pierre; Schuh, John; Van Reeth, Kristien

    2011-01-01

    Serologic studies for swine influenza viruses (SIVs) in humans with occupational exposure to swine have been reported from the Americas but not from Europe. We compared levels of neutralizing antibodies against 3 influenza viruses—pandemic (H1N1) 2009, an avian-like enzootic subtype H1N1 SIV, and a 2007–08 seasonal subtype H1N1—in 211 persons with swine contact and 224 matched controls in Luxembourg. Persons whose profession involved contact with swine had more neutralizing antibodies against SIV and pandemic (H1N1) 2009 virus than did the controls. Controls also had antibodies against these viruses although exposure to them was unlikely. Antibodies against SIV and pandemic (H1N1) 2009 virus correlated with each other but not with seasonal subtype H1N1 virus. Sequential exposure to variants of seasonal influenza (H1N1) viruses may have increased chances for serologic cross-reactivity with antigenically distinct viruses. Further studies are needed to determine the extent to which serologic responses correlate with infection. PMID:21392430

  17. Assessing the Risk of African Swine Fever Introduction into the European Union by Wild Boar.

    Science.gov (United States)

    De la Torre, A; Bosch, J; Iglesias, I; Muñoz, M J; Mur, L; Martínez-López, B; Martínez, M; Sánchez-Vizcaíno, J M

    2015-06-01

    The presence of African swine fever (ASF) in the Caucasus region and Russian Federation has increased concerns that wild boars may introduce the ASF virus into the European Union (EU). This study describes a semi-quantitative approach for evaluating the risk of ASF introduction into the EU by wild boar movements based on the following risk estimators: the susceptible population of (1) wild boars and (2) domestic pigs in the country of origin; the outbreak density in (3) wild boars and (4) domestic pigs in the countries of origin, the (5) suitable habitat for wild boars along the EU border; and the distance between the EU border and the nearest ASF outbreak in (6) wild boars or (7) domestic pigs. Sensitivity analysis was performed to identify the most influential risk estimators. The highest risk was found to be concentrated in Finland, Romania, Latvia and Poland, and wild boar habitat and outbreak density were the two most important risk estimators. Animal health authorities in at-risk countries should be aware of these risk estimators and should communicate closely with wild boar hunters and pig farmers to rapidly detect and control ASF. © 2013 Blackwell Verlag GmbH.

  18. Field and Experimental Investigations of an Outbreak of African Swine Fever in Nigeria

    Directory of Open Access Journals (Sweden)

    E. B. Otesile

    2005-01-01

    Full Text Available An outbreak of African Swine Fever (ASF, characterized by a mortality of 50 to 100% in various herds, was diagnosed among free-ranging domesticated pigs in Delta State, Nigeria, in August 1998. The etiological confirmation of ASF was made by virus isolation, PCR and sequencing of a 280 base pair fragment of the major capsid protein (VP72 gene. Experimental infection of pigs with infected blood resulted in pyrexia, which peaked two to four days postinfection, followed by death in five to six days postinfection. Postmortem examination revealed widespread hemorrhage, congestion and edema of tissues. The lymph nodes, spleen, liver and kidneys showed marked focal random necrosis and loss of lymphocytes from the splenic and lymphoid follicles. There was an acute orchitis with massive neutrophilic and macrophage infiltrates into the intertubular connective tissue. Meningitis and focal hemorrhages were observed in the brain and spinal cord. The outbreak was believed to be a continuation of an eastward spread of ASF from neighboring Benin, which began the previous year (1997.

  19. Comparison of sampling techniques for Rift Valley Fever virus ...

    African Journals Online (AJOL)

    time for trapping potential vectors for Rift Valley Fever virus. ..... Krockel, U., Rose, A., Eiras, A.E. & Geier, M. (2006) New tools for surveillance of adult yellow fever ... baited trapping systems for sampling outdoor mosquito populations in ...

  20. [The eradication of African swine fever in Brazil, 1978-1984].

    Science.gov (United States)

    Lyra, T M P

    2006-04-01

    The African swine fever episode in Brazil was due to trade and tourism between Spain, Portugal and Brazil, at a time when outbreaks were on the rise in Europe. The eradication of the disease, the slaughter of pigs, the elimination of the carcasses and the isolation of affected farms were given wide media coverage, and had a major socio-economic impact. It was forbidden to raise pigs in garbage dumps or to give them feed considered hazardous. Analyses performed in Brazil as well as national and international investigations by researchers from reference laboratories concluded that the disease had spread from Rio de Janeiro to other states, as is stated in official reports. Following emergency measures, a control programme was implemented, leading to enhanced quality in the pig farming sector. The authors describe epidemiological surveillance of African swine fever, classical swine fever and related diseases, biosafety in swine farming, and the emergency action plan comprising animal health training for veterinarians and social workers. The results of the eradication programme were excellent, despite the controversy over compulsory sacrifice in a country with serious social problems. In 2004, Brazil was the fourth largest pork producer and exporter, with an output of 2.679 million tons and exports of 508,000 tons to international markets with very high standards.

  1. Prospective surveillance for influenza. virus in Chinese swine farms.

    Science.gov (United States)

    Anderson, Benjamin D; Ma, Mai-Juan; Wang, Guo-Lin; Bi, Zhen-Qiang; Lu, Bing; Wang, Xian-Jun; Wang, Chuang-Xin; Chen, Shan-Hui; Qian, Yan-Hua; Song, Shao-Xia; Li, Min; Zhao, Teng; Wu, Meng-Na; Borkenhagen, Laura K; Cao, Wu-Chun; Gray, Gregory C

    2018-05-16

    Pork production in China is rapidly increasing and swine production operations are expanding in size and number. However, the biosecurity measures necessary to prevent swine disease transmission, particularly influenza. viruses (IAV) that can be zoonotic, are often inadequate. Despite this risk, few studies have attempted to comprehensively study IAV ecology in swine production settings. Here, we present environmental and animal sampling data collected in the first year of an ongoing five-year prospective epidemiological study to assess IAV ecology as it relates to swine workers, their pigs, and the farm environment. From March 2015 to February 2016, we collected 396 each of environmental swab, water, bioaerosol, and fecal/slurry samples, as well as 3300 pig oral secretion samples from six farms in China. The specimens were tested with molecular assays for IAV. Of these, 46 (11.6%) environmental swab, 235 (7.1%) pig oral secretion, 23 (5.8%) water, 20 (5.1%) bioaerosol, and 19 (4.8%) fecal/slurry specimens were positive for influenza. by qRT-PCR. Risk factors for IAV detection among collected samples were identified using bivariate logistic regression. Overall, these first year data suggest that IAV is quite ubiquitous in the swine production environment and demonstrate an association between the different types of environmental sampling used. Given the mounting evidence that some of these viruses freely move between pigs and swine workers, and that mixing of these viruses can yield progeny viruses with pandemic potential, it seems imperative that routine surveillance for novel IAVs be conducted in commercial swine farms.

  2. Hepatitis E Virus Genotype 3 in Humans and Swine, Bolivia

    Science.gov (United States)

    Cavallo, Annalisa; Gonzales, José Luis; Bonelli, Sara Irene; Valda, Ybar; Pieri, Angela; Segundo, Higinio; Ibañez, Ramón; Mantella, Antonia; Bartalesi, Filippo; Tolari, Francesco; Bartoloni, Alessandro

    2011-01-01

    We determined the seroprevalence of hepatitis E virus (HEV) in persons in 2 rural communities in southeastern Bolivia and the presence of HEV in human and swine fecal samples. HEV seroprevalence was 6.3%, and HEV genotype 3 strains with high sequence homology were detected. PMID:21801630

  3. Efficacy of Influenza Vaccination and Tamiflu? Treatment ? Comparative Studies with Eurasian Swine Influenza Viruses in Pigs

    OpenAIRE

    Duerrwald, Ralf; Schlegel, Michael; Bauer, Katja; Vissiennon, Th?ophile; Wutzler, Peter; Schmidtke, Michaela

    2013-01-01

    Recent epidemiological developments demonstrated that gene segments of swine influenza A viruses can account for antigenic changes as well as reduced drug susceptibility of pandemic influenza A viruses. This raises questions about the efficacy of preventive measures against swine influenza A viruses. Here, the protective effect of vaccination was compared with that of prophylactic Tamiflu® treatment against two Eurasian swine influenza A viruses. 11-week-old pigs were infected by aerosol nebu...

  4. Interventions Against West Nile Virus, Rift Valley Fever Virus, and Crimean-Congo Hemorrhagic Fever Virus: Where Are We?

    NARCIS (Netherlands)

    Kortekaas, J.A.; Ergonul, O.; Moormann, R.J.M.

    2010-01-01

    ARBO-ZOONET is an international network financed by the European Commission's seventh framework program. The major goal of this initiative is capacity building for the control of emerging viral vector-borne zoonotic diseases, with a clear focus on West Nile virus, Rift Valley fever virus, and

  5. Preventive vaccination contributes to control classical swine fever in wild boar (Sus scrofa sp.).

    Science.gov (United States)

    Rossi, S; Pol, F; Forot, B; Masse-Provin, N; Rigaux, S; Bronner, A; Le Potier, M-F

    2010-04-21

    Over the last 20 years, oral vaccination implementing a live attenuated vaccine has been experimented in Europe in order to control classical swine fever (CSF) in Wild Boar (Sus scrofa sp.). This has generally led to an enhanced seroprevalence and a decreased viroprevalence at the scale of the whole vaccinated populations, but no quantitative analysis has demonstrated the protective effect of preventive vaccination or intensive baiting. In the present paper we conducted a retrospective analysis at the scale of the municipality, taking into account the local dynamics and possible covariates of infection to test the effect of preventive vaccination and of the baiting effort. To be efficient, vaccination was expected to increase seroprevalence above the level considered as suitable for preventing disease invasion (40-60%) independently of infection, to protect free areas from disease invasion or contribute to control subsequent disease intensity and duration. We also hypothesized that a better baiting effort would be correlated with an improvement of immunisation and disease control. In uninfected municipalities, seroprevalence increased up to 40% after 1 year, i.e., three vaccination campaigns. We observed a significant protective effect of preventive vaccination, especially within municipalities that had been vaccinated at least 1 year before disease emergence and where virus detection did not last more than one quarter. On the other hand, we did not detect a significant effect of the baiting effort on local seroprevalence or disease dynamics, suggesting that the baiting system could be improved. We discuss these results regarding the improvement of management measures and further research perspective. Copyright 2009 Elsevier B.V. All rights reserved.

  6. A multiplex reverse transcription PCR and automated electronic microarray assay for detection and differentiation of seven viruses affecting swine.

    Science.gov (United States)

    Erickson, A; Fisher, M; Furukawa-Stoffer, T; Ambagala, A; Hodko, D; Pasick, J; King, D P; Nfon, C; Ortega Polo, R; Lung, O

    2018-04-01

    Microarray technology can be useful for pathogen detection as it allows simultaneous interrogation of the presence or absence of a large number of genetic signatures. However, most microarray assays are labour-intensive and time-consuming to perform. This study describes the development and initial evaluation of a multiplex reverse transcription (RT)-PCR and novel accompanying automated electronic microarray assay for simultaneous detection and differentiation of seven important viruses that affect swine (foot-and-mouth disease virus [FMDV], swine vesicular disease virus [SVDV], vesicular exanthema of swine virus [VESV], African swine fever virus [ASFV], classical swine fever virus [CSFV], porcine respiratory and reproductive syndrome virus [PRRSV] and porcine circovirus type 2 [PCV2]). The novel electronic microarray assay utilizes a single, user-friendly instrument that integrates and automates capture probe printing, hybridization, washing and reporting on a disposable electronic microarray cartridge with 400 features. This assay accurately detected and identified a total of 68 isolates of the seven targeted virus species including 23 samples of FMDV, representing all seven serotypes, and 10 CSFV strains, representing all three genotypes. The assay successfully detected viruses in clinical samples from the field, experimentally infected animals (as early as 1 day post-infection (dpi) for FMDV and SVDV, 4 dpi for ASFV, 5 dpi for CSFV), as well as in biological material that were spiked with target viruses. The limit of detection was 10 copies/μl for ASFV, PCV2 and PRRSV, 100 copies/μl for SVDV, CSFV, VESV and 1,000 copies/μl for FMDV. The electronic microarray component had reduced analytical sensitivity for several of the target viruses when compared with the multiplex RT-PCR. The integration of capture probe printing allows custom onsite array printing as needed, while electrophoretically driven hybridization generates results faster than conventional

  7. Swine influenza viruses isolated in 1983, 2002 and 2009 in Sweden exemplify different lineages

    Directory of Open Access Journals (Sweden)

    Metreveli Giorgi

    2010-12-01

    Full Text Available Abstract Swine influenza virus isolates originating from outbreaks in Sweden from 1983, 2002 and 2009 were subjected to nucleotide sequencing and phylogenetic analysis. The aim of the studies was to obtain an overview on their potential relatedness as well as to provide data for broader scale studies on swine influenza epidemiology. Nonetheless, analyzing archive isolates is justified by the efforts directed to the comprehension of the appearance of pandemic H1N1 influenza virus. Interestingly, this study illustrates the evolution of swine influenza viruses in Europe, because the earliest isolate belonged to 'classical' swine H1N1, the subsequent ones to Eurasian 'avian-like' swine H1N1 and reassortant 'avian-like' swine H1N2 lineages, respectively. The latter two showed close genetic relatedness regarding their PB2, HA, NP, and NS genes, suggesting common ancestry. The study substantiates the importance of molecular surveillance for swine influenza viruses.

  8. The Epidemiology of African Swine Fever in "Nonendemic" Regions of Zambia (1989-2015): Implications for Disease Prevention and Control.

    Science.gov (United States)

    Simulundu, Edgar; Lubaba, Caesar H; van Heerden, Juanita; Kajihara, Masahiro; Mataa, Liywalii; Chambaro, Herman Moses; Sinkala, Yona; Munjita, Samuel Munalula; Munang'andu, Hetron Mweemba; Nalubamba, King Shimumbo; Samui, Kenny; Pandey, Girja Shanker; Takada, Ayato; Mweene, Aaron S

    2017-08-23

    African swine fever (ASF) is a highly contagious and deadly viral hemorrhagic disease of swine. In Zambia, ASF was first reported in 1912 in Eastern Province and is currently believed to be endemic in that province only. Strict quarantine measures implemented at the Luangwa River Bridge, the only surface outlet from Eastern Province, appeared to be successful in restricting the disease. However, in 1989, an outbreak occurred for the first time outside the endemic province. Sporadic outbreaks have since occurred almost throughout the country. These events have brought into acute focus our limited understanding of the epidemiology of ASF in Zambia. Here, we review the epidemiology of the disease in areas considered nonendemic from 1989 to 2015. Comprehensive sequence analysis conducted on genetic data of ASF viruses (ASFVs) detected in domestic pigs revealed that p72 genotypes I, II, VIII and XIV have been involved in causing ASF outbreaks in swine during the study period. With the exception of the 1989 outbreak, we found no concrete evidence of dissemination of ASFVs from Eastern Province to other parts of the country. Our analyses revealed a complex epidemiology of the disease with a possibility of sylvatic cycle involvement. Trade and/or movement of pigs and their products, both within and across international borders, appear to have been the major factor in ASFV dissemination. Since ASFVs with the potential to cause countrywide and possibly regional outbreaks, could emerge from "nonendemic regions", the current ASF control policy in Zambia requires a dramatic shift to ensure a more sustainable pig industry.

  9. Molucular Epidemiology and Evolution of Influenza Viruses Circulating within European Swine between 2009 and 2013

    NARCIS (Netherlands)

    Watson, S.J.; Langat, P.; Reid, S.; Lam, T.; Cotten, M.; Kelly, M.; Reeth, Van K.; Qiu, Y.; Simon, G.; Bonin, E.; Foni, E.; Chiapponi, C.; Larsen, L.; Hjulsager, C.; Markowska-Daniel, I.; Urbaniak, K.; Durrwald, R.; Schlegel, M.; Huovilainen, A.; Davidson, I.; Dan, A.; Loeffen, W.L.A.; Edwards, S.; Bublot, M.; Vila, T.; Maldonado, J.; Valls, L.; Brown, I.H.; Pybus, O.G.; Kellam, P.

    2015-01-01

    The emergence in humans of the A(H1N1)pdm09 influenza virus, a complex reassortant virus of swine origin, highlighted the importance of worldwide influenza virus surveillance in swine. To date, large-scale surveillance studies have been reported for southern China and North America, but such data

  10. Electron microscopic identification of Zinga virus as a strain of Rift Valley fever virus.

    Science.gov (United States)

    Olaleye, O D; Baigent, C L; Mueller, G; Tomori, O; Schmitz, H

    1992-01-01

    Electron microscopic examination of a negatively stained suspension of Zinga virus showed particles 90-100 nm in diameter, enveloped with spikes 12-20 nm in length and 5 nm in diameter. Further identification of the virus by immune electron microscopy showed the reactivity of human Rift Valley fever virus-positive serum with Zinga virus. Results of this study are in agreement with earlier reports that Zinga virus is a strain of Rift Valley fever virus.

  11. Emergency vaccination for classical swine fever will not be cost-effective for countries with a large export

    DEFF Research Database (Denmark)

    Boklund, Anette; Toft, Nils; Alban, Lis

    2009-01-01

    the epidemiological and economic consequences of such control strategies under Danish conditions with respect to herd demographics and geography as well as to investigate the effect of extra biosecurity on farms. We used InterSpread Plus to model the effect of nine different control strategies: the minimum measures......,H.M., Smak,J.A., Pluimers,F.H., 1999. The classical swine fever epidemic 1997-1998 in The Netherlands: descriptive epidemiology, Prev.Vet.Med., 42, 157-184. Fritzemeier,J., Teuffert,J., Greiser,Wilke,I, Staubach,Ch, Schlüter,H., Moennig,V., 2000. Epidemiology of classical swine fever in Germany in the 1990s......, Vet.Microbiol. 77, 29-41. MacKinnon, J.D., 2001. Some clinical and epidemiological aspects of the outbreak of Classical Swine Fe-ver in East Anglia in 2000, State Vet.J,, 11, 2-7....

  12. Phylogeny of Yellow Fever Virus, Uganda, 2016.

    Science.gov (United States)

    Hughes, Holly R; Kayiwa, John; Mossel, Eric C; Lutwama, Julius; Staples, J Erin; Lambert, Amy J

    2018-08-17

    In April 2016, a yellow fever outbreak was detected in Uganda. Removal of contaminating ribosomal RNA in a clinical sample improved the sensitivity of next-generation sequencing. Molecular analyses determined the Uganda yellow fever outbreak was distinct from the concurrent yellow fever outbreak in Angola, improving our understanding of yellow fever epidemiology.

  13. Comparing the epidemiological and economic effects of control strategies against classical swine fever in Denmark

    DEFF Research Database (Denmark)

    Boklund, Anette; Toft, Nils; Alban, Lis

    2009-01-01

    In 2006, total Danish pork exports were valued at (sic)3.8 billion, corresponding to approximately 5% of the total Danish exports, and an outbreak of a notifiable disease would have dramatic consequences for the agricultural sector in Denmark. Several outbreaks of classical swine fever (CSF) have...... occurred in Europe within the last decade, and different control strategies have been suggested. The objective of this study was to simulate the epidemiological and economic consequences of such control strategies in a CSF epidemic under Danish conditions with respect to herd demographics and geography...

  14. Expert groups in Denmark with special reference to Classical and African swine fever

    DEFF Research Database (Denmark)

    Uttenthal, Åse

    2012-01-01

    surveillance, in Contingency planning exercises and many efforts is done to keep the group updated on the current international situation for swine fevers. The group has been very stabile and especially our participation in a Taiex workshop in 2005 in Romania was a very good basis for our fruitful...... collaboration. In many later discussions our experiences then when we observed the problems in vivo. The obligations of the expert group are both to follow the progress of eradication but definitely also to take care of some of the more time consuming discussions that could otherwise burden the Veterinary...

  15. Early protection events in swine immunized with an experimental live attenuated classical swine fever marker vaccine, FlagT4G.

    Directory of Open Access Journals (Sweden)

    Lauren G Holinka

    Full Text Available Prophylactic vaccination using live attenuated classical swine fever (CSF vaccines has been a very effective method to control the disease in endemic regions and during outbreaks in previously disease-free areas. These vaccines confer effective protection against the disease at early times post-vaccination although the mechanisms mediating the protection are poorly characterized. Here we present the events occurring after the administration of our in-house developed live attenuated marker vaccine, FlagT4Gv. We previously reported that FlagT4Gv intramuscular (IM administered conferred effective protection against intranasal challenge with virulent CSFV (BICv as early as 7 days post-vaccination. Here we report that FlagT4Gv is able to induce protection against disease as early as three days post-vaccination. Immunohistochemical testing of tissues from FlagT4Gv-inoculated animals showed that tonsils were colonized by the vaccine virus by day 3 post-inoculation. There was a complete absence of BICv in tonsils of FlagT4Gv-inoculated animals which had been intranasal (IN challenged with BICv 3 days after FlagT4Gv infection, confirming that FlagT4Gv inoculation confers sterile immunity. Analysis of systemic levels of 19 different cytokines in vaccinated animals demonstrated an increase of IFN-α three days after FlagT4Gv inoculation compared with mock infected controls.

  16. STUDIES ON THE PATHOGENESIS OF FEVER WITH INFLUENZAL VIRUSES

    Science.gov (United States)

    Atkins, Elisha; Huang, Wei Cheng

    1958-01-01

    A substance with pyrogenic properties appears in the blood streams of rabbits made febrile by the intravenous inoculation of the PR8 strain of influenza A and Newcastle disease viruses (NDV). By means of a technique involving passive transfer of sera from animals given virus to recipient rabbits, the titer of circulating pyrogen was found to be closely correlated with the course of fever produced by virus. Certain properties of the pyrogen are described which differentiate it from the originally injected virus and suggest that the induced pyrogen is of endogenous origin. These properties resemble those of endogenous pyrogens occurring in other forms of experimental fever. The source of virus-induced pyrogen is unknown. In vitro incubation of virus with various constituents of the circulation did not result in the appearance of endogenous pyrogen. Granulocytopenia induced by HN2 failed to influence either fever or the production of endogenous pyrogen in rabbits injected with NDV. Similarly, the intraperitoneal inoculation of NDV into prepared exudates did not modify the febrile response. These findings do not lend support to the possibility that the polymorphonuclear leukocyte is a significant source of endogenous pyrogen in virus-induced fever. It is concluded that the liberation of an endogenous pyrogen from some as yet undefined source is an essential step in the pathogenesis of fever caused by the influenza group of viruses. PMID:13513908

  17. Swine flu

    Directory of Open Access Journals (Sweden)

    Manish Sinha

    Full Text Available Summary: The recent outbreak of human infection with a novel Swine-Origin Influenza A (H1N1 virus is spreading rapidly through sustained human-to-human transmission in multiple countries. Human-to-human transmission occurs by inhalation of infectious droplets and droplet nuclei, and by direct contact, which is facilitated by air and land travel and social gatherings. The most frequently reported symptoms are fever, cough, myalgia, and sore throat. Detailed contact and travel histories and knowledge of viral activity in community are essential for prompt case detection by the health personnel. Real-time Reverse Transcriptase-Polymerase Chain Reaction analysis of throat swabs or lower respiratory samples is a sensitive means of diagnosis. Use of oral oseltamivir may be warranted for the treatment of severe illness. Keywords: Swine influenza, H1N1, Swine flu, Oseltamivir

  18. Inactivation of Viruses and Bacteriophages as Models for Swine Hepatitis E Virus in Food Matrices.

    Science.gov (United States)

    Emmoth, Eva; Rovira, Jordi; Rajkovic, Andreja; Corcuera, Elena; Wilches Pérez, Diego; Dergel, Irene; Ottoson, Jakob R; Widén, Frederik

    2017-03-01

    Hepatitis E virus has been recognised as a food-borne virus hazard in pork products, due to its zoonotic properties. This risk can be reduced by adequate treatment of the food to inactivate food-borne viruses. We used a spectrum of viruses and bacteriophages to evaluate the effect of three food treatments: high pressure processing (HPP), lactic acid (LA) and intense light pulse (ILP) treatments. On swine liver at 400 MPa for 10 min, HPP gave log 10 reductions of ≥4.2, ≥5.0 and 3.4 for feline calicivirus (FCV) 2280, FCV wildtype (wt) and murine norovirus 1 (MNV 1), respectively. Escherichia coli coliphage ϕX174 displayed a lower reduction of 1.1, while Escherichia coli coliphage MS2 was unaffected. For ham at 600 MPa, the corresponding reductions were 4.1, 4.4, 2.9, 1.7 and 1.3 log 10 . LA treatment at 2.2 M gave log 10 reductions in the viral spectrum of 0.29-2.1 for swine liver and 0.87-3.1 for ham, with ϕX174 and MNV 1, respectively, as the most stable microorganisms. The ILP treatment gave log 10 reductions of 1.6-2.8 for swine liver, 0.97-2.2 for ham and 1.3-2.3 for sausage, at 15-60 J cm -2 , with MS2 as the most stable microorganism. The HPP treatment gave significantly (p virus reduction on swine liver than ham for the viruses at equivalent pressure/time combinations. For ILP treatment, reductions on swine liver were significantly (p virus contamination and in advice to food producers. Conservative model indicators for the pathogenic viruses could be suggested.

  19. Genetic Reassortment Among the Influenza Viruses (Avian Influenza, Human Influenza and Swine Influenza in Pigs

    Directory of Open Access Journals (Sweden)

    Dyah Ayu Hewajuli

    2012-12-01

    Full Text Available Influenza A virus is a hazardous virus and harm to respiratory tract. The virus infect birds, pigs, horses, dogs, mammals and humans. Pigs are important hosts in ecology of the influenza virus because they have two receptors, namely NeuAc 2,3Gal and NeuAc 2,6Gal which make the pigs are sensitive to infection of influenza virus from birds and humans and genetic reassortment can be occurred. Classical swine influenza H1N1 viruses had been circulated in pigs in North America and other countries for 80 years. In 1998, triple reassortant H3N2 swine influenza viruses that contains genes of human influenza A virus (H3N2, swine influenza virus (H1N1 and avian influenza are reported as cause an outbreaks in pigs in North America. Furthermore, the circulation of triple reassortant H3N2 swine influenza virus resulting reassortant H1N1 swine influenza and reassortant H1N2 swine influenza viruses cause infection in humans. Humans who were infected by triple reassortant swine influenza A virus (H1N1 usually made direct contact with pigs. Although without any clinical symptoms, pigs that are infected by triple reassortant swine influenza A (H1N1 can transmit infection to the humans around them. In June 2009, WHO declared that pandemic influenza of reassortant H1N1 influenza A virus (novel H1N1 has reached phase 6. In Indonesia until 2009, there were 1005 people were infected by H1N1 influenza A and 5 of them died. Novel H1N1 and H5N1 viruses have been circulated in humans and pigs in Indonesia. H5N1 reassortant and H1N1 viruses or the seasonal flu may could arise because of genetic reassortment between avian influenza and humans influenza viruses that infect pigs together.

  20. Seroprevalence and risk factors for the presence of ruminant pestviruses in the Dutch swine population

    NARCIS (Netherlands)

    Loeffen, W.L.A.; Beuningen, van A.R.; Quak, J.; Elbers, A.R.W.

    2009-01-01

    Swine can be infected with classical swine fever virus (CSFV), as well as ruminant pestiviruses: bovine viral diarrhoea virus (BVDV), and Border disease virus (BDV). Cross-reactions between pestiviruses occur, both regarding protective immunity and in diagnostic tests. The presence of BVDV and BDV

  1. High IFN-alpha responses associated with depletion of lymphocytes and natural IFN-producing cells during classical swine fever

    NARCIS (Netherlands)

    Summerfield, A.; Alves, M.; Ruggli, N.; Bruin, de M.G.M.; McCullough, K.C.

    2006-01-01

    During the acute phase of the viral hemorrhagic disease, classical swine fever (CSF), a severe hematologic depletion in primary lymphoid organs and depletion of peripheral blood T and B lymphocytes are observed. The onset of these pathologic events is before viremia and independent of leukocyte

  2. Simulated epidemiological and economic effects of measures to reduce piglet supply during a classical swine fever epidemic in the Netherlands

    NARCIS (Netherlands)

    Mangen, M.J.J.; Nielen, M.; Burrell, A.M.

    2003-01-01

    The effects of additional measures adopted during a classical swine fever (CSF) epidemic to reduce piglet supply, namely, an insemination ban, abortion of sows and killing of young piglets, are studied using a stochastic, spatial, dynamic epidemiological simulation model of the pig sector in the

  3. Strategies for differentiating infection in vaccinated animals (DIVA) for foot-and-mouth disease, classical swine fever and avian influenza

    DEFF Research Database (Denmark)

    Uttenthal, Åse; Parida, Satya; Rasmussen, Thomas Bruun

    2010-01-01

    for the presence of infection. This literature review describes the current knowledge on the use of DIVA diagnostic strategies for three important transboundary animal diseases: foot-and-mouth disease in cloven-hoofed animals, classical swine fever in pigs and avian influenza in poultry....

  4. Cross border Classical Swine Fever control: Improving Dutch and German crisis management systems by an integrated public-private approach

    NARCIS (Netherlands)

    Breuer, O.; Saatkamp, H.W.; Schütz, V.; Brinkmann, D.; Petersen, B.

    2008-01-01

    The objective of this research approach is to analyse in which ways crisis management measures against Classical Swine Fever (CSF) can be improved by a public private cross border model. A core activity contains the analysis of information and communication systems: In a case study it has been

  5. Introduction of African swine fever into the European Union through illegal importation of pork and pork products.

    Science.gov (United States)

    Costard, Solenne; Jones, Bryony Anne; Martínez-López, Beatriz; Mur, Lina; de la Torre, Ana; Martínez, Marta; Sánchez-Vizcaíno, Fernando; Sánchez-Vizcaíno, Jose-Manuel; Pfeiffer, Dirk Udo; Wieland, Barbara

    2013-01-01

    Transboundary animal diseases can have very severe socio-economic impacts when introduced into new regions. The history of disease incursions into the European Union suggests that initial outbreaks were often initiated by illegal importation of meat and derived products. The European Union would benefit from decision-support tools to evaluate the risk of disease introduction caused by illegal imports in order to inform its surveillance strategy. However, due to the difficulty in quantifying illegal movements of animal products, very few studies of this type have been conducted. Using African swine fever as an example, this work presents a novel risk assessment framework for disease introduction into the European Union through illegal importation of meat and products. It uses a semi-quantitative approach based on factors that likely influence the likelihood of release of contaminated smuggled meat and products, and subsequent exposure of the susceptible population. The results suggest that the European Union is at non-negligible risk of African swine fever introduction through illegal importation of pork and products. On a relative risk scale with six categories from negligible to very high, five European Union countries were estimated at high (France, Germany, Italy and United Kingdom) or moderate (Spain) risk of African swine fever release, five countries were at high risk of exposure if African swine fever were released (France, Italy, Poland, Romania and Spain) and ten countries had a moderate exposure risk (Austria, Bulgaria, Germany, Greece, Hungary, Latvia, Lithuania, Portugal, Sweden and United Kingdom). The approach presented here and results obtained for African swine fever provide a basis for the enhancement of risk-based surveillance systems and disease prevention programmes in the European Union.

  6. Effect of radiation on certain animal viruses in liquid swine manure

    Energy Technology Data Exchange (ETDEWEB)

    Simon, J.; Mocsari, E.; di Gleria, M.; Felkai, V. (Phylaxia Oltoanyag- es Tapszertermeloe Vallalat, Budapest (Hungary); Orszagos Allategeszseguegyi Intezet, Budapest (Hungary))

    1983-03-01

    The virucidal effect of /sup 60/Co gamma radiation was studied in cell culture medium and in liquid swine manure involving the most important porcine viruses that can be spread by liquid manure. The radiation doses (20 kGy and 30 kGy) were determined in preliminary experiments employing a porcine enterovirus from the serogroup 1 (Teschen group). In the main experiment, the following viruses were employed: swine vesicular disease (SVD) virus, type C foot-and-mouth disease (FMD) virus, a field strain of Aujeszky's disease (AD) virus, transmissible gastroenteritis (TGE) virus, as well as bovine viral diarrhea (BVD) virus. The latter strain served as a model for hog cholera virus. The results of the experiments indicate that safe disinfection of the virus infected liquid swine manure by ionizing radiation requires a radiation dose of 30 kGy.

  7. Effect of radiation on certain animal viruses in liquid swine manure

    International Nuclear Information System (INIS)

    Simon, J.; Mocsari, E.; di Gleria, M.; Felkai, V.

    1983-01-01

    The virucidal effect of 60 Co gamma radiation was studied in cell culture medium and in liquid swine manure involving the most important porcine viruses that can be spread by liquid manure. The radiation doses (20 kGy and 30 kGy) were determined in preliminary experiments employing a porcine enterovirus from the serogroup 1 (Teschen group). In the main experiment, the following viruses were employed: swine vesicular disease (SVD) virus, type C foot-and-mouth disease (FMD) virus, a field strain of Aujeszky's disease (AD) virus, transmissible gastroenteritis (TGE) virus, as well as bovine viral diarrhoea (BVD) virus. The latter strain served as a model for hog cholera virus. The results of the experiments indicate that safe disinfection of the virus infected liquid swine manure by ionizing radiation requires a radiation dose of 30 kGy. (author)

  8. Effect of radiation on certain animal viruses in liquid swine manure

    Energy Technology Data Exchange (ETDEWEB)

    Simon, J; Mocsari, E; di Gleria, M; Felkai, V [Phylaxia Oltoanyag- es Tapszertermeloe Vallalat, Budapest (Hungary); Orszagos Allategeszseguegyi Intezet, Budapest [Hungary

    1983-03-01

    The virucidal effect of /sup 60/Co gamma radiation was studied in cell culture medium and in liquid swine manure involving the most important porcine viruses that can be spread by liquid manure. The radiation doses (20 kGy and 30 kGy) were determined in preliminary experiments employing a porcine enterovirus from the serogroup 1 (Teschen group). In the main experiment, the following viruses were employed: swine vesicular disease (SVD) virus, type C foot-and-mouth disease (FMD) virus, a field strain of Aujeszky's disease (AD) virus, transmissible gastroenteritis (TGE) virus, as well as bovine viral diarrhea (BVD) virus. The latter strain served as a model for hog cholera virus. The results of the experiments indicate that safe disinfection of the virus infected liquid swine manure by ionizing radiation requires a radiation dose of 30 kGy.

  9. MANAGEMENT PATIENT OF SWINE INFLUENZA

    Directory of Open Access Journals (Sweden)

    Endra Gunawan

    2015-05-01

    Full Text Available Influenza is an acute respiratory diseases caused by various influenza virus which infect the upper and lower respiratory tract and often accompanied by systemic symptoms such as fever, headache and muscle pain. Influenza spreads through the air. Swine influenza comes from swine and can cause an outbreaks in pig flocks. Even this is a kind of a rare case but the swine influenza could be transmitted to human by direct contact with infected swine or through environment that already being contaminated by swine influenza virus. There are 3 types of swine influenza virus namely H1N1, H3N2 and H1N2. Type H1N1 swine-virus had been known since 1918. Avian influenza virus infection is transmitted from one person to another through secret containing virus. Virus is binded into the mucous cells of respiratory tract before it is finally infecting the cells itself. Management patients with H1N1 influenza is based on the complications and the risk. Besides, it is also need to consider the clinical criteria of the patient. Therapy medicamentosa is applied to the patients by giving an antiviral, antibiotics and symptomatic therapy. Prevention can be done by avoid contact with infected animal or environment, having antiviral prophylaxis and vaccination.

  10. Situation of classical swine fever and the epidemiologic and ecologic aspects affecting its distribution in the American continent.

    Science.gov (United States)

    Vargas Terán, Moisés; Calcagno Ferrat, Nelson; Lubroth, Juan

    2004-10-01

    Classical swine fever (CSF) is a viral transboundary animal disease that is highly contagious among domestic and wild pigs, such as boars and peccaries. Today, far from being what was classically described historically, the disease is characterized as having a varied clinical picture, and its diagnosis depends on resorting to proper sample collection and prompt dispatch to a laboratory that can employ several techniques to obtain a definitive diagnosis. Laboratory findings should be complemented with a field analysis of the occurrence of disease to have a better understanding of its epidemiology. The disease is still present in various regions and countries of Latin America and the Caribbean, thus hindering production, trade, and the livestock economy in the region. Consequently, it is among the diseases included in List A of the Office International des Epizooties (OIE). Currently, there are epidemiologic and ecologic aspects that characterize its geographical distribution in the region such as: continued trends in the demand for pork and pork products; an increase in swine investment with low production costs which are able to compete advantageously in international markets; the convention of associating CSF in the syndrome of "swine hemorrhagic diseases" owing to the historical description of its acute presentation and not to the new and more frequent subacute presentations or the diseases with which it may be confused (notably, porcine reproductive and respiratory syndrome and porcine dermopathic nephropathy syndrome, among others); dissemination of the virus through asymptomatic hosts such as piglets infected in utero; frequent lack of quality control and registration of vaccines and vaccinations; feeding of swine with contaminated food waste (swill); the common practice of smuggling animals and by-products across borders; the backyard family production system or extensive open field methods of swine rearing with minimal input in care and feeding; poor

  11. EVIDENCE OF PSEUDORABIES VIRUS SHEDDING IN FERAL SWINE ( SUS SCROFA) POPULATIONS OF FLORIDA, USA.

    Science.gov (United States)

    Hernández, Felipe A; Sayler, Katherine A; Bounds, Courtney; Milleson, Michael P; Carr, Amanda N; Wisely, Samantha M

    2018-01-01

    :  Feral swine ( Sus scrofa) are a pathogen reservoir for pseudorabies virus (PrV). The virus can be fatal to wildlife and contributes to economic losses in the swine industry worldwide. National surveillance efforts in the US use serology to detect PrV-specific antibodies in feral swine populations, but PrV exposure is not a direct indicator of pathogen transmission among conspecifics or to non-suid wildlife species. We measured antibody production and the presence of PrV DNA in four tissue types from feral swine populations of Florida, US. We sampled blood, nasal, oral, and genital swabs from 551 individuals at 39 sites during 2014-16. Of the animals tested for antibody production, 224 of 436 (51%) feral swine were antibody positive while 38 of 549 feral swine (7%) tested for viral shedding were quantitative polymerase chain reaction (qPCR)-positive for PrV. The detection of PrV DNA across all the collected sample types (blood, nasal, oral, and genital [vaginal] swabs) suggested viral shedding via direct (oronasal or venereal), and potentially indirect (through carcass consumption), routes of transmission among infected and susceptible animals. Fourteen of 212 seronegative feral swine were qPCR-positive, indicating 7% false negatives in the serologic assay. Our findings suggest that serology may underestimate the actual infection risk posed by feral swine to other species and that feral swine populations in Florida are capable of shedding the virus through multiple routes.

  12. Interaction of CSFV E2 protein with swine host factors as detected by yeast two-hybrid system

    Science.gov (United States)

    E2 is one of the envelope glycoproteins of pestiviruses, including classical swine fever virus (CSFV) and bovine viral diarrhea virus (BVDV). E2 is involved in several critical functions, including virus entry into target cells, induction of a protective immune response and virulence in swine. Howev...

  13. Hepatitis E virus infection in North Italy: high seroprevalence in swine herds and increased risk for swine workers.

    NARCIS (Netherlands)

    Mughini-Gras, L; Angeloni, G; Salata, C; Vonesch, N; D'Amico, W; Campagna, G; Natale, A; Zuliani, F; Ceglie, L; Monne, I; Vascellari, M; Capello, K; DI Martino, G; Inglese, N; Palù, G; Tomao, P; Bonfanti, L

    2017-01-01

    We determined the hepatitis E virus (HEV) seroprevalence and detection rate in commercial swine herds in Italy's utmost pig-rich area, and assessed HEV seropositivity risk in humans as a function of occupational exposure to pigs, diet, foreign travel, medical history and hunting activities. During

  14. Hepatitis E virus infection in North Italy : high seroprevalence in swine herds and increased risk for swine workers

    NARCIS (Netherlands)

    Mughini-Gras, L|info:eu-repo/dai/nl/413306046; Angeloni, Giorgia; Salata, C; Vonesch, N; D'Amico, W; Campagna, G; Natale, Alda; Zuliani, Federica; Ceglie, Letizia; Monne, Isabella; Vascellari, M; Capello, Katia; DI Martino, G; Inglese, N; Palù, G; Tomao, P; Bonfanti, L.

    2017-01-01

    We determined the hepatitis E virus (HEV) seroprevalence and detection rate in commercial swine herds in Italy's utmost pig-rich area, and assessed HEV seropositivity risk in humans as a function of occupational exposure to pigs, diet, foreign travel, medical history and hunting activities. During

  15. Genetic and pathogenic characteristics of H1 avian and swine influenza A viruses.

    Science.gov (United States)

    Kang, Hyun-Mi; Lee, Eun-Kyoung; Song, Byung-Min; Jeong, Jipseol; Kim, Hye-Ryoung; Choi, Eun-Jin; Shin, Yeun-Kyung; Lee, Hee-Soo; Lee, Youn-Jeong

    2014-10-01

    This study examined the potential for cross-species transmission of influenza viruses by comparing the genetic and pathogenic characteristics of H1 avian influenza viruses (AIVs) with different host origins in Korea. Antigenic and phylogenetic analyses of H1 AIVs circulating in Korea provided evidence of genetic similarity between viruses that infect domestic ducks and those that infect wild birds, although there was no relationship between avian and swine viruses. However, there were some relationships between swine and human viral genes. The replication and pathogenicity of the H1 viruses was assessed in chickens, domestic ducks and mice. Viral shedding in chickens was relatively high. Virus was recovered from both oropharyngeal and cloacal swabs up to 5-10 days post-inoculation. The titres of domestic duck viruses in chickens were much higher than those of wild-bird viruses. Both domestic duck and wild-bird viruses replicated poorly in domestic ducks. None of the swine viruses replicated in chickens or domestic ducks; however, six viruses showed relatively high titres in mice, regardless of host origin, and induced clinical signs such as ruffled fur, squatting and weight loss. Thus, although the phylogenetic and antigenic analyses showed no evidence of interspecies transmission between birds and swine, the results suggest that Korean H1 viruses have the potential to cause disease in mammals. Therefore, we should intensify continuous monitoring of avian H1 viruses in mammals and seek to prevent interspecies transmission. © 2014 The Authors.

  16. Effect of radiation on certain animal viruses in liquid swine manure

    International Nuclear Information System (INIS)

    Simon, J.; Mocsari, E.; Di Gleria, M.; Felkai, V.

    1983-01-01

    The virucidal effect of 60 Co γ-radiation was studied in cell culture medium and in liquid swine manure involving the most important porcine viruses that can be spread by liquid manure. The radiation doses, 20 and 30 kGy, were determined in preliminary experiments. At a radiation dose of 30 kGy, the activity of extracellular and cell-associated test viruses, except swine vesicular disease virus (SVDV), was completely destroyed both in cell culture medium and in liquid swine manure. The infectivity of SVDV decreased significantly (P 10 TCID 50 , both in cell culture medium and in liquid manure and this value corresponded to the international effectiveness demand for a disinfectant. The results showed that the safe disinfection virus in liquid swine manure by ionizing radiation requires a radiation dose of 30 kGy. (author)

  17. Estimation of the dynamics and rate of transmission of classical swine fever (hog cholera) in wild pigs.

    Science.gov (United States)

    Hone, J; Pech, R; Yip, P

    1992-04-01

    Infectious diseases establish in a population of wildlife hosts when the number of secondary infections is greater than or equal to one. To estimate whether establishment will occur requires extensive experience or a mathematical model of disease dynamics and estimates of the parameters of the disease model. The latter approach is explored here. Methods for estimating key model parameters, the transmission coefficient (beta) and the basic reproductive rate (RDRS), are described using classical swine fever (hog cholera) in wild pigs as an example. The tentative results indicate that an acute infection of classical swine fever will establish in a small population of wild pigs. Data required for estimation of disease transmission rates are reviewed and sources of bias and alternative methods discussed. A comprehensive evaluation of the biases and efficiencies of the methods is needed.

  18. Modeling the Effects of Duration and Size of the Control Zones on the Consequences of a Hypothetical African Swine Fever Epidemic in Denmark

    DEFF Research Database (Denmark)

    Halasa, Tariq; Bøtner, Anette; Mortensen, Sten

    2018-01-01

    control an epidemic of ASF. A previously published and well documented simulation model for ASF virus spread between herds was used to examine the epidemiologic and economic impacts of the duration and size of the control zones around affected herds. In the current study, scenarios were run, where......African swine fever (ASF) is a notifiable infectious disease. The disease is endemic in certain regions in Eastern Europe constituting a risk of ASF spread toward Western Europe. Therefore, as part of contingency planning, it is important to continuously explore strategies that can effectively...... or clinical and serological surveillance of herds within the zones. Sensitivity analysis was conducted on influential input parameters in the model. The model predicts that reducing the duration of the protection and surveillance zones has no impact on the epidemiological consequences of the epidemics, while...

  19. H1N1 influenza viruses varying widely in hemagglutinin stability transmit efficiently from swine to swine and to ferrets.

    Directory of Open Access Journals (Sweden)

    Marion Russier

    2017-03-01

    Full Text Available A pandemic-capable influenza virus requires a hemagglutinin (HA surface glycoprotein that is immunologically unseen by most people and is capable of supporting replication and transmission in humans. HA stabilization has been linked to 2009 pH1N1 pandemic potential in humans and H5N1 airborne transmissibility in the ferret model. Swine have served as an intermediate host for zoonotic influenza viruses, yet the evolutionary pressure exerted by this host on HA stability was unknown. For over 70 contemporary swine H1 and H3 isolates, we measured HA activation pH to range from pH 5.1 to 5.9 for H1 viruses and pH 5.3 to 5.8 for H3 viruses. Thus, contemporary swine isolates vary widely in HA stability, having values favored by both avian (pH >5.5 and human and ferret (pH ≤5.5 species. Using an early 2009 pandemic H1N1 (pH1N1 virus backbone, we generated three viruses differing by one HA residue that only altered HA stability: WT (pH 5.5, HA1-Y17H (pH 6.0, and HA2-R106K (pH 5.3. All three replicated in pigs and transmitted from pig-to-pig and pig-to-ferret. WT and R106 viruses maintained HA genotype and phenotype after transmission. Y17H (pH 6.0 acquired HA mutations that stabilized the HA protein to pH 5.8 after transmission to pigs and 5.5 after transmission to ferrets. Overall, we found swine support a broad range of HA activation pH for contact transmission and many recent swine H1N1 and H3N2 isolates have stabilized (human-like HA proteins. This constitutes a heightened pandemic risk and underscores the importance of ongoing surveillance and control efforts for swine viruses.

  20. Treatment with interferon-alpha delays disease in swine infected with a highly virulent CSFV strain

    Science.gov (United States)

    Classical swine fever (CSF) is an economically significant, highly contagious swine disease. The etiological agent, CSF virus (CSFV), is an enveloped virus with a positive-sense, single-stranded RNA genome, classified as a member of the genus Pestivirus within the family Flaviviridae (Becher et al.,...

  1. Characterization of Rift Valley fever virus MP-12 strain encoding NSs of Punta Toro virus or sandfly fever Sicilian virus.

