WorldWideScience

Sample records for african swine fever virus

  1. 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 Europe

  2. The trans Golgi Network Is Lost from Cells Infected with African Swine Fever Virus

    OpenAIRE

    McCrossan, Mari; Windsor, Miriam; Ponnambalam, Sreenivasan; Armstrong, John; Wileman, Thomas

    2001-01-01

    The cellular secretory pathway is important during the assembly and envelopment of viruses and also controls the transport of host proteins, such as cytokines and major histocompatibility proteins, that function during the elimination of viruses by the immune system. African swine fever virus (ASFV) encodes at least 26 proteins with stretches of hydrophobic amino acids suggesting entry into the secretory pathway (R. J. Yanez, J. M. Rodriguez, M. L. Nogal, L. Yuste, C. Enriquez, J. F. Rodrigue...

  3. DNA Vaccination Partially Protects against African Swine Fever Virus Lethal Challenge in the Absence of Antibodies

    OpenAIRE

    Jordi M Argilaguet; Pérez Martín, Eva; Nofrarías Espadamala, Miquel; Gallardo, Carmina; Accensi Alemany, Francesc; Lacasta, Anna; Mora Salvatierra, Mercedes; Ballester Devis, Maria; Galindo Cardiel, Iván; López Soria, Sergio; José M Escribano; Reche, Pedro A.; Rodríguez, Fernando

    2012-01-01

    The lack of available vaccines against African swine fever virus (ASFV) means that the evaluation of new immunization strategies is required. Here we show that fusion of the extracellular domain of the ASFV Hemagglutinin (sHA) to p54 and p30, two immunodominant structural viral antigens, exponentially improved both the humoral and the cellular responses induced in pigs after DNA immunization. However, immunization with the resulting plasmid (pCMV-sHAPQ) did not confer protection against letha...

  4. Functional characterization and inhibition of the type II DNA topoisomerase coded by African swine fever virus.

    Science.gov (United States)

    Coelho, João; Ferreira, Fernando; Martins, Carlos; Leitão, Alexandre

    2016-06-01

    DNA topoisomerases are essential for DNA metabolism and while their role is well studied in prokaryotes and eukaryotes, it is less known for virally-encoded topoisomerases. African swine fever virus (ASFV) is a nucleo-cytoplasmic large DNA virus that infects Ornithodoros ticks and all members of the family Suidae, representing a global threat for pig husbandry with no effective vaccine nor treatment. It was recently demonstrated that ASFV codes for a type II topoisomerase, highlighting a possible target for control of the virus. In this work, the ASFV DNA topoisomerase II was expressed in Saccharomyces cerevisiae and found to efficiently decatenate kDNA and to processively relax supercoiled DNA. Optimal conditions for its activity were determined and its sensitivity to a panel of topoisomerase poisons and inhibitors was evaluated. Overall, our results provide new knowledge on viral topoisomerases and on ASFV, as well as a possible target for the control of this virus. PMID:27060564

  5. Antibody-mediated neutralization of African swine fever virus: myths and facts.

    Science.gov (United States)

    Escribano, José M; Galindo, Inmaculada; Alonso, Covadonga

    2013-04-01

    Almost all viruses can be neutralized by antibodies. However, there is some controversy about antibody-mediated neutralization of African swine fever virus (ASFV) with sera from convalescent pigs and about the protective relevance of antibodies in experimentally vaccinated pigs. At present, there is no vaccine available for this highly lethal and economically relevant virus and all classical attempts to generate a vaccine have been unsuccessful. This failure has been attributed, in part, to what many authors describe as the absence of neutralizing antibodies. The findings of some studies clearly contradict the paradigm of the impossibility to neutralize ASFV by means of monoclonal or polyclonal antibodies. This review discusses scientific evidence of these types of antibodies in convalescent and experimentally immunized animals, the nature of their specificity, the neutralization-mediated mechanisms demonstrated, and the potential relevance of antibodies in protection. PMID:23159730

  6. Experimental infection of warthos (Phacochoerus aethiopicus) with African swine fever virus.

    Science.gov (United States)