    Science.gov (United States)

    Lihoradova, Olga A; Indran, Sabarish V; Kalveram, Birte; Lokugamage, Nandadeva; Head, Jennifer A; Gong, Bin; Tigabu, Bersabeh; Juelich, Terry L; Freiberg, Alexander N; Ikegami, Tetsuro

    2013-01-01

    Rift Valley fever virus (RVFV; genus Phlebovirus, family Bunyaviridae) is a mosquito-borne zoonotic pathogen which can cause hemorrhagic fever, neurological disorders or blindness in humans, and a high rate of abortion in ruminants. MP-12 strain, a live-attenuated candidate vaccine, is attenuated in the M- and L-segments, but the S-segment retains the virulent phenotype. MP-12 was manufactured as an Investigational New Drug vaccine by using MRC-5 cells and encodes a functional NSs gene, the major virulence factor of RVFV which 1) induces a shutoff of the host transcription, 2) inhibits interferon (IFN)-β promoter activation, and 3) promotes the degradation of dsRNA-dependent protein kinase (PKR). MP-12 lacks a marker for differentiation of infected from vaccinated animals (DIVA). Although MP-12 lacking NSs works for DIVA, it does not replicate efficiently in type-I IFN-competent MRC-5 cells, while the use of type-I IFN-incompetent cells may negatively affect its genetic stability. To generate modified MP-12 vaccine candidates encoding a DIVA marker, while still replicating efficiently in MRC-5 cells, we generated recombinant MP-12 encoding Punta Toro virus Adames strain NSs (rMP12-PTNSs) or Sandfly fever Sicilian virus NSs (rMP12-SFSNSs) in place of MP-12 NSs. We have demonstrated that those recombinant MP-12 viruses inhibit IFN-β mRNA synthesis, yet do not promote the degradation of PKR. The rMP12-PTNSs, but not rMP12-SFSNSs, replicated more efficiently than recombinant MP-12 lacking NSs in MRC-5 cells. Mice vaccinated with rMP12-PTNSs or rMP12-SFSNSs induced neutralizing antibodies at a level equivalent to those vaccinated with MP-12, and were efficiently protected from wild-type RVFV challenge. The rMP12-PTNSs and rMP12-SFSNSs did not induce antibodies cross-reactive to anti-RVFV NSs antibody and are therefore applicable to DIVA. Thus, rMP12-PTNSs is highly efficacious, replicates efficiently in MRC-5 cells, and encodes a DIVA marker, all of which are

  2. Crimean-Congo Hemorrhagic Fever Virus in Bulgaria and Turkey

    Czech Academy of Sciences Publication Activity Database

    Mertens, M.; Schuster, I.; Sas, M. A.; Vatansever, Z.; Hubálek, Zdeněk; Güven, E.; Deniz, A.; Georgiev, G.; Peshev, R.; Groschup, M. H.

    2016-01-01

    Roč. 16, č. 9 (2016), s. 619-623 ISSN 1530-3667 EU Projects: European Commission(XE) 261504 - EDENEXT Institutional support: RVO:68081766 Keywords : Crimean-Congo hemorrhagic fever virus: CCHFV * domestic animals * ELISA * epidemiology Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.045, year: 2016

  3. Comparison of sampling techniques for Rift Valley Fever virus ...

    African Journals Online (AJOL)

    We investigated mosquito sampling techniques with two types of traps and attractants at different time for trapping potential vectors for Rift Valley Fever virus. The study was conducted in six villages in Ngorongoro district in Tanzania from September to October 2012. A total of 1814 mosquitoes were collected, of which 738 ...

  4. Stochastic spatio-temporal modelling of African swine fever spread in the European Union during the high risk period.

    Science.gov (United States)

    Nigsch, Annette; Costard, Solenne; Jones, Bryony A; Pfeiffer, Dirk U; Wieland, Barbara

    2013-03-01

    African swine fever (ASF) is a notifiable viral pig disease with high mortality and serious socio-economic consequences. Since ASF emerged in Georgia in 2007 the disease has spread to several neighbouring countries and cases have been detected in areas bordering the European Union (EU). It is uncertain how fast the virus would be able to spread within the unrestricted European trading area if it were introduced into the EU. This project therefore aimed to develop a model for the spread of ASF within and between the 27 Member States (MS) of the EU during the high risk period (HRP) and to identify MS during that period would most likely contribute to ASF spread ("super-spreaders") or MS that would most likely receive cases from other MS ("super-receivers"). A stochastic spatio-temporal state-transition model using simulated individual farm records was developed to assess silent ASF virus spread during different predefined HRPs of 10-60 days duration. Infection was seeded into farms of different pig production types in each of the 27 MS. Direct pig-to-pig transmission and indirect transmission routes (pig transport lorries and professional contacts) were considered the main pathways during the early stages of an epidemic. The model was parameterised using data collated from EUROSTAT, TRACES, a questionnaire sent to MS, and the scientific literature. Model outputs showed that virus circulation was generally limited to 1-2 infected premises per outbreak (95% IQR: 1-4; maximum: 10) with large breeder farms as index case resulting in most infected premises. Seven MS caused between-MS spread due to intra-Community trade during the first 10 days after seeding infection. For a HRP of 60 days from virus introduction, movements of infected pigs will originate at least once from 16 MS, with 6 MS spreading ASF in more than 10% of iterations. Two thirds of all intra-Community spread was linked to six trade links only. Denmark, the Netherlands, Lithuania and Latvia were identified

  5. Assessment of zoonotic potential of four European swine influenza viruses in the ferret model

    DEFF Research Database (Denmark)

    Fobian, Kristina; P. Fabrizio, Thomas; Yoon, Sun-Woo

    herds and enhanced focus on risk assessment of these new viruses. In this study, four European swine influenza viruses were assessed for their zoonotic potential. Of the four viruses, two were enzootic viruses of subtype H1N2 (with avian-like H1) and H3N2 and two were new reassortants, one with avian......The reverse zoonotic events that introduced the 2009 pandemic influenza virus into swine herds have drastically increased the diversity of reassortants throughout Europe. The pandemic potential of these novel reassortments is unknown, hence necessitating enhanced surveillance of European swine...... to neuraminidase inhibitors. These findings suggest that the investigated viruses have the potential to infect humans and further underline the need for continued surveillance as well as pandemic and zoonotic assessment of new influenza reassortants....

  6. A novel alphavirus replicon-vectored vaccine delivered by adenovirus induces sterile immunity against classical swine fever.

    Science.gov (United States)

    Sun, Yuan; Li, Hong-Yu; Tian, Da-Yong; Han, Qiu-Ying; Zhang, Xin; Li, Na; Qiu, Hua-Ji

    2011-10-26

    Low efficacy of gene-based vaccines due to inefficient gene delivery and expression has been major bottleneck of their applications. Efforts have been made to improve the efficacy, such as gene gun and electroporation, but the strategies are difficult to put into practical use. In this study, we developed and evaluated an adenovirus-delivered, alphavirus replicon-vectored vaccine (chimeric vector-based vaccine) expressing the E2 gene of classical swine fever virus (CSFV) (rAdV-SFV-E2). Rabbits immunized with rAdV-SFV-E2 developed CSFV-specific antibodies as early as 9 days and as long as 189 days and completely protected from challenge with C-strain. Pigs immunized with rAdV-SFV-E2 (n=5) developed robust humoral and cell-mediated responses to CSFV and were completely protected from subsequent lethal CSFV infection clinically and virologically. The level of immunity and protection induced by rAdV-SFV-E2 was comparable to that provided by the currently used live attenuated vaccine, C-strain. In contrast, both the conventional alphavirus replicon-vectored vaccine pSFV1CS-E2 and conventional adenovirus-vectored vaccine rAdV-E2 provided incomplete protection. The chimeric vector-based vaccine represents the first gene-based vaccine that is able to confer sterile immunity and complete protection against CSFV. The new-concept vaccination strategy may also be valuable in vaccine development against other pathogens. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Knowledge, Attitudes and Practices Related to African Swine Fever Within Smallholder Pig Production in Northern Uganda.

    Science.gov (United States)

    Chenais, E; Boqvist, S; Sternberg-Lewerin, S; Emanuelson, U; Ouma, E; Dione, M; Aliro, T; Crafoord, F; Masembe, C; Ståhl, K

    2017-02-01

    Uganda is a low-income country with the largest pig population in East Africa. Pig keeping has a large potential, commercially and as a tool for poverty reduction, but African swine fever (ASF) is a major hurdle for development of the sector. The objective of this study was to evaluate knowledge, attitudes and practices related to ASF in the smallholder pig production value chain in northern Uganda. The study included three separate series of participatory rural appraisals (PRA), comprising purposively selected farmers and other actors in the pig production value chain. In the PRAs, various participatory epidemiology tools were used. A total of 49 PRAs and 574 participants, representing 64 different villages, were included. The results indicate that participants were well aware of the clinical signs of ASF, routes for disease spread and measures for disease control. However, awareness of the control measures did not guarantee their implementation. A majority of middlemen and butchers acknowledged having sold live pigs, carcasses or pork they believed infected with ASF. Outbreaks of ASF had a strong negative impact on participants' socio-economic status with loss of revenue and reversal into more severe poverty. In conclusion, lack of knowledge is not what is driving the continuous circulation of ASF virus in this setting. To control ASF and reduce its impact, initiatives that stimulate changes in management are needed. Because the behaviour of all actors in the value chain is largely influenced by the deep rural poverty in the region, this needs to be combined with efforts to reduce rural poverty. © 2015 Blackwell Verlag GmbH.

  8. Molecular detection of African swine fever virus in apparently ...

    African Journals Online (AJOL)

    Management of pigs was predominantly semi-intensive (87.4%) with most of the pens built with mud bricks (51.5%), 31% built with concrete and 18.4% with wooden materials. Most of the farmers have formal education while 14.6% do not have any form of education. However, 23.3% of farms had a history of tick infestation ...

  9. Molecular characterization of African swine fever virus in apparently ...

    African Journals Online (AJOL)

    SAM

    2014-06-18

    Jun 18, 2014 ... Bands of correct size were excised and purified by ... acid sequences were manually aligned with gaps being inserted to .... Amino acid sequence alignment of the tetrameric tandem repeats identified within the central variable ...

  10. Accelerating vaccine development for African swine fever virus ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2018-01-12

    Jan 12, 2018 ... Engineering a wild fast-growing Mycoplasma bacterium to generate a novel vaccine for contagious caprine ... Engineering vaccines against hemorrhagic septicemia in ruminants ... Solutions. Careers · Contact Us · Site map.

  11. Live poultry market workers are susceptible to both avian and swine influenza viruses, Guangdong Province, China.

    Science.gov (United States)

    Chen, Jidang; Ma, Jun; White, Sarah K; Cao, Zhenpeng; Zhen, Yun; He, Shuyi; Zhu, Wanjun; Ke, Changwen; Zhang, Yongbiao; Su, Shuo; Zhang, Guihong

    2015-12-31

    Guangdong Province is recognized for dense populations of humans, pigs, poultry and pets. In order to evaluate the threat of viral infection faced by those working with animals, a cross-sectional, sero-epidemiological study was conducted in Guangdong between December 2013 and January 2014. Individuals working with swine, at poultry farms, or live poultry markets (LPM), and veterinarians, and controls not exposed to animals were enrolled in this study and 11 (4 human, 3 swine, 3 avian, and 1 canine) influenza A viruses were used in hemagglutination inhibition (HI) assays (7 strains) and the cross-reactivity test (9 strains) in which 5 strains were used in both tests. Univariate analysis was performed to identify which variables were significantly associated with seropositivity. Odds ratios (OR) revealed that swine workers had a significantly higher risk of elevated antibodies against A/swine/Guangdong/L6/2009(H1N1), a classical swine virus, and A/swine/Guangdong/SS1/2012(H1N1), a Eurasian avian-like swine virus than non-exposed controls. Poultry farm workers were at a higher risk of infection with avian influenza H7N9 and H9N2. LPM workers were at a higher risk of infection with 3 subtypes of avian influenza, H5N1, H7N9, and H9N2. Interestingly, the OR also indicated that LPM workers were at risk of H1N1 swine influenza virus infection, perhaps due to the presence of pigs in the LPM. While partial confounding by cross-reactive antibodies against human viruses or vaccines cannot be ruled out, our data suggests that animal exposed people as are more likely to have antibodies against animal influenza viruses. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Replication of swine and human influenza viruses in juvenile and layer turkey hens.

    Science.gov (United States)

    Ali, Ahmed; Yassine, Hadi; Awe, Olusegun O; Ibrahim, Mahmoud; Saif, Yehia M; Lee, Chang-Won

    2013-04-12

    Since the first reported isolation of swine influenza viruses (SIVs) in turkeys in the 1980s, transmission of SIVs to turkeys was frequently documented. Recently, the 2009 pandemic H1N1 virus, that was thought to be of swine origin, was detected in turkeys with a severe drop in egg production. In this study, we assessed the infectivity of different mammalian influenza viruses including swine, pandemic H1N1 and seasonal human influenza viruses in both juvenile and layer turkeys. In addition, we investigated the potential influenza virus dissemination in the semen of experimentally infected turkey toms. Results showed that all mammalian origin influenza viruses tested can infect turkeys. SIVs were detected in respiratory and digestive tracts of both juvenile and layer turkeys. Variations in replication efficiencies among SIVs were observed especially in the reproductive tract of layer turkeys. Compared to SIVs, limited replication of seasonal human H1N1 and no detectable replication of recent human-like swine H1N2, pandemic H1N1 and seasonal human H3N2 viruses was noticed. All birds seroconverted to all tested viruses regardless of their replication level. In turkey toms, we were able to detect swine H3N2 virus in semen and reproductive tract of infected toms by real-time RT-PCR although virus isolation was not successful. These data suggest that turkey hens could be affected by diverse influenza strains especially SIVs. Moreover, the differences in the replication efficiency we demonstrated among SIVs and between SIV and human influenza viruses in layer turkeys suggest a possible use of turkeys as an animal model to study host tropism and pathogenesis of influenza viruses. Our results also indicate a potential risk of venereal transmission of influenza viruses in turkeys. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. Are Swine Workers in the United States at Increased Risk of Infection with Zoonotic Influenza Virus?

    Science.gov (United States)

    Myers, Kendall P.; Olsen, Christopher W.; Setterquist, Sharon F.; Capuano, Ana W.; Donham, Kelley J.; Thacker, Eileen L.; Merchant, James A.; Gray, Gregory C.

    2006-01-01

    Background Pandemic influenza strains originate in nonhuman species. Pigs have an important role in interspecies transmission of the virus. We examined multiple swine-exposed human populations in the nation's number 1 swine-producing state for evidence of previous swine influenza virus infection. Methods We performed controlled, cross-sectional seroprevalence studies among 111 farmers, 97 meat processing workers, 65 veterinarians, and 79 control subjects using serum samples collected during the period of 2002–2004. Serum samples were tested using a hemagglutination inhibition assay against the following 6 influenza A virus isolates collected recently from pigs and humans: A/Swine/WI/238/97 (H1N1), A/Swine/WI/R33F/01 (H1N2), A/Swine/Minnesota/593/99 (H3N2), A/New Caledonia/20/99 (H1N1), A/Panama/2007/99 (H3N2), and A/Nanchang/933/95 (H3N2). Results Using multivariable proportional odds modeling, all 3 exposed study groups demonstrated markedly elevated titers against the H1N1 and H1N2 swine influenza virus isolates, compared with control subjects. Farmers had the strongest indication of exposure to swine H1N1 virus infection (odds ratio [OR], 35.3; 95% confidence interval [CI], 7.7–161.8), followed by veterinarians (OR, 17.8; 95% CI, 3.8–82.7), and meat processing workers (OR, 6.5; 95% CI, 1.4–29.5). Similarly, farmers had the highest odds for exposure to swine H1N2 virus (OR, 13.8; 95% CI, 5.4–35.4), followed by veterinarians (OR, 9.5; 95% CI, 3.6–24.6) and meat processing workers (OR, 2.7; 95% CI, 1.1–6.7). Conclusions Occupational exposure to pigs greatly increases workers' risk of swine influenza virus infection. Swine workers should be included in pandemic surveillance and in antiviral and immunization strategies. PMID:16323086

  14. Guinea pig model for evaluating the potential public health risk of swine and avian influenza viruses.

    Directory of Open Access Journals (Sweden)

    Yipeng Sun

    Full Text Available BACKGROUND: The influenza viruses circulating in animals sporadically transmit to humans and pose pandemic threats. Animal models to evaluate the potential public health risk potential of these viruses are needed. METHODOLOGY/PRINCIPAL FINDINGS: We investigated the guinea pig as a mammalian model for the study of the replication and transmission characteristics of selected swine H1N1, H1N2, H3N2 and avian H9N2 influenza viruses, compared to those of pandemic (H1N1 2009 and seasonal human H1N1, H3N2 influenza viruses. The swine and avian influenza viruses investigated were restricted to the respiratory system of guinea pigs and shed at high titers in nasal tracts without prior adaptation, similar to human strains. None of the swine and avian influenza viruses showed transmissibility among guinea pigs; in contrast, pandemic (H1N1 2009 virus transmitted from infected guinea pigs to all animals and seasonal human influenza viruses could also horizontally transmit in guinea pigs. The analysis of the receptor distribution in the guinea pig respiratory tissues by lectin histochemistry indicated that both SAα2,3-Gal and SAα2,6-Gal receptors widely presented in the nasal tract and the trachea, while SAα2,3-Gal receptor was the main receptor in the lung. CONCLUSIONS/SIGNIFICANCE: We propose that the guinea pig could serve as a useful mammalian model to evaluate the potential public health threat of swine and avian influenza viruses.

  15. Guinea pig model for evaluating the potential public health risk of swine and avian influenza viruses.

    Science.gov (United States)

    Sun, Yipeng; Bi, Yuhai; Pu, Juan; Hu, Yanxin; Wang, Jingjing; Gao, Huijie; Liu, Linqing; Xu, Qi; Tan, Yuanyuan; Liu, Mengda; Guo, Xin; Yang, Hanchun; Liu, Jinhua

    2010-11-23

    The influenza viruses circulating in animals sporadically transmit to humans and pose pandemic threats. Animal models to evaluate the potential public health risk potential of these viruses are needed. We investigated the guinea pig as a mammalian model for the study of the replication and transmission characteristics of selected swine H1N1, H1N2, H3N2 and avian H9N2 influenza viruses, compared to those of pandemic (H1N1) 2009 and seasonal human H1N1, H3N2 influenza viruses. The swine and avian influenza viruses investigated were restricted to the respiratory system of guinea pigs and shed at high titers in nasal tracts without prior adaptation, similar to human strains. None of the swine and avian influenza viruses showed transmissibility among guinea pigs; in contrast, pandemic (H1N1) 2009 virus transmitted from infected guinea pigs to all animals and seasonal human influenza viruses could also horizontally transmit in guinea pigs. The analysis of the receptor distribution in the guinea pig respiratory tissues by lectin histochemistry indicated that both SAα2,3-Gal and SAα2,6-Gal receptors widely presented in the nasal tract and the trachea, while SAα2,3-Gal receptor was the main receptor in the lung. We propose that the guinea pig could serve as a useful mammalian model to evaluate the potential public health threat of swine and avian influenza viruses.

  16. Educating youth swine exhibitors on influenza A virus transmission at agricultural fairs.

    Science.gov (United States)

    Nolting, J M; Midla, J; Whittington, M S; Scheer, S D; Bowman, A S

    2018-02-01

    Influenza A virus (IAV) is a major zoonotic pathogen that threatens global public health. Novel strains of influenza A viruses pose a significant risk to public health due to their pandemic potential, and transmission of influenza A viruses from animals to humans is an important mechanism in the generation and introduction of IAVs that threaten human health. The purpose of this descriptive correlational study was to develop real-life training scenarios to better inform swine exhibitors of the risks they may encounter when influenza A viruses are present in swine. Educational activities were implemented in five Ohio counties where exhibition swine had historically been shedding influenza A viruses during the county fair. A total of 146 youth swine exhibitors participated in the educational programme, and an increase in the knowledge base of these youth was documented. It is expected that educating youth exhibitors about exposure to influenza A virus infections in the swine they are exhibiting will result in altered behaviours and animal husbandry practices that will improve both human and animal health. © 2017 Blackwell Verlag GmbH.

  17. Reassortant swine influenza viruses isolated in Japan contain genes from pandemic A(H1N1) 2009.

    Science.gov (United States)

    Kanehira, Katsushi; Takemae, Nobuhiro; Uchida, Yuko; Hikono, Hirokazu; Saito, Takehiko

    2014-06-01

    In 2013, three reassortant swine influenza viruses (SIVs)-two H1N2 and one H3N2-were isolated from symptomatic pigs in Japan; each contained genes from the pandemic A(H1N1) 2009 virus and endemic SIVs. Phylogenetic analysis revealed that the two H1N2 viruses, A/swine/Gunma/1/2013 and A/swine/Ibaraki/1/2013, were reassortants that contain genes from the following three distinct lineages: (i) H1 and nucleoprotein (NP) genes derived from a classical swine H1 HA lineage uniquely circulating among Japanese SIVs; (ii) neuraminidase (NA) genes from human-like H1N2 swine viruses; and (iii) other genes from pandemic A(H1N1) 2009 viruses. The H3N2 virus, A/swine/Miyazaki/2/2013, comprised genes from two sources: (i) hemagglutinin (HA) and NA genes derived from human and human-like H3N2 swine viruses and (ii) other genes from pandemic A(H1N1) 2009 viruses. Phylogenetic analysis also indicated that each of the reassortants may have arisen independently in Japanese pigs. A/swine/Miyazaki/2/2013 were found to have strong antigenic reactivities with antisera generated for some seasonal human-lineage viruses isolated during or before 2003, whereas A/swine/Miyazaki/2/2013 reactivities with antisera against viruses isolated after 2004 were clearly weaker. In addition, antisera against some strains of seasonal human-lineage H1 viruses did not react with either A/swine/Gunma/1/2013 or A/swine/Ibaraki/1/2013. These findings indicate that emergence and spread of these reassortant SIVs is a potential public health risk. © 2014 The Societies and Wiley Publishing Asia Pty Ltd.

  18. Swine Influenza Virus (H1N2) Characterization and Transmission in Ferrets, Chile.

    Science.gov (United States)

    Bravo-Vasquez, Nicolás; Karlsson, Erik A; Jimenez-Bluhm, Pedro; Meliopoulos, Victoria; Kaplan, Bryan; Marvin, Shauna; Cortez, Valerie; Freiden, Pamela; Beck, Melinda A; Hamilton-West, Christopher; Schultz-Cherry, Stacey

    2017-02-01

    Phylogenetic analysis of the influenza hemagglutinin gene (HA) has suggested that commercial pigs in Chile harbor unique human seasonal H1-like influenza viruses, but further information, including characterization of these viruses, was unavailable. We isolated influenza virus (H1N2) from a swine in a backyard production farm in Central Chile and demonstrated that the HA gene was identical to that in a previous report. Its HA and neuraminidase genes were most similar to human H1 and N2 viruses from the early 1990s and internal segments were similar to influenza A(H1N1)pdm09 virus. The virus replicated efficiently in vitro and in vivo and transmitted in ferrets by respiratory droplet. Antigenically, it was distinct from other swine viruses. Hemagglutination inhibition analysis suggested that antibody titers to the swine Chilean H1N2 virus were decreased in persons born after 1990. Further studies are needed to characterize the potential risk to humans, as well as the ecology of influenza in swine in South America.

  19. Toward the development of a one-dose classical swine fever subunit vaccine: antigen titration, immunity onset, and duration of immunity

    Science.gov (United States)

    Madera, Rachel F.; Wang, Lihua; Gong, Wenjie; Burakova, Yulia; Buist, Sterling; Nietfeld, Jerome; Henningson, Jamie; Cino-Ozuna, Ada G.; Tu, Changchun

    2018-01-01

    Highly contagious classical swine fever (CSF) remains a major trade and health problem in the pig industry, resulting in large economic losses worldwide. In CSF-endemic countries, attenuated CSF virus (CSFV) vaccines have been routinely used to control the disease. However, eradication of CSFV in a geographical area would require permanent reduction to zero presence of the virus. It is therefore of paramount importance to develop a safe, potent, and non-infectious CSF vaccine. We have previously reported on a cost-effective CSF E2 subunit vaccine, KNB-E2, which can protect against CSF symptoms in a single dose containing 75 µg of recombinant CSFV glycoprotein E2. In this study, we report on a series of animal studies undertaken to elucidate further the efficacy of KNB-E2. We found that pigs vaccinated with a single KNB-E2 dose containing 25 µg of recombinant CSFV glycoprotein E2 were protected from clinical symptoms of CSF. In addition, KNB-E2-mediated reduction of CSF symptoms was observed at two weeks post-vaccination and the vaccinated pigs continued to exhibit reduced CSF clinical signs when virus challenged at two months and four months post-vaccination. These results suggest that KNB-E2 effectively reduces CSF clinical signs, indicating the potential of this vaccine for safely minimizing CSF-related losses. PMID:29510474

  20. [Ebola and Marburg hemorrhagic fever viruses: update on filoviruses].

    Science.gov (United States)

    Leroy, E; Baize, S; Gonzalez, J P

    2011-04-01

    The Ebola and Marburg viruses are the sole members of the Filoviridae family of viruses. They are characterized by a long filamentous form that is unique in the viral world. Filoviruses are among the most virulent pathogens currently known to infect humans. They cause fulminating disease characterized by acute fever followed by generalized hemorrhagic syndrome that is associated with 90% mortality in the most severe forms. Epidemic outbreaks of Marburg and Ebola viruses have taken a heavy toll on human life in Central Africa and devastated large ape populations in Gabon and Republic of Congo. Since their discovery in 1967 (Marburg) and 1976 (Ebola), more than 2,300 cases and 1,670 deaths have been reported. These numbers pale in comparison with the burden caused by malnutrition or other infectious disease scourges in Africa such as malaria, cholera, AIDS, dengue or tuberculosis. However, due to their extremely high lethality, association with multifocal hemorrhaging and specificity to the African continent, these hemorrhagic fever viruses have given rise to great interest on the part not only of the international scientific community but also of the general public because of their perceived potential as biological weapons. Much research has been performed on these viruses and major progress has been made in knowledge of their ecology, epidemiology and physiopathology and in development of vaccine candidates and therapeutic schemes. The purpose of this review is to present the main developments in these particular fields in the last decade.

  1. 77 FR 68783 - Prospective Grant of Exclusive License: Veterinary Vaccines for Rift Valley Fever Virus

    Science.gov (United States)

    2012-11-16

    ... Grant of Exclusive License: Veterinary Vaccines for Rift Valley Fever Virus AGENCY: Centers for Disease..., filed 12/21/2007, entitled ``Development of Rift Valley Fever Virus Utilizing Reverse Genetics,'' US... (RVF) Viruses and Method of Use,'' PCT Application PCT/US2008/ 087023, filed 12/16/2008, entitled...

  2. Influenza A virus infection dynamics in swine farms in Belgium, France, Italy and Spain 2006-2008

    NARCIS (Netherlands)

    Kyriakis, C.S.; Rose, N.; Foni, E.; Maldonado, J.; Loeffen, W.L.A.; Madec, F.; Simon, G.; Reeth, K.

    2013-01-01

    Avian-like H1N1 and reassortant H3N2 and H1N2 influenza A viruses with a human-like haemagglutinin have been co-circulating in swine in Europe for more than a decade. We aimed to examine the infection dynamics of the three swine influenza virus (SIV) lineages at the farm level, and to identify

  3. Interim Report on SNP analysis and forensic microarray probe design for South American hemorrhagic fever viruses, tick-borne encephalitis virus, henipaviruses, Old World Arenaviruses, filoviruses, Crimean-Congo hemorrhagic fever viruses, Rift Valley fever

    Energy Technology Data Exchange (ETDEWEB)

    Jaing, C; Gardner, S

    2012-06-05

    The goal of this project is to develop forensic genotyping assays for select agent viruses, enhancing the current capabilities for the viral bioforensics and law enforcement community. We used a multipronged approach combining bioinformatics analysis, PCR-enriched samples, microarrays and TaqMan assays to develop high resolution and cost effective genotyping methods for strain level forensic discrimination of viruses. We have leveraged substantial experience and efficiency gained through year 1 on software development, SNP discovery, TaqMan signature design and phylogenetic signature mapping to scale up the development of forensics signatures in year 2. In this report, we have summarized the whole genome wide SNP analysis and microarray probe design for forensics characterization of South American hemorrhagic fever viruses, tick-borne encephalitis viruses and henipaviruses, Old World Arenaviruses, filoviruses, Crimean-Congo hemorrhagic fever virus, Rift Valley fever virus and Japanese encephalitis virus.

  4. New influenza A virus reassortments have been found in Danish swine in 2011

    DEFF Research Database (Denmark)

    Breum, Solvej Østergaard; Hjulsager, Charlotte Kristiane; Trebbien, Ramona

    2012-01-01

    viruses which have been circulating in Danish pigs since it was found for the first time in 1981. ii) H1N2 reassortant viruses which comprise HA from “avian like” H1N1 and NA from swine H3N2. The reassortant H1N2 virus was discovered in Danish pig for the first time in 2003 and is now well established......In 2011 a passive surveillance for influenza A virus was conducted in Danish swine. Tested samples were clinical samples from affected pigs submitted to the Danish National Veterinary Institute for swine influenza virus detection. In total 713 samples from 276 herds were analysed and about 24......% of the samples were positive for swine influenza virus. All influenza positive samples were tested for the H1N1pdm09 virus by a real time RT-PCR assay specific for the pandemic HA gene and 26% of the samples were positive. Subtyping of 90 samples by sequencing revealed the presence of; i) H1N1 “avian like...

  5. Real-time laboratory exercises to test contingency plans for classical swine fever: experiences from two national laboratories

    DEFF Research Database (Denmark)

    Koenen, K.; Uttenthal, Åse; Meindl-Böhmer, A.

    2007-01-01

    In order to adequately and efficiently handle outbreaks of contagious diseases such as classical swine fever (CSF), foot and mouth disease or highly pathogenic avian influenza, competent authorities and the laboratories involved have to be well prepared and must be in possession of functioning....... It is essential that these plans are established during ‘peace-time’ and are reviewed regularly. This paper provides suggestions on how to perform laboratory exercises to test preparedness and describes the experiences of two national reference laboratories for CSF. The major lesson learnt was the importance...

  6. Interspecies Interactions and Potential Influenza A Virus Risk in Small Swine Farms in Peru

    Science.gov (United States)

    2012-03-15

    and swine influenza viruses : our current understanding of the zoonotic risk. Vet Res 2007, 38(2):243–260. 4. Wertheim JO: When pigs fly: the avian ...first authors. Abstract Background The recent avian influenza epidemic in Asia and the H1N1 pandemic demonstrated that influenza A viruses pose a...prime “mixing vessels” due to the dual receptivity of their trachea to human and avian strains. Additionally, avian and human influenza viruses

  7. Surveillance programs in Denmark has revealed the circulation of novel reassortant influenza A viruses in swine

    DEFF Research Database (Denmark)

    Larsen, Lars Erik; Hjulsager, Charlotte Kristiane; Trebbien, Ramona

    2014-01-01

    avH1N1 and H3N2 which is different from the dominating European H1N2 subtype (1). The prevalence of the H1N1pdm09 virus in swine has increased since 2009 in some countries including Denmark. Here we present the results of the national passive surveillance program on influenza in swine performed from...... by the combination of the gene segments hemagglutinin (HA) and neuraminidase (NA). In most European countries, the avian-like (av)H1N1, the 2009 pandemic variant (H1N1pdm09), H1N2 and H3N2 subtypes have constituted the dominating SIV subtypes during recent years. In Denmark, the H1N2 subtype is a reassortant between......Swine influenza is a respiratory disease caused by multiple subtypes of influenza A virus. Swine influenza virus (SIV) is enzootic in swine populations in Europe, Asia, North and South America. The influenza A virus genome consist of eight distinct gene segments and SIV subtypes are defined...

  8. [Swine influenza virus: evolution mechanism and epidemic characterization--a review].

    Science.gov (United States)

    Qi, Xian; Lu, Chengping

    2009-09-01

    Pigs may play an important role in the evolution and ecology of influenza A virus. The tracheal epithelium of pigs contain both SA alpha 2,6 Gal and SA alpha 2,3 Gal receptors and can be infected with swine, human and avian viruses, therefore, pigs have been considered as an intermediate host for the adaptation of avian influenza viruses to humans or as mixing vessels for the generation of genetically reassortant viruses. Evolution patterns among swine influenza viruses including evolution of host adaptation, antigenic drift and genetic reassortment, and the latter is the main one. Unlike human influenza viruses, swine viruses have different epizootiological patterns in different areas of world, which is enzootic and geographic dependence. Currently, three predominant subtypes of influenza virus are prevalent in pig populations worldwide: H1N1, H3N2, and H1N2, and these include classical swine H1N1, avian-like H1N1, human-like H3N2, reassortant H3N2 and various genotype H1N2 viruses. In Europe, North America and China, influenza A viruses circulating in pigs are distinct in the genetic characteristics and genetic sources. Since 1979, three subtypes, avian-like H1N1, reassortant H1N2 and H3N2 viruses, have been co-circulating in European swine. Before 1998, classical H1N1 viruses were the exclusive cause of swine influenza in North America. However, after that, three triple-reassortant H1N2, H3N2 and H1N1 viruses with genes of human, swine and avian virus began to emerge in pigs. Genetically, the pandemic viruses emerging in human, so called influenza A (H1N1) viruses, contain genes from both Europe and North American SIV lineages. SIV is not the same as Europe and the United States in the prevalence and genetic background in China, mainly classical swine H1N1 and human-like H3N2 type virus. However, in recent years, SIV from Europe and North America have been introduced into Chinese pig herds, so more attention should be given on the evolutionary of SIV in China

  9. The first Swedish H1N2 swine influenza virus isolate represents an uncommon reassortant

    OpenAIRE

    Renström Lena HM; Isaksson Mats; Berg Mikael; Zohari Siamak; Widén Frederik; Metreveli Giorgi; Bálint Ádám; Wallgren Per; Belák Sándor; Segall Thomas; Kiss István

    2009-01-01

    Abstract The European swine influenza viruses (SIVs) show considerable diversity comprising different types of H1N1, H3N2, and H1N2 strains. The intensifying full genome sequencing efforts reveal further reassortants within these subtypes. Here we report the identification of an uncommon reassortant variant of H1N2 subtype influenza virus isolated from a pig in a multisite herd where H1N2 swine influenza was diagnosed for the first time in Sweden during the winter of 2008-2009. The majority o...

  10. Molecular analysis of yellow fever virus 17DD vaccine strain

    Directory of Open Access Journals (Sweden)

    Paulo R. Post

    1991-06-01

    Full Text Available The Oswaldo Cruz Foundation produces most of the yellow fever (YF vaccine prepared world wide. As part of a broader approach to determine the genetic variability in YF l7D seeds and vaccines and its relevance to viral attenuation the 17DD virus was purifed directly from chick embryo homogenates which is the source of virus used for vaccination of millions of people in Brazil and other countries for half a century. Neutralization and hemagglutination tests showed that the purified virus is similar to the original stock. Furthermore, radioimmune precipitation of 35S-methionine-labeled viral proteins using mouse hyperimmune ascitic fluid revealed identical patterns for the purified 17DD virus and the YF l7D-204 strain except for the 17DD E protein which migrated slower on SDS-PAGE. This difference is likely to be due to N-linked glycosylation. Finally, comparison by northern blot nybridization of virion RNAs of purified 17DD with two other strains of YF virus only fenome-sized molecules for all three viruses. These observations suggest that vaccine phenotype is primarily associated with the accumulation of mutations.

  11. Identification of swine influenza virus epitopes and analysis of multiple specificities expressed by cytotoxic T cell subsets

    DEFF Research Database (Denmark)

    Pedersen, Lasse Eggers; Breum, Solvej Østergaard; Riber, Ulla

    2014-01-01

    Background: Major histocompatibility complex (MHC) class I peptide binding and presentation are essential for antigen-specific activation of cytotoxic T lymphocytes (CTLs) and swine MHC class I molecules, also termed swine leukocyte antigens (SLA), thus play a crucial role in the process that leads...... to elimination of viruses such as swine influenza virus (SwIV). This study describes the identification of SLA-presented peptide epitopes that are targets for a swine CTL response, and further analyses multiple specificities expressed by SwIV activated CTL subsets. Findings: Four SwIV derived peptides were...

  12. Evidence of infection with avian, human, and swine influenza viruses in pigs in Cairo, Egypt.

    Science.gov (United States)

    Gomaa, Mokhtar R; Kandeil, Ahmed; El-Shesheny, Rabeh; Shehata, Mahmoud M; McKenzie, Pamela P; Webby, Richard J; Ali, Mohamed A; Kayali, Ghazi

    2018-02-01

    The majority of the Egyptian swine population was culled in the aftermath of the 2009 H1N1 pandemic, but small-scale growing remains. We sampled pigs from piggeries and an abattoir in Cairo. We found virological evidence of infection with avian H9N2 and H5N1 viruses as well as human pandemic H1N1 influenza virus. Serological evidence suggested previous exposure to avian H5N1 and H9N2, human pandemic H1N1, and swine avian-like and human-like viruses. This raises concern about potential reassortment of influenza viruses in pigs and highlights the need for better control and prevention of influenza virus infection in pigs.

  13. NSs protein of severe fever with thrombocytopenia syndrome virus suppresses interferon production through different mechanism than Rift Valley fever virus.

    Science.gov (United States)

    Zhang, S; Zheng, B; Wang, T; Li, A; Wan, J; Qu, J; Li, C H; Li, D; Liang, M

    Severe fever with thrombocytopenia syndrome virus (SFTSV) is a newly identified Phlebovirus that causes severe fever with thrombocytopenia syndrome. Our study demonstrated that SFTSV NSs functioned as IFN antagonist mainly by suppressing TBK1/IKKε-IRF3 signaling pathway. NSs interacted with and relocalized TANK-binding kinase 1 (TBK1) into NSs-induced cytoplasmic structures and this interaction could effectively inhibit downstream phosphorylation and dimerization of interferon regulatory factor 3 (IRF3), resulting in the suppression of antiviral signaling and IFN induction. Functional sites of SFTSV NSs binding with TBK1 were then studied and results showed that NSs had lost their IFN-inhibiting activity after deleting the 25 amino acids in N-terminal. Furthermore, the mechanism of Rift Valley fever virus (RVFV) NSs blocking IFN-β response were also investigated. Preliminary results showed that RVFV NSs proteins could neither interact nor co-localize with TBK1 in cytoplasm, but suppressed its expression levels, phosphorylation and dimerization of IRF3 in the subsequent steps, resulting in inhibition of the IFN-β production. Altogether, our data demonstrated the probable mechanism used by SFTSV to inhibit IFN responses which was different from RVFV and pointed toward a novel mechanism for RVFV suppressing IFN responses.

  14. What Does the Future Hold for Yellow Fever Virus? (I

    Directory of Open Access Journals (Sweden)

    Raphaëlle Klitting

    2018-06-01

    Full Text Available The recent resurgence of yellow fever virus (YFV activity in the tropical regions of Africa and South America has sparked renewed interest in this infamous arboviral disease. Yellow fever virus had been a human plague for centuries prior to the identification of its urban transmission vector, the Aedes (Stegomyia aegypti (Linnaeus mosquito species, and the development of an efficient live-attenuated vaccine, the YF-17D strain. The combination of vector-control measures and vaccination campaigns drastically reduced YFV incidence in humans on many occasions, but the virus never ceased to circulate in the forest, through its sylvatic invertebrate vector(s and vertebrate host(s. Outbreaks recently reported in Central Africa (2015–2016 and Brazil (since late 2016, reached considerable proportions in terms of spatial distribution and total numbers of cases, with multiple exports, including to China. In turn, questions about the likeliness of occurrence of large urban YFV outbreaks in the Americas or of a successful import of YFV to Asia are currently resurfacing. This two-part review describes the current state of knowledge and gaps regarding the molecular biology and transmission dynamics of YFV, along with an overview of the tools that can be used to manage the disease at individual, local and global levels.

  15. Controlling disease outbreaks in wildlife using limited culling: modelling classical swine fever incursions in wild pigs in Australia.

    Science.gov (United States)

    Cowled, Brendan D; Garner, M Graeme; Negus, Katherine; Ward, Michael P

    2012-01-16

    Disease modelling is one approach for providing new insights into wildlife disease epidemiology. This paper describes a spatio-temporal, stochastic, susceptible- exposed-infected-recovered process model that simulates the potential spread of classical swine fever through a documented, large and free living wild pig population following a simulated incursion. The study area (300 000 km2) was in northern Australia. Published data on wild pig ecology from Australia, and international Classical Swine Fever data was used to parameterise the model. Sensitivity analyses revealed that herd density (best estimate 1-3 pigs km-2), daily herd movement distances (best estimate approximately 1 km), probability of infection transmission between herds (best estimate 0.75) and disease related herd mortality (best estimate 42%) were highly influential on epidemic size but that extraordinary movements of pigs and the yearly home range size of a pig herd were not. CSF generally established (98% of simulations) following a single point introduction. CSF spread at approximately 9 km2 per day with low incidence rates (management in wildlife. An important finding was that it may only be necessary to cull or vaccinate relatively small proportions of a population to successfully contain and eradicate some wildlife disease epidemics.

  16. Propidium Monoazide Coupled with PCR Predicts Infectivity of Enteric Viruses in Swine Manure and Biofertilized Soil.

    Science.gov (United States)

    Fongaro, Gislaine; Hernández, Marta; García-González, María Cruz; Barardi, Célia Regina Monte; Rodríguez-Lázaro, David

    2016-03-01

    The use of propidium monoazide (PMA) coupled with real-time PCR (RT-qPCR or qPCR for RNA or DNA viruses, respectively) was assessed to discriminate infectious enteric viruses in swine raw manure, swine effluent from anaerobic biodigester (AB) and biofertilized soils. Those samples were spiked either with infectious and heat-inactivated human adenovirus-2 (HAdV-2) or mengovirus (vMC0), and PMA-qPCR/RT-qPCR allowed discriminating inactivated viruses from the infective particles, with significant reductions (>99.9%). Then, the procedure was further assayed to evaluate the presence and stability of two non-cultivable viruses (porcine adenovirus and rotavirus A) in natural samples (swine raw manure, swine effluent from AB and biofertilized soils); it demonstrated viral inactivation during the storage period at 23 °C. As a result, the combination of PMA coupled to real-time PCR can be a promising alternative for prediction of viral infectivity in comparison to more labour-intensive and costly techniques such as animal or tissue-culture infectivity methods, and for those viruses that do not have currently available cell culture techniques.

  17. Antigenic and genetic evolution of contemporary swine H1 influenza viruses in the United States.

    Science.gov (United States)

    Rajao, Daniela S; Anderson, Tavis K; Kitikoon, Pravina; Stratton, Jered; Lewis, Nicola S; Vincent, Amy L

    2018-05-01

    Several lineages of influenza A viruses (IAV) currently circulate in North American pigs. Genetic diversity is further increased by transmission of IAV between swine and humans and subsequent evolution. Here, we characterized the genetic and antigenic evolution of contemporary swine H1N1 and H1N2 viruses representing clusters H1-α (1A.1), H1-β (1A.2), H1pdm (1A.3.3.2), H1-γ (1A.3.3.3), H1-δ1 (1B.2.2), and H1-δ2 (1B.2.1) currently circulating in pigs in the United States. The δ1-viruses diversified into two new genetic clades, H1-δ1a (1B.2.2.1) and H1-δ1b (1B.2.2.2), which were also antigenically distinct from the earlier H1-δ1-viruses. Further characterization revealed that a few key amino acid changes were associated with antigenic divergence in these groups. The continued genetic and antigenic evolution of contemporary H1 viruses might lead to loss of vaccine cross-protection that could lead to significant economic impact to the swine industry, and represents a challenge to public health initiatives that attempt to minimize swine-to-human IAV transmission. Published by Elsevier Inc.

  18. Adaptive evolution during the establishment of European avian-like H1N1 influenza A virus in swine.

    Science.gov (United States)

    Joseph, Udayan; Vijaykrishna, Dhanasekaran; Smith, Gavin J D; Su, Yvonne C F

    2018-04-01

    An H1N1 subtype influenza A virus with all eight gene segments derived from wild birds (including mallards), ducks and chickens, caused severe disease outbreaks in swine populations in Europe beginning in 1979 and successfully adapted to form the European avian-like swine (EA-swine) influenza lineage. Genes of the EA-swine lineage that are clearly segregated from its closest avian relatives continue to circulate in swine populations globally and represent a unique opportunity to study the adaptive process of an avian-to-mammalian cross-species transmission. Here, we used a relaxed molecular clock model to test whether the EA-swine virus originated through the introduction of a single avian ancestor as an entire genome, followed by an analysis of host-specific selection pressures among different gene segments. Our data indicated independent introduction of gene segments via transmission of avian viruses into swine followed by reassortment events that occurred at least 1-4 years prior to the EA-swine outbreak. All EA-swine gene segments exhibit greater selection pressure than avian viruses, reflecting both adaptive pressures and relaxed selective constraints that are associated with host switching. Notably, we identified key amino acid mutations in the viral surface proteins (H1 and N1) that play a role in adaptation to new hosts. Following the establishment of EA-swine lineage, we observed an increased frequency of intrasubtype reassortment of segments compared to the earlier strains that has been associated with adaptive amino acid replacements, disease severity and vaccine escape. Taken together, our study provides key insights into the adaptive changes in viral genomes following the transmission of avian influenza viruses to swine and the early establishment of the EA-swine lineage.

  19. Presence of influenza viruses in backyard poultry and swine in El Yali wetland, Chile.

    Science.gov (United States)

    Bravo-Vasquez, N; Di Pillo, F; Lazo, A; Jiménez-Bluhm, P; Schultz-Cherry, S; Hamilton-West, C

    2016-11-01

    In South America little is known regarding influenza virus circulating in backyard poultry and swine populations. Backyard productive systems (BPS) that breed swine and poultry are widely distributed throughout Chile with high density in the central zone, and several BPS are located within the "El Yali" (EY) ecosystem, which is one of the most important wetlands in South America. Here, 130 different wild bird species have been described, of them, at least 22 species migrate yearly from North America for nesting. For this reason, EY is considered as a high-risk zone for avian influenza virus. This study aims to identify if backyard poultry and swine bred in the EY ecosystem have been exposed to influenza A virus and if so, to identify influenza virus subtypes. A biosecurity and handling survey was applied and samples were collected from BPS in two seasons (spring 2013 and fall 2014) for influenza seroprevalence, and in one season (fall 2014) for virus presence. Seroprevalence at BPS level was 42% (95% CI:22-49) during spring 2013 and 60% (95% CI 43-72) in fall 2014. rRT-PCR for the influenza A matrix gene indicated a viral prevalence of 27% (95% CI:14-39) at BPS level in fall 2014. Eight farms (73% of rRT-PCR positive farms) were also positive to the Elisa test at the same time. One BPS was simultaneously positive (rRT-PCR) in multiple species (poultry, swine and geese) and a H1N2 virus was identified from swine, exemplifying the risk that these BPS may pose for generation of novel influenza viruses. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Crimean Congo Hemorrhagic Fever Virus and Alkhurma (Alkhumra) Virus in Ticks in Djibouti.

    Science.gov (United States)

    Horton, Katherine C; Fahmy, Nermeen T; Watany, Noha; Zayed, Alia; Mohamed, Abro; Ahmed, Ammar Abdo; Rollin, Pierre E; Dueger, Erica L

    2016-10-01

    Crimean Congo hemorrhagic fever virus and Alkhumra virus, not previously reported in Djibouti, were detected among 141 (infection rate = 15.7 per 100, 95% CI: 13.4-18.1) tick pools from 81 (37%) cattle and 2 (infection rate = 0.2 per 100, 95% CI: 0.0-0.7) tick pools from 2 (1%) cattle, respectively, collected at an abattoir in 2010 and 2011.

  1. Molecular Insights into Crimean-Congo Hemorrhagic Fever Virus

    Directory of Open Access Journals (Sweden)

    Marko Zivcec

    2016-04-01

    Full Text Available Crimean-Congo hemorrhagic fever virus (CCHFV is a tick-borne pathogen that causes high morbidity and mortality. Efficacy of vaccines and antivirals to treat human CCHFV infections remains limited and controversial. Research into pathology and underlying molecular mechanisms of CCHFV and other nairoviruses is limited. Significant progress has been made in our understanding of CCHFV replication and pathogenesis in the past decade. Here we review the most recent molecular advances in CCHFV-related research, and provide perspectives on future research.

  2. Restriction of Rift Valley Fever Virus Virulence in Mosquito Cells

    Directory of Open Access Journals (Sweden)

    Sonja R. Gerrard

    2010-02-01

    Full Text Available Arboviruses are maintained in a natural cycle that requires blood-sucking arthropod and vertebrate hosts. Arboviruses are believed to persistently infect their arthropod host without overt pathology and cause acute infection with viremia in their vertebrate host. We have focused on elucidating how a specific arbovirus, Rift Valley fever (RVF virus, causes cytopathic effect in cells derived from vertebrates and non-cytopathic infection in cells derived from arthropods. We demonstrate that the vertebrate virulence factor, NSs, is functional in arthropod cells but is expressed at significantly lower levels in infected arthropod versus infected vertebrate cells.

  3. Simplifying sampling for African swine fever surveillance: Assessment of antibody and pathogen detection from blood swabs.

    Science.gov (United States)

    Carlson, J; Zani, L; Schwaiger, T; Nurmoja, I; Viltrop, A; Vilem, A; Beer, M; Blome, S

    2018-02-01

    African swine fever (ASF) is a notifiable disease with serious socio-economic consequences that has been present in wild boar in the Baltic States and Poland since 2014. An introduction of ASF is usually accompanied by increased mortality, making fallen wild boar and hunted animals with signs of disease the main target for early warning and passive surveillance. It is difficult, however, to encourage hunters and foresters to report and take samples from these cases. A pragmatic and easy sampling approach with quick-drying swabs could facilitate this. In this study, we further evaluated the use of dry blood swabs for the detection of ASFV antibody and genome with samples from animal trials and diagnostic submissions (blood, bone and organs) from Estonia. Compared to serum samples, dried blood swabs yielded 93.1% (95% confidence interval: [83.3, 98.1]) sensitivity and 100% [95.9, 100.0] specificity in a commercial ASFV antibody ELISA. Similarly, the swabs gave a sensitivity of 98.9% [93.4, 100.0] and a specificity of 98.1% [90.1, 100.0] for genome detection by a standard ASFV p72 qPCR when compared to EDTA blood. The same swabs were tested in a VP72-antibody lateral flow device, with a sensitivity of 94.7% [85.4, 98.9] and specificity of 96.1% [89.0, 99.2] compared to the serum ELISA. When GenoTube samples tested in ELISA and LFD were compared, the sensitivity was 96.3% [87.3, 99.5] and the specificity was 93.8% [86.0, 97.9]. This study demonstrates reliable detection of ASFV antibody and genome from swabs. A field test of the swabs with decomposed wild boar carcasses in an endemic area in Estonia also gave promising results. Thus, this technique is a practical approach for surveillance of ASF in both free and endemic areas. © 2017 Blackwell Verlag GmbH.

  4. Contribution of market value chain to the control of African swine fever in Zambia.

    Science.gov (United States)

    Siamupa, C; Saasa, N; Phiri, A M

    2018-01-01

    African swine fever (ASF) is a worldwide disease of pigs endemic in most sub-Saharan African countries. Zambia has been experiencing outbreaks of ASF for many years because the disease is endemic in the eastern part of the country, with incursion into the central part of Lusaka Province. The latest outbreaks of ASF in Lusaka occurred in 2013 with substantial pig mortalities, loss in trade, and cost of control measures and compensation of affected farmers. The aims of the study were to identify market value chain-related factors that were associated with ASF outbreaks and assess why these outbreaks are becoming frequent despite control measures being put in place. Using a mixed-method design, participants involved in the value chain were purposively sampled. Some pig farmers were included using a respondent-driven technique. Farmers came from Lusaka, Chilanga, Kafue, and Chongwe districts. Other participants included district veterinary officers, veterinary assistants, police officers, and veterinary staff manning veterinary checkpoints, abattoir and processing plant managers, meat inspectors, market chairpersons, and traders. Semi-structured questionnaires, in-depth interviews, and direct observations were used to collect data to come up with narrations, tables, and flow charts. In assessing the contribution of the value chain in ASF, aspects of ASF screening, market availability and procedures, knowledge on ASF transmission, occurrence of ASF outbreak, and regulation of pig movement were investigated. Despite government ASF control measures being applied, the following were noted: (1) low awareness levels of ASF transmission among pig farmers and traders; (2) only 50% of farmers had their animals screened for ASF before sale; (3) all the markets did not have the pork inspected; (4) laxity in enforcing livestock movement control because of inadequate police and veterinary staff manning checkpoints; (5) lack of enforcement of meat inspection and food safety

  5. Quantitative assessment of social and economic impact of African swine fever outbreaks in northern Uganda.

    Science.gov (United States)

    Chenais, Erika; Boqvist, Sofia; Emanuelson, Ulf; von Brömssen, Claudia; Ouma, Emily; Aliro, Tonny; Masembe, Charles; Ståhl, Karl; Sternberg-Lewerin, Susanna

    2017-09-01

    African swine fever (ASF) is one of the most important pig diseases, causing high case fatality rate and trade restrictions upon reported outbreaks. In Uganda, a low-income country with the largest pig population in East Africa, ASF is endemic. Animal disease impact is multidimensional and include social and economic impact along the value chain. In low-income settings, this impact keep people poor and push those that have managed to escape poverty back again. If the diseases can be controlled, their negative consequences can be mitigated. However, to successfully argue for investment in disease control, its cost-benefits need to be demonstrated. One part in the cost-benefit equations is disease impact quantification. The objective of this study was therefore to investigate the socio-economic impact of ASF outbreaks at household level in northern Uganda. In a longitudinal study, structured interviews with two hundred, randomly selected, pig-keeping households were undertaken three times with a six month interval. Questions related to family and pig herd demographics, pig trade and pig business. Associations between ASF outbreaks and economic and social impact variables were evaluated using linear regression models. The study showed that pigs were kept in extreme low-input-low-output farming systems involving only small monetary investments. Yearly incidence of ASF on household level was 19%. Increasing herd size was positively associated with higher economic output. The interaction between ASF outbreaks and the herd size showed that ASF outbreaks were negatively associated with economic output at the second interview occasion and with one out of two economic impact variables at the third interview occasion. No significant associations between the social impact variables included in the study and ASF outbreaks could be established. Trade and consumption of sick and dead pigs were coping strategies used to minimize losses of capital and animal protein. The results

  6. Novel reassortant of swine influenza H1N2 virus in Germany.

    Science.gov (United States)

    Zell, Roland; Motzke, Susann; Krumbholz, Andi; Wutzler, Peter; Herwig, Volker; Dürrwald, Ralf

    2008-01-01

    European porcine H1N2 influenza viruses arose after multiple reassortment steps involving a porcine influenza virus with avian-influenza-like internal segments and human H1N1 and H3N2 viruses in 1994. In Germany, H1N2 swine influenza viruses first appeared in 2000. Two German H1N2 swine influenza virus strains isolated from pigs with clinical symptoms of influenza are described. They were characterized by the neutralization test, haemagglutination inhibition (HI) test and complete sequencing of the viral genomes. The data demonstrate that these viruses represent a novel H1N2 reassortant. The viruses showed limited neutralization by sera raised against heterologous A/sw/Bakum/1,832/00-like H1N2 viruses. Sera pools from recovered pigs showed a considerably lower HI reaction, indicative of diagnostic difficulties in using the HI test to detect these viruses with A/sw/Bakum/1,832/00-like H1N2 antigens. Genome sequencing revealed the novel combination of the human-like HAH1 gene of European porcine H1N2 influenza viruses and the NAN2 gene of European porcine H3N2 viruses.

  7. Comparison of two real-time RT-PCR assays for differentiation of C-strain vaccinated from classical swine fever infected pigs and wild boars

    DEFF Research Database (Denmark)

    Widén, F.; Everett, H.; Blome, S.

    2014-01-01

    Classical swine fever is one of the most important infectious diseases for the pig industry worldwide due to its economic impact. Vaccination is an effective means to control disease, however within the EU its regular use is banned owing to the inability to differentiate infected and vaccinated a...

  8. Airborne detection and quantification of swine influenza a virus in air samples collected inside, outside and downwind from swine barns.

    Directory of Open Access Journals (Sweden)

    Cesar A Corzo

    Full Text Available Airborne transmission of influenza A virus (IAV in swine is speculated to be an important route of virus dissemination, but data are scarce. This study attempted to detect and quantify airborne IAV by virus isolation and RRT-PCR in air samples collected under field conditions. This was accomplished by collecting air samples from four acutely infected pig farms and locating air samplers inside the barns, at the external exhaust fans and downwind from the farms at distances up to 2.1 km. IAV was detected in air samples collected in 3 out of 4 farms included in the study. Isolation of IAV was possible from air samples collected inside the barn at two of the farms and in one farm from the exhausted air. Between 13% and 100% of samples collected inside the barns tested RRT-PCR positive with an average viral load of 3.20E+05 IAV RNA copies/m³ of air. Percentage of exhaust positive air samples also ranged between 13% and 100% with an average viral load of 1.79E+04 RNA copies/m³ of air. Influenza virus RNA was detected in air samples collected between 1.5 and 2.1 Km away from the farms with viral levels significantly lower at 4.65E+03 RNA copies/m³. H1N1, H1N2 and H3N2 subtypes were detected in the air samples and the hemagglutinin gene sequences identified in the swine samples matched those in aerosols providing evidence that the viruses detected in the aerosols originated from the pigs in the farms under study. Overall our results indicate that pigs can be a source of IAV infectious aerosols and that these aerosols can be exhausted from pig barns and be transported downwind. The results from this study provide evidence of the risk of aerosol transmission in pigs under field conditions.

  9. The phylogeny of yellow fever virus 17D vaccines.

    Science.gov (United States)

    Stock, Nina K; Boschetti, Nicola; Herzog, Christian; Appelhans, Marc S; Niedrig, Matthias

    2012-02-01

    In recent years the safety of the yellow fever live vaccine 17D came under scrutiny. The focus was on serious adverse events after vaccinations that resemble a wild type infection with yellow fever and whose reasons are still not known. Also the exact mechanism of attenuation of the vaccine remains unknown to this day. In this context, the standards of safety and surveillance in vaccine production and administration have been discussed. Therein embodied was the demand for improved documentation of the derivation of the seed virus used for yellow fever vaccine production. So far, there was just a historical genealogy available that is based on source area and passage level. However, there is a need for a documentation based on molecular information to get better insights into the mechanisms of pathology. In this work we sequenced the whole genome of different passages of the YFV-17D strain used by Crucell Switzerland AG for vaccine production. Using all other publically available 17D full genome sequences we compared the sequence variance of all vaccine strains and oppose a phylogenetic tree based on full genome sequences to the historical genealogy. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Neutralizing antibodies against flaviviruses, Babanki virus, and Rift Valley fever virus in Ugandan bats.

    Science.gov (United States)

    Kading, Rebekah C; Kityo, Robert M; Mossel, Eric C; Borland, Erin M; Nakayiki, Teddie; Nalikka, Betty; Nyakarahuka, Luke; Ledermann, Jeremy P; Panella, Nicholas A; Gilbert, Amy T; Crabtree, Mary B; Peterhans, Julian Kerbis; Towner, Jonathan S; Amman, Brian R; Sealy, Tara K; Nichol, Stuart T; Powers, Ann M; Lutwama, Julius J; Miller, Barry R

    2018-01-01

    Introduction: A number of arboviruses have previously been isolated from naturally-infected East African bats, however the role of bats in arbovirus maintenance is poorly understood. The aim of this study was to investigate the exposure history of Ugandan bats to a panel of arboviruses. Materials and methods: Insectivorous and fruit bats were captured from multiple locations throughout Uganda during 2009 and 2011-2013. All serum samples were tested for neutralizing antibodies against West Nile virus (WNV), yellow fever virus (YFV), dengue 2 virus (DENV-2), Zika virus (ZIKV), Babanki virus (BBKV), and Rift Valley fever virus (RVFV) by plaque reduction neutralization test (PRNT). Sera from up to 626 bats were screened for antibodies against each virus. Results and Discussion:  Key findings include the presence of neutralizing antibodies against RVFV in 5/52 (9.6%) of little epauletted fruit bats ( Epomophorus labiatus ) captured from Kawuku and 3/54 (5.6%) Egyptian rousette bats from Kasokero cave. Antibodies reactive to flaviviruses were widespread across bat taxa and sampling locations. Conclusion: The data presented demonstrate the widespread exposure of bats in Uganda to arboviruses, and highlight particular virus-bat associations that warrant further investigation.

  11. Vectors of Crimean Congo Hemorrhagic Fever Virus in Iran

    Directory of Open Access Journals (Sweden)

    Zakkyeh Telmadarraiy

    2015-10-01

    Full Text Available Background: Ticks are important vectors and reservoirs of Crimean Congo Hemorrhagic Fever (CCHF virus. Human beings may be infected whenever the normal life cycle of the infected ticks on non- human vertebrate hosts is interrupted by the undesirable presence of humans in the cycle. A total of 26 species of Argasid and Ixodid ticks have been recorded in Iran; including nine Hyalomma, two Rhipicephalus, two Dermacentor, five Haemaphysalis, two Boophilus, one Ixodes and two Argas as well as three Ornithodoros species as blood sucking ectoparasites of livestock and poultries. The present paper reviews tick vectors of CCHF virus in Iran, focusing on the role of ticks in different provinces of Iran using reverse transcription polymerase chain reaction (RT-PCR assay.Methods: During ten years study, 1054 tick specimens; including two species of Argasidae and 17 species of Ixodidae were examined for their infection to CCHF virus genome. The output of all studies as well as related publications were discussed in the current paper.Results: The results show that Rhipicephalus sanguineus, Hyalomma marginatum, H. anatolicum, H. asiaticum and H. dromedarii were known as the most frequent species which were positive for CCHF virus.Conclusion: The status of ticks which were positive for CCHF virus revealed that unlike the most common idea that Hyalomma species are the most important vectors of CCHF virus, other ticks including Rhipicephalus,Haemaphysalis and Dermacentor can be reservoir of this virus; thus, considering geographical distribution, type of host and environmental conditions, different tick control measurements should be carried out in areas with high incidence of CCHF disease.

  12. Vectors of Crimean Congo Hemorrhagic Fever Virus in Iran

    Science.gov (United States)

    Telmadarraiy, Zakkyeh; Chinikar, Sadegh; Vatandoost, Hassan; Faghihi, Faezeh; Hosseini-Chegeni, Asadollah

    2015-01-01

    Background: Ticks are important vectors and reservoirs of Crimean Congo Hemorrhagic Fever (CCHF) virus. Human beings may be infected whenever the normal life cycle of the infected ticks on non-human vertebrate hosts is interrupted by the undesirable presence of humans in the cycle. A total of 26 species of Argasid and Ixodid ticks have been recorded in Iran; including nine Hyalomma, two Rhipicephalus, two Dermacentor, five Haemaphysalis, two Boophilus, one Ixodes and two Argas as well as three Ornithodoros species as blood sucking ectoparasites of livestock and poultries. The present paper reviews tick vectors of CCHF virus in Iran, focusing on the role of ticks in different provinces of Iran using reverse transcription polymerase chain reaction (RT-PCR) assay. Methods: During ten years study, 1054 tick specimens; including two species of Argasidae and 17 species of Ixodidae were examined for their infection to CCHF virus genome. The output of all studies as well as related publications were discussed in the current paper. Results: The results show that Rhipicephalus sanguineus, Hyalomma marginatum, H. anatolicum, H. asiaticum and H. dromedarii were known as the most frequent species which were positive for CCHF virus. Conclusion: The status of ticks which were positive for CCHF virus revealed that unlike the most common idea that Hyalomma species are the most important vectors of CCHF virus, other ticks including Rhipicephalus, Haemaphysalis and Dermacentor can be reservoir of this virus; thus, considering geographical distribution, type of host and environmental conditions, different tick control measurements should be carried out in areas with high incidence of CCHF disease. PMID:26623426

  13. Molecular Epidemiology and Evolution of Influenza Viruses Circulating within European Swine between 2009 and 2013

    DEFF Research Database (Denmark)

    J. Watson, Simon; Langat, Pinky; M. Reid, Scott

    2015-01-01

    )pdm09 becoming established at a mean frequency of 8% across European countries. Notably, swine in the United Kingdom have largely had a replacement of the endemic Eurasian avian virus-like (“avian-like”) genotypes with A(H1N1)pdm09-derived genotypes. The high number of reassortant genotypes observed...

  14. Signifiance of Arginine 20 in the 2A protease for swine vesicular disease virus pathogenicity

    DEFF Research Database (Denmark)

    Inoue, Toru; Zhang, Zhidong; Wang, Leyuan

    2007-01-01

    Pathogenic and attenuated strains of swine vesicular disease virus (SVDV), an enterovirus, have been characterized previously and, by using chimeric infectious cDNA clones, the key determinants of pathogenicity in pigs have been mapped to the coding region for 1D–2A. Within this region, residue 20...

  15. New reassortant and enzootic European swine influenza 1 viruses transmits efficiently through direct contact in the ferret model

    DEFF Research Database (Denmark)

    Fobian, Kristina; P. Fabrizio, Thomas; Yoon, Sun-Woo

    2015-01-01

    The reverse zoonotic events that introduced the 2009 pandemic influenza virus into pigs have drastically increased the diversity of swine influenza viruses in Europe. The pandemic potential of these novel reassortments is still unclear, necessitating enhanced surveillance of European pigs...... with additional focus on risk assessment of these new viruses. In this study, four European swine influenza viruses were assessed for their zoonotic potential. Two of the four viruses were enzootic viruses of subtype H1N2 (with avian-like H1) and H3N2 and two were new reassortants, one with avian-like H1...... and human-like N2 and one with 2009 pandemic H1 and swine-like N2. All viruses replicated to high titers in nasal wash- and nasal turbinate samples from inoculated ferrets and transmitted efficiently by direct contact. Only the H3N2 virus transmitted to naïve ferrets via the airborne route. Growth kinetics...

  16. Innate Immune Response to Rift Valley Fever Virus in Goats

    Science.gov (United States)

    Nfon, Charles K.; Marszal, Peter; Zhang, Shunzhen; Weingartl, Hana M.

    2012-01-01

    Rift Valley fever (RVF), a re-emerging mosquito-borne disease of ruminants and man, was endemic in Africa but spread to Saudi Arabia and Yemen, meaning it could spread even further. Little is known about innate and cell-mediated immunity to RVF virus (RVFV) in ruminants, which is knowledge required for adequate vaccine trials. We therefore studied these aspects in experimentally infected goats. We also compared RVFV grown in an insect cell-line and that grown in a mammalian cell-line for differences in the course of infection. Goats developed viremia one day post infection (DPI), which lasted three to four days and some goats had transient fever coinciding with peak viremia. Up to 4% of peripheral blood mononuclear cells (PBMCs) were positive for RVFV. Monocytes and dendritic cells in PBMCs declined possibly from being directly infected with virus as suggested by in vitro exposure. Infected goats produced serum IFN-γ, IL-12 and other proinflammatory cytokines but not IFN-α. Despite the lack of IFN-α, innate immunity via the IL-12 to IFN-γ circuit possibly contributed to early protection against RVFV since neutralising antibodies were detected after viremia had cleared. The course of infection with insect cell-derived RVFV (IN-RVFV) appeared to be different from mammalian cell-derived RVFV (MAM-RVFV), with the former attaining peak viremia faster, inducing fever and profoundly affecting specific immune cell subpopulations. This indicated possible differences in infections of ruminants acquired from mosquito bites relative to those due to contact with infectious material from other animals. These differences need to be considered when testing RVF vaccines in laboratory settings. PMID:22545170

  17. 77 FR 68783 - Prospective Grant of Co-Exclusive License: Veterinary Vaccines for Rift Valley Fever Virus

    Science.gov (United States)

    2012-11-16

    ... Grant of Co-Exclusive License: Veterinary Vaccines for Rift Valley Fever Virus AGENCY: Centers for... Valley Fever Virus Utilizing Reverse Genetics,'' US Provisional Application 61/042,987, filed 4/7/2008, entitled ``Recombinant Rift Valley Fever (RVF) Viruses and Method of Use,'' PCT Application PCT/US2008...

  18. Pathogenic characteristics of a novel triple-reasserted H1N2 swine influenza virus.

    Science.gov (United States)

    Liu, Huili; Tao, Jie; Zhang, Pengchao; Yin, Xiuchen; Ha, Zhuo; Zhang, Chunling

    2016-07-01

    A novel triple reasserted H1N2 virus A/swine/Shanghai/1/2007 (SH07) was isolated from nasal swabs of weaned pig showing clinical symptoms of coughing and sneezing. To explore the virus characteristics, mice, chickens and pigs were selected for pathogenicity study. Pigs inoculated intranasally with 10(6) TCID50 SH07 showed clinical symptoms with coughing and sneezing, but no death. The virus nuclear acid was detected in many tissues using real-time PCR, which was mainly distributed in respiratory system particularly in the lungs. The virus was low-pathogenic to chickens with 10(6) TCID50 dose inoculation either via intramuscular or intranasal routes. However virus nuclear acid detection and virus isolation confirmed that the virus can also be found in nasal and rectum. When virus was inoculated into mice by intramuscular or intranasal routes we observed 100% and 80% lethality respectively. The third generation of samples passaged on MDCK cell were SIV positive in indirect immunofluorescence assay (IFA) using antiserum against H1N2 SIV. Furthermore, the lungs of mice showed obvious lesion with interstitial pneumonia. Data in our study suggest that SH07 is preferentially pathogenic to mammals rather than birds although it is a reasserting virus with the fragments from swine, human and avian origin. Copyright © 2016 International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

  19. Bioinformatics prediction of swine MHC class I epitopes from Porcine Reproductive and Respiratory Syndrome Virus

    DEFF Research Database (Denmark)

    Welner, Simon; Nielsen, Morten; Lund, Ole

    an effective CTL response against PRRSV, we have taken a bioinformatics approach to identify common PRRSV epitopes predicted to react broadly with predominant swine MHC (SLA) alleles. First, the genomic integrity and sequencing method was examined for 334 available complete PRRSV type 2 genomes leaving 104...... by the PopCover algorithm, providing a final list of 54 epitopes prioritized according to maximum coverage of PRRSV strains and SLA alleles. This bioinformatics approach provides a rational strategy for selecting peptides for a CTL-activating vaccine with broad coverage of both virus and swine diversity...

  20. Molecular epidemiology of novel swine origin influenza virus (S-OIV from Gwalior, India, 2009

    Directory of Open Access Journals (Sweden)

    Shukla Jyoti

    2011-06-01

    Full Text Available Abstract Background The H1N1pandemic virus is a newly emergent human influenza A virus that is closely related to a number of currently circulating pig viruses in the 'classic North American' and 'Eurasian' swine influenza virus lineages and thus referred as S-OIV. Since the first reports of the virus in humans in April 2009, H1N1 virus has spread to 168 countries and overseas territories. India also witnessed severe H1N1 pandemic virus epidemic with considerable morbidity and mortality in different parts starting from May 2009. Findings The suspected swine flu outbreak from Gwalior India during October- December 2009 was confirmed through S-OIV HA gene specific RT-LAMP and real time RT-PCR. Positive samples through CDC real time and Lamp assay were further processed for isolation of the virus. Full HA gene sequencing of the H1N1 isolates of Gwalior, India revealed 99% homology with California and other circulating novel swine flu viruses. Three major changes were observed at nucleotide level, while two major amino acid shifts were observed at the position C9W and I30M corresponding to the ORF with prototype strain. The HA gene sequence phylogeny revealed the circulation of two genetically distinct lineages belonging to Clade VII and Clade I of S-OIV. Conclusions Our findings also supported the earlier report about circulation of mixed genogroups of S-OIV in India. Therefore continuous monitoring of the genetic makeup of this newly emergent virus is essential to understand its evolution within the country.

  1. Genetic and antigenic characterization of influenza A virus circulating in Danish swine during the past decade

    DEFF Research Database (Denmark)

    Fobian, Kristina; Kirk, Isa Kristina; Breum, Solvej Østergaard

    Influenza A virus has been endemic in Danish swine for the last 30 years, with H1N1 and H1N2 being the dominating subtypes. The purpose of this study was to investigate the genetic and antigenic evolution of the influenza viruses found in Danish swine during the last 10 years. A total of 78 samples...... to the complex epidemiology of circulating swine influenza virus in Denmark and indicates that vaccine development targeted against Danish H1N1 and H1N2 need only to include few components for the induction of cross protection against the predominant strains. The study was supported by grants from “European......-synonymous substitutions for H1, N1 and N2 were found to be in agreement with previously observed values for Eurasian swine lineages. Calculation of possible glycosylation sites in the hemagglutinin gene revealed that the H1N2 and H1N1 subtypes had three well conserved glycosylation sites in common. The results of the HI...

  2. Serological and molecular epidemiology of Japanese encephalitis virus infections in swine herds in China, 2006-2012.

    Science.gov (United States)

    Chai, Chunxia; Wang, Qiao; Cao, Sanjie; Zhao, Qin; Wen, Yiping; Huang, Xiaobo; Wen, Xintian; Yan, Qiguai; Ma, Xiaoping; Wu, Rui

    2018-01-31

    Japanese encephalitis virus (JEV) is a mosquito-borne, zoonotic flavivirus causing viral encephalitis in humans and reproductive disorder in swine. JEV is prevalent throughout China in human; however, spatiotemporal analysis of JEV in Chinese swine herds has not been reported previously. Herein, we present serological and molecular epidemiological results and estimates of prevalence of JEV infections among swine herds in various regions of China. The results suggest that JEV infections are widespread and genotype I and III strains co-exist in the same regions. Therefore, there is an urgent need to monitor JEV infection status among swine herds in China.

  3. Serological and molecular epidemiology of Japanese encephalitis virus infections in swine herds in China, 2006–2012

    Science.gov (United States)

    Chai, Chunxia; Wang, Qiao; Cao, Sanjie; Zhao, Qin; Wen, Yiping; Huang, Xiaobo; Wen, Xintian; Yan, Qiguai; Ma, Xiaoping

    2018-01-01

    Japanese encephalitis virus (JEV) is a mosquito-borne, zoonotic flavivirus causing viral encephalitis in humans and reproductive disorder in swine. JEV is prevalent throughout China in human; however, spatiotemporal analysis of JEV in Chinese swine herds has not been reported previously. Herein, we present serological and molecular epidemiological results and estimates of prevalence of JEV infections among swine herds in various regions of China. The results suggest that JEV infections are widespread and genotype I and III strains co-exist in the same regions. Therefore, there is an urgent need to monitor JEV infection status among swine herds in China. PMID:28693301

  4. Design, development and experimental trialof a tailored cytotoxic T-cell vaccine againstPorcine Reproductive and RespiratorySyndrome Virus-2

    DEFF Research Database (Denmark)

    Welner, Simon

    Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most important threats against the global swine production industry. The virus infects alveolar macrophages that leads to respiratory distress, fever, pneumonia and gives way to secondary respiratory pathogens. Infection...

  5. Establishment of recombinase polymerase amplification assay for five hemorrhagic fever-related viruses

    Directory of Open Access Journals (Sweden)

    Xue-feng CAO

    2017-08-01

    Full Text Available Objective To establish a one-step recombinase polymerase amplification (RPA method for pathogen screening and rapid detection in the field targeting for five hemorrhagic fever related viruses (Zaire ebola virus, Sudan ebola virus, Marburg virus, Lassa virus and Yellow fever virus. Methods The specific nucleic acid (NA fragments of each virus were selected as target genes by genome sequence analysis, and the primers and probes for RPA assays were designed according to the sequence. A series of diluted template genes were used for RPA detection to determine the sensitivity. The hemorrhagic fever-related viral nucleic acids were used for RPA detection to determine the specificity. The amplification experiments were carried out at different temperature ranging from 37℃ to 42℃ to validate the reaction temperature range. Results The RPA reaction systems of the five hemorrhagic fever viruses could effectively amplify the target genes, the sensitivities were between 1.5×102 and 1.5×103 copies. No cross reactions existed with the other hemorrhagic fever-related viral genes. Meanwhile, RPA assay could effectively amplify the target genes at 37-42℃. Conclusion The isothermal RPA assays of five hemorrhagic fever viruses are established, which may amply target genes fast and react at a wide temperature range, and be potentially useful for in field pathogens detection. DOI: 10.11855/j.issn.0577-7402.2017.06.09

  6. Crimean-Congo Hemorrhagic Fever: Tick-Host-Virus Interactions

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    Anna Papa

    2017-05-01

    Full Text Available Crimean-Congo hemorrhagic fever virus (CCHFV is transmitted to humans by bite of infected ticks or by direct contact with blood or tissues of viremic patients or animals. It causes to humans a severe disease with fatality up to 30%. The current knowledge about the vector-host-CCHFV interactions is very limited due to the high-level containment required for CCHFV studies. Among ticks, Hyalomma spp. are considered the most competent virus vectors. CCHFV evades the tick immune response, and following its replication in the lining of the tick's midgut, it is disseminated by the hemolymph in the salivary glands and reproductive organs. The introduction of salivary gland secretions into the host cells is the major route via which CCHFV enters the host. Following an initial amplification at the site of inoculation, the virus is spread to the target organs. Apoptosis is induced via both intrinsic and extrinsic pathways. Genetic factors and immune status of the host may affect the release of cytokines which play a major role in disease progression and outcome. It is expected that the use of new technology of metabolomics, transcriptomics and proteomics will lead to improved understanding of CCHFV-host interactions and identify potential targets for blocking the CCHFV transmission.

  7. The origin of the PB1 segment of swine influenza A virus subtype H1N2 determines viral pathogenicity in mice.

    Science.gov (United States)

    Metreveli, Giorgi; Gao, Qinshan; Mena, Ignacio; Schmolke, Mirco; Berg, Mikael; Albrecht, Randy A; García-Sastre, Adolfo

    2014-08-08

    Swine appear to be a key species in the generation of novel human influenza pandemics. Previous pandemic viruses are postulated to have evolved in swine by reassortment of avian, human, and swine influenza viruses. The human pandemic influenza viruses that emerged in 1957 and 1968 as well as swine viruses circulating since 1998 encode PB1 segments derived from avian influenza viruses. Here we investigate the possible role in viral replication and virulence of the PB1 gene segments present in two swine H1N2 influenza A viruses, A/swine/Sweden/1021/2009(H1N2) (sw 1021) and A/swine/Sweden/9706/2010(H1N2) (sw 9706), where the sw 1021 virus has shown to be more pathogenic in mice. By using reverse genetics, we swapped the PB1 genes of these two viruses. Similar to the sw 9706 virus, chimeric sw 1021 virus carrying the sw 9706 PB1 gene was not virulent in mice. In contrast, replacement of the PB1 gene of the sw 9706 virus by that from sw 1021 virus resulted in increased pathogenicity. Our study demonstrated that differences in virulence of swine influenza virus subtype H1N2 are attributed at least in part to the PB1 segment. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Rift Valley fever virus infection in golden Syrian hamsters.

    Directory of Open Access Journals (Sweden)

    Dionna Scharton

    Full Text Available Rift Valley fever virus (RVFV is a formidable pathogen that causes severe disease and abortion in a variety of livestock species and a range of disease in humans that includes hemorrhagic fever, fulminant hepatitis, encephalitis and blindness. The natural transmission cycle involves mosquito vectors, but exposure can also occur through contact with infected fluids and tissues. The lack of approved antiviral therapies and vaccines for human use underlies the importance of small animal models for proof-of-concept efficacy studies. Several mouse and rat models of RVFV infection have been well characterized and provide useful systems for the study of certain aspects of pathogenesis, as well as antiviral drug and vaccine development. However, certain host-directed therapeutics may not act on mouse or rat pathways. Here, we describe the natural history of disease in golden Syrian hamsters challenged subcutaneously with the pathogenic ZH501 strain of RVFV. Peracute disease resulted in rapid lethality within 2 to 3 days of RVFV challenge. High titer viremia and substantial viral loads were observed in most tissues examined; however, histopathology and immunostaining for RVFV antigen were largely restricted to the liver. Acute hepatocellular necrosis associated with a strong presence of viral antigen in the hepatocytes indicates that fulminant hepatitis is the likely cause of mortality. Further studies to assess the susceptibility and disease progression following respiratory route exposure are warranted. The use of the hamsters to model RVFV infection is suitable for early stage antiviral drug and vaccine development studies.

  9. Animal Models of Tick-Borne Hemorrhagic Fever Viruses

    Directory of Open Access Journals (Sweden)

    Heinz Feldmann

    2013-05-01

    Full Text Available Tick-borne hemorrhagic fever viruses (TBHFV are detected throughout the African and Eurasian continents and are an emerging or re-emerging threat to many nations. Due to the largely sporadic incidences of these severe diseases, information on human cases and research activities in general have been limited. In the past decade, however, novel TBHFVs have emerged and areas of endemicity have expanded. Therefore, the development of countermeasures is of utmost importance in combating TBHFV as elimination of vectors and interrupting enzootic cycles is all but impossible and ecologically questionable. As in vivo models are the only way to test efficacy and safety of countermeasures, understanding of the available animal models and the development and refinement of animal models is critical in negating the detrimental impact of TBHFVs on public and animal health.

  10. Expression Dynamics of Innate Immunity in Influenza Virus-Infected Swine

    Directory of Open Access Journals (Sweden)

    Massimo Amadori

    2017-04-01

    Full Text Available The current circulating swine influenza virus (IV subtypes in Europe (H1N1, H1N2, and H3N2 are associated with clinical outbreaks of disease. However, we showed that pigs could be susceptible to other IV strains that are able to cross the species barrier. In this work, we extended our investigations into whether different IV strains able to cross the species barrier might give rise to different innate immune responses that could be associated with pathological lesions. For this purpose, we used the same samples collected in a previous study of ours, in which healthy pigs had been infected with a H3N2 Swine IV and four different H3N8 IV strains circulating in different animal species. Pigs had been clinically inspected and four subjects/group were sacrificed at 3, 6, and 21 days post infection. In the present study, all groups but mock exhibited antibody responses to IV nucleoprotein protein. Pulmonary lesions and high-titered viral replication were observed in pigs infected with the swine-adapted virus. Interestingly, pigs infected with avian and seal H3N8 strains also showed moderate lesions and viral replication, whereas equine and canine IVs did not cause overt pathological signs, and replication was barely detectable. Swine IV infection induced interferon (IFN-alpha and interleukin-6 responses in bronchoalveolar fluids (BALF at day 3 post infection, as opposed to the other non-swine-adapted virus strains. However, IFN-alpha responses to the swine-adapted virus were not associated with an increase of the local, constitutive expression of IFN-alpha genes. Remarkably, the Equine strain gave rise to a Serum Amyloid A response in BALF despite little if any replication. Each virus strain could be associated with expression of cytokine genes and/or proteins after infection. These responses were observed well beyond the period of virus replication, suggesting a prolonged homeostatic imbalance of the innate immune system.

  11. Transmission of yellow fever vaccine virus through breast-feeding - Brazil, 2009.

    Science.gov (United States)

    2010-02-12

    In April, 2009, the state health department of Rio Grande do Sul, Brazil, was notified by the Cachoeira do Sul municipal health department of a case of meningoencephalitis requiring hospitalization in an infant whose mother recently had received yellow fever vaccine during a postpartum visit. The Field Epidemiology Training Program of the Secretariat of Surveillance in Health of the Brazilian Ministry of Health assisted state and municipal health departments with an investigation. This report summarizes the results of that investigation, which determined that the infant acquired yellow fever vaccine virus through breast-feeding. The mother reported 2 days of headache, malaise, and low fever occurring 5 days after receipt of yellow fever vaccine. The infant, who was exclusively breast-fed, was hospitalized at age 23 days with seizures requiring continuous infusion of intravenous anticonvulsants. The infant received antimicrobial and antiviral treatment for meningoencephalitis. The presence of 17DD yellow fever virus was detected by reverse transcription--polymerase chain reaction (RT-PCR) in the infant's cerebrospinal fluid (CSF); yellow fever--specific immunoglobulin M (IgM) antibodies also were present in serum and CSF. The infant recovered completely, was discharged after 24 days of hospitalization, and has had normal neurodevelopment and growth through age 6 months. The findings in this report provide documentation that yellow fever vaccine virus can be transmitted via breast-feeding. Administration of yellow fever vaccine to breast-feeding women should be avoided except in situations where exposure to yellow fever viruses cannot be avoided or postponed.

  12. Functional requirements of the yellow fever virus capsid protein.

    Science.gov (United States)

    Patkar, Chinmay G; Jones, Christopher T; Chang, Yu-hsuan; Warrier, Ranjit; Kuhn, Richard J

    2007-06-01

    Although it is known that the flavivirus capsid protein is essential for genome packaging and formation of infectious particles, the minimal requirements of the dimeric capsid protein for virus assembly/disassembly have not been characterized. By use of a trans-packaging system that involved packaging a yellow fever virus (YFV) replicon into pseudo-infectious particles by supplying the YFV structural proteins using a Sindbis virus helper construct, the functional elements within the YFV capsid protein (YFC) were characterized. Various N- and C-terminal truncations, internal deletions, and point mutations of YFC were analyzed for their ability to package the YFV replicon. Consistent with previous reports on the tick-borne encephalitis virus capsid protein, YFC demonstrates remarkable functional flexibility. Nearly 40 residues of YFC could be removed from the N terminus while the ability to package replicon RNA was retained. Additionally, YFC containing a deletion of approximately 27 residues of the C terminus, including a complete deletion of C-terminal helix 4, was functional. Internal deletions encompassing the internal hydrophobic sequence in YFC were, in general, tolerated to a lesser extent. Site-directed mutagenesis of helix 4 residues predicted to be involved in intermonomeric interactions were also analyzed, and although single mutations did not affect packaging, a YFC with the double mutation of leucine 81 and valine 88 was nonfunctional. The effects of mutations in YFC on the viability of YFV infection were also analyzed, and these results were similar to those obtained using the replicon packaging system, thus underscoring the flexibility of YFC with respect to the requirements for its functioning.

  13. Assessment of African Swine Fever Diagnostic Techniques as a Response to the Epidemic Outbreaks in Eastern European Union Countries: How To Improve Surveillance and Control Programs.

    Science.gov (United States)

    Gallardo, C; Nieto, R; Soler, A; Pelayo, V; Fernández-Pinero, J; Markowska-Daniel, I; Pridotkas, G; Nurmoja, I; Granta, R; Simón, A; Pérez, C; Martín, E; Fernández-Pacheco, P; Arias, M

    2015-08-01

    This study represents a complete comparative analysis of the most widely used African swine fever (ASF) diagnostic techniques in the European Union (EU) using field and experimental samples from animals infected with genotype II ASF virus (ASFV) isolates circulating in Europe. To detect ASFV, three different PCRs were evaluated in parallel using 785 field and experimental samples. The results showed almost perfect agreement between the Universal ProbeLibrary (UPL-PCR) and the real-time (κ = 0.94 [95% confidence interval {CI}, 0.91 to 0.97]) and conventional (κ = 0.88 [95% CI, 0.83 to 0.92]) World Organisation for Animal Health (OIE)-prescribed PCRs. The UPL-PCR had greater diagnostic sensitivity for detecting survivors and allows earlier detection of the disease. Compared to the commercial antigen enzyme-linked immunosorbent assay (ELISA), good-to-moderate agreement (κ = 0.67 [95% CI, 0.58 to 0.76]) was obtained, with a sensitivity of 77.2% in the commercial test. For ASF antibody detection, five serological methods were tested, including three commercial ELISAs, the OIE-ELISA, and the confirmatory immunoperoxidase test (IPT). Greater sensitivity was obtained with the IPT than with the ELISAs, since the IPT was able to detect ASF antibodies at an earlier point in the serological response, when few antibodies are present. The analysis of the exudate tissues from dead wild boars showed that IPT might be a useful serological tool for determining whether or not animals had been exposed to virus infection, regardless of whether antibodies were present. In conclusion, the UPL-PCR in combination with the IPT was the most trustworthy method for detecting ASF during the epidemic outbreaks affecting EU countries in 2014. The use of the most appropriate diagnostic tools is critical when implementing effective control programs. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  14. Assessment of African Swine Fever Diagnostic Techniques as a Response to the Epidemic Outbreaks in Eastern European Union Countries: How To Improve Surveillance and Control Programs

    Science.gov (United States)

    Nieto, R.; Soler, A.; Pelayo, V.; Fernández-Pinero, J.; Markowska-Daniel, I.; Pridotkas, G.; Nurmoja, I.; Granta, R.; Simón, A.; Pérez, C.; Martín, E.; Fernández-Pacheco, P.; Arias, M.

    2015-01-01

    This study represents a complete comparative analysis of the most widely used African swine fever (ASF) diagnostic techniques in the European Union (EU) using field and experimental samples from animals infected with genotype II ASF virus (ASFV) isolates circulating in Europe. To detect ASFV, three different PCRs were evaluated in parallel using 785 field and experimental samples. The results showed almost perfect agreement between the Universal ProbeLibrary (UPL-PCR) and the real-time (κ = 0.94 [95% confidence interval {CI}, 0.91 to 0.97]) and conventional (κ = 0.88 [95% CI, 0.83 to 0.92]) World Organisation for Animal Health (OIE)-prescribed PCRs. The UPL-PCR had greater diagnostic sensitivity for detecting survivors and allows earlier detection of the disease. Compared to the commercial antigen enzyme-linked immunosorbent assay (ELISA), good-to-moderate agreement (κ = 0.67 [95% CI, 0.58 to 0.76]) was obtained, with a sensitivity of 77.2% in the commercial test. For ASF antibody detection, five serological methods were tested, including three commercial ELISAs, the OIE-ELISA, and the confirmatory immunoperoxidase test (IPT). Greater sensitivity was obtained with the IPT than with the ELISAs, since the IPT was able to detect ASF antibodies at an earlier point in the serological response, when few antibodies are present. The analysis of the exudate tissues from dead wild boars showed that IPT might be a useful serological tool for determining whether or not animals had been exposed to virus infection, regardless of whether antibodies were present. In conclusion, the UPL-PCR in combination with the IPT was the most trustworthy method for detecting ASF during the epidemic outbreaks affecting EU countries in 2014. The use of the most appropriate diagnostic tools is critical when implementing effective control programs. PMID:26041901

  15. A fusion-inhibiting peptide against Rift Valley fever virus inhibits multiple, diverse viruses.

    Directory of Open Access Journals (Sweden)

    Jeffrey W Koehler

    Full Text Available For enveloped viruses, fusion of the viral envelope with a cellular membrane is critical for a productive infection to occur. This fusion process is mediated by at least three classes of fusion proteins (Class I, II, and III based on the protein sequence and structure. For Rift Valley fever virus (RVFV, the glycoprotein Gc (Class II fusion protein mediates this fusion event following entry into the endocytic pathway, allowing the viral genome access to the cell cytoplasm. Here, we show that peptides analogous to the RVFV Gc stem region inhibited RVFV infectivity in cell culture by inhibiting the fusion process. Further, we show that infectivity can be inhibited for diverse, unrelated RNA viruses that have Class I (Ebola virus, Class II (Andes virus, or Class III (vesicular stomatitis virus fusion proteins using this single peptide. Our findings are consistent with an inhibition mechanism similar to that proposed for stem peptide fusion inhibitors of dengue virus in which the RVFV inhibitory peptide first binds to both the virion and cell membranes, allowing it to traffic with the virus into the endocytic pathway. Upon acidification and rearrangement of Gc, the peptide is then able to specifically bind to Gc and prevent fusion of the viral and endocytic membranes, thus inhibiting viral infection. These results could provide novel insights into conserved features among the three classes of viral fusion proteins and offer direction for the future development of broadly active fusion inhibitors.

  16. Induction of protective immunity in swine by recombinant bamboo mosaic virus expressing foot-and-mouth disease virus epitopes

    Directory of Open Access Journals (Sweden)

    Lin Na-Sheng

    2007-09-01

    Full Text Available Abstract Background Plant viruses can be employed as versatile vectors for the production of vaccines by expressing immunogenic epitopes on the surface of chimeric viral particles. Although several viruses, including tobacco mosaic virus, potato virus X and cowpea mosaic virus, have been developed as vectors, we aimed to develop a new viral vaccine delivery system, a bamboo mosaic virus (BaMV, that would carry larger transgene loads, and generate better immunity in the target animals with fewer adverse environmental effects. Methods We engineered the BaMV as a vaccine vector expressing the antigenic epitope(s of the capsid protein VP1 of foot-and-mouth disease virus (FMDV. The recombinant BaMV plasmid (pBVP1 was constructed by replacing DNA encoding the 35 N-terminal amino acid residues of the BaMV coat protein with that encoding 37 amino acid residues (T128-N164 of FMDV VP1. Results The pBVP1 was able to infect host plants and to generate a chimeric virion BVP1 expressing VP1 epitopes in its coat protein. Inoculation of swine with BVP1 virions resulted in the production of anti-FMDV neutralizing antibodies. Real-time PCR analysis of peripheral blood mononuclear cells from the BVP1-immunized swine revealed that they produced VP1-specific IFN-γ. Furthermore, all BVP1-immunized swine were protected against FMDV challenge. Conclusion Chimeric BaMV virions that express partial sequence of FMDV VP1 can effectively induce not only humoral and cell-mediated immune responses but also full protection against FMDV in target animals. This BaMV-based vector technology may be applied to other vaccines that require correct expression of antigens on chimeric viral particles.

  17. Ebola haemorrhagic fever virus: pathogenesis, immune responses, potential prevention.

    Science.gov (United States)

    Marcinkiewicz, Janusz; Bryniarski, Krzysztof; Nazimek, Katarzyna

    2014-01-01

    Ebola zoonotic RNA filovirus represents human most virulent and lethal pathogens, which induces acute hemorrhagic fever and death within few days in a range of 60-90% of symptomatic individuals. Last outbreak in 2014 in West Africa caused panic that Ebola epidemic can be spread to other continents. Number of deaths in late December reached almost 8,000 individuals out of more than 20,000 symptomatic patients. It seems that only a coordinated international response could counteract the further spread of Ebola. Major innate immunity mechanisms against Ebola are associated with the production of interferons, that are inhibited by viral proteins. Activation of host NK cells was recognized as a leading immune function responsible for recovery of infected people. Uncontrolled cell infection by Ebola leads to an impairment of immunity with cytokine storm, coagulopathy, systemic bleeding, multi-organ failure and death. Tested prevention strategies to induce antiviral immunity include: i. recombinant virus formulations (vaccines); ii. cocktail of monoclonal antibodies (serotherapy); iii. alternative RNA-interference-based antiviral methods. Maintaining the highest standards of aseptic and antiseptic precautions is equally important. Present brief review summarizes a current knowledge concerning pathogenesis of Ebola hemorrhagic disease and the virus interaction with the immune system and discusses recent advances in prevention of Ebola infection by vaccination and serotherapy.