    Thomson, G R; Gainaru, M D; Van Dellen, A F

    1980-03-01

    Although there were no obvious signs of illness following experimental infection of young warthog with African swine fever virus, the animals developed viraemias between 10(2,4) and 10(3,6) HD50/ml within the first week of infection, and virus concentrations in a number of lymphatic tissues attained high levels (greater than or equal to 10(6) HD50/g). Unlike in blood, and to some extent in the spleen, virus titres in lymph nodes did not decline appreciable during the 33-day observation period, since at the end of the period lymphatic tissues from 2 warthog were still infectious for domestic pigs to which these tissues were fed. PMID:7454231

  7. African swine fever virus AP endonuclease is a redox-sensitive enzyme that repairs alkylating and oxidative damage to DNA

    OpenAIRE

    Redrejo-Rodríguez, Modesto; Alexander A Ishchenko; Saparbaev, Murat K.; Salas, María L.; Salas, José

    2009-01-01

    African swine fever virus (ASFV) encodes an AP endonuclease (pE296R) which is essential for virus growth in swine macrophages. We show here that the DNA repair functions of pE296R (AP endonucleolytic, 3′ → 5′ exonuclease, 3′-diesterase and nucleotide incision repair (NIR) activities) and DNA binding are inhibited by reducing agents. Protein pE296R contains one intramolecular disulfide bond, whose disruption by reducing agents might perturb the interaction of the viral AP endonuclease with the...

  8. Diagnosis and genotyping of African swine fever viruses from 2015 outbreaks in Zambia.

    Science.gov (United States)

    Thoromo, Jonas; Simulundu, Edgar; Chambaro, Herman M; Mataa, Liywalii; Lubaba, Caesar H; Pandey, Girja S; Takada, Ayato; Misinzo, Gerald; Mweene, Aaron S

    2016-01-01

    In early 2015, a highly fatal haemorrhagic disease of domestic pigs resembling African swine fever (ASF) occurred in North Western, Copperbelt, and Lusaka provinces of Zambia. Molecular diagnosis by polymerase chain reaction targeting specific amplification of p72 (B646L) gene of ASF virus (ASFV) was conducted. Fourteen out of 16 domestic pigs from the affected provinces were found to be positive for ASFV. Phylogenetic analyses based on part of the p72 and the complete p54 (E183L) genes revealed that all the ASFVs detected belonged to genotypes I and Id, respectively. Additionally, epidemiological data suggest that the same ASFV spread from Lusaka to other provinces possibly through uncontrolled and/or illegal pig movements. Although the origin of the ASFV that caused outbreaks in domestic pigs in Zambia could not be ascertained, it appears likely that the virus may have emerged from within the country or region, probably from a sylvatic cycle. It is recommended that surveillance of ASF, strict biosecurity, and quarantine measures be imposed in order to prevent further spread and emergence of new ASF outbreaks in Zambia. PMID:27247062

  9. 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...

  10. Classical Swine Fever Virus-Rluc Replicons

    DEFF Research Database (Denmark)

    Risager, Peter Christian; Belsham, Graham J.; Rasmussen, Thomas Bruun

    Classical swine fever virus (CSFV) is the etiologic agent of the severe porcine disease, classical swine fever. Unraveling the molecular determinants of efficient replication is crucial for gaining proper knowledge of the pathogenic traits of this virus. Monitoring the replication competence within...

  11. African swine fever virus serodiagnosis: a general review with a focus on the analyses of African serum samples.

    Science.gov (United States)

    Cubillos, Carolina; Gómez-Sebastian, Silvia; Moreno, Noelia; Nuñez, María C; Mulumba-Mfumu, Leopold K; Quembo, Carlos J; Heath, Livio; Etter, Eric M C; Jori, Ferran; Escribano, Jose M; Blanco, Esther

    2013-04-01

    African swine fever (ASF) is an infectious disease that causes heavy mortality in domestic pigs. At present there is no vaccine against ASF, and eradication in countries where the disease is endemic is based only on competent diagnosis programs and the sacrifice of infected animals. Due to the presence of natural attenuated strains, certain infection conditions may result in reduced mortality. In these situations, the disease can be diagnosed by detection of specific antibodies. The use of classical and validated diagnosis assays, such as ELISA and Indirect Immunofluorescence or Immunoblotting, allowed the eradication of ASF in the Iberian Peninsula in the 1990s. However, given that conventional tests include the use of antigens obtained from ASF virus (ASFV)-infected cells, they have several disadvantages, such as difficulties to achieve standardization and also the risks associated with the manipulation of live virus. Such drawbacks have led to the development of alternative and more robust systems for the production of ASFV antigens for use in anti-ASFV antibody detection systems. In the present review, we provide an update on current knowledge about antigen targets for ASFV serodiagnosis, the significant progress made in recombinant antigen production, and the refinement of ASF serological diagnostic assays. Moreover, we describe the accuracy of an ELISA developed for the serodiagnosis of ASFV in Africa. This assay is based on a novel p30 recombinant protein (p30r) obtained from an Eastern African viral isolate (Morara strain), which shares 100% amino acid sequence identity with the Georgia virus isolate. That study included the analyses of 587 field sera collected from domestic pigs and warthogs in Senegal (West Africa), the Democratic Republic of Congo (Central Africa), Mozambique (South-East Africa), and South Africa. The results revealed that the novel p30r-based ELISA allows the accurate detection of antibodies against ASFV, independently of the