  18. The first Swedish H1N2 swine influenza virus isolate represents an uncommon reassortant

    Directory of Open Access Journals (Sweden)

    Renström Lena HM

    2009-10-01

    Full Text Available Abstract The European swine influenza viruses (SIVs show considerable diversity comprising different types of H1N1, H3N2, and H1N2 strains. The intensifying full genome sequencing efforts reveal further reassortants within these subtypes. Here we report the identification of an uncommon reassortant variant of H1N2 subtype influenza virus isolated from a pig in a multisite herd where H1N2 swine influenza was diagnosed for the first time in Sweden during the winter of 2008-2009. The majority of the European H1N2 swine influenza viruses described so far possess haemagglutinin (HA of the human-like H1N2 SIV viruses and the neuraminidase (NA of either the European H1N2 or H3N2 SIV-like viruses. The Swedish isolate has an avian-like SIV HA and a H3N2 SIV-like NA, which is phylogenetically more closely related to H3N2 SIV NAs from isolates collected in the early '80s than to the NA of H3N2 origin of the H1N2 viruses isolated during the last decade, as depicted by some German strains, indicative of independent acquisition of the NA genes for these two types of reassortants. The internal genes proved to be entirely of avian-like SIV H1N1 origin. The prevalence of this SIV variant in pig populations needs to be determined, as well as the suitability of the routinely used laboratory reagents to analyze this strain. The description of this H1N2 SIV adds further information to influenza epidemiology and supports the necessity of surveillance for influenza viruses in pigs.

  19. The first Swedish H1N2 swine influenza virus isolate represents an uncommon reassortant.

    Science.gov (United States)

    Bálint, Adám; Metreveli, Giorgi; Widén, Frederik; Zohari, Siamak; Berg, Mikael; Isaksson, Mats; Renström, Lena Hm; Wallgren, Per; Belák, Sándor; Segall, Thomas; Kiss, István

    2009-10-28

    The European swine influenza viruses (SIVs) show considerable diversity comprising different types of H1N1, H3N2, and H1N2 strains. The intensifying full genome sequencing efforts reveal further reassortants within these subtypes. Here we report the identification of an uncommon reassortant variant of H1N2 subtype influenza virus isolated from a pig in a multisite herd where H1N2 swine influenza was diagnosed for the first time in Sweden during the winter of 2008-2009. The majority of the European H1N2 swine influenza viruses described so far possess haemagglutinin (HA) of the human-like H1N2 SIV viruses and the neuraminidase (NA) of either the European H1N2 or H3N2 SIV-like viruses. The Swedish isolate has an avian-like SIV HA and a H3N2 SIV-like NA, which is phylogenetically more closely related to H3N2 SIV NAs from isolates collected in the early '80s than to the NA of H3N2 origin of the H1N2 viruses isolated during the last decade, as depicted by some German strains, indicative of independent acquisition of the NA genes for these two types of reassortants. The internal genes proved to be entirely of avian-like SIV H1N1 origin. The prevalence of this SIV variant in pig populations needs to be determined, as well as the suitability of the routinely used laboratory reagents to analyze this strain.The description of this H1N2 SIV adds further information to influenza epidemiology and supports the necessity of surveillance for influenza viruses in pigs.

  20. A phylogeny-based global nomenclature system and automated annotation tool for H1 hemagglutinin genes from swine influenza A viruses

    Science.gov (United States)

    The H1 subtype of influenza A viruses (IAV) has been circulating in swine since the 1918 human influenza pandemic. Over time, and aided by further introductions from non-swine hosts, swine H1 have diversified into three genetic lineages. Due to limited global data, these H1 lineages were named based...

  1. Yellow Fever Virus Vaccine–associated Deaths in Young Women 1

    OpenAIRE

    Seligman, Stephen J.

    2011-01-01

    Yellow fever vaccine–associated viscerotropic disease is a rare sequela of live-attenuated virus vaccine. Elderly persons and persons who have had thymectomies have increased susceptibility. A review of published and other data suggested a higher than expected number of deaths from yellow fever vaccine–associated viscerotropic disease among women 19–34 years of age without known immunodeficiency.

  2. Lineage-Specific Real-Time RT-PCR for Yellow Fever Virus Outbreak Surveillance, Brazil.

    Science.gov (United States)

    Fischer, Carlo; Torres, Maria C; Patel, Pranav; Moreira-Soto, Andres; Gould, Ernest A; Charrel, Rémi N; de Lamballerie, Xavier; Nogueira, Rita Maria Ribeiro; Sequeira, Patricia C; Rodrigues, Cintia D S; Kümmerer, Beate M; Drosten, Christian; Landt, Olfert; Bispo de Filippis, Ana Maria; Drexler, Jan Felix

    2017-11-01

    The current yellow fever outbreak in Brazil prompted widespread yellow fever virus (YFV) vaccination campaigns, imposing a responsibility to distinguish between vaccine- and wild-type YFV-associated disease. We developed novel multiplex real-time reverse transcription PCRs that differentiate between vaccine and American wild-type YFV. We validated these highly specific and sensitive assays in an outbreak setting.

  3. Lineage-Specific Real-Time RT-PCR for Yellow Fever Virus Outbreak Surveillance, Brazil

    OpenAIRE

    Fischer, Carlo; Torres, Maria C.; Patel, Pranav; Moreira-Soto, Andres; Gould, Ernest A.; Charrel, Rémi N.; de Lamballerie, Xavier; Nogueira, Rita Maria Ribeiro; Sequeira, Patricia C.; Rodrigues, Cintia D.S.; Kümmerer, Beate M.; Drosten, Christian; Landt, Olfert; Bispo de Filippis, Ana Maria; Drexler, Jan Felix

    2017-01-01

    The current yellow fever outbreak in Brazil prompted widespread yellow fever virus (YFV) vaccination campaigns, imposing a responsibility to distinguish between vaccine- and wild-type YFV-associated disease. We developed novel multiplex real-time reverse transcription PCRs that differentiate between vaccine and American wild-type YFV. We validated these highly specific and sensitive assays in an outbreak setting.

  4. A DNA vaccine against yellow fever virus: development and evaluation.

    Directory of Open Access Journals (Sweden)

    Milton Maciel

    2015-04-01

    Full Text Available Attenuated yellow fever (YF virus 17D/17DD vaccines are the only available protection from YF infection, which remains a significant source of morbidity and mortality in the tropical areas of the world. The attenuated YF virus vaccine, which is used worldwide, generates both long-lasting neutralizing antibodies and strong T-cell responses. However, on rare occasions, this vaccine has toxic side effects that can be fatal. This study presents the design of two non-viral DNA-based antigen formulations and the characterization of their expression and immunological properties. The two antigen formulations consist of DNA encoding the full-length envelope protein (p/YFE or the full-length envelope protein fused to the lysosomal-associated membrane protein signal, LAMP-1 (pL/YFE, aimed at diverting antigen processing/presentation through the major histocompatibility complex II precursor compartments. The immune responses triggered by these formulations were evaluated in H2b and H2d backgrounds, corresponding to the C57Bl/6 and BALB/c mice strains, respectively. Both DNA constructs were able to induce very strong T-cell responses of similar magnitude against almost all epitopes that are also generated by the YF 17DD vaccine. The pL/YFE formulation performed best overall. In addition to the T-cell response, it was also able to stimulate high titers of anti-YF neutralizing antibodies comparable to the levels elicited by the 17DD vaccine. More importantly, the pL/YFE vaccine conferred 100% protection against the YF virus in intracerebrally challenged mice. These results indicate that pL/YFE DNA is an excellent vaccine candidate and should be considered for further developmental studies.

  5. A DNA vaccine against yellow fever virus: development and evaluation.

    Science.gov (United States)

    Maciel, Milton; Cruz, Fábia da Silva Pereira; Cordeiro, Marli Tenório; da Motta, Márcia Archer; Cassemiro, Klécia Marília Soares de Melo; Maia, Rita de Cássia Carvalho; de Figueiredo, Regina Célia Bressan Queiroz; Galler, Ricardo; Freire, Marcos da Silva; August, Joseph Thomas; Marques, Ernesto T A; Dhalia, Rafael

    2015-04-01

    Attenuated yellow fever (YF) virus 17D/17DD vaccines are the only available protection from YF infection, which remains a significant source of morbidity and mortality in the tropical areas of the world. The attenuated YF virus vaccine, which is used worldwide, generates both long-lasting neutralizing antibodies and strong T-cell responses. However, on rare occasions, this vaccine has toxic side effects that can be fatal. This study presents the design of two non-viral DNA-based antigen formulations and the characterization of their expression and immunological properties. The two antigen formulations consist of DNA encoding the full-length envelope protein (p/YFE) or the full-length envelope protein fused to the lysosomal-associated membrane protein signal, LAMP-1 (pL/YFE), aimed at diverting antigen processing/presentation through the major histocompatibility complex II precursor compartments. The immune responses triggered by these formulations were evaluated in H2b and H2d backgrounds, corresponding to the C57Bl/6 and BALB/c mice strains, respectively. Both DNA constructs were able to induce very strong T-cell responses of similar magnitude against almost all epitopes that are also generated by the YF 17DD vaccine. The pL/YFE formulation performed best overall. In addition to the T-cell response, it was also able to stimulate high titers of anti-YF neutralizing antibodies comparable to the levels elicited by the 17DD vaccine. More importantly, the pL/YFE vaccine conferred 100% protection against the YF virus in intracerebrally challenged mice. These results indicate that pL/YFE DNA is an excellent vaccine candidate and should be considered for further developmental studies.

  6. A DNA Vaccine against Yellow Fever Virus: Development and Evaluation

    Science.gov (United States)

    Maciel, Milton; Cruz, Fábia da Silva Pereira; Cordeiro, Marli Tenório; da Motta, Márcia Archer; Cassemiro, Klécia Marília Soares de Melo; Maia, Rita de Cássia Carvalho; de Figueiredo, Regina Célia Bressan Queiroz; Galler, Ricardo; Freire, Marcos da Silva; August, Joseph Thomas; Marques, Ernesto T. A.; Dhalia, Rafael

    2015-01-01

    Attenuated yellow fever (YF) virus 17D/17DD vaccines are the only available protection from YF infection, which remains a significant source of morbidity and mortality in the tropical areas of the world. The attenuated YF virus vaccine, which is used worldwide, generates both long-lasting neutralizing antibodies and strong T-cell responses. However, on rare occasions, this vaccine has toxic side effects that can be fatal. This study presents the design of two non-viral DNA-based antigen formulations and the characterization of their expression and immunological properties. The two antigen formulations consist of DNA encoding the full-length envelope protein (p/YFE) or the full-length envelope protein fused to the lysosomal-associated membrane protein signal, LAMP-1 (pL/YFE), aimed at diverting antigen processing/presentation through the major histocompatibility complex II precursor compartments. The immune responses triggered by these formulations were evaluated in H2b and H2d backgrounds, corresponding to the C57Bl/6 and BALB/c mice strains, respectively. Both DNA constructs were able to induce very strong T-cell responses of similar magnitude against almost all epitopes that are also generated by the YF 17DD vaccine. The pL/YFE formulation performed best overall. In addition to the T-cell response, it was also able to stimulate high titers of anti-YF neutralizing antibodies comparable to the levels elicited by the 17DD vaccine. More importantly, the pL/YFE vaccine conferred 100% protection against the YF virus in intracerebrally challenged mice. These results indicate that pL/YFE DNA is an excellent vaccine candidate and should be considered for further developmental studies. PMID:25875109

  7. Infection of Mosquito Cells (C6/36) by Dengue-2 Virus Interferes with Subsequent Infection by Yellow Fever Virus.

    Science.gov (United States)

    Abrao, Emiliana Pereira; da Fonseca, Benedito Antônio Lopes

    2016-02-01

    Dengue is one of the most important diseases caused by arboviruses in the world. Yellow fever is another arthropod-borne disease of great importance to public health that is endemic to tropical regions of Africa and the Americas. Both yellow fever and dengue viruses are flaviviruses transmitted by Aedes aegypti mosquitoes, and then, it is reasonable to consider that in a given moment, mosquito cells could be coinfected by both viruses. Therefore, we decided to evaluate if sequential infections of dengue and yellow fever viruses (and vice-versa) in mosquito cells could affect the virus replication patterns. Using immunofluorescence and real-time PCR-based replication assays in Aedes albopictus C6/36 cells with single or sequential infections with both viruses, we demonstrated the occurrence of viral interference, also called superinfection exclusion, between these two viruses. Our results show that this interference pattern is particularly evident when cells were first infected with dengue virus and subsequently with yellow fever virus (YFV). Reduction in dengue virus replication, although to a lower extent, was also observed when C6/36 cells were initially infected with YFV followed by dengue virus infection. Although the importance that these findings have on nature is unknown, this study provides evidence, at the cellular level, of the occurrence of replication interference between dengue and yellow fever viruses and raises the question if superinfection exclusion could be a possible explanation, at least partially, for the reported lack of urban yellow fever occurrence in regions where a high level of dengue transmission occurs.

  8. Coronavirus in Pigs: Significance and Presentation of Swine Epidemic Diarrhea Virus (PEDV in Colombia

    Directory of Open Access Journals (Sweden)

    Ricardo Piñeros

    2015-05-01

    Full Text Available The article seeks to study general aspects of the main coronaviruses affecting pigs, their presentation in Colombia, and particular aspects of porcine epidemic diarrhea virus (PEDV, emerging in different countries and generating a great impact on the health and economy of the swine industry. The main coronaviruses affecting swine are porcine transmissible gastroenteritis virus (TGEV, porcine respiratory coronavirus (PRCV, porcine hemagglutinating encephalomyelitis virus (PHEV, PEDV, and porcine deltacoronavirus (PDCoV. Long ago in Colombia there had been reports of TGEV and PRCV associated with the importation of animals from the United States, which was controlled in the infected farms and in quarantine units. PEDV was first detected in Colombia in mid-March 2014; the Colombian Agricultural Institute issued a health alert in Neiva (Huila, Fusagasugá and Silvania (Cundinamarca, and Puerto López (Meta due to the unusual presentation of epidemic vomiting and diarrhea in young and adult animals, abortion in pregnant sows, with high mortality rates (up to 100% in animals during the first week of age. At present the disease has been reported in other municipalities of the country as well as in different countries with similar clinical conditions and mortality rates in pigs with high economic losses for the swine sector.

  9. New reassortant and enzootic European swine influenza viruses transmit efficiently through direct contact in the ferret model.

    Science.gov (United States)

    Fobian, Kristina; Fabrizio, Thomas P; Yoon, Sun-Woo; Hansen, Mette Sif; Webby, Richard J; Larsen, Lars E

    2015-07-01

    The reverse zoonotic events that introduced the 2009 pandemic influenza virus into pigs have drastically increased the diversity of swine influenza viruses in Europe. The pandemic potential of these novel reassortments is still unclear, necessitating enhanced surveillance of European pigs with additional focus on risk assessment of these new viruses. In this study, four European swine influenza viruses were assessed for their zoonotic potential. Two of the four viruses were enzootic viruses of subtype H1N2 (with avian-like H1) and H3N2, and two were new reassortants, one with avian-like H1 and human-like N2 and one with 2009 pandemic H1 and swine-like N2. All viruses replicated to high titres in nasal wash and nasal turbinate samples from inoculated ferrets and transmitted efficiently by direct contact. Only the H3N2 virus transmitted to naïve ferrets via the airborne route. Growth kinetics using a differentiated human bronchial epithelial cell line showed that all four viruses were able to replicate to high titres. Further, the viruses revealed preferential binding to the 2,6-α-silalylated glycans and investigation of the antiviral susceptibility of the viruses revealed that all were sensitive to neuraminidase inhibitors. These findings suggested that these viruses have the potential to infect humans and further underline the need for continued surveillance as well as biological characterization of new influenza A viruses.

  10. Evolutionary and molecular analysis of the emergent severe fever with thrombocytopenia syndrome virus

    OpenAIRE

    Lam, Tommy Tsan-Yuk; Liu, Wei; Bowden, Thomas A.; Cui, Ning; Zhuang, Lu; Liu, Kun; Zhang, Yao-Yun; Cao, Wu-Chun; Pybus, Oliver G.

    2013-01-01

    In 2009, a novel Bunyavirus, called severe fever with thrombocytopenia syndrome virus (SFTSV) was identified in the vicinity of Huaiyangshan, China. Clinical symptoms of this zoonotic virus included severe fever, thrombocytopenia, and leukocytopenia, with a mortality rate of ?10%. By the end of 2011 the disease associated with this pathogen had been reported from eleven Chinese provinces and human-to-human transmission suspected. However, current understanding of the evolution and molecular e...

  11. Evidence for Cross-species Influenza A Virus Transmission Within Swine Farms, China: A One Health, Prospective Cohort Study.

    Science.gov (United States)

    Ma, Mai-Juan; Wang, Guo-Lin; Anderson, Benjamin D; Bi, Zhen-Qiang; Lu, Bing; Wang, Xian-Jun; Wang, Chuang-Xin; Chen, Shan-Hui; Qian, Yan-Hua; Song, Shao-Xia; Li, Min; Lednicky, John A; Zhao, Teng; Wu, Meng-Na; Cao, Wu-Chun; Gray, Gregory C

    2018-02-01

    Our understanding of influenza A virus transmission between humans and pigs is limited. Beginning in 2015, we used a One Health approach and serial sampling to prospectively study 299 swine workers and 100 controls, their 9000 pigs, and 6 pig farm environments in China for influenza A viruses (IAVs) using molecular, culture, and immunological techniques. Study participants were closely monitored for influenza-like illness (ILI) events. Upon enrollment, swine workers had higher serum neutralizing antibody titers against swine H1N1 and higher nasal wash total immunoglobulin A (IgA) and specific IgA titers against swine H1N1 and H3N2 viruses. Over a period of 12 months, IAVs were detected by quantitative reverse-transcription polymerase chain reaction in 46 of 396 (11.6%) environmental swabs, 235 of 3300 (7.1%) pig oral secretion, 23 of 396 (5.8%) water, 20 of 396 (5.1%) aerosol, and 19 of 396 (4.8%) fecal-slurry specimens. Five of 32 (15.6%) participants with ILI events had nasopharyngeal swab specimens that were positive for IAV, and 17 (53.1%) demonstrated 4-fold rises in neutralization titers against a swine virus. Reassorted Eurasian avian-lineage H1N1, A(H1N1)pdm09-like, and swine-lineage H3N2 viruses were identified in pig farms. The A(H1N1)pdm09-like H1N1 viruses identified in swine were nearly genetically identical to the human H1N1 viruses isolated from the participants with ILI. There was considerable evidence of A(H1N1)pdm09-like, swine-lineage H1N1, and swine-lineage H3N2 viruses circulating, likely reassorting, and likely crossing species within the pig farms. These data suggest that stronger surveillance for novel influenza virus emergence within swine farms is imperative. © The Author(s) 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  12. Rift Valley fever virus MP-12 vaccine encoding Toscana virus NSs retains neuroinvasiveness in mice.

    Science.gov (United States)

    Indran, Sabarish V; Lihoradova, Olga A; Phoenix, Inaia; Lokugamage, Nandadeva; Kalveram, Birte; Head, Jennifer A; Tigabu, Bersabeh; Smith, Jennifer K; Zhang, Lihong; Juelich, Terry L; Gong, Bin; Freiberg, Alexander N; Ikegami, Tetsuro

    2013-07-01

    Rift Valley fever is a mosquito-borne zoonotic disease endemic to sub-Saharan Africa. Rift Valley fever virus (RVFV; genus Phlebovirus, family Bunyaviridae) causes high rates of abortion and fetal malformation in pregnant ruminants, and haemorrhagic fever, neurological disorders or blindness in humans. The MP-12 strain is a highly efficacious and safe live-attenuated vaccine candidate for both humans and ruminants. However, MP-12 lacks a marker to differentiate infected from vaccinated animals. In this study, we originally aimed to characterize the efficacy of a recombinant RVFV MP-12 strain encoding Toscana virus (TOSV) NSs gene in place of MP-12 NSs (rMP12-TOSNSs). TOSV NSs promotes the degradation of dsRNA-dependent protein kinase (PKR) and inhibits interferon-β gene up-regulation without suppressing host general transcription. Unexpectedly, rMP12-TOSNSs increased death in vaccinated outbred mice and inbred BALB/c or C57BL/6 mice. Immunohistochemistry showed diffusely positive viral antigens in the thalamus, hypothalamus and brainstem, including the medulla. No viral antigens were detected in spleen or liver, which is similar to the antigen distribution of moribund mice infected with MP-12. These results suggest that rMP12-TOSNSs retains neuroinvasiveness in mice. Our findings demonstrate that rMP12-TOSNSs causes neuroinvasion without any hepatic disease and will be useful for studying the neuroinvasion mechanism of RVFV and TOSV.

  13. The Inability to Screen Exhibition Swine for Influenza A Virus Using Body Temperature.

    Science.gov (United States)

    Bowman, A S; Nolting, J M; Workman, J D; Cooper, M; Fisher, A E; Marsh, B; Forshey, T

    2016-02-01

    Agricultural fairs create an unconventional animal-human interface that has been associated with swine-to-human transmission of influenza A virus (IAV) in recent years. Early detection of IAV-infected pigs at agricultural fairs would allow veterinarians to better protect swine and human health during these swine exhibitions. This study assessed the use of swine body temperature measurement, recorded by infrared and rectal thermometers, as a practical method to detect IAV-infected swine at agricultural fairs. In our first objective, infrared thermometers were used to record the body surface temperature of 1,092 pigs at the time of IAV nasal swab collection at the end of the exhibition period of 55 agricultural fairs. IAV was recovered from 212 (19.4%) pigs, and the difference in mean infrared body temperature measurement of IAV-positive and IAV-negative pigs was 0.83°C. In a second objective, snout wipes were collected from 1,948 pigs immediately prior to the unloading of the animals at a single large swine exhibition. Concurrent to the snout wipe collection, owners took the rectal temperatures of his/her pigs. In this case, 47 (2.4%) pigs tested positive for IAV before they entered the swine barn. The mean rectal temperatures differed by only 0.19°C between IAV-positive and IAV-negative pigs. The low prevalence of IAV among the pigs upon entry to the fair in the second objective provides evidence that limiting intraspecies spread of IAV during the fairs will likely have significant impacts on the zoonotic transmission. However, in both objectives, the high degree of similarity in the body temperature measurements between the IAV-positive and IAV-negative pigs made it impossible to set a diagnostically meaningful cut point to differentiate IAV status of the individual animals. Unfortunately, body temperature measurement cannot be used to accurately screen exhibition swine for IAV. © 2015 Blackwell Verlag GmbH.

  14. Modified vaccinia virus Ankara expressing the hemagglutinin of pandemic (H1N1) 2009 virus induces cross-protective immunity against Eurasian 'avian-like' H1N1 swine viruses in mice.

    Science.gov (United States)

    Castrucci, Maria R; Facchini, Marzia; Di Mario, Giuseppina; Garulli, Bruno; Sciaraffia, Ester; Meola, Monica; Fabiani, Concetta; De Marco, Maria A; Cordioli, Paolo; Siccardi, Antonio; Kawaoka, Yoshihiro; Donatelli, Isabella

    2014-05-01

    To examine cross-reactivity between hemagglutinin (HA) derived from A/California/7/09 (CA/09) virus and that derived from representative Eurasian "avian-like" (EA) H1N1 swine viruses isolated in Italy between 1999 and 2008 during virological surveillance in pigs. Modified vaccinia virus Ankara (MVA) expressing the HA gene of CA/09 virus (MVA-HA-CA/09) was used as a vaccine to investigate cross-protective immunity against H1N1 swine viruses in mice. Two classical swine H1N1 (CS) viruses and four representative EA-like H1N1 swine viruses previously isolated during outbreaks of respiratory disease in pigs on farms in Northern Italy were used in this study. Female C57BL/6 mice were vaccinated with MVA/HA/CA/09 and then challenged intranasally with H1N1 swine viruses. Cross-reactive antibody responses were determined by hemagglutination- inhibition (HI) and virus microneutralizing (MN) assays of sera from MVA-vaccinated mice. The extent of protective immunity against infection with H1N1 swine viruses was determined by measuring lung viral load on days 2 and 4 post-challenge. Systemic immunization of mice with CA/09-derived HA, vectored by MVA, elicited cross-protective immunity against recent EA-like swine viruses. This immune protection was related to the levels of cross-reactive HI antibodies in the sera of the immunized mice and was dependent on the similarity of the antigenic site Sa of H1 HAs. Our findings suggest that the herd immunity elicited in humans by the pandemic (H1N1) 2009 virus could limit the transmission of recent EA-like swine HA genes into the influenza A virus gene pool in humans. © 2013 The Authors Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

  15. Optimal Use of Vaccines for Control of Influenza A Virus in Swine

    Directory of Open Access Journals (Sweden)

    Matthew R. Sandbulte

    2015-01-01

    Full Text Available Influenza A virus in swine (IAV-S is one of the most important infectious disease agents of swine in North America. In addition to the economic burden of IAV-S to the swine industry, the zoonotic potential of IAV-S sometimes leads to serious public health concerns. Adjuvanted, inactivated vaccines have been licensed in the United States for over 20 years, and there is also widespread usage of autogenous/custom IAV-S vaccines. Vaccination induces neutralizing antibodies and protection against infection with very similar strains. However, IAV-S strains are so diverse and prone to mutation that these vaccines often have disappointing efficacy in the field. This scientific review was developed to help veterinarians and others to identify the best available IAV-S vaccine for a particular infected herd. We describe key principles of IAV-S structure and replication, protective immunity, currently available vaccines, and vaccine technologies that show promise for the future. We discuss strategies to optimize the use of available IAV-S vaccines, based on information gathered from modern diagnostics and surveillance programs. Improvements in IAV-S immunization strategies, in both the short term and long term, will benefit swine health and productivity and potentially reduce risks to public health.

  16. T Cell-Mediated Immunity towards Yellow Fever Virus and Useful Animal Models.

    Science.gov (United States)

    Watson, Alan M; Klimstra, William B

    2017-04-11

    The 17D line of yellow fever virus vaccines is among the most effective vaccines ever created. The humoral and cellular immunity elicited by 17D has been well characterized in humans. Neutralizing antibodies have long been known to provide protection against challenge with a wild-type virus. However, a well characterized T cell immune response that is robust, long-lived and polyfunctional is also elicited by 17D. It remains unclear whether this arm of immunity is protective following challenge with a wild-type virus. Here we introduce the 17D line of yellow fever virus vaccines, describe the current state of knowledge regarding the immunity directed towards the vaccines in humans and conclude with a discussion of animal models that are useful for evaluating T cell-mediated immune protection to yellow fever virus.

  17. T Cell-Mediated Immunity towards Yellow Fever Virus and Useful Animal Models

    Science.gov (United States)

    Watson, Alan M.; Klimstra, William B.

    2017-01-01

    The 17D line of yellow fever virus vaccines is among the most effective vaccines ever created. The humoral and cellular immunity elicited by 17D has been well characterized in humans. Neutralizing antibodies have long been known to provide protection against challenge with a wild-type virus. However, a well characterized T cell immune response that is robust, long-lived and polyfunctional is also elicited by 17D. It remains unclear whether this arm of immunity is protective following challenge with a wild-type virus. Here we introduce the 17D line of yellow fever virus vaccines, describe the current state of knowledge regarding the immunity directed towards the vaccines in humans and conclude with a discussion of animal models that are useful for evaluating T cell-mediated immune protection to yellow fever virus. PMID:28398253

  18. The PB2-K627E mutation attenuates H3N2 swine influenza virus in cultured cells and in mice.

    Science.gov (United States)

    Gong, Xiao-Qian; Ruan, Bao-Yang; Liu, Xiao-Min; Zhang, Peng; Wang, Xiu-Hui; Wang, Qi; Shan, Tong-Ling; Tong, Wu; Zhou, Yan-Jun; Li, Guo-Xin; Zheng, Hao; Tong, Guang-Zhi; Yu, Hai

    2018-04-01

    PB2-627K is an important amino acid that determines the virulence of some influenza A viruses. However, it has not been experimentally investigated in the H3N2 swine influenza virus. To explore the potential role of PB2-K627E substitution in H3N2 swine influenza virus, the growth properties and pathogenicity between H3N2 swine influenza virus and its PB2-K627E mutant were compared. For the first time, our results showed that PB2-K627E mutation attenuates H3N2 swine influenza virus in mammalian cells and in mice, suggesting that PB2-627K is required for viral replication and pathogenicity of H3N2 swine influenza virus. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. In vitro reassortment between endemic H1N2 and 2009 H1N1 pandemic swine influenza viruses generates attenuated viruses.

    Directory of Open Access Journals (Sweden)

    Ben M Hause

    Full Text Available The pandemic H1N1 (pH1N1 influenza virus was first reported in humans in the spring of 2009 and soon thereafter was identified in numerous species, including swine. Reassortant viruses, presumably arising from the co-infection of pH1N1 and endemic swine influenza virus (SIV, were subsequently identified from diagnostic samples collected from swine. In this study, co-infection of swine testicle (ST cells with swine-derived endemic H1N2 (MN745 and pH1N1 (MN432 yielded two reassortant H1N2 viruses (R1 and R2, both possessing a matrix gene derived from pH1N1. In ST cells, the reassortant viruses had growth kinetics similar to the parental H1N2 virus and reached titers approximately 2 log(10 TCID(50/mL higher than the pH1N1 virus, while in A549 cells these viruses had similar growth kinetics. Intranasal challenge of pigs with H1N2, pH1N1, R1 or R2 found that all viruses were capable of infecting and transmitting between direct contact pigs as measured by real time reverse transcription PCR of nasal swabs. Lung samples were also PCR-positive for all challenge groups and influenza-associated microscopic lesions were detected by histology. Interestingly, infectious virus was detected in lung samples for pigs challenged with the parental H1N2 and pH1N1 at levels significantly higher than either reassortant virus despite similar levels of viral RNA. Results of our experiment suggested that the reassortant viruses generated through in vitro cell culture system were attenuated without gaining any selective growth advantage in pigs over the parental lineages. Thus, reassortant influenza viruses described in this study may provide a good system to study genetic basis of the attenuation and its mechanism.

  20. Seroprevalence of sandfly fever virus infection in military personnel on the western border of Iran

    Directory of Open Access Journals (Sweden)

    Ramin Shiraly

    2017-01-01

    Full Text Available Summary: Military troops deployed to endemic areas are at risk of contracting sandfly fever, an arthropod-borne viral infection. Although typically a self-limited disease, sandfly fever can cause significant morbidity and loss of function among soldiers. We conducted this study to determine the extent of past SFV infection in a group of healthy Iranian military personnel in Ilam province on the western border of Iran. A total of 201 serum samples were tested by indirect immunofluorescence assay (IFA to detect four common sandfly fever virus serotypes. Demographic data were also collected. Overall, 37 samples (18.4% were positive for specific IgG antibodies to sandfly viruses. Sandfly fever Sicilian virus (SFSV and sandfly fever Naples virus (SFNV were the most common serotypes. A positive test was inversely related to nativity (P < 0.01 but was not associated with age (P = 0.163, duration of presence in the border region (P = 0.08 or employment status (P = 0.179.Our findings indicate that past SFV infection is common among military personnel in the western border region of Iran, a Leishmania-endemic region. Therefore, it should be considered in the differential diagnosis of troops presenting with acute febrile illness in similar settings. Keywords: Sandfly fever, Virus, Past infection, Military personnel

  1. Detection of Genotype 4 Swine Hepatitis E Virus in Systemic Tissues in Cross-Species Infected Rabbits

    OpenAIRE

    Wu, Qiaoxing; An, Junqing; She, Ruiping; Shi, Ruihan; Hao, Wenzhuo; Soomro, MajidHussain; Yuan, Xuerui; Yang, Jinling; Wang, Jingyuan

    2017-01-01

    Increasing evidence demonstrates that hepatitis E virus (HEV) can be transmitted across species. According to previous reports, swine HEV has two genotypes, genotype 3 and 4, and both can infect humans by the fecal-oral route. Thus, it is crucial for the control of HEV zoonotic transmission to evaluate the dynamics of viral shedding and distribution in different tissues during cross-species infection by HEV. In this study, rabbits were infected with genotype 4 swine HEV by the intraperitoneal...

  2. Shedding of Japanese Encephalitis Virus in Oral Fluid of Infected Swine.

    Science.gov (United States)

    Lyons, Amy C; Huang, Yan-Jang S; Park, So Lee; Ayers, Victoria B; Hettenbach, Susan M; Higgs, Stephen; McVey, D Scott; Noronha, Leela; Hsu, Wei-Wen; Vanlandingham, Dana L

    2018-05-09

    Japanese encephalitis virus (JEV) is a zoonotic mosquito-borne flavivirus endemic in the Asia-Pacific region. Maintenance of JEV in nature involves enzootic transmission by competent Culex mosquitoes among susceptible avian and swine species. Historically, JEV has been regarded as one of the most important arthropod-borne viruses in Southeast Asia. Oronasal shedding of JEV from infected amplification hosts was not recognized until the recent discovery of vector-free transmission of JEV among domestic pigs. In this study, oral shedding of JEV was characterized in domestic pigs and miniature swine representing the feral phenotype. A rope-based sampling method followed by the detection of viral RNA using RT-qPCR allowed the collection and detection of JEV in oral fluid samples collected from intradermally challenged animals. The results suggest that the shedding of JEV in oral fluid can be readily detected by molecular diagnostic assays at the acute phase of infection. It also demonstrates the feasibility of this technique for the diagnosis and surveillance of JEV in swine species.

  3. Risk of African swine fever introduction into the European Union through transport-associated routes: returning trucks and waste from international ships and planes.

    Science.gov (United States)

    Mur, Lina; Martínez-López, Beatriz; Sánchez-Vizcaíno, José Manuel

    2012-08-30

    The uncontrolled presence of African swine fever (ASF) in Russian Federation (RF) poses a serious risk to the whole European Union (EU) pig industry. Although trade of pigs and their products is banned since the official notification in June 2007, the potential introduction of ASF virus (ASFV) may occur by other routes, which are very frequent in ASF, and more difficult to control, such as contaminated waste or infected vehicles. This study was intended to estimate the risk of ASFV introduction into the EU through three types of transport routes: returning trucks, waste from international ships and waste from international planes, which will be referred here as transport-associated routes (TAR). Since no detailed and official information was available for these routes, a semi-quantitative model based on the weighted combination of risk factors was developed to estimate the risk of ASFV introduction by TAR. Relative weights for combination of different risk factors as well as validation of the model results were obtained by an expert opinion elicitation. Model results indicate that the relative risk for ASFV introduction through TAR in most of the EU countries (16) is low, although some countries, specifically Poland and Lithuania, concentrate high levels of risk, the returning trucks route being the analyzed TAR that currently poses the highest risk for ASFV introduction into the EU. The spatial distribution of the risk of ASFV introduction varies importantly between the analyzed introduction routes. Results also highlight the need to increase the awareness and precautions for ASF prevention, particularly ensuring truck disinfection, to minimize the potential risk of entrance into the EU. This study presents the first assessment of ASF introduction into the EU through TAR. The innovative model developed here could be used in data scarce situations for estimating the relative risk associated to each EU country. This simple methodology provides a rapid and easy to

  4. Modeling the Effects of Duration and Size of the Control Zones on the Consequences of a Hypothetical African Swine Fever Epidemic in Denmark

    Science.gov (United States)

    Halasa, Tariq; Bøtner, Anette; Mortensen, Sten; Christensen, Hanne; Wulff, Sisse Birk; Boklund, Anette

    2018-01-01

    African swine fever (ASF) is a notifiable infectious disease. The disease is endemic in certain regions in Eastern Europe constituting a risk of ASF spread toward Western Europe. Therefore, as part of contingency planning, it is important to continuously explore strategies that can effectively control an epidemic of ASF. A previously published and well documented simulation model for ASF virus spread between herds was used to examine the epidemiologic and economic impacts of the duration and size of the control zones around affected herds. In the current study, scenarios were run, where the duration of the protection and surveillance zones were reduced from 50 and 45 days to 35 and 25 days or to 35 and 25 days, respectively. These scenarios were run with or without enlargement of the surveillance zone around detected herds from 10 to 15 km. The scenarios were also run with only clinical or clinical and serological surveillance of herds within the zones. Sensitivity analysis was conducted on influential input parameters in the model. The model predicts that reducing the duration of the protection and surveillance zones has no impact on the epidemiological consequences of the epidemics, while it may result in a substantial reduction in the total economic losses. In addition, the model predicts that increasing the size of the surveillance zone from 10 to 15 km may reduce both the epidemic duration and the total economic losses, in case of large epidemics. The ranking of the control strategies by the total costs of the epidemics was not influenced by changes of input parameters in the sensitivity analyses. PMID:29616228

  5. New insights on the management of wildlife diseases using multi-state recapture models: the case of classical swine fever in wild boar.

    Science.gov (United States)

    Rossi, Sophie; Toigo, Carole; Hars, Jean; Pol, Françoise; Hamann, Jean-Luc; Depner, Klaus; Le Potier, Marie-Frederique

    2011-01-01

    The understanding of host-parasite systems in wildlife is of increasing interest in relation to the risk of emerging diseases in livestock and humans. In this respect, many efforts have been dedicated to controlling classical swine fever (CSF) in the European Wild Boar. But CSF eradication has not always been achieved even though vaccination has been implemented at a large-scale. Piglets have been assumed to be the main cause of CSF persistence in the wild since they appeared to be more often infected and less often immune than older animals. However, this assumption emerged from laboratory trials or cross-sectional surveys based on the hunting bags. In the present paper we conducted a capture-mark-recapture study in free-ranging wild boar piglets that experienced both CSF infection and vaccination under natural conditions. We used multi-state capture recapture models to estimate the immunization and infection rates, and their variations according to the periods with or without vaccination. According to the model prediction, 80% of the infected piglets did not survive more than two weeks, while the other 20% quickly recovered. The probability of becoming immune did not increase significantly during the summer vaccination sessions, and the proportion of immune piglets was not higher after the autumn vaccination. Given the high lethality of CSF in piglets highlighted in our study, we consider unlikely that piglets could maintain the chain of CSF virus transmission. Our study also revealed the low efficacy of vaccination in piglets in summer and autumn, possibly due to the low palatability of baits to that age class, but also to the competition between baits and alternative food sources. Based on this new information, we discuss the prospects for the improvement of CSF control and the interest of the capture-recapture approach for improving the understanding of wildlife diseases.

  6. Genetic drift of HA and NA in Danish swine influenza virus from the period 2003-2012

    DEFF Research Database (Denmark)

    Fobian, Kristina; Breum, Solvej Østergaard; Hjulsager, Charlotte Kristiane

    2012-01-01

    . Currently at least three influenza A subtypes (H1N1, H1N2 and H3N2) are endemic in the Danish swine population, and since 2010 the pandemic virus (H1N1pdm09) have also frequently been detected. The focus in this study will be on H1N1 and H1N2, since the prevalence of H3N2 have declined over the past years...... will provide a more complete picture of the molecular epidemiology of the H1N1 and H1N2 swine influenza viruses in Denmark. A thorough knowledge of the antigenic drift in surface genes is very important concerning evaluation of the zoonotic potential of existing and future swine influenza virus strains......The aim of this study is to analyze; the genetic drift in hemagglutinin (HA) and neuraminidase (NA) genes from influenza viruses isolated from Danish swine over the past decade; the antigenic evolution and relatedness between swine influenza virus strains of the H1 subtype by antigenic cartography...

  7. Two different genotypes of H1N2 swine influenza virus isolated in northern China and their pathogenicity in animals.

    Science.gov (United States)

    Yang, Huanliang; Chen, Yan; Qiao, Chuanling; Xu, Chuantian; Yan, Minghua; Xin, Xiaoguang; Bu, Zhigao; Chen, Hualan

    2015-02-25

    During 2006 and 2007, two swine-origin triple-reassortant influenza A (H1N2) viruses were isolated from pigs in northern China, and the antigenic characteristics of the hemagglutinin protein of the viruses were examined. Genotyping and phylogenetic analyses demonstrated different emergence patterns for the two H1N2 viruses, Sw/Hebei/10/06 and Sw/Tianjin/1/07. Sequences for the other genes encoding the internal proteins were compared with the existing data to determine their origins and establish the likely mechanisms of genetic reassortment. Sw/Hebei/10/06 is an Sw/Indiana/9K035/99-like virus, whereas Sw/Tianjin/1/07 represents a new H1N2 genotype with surface genes of classic swine and human origin and internal genes originating from the Eurasian avian-like swine H1N1 virus. Six-week-old female BALB/c mice infected with the Sw/HeB/10/06 and Sw/TJ/1/07 viruses showed an average weight loss of 12.8% and 8.1%, respectively. Healthy six-week-old pigs were inoculated intranasally with either the Sw/HeB/10/06 or Sw/TJ/1/07 virus. No considerable changes in the clinical presentation were observed post-inoculation in any of the virus-inoculated groups, and the viruses effectively replicated in the nasal cavity and lung tissue. Based on the results, it is possible that the new genotype of the swine H1N2 virus that emerged in China may become widespread in the swine population and pose a potential threat to public health. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Hepatitis E Virus (Genotype 3) in Slurry Samples from Swine Farming Activities in Italy.

    Science.gov (United States)

    La Rosa, G; Della Libera, S; Brambilla, M; Bisaglia, C; Pisani, G; Ciccaglione, A R; Bruni, R; Taffon, S; Equestre, M; Iaconelli, M

    2017-06-01

    Hepatitis E virus (HEV) is an emergent causative agent of acute hepatitis, transmitted by fecal-oral route. Infection with HEV is a global cause for morbidity and mortality throughout the world: it mainly causes large outbreaks in endemic areas and sporadic autochthonous cases in industrialized countries where HEV infections seem to be an emergent zoonotic disease. Infection of porcine livestock and its relationship with the human cases have been demonstrated. The present study describes an investigation on the prevalence and diversity of HEV in pig slurry in Italy. Slurry samples (24) were collected from ten farms located in North Italy during 2015 and analyzed for HEV, using four broad-range nested PCR assays targeting ORF1 (MTase), ORF2 (capsid) genes, and ORF2/3 regions. Overall, 18 samples (75%) were positive for HEV RNA, and characterized as genotype 3. Nine samples could be subtyped by ORF2 sequencing: Eight belonged to subtype 3f, while one sequence could not be characterized by blast analysis and phylogenetic analysis and may actually represent a new subtype. Furthermore, similarity of 99% was found between 3f Italian HEV sequences of human and swine origins. Real-Time PCR assay was also performed, in order to obtain quantitative data on positive samples. Two swine slurry samples were positive, containing 600 and 1000 UI per mL of sewage. The results of this study show that HEV strains belonging to zoonotic genotype 3 are widely present in swine excreta, and have high degree of identity with strains detected in autochthonous HEV cases. Improving swine farming operations safety and increasing operators' awareness of the zoonotic potential connected with the handling of swine effluents turn out to be key points in order to reduce the environmental and sanitary problem represented by the possible dissemination of HEV to water bodies.

  9. Virulence and transmissibility of H1N2 influenza virus in ferrets imply the continuing threat of triple-reassortant swine viruses.

    Science.gov (United States)

    Pascua, Philippe Noriel Q; Song, Min-Suk; Lee, Jun Han; Baek, Yun Hee; Kwon, Hyeok-il; Park, Su-Jin; Choi, Eun Hye; Lim, Gyo-Jin; Lee, Ok-Jun; Kim, Si-Wook; Kim, Chul-Joong; Sung, Moon Hee; Kim, Myung Hee; Yoon, Sun-Woo; Govorkova, Elena A; Webby, Richard J; Webster, Robert G; Choi, Young-Ki

    2012-09-25

    Efficient worldwide swine surveillance for influenza A viruses is urgently needed; the emergence of a novel reassortant pandemic H1N1 (pH1N1) virus in 2009 demonstrated that swine can be the direct source of pandemic influenza and that the pandemic potential of viruses prevalent in swine populations must be monitored. We used the ferret model to assess the pathogenicity and transmissibility of predominant Korean triple-reassortant swine (TRSw) H1N2 and H3N2 influenza viruses genetically related to North American strains. Although most of the TRSw viruses were moderately pathogenic, one [A/Swine/Korea/1204/2009; Sw/1204 (H1N2)] was virulent in ferrets, causing death within 10 d of inoculation, and was efficiently transmitted to naive contact ferrets via respiratory droplets. Although molecular analysis did not reveal known virulence markers, the Sw/1204 virus acquired mutations in hemagglutinin (HA) (Asp-225-Gly) and neuraminidase (NA) (Ser-315-Asn) proteins during the single ferret passage. The contact-Sw/1204 virus became more virulent in mice, replicated efficiently in vitro, extensively infected human lung tissues ex vivo, and maintained its ability to replicate and transmit in swine. Reverse-genetics studies further indicated that the HA(225G) and NA(315N) substitutions contributed substantially in altering virulence and transmissibility. These findings support the continuing threat of some field TRSw viruses to human and animal health, reviving concerns on the capacity of pigs to create future pandemic viruses. Apart from warranting continued and enhanced global surveillance, this study also provides evidence on the emerging roles of HA(225G) and NA(315N) as potential virulence markers in mammals.

  10. Acid-activated structural reorganization of the Rift Valley fever virus Gc fusion protein

    NARCIS (Netherlands)

    Boer, de S.M.; Kortekaas, J.A.; Spel, L.; Rottier, P.J.M.; Moormann, R.J.M.; Bosch, B.J.

    2012-01-01

    Entry of the enveloped Rift Valley fever virus (RVFV) into its host cell is mediated by the viral glycoproteins Gn and Gc. We investigated the RVFV entry process and its pH-dependent activation mechanism in particular using our recently developed nonspreading RVFV particle system. Entry of the virus

  11. Transmission of Rift Valley fever virus from European-breed lambs to Culex pipiens mosquitoes

    NARCIS (Netherlands)

    Vloet, Rianka P.M.; Vogels, Chantal B.F.; Koenraadt, Constantianus J.M.; Pijlman, Gorben P.; Eiden, Martin; Gonzales, Jose L.; Keulen, van Lucien J.M.; Wichgers Schreur, Paul J.; Kortekaas, Jeroen

    2017-01-01

    Background: Rift Valley fever virus (RVFV) is a mosquito-borne bunyavirus of the genus Phlebovirus that is highly pathogenic to ruminants and humans. The disease is currently confined to Africa and the Arabian Peninsula, but globalization and climate change may facilitate introductions of the virus

  12. Real-time laboratory exercises to test contingency plans for classical swine fever: experiences from two national laboratories.

    Science.gov (United States)

    Koenen, F; Uttenthal, A; Meindl-Böhmer, A

    2007-12-01

    In order to adequately and efficiently handle outbreaks of contagious diseases such as classical swine fever (CSF), foot and mouth disease or highly pathogenic avian influenza, competent authorities and the laboratories involved have to be well prepared and must be in possession of functioning contingency plans. These plans should ensure that in the event of an outbreak access to facilities, equipment, resources, trained personnel, and all other facilities needed for the rapid and efficient eradication of the outbreak is guaranteed, and that the procedures to follow are well rehearsed. It is essential that these plans are established during 'peace-time' and are reviewed regularly. This paper provides suggestions on how to perform laboratory exercises to test preparedness and describes the experiences of two national reference laboratories for CSF. The major lesson learnt was the importance of a well-documented laboratory contingency plan. The major pitfalls encountered were shortage of space, difficulties in guaranteeing biosecurity and sufficient supplies of sterile equipment and consumables. The need for a standardised laboratory information management system, that is used by all those involved in order to reduce the administrative load, is also discussed.

  13. Differentiation of strains of yellow fever virus in γ-irradiated mice

    International Nuclear Information System (INIS)

    Fitzgeorge, R.; Bradish, C.J.

    1980-01-01

    The mouse sensitized by optimal, sub-lethal γ-irradiation has been used for the differentiation of strains of yellow fever virus and for the resolution of their immunogenicity and pathogenicity as distinct characteristics. For different strains of yellow fever virus, the patterns of antibody-synthesis, regulatory immunity (pre-challenge) and protective immunity (post-challenge) are differentially sensitive to γ-irradiation. These critical differentiations of strains of yellow fever virus in γ-irradiated mice have been compared with those shown in normal athymic and immature mice in order to elucidate the range of quantifiable in vivo characteristics and the course of the virus-host interaction. This is discussed as a basis for the comparisons of the responses of model and principal hosts to vaccines and pathogens. (author)

  14. Susceptibility of swine to H5 and H7 low pathogenic avian influenza viruses.

    Science.gov (United States)

    Balzli, Charles; Lager, Kelly; Vincent, Amy; Gauger, Phillip; Brockmeier, Susan; Miller, Laura; Richt, Juergen A; Ma, Wenjun; Suarez, David; Swayne, David E

    2016-07-01

    The ability of pigs to become infected with low pathogenic avian influenza (LPAI) viruses and then generate mammalian adaptable influenza A viruses is difficult to determine. Yet, it is an important link to understanding any relationship between LPAI virus ecology and possible epidemics among swine and/or humans. Assess susceptibility of pigs to LPAI viruses found within the United States and their direct contact transmission potential. Pigs were inoculated with one of ten H5 or H7 LPAI viruses selected from seven different bird species to test infectivity, virulence, pathogenesis, and potential to transmit virus to contact pigs through histological, RRT-PCR and seroconversion data. Although pigs were susceptible to infection with each of the LPAI viruses, no clinical disease was recognized in any pig. During the acute phase of the infection, minor pulmonary lesions were found in some pigs and one or more pigs in each group were RRT-PCR-positive in the lower respiratory tract, but no virus was detected in upper respiratory tract (negative nasal swabs). Except for one group, one or more pigs in each LPAI group developed antibody. No LPAI viruses transmitted to contact pigs. LPAI strains from various bird populations within the United States are capable of infecting pigs. Although adaptability and transmission of individual strains seem unlikely, the subclinical nature of the infections demonstrates the need to improve sampling and testing methods to more accurately measure incidence of LPAI virus infection in pigs, and their potential role in human-zoonotic LPAI virus dynamics. © 2016 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

  15. Antigenically Diverse Swine Origin H1N1 Variant Influenza Viruses Exhibit Differential Ferret Pathogenesis and Transmission Phenotypes.

    Science.gov (United States)

    Pulit-Penaloza, Joanna A; Jones, Joyce; Sun, Xiangjie; Jang, Yunho; Thor, Sharmi; Belser, Jessica A; Zanders, Natosha; Creager, Hannah M; Ridenour, Callie; Wang, Li; Stark, Thomas J; Garten, Rebecca; Chen, Li-Mei; Barnes, John; Tumpey, Terrence M; Wentworth, David E; Maines, Taronna R; Davis, C Todd

    2018-06-01

    Influenza A(H1) viruses circulating in swine represent an emerging virus threat, as zoonotic infections occur sporadically following exposure to swine. A fatal infection caused by an H1N1 variant (H1N1v) virus was detected in a patient with reported exposure to swine and who presented with pneumonia, respiratory failure, and cardiac arrest. To understand the genetic and phenotypic characteristics of the virus, genome sequence analysis, antigenic characterization, and ferret pathogenesis and transmissibility experiments were performed. Antigenic analysis of the virus isolated from the fatal case, A/Ohio/09/2015, demonstrated significant antigenic drift away from the classical swine H1N1 variant viruses and H1N1 pandemic 2009 viruses. A substitution in the H1 hemagglutinin (G155E) was identified that likely impacted antigenicity, and reverse genetics was employed to understand the molecular mechanism of antibody escape. Reversion of the substitution to 155G, in a reverse genetics A/Ohio/09/2015 virus, showed that this residue was central to the loss of hemagglutination inhibition by ferret antisera raised against a prototypical H1N1 pandemic 2009 virus (A/California/07/2009), as well as gamma lineage classical swine H1N1 viruses, demonstrating the importance of this residue for antibody recognition of this H1 lineage. When analyzed in the ferret model, A/Ohio/09/2015 and another H1N1v virus, A/Iowa/39/2015, as well as A/California/07/2009, replicated efficiently in the respiratory tract of ferrets. The two H1N1v viruses transmitted efficiently among cohoused ferrets, but respiratory droplet transmission studies showed that A/California/07/2009 transmitted through the air more efficiently. Preexisting immunity to A/California/07/2009 did not fully protect ferrets from challenge with A/Ohio/09/2015. IMPORTANCE Human infections with classical swine influenza A(H1N1) viruses that circulate in pigs continue to occur in the United States following exposure to swine. To

  16. Fever

    Science.gov (United States)

    ... also cause fevers. Some examples are: Arthritis or connective tissue illnesses such as rheumatoid arthritis and systemic lupus erythematosus Ulcerative colitis and Crohn disease Vasculitis or periarteritis nodosa The first symptom of a cancer may be a fever. This is particularly true ...

  17. Oronasal and intramuscular vaccination of swine with a modified live porcine parvovirus vaccine: multiplication and transmission of the vaccine virus.

    Science.gov (United States)

    Paul, P S; Mengeling, W L

    1984-12-01

    An attenuated strain NADL-2 of porcine parvovirus (PPV) has been used at the 54th cell culture passage as a modified live-virus (MLV) vaccine. The present study was conducted to determine the minimum immunizing dose of MLV, the extent of MLV multiplication in swine tissues, and its transmission from swine administered MLV oronasally or intramuscularly. Immune response to MLV was dose dependent and swine responded to as little as 10(2) median cell-culture infective doses (CCID50). A 10(5) CCID50 of MLV, the largest dose given, induced the best immune response and was used in subsequent experiments. Route of MLV administration also was found to be important. The MLV replicated in tissues of swine after IM inoculation; however, viral antigen in tissues was less, as measured by immunofluorescence, and serum hemagglutination-inhibition titers for PPV were lower in MLV-inoculated swine than we have previously observed in virulent PPV-inoculated swine. In contrast, oronasal inoculation with MLV did not consistently result in infection of pigs; only 5 of 23 swine had virologic and/or serologic evidence of infection. Virus transmission studies indicated that MLV is shed in feces, but shedding occurs later than that in virulent-PPV-inoculated swine and is inconsistent. Delayed transmission of MLV was observed in contact pigs, which were seronegative at 2 weeks, but became seropositive at 4 weeks--indicating that perhaps a virus population capable of infecting pigs by oronasal route was selected by passage through the pig.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. Characterization of an artificial swine-origin influenza virus with the same gene combination as H1N1/2009 virus: a genesis clue of pandemic strain.

    Science.gov (United States)

    Zhao, Xueli; Sun, Yipeng; Pu, Juan; Fan, Lihong; Shi, Weimin; Hu, Yanxin; Yang, Jun; Xu, Qi; Wang, Jingjing; Hou, Dongjun; Ma, Guangpeng; Liu, Jinhua

    2011-01-01

    Pandemic H1N1/2009 influenza virus, derived from a reassortment of avian, human, and swine influenza viruses, possesses a unique gene segment combination that had not been detected previously in animal and human populations. Whether such a gene combination could result in the pathogenicity and transmission as H1N1/2009 virus remains unclear. In the present study, we used reverse genetics to construct a reassortant virus (rH1N1) with the same gene combination as H1N1/2009 virus (NA and M genes from a Eurasian avian-like H1N1 swine virus and another six genes from a North American triple-reassortant H1N2 swine virus). Characterization of rH1N1 in mice showed that this virus had higher replicability and pathogenicity than those of the seasonal human H1N1 and Eurasian avian-like swine H1N1 viruses, but was similar to the H1N1/2009 and triple-reassortant H1N2 viruses. Experiments performed on guinea pigs showed that rH1N1 was not transmissible, whereas pandemic H1N1/2009 displayed efficient transmissibility. To further determine which gene segment played a key role in transmissibility, we constructed a series of reassortants derived from rH1N1 and H1N1/2009 viruses. Direct contact transmission studies demonstrated that the HA and NS genes contributed to the transmission of H1N1/2009 virus. Second, the HA gene of H1N1/2009 virus, when combined with the H1N1/2009 NA gene, conferred efficient contact transmission among guinea pigs. The present results reveal that not only gene segment reassortment but also amino acid mutation were needed for the generation of the pandemic influenza virus.

  19. Characterization of an artificial swine-origin influenza virus with the same gene combination as H1N1/2009 virus: a genesis clue of pandemic strain.

    Directory of Open Access Journals (Sweden)

    Xueli Zhao

    Full Text Available Pandemic H1N1/2009 influenza virus, derived from a reassortment of avian, human, and swine influenza viruses, possesses a unique gene segment combination that had not been detected previously in animal and human populations. Whether such a gene combination could result in the pathogenicity and transmission as H1N1/2009 virus remains unclear. In the present study, we used reverse genetics to construct a reassortant virus (rH1N1 with the same gene combination as H1N1/2009 virus (NA and M genes from a Eurasian avian-like H1N1 swine virus and another six genes from a North American triple-reassortant H1N2 swine virus. Characterization of rH1N1 in mice showed that this virus had higher replicability and pathogenicity than those of the seasonal human H1N1 and Eurasian avian-like swine H1N1 viruses, but was similar to the H1N1/2009 and triple-reassortant H1N2 viruses. Experiments performed on guinea pigs showed that rH1N1 was not transmissible, whereas pandemic H1N1/2009 displayed efficient transmissibility. To further determine which gene segment played a key role in transmissibility, we constructed a series of reassortants derived from rH1N1 and H1N1/2009 viruses. Direct contact transmission studies demonstrated that the HA and NS genes contributed to the transmission of H1N1/2009 virus. Second, the HA gene of H1N1/2009 virus, when combined with the H1N1/2009 NA gene, conferred efficient contact transmission among guinea pigs. The present results reveal that not only gene segment reassortment but also amino acid mutation were needed for the generation of the pandemic influenza virus.

  20. Fever

    Directory of Open Access Journals (Sweden)

    Tamas Bartfai

    2010-01-01

    Full Text Available Measurement of body temperature remains one of the most common ways to assess health. An increase in temperature above what is considered to be a normal value is inevitably regarded as a sure sign of disease and referred to with one simple word: fever. In this review, we summarize how research on fever allowed the identification of the exogenous and endogenous molecules and pathways mediating the fever response. We also show how temperature elevation is common to different pathologies and how the molecular components of the fever-generation pathway represent drug targets for antipyretics, such as acetylsalicylic acid, the first “blockbuster drug”. We also show how fever research provided new insights into temperature and energy homeostasis, and into treatment of infection and inflammation.

  1. Marburg hemorrhagic fever associated with multiple genetic lineages of virus

    DEFF Research Database (Denmark)

    Bausch, D G; Nichol, S T; Muyembe-Tamfum, J J

    2006-01-01

    Background An outbreak of Marburg hemorrhagic fever was first observed in a gold-mining village in northeastern Democratic Republic of the Congo in October 1998. Methods We investigated the outbreak of Marburg hemorrhagic fever most intensively in May and October 1999. Sporadic cases and short ch...

  2. Single-particle cryo-electron microscopy of Rift Valley fever virus

    OpenAIRE

    Sherman, Michael B.; Freiberg, Alexander N.; Holbrook, Michael R.; Watowich, Stanley J.

    2009-01-01

    Rift Valley fever virus (RVFV; Bunyaviridae; Phlebovirus) is an emerging human veterinary pathogen causing acute hepatitis in ruminants and has the potential to Single-particle cryo-EM reconstruction of RVFV MP-12 hemorrhagic fever in humans. We report a three-dimensional reconstruction of RVFV vaccine strain MP-12 (RVFV MP-12) by cryo-electron microcopy using icosahedral symmetry of individual virions. Although the genomic core of RVFV MP-12 is apparently poorly ordered, the glycoproteins on...

  3. Reassortant H1N1 influenza virus vaccines protect pigs against pandemic H1N1 influenza virus and H1N2 swine influenza virus challenge.

    Science.gov (United States)

    Yang, Huanliang; Chen, Yan; Shi, Jianzhong; Guo, Jing; Xin, Xiaoguang; Zhang, Jian; Wang, Dayan; Shu, Yuelong; Qiao, Chuanling; Chen, Hualan

    2011-09-28

    Influenza A (H1N1) virus has caused human influenza outbreaks in a worldwide pandemic since April 2009. Pigs have been found to be susceptible to this influenza virus under experimental and natural conditions, raising concern about their potential role in the pandemic spread of the virus. In this study, we generated a high-growth reassortant virus (SC/PR8) that contains the hemagglutinin (HA) and neuraminidase (NA) genes from a novel H1N1 isolate, A/Sichuan/1/2009 (SC/09), and six internal genes from A/Puerto Rico/8/34 (PR8) virus, by genetic reassortment. The immunogenicity and protective efficacy of this reassortant virus were evaluated at different doses in a challenge model using a homologous SC/09 or heterologous A/Swine/Guangdong/1/06(H1N2) virus (GD/06). Two doses of SC/PR8 virus vaccine elicited high-titer serum hemagglutination inhibiting (HI) antibodies specific for the 2009 H1N1 virus and conferred complete protection against challenge with either SC/09 or GD/06 virus, with reduced lung lesions and viral shedding in vaccine-inoculated animals compared with non-vaccinated control animals. These results indicated for the first time that a high-growth SC/PR8 reassortant H1N1 virus exhibits properties that are desirable to be a promising vaccine candidate for use in swine in the event of a pandemic H1N1 influenza. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Identification of swine H1N2/pandemic H1N1 reassortant influenza virus in pigs, United States.

    Science.gov (United States)

    Ali, Ahmed; Khatri, Mahesh; Wang, Leyi; Saif, Yehia M; Lee, Chang-Won

    2012-07-06

    In October and November 2010, novel H1N2 reassortant influenza viruses were identified from pigs showing mild respiratory signs that included cough and depression. Sequence and phylogenetic analysis showed that the novel H1N2 reassortants possesses HA and NA genes derived from recent H1N2 swine isolates similar to those isolated from Midwest. Compared to the majority of reported reassortants, both viruses preserved human-like host restrictive and putative antigenic sites in their HA and NA genes. The four internal genes, PB2, PB1, PA, and NS were similar to the contemporary swine triple reassortant viruses' internal genes (TRIG). Interestingly, NP and M genes of the novel reassortants were derived from the 2009 pandemic H1N1. The NP and M proteins of the two isolates demonstrated one (E16G) and four (G34A, D53E, I109T, and V313I) amino acid changes in the M2 and NP proteins, respectively. Similar amino acid changes were also noticed upon incorporation of the 2009 pandemic H1N1 NP in other reassortant viruses reported in the U.S. Thus the role of those amino acids in relation to host adaptation need to be further investigated. The reassortments of pandemic H1N1 with swine influenza viruses and the potential of interspecies transmission of these reassortants from swine to other species including human indicate the importance of systematic surveillance of swine population to determine the origin, the prevalence of similar reassortants in the U.S. and their impact on both swine production and public health. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Detection of yellow fever virus genomes from four imported cases in China.

    Science.gov (United States)

    Cui, Shujuan; Pan, Yang; Lyu, Yanning; Liang, Zhichao; Li, Jie; Sun, Yulan; Dou, Xiangfeng; Tian, Lili; Huo, Da; Chen, Lijuan; Li, Xinyu; Wang, Quanyi

    2017-07-01

    Yellow fever virus (YFV), as the first proven human-pathogenic virus, is still a major public health problem with a dramatic upsurge in recent years. This is a report on four imported cases of yellow fever virus into China identified by whole genome sequencing. Phylogenetic analysis was performed and the results showed that these four viruses were highly homologous with Angola 71 strains (AY968064). In addition, effective mutations of amino acids were not observed in the E protein domain of four viruses, thus confirming the effectiveness of the YFV-17D vaccine (X03700). Although there is low risk of local transmission in most part of China, the increasing public health risk of YF caused by international exchange should not be ignored. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  6. Novel reassortant influenza A(H1N2) virus derived from A(H1N1)pdm09 virus isolated from swine, Japan, 2012.

    Science.gov (United States)

    Kobayashi, Miho; Takayama, Ikuyo; Kageyama, Tsutomu; Tsukagoshi, Hiroyuki; Saitoh, Mika; Ishioka, Taisei; Yokota, Yoko; Kimura, Hirokazu; Tashiro, Masato; Kozawa, Kunihisa

    2013-12-01

    We isolated a novel influenza virus A(H1N2) strain from a pig on January 13, 2012, in Gunma Prefecture, Japan. Phylogenetic analysis showed that the strain was a novel type of double-reassortant virus derived from the swine influenza virus strains H1N1pdm09 and H1N2, which were prevalent in Gunma at that time.

  7. Comparative pathogenesis of an avian H5N2 and a swine H1N1 influenza virus in pigs.

    Directory of Open Access Journals (Sweden)

    Annebel De Vleeschauwer

    2009-08-01

    Full Text Available Pigs are considered intermediate hosts for the transmission of avian influenza viruses (AIVs to humans but the basic organ pathogenesis of AIVs in pigs has been barely studied. We have used 42 four-week-old influenza naive pigs and two different inoculation routes (intranasal and intratracheal to compare the pathogenesis of a low pathogenic (LP H5N2 AIV with that of an H1N1 swine influenza virus. The respiratory tract and selected extra-respiratory tissues were examined for virus replication by titration, immunofluorescence and RT-PCR throughout the course of infection. Both viruses caused a productive infection of the entire respiratory tract and epithelial cells in the lungs were the major target. Compared to the swine virus, the AIV produced lower virus titers and fewer antigen positive cells at all levels of the respiratory tract. The respiratory part of the nasal mucosa in particular showed only rare AIV positive cells and this was associated with reduced nasal shedding of the avian compared to the swine virus. The titers and distribution of the AIV varied extremely between individual pigs and were strongly affected by the route of inoculation. Gross lung lesions and clinical signs were milder with the avian than with the swine virus, corresponding with lower viral loads in the lungs. The brainstem was the single extra-respiratory tissue found positive for virus and viral RNA with both viruses. Our data do not reject the theory of the pig as an intermediate host for AIVs, but they suggest that AIVs need to undergo genetic changes to establish full replication potential in pigs. From a biomedical perspective, experimental LP H5 AIV infection of pigs may be useful to examine heterologous protection provided by H5 vaccines or other immunization strategies, as well as for further studies on the molecular pathogenesis and neurotropism of AIVs in mammals.

  8. Hiding the evidence: two strategies for innate immune evasion by hemorrhagic fever viruses.

    Science.gov (United States)

    Hastie, Kathryn M; Bale, Shridhar; Kimberlin, Christopher R; Saphire, Erica Ollmann

    2012-04-01

    The innate immune system is one of the first lines of defense against invading pathogens. Pathogens have, in turn, evolved different strategies to counteract these responses. Recent studies have illuminated how the hemorrhagic fever viruses Ebola and Lassa fever prevent host sensing of double-stranded RNA (dsRNA), a key hallmark of viral infection. The ebolavirus protein VP35 adopts a unique bimodal configuration to mask key cellular recognition sites on dsRNA. Conversely, the Lassa fever virus nucleoprotein actually digests the dsRNA signature. Collectively, these structural and functional studies shed new light on the mechanisms of pathogenesis of these viruses and provide new targets for therapeutic intervention. Copyright © 2012. Published by Elsevier B.V.

  9. Genetic analysis of human and swine influenza A viruses isolated in Northern Italy during 2010-2015.

    Science.gov (United States)

    Chiapponi, C; Ebranati, E; Pariani, E; Faccini, S; Luppi, A; Baioni, L; Manfredi, R; Carta, V; Merenda, M; Affanni, P; Colucci, M E; Veronesi, L; Zehender, G; Foni, E

    2018-02-01

    Influenza A virus (IAV) infection in swine plays an important role in the ecology of influenza viruses. The emergence of new IAVs comes through different mechanisms, with the genetic reassortment of genes between influenza viruses, also originating from different species, being common. We performed a genetic analysis on 179 IAV isolates from humans (n. 75) and pigs (n. 104) collected in Northern Italy between 2010 and 2015, to monitor the genetic exchange between human and swine IAVs. No cases of human infection with swine strains were noticed, but direct infections of swine with H1N1pdm09 strains were detected. Moreover, we pointed out a continuous circulation of H1N1pdm09 strains in swine populations evidenced by the introduction of internal genes of this subtype. These events contribute to generating new viral variants-possibly endowed with pandemic potential-and emphasize the importance of continuous surveillance at both animal and human level. © 2017 The Authors. Zoonoses and Public Health published by Blackwell Verlag GmbH.

  10. Assessment of the risk of African swine fever introduction into Finland using NORA-a rapid tool for semiquantitative assessment of the risk.

    Science.gov (United States)

    Kyyrö, J; Sahlström, L; Lyytikäinen, T

    2017-12-01

    The NORA rapid risk assessment tool was developed for situations where there is a change in the disease status of easily transmissible animal diseases in neighbouring countries or in countries with significant interactions with Finland. The goal was to develop a tool that is quick to use and will provide consistent results to support risk management decisions. The model contains 63 questions that define the potential for entry and exposure by nine different pathways. The magnitude of the consequences is defined by 23 statements. The weight of different pathways is defined according to the properties of the assessed disease. The model was built as an Excel spreadsheet and is intended for use by animal health control administrators. As an outcome, the model gives the possible pathways of disease entry into the country, an overall approximation for the probability of entry and the subsequent exposure, an overall estimate for the consequences and a combined overall risk estimate (probability multiplied by magnitude of consequences). Model validity was assessed by expert panels. Outside Africa, African swine fever is currently established in Russia and Sardinia. In addition, there have been cases in both wild boar and domestic pigs in Latvia, Lithuania, Poland and Estonia. Finland has frequent contacts with Russia and Estonia, especially through passengers. The risk of African swine fever (ASF) introduction into Finland was tested with NORA for the situation in December 2015, when ASF was endemic in many parts of Russia, Africa and Sardinia and was present in Baltic countries and in Poland. African swine fever was assessed to have a high probability of entry into Finland, with high consequences and therefore a high overall risk. © 2017 Blackwell Verlag GmbH.

  11. An approach to model monitoring and surveillance data of wildlife diseases-exemplified by Classical Swine Fever in wild boar.

    Science.gov (United States)

    Stahnke, N; Liebscher, V; Staubach, C; Ziller, M

    2013-11-01

    The analysis of epidemiological field data from monitoring and surveillance systems (MOSSs) in wild animals is of great importance in order to evaluate the performance of such systems. By parameter estimation from MOSS data, conclusions about disease dynamics in the observed population can be drawn. To strengthen the analysis, the implementation of a maximum likelihood estimation is the main aim of our work. The new approach presented here is based on an underlying simple SIR (susceptible-infected-recovered) model for a disease scenario in a wildlife population. The three corresponding classes are assumed to govern the intensities (number of animals in the classes) of non-homogeneous Poisson processes. A sampling rate was defined which describes the process of data collection (for MOSSs). Further, the performance of the diagnostics was implemented in the model by a diagnostic matrix containing misclassification rates. Both descriptions of these MOSS parts were included in the Poisson process approach. For simulation studies, the combined model demonstrates its ability to validly estimate epidemiological parameters, such as the basic reproduction rate R0. These parameters will help the evaluation of existing disease control systems. They will also enable comparison with other simulation models. The model has been tested with data from a Classical Swine Fever (CSF) outbreak in wild boars (Sus scrofa scrofa L.) from a region of Germany (1999-2002). The results show that the hunting strategy as a sole control tool is insufficient to decrease the threshold for susceptible animals to eradicate the disease, since the estimated R0 confirms an ongoing epidemic of CSF. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. African Swine Fever in Uganda: Qualitative Evaluation of Three Surveillance Methods with Implications for Other Resource-Poor Settings.

    Science.gov (United States)

    Chenais, Erika; Sternberg-Lewerin, Susanna; Boqvist, Sofia; Emanuelson, Ulf; Aliro, Tonny; Tejler, Emma; Cocca, Giampaolo; Masembe, Charles; Ståhl, Karl

    2015-01-01

    Animal diseases impact negatively on households and on national economies. In low-income countries, this pertains especially to socio-economic effects on household level. To control animal diseases and mitigate their impact, it is necessary to understand the epidemiology of the disease in its local context. Such understanding, gained through disease surveillance, is often lacking in resource-poor settings. Alternative surveillance methods have been developed to overcome some of the hurdles obstructing surveillance. The objective of this study was to evaluate and qualitatively compare three methods for surveillance of acute infectious diseases using African swine fever in northern Uganda as an example. Report-driven outbreak investigations, participatory rural appraisals (PRAs), and a household survey using a smartphone application were evaluated. All three methods had good disease-detecting capacity, and each of them detected many more outbreaks compared to those reported to the World Organization for Animal Health during the same time period. Apparent mortality rates were similar for the three methods although highest for the report-driven outbreak investigations, followed by the PRAs, and then the household survey. The three methods have different characteristics and the method of choice will depend on the surveillance objective. The optimal situation might be achieved by a combination of the methods: outbreak detection via smartphone-based real-time surveillance, outbreak investigation for collection of biological samples, and a PRA for a better understanding of the epidemiology of the specific outbreak. All three methods require initial investments and continuous efforts. The sustainability of the surveillance system should, therefore, be carefully evaluated before making such investments.

  13. African swine fever in Uganda: qualitative evaluation of three surveillance methods with implications for other resource-poor settings

    Directory of Open Access Journals (Sweden)

    Erika eChenais

    2015-10-01

    Full Text Available Animal diseases impact negatively on households and on national economies. In low-income countries this pertains especially to socio-economic effects on household level. To control animal diseases and mitigate their impact, it is necessary to understand the epidemiology of the disease in its local context. Such understanding, gained through disease surveillance, is often lacking in resource-poor settings. Alternative surveillance methods have been developed to overcome some of the hurdles obstructing surveillance. The objective of this study was to evaluate and qualitatively compare three methods for surveillance of acute infectious diseases using African swine fever (ASF in northern Uganda as an example. Report-driven outbreak investigations, participatory rural appraisals (PRA, and a household survey using a smartphone application were evaluated. All three methods had good disease-detecting capacity, each of them detected many more outbreaks compared to those reported to the World Organization for Animal Health (OIE during the same time period. Apparent mortality rates were similar for the three methods although highest for the report-driven outbreak investigations, followed by the PRAs, and then the household survey. The three methods have different characteristics and the method of choice will depend on the surveillance objective. The optimal situation might be achieved by a combination of the methods: outbreak detection via smartphone-based real-time surveillance, outbreak investigation for collection of biological samples, and a PRA for a better understanding of the epidemiology of the specific outbreak. All three methods require initial investments and continuous efforts. The sustainability of the surveillance system should therefore be carefully evaluated before making such investments.

  14. A novel monoclonal antibody effective against lethal challenge with swine-lineage and 2009 pandemic H1N1 influenza viruses in mice

    Science.gov (United States)

    The HA protein of the 2009 pandemic H1N1viruses (14 H1N1pdm) is antigenically closely related to the HA of classical North American swine H1N1 influenza viruses (cH1N1). Since 1998, through reassortment and incorporation of HA genes from human H3N2 and H1N1 influenza viruses, swine influenza strains...

  15. Assessment of confidence in freedom from Aujeszky's disease and classical swine fever in Danish pigs based on serological sampling—Effect of reducing the number of samples

    DEFF Research Database (Denmark)

    Boklund, Anette; Dahl, J.; Alban, L.

    2013-01-01

    Confirming freedom from disease is important for export of animals and animal products. In Denmark, an intensive surveillance program is in place for Aujeszky's disease (AD) and classical swine fever (CSF), including 34,974 blood samples tested for AD and 37,414 samples tested for CSF (2008 figures...... the posterior probability of freedom (PostPFree) from AD and CSF by use of a scenario tree model. Conventional herds and sows or boars were defined as risk factors (compared to SPF1 herds and finisher pigs), with a relative risk of 2 and 5, respectively. The probability of introduction was modeled...

  16. Genetic characterization of H1N2 swine influenza virus isolated in China and its pathogenesis and inflammatory responses in mice.

    Science.gov (United States)

    Zhang, Yan; Wang, Nan; Cao, Jiyue; Chen, Huanchun; Jin, Meilin; Zhou, Hongbo

    2013-09-01

    In 2009, two H1N2 influenza viruses were isolated from trachea swabs of pigs in Hubei in China. We compared these sequences with the other 18 complete genome sequences of swine H1N2 isolates from China during 2004 to 2010 and undertook extensive analysis of their evolutionary patterns. Six different genotypes - two reassortants between triple reassortant (TR) H3N2 and classical swine (CS) H1N1 virus, three reassortants between TR H1N2, Eurasian avian-like H1N1 swine virus and H9N2 swine virus, and one reassortant between H1N1, H3N2 human virus and CS H1N1 virus - were observed in these 20 swine H1N2 isolates. The TR H1N2 swine virus is the predominant genotype, and the two Hubei H1N2 isolates were located in this cluster. We also used a mouse model to examine the pathogenesis and inflammatory responses of the two isolates. The isolates replicated efficiently in the lung, and exhibited a strong inflammatory response, serious pathological changes and mortality in infected mice. Given the role that swine can play as putative "genetic mixing vessels" and the observed transmission of TR H1N2 in ferrets, H1N2 influenza surveillance in pigs should be increased to minimize the potential threat to public health.

  17. From where did the 2009 'swine-origin' influenza A virus (H1N1 emerge?

    Directory of Open Access Journals (Sweden)

    Armstrong John S

    2009-11-01

    Full Text Available Abstract The swine-origin influenza A (H1N1 virus that appeared in 2009 and was first found in human beings in Mexico, is a reassortant with at least three parents. Six of the genes are closest in sequence to those of H1N2 'triple-reassortant' influenza viruses isolated from pigs in North America around 1999-2000. Its other two genes are from different Eurasian 'avian-like' viruses of pigs; the NA gene is closest to H1N1 viruses isolated in Europe in 1991-1993, and the MP gene is closest to H3N2 viruses isolated in Asia in 1999-2000. The sequences of these genes do not directly reveal the immediate source of the virus as the closest were from isolates collected more than a decade before the human pandemic started. The three parents of the virus may have been assembled in one place by natural means, such as by migrating birds, however the consistent link with pig viruses suggests that human activity was involved. We discuss a published suggestion that unsampled pig herds, the intercontinental live pig trade, together with porous quarantine barriers, generated the reassortant. We contrast that suggestion with the possibility that laboratory errors involving the sharing of virus isolates and cultured cells, or perhaps vaccine production, may have been involved. Gene sequences from isolates that bridge the time and phylogenetic gap between the new virus and its parents will distinguish between these possibilities, and we suggest where they should be sought. It is important that the source of the new virus be found if we wish to avoid future pandemics rather than just trying to minimize the consequences after they have emerged. Influenza virus is a very significant zoonotic pathogen. Public confidence in influenza research, and the agribusinesses that are based on influenza's many hosts, has been eroded by several recent events involving the virus. Measures that might restore confidence include establishing a unified international administrative

  18. Yellow fever virus: genetic and phenotypic diversity and implications for detection, prevention and therapy.

    Science.gov (United States)

    Beasley, David W C; McAuley, Alexander J; Bente, Dennis A

    2015-03-01

    Yellow fever virus (YFV) is the prototypical hemorrhagic fever virus, yet our understanding of its phenotypic diversity and any molecular basis for observed differences in disease severity and epidemiology is lacking, when compared to other arthropod-borne and haemorrhagic fever viruses. This is, in part, due to the availability of safe and effective vaccines resulting in basic YFV research taking a back seat to those viruses for which no effective vaccine occurs. However, regular outbreaks occur in endemic areas, and the spread of the virus to new, previously unaffected, areas is possible. Analysis of isolates from endemic areas reveals a strong geographic association for major genotypes, and recent epidemics have demonstrated the emergence of novel sequence variants. This review aims to outline the current understanding of YFV genetic and phenotypic diversity and its sources, as well as the available animal models for characterizing these differences in vivo. The consequences of genetic diversity for detection and diagnosis of yellow fever and development of new vaccines and therapeutics are discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. HoBi-like viruses: an emerging group of pestiviruses

    Science.gov (United States)

    The genus Pestivirus is composed by four important pathogens of livestock: bovine viral diarrhea virus types 1 and 2 (BVDV-1 and BVDV-2), classical swine fever virus (CSFV) and border disease virus of sheep (BDV). BVDV are major pathogens of cattle and infection results in significant economic losse...

  20. HEMORRHAGIC-FEVER VIRUS-INFECTIONS IN AN ISOLATED RAIN-FOREST AREA OF CENTRAL LIBERIA - LIMITATIONS OF THE INDIRECT IMMUNOFLUORESCENCE SLIDE TEST FOR ANTIBODY SCREENING IN AFRICA

    NARCIS (Netherlands)

    van der Waals, F. W.; Pomeroy, K. L.; Goudsmit, J.; Asher, D. M.; Gajdusek, D. C.

    1986-01-01

    Serum samples from 119 healthy individuals and 106 epilepsy patients inhabiting Grand Bassa County, Liberia, were tested for antibodies to hemorrhagic fever viruses (HFV) by indirect immunofluorescence. E6 Vero cells infected with Lassa fever virus (LAS), Rift Valley Fever virus (RVF), Congo

  1. Pathogenesis of swine influenza virus (Thai isolates in weanling pigs: an experimental trial

    Directory of Open Access Journals (Sweden)

    Kitikoon Pravina

    2009-03-01

    Full Text Available Abstract Background The objective of this study is to investigate the pathogenesis of swine influenza virus (SIV subtype H1N1 and H3N2 (Thai isolates in 22-day-old SPF pigs. Results The study found that all pigs in the infected groups developed typical signs of flu-like symptoms on 1–4 days post- infection (dpi. The H1N1-infected pigs had greater lung lesion scores than those of the H3N2-infected pigs. Histopathological lesions related to swine influenza-induced lesions consisting of epithelial cells damage, airway plugging and peribronchial and perivascular mononuclear cell infiltration were present in both infected groups. Immunofluorescence and immunohistochemistry using nucleoprotein specific monoclonal antibodies revealed positive staining cells in lung sections of both infected groups at 2 and 4 dpi. Virus shedding was detected at 2 dpi from both infected groups as demonstrated by RT-PCR and virus isolation. Conclusion The results demonstrated that both SIV subtypes were able to induce flu-like symptoms and lung lesions in weanling pigs. However the severity of the diseases with regards to lung lesions both gross and microscopic lesions was greater in the H1N1-infected pigs. Based on phylogenetic analysis, haemagglutinin gene of subtype H1N1 from Thailand clustered with the classical H1 SIV sequences and neuraminidase gene clustered with virus of avian origin, whereas, both genes of H3N2 subtype clustered with H3N2 human-like SIV from the 1970s.

  2. The molecular determinants of antibody recognition and antigenic drift in the H3 hemagglutinin of swine influenza A virus

    Science.gov (United States)

    Influenza A virus (IAV) of the H3 subtype is an important pathogen that affects both humans and swine. The main intervention strategy for preventing infection is vaccination to induce neutralizing antibodies against the surface glycoprotein hemagglutinin (HA). However, due to antigenic drift, vaccin...

  3. Two years of surveillance of influenza a virus infection in a swine herd. Results of virological, serological and pathological studies.

    Science.gov (United States)

    Cappuccio, Javier; Dibarbora, Marina; Lozada, Inés; Quiroga, Alejandra; Olivera, Valeria; Dángelo, Marta; Pérez, Estefanía; Barrales, Hernán; Perfumo, Carlos; Pereda, Ariel; Pérez, Daniel R

    2017-02-01

    Swine farms provide a dynamic environment for the evolution of influenza A viruses (IAVs). The present report shows the results of a surveillance effort of IAV infection in one commercial swine farm in Argentina. Two cross-sectional serological and virological studies (n=480) were carried out in 2011 and 2012. Virus shedding was detected in nasal samples from pigs from ages 7, 21 and 42-days old. More than 90% of sows and gilts but less than 40% of 21-days old piglets had antibodies against IAV. In addition, IAV was detected in 8/17 nasal swabs and 10/15 lung samples taken from necropsied pigs. A subset of these samples was further processed for virus isolation resulting in 6 viruses of the H1N2 subtype (δ2 cluster). Pathological studies revealed an association between suppurative bronchopneumonia and necrotizing bronchiolitis with IAV positive samples. Statistical analyses showed that the degree of lesions in bronchi, bronchiole, and alveoli was higher in lungs positive to IAV. The results of this study depict the relevance of continuing long-term active surveillance of IAV in swine populations to establish IAV evolution relevant to swine and humans. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. CDC Recommendations to Reduce the Risk of H3N2v Flu Virus Infection for Fairgoers and Swine Exhibitors

    Centers for Disease Control (CDC) Podcasts

    2012-09-10

    In this podcast, Dr. Lyn Finelli discusses CDC’s recommendations for reducing the risk of infection with H3N2v flu viruses for fairgoers and swine exhibitors.  Created: 9/10/2012 by National Center for Immunization and Respiratory Diseases (NCIRD).   Date Released: 9/10/2012.

  5. Experimental transmission of West Nile Virus and Rift Valley Fever Virus by Culex pipiens from Lebanon.

    Directory of Open Access Journals (Sweden)

    Renée Zakhia

    2018-01-01

    Full Text Available West Nile virus (WNV and Rift Valley fever virus (RVFV are two emerging arboviruses transmitted by Culex pipiens species that includes two biotypes: pipiens and molestus. In Lebanon, human cases caused by WNV and RVFV have never been reported. However, the introduction of these viruses in the country is likely to occur through the migratory birds and animal trades. In this study, we evaluated the ability of Cx. pipiens, a predominant mosquito species in urban and rural regions in Lebanon, to transmit WNV and RVFV. Culex egg rafts were collected in the West Bekaa district, east of Lebanon and adult females of Cx. pipiens were experimentally infected with WNV and RVFV Clone 13 strain at titers of 1.6×108 and 1.33×107 plaque forming units (PFU/mL, respectively. We estimated viral infection, dissemination and transmission at 3, 7, 14 and 19 days post infection (dpi. Results showed that infection was higher for WNV than for RVFV from 3 dpi to 19 dpi. Viral dissemination and transmission started from 3 dpi for WNV; and only from 19 dpi for RVFV. Moreover, Cx. pipiens were able to excrete in saliva a higher number of viral particles of WNV (1028 ± 405 PFU/saliva at 19 dpi than RVFV (42 PFU/saliva at 19 dpi. Cx. pipiens from Lebanon are efficient experimental vectors of WNV and to a lower extent, RVFV. These findings should stimulate local authorities to establish an active entomological surveillance in addition to animal surveys for both viruses in the country.

  6. Zika Virus, a Cause of Fever in Central Java, Indonesia

    Science.gov (United States)

    1981-01-01

    considered with the isolation of ZIKA Lee, V. H. & Moore, D. L. (1972). Vectors of the virus from a variety of other Aedes of the subgenus 1969 yellow...a vector of the virus . 46, 669-673. Marchette, N. J., Garcia, R. & Rudnick, A. (1969). Acknowledgements Isolation of Zika virus from Aedes aegypti mos...hemagglutination test for the diagnosis of human Twelve isolations of Zika virus from Aedes leptospirosis. Journal of Clinical Microbiology

  7. Characterization of Viral Load, Viability and Persistence of Influenza A Virus in Air and on Surfaces of Swine Production Facilities.

    Directory of Open Access Journals (Sweden)

    Victor Neira

    Full Text Available Indirect transmission of influenza A virus (IAV in swine is poorly understood and information is lacking on levels of environmental exposure encountered by swine and people during outbreaks of IAV in swine barns. We characterized viral load, viability and persistence of IAV in air and on surfaces during outbreaks in swine barns. IAV was detected in pigs, air and surfaces from five confirmed outbreaks with 48% (47/98 of oral fluid, 38% (32/84 of pen railing and 43% (35/82 of indoor air samples testing positive by IAV RT-PCR. IAV was isolated from air and oral fluids yielding a mixture of subtypes (H1N1, H1N2 and H3N2. Detection of IAV RNA from air was sustained during the outbreaks with maximum levels estimated between 7 and 11 days from reported onset. Our results indicate that during outbreaks of IAV in swine, aerosols and surfaces in barns contain significant levels of IAV potentially representing an exposure hazard to both swine and people.

  8. Live Zika virus chimeric vaccine candidate based on a yellow fever 17-D attenuated backbone

    OpenAIRE

    Nougairede, Antoine; Klitting, Raphaelle; Aubry, Fabien; Gilles, Magali; Touret, Franck; De Lamballerie, Xavier

    2018-01-01

    Zika virus (ZIKV) recently dispersed throughout the tropics and sub-tropics causing epidemics associated with congenital disease and neurological complications. There is currently no commercial vaccine for ZIKV. Here we describe the initial development of a chimeric virus containing the prM/E proteins of a ZIKV epidemic strain incorporated into a yellow fever 17-D attenuated backbone. Using the versatile and rapid ISA (Infectious Subgenomic Amplicons) reverse genetics method, we compared diff...

  9. Genetic analysis and antigenic characterization of swine origin influenza viruses isolated from humans in the United States, 1990-2010.

    Science.gov (United States)

    Shu, Bo; Garten, Rebecca; Emery, Shannon; Balish, Amanda; Cooper, Lynn; Sessions, Wendy; Deyde, Varough; Smith, Catherine; Berman, LaShondra; Klimov, Alexander; Lindstrom, Stephen; Xu, Xiyan

    2012-01-05

    Swine influenza viruses (SIV) have been recognized as important pathogens for pigs and occasional human infections with swine origin influenza viruses (SOIV) have been reported. Between 1990 and 2010, a total of twenty seven human cases of SOIV infections have been identified in the United States. Six viruses isolated from 1990 to 1995 were recognized as classical SOIV (cSOIV) A(H1N1). After 1998, twenty-one SOIV recovered from human cases were characterized as triple reassortant (tr_SOIV) inheriting genes from classical swine, avian and human influenza viruses. Of those twenty-one tr_SOIV, thirteen were of A(H1N1), one of A(H1N2), and seven of A(H3N2) subtype. SOIV characterized were antigenically and genetically closely related to the subtypes of influenza viruses circulating in pigs but distinct from contemporary influenza viruses circulating in humans. The diversity of subtypes and genetic lineages in SOIV cases highlights the importance of continued surveillance at the animal-human interface. Copyright © 2011. Published by Elsevier Inc.

  10. Identification of Human H1N2 and Human-Swine Reassortant H1N2 and H1N1 Influenza A Viruses among Pigs in Ontario, Canada (2003 to 2005)†

    OpenAIRE

    Karasin, Alexander I.; Carman, Suzanne; Olsen, Christopher W.

    2006-01-01

    Since 2003, three novel genotypes of H1 influenza viruses have been recovered from Canadian pigs, including a wholly human H1N2 virus and human-swine reassortants. These isolates demonstrate that human-lineage H1N2 viruses are infectious for pigs and that viruses with a human PB1/swine PA/swine PB2 polymerase complex can replicate in pigs.

  11. Risk of African swine fever introduction into the European Union through transport-associated routes: returning trucks and waste from international ships and planes

    Directory of Open Access Journals (Sweden)

    Mur Lina

    2012-08-01

    Full Text Available Abstract Background The uncontrolled presence of African swine fever (ASF in Russian Federation (RF poses a serious risk to the whole European Union (EU pig industry. Although trade of pigs and their products is banned since the official notification in June 2007, the potential introduction of ASF virus (ASFV may occur by other routes, which are very frequent in ASF, and more difficult to control, such as contaminated waste or infected vehicles. This study was intended to estimate the risk of ASFV introduction into the EU through three types of transport routes: returning trucks, waste from international ships and waste from international planes, which will be referred here as transport-associated routes (TAR. Since no detailed and official information was available for these routes, a semi-quantitative model based on the weighted combination of risk factors was developed to estimate the risk of ASFV introduction by TAR. Relative weights for combination of different risk factors as well as validation of the model results were obtained by an expert opinion elicitation. Results Model results indicate that the relative risk for ASFV introduction through TAR in most of the EU countries (16 is low, although some countries, specifically Poland and Lithuania, concentrate high levels of risk, the returning trucks route being the analyzed TAR that currently poses the highest risk for ASFV introduction into the EU. The spatial distribution of the risk of ASFV introduction varies importantly between the analyzed introduction routes. Results also highlight the need to increase the awareness and precautions for ASF prevention, particularly ensuring truck disinfection, to minimize the potential risk of entrance into the EU. Conclusions This study presents the first assessment of ASF introduction into the EU through TAR. The innovative model developed here could be used in data scarce situations for estimating the relative risk associated to each EU country

  12. Qualitative analysis of the risks and practices associated with the spread of African swine fever within the smallholder pig value chains in Uganda.

    Science.gov (United States)

    Dione, Michel; Ouma, Emily; Opio, Felix; Kawuma, Brian; Pezo, Danilo

    2016-12-01

    A study was undertaken between September 2014 and December 2014 to assess the perceptions of smallholder pig value chain actors of the risks and practices associated with the spread of African swine fever (ASF) disease within the pig value chains. Data was collected from 136 value chain actors and 36 key informants through 17 group discussions and two key informant interview (KII) sessions respectively using Participatory Rural Appraisal (PRA) tools. Results from this study revealed that according to value chain actors and stakeholders, the transporting, slaughtering, and collecting/bulking nodes represent the highest risk, followed by the inputs and services (feeds and drugs) supply nodes. The processing, whole sale and consumption nodes represented the lowest risk. Value chain actors are aware of the disease and its consequences to the pig industry, however biosecurity measures are poorly implemented at all nodes. As for the causes, value chain actors pointed to several factors, such as inadequate knowledge of mechanisms for the spread of the disease, poor enforcement of regulations on disease control, and low capacities of actors to implement biosecurity measures, amongst others. Although traders, butchers and veterinary practitioners accepted that they played an important role in the spread of the virus, they did not perceive themselves as key actors in the control of the disease; instead, they believed that only farmers should adopt biosecurity measures on their farms because they keep the pigs for a longer period. Most of the recommendations given by the value chain actors for controlling and preventing ASF disease were short term, and targeted mainly pig producers. These recommendations included: the establishment of live pig collection centres so that traders and brokers do not have to directly access pig farms, capacity building of value chain actors on application of biosecurity, enactment and enforcement of by-laws on live pig movements and establishment

  13. Influenza A (H3N2) virus in swine at agricultural fairs and transmission to humans, Michigan and Ohio, USA, 2016

    Science.gov (United States)

    An 18 case outbreak of variant H3N2 influenza A occurred during 2016 after exposure to influenza-infected swine at seven agricultural fairs. Sixteen cases were infected with a reassortant between 2010-2011 human seasonal H3N2 strains and viruses endemic in North American swine, a viral lineage incre...