  12. 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)

    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

  13. The pathogenesis of highly virulent African Swine Fever virus in domestic pigs exposed via intraoropharyngeal, intranasopharyngeal, and intramuscular inoculation, and by direct contact with infected pigs

    Science.gov (United States)

    In order to optimize novel systems for African Swine Fever Virus (ASFV) vaccine development, domestic pigs were challenged with the highly virulent ASFV-Malawi strain via intraoropharyngeal (IOP), intranasopharyngeal (INP), intramuscular (IM), and direct contact (DC) routes. Direct challenge doses ...

  14. 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.

  15. Drivers and risk factors for circulating African swine fever virus in Uganda, 2012-2013.

    Science.gov (United States)

    Kabuuka, T; Kasaija, P D; Mulindwa, H; Shittu, A; Bastos, A D S; Fasina, F O

    2014-10-01

    We explored observed risk factors and drivers of infection possibly associated with African swine fever (ASF) epidemiology in Uganda. Representative sub-populations of pig farms and statistics were used in a case-control model. Indiscriminate disposal of pig viscera and waste materials after slaughter, including on open refuse dumps, farm-gate buyers collecting pigs and pig products from within a farm, and retention of survivor pigs were plausible risk factors. Wire mesh-protected windows in pig houses were found to be protective against ASF infection. Sighting engorged ticks on pigs, the presence of a lock for each pig pen and/or a gate at the farm entrance were significantly associated with infection/non-infection; possible explanations were offered. Strict adherence to planned within-farm and community-based biosecurity, and avoidance of identified risk factors is recommended to reduce infection. Training for small-scale and emerging farmers should involve multidimensional and multidisciplinary approaches to reduce human-related risky behaviours driving infection. PMID:25066802

  16. 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.

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

    Science.gov (United States)

    Hernáez, Bruno; Guerra, Milagros; Salas, María L; Andrés, Germán

    2016-04-01

    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. PMID:27110717

  18. African swine fever virus infection of the bushpig (Potamochoerus porcus) and its significance in the epidemiology of the disease.

    Science.gov (United States)

    Anderson, E C; Hutchings, G H; Mukarati, N; Wilkinson, P J

    1998-04-30

    Warthog (Phacochoerus aethiopicus), giant forest hog (Hylochoerus meinertzhageni) and bushpig (Potamochoerus porcus) are known to be susceptible to infection with African swine fever (ASF) virus. Little however, is known about the ecology of the disease in the bushpig. This study has shown that the bushpig remains viraemic for between 35 and 91 days following infection during which time it is able to infect the tick vector O. moubata. These ticks were able to transmit the disease to pigs. The virus persists in the lymphatic tissues for less than 34 weeks. Bushpigs infected with LIL 20/l virus but not VIC T90/l virus transmitted infection to in-contact pigs. Infected domestic pigs did not transmit the infection to in-contact bushpigs. ASF virus was able to replicate in in vitro cultures of bushpig leucocytes and endothelial cells. Recovered bushpigs could be reinfected with some strains of virus but not others. While it has been demonstrated that bushpigs remain carriers of ASFV following infection a complete understanding of their significance in the epidemiology of the disease awaits further investigations of their association with O. moubata. PMID:9659687

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

    Science.gov (United States)

    Hernáez, Bruno; Guerra, Milagros; Salas, María L.

    2016-01-01

    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. PMID:27110717

  20. 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.

  1. Sensitivity of African swine fever virus to type I interferon is linked to genes within multigene families 360 and 505.