  14. Small molecule inhibitors of ER α-glucosidases are active against multiple hemorrhagic fever viruses.

    Science.gov (United States)

    Chang, Jinhong; Warren, Travis K; Zhao, Xuesen; Gill, Tina; Guo, Fang; Wang, Lijuan; Comunale, Mary Ann; Du, Yanming; Alonzi, Dominic S; Yu, Wenquan; Ye, Hong; Liu, Fei; Guo, Ju-Tao; Mehta, Anand; Cuconati, Andrea; Butters, Terry D; Bavari, Sina; Xu, Xiaodong; Block, Timothy M

    2013-06-01

    Host cellular endoplasmic reticulum α-glucosidases I and II are essential for the maturation of viral glycosylated envelope proteins that use the calnexin mediated folding pathway. Inhibition of these glycan processing enzymes leads to the misfolding and degradation of these viral glycoproteins and subsequent reduction in virion secretion. We previously reported that, CM-10-18, an imino sugar α-glucosidase inhibitor, efficiently protected the lethality of dengue virus infection of mice. In the current study, through an extensive structure-activity relationship study, we have identified three CM-10-18 derivatives that demonstrated superior in vitro antiviral activity against representative viruses from four viral families causing hemorrhagic fever. Moreover, the three novel imino sugars significantly reduced the mortality of two of the most pathogenic hemorrhagic fever viruses, Marburg virus and Ebola virus, in mice. Our study thus proves the concept that imino sugars are promising drug candidates for the management of viral hemorrhagic fever caused by variety of viruses. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Serological reactions in Rhesus monkeys inoculated with the 17D strain of yellow fever virus.

    Science.gov (United States)

    GROOT, H

    1962-01-01

    Haemagglutination-inhibition tests, which depend on the appearance of haemagglutination-inhibiting antibodies in the serum in virus infections, are in common use in the study of arthropod-borne diseases. This paper contains the results of an investigation into the appearance and pattern of haemagglutination-inhibiting antibodies in the serum of rhesus monkeys inoculated intracerebrally with the 17D strain of yellow fever virus during the testing of seed lots of yellow fever vaccine. These antibodies appeared on the tenth day after inoculation, and were still demonstrable four years later. In all of the eight monkeys tested complement-fixing and neutralizing antibodies against yellow fever antigens also developed, and in six out of the eight heterologous antigens developed.

  16. Antibodies against Severe Fever with Thrombocytopenia Syndrome Virus in Healthy Persons, China, 2013

    Science.gov (United States)

    Zhang, Lei; Sun, Jimin; Yan, Jie; Lv, Huakun; Chai, Chengliang; Sun, Yi; Shao, Bin; Jiang, Jianmin; Chen, Zhiping

    2014-01-01

    In June 2013, a subclinical infection with severe fever with thrombocytopenia syndrome virus (SFTSV) was detected in Zhejiang Province, China, prompting seroprevalence studies in 6 districts within the province. Of 986 healthy persons tested, 71 had IgG antibodies against SFTSV. This finding suggests that most natural infections with SFTSV are mild or subclinical. PMID:25061813

  17. Effect of environmental temperature on the vector competence of mosquitoes for Rift Valley fever virus

    Science.gov (United States)

    Environmental temperature has been shown to affect the ability of mosquitoes to transmit numerous arboviruses and for Rift Valley fever virus (RVFV) in particular. We evaluated the effect of incubation temperatures ranging from 14-26ºC on infection, dissemination, and transmission rates for Culex ta...

  18. Clinical and laboratory features of dengue virus-infected travellers previously vaccinated against yellow fever

    NARCIS (Netherlands)

    Teichmann, Dieter; Göbels, Klaus; Niedrig, Matthias; Grobusch, Martin P.

    2003-01-01

    Dengue is a mosquito-borne viral infection endemic throughout the tropics and subtropics. The global prevalence of dengue has grown dramatically in recent years and it has become a major international public health concern. The close taxonomic relationships between yellow fever and dengue viruses

  19. Vertical transmission of Rift Valley Fever Virus without detectable maternal viremia

    NARCIS (Netherlands)

    Antonis, A.F.G.; Kortekaas, J.A.; Kant-Eenbergen, H.C.M.; Vloet, R.P.M.; Vogel-Brink, A.; Stockhofe, N.; Moormann, R.J.M.

    2013-01-01

    Rift Valley fever virus (RVFV) is a zoonotic bunyavirus that causes abortions in domesticated ruminants. Sheep breeds exotic to endemic areas are reportedly the most susceptible to RVFV infection. Within the scope of a risk assessment program of The Netherlands, we investigated the susceptibility of

  20. Antibodies against severe fever with Thrombocytopenia syndrome Virus in healthy persons, China, 2013

    NARCIS (Netherlands)

    Zhang Lei, Lei; Sun, J.; Yan, J.; Huakun, L.; Chai, C.Y.; Sun, Y.; Shao, B.; Jiang, J.D.; Chen, Z.; Kortekaas, J.A.; Zhang, Y.

    2014-01-01

    In June 2013, a subclinical infection with severe fever with thrombocytopenia syndrome virus (SFTSV) was detected in Zhejiang Province, China, prompting seroprevalence studies in 6 districts within the province. Of 986 healthy persons tested, 71 had IgG antibodies against SFTSV. This finding

  1. Appearance of reassortant European avian-origin H1 influenza A viruses of swine in Vietnam.

    Science.gov (United States)

    Takemae, N; Nguyen, P T; Le, V T; Nguyen, T N; To, T L; Nguyen, T D; Pham, V P; Vo, H V; Le, Q V T; Do, H T; Nguyen, D T; Uchida, Y; Saito, T

    2018-03-06

    Three subtypes-H1N1, H1N2 and H3N2-of influenza A viruses of swine (IAVs-S) are currently endemic in swine worldwide, but there is considerable genotypic diversity among each subtype and limited geographical distribution. Through IAVs-S monitoring in Vietnam, two H1N2 influenza A viruses were isolated from healthy pigs in Ba Ria-Vung Tau Province, Southern Vietnam, on 2 December 2016. BLAST and phylogenetic analyses revealed that their HA and NA genes were derived from those of European avian-like H1N2 IAVs-S that contained avian-origin H1 and human-like N2 genes, and were particularly closely related to those of IAVs-S circulating in the Netherlands, Germany or Denmark. In addition, the internal genes of these Vietnamese isolates were derived from human A(H1N1)pdm09 viruses, suggesting that the Vietnamese H1N2 IAVs-S are reassortants between European H1N2 IAVs-S and human A(H1N1)pdm09v. The appearance of European avian-like H1N2 IAVs-S in Vietnam marks their first transmission outside Europe. Our results and statistical analyses of the number of live pigs imported into Vietnam suggest that the European avian-like H1N2 IAVs-S may have been introduced into Vietnam with their hosts through international trade. These findings highlight the importance of quarantining imported pigs to impede the introduction of new IAVs-S. © 2018 Blackwell Verlag GmbH.

  2. Detection of antibodies to transmissible gastroenteritis virus of swine by modified autoradiographic test

    Energy Technology Data Exchange (ETDEWEB)

    Stepanek, J; Hampl, J; Franz, J; Mensik, P; Skrobak, F [Vyzkumny Ustav Veterinarniho Lekarstvi, Brno-Medlanky (Czechoslovakia)

    1982-08-01

    A modified method of autoradiographic determination of virus antibodies of gastroenteritis of swine was developed. It is based on the actual reaction between antigen bound in cells of the infected cell cultures and antibodies in tested sera, which is visualized by rabbit antibodies labelled with /sup 125/I (/sup 125/I RaSw IgG antibody) to porcine IgG, on a sensitive radiograph and evaluated by darkening at the point of positive immunological reaction. Specificity of the test and mutual comparability and reproducibility of the results were confirmed by examining the known positive and negative sera and by a comparison with the results of the virus-neutralization test. Of the 36 examined porcine blood sera, antibodies were only proved autoradiographically in the samples positive also by virus-neutralization. In experimentally infected pigs, the same dynamics of antibody production was recorded by the two tests. They were, however, demonstrated autoradiographically the eighth day after infection, while by virus neutralization test as late as 14th day. Their level increased gradually till 35th day after infection.

  3. Dengue fever (image)

    Science.gov (United States)

    Dengue fever, or West Nile fever, is a mild viral illness transmitted by mosquitoes which causes fever, ... second exposure to the virus can result in Dengue hemorrhagic fever, a life-threatening illness.

  4. Seroprevalence of hepatitis E in swine abattoir workers.

    African Journals Online (AJOL)

    The disease poses economic ... III and IV infect both swine and humans; and are re- ... associated with transmission in swine abattoir workers in ..... tal evidence for cross-species infection by swine hepatitis ... A novel virus in swine is closely.

  5. Case report: probable transmission of vaccine strain of yellow fever virus to an infant via breast milk

    OpenAIRE

    Kuhn, Susan; Twele-Montecinos, Loreto; MacDonald, Judy; Webster, Patricia; Law, Barbara

    2011-01-01

    The 17D yellow fever vaccine is a live-virus vaccine that has been in use since the 1940s. The incidence of encephalitis after yellow fever vaccination among young infants is much higher than among children older than nine months of age. Until recently, avoidance of vaccination by breastfeeding women who have received yellow fever vaccine had been based on theoretical grounds only. We report the probable transmission of vaccine strain of yellow fever virus from a mother to her infant through ...

  6. Swine-origin influenza A (H3N2) virus infection in two children--Indiana and Pennsylvania, July-August 2011.

    Science.gov (United States)

    2011-09-09

    Influenza A viruses are endemic in many animal species, including humans, swine, and wild birds, and sporadic cases of transmission of influenza A viruses between humans and animals do occur, including human infections with avian-origin influenza A viruses (i.e., H5N1 and H7N7) and swine-origin influenza A viruses (i.e., H1N1, H1N2, and H3N2). Genetic analysis can distinguish animal origin influenza viruses from the seasonal human influenza viruses that circulate widely and cause annual epidemics. This report describes two cases of febrile respiratory illness caused by swine-origin influenza A (H3N2) viruses identified on August 19 and August 26, 2011, and the current investigations. No epidemiologic link between the two cases has been identified, and although investigations are ongoing, no additional confirmed human infections with this virus have been detected. These viruses are similar to eight other swine-origin influenza A (H3N2) viruses identified from previous human infections over the past 2 years, but are unique in that one of the eight gene segments (matrix [M] gene) is from the 2009 influenza A (H1N1) virus. The acquisition of the M gene in these two swine-origin influenza A (H3N2) viruses indicates that they are "reassortants" because they contain genes of the swine-origin influenza A (H3N2) virus circulating in North American pigs since 1998 and the 2009 influenza A (H1N1) virus that might have been transmitted to pigs from humans during the 2009 H1N1 pandemic. However, reassortments of the 2009 influenza A (H1N1) virus with other swine influenza A viruses have been reported previously in swine. Clinicians who suspect influenza virus infection in humans with recent exposure to swine should obtain a nasopharyngeal swab from the patient for timely diagnosis at a state public health laboratory and consider empiric neuraminidase inhibitor antiviral treatment to quickly limit potential human transmission.

  7. Relevant Measures to Prevent the Spread of African Swine Fever in the European Union Domestic Pig Sector.

    Science.gov (United States)

    Jurado, Cristina; Martínez-Avilés, Marta; De La Torre, Ana; Štukelj, Marina; de Carvalho Ferreira, Helena Cardoso; Cerioli, Monica; Sánchez-Vizcaíno, José Manuel; Bellini, Silvia

    2018-01-01

    During the past decade, African swine fever (ASF) has spread from the Caucasus region to eastern European Union countries affecting domestic pig and wild boar populations. In order to avert ASF spread, mitigation measures targeting both populations have been established. However, despite these efforts, ASF has been reported in thirteen different countries (Georgia, Azerbaijan, Armenia, the Russian Federation, Ukraine, Belarus, Estonia, Latvia, Lithuania, Poland, Moldova, Czech Republic, and Romania). In the absence of an effective vaccine or treatment to ASF, introduction and spread of ASF onto domestic pig farms can only be prevented by strict compliance to control measures. This study systematically reviewed available measures to prevent the spread of ASF in the EU domestic pig sector distinguishing between commercial, non-commercial, and outdoor farms. The search was performed in PubMed and using a common browser. A total of 52 documents were selected for the final review process, which included scientific articles, reports, EU documents and official recommendations, among others. From this literature review, 37 measures were identified as preventive measures for the introduction and spread of ASF. Subsequently, these measures were assessed by ASF experts for their relevance in the mitigation of ASF spread on the three mentioned types of farms. All experts agreed that some of the important preventive measures for all three types of farms were: the identification of animals and farm records; strict enforcement of the ban on swill feeding; and containment of pigs, so as to not allow direct or indirect pig-pig and/or pig-wild boar contacts. Other important preventive measures for all farms were education of farmers, workers, and operators; no contact between farmers and farm staff and external pigs; appropriate removal of carcasses, slaughter residues, and food waste; proper disposal of manure and dead animals, and abstaining from hunting activities during the

  8. Relevant Measures to Prevent the Spread of African Swine Fever in the European Union Domestic Pig Sector

    Directory of Open Access Journals (Sweden)

    Cristina Jurado

    2018-04-01

    Full Text Available During the past decade, African swine fever (ASF has spread from the Caucasus region to eastern European Union countries affecting domestic pig and wild boar populations. In order to avert ASF spread, mitigation measures targeting both populations have been established. However, despite these efforts, ASF has been reported in thirteen different countries (Georgia, Azerbaijan, Armenia, the Russian Federation, Ukraine, Belarus, Estonia, Latvia, Lithuania, Poland, Moldova, Czech Republic, and Romania. In the absence of an effective vaccine or treatment to ASF, introduction and spread of ASF onto domestic pig farms can only be prevented by strict compliance to control measures. This study systematically reviewed available measures to prevent the spread of ASF in the EU domestic pig sector distinguishing between commercial, non-commercial, and outdoor farms. The search was performed in PubMed and using a common browser. A total of 52 documents were selected for the final review process, which included scientific articles, reports, EU documents and official recommendations, among others. From this literature review, 37 measures were identified as preventive measures for the introduction and spread of ASF. Subsequently, these measures were assessed by ASF experts for their relevance in the mitigation of ASF spread on the three mentioned types of farms. All experts agreed that some of the important preventive measures for all three types of farms were: the identification of animals and farm records; strict enforcement of the ban on swill feeding; and containment of pigs, so as to not allow direct or indirect pig–pig and/or pig–wild boar contacts. Other important preventive measures for all farms were education of farmers, workers, and operators; no contact between farmers and farm staff and external pigs; appropriate removal of carcasses, slaughter residues, and food waste; proper disposal of manure and dead animals, and abstaining from hunting

  9. Update on the Risk of Introduction of African Swine Fever by Wild Boar into Disease-Free European Union Countries.

    Science.gov (United States)

    Bosch, J; Rodríguez, A; Iglesias, I; Muñoz, M J; Jurado, C; Sánchez-Vizcaíno, J M; de la Torre, A

    2017-10-01

    Despite efforts to prevent the appearance and spread of African swine fever (ASF) in the European Union, several Member States are now affected (Lithuania, Poland, Latvia and Estonia). Disease appearance in 2014 was associated with multiple entrances linked to wild boar movement from endemic areas (EFSA Journal, 8, 2015, 1556), but the risk of new introductions remains high (Gallardo et al., Porcine Health Management, 1, and 21) as ASF continues to be active in endemic countries (Russian Federation, Belarus and Ukraine). Since 2014, the number of ASF notifications has increased substantially, particularly in wild boar (WB), in parallel with slow but constant geographical advance of the disease. This situation suggests a real risk of further disease spread into other Member States, posing a great threat to pig production in the EU. Following the principles of the risk-based veterinary surveillance, this article applies a methodology developed by De la Torre et al. (Transboundary and Emerging Diseases, 62, and 272) to assess the relative risk of new introductions of ASF by natural movements of WB according to the current epidemiological situation. This update incorporates the most recent available data and an improved version of the most important risk estimator: an optimized cartographic tool of WB distribution to analyse wild boar suitable habitat. The highest relative risk values were estimated for Slovakia (5) and Romania (5), followed by Finland (4), Czech Republic (3) and Germany (3). Relative risk for Romania and Finland is associated mainly with disease entrance from endemic areas such as the Russian Federation and Ukraine, where the disease is currently spreading; relative risk for Germany and Czech Republic is associated mainly with the potential progress of the disease through the EU, and relative risk for Slovakia is associated with both pathways. WB habitat is the most important risk estimator, whereas WB density is the least significant, suggesting

  10. Relevant Measures to Prevent the Spread of African Swine Fever in the European Union Domestic Pig Sector

    Science.gov (United States)

    Jurado, Cristina; Martínez-Avilés, Marta; De La Torre, Ana; Štukelj, Marina; de Carvalho Ferreira, Helena Cardoso; Cerioli, Monica; Sánchez-Vizcaíno, José Manuel; Bellini, Silvia

    2018-01-01

    During the past decade, African swine fever (ASF) has spread from the Caucasus region to eastern European Union countries affecting domestic pig and wild boar populations. In order to avert ASF spread, mitigation measures targeting both populations have been established. However, despite these efforts, ASF has been reported in thirteen different countries (Georgia, Azerbaijan, Armenia, the Russian Federation, Ukraine, Belarus, Estonia, Latvia, Lithuania, Poland, Moldova, Czech Republic, and Romania). In the absence of an effective vaccine or treatment to ASF, introduction and spread of ASF onto domestic pig farms can only be prevented by strict compliance to control measures. This study systematically reviewed available measures to prevent the spread of ASF in the EU domestic pig sector distinguishing between commercial, non-commercial, and outdoor farms. The search was performed in PubMed and using a common browser. A total of 52 documents were selected for the final review process, which included scientific articles, reports, EU documents and official recommendations, among others. From this literature review, 37 measures were identified as preventive measures for the introduction and spread of ASF. Subsequently, these measures were assessed by ASF experts for their relevance in the mitigation of ASF spread on the three mentioned types of farms. All experts agreed that some of the important preventive measures for all three types of farms were: the identification of animals and farm records; strict enforcement of the ban on swill feeding; and containment of pigs, so as to not allow direct or indirect pig–pig and/or pig–wild boar contacts. Other important preventive measures for all farms were education of farmers, workers, and operators; no contact between farmers and farm staff and external pigs; appropriate removal of carcasses, slaughter residues, and food waste; proper disposal of manure and dead animals, and abstaining from hunting activities during the

  11. Efficient cellular release of Rift Valley fever virus requires genomic RNA.

    Directory of Open Access Journals (Sweden)

    Mary E Piper

    2011-03-01

    Full Text Available The Rift Valley fever virus is responsible for periodic, explosive epizootics throughout sub-Saharan Africa. The development of therapeutics targeting this virus is difficult due to a limited understanding of the viral replicative cycle. Utilizing a virus-like particle system, we have established roles for each of the viral structural components in assembly, release, and virus infectivity. The envelope glycoprotein, Gn, was discovered to be necessary and sufficient for packaging of the genome, nucleocapsid protein and the RNA-dependent RNA polymerase into virus particles. Additionally, packaging of the genome was found to be necessary for the efficient release of particles, revealing a novel mechanism for the efficient generation of infectious virus. Our results identify possible conserved targets for development of anti-phlebovirus therapies.

  12. Swine Influenza Virus PA and Neuraminidase Gene Reassortment into Human H1N1 Influenza Virus Is Associated with an Altered Pathogenic Phenotype Linked to Increased MIP-2 Expression.

    Science.gov (United States)

    Dlugolenski, Daniel; Jones, Les; Howerth, Elizabeth; Wentworth, David; Tompkins, S Mark; Tripp, Ralph A

    2015-05-01

    Swine are susceptible to infection by both avian and human influenza viruses, and this feature is thought to contribute to novel reassortant influenza viruses. In this study, the influenza virus reassortment rate in swine and human cells was determined. Coinfection of swine cells with 2009 pandemic H1N1 virus (huH1N1) and an endemic swine H1N2 (A/swine/Illinois/02860/09) virus (swH1N2) resulted in a 23% reassortment rate that was independent of α2,3- or α2,6-sialic acid distribution on the cells. The reassortants had altered pathogenic phenotypes linked to introduction of the swine virus PA and neuraminidase (NA) into huH1N1. In mice, the huH1N1 PA and NA mediated increased MIP-2 expression early postinfection, resulting in substantial pulmonary neutrophilia with enhanced lung pathology and disease. The findings support the notion that swine are a mixing vessel for influenza virus reassortants independent of sialic acid distribution. These results show the potential for continued reassortment of the 2009 pandemic H1N1 virus with endemic swine viruses and for reassortants to have increased pathogenicity linked to the swine virus NA and PA genes which are associated with increased pulmonary neutrophil trafficking that is related to MIP-2 expression. Influenza A viruses can change rapidly via reassortment to create a novel virus, and reassortment can result in possible pandemics. Reassortments among subtypes from avian and human viruses led to the 1957 (H2N2 subtype) and 1968 (H3N2 subtype) human influenza pandemics. Recent analyses of circulating isolates have shown that multiple genes can be recombined from human, avian, and swine influenza viruses, leading to triple reassortants. Understanding the factors that can affect influenza A virus reassortment is needed for the establishment of disease intervention strategies that may reduce or preclude pandemics. The findings from this study show that swine cells provide a mixing vessel for influenza virus reassortment

  13. Molecular characterization of a novel reassortant H1N2 influenza virus containing genes from the 2009 pandemic human H1N1 virus in swine from eastern China.

    Science.gov (United States)

    Peng, Xiuming; Wu, Haibo; Xu, Lihua; Peng, Xiaorong; Cheng, Linfang; Jin, Changzhong; Xie, Tiansheng; Lu, Xiangyun; Wu, Nanping

    2016-06-01

    Pandemic outbreaks of H1N1 swine influenza virus have been reported since 2009. Reassortant H1N2 viruses that contain genes from the pandemic H1N1 virus have been isolated in Italy and the United States. However, there is limited information regarding the molecular characteristics of reassortant H1N2 swine influenza viruses in eastern China. Active influenza surveillance programs in Zhejiang Province identified a novel H1N2 influenza virus isolated from pigs displaying clinical signs of influenza virus infection. Whole-genome sequencing was performed and this strain was compared with other influenza viruses available in GenBank. Phylogenetic analysis suggested that the novel strain contained genes from the 2009 pandemic human H1N1 and swine H3N2 viruses. BALB/c mice were infected with the isolated virus to assess its virulence in mice. While the novel H1N2 isolate replicated well in mice, it was found to be less virulent. These results provide additional evidence that swine serve as intermediate hosts or 'mixing vessels' for novel influenza viruses. They also emphasize the importance of surveillance in the swine population for use as an early warning system for influenza outbreaks in swine and human populations.

  14. [Establishment of chemiluminescent enzyme immunoassay for detecting antibodies against foot-and-mouth disease virus serotype O in swine].

    Science.gov (United States)

    Cui, Chen; Huang, Ligang; Li, Jing; Zou, Xingqi; Zhu, Yuanyuan; Xie, Lei; Zhao, Qizu; Yang, Limin; Liu, Wenjun

    2016-11-25

    Recombinant structural protein VP1 of foot-and-mouth disease virus serotype O was expressed in Escherichia coli and then purified using Nickel affinity chromatography. A chemiluminescent enzyme immunoassay (CLEIA) method was established using the purified recombinant protein as coating antigen to detect antibody of foot-and-mouth disease virus serotype O in swine. The specificity of VP1-CLEIA method is 100%. The coefficients of variation in the plate and between plates are 1.10%-6.70% and 0.66%-4.80%, respectively. Comparing with the commercial indirect ELISA kit or liquid phase block ELISA kit, the calculated coincidence rate is 93.50% or 94.00%. The high specificity and stability suggested this detection method can be used to monitor the antibody level of foot-and-mouth disease virus serotype O in swine.

  15. Development of a primer–probe energy transfer based real-time PCR for the detection of Swine influenza virus

    DEFF Research Database (Denmark)

    Kowalczyk, Andrzej; Markowska-Daniel, Iwona; Rasmussen, Thomas Bruun

    2013-01-01

    Swine influenza virus (SIV) causes a contagious and requiring official notification disease of pigs and humans. In this study, a real-time reverse transcription-polymerase chain reaction (RT-PCR) assay based on primer–probe energy transfer (PriProET) for the detection of SIV RNA was developed...... of the specific product amplification. The assay is specific for influenza virus with a sensitivity of detection limit of approximately 10 copies of RNA by PCR. Based on serial dilutions of SIV, the detection limit of the assay was approximately 0.003 TCID50/ml for H1N1 A/Swine/Poland/KPR9/2004 virus. The Pri...

  16. Oral receptivity of Aedes aegypti from Cape Verde for yellow fever, dengue, and chikungunya viruses.

    Science.gov (United States)

    Vazeille, Marie; Yébakima, André; Lourenço-de-Oliveira, Ricardo; Andriamahefazafy, Barrysson; Correira, Artur; Rodrigues, Julio Monteiro; Veiga, Antonio; Moreira, Antonio; Leparc-Goffart, Isabelle; Grandadam, Marc; Failloux, Anna-Bella

    2013-01-01

    At the end of 2009, 21,313 cases of dengue-3 virus (DENV-3) were reported in the islands of Cape Verde, an archipelago located in the Atlantic Ocean 570 km from the coast of western Africa. It was the first dengue outbreak ever reported in Cape Verde. Mosquitoes collected in July 2010 in the city of Praia, on the island of Santiago, were identified morphologically as Aedes aegypti formosus. Using experimental oral infections, we found that this vector showed a moderate ability to transmit the epidemic dengue-3 virus, but was highly susceptible to chikungunya and yellow fever viruses.

  17. Crimean-Congo haemorrhagic fever virus infection in birds: field investigations in Senegal.

    Science.gov (United States)

    Zeller, H G; Cornet, J P; Camicas, J L

    1994-01-01

    In Senegal, wild ground-feeding birds are frequently infested with immature ticks. In two areas where numerous Crimean-Congo haemorrhagic fever (CCHF) virus isolations were obtained from Hyalomma marginatum rufipes adult ticks collected on ungulates, 175 birds were captured and sera collected. CCHF antibodies were detected by ELISA in 6/22 red-beaked hornbills (Tockus erythrorhynchus), 2/11 glossy starlings (Lamprotornis sp.) and 1/3 guinea fowls. The virus was isolated from H. m. rufipes nymphs collected on a hornbill. The role of wild ground-feeding birds in CCHF virus ecology in West Africa is discussed.

  18. Comparison of the usefulness of the CACO-2 cell line with standard substrates for isolation of swine influenza A viruses.

    Science.gov (United States)

    Chiapponi, Chiara; Zanni, Irene; Garbarino, Chiara; Barigazzi, Giuseppe; Foni, Emanuela

    2010-01-01

    Influenza A virus isolation is undertaken routinely in embryonated chicken eggs, but to improve virus detection various cell lines can be used. The CACO-2 cell line was compared to the MDCK cell line and embryonated chicken eggs for the isolation of H1N1, H1N2, H3N2 swine influenza A virus subtypes from clinical specimens. From 2006 to 2008, 104 influenza A samples found positive by PCR from 42 respiratory outbreaks in Italian swine farms were examined by virus isolation. Sixty swine influenza A viruses were isolated (16 H1N1, 28 H1N2 and 16 H3N2) and their growth behaviour on the different substrates was examined. 16/16 H1N1, 28/28 H1N2 and 8/16 of H3N2 viruses were isolated from the CACO-2 cell line, while 7/16 H1N1, 3/28 H1N2 and 16/16 H3N2 viruses were isolated using embryonated chicken eggs. Only 9/16 H1N1, 1/28 H1N2 and 6/16 H3N2 viruses replicated in MDCK cells. A link was found between viral hemagglutinin and the isolation rate on the various substrates. The CACO-2 line was statistically more sensitive (Fisher's exact test, pH1N2 subtypes. In contrast influenza A H3N2 virus was isolated more readily in embryonated chicken eggs than in cultured cells (Fisher's exact test, p<0.01).

  19. Viral meningitis epidemics and a single, recent, recombinant and anthroponotic origin of swine vesicular disease virus

    DEFF Research Database (Denmark)

    Bruhn, Christian Anders Wathne; Nielsen, Sandra Cathrine Abel; Samaniego Castruita, Jose Alfredo

    2015-01-01

    BACKGROUND AND OBJECTIVES: Swine vesicular disease virus (SVDV) is a close relative of the human Enterovirus B serotype, coxsackievirus B5. As the etiological agent of a significant emergent veterinary disease, several studies have attempted to explain its origin. However, several key questions...... and non-coding regions supports that SVDV has a recombinant origin between coxsackievirus B5 and another Enterovirus B serotype, most likely coxsackievirus A9. Extensive Bayesian sequence-based analysis of the time of the most recent common ancestor of all analysed sequences places this within a few years...... around 1961. Epidemiological evidence points to China as an origin, but there are no available samples to test this conclusively. CONCLUSIONS AND IMPLICATIONS: Historical investigation and the clinical aspects of the involved Enterovirus B serotypes, makes the current results consistent with a hypothesis...

  20. Reference gene selection for quantitative real-time PCR analysis in virus infected cells: SARS corona virus, Yellow fever virus, Human Herpesvirus-6, Camelpox virus and Cytomegalovirus infections

    Directory of Open Access Journals (Sweden)

    Müller Marcel A

    2005-02-01

    Full Text Available Abstract Ten potential reference genes were compared for their use in experiments investigating cellular mRNA expression of virus infected cells. Human cell lines were infected with Cytomegalovirus, Human Herpesvirus-6, Camelpox virus, SARS coronavirus or Yellow fever virus. The expression levels of these genes and the viral replication were determined by real-time PCR. Genes were ranked by the BestKeeper tool, the GeNorm tool and by criteria we reported previously. Ranking lists of the genes tested were tool dependent. However, over all, β-actin is an unsuitable as reference gene, whereas TATA-Box binding protein and peptidyl-prolyl-isomerase A are stable reference genes for expression studies in virus infected cells.

  1. Investigations into yellow fever virus and other arboviruses in the northern regions of Kenya.

    Science.gov (United States)

    Henderson, B E; Metselaar, D; Kirya, G B; Timms, G L

    1970-01-01

    Previous studies having shown an appreciable level of yellow fever immunity to exist in northern Kenya, further epidemiological and serological surveys were carried out there in 1968 in an attempt to define more clearly the distribution of yellow fever and to locate possible vector and reservoir hosts of the disease; these surveys also provided information on a number of other arboviruses.Altogether 436 sera from 5 areas in northern Kenya were screened by haemagglutination-inhibition tests with 8 antigens, and 107 of these sera by neutralization tests for Group-B arboviruses. Small numbers of yellow-fever-immune adults were found in Ileret, Garissa, Loglogo and Mikona. At Marsabit high proportions of immune adults and children were found among the Burgi tribe. As the Burgi are permanent agricultural workers on Marsabit Mountain, an entomological investigation was made, over 15 000 mosquitos being collected. From these, 13 strains of Pongola virus, 1 strain of Semliki Forest virus and an unidentified virus were isolated, but no yellow fever strains. Aedes africanus and Aedes simpsoni were not found at Marsabit; small numbers of Aedes aegypti were collected biting man. The vector potential of other mosquitos collected (particularly Mansonia africana, which is present throughout the year) is discussed.

  2. Chapare virus, a newly discovered arenavirus isolated from a fatal hemorrhagic fever case in Bolivia.

    Directory of Open Access Journals (Sweden)

    Simon Delgado

    2008-04-01

    Full Text Available A small focus of hemorrhagic fever (HF cases occurred near Cochabamba, Bolivia, in December 2003 and January 2004. Specimens were available from only one fatal case, which had a clinical course that included fever, headache, arthralgia, myalgia, and vomiting with subsequent deterioration and multiple hemorrhagic signs. A non-cytopathic virus was isolated from two of the patient serum samples, and identified as an arenavirus by IFA staining with a rabbit polyvalent antiserum raised against South American arenaviruses known to be associated with HF (Guanarito, Machupo, and Sabiá. RT-PCR analysis and subsequent analysis of the complete virus S and L RNA segment sequences identified the virus as a member of the New World Clade B arenaviruses, which includes all the pathogenic South American arenaviruses. The virus was shown to be most closely related to Sabiá virus, but with 26% and 30% nucleotide difference in the S and L segments, and 26%, 28%, 15% and 22% amino acid differences for the L, Z, N, and GP proteins, respectively, indicating the virus represents a newly discovered arenavirus, for which we propose the name Chapare virus. In conclusion, two different arenaviruses, Machupo and Chapare, can be associated with severe HF cases in Bolivia.

  3. Seroepidemiology and molecular characterization of hepatitis E virus infection in swine and occupationally exposed workers in Punjab, India.

    Science.gov (United States)

    Bansal, M; Kaur, S; Deka, D; Singh, R; Gill, J P S

    2017-12-01

    Hepatitis E virus (HEV) has two discrete epidemiological patterns: waterborne epidemics in developing countries only, caused by HEV genotype I, and sporadic zoonotic outbreaks in developing and developed countries caused by genotypes III and IV. This study was designed to investigate seroprevalence, molecular detection and the characterization of HEV by nested RT-PCR in swine as well as the occupational risk to exposed human population in Punjab state of north-western India. The occupational risk-exposed group comprised of swine farmers (organized - mixed feed feeders and unorganized - swill feeders), slaughterhouse workers, sewage workers and veterinary internes. During the study period, blood and faecal samples were collected from 320 swine and 360 humans with both high and low occupational exposure risks. The overall seroprevalence of swine HEV was 65.00%, with a significantly higher seropositivity in growing pigs (2-8 months of age). The prevalence of HEV RNA in swine faecal samples by nRT-PCR was 8.75% with a significantly higher detection in swill-fed pigs. With humans in the high occupational exposure risk population, significantly higher anti-HEV IgG seropositivity was observed (60.48%) as compared to control population (10.71%). Strong evidence of association between human anti-HEV IgG seropositivity and certain occupational exposure risk groups was observed (p workers and sewage workers have higher odds of HEV infection in this study region. Percentage of nucleotide similarity between swine and human HEV isolates was less than that found in countries with zoonotic HEV outbreaks. Molecular characterization revealed the circulation of G IV and G I genotypes among swine and human population in Punjab state, respectively. © 2017 Blackwell Verlag GmbH.

  4. Enzyme-Linked Immunosorbent Assay Using a Virus Type-Specific Peptide Based on a Subdomain of Envelope Protein Erns for Serologic Diagnosis of Pestivirus Infections in Swine

    Science.gov (United States)

    Langedijk, J. P. M.; Middel, W. G. J.; Meloen, R. H.; Kramps, J. A.; de Smit, J. A.

    2001-01-01

    Peptides deduced from the C-terminal end (residues 191 to 227) of pestivirus envelope protein Erns were used to develop enzyme-linked immunosorbent assays (ELISAs) to measure specifically antibodies against different types of pestiviruses. The choice of the peptide was based on the modular structure of the Erns protein, and the peptide was selected for its probable independent folding and good exposure, which would make it a good candidate for an antigenic peptide to be used in a diagnostic test. A solid-phase peptide ELISA which was cross-reactive for several types of pestivirus antibodies and which can be used for the general detection of pestivirus antibodies was developed. To identify type-specific pestivirus antibodies, a liquid-phase peptide ELISA, with a labeled, specific classical swine fever virus (CSFV) peptide and an unlabeled bovine viral diarrhea virus peptide to block cross-reactivity, was developed. Specificity and sensitivity of the liquid-phase peptide ELISA for CSFV were 98 and 100%, respectively. Because the peptide is a fragment of the Erns protein, it can be used to differentiate between infected and vaccinated animals when a vaccine based on the E2 protein, which is another pestivirus envelope protein, is used. PMID:11230402

  5. Characterization of a newly emerged genetic cluster of H1N1 and H1N2 swine influenza virus in the United States.

    Science.gov (United States)

    Vincent, Amy L; Ma, Wenjun; Lager, Kelly M; Gramer, Marie R; Richt, Juergen A; Janke, Bruce H

    2009-10-01

    H1 influenza A viruses that were distinct from the classical swine H1 lineage were identified in pigs in Canada in 2003–2004; antigenic and genetic characterization identified the hemagglutinin (HA) as human H1 lineage. The viruses identified in Canadian pigs were human lineage in entirety or double (human–swine) reassortants. Here, we report the whole genome sequence analysis of four human-like H1 viruses isolated from U.S. swine in 2005 and 2007. All four isolates were characterized as triple reassortants with an internal gene constellation similar to contemporary U.S. swine influenza virus (SIV), with HA and neuraminidase (NA) most similar to human influenza virus lineages. A 2007 human-like H1N1 was evaluated in a pathogenesis and transmission model and compared to a 2004 reassortant H1N1 SIV isolate with swine lineage HA and NA. The 2007 isolate induced disease typical of influenza virus and was transmitted to contact pigs; however, the kinetics and magnitude differed from the 2004 H1N1 SIV. This study indicates that the human-like H1 SIV can efficiently replicate and transmit in the swine host and now co-circulates with contemporary SIVs as a distinct genetic cluster of H1 SIV.

  6. Different evolutionary trends of swine H1N2 influenza viruses in Italy compared to European viruses.

    Science.gov (United States)

    Moreno, Ana; Gabanelli, Elena; Sozzi, Enrica; Lelli, Davide; Chiapponi, Chiara; Ciccozzi, Massimo; Zehender, Gianguglielmo; Cordioli, Paolo

    2013-12-01

    European H1N2 swine influenza viruses (EU H1N2SIVs) arose from multiple reassortment events among human H1N1, human H3N2, and avian influenza viruses. We investigated the evolutionary dynamics of 53 Italian H1N2 strains by comparing them with EU H1N2 SIVs. Hemagglutinin (HA) phylogeny revealed Italian strains fell into four groups: Group A and B (41 strains) had a human H1 similar to EU H1N2SIVs, which probably originated in 1986. However Group B (38 strains) formed a subgroup that had a two-amino acid deletion at positions 146/147 in HA. Group C (11 strains) contained an avian H1 that probably originated in 1996, and Group D (1 strain) had an H1 characteristic of the 2009 pandemic strain. Neuraminidase (NA) phylogeny suggested a series of genomic reassortments had occurred. Group A had an N2 that originated from human H3N2 in the late 1970s. Group B had different human N2 that most likely arose from a reassortment with the more recent human H3N2 virus, which probably occurred in 2000. Group C had an avian-like H1 combined with an N2 gene from one of EU H1N2SIVs, EU H3N2SIVs or Human H3N2. Group D was part of the EU H3N2SIVs clade. Although selection pressure for HA and NA was low, several positively selected sites were identified in both proteins, some of which were antigenic, suggesting selection influenced the evolution of SIV. The data highlight different evolutionary trends between European viruses and currently circulating Italian B strains and show the establishment of reassortant strains involving human viruses in Italian pigs.

  7. Clinical and epidemiologic characteristics of an outbreak of novel H1N1 (swine origin) influenza A virus among United States military beneficiaries.

    Science.gov (United States)

    Crum-Cianflone, Nancy F; Blair, Patrick J; Faix, Dennis; Arnold, John; Echols, Sara; Sherman, Sterling S; Tueller, John E; Warkentien, Tyler; Sanguineti, Gabriela; Bavaro, Mary; Hale, Braden R

    2009-12-15

    A novel swine-origin influenza A (H1N1) virus was identified in March 2009 and subsequently caused worldwide outbreaks. The San Diego region was an early focal point of the emerging pandemic. We describe the clinical and epidemiologic characteristics of this novel strain in a military population to assist in future outbreak prevention and control efforts. We performed an epidemiologic evaluation of novel H1N1 virus infections diagnosed in San Diego County among 96,258 local US military beneficiaries. The structured military medical system afforded the ability to obtain precise epidemiologic information on the impact on H1N1 virus infection in a population. The novel H1N1 virus was confirmed using real-time reverse transcriptase polymerase chain reaction (rRT-PCR). From 21 April through 8 May 2009, 761 patients presented with influenza-like illness and underwent rRT-PCR testing. Of these patients, 97 had confirmed novel H1N1 virus infection, with an incidence rate of 101 cases per 100,000 persons. The median age of H1N1 patients with H1N1 virus infection was 21 years (interquartile range, 15-25 years). Fever was a universal symptom in patients with H1N1 virus infection; other symptoms included cough (present in 96% of patients), myalgia or arthralgia (57%), and sore throat (51%). Sixty-eight (70%) of our patients had an identifiable epidemiologic link to another confirmed patient. The largest cluster of cases of H1N1 virus infection occurred on a Navy ship and involved 32 (8%) of 402 crew members; the secondary attack rate was 6%-14%. The rapid influenza testing that was used during this outbreak had a sensitivity of 51% and specificity of 98%, compared with rRT-PCR. Only 1 patient was hospitalized, and there were no deaths. A novel H1N1 influenza A virus caused a significant outbreak among military beneficiaries in San Diego County, including a significant cluster of cases onboard a Navy ship. The outbreak described here primarily affected adolescents and young

  8. Experimental infection with H1N1 European swine influenza virus protects pigs from an infection with the 2009 pandemic H1N1 human influenza virus.

    Science.gov (United States)

    Busquets, Núria; Segalés, Joaquim; Córdoba, Lorena; Mussá, Tufaria; Crisci, Elisa; Martín-Valls, Gerard E; Simon-Grifé, Meritxell; Pérez-Simó, Marta; Pérez-Maíllo, Monica; Núñez, Jose I; Abad, Francesc X; Fraile, Lorenzo; Pina, Sonia; Majó, Natalia; Bensaid, Albert; Domingo, Mariano; Montoya, María

    2010-01-01

    The recent pandemic caused by human influenza virus A(H1N1) 2009 contains ancestral gene segments from North American and Eurasian swine lineages as well as from avian and human influenza lineages. The emergence of this A(H1N1) 2009 poses a potential global threat for human health and the fact that it can infect other species, like pigs, favours a possible encounter with other influenza viruses circulating in swine herds. In Europe, H1N1, H1N2 and H3N2 subtypes of swine influenza virus currently have a high prevalence in commercial farms. To better assess the risk posed by the A(H1N1) 2009 in the actual situation of swine farms, we sought to analyze whether a previous infection with a circulating European avian-like swine A/Swine/Spain/53207/2004 (H1N1) influenza virus (hereafter referred to as SwH1N1) generated or not cross-protective immunity against a subsequent infection with the new human pandemic A/Catalonia/63/2009 (H1N1) influenza virus (hereafter referred to as pH1N1) 21 days apart. Pigs infected only with pH1N1 had mild to moderate pathological findings, consisting on broncho-interstitial pneumonia. However, pigs inoculated with SwH1N1 virus and subsequently infected with pH1N1 had very mild lung lesions, apparently attributed to the remaining lesions caused by SwH1N1 infection. These later pigs also exhibited boosted levels of specific antibodies. Finally, animals firstly infected with SwH1N1 virus and latter infected with pH1N1 exhibited undetectable viral RNA load in nasal swabs and lungs after challenge with pH1N1, indicating a cross-protective effect between both strains. © INRA, EDP Sciences, 2010.

  9. Spread and Control of Rift Valley Fever virus after accidental introduction in the Netherlands: a modelling study.

    NARCIS (Netherlands)

    Fischer, E.A.J.; Boender, G.J.; Koeijer, de A.A.; Nodelijk, G.; Roermund, van H.J.W.

    2011-01-01

    Rift Valley Fever (RVF) is a zoonotic vector-borne infection and causes a potentially severe disease in both humans and young animals. The Ministry of Economic Affairs, Agriculture and Innovation (EL&I) is interested in the risk of an outbreak of Rift Valley Fever virus (RVFV) for the

  10. Ebola hemorrhagic fever associated with novel virus strain, Uganda, 2007-2008.

    Science.gov (United States)

    Wamala, Joseph F; Lukwago, Luswa; Malimbo, Mugagga; Nguku, Patrick; Yoti, Zabulon; Musenero, Monica; Amone, Jackson; Mbabazi, William; Nanyunja, Miriam; Zaramba, Sam; Opio, Alex; Lutwama, Julius J; Talisuna, Ambrose O; Okware, Sam I

    2010-07-01

    During August 2007-February 2008, the novel Bundibugyo ebolavirus species was identified during an outbreak of Ebola viral hemorrhagic fever in Bundibugyo district, western Uganda. To characterize the outbreak as a requisite for determining response, we instituted a case-series investigation. We identified 192 suspected cases, of which 42 (22%) were laboratory positive for the novel species; 74 (38%) were probable, and 77 (40%) were negative. Laboratory confirmation lagged behind outbreak verification by 3 months. Bundibugyo ebolavirus was less fatal (case-fatality rate 34%) than Ebola viruses that had caused previous outbreaks in the region, and most transmission was associated with handling of dead persons without appropriate protection (adjusted odds ratio 3.83, 95% confidence interval 1.78-8.23). Our study highlights the need for maintaining a high index of suspicion for viral hemorrhagic fevers among healthcare workers, building local capacity for laboratory confirmation of viral hemorrhagic fevers, and institutionalizing standard precautions.

  11. Swine influenza virus infection dynamics in two pig farms; results of a longitudinal assessment

    Directory of Open Access Journals (Sweden)

    Simon-Grifé Meritxell

    2012-03-01

    Full Text Available Abstract In order to assess the dynamics of influenza virus infection in pigs, serological and virological follow-ups were conducted in two whole batches of pigs from two different farms (F1 and F2, from 3 weeks of age until market age. Anti-swine influenza virus (SIV antibodies (measured by ELISA and hemagglutination inhibition and nasal virus shedding (measured by RRT-PCR and isolation in embryonated chicken eggs and MDCK cells were carried out periodically. SIV isolates were subtyped and hemagglutinin and neuraminidase genes were partially sequenced and analyzed phylogenetically. In F1, four waves of viral circulation were detected, and globally, 62/121 pigs (51.2% were positive by RRT-PCR at least once. All F1 isolates corresponded to H1N1 subtype although hemagglutination inhibition results also revealed the presence of antibodies against H3N2. The first viral wave took place in the presence of colostral-derived antibodies. Nine pigs were positive in two non-consecutive sampling weeks, with two of the animals being positive with the same isolate. Phylogenetic analyses showed that different H1N1 variants circulated in that farm. In F2, only one isolate, H1N2, was detected and all infections were concentrated in a very short period of time, as assumed for a classic influenza outbreak. These findings led us to propose that influenza virus infection in pigs might present different patterns, from an epidemic outbreak to an endemic form with different waves of infections with a lower incidence.

  12. An Outbreak of Ebola Virus Disease in the Lassa Fever Zone.

    Science.gov (United States)

    Goba, Augustine; Khan, S Humarr; Fonnie, Mbalu; Fullah, Mohamed; Moigboi, Alex; Kovoma, Alice; Sinnah, Vandi; Yoko, Nancy; Rogers, Hawa; Safai, Siddiki; Momoh, Mambu; Koroma, Veronica; Kamara, Fatima K; Konowu, Edwin; Yillah, Mohamed; French, Issa; Mustapha, Ibraham; Kanneh, Franklyn; Foday, Momoh; McCarthy, Helena; Kallon, Tiangay; Kallon, Mustupha; Naiebu, Jenneh; Sellu, Josephine; Jalloh, Abdul A; Gbakie, Michael; Kanneh, Lansana; Massaly, James L B; Kargbo, David; Kargbo, Brima; Vandi, Mohamed; Gbetuwa, Momoh; Gevao, Sahr M; Sandi, John D; Jalloh, Simbirie C; Grant, Donald S; Blyden, Sylvia O; Crozier, Ian; Schieffelin, John S; McLellan, Susan L; Jacob, Shevin T; Boisen, Matt L; Hartnett, Jessica N; Cross, Robert W; Branco, Luis M; Andersen, Kristian G; Yozwiak, Nathan L; Gire, Stephen K; Tariyal, Ridhi; Park, Daniel J; Haislip, Allyson M; Bishop, Christopher M; Melnik, Lilia I; Gallaher, William R; Wimley, William C; He, Jing; Shaffer, Jeffrey G; Sullivan, Brian M; Grillo, Sonia; Oman, Scott; Garry, Courtney E; Edwards, Donna R; McCormick, Stephanie J; Elliott, Deborah H; Rouelle, Julie A; Kannadka, Chandrika B; Reyna, Ashley A; Bradley, Benjamin T; Yu, Haini; Yenni, Rachael E; Hastie, Kathryn M; Geisbert, Joan B; Kulakosky, Peter C; Wilson, Russell B; Oldstone, Michael B A; Pitts, Kelly R; Henderson, Lee A; Robinson, James E; Geisbert, Thomas W; Saphire, Erica Ollmann; Happi, Christian T; Asogun, Danny A; Sabeti, Pardis C; Garry, Robert F

    2016-10-15

     Kenema Government Hospital (KGH) has developed an advanced clinical and laboratory research capacity to manage the threat of Lassa fever, a viral hemorrhagic fever (VHF). The 2013-2016 Ebola virus (EBOV) disease (EVD) outbreak is the first to have occurred in an area close to a facility with established clinical and laboratory capacity for study of VHFs.  Because of its proximity to the epicenter of the EVD outbreak, which began in Guinea in March 2014, the KGH Lassa fever Team mobilized to establish EBOV surveillance and diagnostic capabilities.  Augustine Goba, director of the KGH Lassa laboratory, diagnosed the first documented case of EVD in Sierra Leone, on 25 May 2014. Thereafter, KGH received and cared for numbers of patients with EVD that quickly overwhelmed the capacity for safe management. Numerous healthcare workers contracted and lost their lives to EVD. The vast majority of subsequent EVD cases in West Africa can be traced back to a single transmission chain that includes this first diagnosed case.  Responding to the challenges of confronting 2 hemorrhagic fever viruses will require continued investments in the development of countermeasures (vaccines, therapeutic agents, and diagnostic assays), infrastructure, and human resources. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  13. Single-particle cryo-electron microscopy of Rift Valley fever virus.

    Science.gov (United States)

    Sherman, Michael B; Freiberg, Alexander N; Holbrook, Michael R; Watowich, Stanley J

    2009-04-25

    Rift Valley fever virus (RVFV; Bunyaviridae; Phlebovirus) is an emerging human and veterinary pathogen causing acute hepatitis in ruminants and has the potential to cause hemorrhagic fever in humans. We report a three-dimensional reconstruction of RVFV vaccine strain MP-12 (RVFV MP-12) by cryo-electron microcopy using icosahedral symmetry of individual virions. Although the genomic core of RVFV MP-12 is apparently poorly ordered, the glycoproteins on the virus surface are highly symmetric and arranged on a T=12 icosahedral lattice. Our RVFV MP-12 structure allowed clear identification of inter-capsomer contacts and definition of possible glycoprotein arrangements within capsomers. This structure provides a detailed model for phleboviruses, opens new avenues for high-resolution structural studies of the bunyavirus family, and aids the design of antiviral diagnostics and effective subunit vaccines.

  14. Single-particle cryo-electron microscopy of Rift Valley fever virus

    International Nuclear Information System (INIS)

    Sherman, Michael B.; Freiberg, Alexander N.; Holbrook, Michael R.; Watowich, Stanley J.

    2009-01-01

    Rift Valley fever virus (RVFV; Bunyaviridae; Phlebovirus) is an emerging human and veterinary pathogen causing acute hepatitis in ruminants and has the potential to cause hemorrhagic fever in humans. We report a three-dimensional reconstruction of RVFV vaccine strain MP-12 (RVFV MP-12) by cryo-electron microcopy using icosahedral symmetry of individual virions. Although the genomic core of RVFV MP-12 is apparently poorly ordered, the glycoproteins on the virus surface are highly symmetric and arranged on a T = 12 icosahedral lattice. Our RVFV MP-12 structure allowed clear identification of inter-capsomer contacts and definition of possible glycoprotein arrangements within capsomers. This structure provides a detailed model for phleboviruses, opens new avenues for high-resolution structural studies of the bunyavirus family, and aids the design of antiviral diagnostics and effective subunit vaccines.

  15. Protective role of host aquaporin 6 against Hazara virus, a model for Crimean-Congo hemorrhagic fever virus infection.

    Science.gov (United States)

    Molinas, Andrea; Mirazimi, Ali; Holm, Angelika; Loitto, Vesa M; Magnusson, Karl-Eric; Vikström, Elena

    2016-04-01

    Crimean-Congo hemorrhagic fever virus (CCHFV) is an arthropod-borne pathogen that causes infectious disease with severe hemorrhagic manifestations in vascular system in humans. The proper function of the cells in the vascular system is critically regulated by aquaporins (AQP), water channels that facilitate fluxes of water and small solutes across membranes. With Hazara virus as a model for CCHFV, we investigated the effects of viruses on AQP6 and the impact of AQP6 on virus infectivity in host cells, using transiently expressed GFP-AQP6 cells, immunofluorescent assay for virus detection, epifluorescent imaging of living cells and confocal microscopy. In GFP-AQP6 expressing cells, Hazara virus reduced both the cellular and perinuclear AQP6 distribution and changed the cell area. Infection of human cell with CCHFV strain IbAR 10200 downregulated AQP6 expression at mRNA level. Interestingly, the overexpression of AQP6 in host cells decreased the infectivity of Hazara virus, speaking for a protective role of AQP6. We suggest the possibility for AQP6 being a novel player in the virus-host interactions, which may lead to less severe outcomes of an infection. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. Distribution of sialic acid receptors and influenza A viruses of avian and swine origin and in experimentally infected pigs

    DEFF Research Database (Denmark)

    Trebbien, Ramona; Larsen, Lars Erik; Viuff, Birgitte M.

    2011-01-01

    Background: Pigs are considered susceptible to influenza A virus infections from different host origins because earlier studies have shown that they have receptors for both avian (sialic acid-alpha-2,3-terminal saccharides (SAalpha- 2,3)) and swine/human (SA-alpha-2,6) influenza viruses...... in the upper respiratory tract. Furthermore, experimental and natural infections in pigs have been reported with influenza A virus from avian and human sources. Methods: This study investigated the receptor distribution in the entire respiratory tract of pigs using specific lectins Maackia Amurensis (MAA) I...... and AIV virus was found, and this difference was in accordance with the distribution of the SA-alpha-2,6 and SA-alpha-2,3 receptor, respectively. The results indicated that the distribution of influenza A virus receptors in pigs are similar to that of humans and therefore challenge the theory that the pig...

  17. Distribution of sialic acid receptors and influenza A viruses of avian and swine origin and in experimentally infected pigs

    DEFF Research Database (Denmark)

    Trebbien, Ramona; Larsen, Lars Erik; Viuff, Birgitte M.

    2011-01-01

    Background: Pigs are considered susceptible to influenza A virus infections from different host origins because earlier studies have shown that they have receptors for both avian (sialic acid-alpha-2,3-terminal saccharides (SAalpha- 2,3)) and swine/human (SA-alpha-2,6) influenza viruses in the up......Background: Pigs are considered susceptible to influenza A virus infections from different host origins because earlier studies have shown that they have receptors for both avian (sialic acid-alpha-2,3-terminal saccharides (SAalpha- 2,3)) and swine/human (SA-alpha-2,6) influenza viruses...... and AIV virus was found, and this difference was in accordance with the distribution of the SA-alpha-2,6 and SA-alpha-2,3 receptor, respectively. The results indicated that the distribution of influenza A virus receptors in pigs are similar to that of humans and therefore challenge the theory that the pig...

  18. Swine influenza virus vaccines: to change or not to change-that's the question.

    Science.gov (United States)

    Van Reeth, Kristien; Ma, Wenjun

    2013-01-01

    Commercial vaccines currently available against swine influenza virus (SIV) are inactivated, adjuvanted, whole virus vaccines, based on H1N1 and/or H3N2 and/or H1N2 SIVs. In keeping with the antigenic and genetic differences between SIVs circulating in Europe and the US, the vaccines for each region are produced locally and contain different strains. Even within a continent, there is no standardization of vaccine strains, and the antigen mass and adjuvants can also differ between different commercial products. Recombinant protein vaccines against SIV, vector, and DNA vaccines, and vaccines attenuated by reverse genetics have been tested in experimental studies, but they have not yet reached the market. In this review, we aim to present a critical analysis of the performance of commercial inactivated and novel generation SIV vaccines in experimental vaccination challenge studies in pigs. We pay special attention to the differences between commercial SIV vaccines and vaccination attitudes in Europe and in North America, to the issue of vaccine strain selection and changes, and to the potential advantages of novel generation vaccines over the traditional killed SIV vaccines.

  19. The costs of preventive activities for exotic contagious diseases - A Danish case study of foot and mouth disease and swine fever

    DEFF Research Database (Denmark)

    Denver, Sigrid; Alban, Lis; Boklund, Anette

    2016-01-01

    The present paper provides an overview of the costs of preventive activities, currently undertaken in Denmark, related to foot and mouth disease (FMD) and classical and African swine fever (SF). Only costs held between outbreaks were included. Costs were divided into public costs and costs paid...... in a group of experts from universities, industry, and public authorities. The costs of each preventive activity were related to the type of activity, the number of times the activity was carried out and the share of costs that could be associated with FMD or SF. Uncertainty about parameters was incorporated...... by the pig and cattle industries, respectively. Data were retrieved from multiple sources such as databases, legal documents, official statistics, yearly reports and expert opinions. As no previous studies have assessed such costs, data collection and estimation procedures were discussed and decided upon...

  20. Oral infection of Aedes aegypti with yellow fever virus: geographic variation and genetic considerations.

    Science.gov (United States)

    Tabachnick, W J; Wallis, G P; Aitken, T H; Miller, B R; Amato, G D; Lorenz, L; Powell, J R; Beaty, B J

    1985-11-01

    Twenty-eight populations representing a worldwide distribution of Aedes aegypti were tested for their ability to become orally infected with yellow fever virus (YFV). Populations had been analyzed for genetic variations at 11 isozyme loci and assigned to one of 8 genetic geographic groups of Ae. aegypti. Infection rates suggest that populations showing isozyme genetic relatedness also demonstrate similarity to oral infection rates with YFV. The findings support the hypothesis that genetic variation exists for oral susceptibility to YFV in Ae. aegypti.

  1. Evidence for widespread infection of African bats with Crimean-Congo hemorrhagic fever-like viruses

    Czech Academy of Sciences Publication Activity Database

    Müller, M. A.; Devignot, S.; Lattwein, E.; Corman, V. M.; Maganga, G. D.; Gloza-Rausch, F.; Binger, T.; Vallo, Peter; Emmerich, P.; Cottontail, V. M.; Tschapka, M.; Oppong, S.; Drexler, J. F.; Weber, F.; Leroy, E. M.; Drosten, C.

    2016-01-01

    Roč. 6, č. 26637 (2016), č. článku 26637. ISSN 2045-2322 EU Projects: European Commission(XE) 278976 - ANTIGONE; European Commission(XE) 260427 - CCH Fever Institutional support: RVO:68081766 Keywords : sheep disease virus * family Bunyaviridae * serological relationships * antibody-response * migratory birds * rapid detection * viral load * ticks * nairovirus * genus Subject RIV: FN - Epidemiology, Contagious Diseases ; Clinical Immunology Impact factor: 4.259, year: 2016

  2. Potential for Mosquitoes (Diptera: Culicidae) From Florida to Transmit Rift Valley Fever Virus

    Science.gov (United States)

    2013-09-01

    signiÞcant disease and economic disruption. Rift Valley fever virus (RVFV), whichhasbeen responsible fornumerousoutbreaksof severe disease in ruminants and...is predominately a disease of domestic ruminants (cattle, goats, and sheep), where infection in pregnant animals usually results in abortion, and...www.cdc.gov/EID/ content /13/8/e1.htm). Britch, S.C.,K. J.Linthicum,A.Anyamba,C. J.Tucker,E.W. Pak, F. A. Maloney, K. Cobb, E. Stanwix, J. Humphries, A

  3. A Cartographic Tool for Managing African Swine Fever in Eurasia: Mapping Wild Boar Distribution Based on the Quality of Available Habitats.

    Science.gov (United States)

    Bosch, J; Iglesias, I; Muñoz, M J; de la Torre, A

    2017-12-01

    The current African swine fever (ASF) epidemic in Eurasia represents a risk for the swine industry with devastating socio-economic and political consequences. Wild boar appears to be a key factor in maintaining the disease in endemic areas (mainly the Russian Federation) and spreading the disease across borders, including within the European Union. To help predict and interpret the dynamics of ASF infection, we developed a standardized distribution map based on global land cover vegetation (GLOBCOVER) that quantifies the quality of available habitats (QAH) for wild boar across Eurasia as an indirect index for quantifying numbers of wild boar. QAHs were estimated using a seven-level scale based on expert opinion and found to correlate closely with georeferenced presence of wild boar (n = 22 362): the highest wild boar densities (74.47%) were found in areas at the two highest QAH levels, while the lowest densities (5.66%) were found in areas at the lowest QAH levels. Mapping notifications from 2007 to 2016 onto the QAH map showed that in endemic areas, 60% of ASF notifications occurred in domestic pigs, mostly in agricultural landscapes (QAHs 1.75 and 1) containing low-biosecurity domestic pig farms. In the EU, in contrast, 95% of ASF notifications occurred in wild boar, within natural landscapes (QAH 2). These results suggest that the QAH map can be a useful epi-tool for defining risk scenarios and identifying potential travel corridors for ASF. This tool will help inform resource allocation decisions and improve prevention, control and surveillance of ASF and potentially of other diseases affecting swine and wild boar in Eurasia. © 2016 Blackwell Verlag GmbH.

  4. Efficient, trans-complementing packaging systems for chimeric, pseudoinfectious dengue 2/yellow fever viruses

    International Nuclear Information System (INIS)

    Shustov, Alexandr V.; Frolov, Ilya

    2010-01-01

    In our previous studies, we have stated to build a new strategy for developing defective, pseudoinfectious flaviviruses (PIVs) and applying them as a new type of vaccine candidates. PIVs combined the efficiency of live vaccines with the safety of inactivated or subunit vaccines. The results of the present work demonstrate further development of chimeric PIVs encoding dengue virus 2 (DEN2V) glycoproteins and yellow fever virus (YFV)-derived replicative machinery as potential vaccine candidates. The newly designed PIVs have synergistically functioning mutations in the prM and NS2A proteins, which abolish processing of the latter proteins and make the defective viruses capable of producing either only noninfectious, immature and/or subviral DEN2V particles. The PIV genomes can be packaged to high titers into infectious virions in vitro using the NS1-deficient YFV helper RNAs, and both PIVs and helpers can then be passaged as two-component genome viruses at an escalating scale.

  5. Construction and characterization of a recombinant yellow fever virus stably expressing Gaussia luciferase

    Directory of Open Access Journals (Sweden)

    TELISSA C. KASSAR

    Full Text Available ABSTRACT Yellow fever is an arthropod-borne viral disease that still poses high public health concerns, despite the availability of an effective vaccine. The development of recombinant viruses is of utmost importance for several types of studies, such as those aimed to dissect virus-host interactions and to search for novel antiviral strategies. Moreover, recombinant viruses expressing reporter genes may greatly facilitate these studies. Here, we report the construction of a recombinant yellow fever virus (YFV expressing Gaussia luciferase (GLuc (YFV-GLuc. We show, through RT-PCR, sequencing and measurement of GLuc activity, that stability of the heterologous gene was maintained after six passages. Furthermore, a direct association between GLuc expression and viral replication was observed (r2=0.9967, indicating that measurement of GLuc activity may be used to assess viral replication in different applications. In addition, we evaluated the use of the recombinant virus in an antiviral assay with recombinant human alfa-2b interferon. A 60% inhibition of GLuc expression was observed in cells infected with YFV-GLuc and incubated with IFN alfa-2b. Previously tested on YFV inhibition by plaque assays indicated a similar fold-decrease in viral replication. These results are valuable as they show the stability of YFV-GLuc and one of several possible applications of this construct.

  6. Screening test for neutralizing antibodies against yellow fever virus, based on a flavivirus pseudotype.

    Directory of Open Access Journals (Sweden)

    Séverine Mercier-Delarue

    Full Text Available Given the possibility of yellow fever virus reintroduction in epidemiologically receptive geographic areas, the risk of vaccine supply disruption is a serious issue. New strategies to reduce the doses of injected vaccines should be evaluated very carefully in terms of immunogenicity. The plaque reduction test for the determination of neutralizing antibodies (PRNT is particularly time-consuming and requires the use of a confinement laboratory. We have developed a new test based on the use of a non-infectious pseudovirus (WN/YF17D. The presence of a reporter gene allows sensitive determination of neutralizing antibodies by flow cytometry. This WN/YF17D test was as sensitive as PRNT for the follow-up of yellow fever vaccinees. Both tests lacked specificity with sera from patients hospitalized for acute Dengue virus infection. Conversely, both assays were strictly negative in adults never exposed to flavivirus infection or vaccination, and in patients sampled some time after acute Dengue infection. This WN/YF17D test will be particularly useful for large epidemiological studies and for screening for neutralizing antibodies against yellow fever virus.

  7. Seroprevalence of yellow fever virus in selected health facilities in Western Kenya from 2010 to 2012.

    Science.gov (United States)

    Kwallah, Allan ole; Inoue, Shingo; Thairu-Muigai, Anne Wangari; Kuttoh, Nancy; Morita, Kouichi; Mwau, Matilu

    2015-01-01

    Yellow fever (YF), which is caused by a mosquito-borne virus, is an important viral hemorrhagic fever endemic in equatorial Africa and South America. Yellow fever virus (YFV) is the prototype of the family Flaviviridae and genus Flavivirus. The aim of this study was to determine the seroprevalence of YFV in selected health facilities in Western Kenya during the period 2010-2012. A total of 469 serum samples from febrile patients were tested for YFV antibodies using in-house IgM-capture ELISA, in-house indirect IgG ELISA, and 50% focus reduction neutralization test (FRNT50). The present study did not identify any IgM ELISA-positive cases, indicating absence of recent YFV infection in the area. Twenty-eight samples (6%) tested positive for YFV IgG, because of either YFV vaccination or past exposure to various flaviviruses including YFV. Five cases were confirmed by FRNT50; of these, 4 were either vaccination or natural infection during the YF outbreak in 1992-1993 or another period and 1 case was confirmed as a West Nile virus infection. Domestication and routine performance of arboviral differential diagnosis will help to address the phenomenon of pyrexia of unknown origin, contribute to arboviral research in developing countries, and enhance regular surveillance.

  8. Studies on the pathogenesis of fever with influenzal viruses. I. The appearance of an endogenous pyrogen in the blood following intravenous injection of virus.

    Science.gov (United States)

    ATKINS, E; HUANG, W C

    1958-03-01

    A substance with pyrogenic properties appears in the blood streams of rabbits made febrile by the intravenous inoculation of the PR8 strain of influenza A and Newcastle disease viruses (NDV). By means of a technique involving passive transfer of sera from animals given virus to recipient rabbits, the titer of circulating pyrogen was found to be closely correlated with the course of fever produced by virus. Certain properties of the pyrogen are described which differentiate it from the originally injected virus and suggest that the induced pyrogen is of endogenous origin. These properties resemble those of endogenous pyrogens occurring in other forms of experimental fever. The source of virus-induced pyrogen is unknown. In vitro incubation of virus with various constituents of the circulation did not result in the appearance of endogenous pyrogen. Granulocytopenia induced by HN(2) failed to influence either fever or the production of endogenous pyrogen in rabbits injected with NDV. Similarly, the intraperitoneal inoculation of NDV into prepared exudates did not modify the febrile response. These findings do not lend support to the possibility that the polymorphonuclear leukocyte is a significant source of endogenous pyrogen in virus-induced fever. It is concluded that the liberation of an endogenous pyrogen from some as yet undefined source is an essential step in the pathogenesis of fever caused by the influenza group of viruses.

  9. A Novel Benzodiazepine Compound Inhibits Yellow Fever Virus Infection by Specifically Targeting NS4B Protein.

    Science.gov (United States)

    Guo, Fang; Wu, Shuo; Julander, Justin; Ma, Julia; Zhang, Xuexiang; Kulp, John; Cuconati, Andrea; Block, Timothy M; Du, Yanming; Guo, Ju-Tao; Chang, Jinhong

    2016-09-21

    Although a highly effective vaccine is available, the number of yellow fever cases has increased over the past two decades, which highlights the pressing need for antiviral therapeutics. In a high throughput screening campaign, we identified an acetic acid benzodiazepine (BDAA) compound, which potently inhibits yellow fever virus (YFV). Interestingly, while treatment of YFV infected cultures with 2 μM of BDAA reduced the virion production by greater than 2 logs, the compound is not active against 21 other viruses from 14 different viral families. Selection and genetic analysis of drug resistant viruses revealed that substitution of proline at amino acid 219 (P219) of the nonstructural protein 4B (NS4B) with serine, threonine or alanine confers YFV resistance to BDAA without apparent loss of replication fitness in cultured mammalian cells. However, substitution of P219 with glycine confers BDAA resistance with significant loss of replication ability. Bioinformatics analysis predicts that the P219 localizes at the endoplasmic reticulum lumen side of the fifth putative trans-membrane domain of NS4B and the mutation may render the viral protein incapable of interacting with BDAA. Our studies thus revealed important role and structural basis for NS4B protein in supporting YFV replication. Moreover, in YFV-infected hamsters, oral administration of BDAA protected 90% of the animals from death, significantly reduced viral load by greater than 2 logs and attenuated viral infection-induced liver injury and body weight loss. The encouraging preclinical results thus warrant further development of BDAA or its derivatives as antiviral agents to treat yellow fever. Yellow fever is an acute viral hemorrhagic disease which threatens approximately one billion people living in tropical areas of Africa and Latin America. Although a highly effective yellow fever vaccine has been available for more than seven decades, the low vaccination rate fails to prevent outbreaks in at

  10. Climate Change and the Arboviruses: Lessons from the Evolution of the Dengue and Yellow Fever Viruses.

    Science.gov (United States)

    Tabachnick, Walter J

    2016-09-29

    The impact of anticipated changes in global climate on the arboviruses and the diseases they cause poses a significant challenge for public health. The past evolution of the dengue and yellow fever viruses provides clues about the influence of changes in climate on their future evolution. The evolution of both viruses has been influenced by virus interactions involving the mosquito species and the primate hosts involved in virus transmission, and by their domestic and sylvatic cycles. Information is needed on how viral genes in general influence phenotypic variance for important viral functions. Changes in global climate will alter the interactions of mosquito species with their primate hosts and with the viruses in domestic cycles, and greater attention should be paid to the sylvatic cycles. There is great danger for the evolution of novel viruses, such as new serotypes, that could compromise vaccination programs and jeopardize public health. It is essential to understand (a) both sylvatic and domestic cycles and (b) the role of virus genetic and environmental variances in shaping virus phenotypic variance to more fully assess the impact of global climate change.

  11. Near-complete genome sequencing of swine vesicular disease virus using the Roche GS FLX sequencing platform

    DEFF Research Database (Denmark)

    Nielsen, Sandra Cathrine Abel; Bruhn, Christian Anders Wathne; Samaniego Castruita, Jose Alfredo

    2014-01-01

    Swine vesicular disease virus (SVDV) is an enterovirus that is both genetically and antigenically closely related to human coxsackievirus B5 within the Picornaviridae family. SVDV is the causative agent of a highly contagious (though rarely fatal) vesicular disease in pigs. We report a rapid method...... with significant genetic distances within the same species of viruses. All reference mappings used an iterative method to avoid bias. Further verification was achieved through phylogenetic analysis against published SVDV genomes and additional Enterovirus B sequences. This approach allows high confidence...

  12. Isolation and molecular characterization of an H5N1 swine influenza virus in China in 2015.

    Science.gov (United States)

    Wu, Haibo; Yang, Fan; Lu, Rufeng; Xu, Lihua; Liu, Fumin; Peng, Xiuming; Wu, Nanping

    2018-03-01

    In 2015, an H5N1 influenza virus was isolated from a pig in Zhejiang Province, Eastern China. This strain was characterized by whole-genome sequencing with subsequent phylogenetic analysis. Phylogenetic analysis showed that all segments from this strain belonged to clade 2.3.2 and that it had received its genes from poultry influenza viruses in China. A Glu627Lys mutation associated with pathogenicity was observed in the PB2 protein. This strain was moderately pathogenic in mice and was able to replicate without prior adaptation. These results suggest that active surveillance of swine influenza should be used as an early warning system for influenza outbreaks in mammals.

  13. A Phylogeny-Based Global Nomenclature System and Automated Annotation Tool for H1 Hemagglutinin Genes from Swine Influenza A Viruses

    Science.gov (United States)

    Macken, Catherine A.; Lewis, Nicola S.; Van Reeth, Kristien; Brown, Ian H.; Swenson, Sabrina L.; Simon, Gaëlle; Saito, Takehiko; Berhane, Yohannes; Ciacci-Zanella, Janice; Pereda, Ariel; Davis, C. Todd; Donis, Ruben O.; Webby, Richard J.

    2016-01-01

    ABSTRACT The H1 subtype of influenza A viruses (IAVs) has been circulating in swine since the 1918 human influenza pandemic. Over time, and aided by further introductions from nonswine hosts, swine H1 viruses have diversified into three genetic lineages. Due to limited global data, these H1 lineages were named based on colloquial context, leading to a proliferation of inconsistent regional naming conventions. In this study, we propose rigorous phylogenetic criteria to establish a globally consistent nomenclature of swine H1 virus hemagglutinin (HA) evolution. These criteria applied to a data set of 7,070 H1 HA sequences led to 28 distinct clades as the basis for the nomenclature. We developed and implemented a web-accessible annotation tool that can assign these biologically informative categories to new sequence data. The annotation tool assigned the combined data set of 7,070 H1 sequences to the correct clade more than 99% of the time. Our analyses indicated that 87% of the swine H1 viruses from 2010 to the present had HAs that belonged to 7 contemporary cocirculating clades. Our nomenclature and web-accessible classification tool provide an accurate method for researchers, diagnosticians, and health officials to assign clade designations to HA sequences. The tool can be updated readily to track evolving nomenclature as new clades emerge, ensuring continued relevance. A common global nomenclature facilitates comparisons of IAVs infecting humans and pigs, within and between regions, and can provide insight into the diversity of swine H1 influenza virus and its impact on vaccine strain selection, diagnostic reagents, and test performance, thereby simplifying communication of such data. IMPORTANCE A fundamental goal in the biological sciences is the definition of groups of organisms based on evolutionary history and the naming of those groups. For influenza A viruses (IAVs) in swine, understanding the hemagglutinin (HA) genetic lineage of a circulating strain aids

  14. Construction of a recombinant baculovirus expressing swine hepatitis E Virus ORF2 and preliminary research on its immune effect.

    Science.gov (United States)

    Yang, Z; Hu, Y; Yuan, P; Yang, Y; Wang, K; Xie, L Y; Huang, S L; Liu, J; Ran, L; Song, Z H

    2018-03-01

    In the swine hepatitis E virus (HEV), open reading frame 2 (ORF2) is rich in antigenic determinants and neutralizing epitopes that could induce immune protection. We chose the Bac-to-Bac® Baculovirus Expression System to express fragments containing the critical neutralizing antigenic sites within the HEV ORF2 protein of pigs to obtain a recombinant baculovirus. The fragment of swine HEV ORF2 region (1198-1881bp) was cloned into vector pFastBacTM. A recombinant baculovirus, rBacmid-ORF2, was obtained after transposition and transfection. The molecular mass of the recombinant protein was 26 kDa. Mice were immunized by the intraperitoneal and oral routes with cell lysates of recombinant baculovirus rBacmid-ORF2. Serum and feces of the mice were collected separately at 0, 14, 28, and 42 d after immunization and the antibody levels of IgG and secretory IgA against swine HEV were determined using an enzyme-linked immunosorbent assay. The results suggested that rBacmid-ORF2 induced antibodies of the humoral and mucosal immune responses in mice and that the oral route was significantly superior to the intraperitoneal route. This is the first study to demonstrate that that recombinant baculovirus swine HEV ORF2 could induce humoral and mucosal immune responses in mice. Copyright© by the Polish Academy of Sciences.

  15. Comparative pathology of pigs infected with Korean H1N1, H1N2, or H3N2 swine influenza A viruses

    OpenAIRE

    Lyoo, Kwang-Soo; Kim, Jeong-Ki; Jung, Kwonil; Kang, Bo-Kyu; Song, Daesub

    2014-01-01

    Background The predominant subtypes of swine influenza A virus (SIV) in Korea swine population are H1N1, H1N2, and H3N2. The viruses are genetically close to the classical U.S. H1N1 and triple-reassortant H1N2 and H3N2 viruses, respectively. Comparative pathogenesis caused by Korean H1N1, H1N2, and H3N2 SIV was evaluated in this study. Findings The H3N2 infected pigs had severe scores of gross and histopathological lesions at post-inoculation days (PID) 2, and this then progressively decrease...

  16. Rapid detection and subtyping of European swine influenza viruses in porcine clinical samples by haemagglutinin- and neuraminidase-specific tetra- and triplex real-time RT-PCRs

    DEFF Research Database (Denmark)

    Henritzi, Dinah; Zhao, Na; Starick, Elke

    2016-01-01

    diagnostic methods which allow for cost-effective large-scale analysis. Methods New SIV haemagglutinin (HA) and neuraminidase (NA) subtype- and lineage-specific multiplex real-time RT-PCRs (RT-qPCR) have been developed and validated with reference virus isolates and clinical samples. Results A diagnostic....... Swine influenza viruses (SIV) are widespread in European domestic pig populations and evolve dynamically. Knowledge regarding occurrence, spread and evolution of potentially zoonotic SIV in Europe is poorly understood. Objectives Efficient SIV surveillance programmes depend on sensitive and specific......Background A diversifying pool of mammalian-adapted influenza A viruses (IAV) with largely unknown zoonotic potential is maintained in domestic swine populations worldwide. The most recent human influenza pandemic in 2009 was caused by a virus with genes originating from IAV isolated from swine...

  17. Yellow Fever Vaccine: What You Need to Know

    Science.gov (United States)

    ... How can I prevent yellow fever? Yellow fever vaccine Yellow fever vaccine can prevent yellow fever. Yellow fever vaccine ... such as those containing DEET. 3 Yellow fever vaccine Yellow fever vaccine is a live, weakened virus. It is ...

  18. First international external quality assessment of molecular detection of Crimean-Congo hemorrhagic fever virus.

    Directory of Open Access Journals (Sweden)

    Camille Escadafal

    Full Text Available Crimean-Congo hemorrhagic fever (CCHF is a zoonosis caused by a Nairovirus of the family Bunyaviridae. Infection is transmitted to humans mostly by Hyalomma ticks and also by direct contact with the blood or tissues of infected humans or viremic livestock. Clinical features usually include a rapid progression characterized by hemorrhage, myalgia and fever, with a lethality rate up to 30%. CCHF is one of the most widely distributed viral hemorrhagic fevers and has been reported in Africa, the Middle East and Asia, as well as parts of Europe. There is no approved vaccine or specific treatment against CCHF virus (CCHFV infections. In this context, an accurate diagnosis as well as a reliable surveillance of CCHFV infections is essential. Diagnostic techniques include virus culture, serology and molecular methods, which are now increasingly used. The European Network for the Diagnostics of "Imported" Viral Diseases organized the first international external quality assessment of CCHVF molecular diagnostics in 2011 to assess the efficiency and accurateness of CCHFV molecular methods applied by expert laboratories. A proficiency test panel of 15 samples was distributed to the participants including 10 different CCHFV preparations generated from infected cell cultures, a preparation of plasmid cloned with the nucleoprotein of CCHFV, two CCHFV RNA preparations and two negative controls. Forty-four laboratories worldwide participated in the EQA study and 53 data sets were received. Twenty data sets (38% met all criteria with optimal performance, 10 (19% with acceptable performance, while 23 (43% reported results showing a need for improvement. Differences in performance depended on the method used, the type of strain tested, the concentration of the sample tested and the laboratory performing the test. These results indicate that there is still a need for improving testing conditions and standardizing protocols for the molecular detection of Crimean

  19. A fatal yellow fever virus infection in China: description and lessons

    Science.gov (United States)

    Chen, Zhihai; Liu, Lin; Lv, Yanning; Zhang, Wei; Li, Jiandong; Zhang, Yi; Di, Tian; Zhang, Shuo; Liu, Jingyuan; Li, Jie; Qu, Jing; Hua, Wenhao; Li, Chuan; Wang, Peng; Zhang, Quanfu; Xu, Yanli; Jiang, Rongmeng; Wang, Qin; Chen, Lijuan; Wang, Shiwen; Pang, Xinghuo; Liang, Mifang; Ma, Xuejun; Li, Xingwang; Wang, Quanyi; Zhang, Fujie; Li, Dexin

    2016-01-01

    Yellow fever (YF) is a viral disease endemic to the tropical regions of Africa and South America. An outbreak of YF has been occurring in Angola, since the beginning of 2016. In March 2016, a 32-year-old Chinese man who returned from Angola was hospitalized and diagnosed with the first case of imported YF in China. Clinical observations, blood viral RNA detection, serological testing and treatments for the patient were performed daily. The virus was isolated in Vero cells, and the complete viral genome was sequenced and analyzed using the next-generation genomic sequencing platform. The patient presented with hemorrhagic fever, jaundice and oliguria at day 3 after onset, which rapidly progressed to multisystem organ failure with extremely elevated liver, pancreatic and myocardial enzymes. The patient died despite the intensive supportive treatments that were performed. A liver biopsy showed severe and multilobular necrosis. Viral RNA was detectable throughout the clinical course of the disease. Whole-genomic sequence analysis revealed that the virus belongs to the Angola71 genotype. Although the virus has been circulating in Angola for 45 years, only 14 amino-acid substitutions and no amino-acid changes were observed in the membrane and envelope proteins compared with the virus collected in 1971. The presence of this imported YF case in China indicated that with the increase in business travel among countries, YF outbreaks in Africa can lead to the international spread of the disease. The production and use of YF vaccines is, therefore, an urgent issue. PMID:27406389

  20. Subcellular distribution of swine vesicular disease virus proteins and alterations induced in infected cells: A comparative study with foot-and-mouth disease virus and vesicular stomatitis virus

    International Nuclear Information System (INIS)

    Martin-Acebes, Miguel A.; Gonzalez-Magaldi, Monica; Rosas, Maria F.; Borrego, Belen; Brocchi, Emiliana; Armas-Portela, Rosario; Sobrino, Francisco

    2008-01-01

    The intracellular distribution of swine vesicular disease virus (SVDV) proteins and the induced reorganization of endomembranes in IBRS-2 cells were analyzed. Fluorescence to new SVDV capsids appeared first upon infection, concentrated in perinuclear circular structures and colocalized to dsRNA. As in foot-and-mouth disease virus (FMDV)-infected cells, a vesicular pattern was predominantly found in later stages of SVDV capsid morphogenesis that colocalized with those of non-structural proteins 2C, 2BC and 3A. These results suggest that assembly of capsid proteins is associated to the replication complex. Confocal microscopy showed a decreased fluorescence to ER markers (calreticulin and protein disulfide isomerase), and disorganization of cis-Golgi gp74 and trans-Golgi caveolin-1 markers in SVDV- and FMDV-, but not in vesicular stomatitis virus (VSV)-infected cells. Electron microscopy of SVDV-infected cells at an early stage of infection revealed fragmented ER cisternae with expanded lumen and accumulation of large Golgi vesicles, suggesting alterations of vesicle traffic through Golgi compartments. At this early stage, FMDV induced different patterns of ER fragmentation and Golgi alterations. At later stages of SVDV cytopathology, cells showed a completely vacuolated cytoplasm containing vesicles of different sizes. Cell treatment with brefeldin A, which disrupts the Golgi complex, reduced SVDV (∼ 5 log) and VSV (∼ 4 log) titers, but did not affect FMDV growth. Thus, three viruses, which share target tissues and clinical signs in natural hosts, induce different intracellular effects in cultured cells

  1. Four-segmented Rift Valley fever virus-based vaccines can be applied safely in ewes during pregnancy

    NARCIS (Netherlands)

    Wichgers Schreur, Paul J.; Keulen, van Lucien; Kant-Eenbergen, Jet; Kortekaas, Jeroen

    2017-01-01

    Rift Valley fever virus (RVFV) causes severe and recurrent outbreaks on the African continent and the Arabian Peninsula and continues to expand its habitat. This mosquito-borne virus, belonging to the genus Phlebovirus of the family Bunyaviridae contains a tri-segmented negative-strand RNA

  2. Identification of a major non-structural protein in the nuclei of Rift Valley fever virus-infected cells.

    Science.gov (United States)

    Struthers, J K; Swanepoel, R

    1982-06-01

    A non-structural protein of mol. wt. 34 X 10(3) was demonstrated in the nuclei of Rift Valley fever virus-infected Vero cells by SDS-polyacrylamide gel electro-phoresis. The protein appears to correspond to the virus-induced antigen demonstrated by indirect immunofluorescence in intranuclear inclusions.

  3. European Surveillance Network for Influenza in Pigs: Surveillance Programs, Diagnostic Tools and Swine Influenza Virus Subtypes Identified in 14 European Countries from 2010 to 2013

    DEFF Research Database (Denmark)

    Simon, Gaelle; Larsen, Lars Erik; Duerrwald, Ralf

    2014-01-01

    : avian-like swine H1N1 (53.6%), human-like reassortant swine H1N2 (13%) and human-like reassortant swine H3N2 (9.1%), as well as pandemic A/H1N1 2009 (H1N1pdm) virus (10.3%). Viruses from these four lineages co-circulated in several countries but with very different relative levels of incidence....... For instance, the H3N2 subtype was not detected at all in some geographic areas whereas it was still prevalent in other parts of Europe. Interestingly, H3N2-free areas were those that exhibited highest frequencies of circulating H1N2 viruses. H1N1pdm viruses were isolated at an increasing incidence in some......Swine influenza causes concern for global veterinary and public health officials. In continuing two previous networks that initiated the surveillance of swine influenza viruses (SIVs) circulating in European pigs between 2001 and 2008, a third European Surveillance Network for Influenza in Pigs...

  4. Identification of New Protein Interactions between Dengue Fever Virus and Its Hosts, Human and Mosquito

    Science.gov (United States)

    Mairiang, Dumrong; Zhang, Huamei; Sodja, Ann; Murali, Thilakam; Suriyaphol, Prapat; Malasit, Prida; Limjindaporn, Thawornchai; Finley, Russell L.

    2013-01-01

    The four divergent serotypes of dengue virus are the causative agents of dengue fever, dengue hemorrhagic fever and dengue shock syndrome. About two-fifths of the world's population live in areas where dengue is prevalent, and thousands of deaths are caused by the viruses every year. Dengue virus is transmitted from one person to another primarily by the yellow fever mosquito, Aedes aegypti. Recent studies have begun to define how the dengue viral proteins interact with host proteins to mediate viral replication and pathogenesis. A combined analysis of these studies, however, suggests that many virus-host protein interactions remain to be identified, especially for the mosquito host. In this study, we used high-throughput yeast two-hybrid screening to identify mosquito and human proteins that physically interact with dengue proteins. We tested each identified host protein against the proteins from all four serotypes of dengue to identify interactions that are conserved across serotypes. We further confirmed many of the interactions using co-affinity purification assays. As in other large-scale screens, we identified some previously detected interactions and many new ones, moving us closer to a complete host – dengue protein interactome. To help summarize and prioritize the data for further study, we combined our interactions with other published data and identified a subset of the host-dengue interactions that are now supported by multiple forms of evidence. These data should be useful for understanding the interplay between dengue and its hosts and may provide candidates for drug targets and vector control strategies. PMID:23326450

  5. Identification of new protein interactions between dengue fever virus and its hosts, human and mosquito.

    Science.gov (United States)

    Mairiang, Dumrong; Zhang, Huamei; Sodja, Ann; Murali, Thilakam; Suriyaphol, Prapat; Malasit, Prida; Limjindaporn, Thawornchai; Finley, Russell L

    2013-01-01

    The four divergent serotypes of dengue virus are the causative agents of dengue fever, dengue hemorrhagic fever and dengue shock syndrome. About two-fifths of the world's population live in areas where dengue is prevalent, and thousands of deaths are caused by the viruses every year. Dengue virus is transmitted from one person to another primarily by the yellow fever mosquito, Aedes aegypti. Recent studies have begun to define how the dengue viral proteins interact with host proteins to mediate viral replication and pathogenesis. A combined analysis of these studies, however, suggests that many virus-host protein interactions remain to be identified, especially for the mosquito host. In this study, we used high-throughput yeast two-hybrid screening to identify mosquito and human proteins that physically interact with dengue proteins. We tested each identified host protein against the proteins from all four serotypes of dengue to identify interactions that are conserved across serotypes. We further confirmed many of the interactions using co-affinity purification assays. As in other large-scale screens, we identified some previously detected interactions and many new ones, moving us closer to a complete host - dengue protein interactome. To help summarize and prioritize the data for further study, we combined our interactions with other published data and identified a subset of the host-dengue interactions that are now supported by multiple forms of evidence. These data should be useful for understanding the interplay between dengue and its hosts and may provide candidates for drug targets and vector control strategies.

  6. Identification of new protein interactions between dengue fever virus and its hosts, human and mosquito.

    Directory of Open Access Journals (Sweden)

    Dumrong Mairiang

    Full Text Available The four divergent serotypes of dengue virus are the causative agents of dengue fever, dengue hemorrhagic fever and dengue shock syndrome. About two-fifths of the world's population live in areas where dengue is prevalent, and thousands of deaths are caused by the viruses every year. Dengue virus is transmitted from one person to another primarily by the yellow fever mosquito, Aedes aegypti. Recent studies have begun to define how the dengue viral proteins interact with host proteins to mediate viral replication and pathogenesis. A combined analysis of these studies, however, suggests that many virus-host protein interactions remain to be identified, especially for the mosquito host. In this study, we used high-throughput yeast two-hybrid screening to identify mosquito and human proteins that physically interact with dengue proteins. We tested each identified host protein against the proteins from all four serotypes of dengue to identify interactions that are conserved across serotypes. We further confirmed many of the interactions using co-affinity purification assays. As in other large-scale screens, we identified some previously detected interactions and many new ones, moving us closer to a complete host - dengue protein interactome. To help summarize and prioritize the data for further study, we combined our interactions with other published data and identified a subset of the host-dengue interactions that are now supported by multiple forms of evidence. These data should be useful for understanding the interplay between dengue and its hosts and may provide candidates for drug targets and vector control strategies.

  7. Evolutionary and molecular analysis of the emergent severe fever with thrombocytopenia syndrome virus.

    Science.gov (United States)

    Lam, Tommy Tsan-Yuk; Liu, Wei; Bowden, Thomas A; Cui, Ning; Zhuang, Lu; Liu, Kun; Zhang, Yao-Yun; Cao, Wu-Chun; Pybus, Oliver G

    2013-03-01

    In 2009, a novel Bunyavirus, called severe fever with thrombocytopenia syndrome virus (SFTSV) was identified in the vicinity of Huaiyangshan, China. Clinical symptoms of this zoonotic virus included severe fever, thrombocytopenia, and leukocytopenia, with a mortality rate of ~10%. By the end of 2011 the disease associated with this pathogen had been reported from eleven Chinese provinces and human-to-human transmission suspected. However, current understanding of the evolution and molecular epidemiology of SFTSV before and after its identification is limited. To address this we undertake phylogenetic, evolutionary and structural analyses of all available SFTSV genetic sequences, including a new SFTSV complete genome isolated from a patient from Henan in 2011. Our discovery of a mosaic L segment sequence, which is descended from two major circulating lineages of SFTSV in China, represents the first evidence that homologous recombination plays a role in SFTSV evolution. Selection analyses indicate that negative selection is predominant in SFTSV genes, yet differences in selective forces among genes are consistent between Phlebovirus species. Further analysis reveals structural conservation between SFTSV and Rift Valley fever virus in the residues of their nucleocapsids that are responsible for oligomerisation and RNA-binding, suggesting the viruses share similar modes of higher-order assembly. We reconstruct the epidemic history of SFTSV using molecular clock and coalescent-based methods, revealing that the extant SFTSV lineages originated 50-150 years ago, and that the viral population experienced a recent growth phase that concurs with and extends the earliest serological reports of SFTSV infection. Taken together, our combined structural and phylogenetic analyses shed light into the evolutionary behaviour of SFTSV in the context of other, better-known, pathogenic Phleboviruses. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. The yellow fever 17D virus as a platform for new live attenuated vaccines.

    Science.gov (United States)

    Bonaldo, Myrna C; Sequeira, Patrícia C; Galler, Ricardo

    2014-01-01

    The live-attenuated yellow fever 17D virus is one of the most outstanding human vaccines ever developed. It induces efficacious immune responses at a low production cost with a well-established manufacture process. These advantages make the YF17D virus attractive as a vector for the development of new vaccines. At the beginning of vector development studies, YF17D was genetically manipulated to express other flavivirus prM and E proteins, components of the viral envelope. While these 17D recombinants are based on the substitution of equivalent YF17D genes, other antigens from unrelated pathogens have also been successfully expressed and delivered by recombinant YF17D viruses employing alternative strategies for genetic manipulation of the YF17D genome. Herein, we discuss these strategies in terms of possibilities of single epitope or larger sequence expression and the main properties of these replication-competent viral platforms.

  9. [Serological detection of Brucella suis, influenza virus and Aujeszky's disease virus in backyard and small swine holders in Argentina].

    Science.gov (United States)

    Dibarbora, Marina; Cappuccio, Javier A; Aznar, María N; Bessone, Fernando A; Piscitelli, Hernán; Pereda, Ariel J; Pérez, Daniel R

    Farmers raising less than 100 sows represent more than 99% of swine producers in Argentina, although little is known about their sanitary status and productive characteristics in the country. Sanitary and productive information was obtained. Furthermore, samples for serological studies were taken to detect antibodies against Brucella suis (Bs), Aujeszky's disease virus (AV) and influenza virus (IV) in 68 backyard and small producers with less than 100 sows located in the north, central and south regions of Argentina. Antibodies against H1 pandemic were detected in 80% of the farms while 11%, 11.7% and 6.0% of the producers were positive to influenza H3 cluster 2, AV and Bs, respectively. None of the producers was aware of the risk factors concerning the transmission of diseases from pigs to humans. A percentage of 47% of them buy pigs for breeding from other farmers and markets. With regard to biosecurity measures, only 16% of the farms had perimeter fences. The results of this study demonstrate that productive characterization and disease surveys are important to improve productivity and to reduce the risk of disease transmission among animals and humans. The study of sanitary status and risk factors is necessary for better control and eradication of diseases in backyard or small producers. More representative studies at country level should be carried out to detect the pathogensthat circulate and, with this knowledge, to implement prevention and control measures. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  10. [Phylogenetic analysis of human/swine/avian gene reassortant H1N2 influenza A virus isolated from a pig in China].