    Science.gov (United States)

    Golding, Josephine P; Goatley, Lynnette; Goodbourn, Steve; Dixon, Linda K; Taylor, Geraldine; Netherton, Christopher L

    2016-06-01

    African swine fever virus (ASFV) causes a lethal haemorrhagic disease of pigs. There are conflicting reports on the role of interferon in ASFV infection. We therefore analysed the interaction of ASFV with porcine interferon, in vivo and in vitro. Virulent ASFV induced biologically active IFN in the circulation of pigs from day 3-post infection, whereas low virulent OUR T88/3, which lacks genes from multigene family (MGF) 360 and MGF505, did not. Infection of porcine leucocytes enriched for dendritic cells, with ASFV, in vitro, induced high levels of interferon, suggesting a potential source of interferon in animals undergoing acute ASF. Replication of OUR T88/3, but not virulent viruses, was reduced in interferon pretreated macrophages and a recombinant virus lacking similar genes to those absent in OUR T88/3 was also inhibited. These findings suggest that as well as inhibiting the induction of interferon, MGF360 and MGF505 genes also enable ASFV to overcome the antiviral state. PMID:27043071

  2. Absence of Ornithodoros moubata, the vector of African swine fever virus, from the main pig producing area of Cameroon.

    Science.gov (United States)

    Ekue, N F; Wilkinson, P J

    1990-05-01

    No evidence for the presence of soft ticks of the Ornithodoros moubata complex was found during a survey of African swine fever carried out between 1985 and 1988 in the West Province and southern parts of the North West and South West Provinces of Cameroon. The survey consisted of interviews of veterinary assistants and farmers, distribution of a questionnaire and tick searches both manually and with carbon dioxide traps. The absence of warthogs (Phacochoerus aethiopicus) from these areas was also recorded. PMID:2371751

  3. African Swine Fever Epidemic, Poland, 2014–2015

    Science.gov (United States)

    Woźniakowski, Grzegorz; Kozak, Edyta; Niemczuk, Krzysztof; Frączyk, Magdalena; Bocian, Łukasz; Kowalczyk, Andrzej; Pejsak, Zygmunt

    2016-01-01

    In Poland, African swine fever (ASF) emerged in February 2014; by August 2015, the virus had been detected in >130 wild boar and in pigs in 3 backyard holdings. We evaluated ASF spread in Poland during these 18 months. Phylogenetic analysis indicated repeated incursions of genetically distinct ASF viruses of genotype II; the number of cases positively correlated wild boar density; and disease spread was very slow. More cases were reported during summer than autumn. The 18-month prevalence of ASF in areas under various animal movement restrictions was 18.6% among wild boar found dead or killed by vehicles and only 0.2% in hunted wild boar. Repeated introductions of the virus into the country, the primary role of wild boar in virus maintenance, and the slow spread of the disease indicate a need for enhanced biosecurity at pig holdings and continuous and intensive surveillance for fast detection of ASF. PMID:27314611

  4. Evaluation of possible mitigation measures to prevent introduction and spread of African swine fever virus through wild boar

    Directory of Open Access Journals (Sweden)

    European Food Safety Authority

    2014-03-01

    Full Text Available This scientific report has been prepared in response to a request for urgent scientific and technical assistance under Art 31 of Regulation (EC No 178/2002, in relation to possible mitigation measures to prevent introduction and spread of African swine fever virus (ASFV. It was requested to assess the feasibility to drastically reduce the wild boar population by hunting or by the use of traps, and to assess if prevention of movement of wild boars by feeding or by artificial physical barriers reduces the risk of spread of ASFV. No evidence was found in scientific literature proving that wild boar populations can be drastically reduced by hunting or trapping in Europe. The main reasons are the adaptive behaviour of wild boar, compensatory growth of the population and the possible influx of wild boar from adjacent areas. Thus, drastic hunting is not a tool to reduce the risk for introduction and spread of ASFV in wild boar populations. Furthermore, wild boar density thresholds for introduction, spread and persistence of ASFV in the wild boar populations are currently impossible to establish, due to the uncertainty regarding the extent of the spread and maintenance of ASFV, the biases in population datasets, the complex population structures and dynamics. Furthermore, attempts to drastically reduce wild boar populations may even increase transmission and facilitate progressive geographical spread of ASFV, since intensive hunting pressure on wild boar populations leads to dispersion of groups and individuals. Artificial feeding of wild boar might increase the risk of ASFV spread. Fencing can restrict wild boar movements, however further knowledge of the ASF epidemiology and spatial distribution of wild boar is required to identify the areas where fencing could be used as one possible element of a control programme and to assess the feasibility of its implementation.