    Science.gov (United States)

    Chen, Yixiang; Meng, Xueqiong; Liu, Qi; Huang, Xia; Huang, Shengbin; Liu, Cuiquan; Shi, Kaichuang; Guo, Jiangang; Chen, Fangfang; Hu, Liping

    2008-04-01

    Our aim in this study was to determine the genetic characterization and probable origin of the H1N2 swine influenza virus (A/Swine/Guangxi/13/2006) (Sw/GX/13/06) from lung tissue of a pig in Guangxi province, China. Eight genes of Sw/GX/13/06 were cloned and genetically analyzed. The hemagglutinin (HA), nucleoprotein (NP), matrix (M) and non-structural (NS) genes of Sw/GX/13/06 were most closely related to genes from the classical swine H1N1 influenza virus lineage. The neuraminidase (NA) and PB1 genes were most closely related to the corresponding genes from the human influenza H3N2 virus lineage. The remaining two genes PA and PB2 polymerase genes were most closely related to the genes from avian influenza virus lineage. Phylogenetic analyses revealed that Sw/GX/13/06 was a human/swine/avian H1N2 virus, and closely related to H1N2 viruses isolated from pigs in United States (1999-2001) and Korea (2002). To our knowledge, Sw/GX/13/06 was the first triple-reassortant H1N2 influenza A virus isolated from a pig in China. Whether the Sw/GX/13/06 has a potential threat to breeding farm and human health remains to be further investigated.

  11. Preliminary mapping of non-conserved epitopes on envelope glycoprotein E2 of bovine viral diarrhea virus type 1 and 2

    NARCIS (Netherlands)

    Jelsma, H.; Loeffen, W.L.A.; Beuningen, van A.R.; Rijn, van P.A.

    2013-01-01

    Bovine viral diarrhea virus (BVDV) belongs together with Classical swine fever virus (CSFV) and Border disease virus (BDV) to the genus Pestivirus in the Flaviviridae family. BVDV has been subdivided into two different species, BVDV1 and BVDV2 based on phylogenetic analysis. Subsequent

  12. Transmission dynamics of pandemic influenza A(H1N1)pdm09 virus in humans and swine in backyard farms in Tumbes, Peru.

    Science.gov (United States)

    Tinoco, Yeny O; Montgomery, Joel M; Kasper, Mathew R; Nelson, Martha I; Razuri, Hugo; Guezala, Maria C; Azziz-Baumgartner, Eduardo; Widdowson, Marc-Alain; Barnes, John; Gilman, Robert H; Bausch, Daniel G; Gonzalez, Armando E

    2016-01-01

    We aimed to determine the frequency of pH1N1 transmission between humans and swine on backyard farms in Tumbes, Peru. Two-year serial cross-sectional study comprising four sampling periods: March 2009 (pre-pandemic), October 2009 (peak of the pandemic in Peru), April 2010 (1st post-pandemic period), and October 2011 (2nd post-pandemic period). Backyard swine serum, tracheal swabs, and lung sample were collected during each sampling period. We assessed current and past pH1N1 infection in swine through serological testing, virus culture, and RT-PCR and compared the results with human incidence data from a population-based active surveillance cohort study in Peru. Among 1303 swine sampled, the antibody prevalence to pH1N1 was 0% pre-pandemic, 8% at the peak of the human pandemic (October 2009), and 24% in April 2010 and 1% in October 2011 (post-pandemic sampling periods). Trends in swine seropositivity paralleled those seen in humans in Tumbes. The pH1N1 virus was isolated from three pigs during the peak of the pandemic. Phylogenetic analysis revealed that these viruses likely represent two separate human-to-swine transmission events in backyard farm settings. Our findings suggest that human-to-swine pH1N1 transmission occurred during the pandemic among backyard farms in Peru, emphasizing the importance of interspecies transmission in backyard pig populations. Continued surveillance for influenza viruses in backyard farms is warranted. © 2015 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

  13. Evaluation of the zoonotic potential of a novel reassortant H1N2 swine influenza virus with gene constellation derived from multiple viral sources.

    Science.gov (United States)

    Lee, Jee Hoon; Pascua, Philippe Noriel Q; Decano, Arun G; Kim, Se Mi; Park, Su-Jin; Kwon, Hyeok-Il; Kim, Eun-Ha; Kim, Young-Il; Kim, HyongKyu; Kim, Seok-Yong; Song, Min-Suk; Jang, Hyung-Kwan; Park, Bong Kyun; Choi, Young Ki

    2015-08-01

    In 2011-2012, contemporary North American-like H3N2 swine influenza viruses (SIVs) possessing the 2009 pandemic H1N1 matrix gene (H3N2pM-like virus) were detected in domestic pigs of South Korea where H1N2 SIV strains are endemic. More recently, we isolated novel reassortant H1N2 SIVs bearing the Eurasian avian-like swine H1-like hemagglutinin and Korean swine H1N2-like neuraminidase in the internal gene backbone of the H3N2pM-like virus. In the present study, we clearly provide evidence on the genetic origins of the novel H1N2 SIVs virus through genetic and phylogenetic analyses. In vitro studies demonstrated that, in comparison with a pre-existing 2012 Korean H1N2 SIV [A/swine/Korea/CY03-11/2012 (CY03-11/2012)], the 2013 novel reassortant H1N2 isolate [A/swine/Korea/CY0423/2013 (CY0423-12/2013)] replicated more efficiently in differentiated primary human bronchial epithelial cells. The CY0423-12/2013 virus induced higher viral titers than the CY03-11/2012 virus in the lungs and nasal turbinates of infected mice and nasal wash samples of ferrets. Moreover, the 2013 H1N2 reassortant, but not the intact 2012 H1N2 virus, was transmissible to naïve contact ferrets via respiratory-droplets. Noting that the viral precursors have the ability to infect humans, our findings highlight the potential threat of a novel reassortant H1N2 SIV to public health and underscore the need to further strengthen influenza surveillance strategies worldwide, including swine populations. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Ebola virus: the role of macrophages and dendritic cells in the pathogenesis of Ebola hemorrhagic fever.

    Science.gov (United States)

    Bray, Mike; Geisbert, Thomas W

    2005-08-01

    Ebola hemorrhagic fever is a severe viral infection characterized by fever, shock and coagulation defects. Recent studies in macaques show that major features of illness are caused by effects of viral replication on macrophages and dendritic cells. Infected macrophages produce proinflammatory cytokines, chemokines and tissue factor, attracting additional target cells and inducing vasodilatation, increased vascular permeability and disseminated intravascular coagulation. However, they cannot restrict viral replication, possibly because of suppression of interferon responses. Infected dendritic cells also secrete proinflammatory mediators, but cannot initiate antigen-specific responses. In consequence, virus disseminates to these and other cell types throughout the body, causing multifocal necrosis and a syndrome resembling septic shock. Massive "bystander" apoptosis of natural killer and T cells further impairs immunity. These findings suggest that modifying host responses would be an effective therapeutic strategy, and treatment of infected macaques with a tissue-factor inhibitor reduced both inflammation and viral replication and improved survival.

  15. Rift Valley fever virus: strategies for maintenance, survival and vertical transmission in mosquitoes.

    Science.gov (United States)

    Lumley, Sarah; Horton, Daniel L; Hernandez-Triana, Luis L M; Johnson, Nicholas; Fooks, Anthony R; Hewson, Roger

    2017-05-01

    Rift Valley fever virus (RVFV) is a mosquito-borne arbovirus causing severe disease in humans and ruminants. Spread of RVFV out of Africa has raised concerns that it could emerge in Europe or the USA. Virus persistence is dependent on successful infection of, replication in, and transmission to susceptible vertebrate and invertebrate hosts, modulated by virus-host and vector-virus interactions. The principal accepted theory for the long-term maintenance of RVFV involves vertical transmission (VT) of virus to mosquito progeny, with the virus surviving long inter-epizootic periods within the egg. This VT hypothesis, however, is yet to be comprehensively proven. Here, evidence for and against the VT of RVFV is reviewed along with the identification of factors limiting its detection in natural and experimental data. The observations of VT for other arboviruses in the genera Alphavirus, Flavivirus and Orthobunyavirus are discussed within the context of RVFV. The review concludes that VT of RVFV is likely but that current data are insufficient to irrefutably prove this hypothesis.

  16. Attenuation of Recombinant Yellow Fever 17D Viruses Expressing Foreign Protein Epitopes at the Surface

    Science.gov (United States)

    Bonaldo, Myrna C.; Garratt, Richard C.; Marchevsky, Renato S.; Coutinho, Evandro S. F.; Jabor, Alfredo V.; Almeida, Luís F. C.; Yamamura, Anna M. Y.; Duarte, Adriana S.; Oliveira, Prisciliana J.; Lizeu, Jackeline O. P.; Camacho, Luiz A. B.; Freire, Marcos S.; Galler, Ricardo

    2005-01-01

    The yellow fever (YF) 17D vaccine is a live attenuated virus. Three-dimensional (3D) homology modeling of the E protein structure from YF 17D virus and its comparison with that from tick-borne encephalitis virus revealed that it is possible to accommodate inserts of different sizes and amino acid compositions in the flavivirus E protein fg loop. This is consistent with the 3D structures of both the dimeric and trimeric forms in which the fg loop lies exposed to solvents. We demonstrate here that YF 17D viruses bearing foreign humoral (17D/8) and T-cell (17D/13) epitopes, which vary in sequence and length, displayed growth restriction. It is hypothesized that interference with the dimer-trimer transition and with the formation of a ring of such trimers in order to allow fusion compromises the capability of the E protein to induce fusion of viral and endosomal membranes, and a slower rate of fusion may delay the extent of virus production. This would account for the lower levels of replication in cultured cells and of viremia in monkeys, as well as for the more attenuated phenotype of the recombinant viruses in monkeys. Testing of both recombinant viruses (17D/8 and 17D/13) for monkey neurovirulence also suggests that insertion at the 17D E protein fg loop does not compromise the attenuated phenotype of YF 17D virus, further confirming the potential use of this site for the development of new live attenuated 17D virus-based vaccines. PMID:15956601

  17. The influence of experimental infection of gilts with swine H1N2 influenza A virus during the second month of gestation on the course of pregnancy, reproduction parameters and clinical status.

    Science.gov (United States)

    Kwit, Krzysztof; Pomorska-Mól, Małgorzata; Markowska-Daniel, Iwona

    2014-06-04

    The course of swine influenza in pigs is reported to be similar to human influenza. Occasionally abortions and other reproduction disorders have been associated with influenza A virus (IAV) infection in pigs. Abortions may be a consequence of high fever, pro-inflammatory cytokines or transplacental transmission of the virus.The role of IAV in the complications observed during pregnancy has been scanty and the true importance of this agent as a cause of reproductive problems in swine is not known. The aim was to determine the possible involvement of swine H1N2 IAV strain on reproductive disorders in pregnant gilts under experimental conditions. The gestation length was from 113 to 116 days, no abortion or any other reproduction disorders were noted. A PCR assay confirms the presence of IAV in the nasal swabs taken from inoculated gilts between 1 and 5 dpi. In the nasal swabs from control gilts and newborn piglets, no IAV genetic material was found. No viral RNA was detected in samples of blood taken from gilts and piglets, placentas, lungs and tracheas taken from piglets euthanized after delivery. The significant decrease in the number and percentage of lymphocytes without leukopenia was observed at 4 dpi in inoculated gilts. The percentage of granulocytes increased significantly at 4 dpi in inoculated pigs. The concentration of IL-6, IL-10 and TNF-α were higher in inoculated gilts, while IL-4 and IFN-γ were not detected in the serum of any of animals. The serum concentrations of C-reactive protein remained stable during study, while haptoglobin concentrations increased significantly after inoculation. The results of the study indicate that infection of pregnant gilts with swine H1N2 IAV in the second month of pregnancy does not cause abortion and other reproduction disorders. No evidence for transplacental transmission of swine H1N2 IAV was found. However, due to subclinical course of influenza in the present experiment caution should be taken in extrapolating

  18. Design and performance of the CDC real-time reverse transcriptase PCR swine flu panel for detection of 2009 A (H1N1) pandemic influenza virus.

    Science.gov (United States)

    Shu, Bo; Wu, Kai-Hui; Emery, Shannon; Villanueva, Julie; Johnson, Roy; Guthrie, Erica; Berman, LaShondra; Warnes, Christine; Barnes, Nathelia; Klimov, Alexander; Lindstrom, Stephen

    2011-07-01

    Swine influenza viruses (SIV) have been shown to sporadically infect humans and are infrequently identified by the Influenza Division of the Centers for Disease Control and Prevention (CDC) after being received as unsubtypeable influenza A virus samples. Real-time reverse transcriptase PCR (rRT-PCR) procedures for detection and characterization of North American lineage (N. Am) SIV were developed and implemented at CDC for rapid identification of specimens from cases of suspected infections with SIV. These procedures were utilized in April 2009 for detection of human cases of 2009 A (H1N1) pandemic (pdm) influenza virus infection. Based on genetic sequence data derived from the first two viruses investigated, the previously developed rRT-PCR procedures were optimized to create the CDC rRT-PCR Swine Flu Panel for detection of the 2009 A (H1N1) pdm influenza virus. The analytical sensitivity of the CDC rRT-PCR Swine Flu Panel was shown to be 5 copies of RNA per reaction and 10(-1.3 - -0.7) 50% infectious doses (ID(50)) per reaction for cultured viruses. Cross-reactivity was not observed when testing human clinical specimens or cultured viruses that were positive for human seasonal A (H1N1, H3N2) and B influenza viruses. The CDC rRT-PCR Swine Flu Panel was distributed to public health laboratories in the United States and internationally from April 2009 until June 2010. The CDC rRT-PCR Swine Flu Panel served as an effective tool for timely and specific detection of 2009 A (H1N1) pdm influenza viruses and facilitated subsequent public health response implementation.

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

    Science.gov (United States)

    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

  20. Fever versus Fever: the role of host and vector susceptibility and interspecific competition in shaping the current and future distributions of the sylvatic cycles of dengue virus and yellow fever virus

    Science.gov (United States)

    Hanley, Kathryn A.; Monath, Thomas P.; Weaver, Scott C.; Rossi, Shannan L.; Richman, Rebecca L.; Vasilakis, Nikos

    2013-01-01

    Two different species of flaviviruses, dengue virus (DENV) and yellow fever virus (YFV), that originated in sylvatic cycles maintained in non-human primates and forest-dwelling mosquitoes have emerged repeatedly into sustained human-to-human transmission by Aedes aegypti mosquitoes. Sylvatic cycles of both viruses remain active, and where the two viruses overlap in West Africa they utilize similar suites of monkeys and Aedes mosquitoes. These extensive similarities render the differences in the biogeography and epidemiology of the two viruses all the more striking. First, the sylvatic cycle of YFV originated in Africa and was introduced into the New World, probably as a result of the slave trade, but is absent in Asia; in contrast, sylvatic DENV likely originated in Asia and has spread to Africa but not to the New World. Second, while sylvatic YFV can emerge into extensive urban outbreaks in humans, these invariably die out, whereas four different types of DENV have established human transmission cycles that are ecologically and evolutionarily distinct from their sylvatic ancestors. Finally, transmission of YFV among humans has been documented only in Africa and the Americas, whereas DENV is transmitted among humans across most of the range of competent Aedes vectors, which in the last decade has included every continent save Antarctica. This review summarizes current understanding of sylvatic transmission cycles of YFV and DENV, considers possible explanations for their disjunct distributions, and speculates on the potential consequences of future establishment of a sylvatic cycle of DENV in the Americas. PMID:23523817

  1. Attenuation of pathogenic Rift Valley fever virus strain through the chimeric S-segment encoding sandfly fever phlebovirus NSs or a dominant-negative PKR.

    Science.gov (United States)

    Nishiyama, Shoko; Slack, Olga A L; Lokugamage, Nandadeva; Hill, Terence E; Juelich, Terry L; Zhang, Lihong; Smith, Jennifer K; Perez, David; Gong, Bin; Freiberg, Alexander N; Ikegami, Tetsuro

    2016-11-16

    Rift Valley fever is a mosquito-borne zoonotic disease affecting ruminants and humans. Rift Valley fever virus (RVFV: family Bunyaviridae, genus Phlebovirus) causes abortions and fetal malformations in ruminants, and hemorrhagic fever, encephalitis, or retinitis in humans. The live-attenuated MP-12 vaccine is conditionally licensed for veterinary use in the US. However, this vaccine lacks a marker for the differentiation of vaccinated from infected animals (DIVA). NSs gene is dispensable for RVFV replication, and thus, rMP-12 strains lacking NSs gene is applicable to monitor vaccinated animals. However, the immunogenicity of MP-12 lacking NSs was not as high as parental MP-12. Thus, chimeric MP-12 strains encoding NSs from either Toscana virus (TOSV), sandfly fever Sicilian virus (SFSV) or Punta Toro virus Adames strain (PTA) were characterized previously. Although chimeric MP-12 strains are highly immunogenic, the attenuation through the S-segment remains unknown. Using pathogenic ZH501 strain, we aimed to demonstrate the attenuation of ZH501 strain through chimeric S-segment encoding either the NSs of TOSV, SFSV, PTA, or Punta Toro virus Balliet strain (PTB). In addition, we characterized rZH501 encoding a human dominant-negative PKR (PKRΔE7), which also enhances the immunogenicity of MP-12. Study done on mice revealed that attenuation of rZH501 occurred through the S-segment encoding either PKRΔE7 or SFSV NSs. However, rZH501 encoding either TOSV, PTA, or PTB NSs in the S-segment uniformly caused lethal encephalitis. Our results indicated that the S-segments encoding PKRΔE7 or SFSV NSs are attenuated and thus applicable toward next generation MP-12 vaccine candidates that encode a DIVA marker.

  2. Evidence of reassortment of pandemic H1N1 influenza virus in swine in Argentina: are we facing the expansion of potential epicenters of influenza emergence?

    Science.gov (United States)

    Pereda, Ariel; Rimondi, Agustina; Cappuccio, Javier; Sanguinetti, Ramon; Angel, Matthew; Ye, Jianqiang; Sutton, Troy; Dibárbora, Marina; Olivera, Valeria; Craig, Maria I.; Quiroga, Maria; Machuca, Mariana; Ferrero, Andrea; Perfumo, Carlos; Perez, Daniel R.

    2011-01-01

    Please cite this paper as: Pereda et al. (2011) Evidence of reassortment of pandemic H1N1 influenza virus in swine in Argentina: are we facing the expansion of potential epicenters of influenza emergence? Influenza and Other Respiratory Viruses 5(6), 409–412. In this report, we describe the occurrence of two novel swine influenza viruses (SIVs) in pigs in Argentina. These viruses are the result of two independent reassortment events between the H1N1 pandemic influenza virus (H1N1pdm) and human‐like SIVs, showing the constant evolution of influenza viruses at the human–swine interface and the potential health risk of H1N1pdm as it appears to be maintained in the swine population. It must be noted that because of the lack of information regarding the circulation of SIVs in South America, we cannot discard the possibility that ancestors of the H1N1pdm or other SIVs have been present in this part of the world. More importantly, these findings suggest an ever‐expanding geographic range of potential epicenters of influenza emergence with public health risks. PMID:21668680

  3. Short time window for transmissibility of African swine fever virus from a contaminated environment

    DEFF Research Database (Denmark)

    Olesen, A S; Lohse, L; Boklund, A.

    2018-01-01

    pens after 3, 5 or 7 days did not develop any signs of ASFV infection and no viral DNA was detected in blood samples obtained from these pigs within the following 3 weeks. Thus, it was shown that exposure of pigs to an environment contaminated with ASFV can result in infection. However, the time window...

  4. Gradual development of the interferon-γ response of swine to porcine reproductive and respiratory syndrome virus infection or vaccination

    International Nuclear Information System (INIS)

    Meier, William A.; Galeota, Judy; Osorio, Fernando A.; Husmann, Robert J.; Schnitzlein, William M.; Zuckermann, Federico A.

    2003-01-01

    Infection of swine with virulent porcine reproductive and respiratory syndrome (PRRS) virus induced a rapid, robust antibody response that comprised predominantly nonneutralizing antibodies and waned after approximately 3 months. In contrast, the initial onset of virus-specific interferon (IFN)-γ-secreting cells (SC) in the pig lymphocyte population remained at a fairly low level during this period and then increased gradually in frequency, plateauing at 6 months postinfection. A similar polarization of the host humoral and cellular immune responses was also observed in pigs immunized with a PRRS-modified live virus (MLV) vaccine. Even coadministration of an adjuvant that enhanced the immune response to a pseudorabies (PR) MLV vaccine failed to alter the induction of PRRS virus-specific IFN-γ SC (comprising predominately CD4/CD8α double positive memory T cells with a minority being typical CD4 - /CD8αβ + T cells) and the generation of neutralizing antibodies. Moreover, unlike inactivated PR virus, nonviable PRRS virus did not elicit virus-neutralizing antibody production. Presumably, an intrinsic property of this pathogen delays the development of the host IFN-γ response and preferentially stimulates the synthesis of antibodies incapable of neutralization

  5. A Novel System for Identification of Inhibitors of Rift Valley Fever Virus Replication

    OpenAIRE

    Piper, Mary E.; Gerrard, Sonja R.

    2010-01-01

    Rift Valley fever virus (RVFV) is a human and livestock pathogen endemic to sub-Saharan Africa. We have developed a T7-dependent system for the efficient production of RVFV-like particles (RVF-VLPs) based on the virulent ZH-501 strain of RVFV. The RVF-VLPs are capable of performing a single round of infection, allowing for the study of viral replication, assembly, and infectivity. We demonstrate that these RVF-VLPs are antigenically indistinguishable from authentic RVFV and respond similarly ...

  6. A Novel System for Identification of Inhibitors of Rift Valley Fever Virus Replication

    Directory of Open Access Journals (Sweden)

    Mary E. Piper

    2010-03-01

    Full Text Available Rift Valley fever virus (RVFV is a human and livestock pathogen endemic to sub-Saharan Africa. We have developed a T7-dependent system for the efficient production of RVFV-like particles (RVF-VLPs based on the virulent ZH-501 strain of RVFV. The RVF-VLPs are capable of performing a single round of infection, allowing for the study of viral replication, assembly, and infectivity. We demonstrate that these RVF-VLPs are antigenically indistinguishable from authentic RVFV and respond similarly to a wide array of known and previously unknown chemical inhibitors. This system should be useful for screening for small molecule inhibitors of RVFV replication.

  7. A novel system for identification of inhibitors of rift valley Fever virus replication.

    Science.gov (United States)

    Piper, Mary E; Gerrard, Sonja R

    2010-03-01

    Rift Valley fever virus (RVFV) is a human and livestock pathogen endemic to sub-Saharan Africa. We have developed a T7-dependent system for the efficient production of RVFV-like particles (RVF-VLPs) based on the virulent ZH-501 strain of RVFV. The RVF-VLPs are capable of performing a single round of infection, allowing for the study of viral replication, assembly, and infectivity. We demonstrate that these RVF-VLPs are antigenically indistinguishable from authentic RVFV and respond similarly to a wide array of known and previously unknown chemical inhibitors. This system should be useful for screening for small molecule inhibitors of RVFV replication.

  8. Isolation and whole-genome sequencing of a Crimean-Congo hemorrhagic fever virus strain, Greece.

    Science.gov (United States)

    Papa, Anna; Papadopoulou, Elpida; Tsioka, Katerina; Kontana, Anastasia; Pappa, Styliani; Melidou, Ageliki; Giadinis, Nektarios D

    2018-03-01

    Crimean-Congo hemorrhagic fever virus (CCHFV) was isolated from a pool of two adult Rhipicephalus bursa ticks removed from a goat in 2015 in Greece. The strain clusters into lineage Europe 2 representing the second available whole-genome sequenced isolate of this lineage. CCHFV IgG antibodies were detected in 8 of 19 goats of the farm. Currently CCHFV is not associated with disease in mammals other than humans. Studies in animal models are needed to investigate the pathogenicity level of lineage Europe 2 and compare it with that of other lineages. Copyright © 2018 Elsevier GmbH. All rights reserved.

  9. Calcium Regulation of Hemorrhagic Fever Virus Budding: Mechanistic Implications for Host-Oriented Therapeutic Intervention.

    Directory of Open Access Journals (Sweden)

    Ziying Han

    2015-10-01

    Full Text Available Hemorrhagic fever viruses, including the filoviruses (Ebola and Marburg and arenaviruses (Lassa and Junín viruses, are serious human pathogens for which there are currently no FDA approved therapeutics or vaccines. Importantly, transmission of these viruses, and specifically late steps of budding, critically depend upon host cell machinery. Consequently, strategies which target these mechanisms represent potential targets for broad spectrum host oriented therapeutics. An important cellular signal implicated previously in EBOV budding is calcium. Indeed, host cell calcium signals are increasingly being recognized to play a role in steps of entry, replication, and transmission for a range of viruses, but if and how filoviruses and arenaviruses mobilize calcium and the precise stage of virus transmission regulated by calcium have not been defined. Here we demonstrate that expression of matrix proteins from both filoviruses and arenaviruses triggers an increase in host cytoplasmic Ca2+ concentration by a mechanism that requires host Orai1 channels. Furthermore, we demonstrate that Orai1 regulates both VLP and infectious filovirus and arenavirus production and spread. Notably, suppression of the protein that triggers Orai activation (Stromal Interaction Molecule 1, STIM1 and genetic inactivation or pharmacological blockade of Orai1 channels inhibits VLP and infectious virus egress. These findings are highly significant as they expand our understanding of host mechanisms that may broadly control enveloped RNA virus budding, and they establish Orai and STIM1 as novel targets for broad-spectrum host-oriented therapeutics to combat these emerging BSL-4 pathogens and potentially other enveloped RNA viruses that bud via similar mechanisms.

  10. Studies on the pathogenesis of fever with influenzal viruses. II. The effects of endogenous pyrogen in normal and virus-tolerant recipients.

    Science.gov (United States)

    ATKINS, E; HUANG, W C

    1958-03-01

    Observations have been made on the fever-inducing properties of an endogenous pyrogen found in the circulation of rabbits after the intravenous inoculation of Newcastle disease virus (NDV). When endogenous pyrogen was given to a normal recipient, a biphasic fever was produced which simulated that seen with bacterial endotoxins. With the use of a technique of serial passive transfer, it has been shown that the "double-humped" response results from two separate actions of the injected pyrogen. The first of these appears to be a direct stimulation of the thermoregulatory centers. The second involves the release of further endogenous pyrogen in the normal recipient to cause, in turn, the second fever peak. Since the injection of endogenous pyrogen did not produce a significant change in the number of circulating leukocytes, it is inferred that this substance is different from either bacterial or tissue polysaccharides. In rabbits rendered tolerant by a previous injection of virus the second fever peak failed to appear and the response to endogenous pyrogen was monophasic. Evidence indicates that the absence of a second fever peak in the tolerant recipient was not due to rise in temperature on the preceding day of virus injection or to the development of either serum inhibitors or tolerance to virus itself. It is postulated that prior mobilization of endogenous pyrogen by virus may have modified the ability of the tolerant recipient to liberate further amounts of this substance in response to an injection of endogenous pyrogen.

  11. Characterization of Three Novel Linear Neutralizing B-Cell Epitopes in the Capsid Protein of Swine Hepatitis E Virus.

    Science.gov (United States)

    Chen, Yiyang; Liu, Baoyuan; Sun, Yani; Li, Huixia; Du, Taofeng; Nan, Yuchen; Hiscox, Julian A; Zhou, En-Min; Zhao, Qin

    2018-04-18

    Hepatitis E virus (HEV) causes liver disease in humans and is thought to be a zoonotic infection with domestic animals being a reservoir including swine and rabbits. One of the proteins encoded by the virus is the capsid protein. This is likely the major immune-dominant protein and a target for vaccination. Four monoclonal antibodies (MAbs); three novel; 1E4, 2C7, 2G9, and one previously characterized (1B5), were evaluated for binding to the capsid protein from genotype 4 (swine) hepatitis E virus (HEV). The results indicated that 625 DFCP 628 , 458 PSRPF 462 , and 407 EPTV 410 peptides on the capsid protein comprised minimal amino acid sequence motifs recognized by 1E4, 2C7, and 2G9, respectively. The data suggested that 2C7 and 2G9 epitopes were partially exposed on the surface of the capsid protein. Truncated genotype 4 swine HEV capsid protein (sp239, amino acids 368-606), can exist in multimeric forms. Pre-incubation of swine HEV with 2C7, 2G9, or 1B5 before addition to HepG2 cells partially blocked sp239 cell binding and inhibited swine HEV infection. The study indicated that 2C7, 2G9, and 1B5 partially blocked swine HEV infection of rabbits better than 1E4 or normal mouse IgG. The cross reactivity of antibodies suggested that capsid epitopes recognized by 2C7 and 2G9 are common to HEV strains infecting most host species. Collectively, MAbs 2C7, 2G9, and 1B5 were shown to recognize three novel linear neutralizing B-cell epitopes of genotype 4 HEV capsid protein. These results enhance understanding of HEV capsid protein structure to guide vaccine and anti-viral design. IMPORTANCE Genotype 3 and 4 HEVs are zoonotic viruses. Here, genotype 4 HEV was studied due to its prevalence in human populations and pig herds in China. To improve HEV disease diagnosis and prevention, a better understanding of antigenic structure and neutralizing epitopes of HEV capsid protein are needed. In this study, the locations of three novel linear B-cell recognition epitopes within

  12. Finding a new drug and vaccine for emerging swine flu: What is the concept?

    Directory of Open Access Journals (Sweden)

    Viroj Wiwanitkit

    2009-08-01

    Full Text Available Viroj WiwanitkitWiwanitkit House, Bangkhae, Bangkok 10160Abstract: Influenza is a well known infection of the respiratory system. The main clinical manifestations of influenza include fever, sore throat, headache, cough, coryza, and malaise. Apart from the well known classical influenza, there are also groups of influenza virus infections that are called “atypical infection”. These infections are usually due to a novel influenza virus infection. In early 2009, an emerging novel influenza originating from Mexico called swine flu was reported. The World Health Organization noted a level VI precaution, the highest level precaution possible, for this newest influenza virus infection. As of June 2009, it is not known if this disease will be successfully controlled. Finding new drugs and vaccine for the emerging swine flu is still required to cope with this emerging worldwide problem.Keywords: swine flu, drug, vaccine, concept

  13. Burden of pediatric influenza A virus infection post swine-flu H1N1 pandemic in Egypt.

    Science.gov (United States)

    Khattab, Adel; Shaheen, Malak; Kamel, Terez; El Faramay, Amel; El Rahman, Safaa Abd; Nabil, Dalia; Gouda, Mohamed

    2013-09-01

    To screen children with influenza like illness or with symptoms of acute respiratory tract infections for influenza A virus infection - post swine flu pandemic era - using rapid influenza diagnostic tests. During two years (2010 & 2011), 1 200 children with influenza like illness or acute respiratory tract infections (according to World Health Organization criteria) were recruited. Their ages ranged from 2-60 months. Nasopharyngeal aspirates specimens were collected from all children for rapid influenza A diagnostic test. Influenza A virus rapid test was positive in 47.5% of the children; the majority (89.6%) were presented with lower respiratory tract infections. Respiratory rate and temperature were significantly higher among positive rapid influenza test patients. Influenza A virus infection is still a major cause of respiratory tract infections in Egyptian children. It should be considered in all cases with cough and febrile episodes and influenza like symptoms even post swine flu pandemic. Copyright © 2013 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  14. Prevalence and titers of yellow fever virus neutralizing antibodies in previously vaccinated adults.

    Science.gov (United States)

    Miyaji, Karina Takesaki; Avelino-Silva, Vivian Iida; Simões, Marisol; Freire, Marcos da Silva; Medeiros, Carlos Roberto de; Braga, Patrícia Emilia; Neves, Maria Angélica Acalá; Lopes, Marta Heloisa; Kallas, Esper Georges; Sartori, Ana Marli Christovam

    2017-04-03

    The World Health Organization (WHO) recommends one single dose of the Yellow Fever (YF) vaccine based on studies of antibody persistency in healthy adults. We assessed the prevalence and titers of YF virus neutralizing antibodies in previously vaccinated persons aged  60 years, in comparison to younger adults. We also evaluated the correlation between antibody titers and the time since vaccination among participants who received one vaccine dose, and the seropositivity among participants vaccinated prior to or within the past 10 years. previously vaccinated healthy persons aged  18 years were included. YF virus neutralizing antibody titers were determined by means of the 50% Plaque Reduction Neutralization Test. 46 persons aged  60 years and 48 persons aged 18 to 59 years were enrolled. There was no significant difference in the prevalence of YF virus neutralizing antibodies between the two groups (p = 0.263). However, titers were significantly lower in the elderly (p = 0.022). There was no correlation between YF virus neutralizing antibody titers and the time since vaccination. There was no significant difference in seropositivity among participants vaccinated prior to or within the past 10 years. the clinical relevance of the observed difference in YF virus neutralizing antibody titers between the two groups is not clear.

  15. Molecular detection of hepatitis E virus in feces and slurry from swine farms, Rio Grande do Sul, Southern Brazil

    Directory of Open Access Journals (Sweden)

    J. Vasconcelos

    2015-06-01

    Full Text Available Hepatitis E virus (HEV is highly disseminated among swine herds worldwide. HEV is also a threat to public health, since particularly genotypes 3 and 4 may cause acute hepatitis in human beings. No previous studies were done on the occurrence of HEV in environmental samples in Rio Grande do Sul, Brazil. In the present study, reverse transcriptase-polymerase chain reaction (RT-PCR was employed to detect the presence of HEV in swine feces and in effluents from slurry lagoons in farms located in the municipality of Teutônia, inside the area of swine husbandry in the state. Pooled fecal samples from the floor of pig barns from 9 wean-to-finish farms and liquid manure samples were collected from the slurry lagoons from 8 of these farms. From the pooled fecal samples, 8/9 were positive for the HEV ORF1 gene by RT-PCR; all the slurry lagoon samples were positive for HEV RNA (100%. The identity of the HEV ORF1 amplicons was confirmed by sequencing belonging to HEV genotype 3, which was previously shown to be circulating in South America.

  16. Hepatitis E virus infection in central China reveals no evidence of cross-species transmission between human and swine in this area.

    Directory of Open Access Journals (Sweden)

    Wen Zhang

    Full Text Available Hepatitis E virus (HEV is a zoonotic pathogen of which several species of animal were reported as reservoirs. Swine stands out as the major reservoir for HEV infection in humans, as suggested by the close genetic relationship of swine and human virus. Since 2000, Genotype 4 HEV has become the dominant cause of hepatitis E disease in China. Recent reports showed that genotype 4 HEV is freely transmitted between humans and swine in eastern and southern China. However, the infection status of HEV in human and swine populations in central China is still unclear. This study was conducted in a rural area of central China, where there are many commercial swine farms. A total of 1476 serum and 554 fecal specimens were collected from the general human and swine populations in this area, respectively. The seroepidemiological study was conducted by enzyme-linked immunosorbent assay. Conserved genomic sequences of open reading frame 2 were detected using reverse transcription-PCR. The results indicated that the overall viral burden of the general human subjects was 0.95% (14/1476, while 7.0% (39/554 of the swine excreted HEV in stool. The positive rate of anti-HEV IgG and IgM in the serum samples was 7.9% (117/1476 and 1.6% (24/1476, respectively. Phylogenetic analysis based on the 150 nt partial sequence of the capsid protein gene showed that the 53 swine and human HEV isolates in the current study all belonged to genotype 4, clustering into three major groups. However, the HEV isolates prevalent in the human and swine populations were classified into known distinct subgenotypes, which suggested that no cross-species transmission between swine and humans had taken place in this area. This result was confirmed by cloning and phylogenetic analysis of the complete capsid protein gene sequence of three representative HEV strains in the three major groups. The cross reactivity between anti-HEV IgG from human sera and the two representative strains from swine in

  17. Serologic evidence of exposure to Rift Valley fever virus detected in Tunisia

    Directory of Open Access Journals (Sweden)

    A. Bosworth

    2016-01-01

    Full Text Available Rift Valley fever virus (RVFv is capable of causing dramatic outbreaks amongst economically important animal species and is capable of causing severe symptoms and mortality in humans. RVFv is known to circulate widely throughout East Africa; serologic evidence of exposure has also been found in some northern African countries, including Mauritania. This study aimed to ascertain whether RVFv is circulating in regions beyond its known geographic range. Samples from febrile patients (n=181 and nonfebrile healthy agricultural and slaughterhouse workers (n=38 were collected during the summer of 2014 and surveyed for exposure to RVFv by both serologic tests and PCR. Of the 219 samples tested, 7.8% of nonfebrile participants showed immunoglobulin G reactivity to RVFv nucleoprotein and 8.3% of febrile patients showed immunoglobulin M reactivity, with the latter samples indicating recent exposure to the virus. Our results suggest an active circulation of RVFv and evidence of human exposure in the population of Tunisia.

  18. Mild Clinical Course of Severe Fever with Thrombocytopenia Syndrome Virus Infection in an Elderly Japanese Patient

    Directory of Open Access Journals (Sweden)

    Yuko Ohagi

    2014-01-01

    Full Text Available Severe fever with thrombocytopenia syndrome (SFTS is an emerging infectious and hemorrhagic disease recently described in China and western Japan. A 71-year-old healthy Japanese woman noticed a tick biting her after harvesting in an orchard and removed it herself. She developed diarrhea, anorexia, and chills eight days later. Because these symptoms continued, she visited a primary care physician 6 days after the onset. Laboratory data revealed thrombocytopenia, leukocytopenia, and elevated liver enzymes. She was then referred to our hospital. Although not completely fulfilling the diagnostic criteria used in a retrospective study in Japan, SFTS was suspected, and we detected SFTS virus in the patient’s blood using RT-PCR. However, she recovered without intensive treatment and severe complications 13 days after the onset. In this report, we present a mild clinical course of SFTS virus infection in Japan in detail.

  19. Biosafety standards for working with Crimean-Congo hemorrhagic fever virus.

    Science.gov (United States)

    Weidmann, Manfred; Avsic-Zupanc, Tatjana; Bino, Silvia; Bouloy, Michelle; Burt, Felicity; Chinikar, Sadegh; Christova, Iva; Dedushaj, Isuf; El-Sanousi, Ahmed; Elaldi, Nazif; Hewson, Roger; Hufert, Frank T; Humolli, Isme; Jansen van Vuren, Petrus; Koçak Tufan, Zeliha; Korukluoglu, Gülay; Lyssen, Pieter; Mirazimi, Ali; Neyts, Johan; Niedrig, Matthias; Ozkul, Aykut; Papa, Anna; Paweska, Janusz; Sall, Amadou A; Schmaljohn, Connie S; Swanepoel, Robert; Uyar, Yavuz; Weber, Friedemann; Zeller, Herve

    2016-11-01

    In countries from which Crimean-Congo haemorrhagic fever (CCHF) is absent, the causative virus, CCHF virus (CCHFV), is classified as a hazard group 4 agent and handled in containment level (CL)-4. In contrast, most endemic countries out of necessity have had to perform diagnostic tests under biosafety level (BSL)-2 or -3 conditions. In particular, Turkey and several of the Balkan countries have safely processed more than 100 000 samples over many years in BSL-2 laboratories. It is therefore advocated that biosafety requirements for CCHF diagnostic procedures should be revised, to allow the tests required to be performed under enhanced BSL-2 conditions with appropriate biosafety laboratory equipment and personal protective equipment used according to standardized protocols in the countries affected. Downgrading of CCHFV research work from CL-4, BSL-4 to CL-3, BSL-3 should also be considered.

  20. [Birds, mosquitoes and West Nile virus: little risk of West Nile fever in the Netherlands].

    Science.gov (United States)

    Duijster, Janneke W; Stroo, C J Arjan; Braks, Marieta A H

    2016-01-01

    Due to increased incidence of West Nile fever (WNF) in Europe and the rapid spread of West Nile virus (WNV) in the US, it is commonly thought that it will only be a matter of time before WNV reaches the Netherlands. However, assessing whether WNV is really a threat to the Dutch population is challenging, due to the numerous factors affecting transmission of the virus. Some of these factors are known to limit the risk of WNF in the Netherlands. This risk is determined by the interaction between the pathogen (WNV), the vectors (Culex mosquitoes), the reservoirs (birds) and the exposure of humans to infected mosquitoes. In this paper, we discuss the factors influencing introduction, establishment and spread of WNV in the Netherlands. The probability that each of these three phases will occur in the Netherlands is currently relatively small, as is the risk of WNF infection in humans in the Netherlands.

  1. A hamster model for Marburg virus infection accurately recapitulates Marburg hemorrhagic fever.

    Science.gov (United States)

    Marzi, Andrea; Banadyga, Logan; Haddock, Elaine; Thomas, Tina; Shen, Kui; Horne, Eva J; Scott, Dana P; Feldmann, Heinz; Ebihara, Hideki

    2016-12-15

    Marburg virus (MARV), a close relative of Ebola virus, is the causative agent of a severe human disease known as Marburg hemorrhagic fever (MHF). No licensed vaccine or therapeutic exists to treat MHF, and MARV is therefore classified as a Tier 1 select agent and a category A bioterrorism agent. In order to develop countermeasures against this severe disease, animal models that accurately recapitulate human disease are required. Here we describe the development of a novel, uniformly lethal Syrian golden hamster model of MHF using a hamster-adapted MARV variant Angola. Remarkably, this model displayed almost all of the clinical features of MHF seen in humans and non-human primates, including coagulation abnormalities, hemorrhagic manifestations, petechial rash, and a severely dysregulated immune response. This MHF hamster model represents a powerful tool for further dissecting MARV pathogenesis and accelerating the development of effective medical countermeasures against human MHF.

  2. Development of a membrane adsorber based capture step for the purification of yellow fever virus.

    Science.gov (United States)

    Pato, Tânia P; Souza, Marta Cristina O; Silva, Andréa N M R; Pereira, Renata C; Silva, Marlon V; Caride, Elena; Gaspar, Luciane P; Freire, Marcos S; Castilho, Leda R

    2014-05-19

    Yellow fever (YF) is an endemic disease in some tropical areas of South America and Africa that presents lethality rate between 20 and 50%. There is no specific treatment and to control this disease a highly effective live-attenuated egg based vaccine is widely used for travelers and residents of areas where YF is endemic. However, recent reports of rare, sometimes fatal, adverse events post-vaccination have raised concerns. In order to increase safety records, alternative strategies should be considered, such as developing a new inactivated vaccine using a cell culture based technology, capable of meeting the demands in cases of epidemic. With this goal, the production of YF virus in Vero cells grown on microcarriers and its subsequent purification by chromatographic techniques was studied. In this work we investigate the capture step of the purification process of the YF virus. At first, virus stability was studied over a wide pH range, showing best results for the alkaline region. Considering this result and the pI of the envelope protein previously determined in silico, a strong anion exchanger was considered most suitable. Due to the easy scalability, simplicity to handle, absence of diffusional limitations and suitability for virus handling of membrane adsorbers, a Q membrane was evaluated. The amount of antigen adsorbed onto the membrane was investigated within the pH range for virus stability, and the best pH for virus adsorption was considered to be 8.5. Finally, studies on gradient and step elution allowed to determine the most adequate salt concentration for washing (0.15M) and virus elution (0.30 M). Under these operating conditions, it was shown that this capture step is quite efficient, showing high product recovery (93.2±30.3%) and efficient DNA clearance (0.9±0.3 ng/dose). Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Antigenic variants of yellow fever virus with an altered neurovirulence phenotype in mice.

    Science.gov (United States)

    Ryman, K D; Xie, H; Ledger, T N; Campbell, G A; Barrett, A D

    1997-04-14

    The live-attenuated yellow fever (YF) vaccine virus, strain 17D-204, has long been known to consist of a heterologous population of virions. Gould et al. (J. Gen. Virol. 70, 1889-1894 (1989)) previously demonstrated that variant viruses exhibiting a YF wild-type-specific envelope (E) protein epitope are present at low frequency in the vaccine pool and were able to isolate representative virus variants with and without this epitope, designated 17D(+wt) and 17D(-wt), respectively. These variants were employed here in an investigation of YF virus pathogenesis in the mouse model. Both the 17D-204 parent and the 17D(+wt) variant viruses were lethal for adult outbred mice by the intracerebral route of inoculation. However, the 17D(-wt) variant was significantly attenuated (18% mortality rate) and replicated to much lower titer in the brains of infected mice. A single amino acid substitution in the envelope (E) protein at E-240 (Ala-->Val) was identified as responsible for the restricted replication of the 17D(-wt) variant in vivo. The 17D(+wt) variant has an additional second-site mutation, believed to encode a reversion to the neurovirulence phenotype of the 17D-204 parent virus. The amino acid substitution in the E protein at E-173 (Thr-->Ile) of the 17D(+wt) variant which results in the appearance of the wild-type-specific epitope or nucleotide changes in the 5' and 3' noncoding regions of the virus are proposed as a candidates.

  4. Complete genome sequence of a novel influenza A H1N2 virus circulating in swine from Central Bajio region, Mexico.

    Science.gov (United States)

    Sánchez-Betancourt, J I; Cervantes-Torres, J B; Saavedra-Montañez, M; Segura-Velázquez, R A

    2017-12-01

    The aim of this study was to perform the complete genome sequence of a swine influenza A H1N2 virus strain isolated from a pig in Guanajuato, México (A/swine/Mexico/GtoDMZC01/2014) and to report its seroprevalence in 86 counties at the Central Bajio zone. To understand the evolutionary dynamics of the isolate, we undertook a phylogenetic analysis of the eight gene segments. These data revealed that the isolated virus is a reassortant H1N2 subtype, as its genes are derived from human (HA, NP, PA) and swine (M, NA, PB1, PB2 and NS) influenza viruses. Pig serum samples were analysed by the hemagglutination inhibition test, using wild H1N2 and H3N2 strains (A/swine/México/Mex51/2010 [H3N2]) as antigen sources. Positive samples to the H1N2 subtype were processed using the field-isolated H1N1 subtype (A/swine/México/Ver37/2010 [H1N1]). Seroprevalence to the H1N2 subtype was 26.74% in the sampled counties, being Jalisco the state with highest seroprevalence to this subtype (35.30%). The results herein reported demonstrate that this new, previously unregistered influenza virus subtype in México that shows internal genes from other swine viral subtypes isolated in the past 5 years, along with human virus-originated genes, is widely distributed in this area of the country. © 2017 Blackwell Verlag GmbH.

  5. Regional patterns of genetic diversity in swine influenza A viruses in the United States from 2010 to 2016.

    Science.gov (United States)

    Walia, Rasna R; Anderson, Tavis K; Vincent, Amy L

    2018-04-06

    Regular spatial and temporal analyses of the genetic diversity and evolutionary patterns of influenza A virus (IAV) in swine informs control efforts and improves animal health. Initiated in 2009, the USDA passively surveils IAV in U.S. swine, with a focus on subtyping clinical respiratory submissions, sequencing at minimum the hemagglutinin (HA) and neuraminidase (NA) genes, and sharing these data publicly. In this study, our goal was to quantify and describe regional and national patterns in the genetic diversity and evolution of IAV in U.S. swine from 2010 to 2016. A comprehensive phylogenetic and epidemiological analysis of publicly available HA and NA genes generated by the USDA surveillance system collected from January 2010 to December 2016 was conducted. The dominant subtypes and genetic clades detected during the study period were H1N1 (H1-γ/1A.3.3.3, N1-classical, 29%), H1N2 (H1-δ1/1B.2.2, N2-2002, 27%), and H3N2 (H3-IV-A, N2-2002, 15%), but many other minor clades were also maintained. Year-round circulation was observed, with a primary epidemic peak in October-November and a secondary epidemic peak in March-April. Partitioning these data into 5 spatial zones revealed that genetic diversity varied regionally and was not correlated with aggregated national patterns of HA/NA diversity. These data suggest that vaccine composition and control efforts should consider IAV diversity within swine production regions in addition to aggregated nat