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

    OpenAIRE

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

    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.

  6. Characterization of the atypical lymphocytes in African swine fever

    Science.gov (United States)

    Karalyan, Z. A.; Ter-Pogossyan, Z. R.; Abroyan, L. O.; Hakobyan, L. H.; Avetisyan, A. S.; Yu, Karalyan N.; Karalova, E. M.

    2016-01-01

    Aim: Atypical lymphocytes usually described as lymphocytes with altered shape, increased DNA amount, and larger size. For analysis of cause of genesis and source of atypical lymphocytes during African swine fever virus (ASFV) infection, bone marrow, peripheral blood, and in vitro model were investigated. Materials and Methods: Atypical lymphocytes under the influence of ASFV were studied for morphologic, cytophotometric, and membrane surface marker characteristics and were used in vivo and in vitro models. Results: This study indicated the increased size, high metabolic activity, and the presence of additional DNA amount in atypical lymphocytes caused by ASFV infection. Furthermore, in atypical lymphocytes, nuclear-cytoplasmic ratio usually decreased, compared to normal lymphocytes. In morphology, they looking like lymphocytes transformed into blasts by exposure to mitogens or antigens in vitro. They vary in morphologic detail, but most of them are CD2 positive. Conclusions: Our data suggest that atypical lymphocytes may represent an unusual and specific cellular response to ASFV infection. PMID:27536044

  7. Development and validation of a multiplex, real-time RT PCR assay for the simultaneous detection of classical and African swine fever viruses.

    Directory of Open Access Journals (Sweden)

    Felicity J Haines

    Full Text Available A single-step, multiplex, real-time polymerase chain reaction (RT-PCR was developed for the simultaneous and differential laboratory diagnosis of Classical swine fever virus (CSFV and African swine fever virus (ASFV alongside an exogenous internal control RNA (IC-RNA. Combining a single extraction methodology and primer and probe sets for detection of the three target nucleic acids CSFV, ASFV and IC-RNA, had no effect on the analytical sensitivity of the assay and the new triplex RT-PCR was comparable to standard PCR techniques for CSFV and ASFV diagnosis. After optimisation the assay had a detection limit of 5 CSFV genome copies and 22 ASFV genome copies. Analytical specificity of the triplex assay was validated using a panel of viruses representing 9 of the 11 CSFV subgenotypes, at least 8 of the 22 ASFV genotypes as well as non-CSFV pestiviruses. Positive and negative clinical samples from animals infected experimentally, due to field exposure or collected from the UK which is free from both swine diseases, were used to evaluate the diagnostic sensitivity and specificity for detection of both viruses. The diagnostic sensitivity was 100% for both viruses whilst diagnostic specificity estimates were 100% for CSFV detection and 97.3% for ASFV detection. The inclusion of a heterologous internal control allowed identification of false negative results, which occurred at a higher level than expected. The triplex assay described here offers a valuable new tool for the differential detection of the causative viruses of two clinically indistinguishable porcine diseases, whose geographical occurrence is increasingly overlapping.

  8. Patterns of gene expression in swine macrophages infected with classical swine fever virus detected by microarray

    Science.gov (United States)

    Classical Swine Fever (CSF) is a highly contagious disease of swine that is characterized by fever, hemorrhage, leukopenia, abortion, and high mortality. The etiological agent, CSF virus (CSFV), is classified as a Pestivirus, along with Bovine Viral Diarrhea Virus (BVDV) and Border Disease Virus...

  9. The Ep152R ORF of African swine fever virus strain Georgia encodes for an essential gene that interacts with host protein BAG6.

    Science.gov (United States)

    Borca, Manuel V; O'Donnell, Vivian; Holinka, Lauren G; Rai, Devendra K; Sanford, Brenton; Alfano, Marialexia; Carlson, Jolene; Azzinaro, Paul A; Alonso, Covadonga; Gladue, Douglas P

    2016-09-01

    African swine fever virus (ASFV) is the etiological agent of a contagious and often lethal disease of domestic pigs that has significant economic consequences for the swine industry. The viral genome encodes for more than 150 genes, and only a select few of these genes have been studied in some detail. Here we report the characterization of open reading frame Ep152R that has a predicted complement control module/SCR domain. This domain is found in Vaccinia virus proteins that are involved in blocking the immune response during viral infection. A recombinant ASFV harboring a HA tagged version of the Ep152R protein was developed (ASFV-G-Ep152R-HA) and used to demonstrate that Ep152R is an early virus protein. Attempts to construct recombinant viruses having a deleted Ep152R gene were consistently unsuccessful indicating that Ep152R is an essential gene. Interestingly, analysis of host-protein interactions for Ep152R using a yeast two-hybrid screen, identified BAG6, a protein previously identified as being required for ASFV replication. Furthermore, fluorescent microscopy analysis confirms that Ep152R-BAG6 interaction actually occurs in cells infected with ASFV. PMID:27497620

  10. Vaccine Potential of Two Previously Uncharacterized African Swine Fever Virus Isolates from Southern Africa and Heterologous Cross Protection of an Avirulent European Isolate.

    Science.gov (United States)

    Souto, R; Mutowembwa, P; van Heerden, J; Fosgate, G T; Heath, L; Vosloo, W

    2016-04-01

    African swine fever (ASF) is a mostly fatal viral infection of domestic pigs for which there is no vaccine available. The disease is endemic to most of sub-Saharan Africa, causes severe losses and threatens food security in large parts of the continent. Naturally occurring attenuated ASF viruses have been tested as vaccine candidates, but protection was variable depending on the challenge virus. In this study, the virulence of two African isolates, one from a tick vector and the other from an indigenous pig, was determined in domestic pigs to identify a potential vaccine strain for southern Africa. Neither isolate was suitable as the tick isolate was moderately virulent and the indigenous pig virus was highly virulent. The latter was subsequently used as heterologous challenge in pigs first vaccinated with a naturally attenuated isolate previously isolated in Portugal. Although a statistically significant reduction in death rate and virus load was observed compared with unvaccinated pigs post-challenge, all pigs succumbed to infection and died. PMID:25073549

  11. Prostaglandin A1 Inhibits Replication of Classical Swine Fever Virus

    OpenAIRE

    Tânia Rosária Pereira Freitas; Lucio Ayres Caldas; Moacyr Alcoforado Rebello

    1998-01-01

    Prostaglandins (Pgs) have been shown to inhibit the replication of several DNA and RNA viruses. Here we report the effect of prostaglandin (PgA1) on the multiplication of a positive strand RNA virus, Classical Swine Fever Virus (CSFV) in PK15 cells. PgA1 was found to inhibit the multiplication of CSFV. At a concentration of 5 µg/ml, which was nontoxic to the cells, PgA1 inhibitis virus production in 99%. In PgA1 treated cells the size and number of characteristic Classical Swine Fever focus d...

  12. Prostaglandin A1 Inhibits Replication of Classical Swine Fever Virus

    Directory of Open Access Journals (Sweden)

    Tânia Rosária Pereira Freitas

    1998-11-01

    Full Text Available Prostaglandins (Pgs have been shown to inhibit the replication of several DNA and RNA viruses. Here we report the effect of prostaglandin (PgA1 on the multiplication of a positive strand RNA virus, Classical Swine Fever Virus (CSFV in PK15 cells. PgA1 was found to inhibit the multiplication of CSFV. At a concentration of 5 µg/ml, which was nontoxic to the cells, PgA1 inhibitis virus production in 99%. In PgA1 treated cells the size and number of characteristic Classical Swine Fever focus decreased in amount.

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

    OpenAIRE

    Guo Huan-cheng; Shi Zi-xue; Sun Jin-fu; Li Su; Tu Chang-chun

    2011-01-01

    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 inocula...

  14. Molecular monitoring of African swine fever virus using surveys targeted at adult Ornithodoros ticks : a re-evaluation of Mkuze Game Reserve, South Africa

    Directory of Open Access Journals (Sweden)

    L.F. Arnot

    2009-09-01

    Full Text Available The Mkuze Game Reserve (MGR, in north-eastern KwaZulu-Natal Province, South Africa is an African swine fever virus (ASF controlled area. In a survey conducted in 1978, ASF prevalence in warthogs and Ornithodoros ticks in MGR was determined to be 2 % and 0.06 %, respectively. These values, acknowledged as being unusually low compared to other East and southern African ASF-positive sylvatic-cycle host populations, have not been assessed since. The availability of a sensitive PCR-based virus detection method, developed specifically for the sylvatic tampan host, prompted a re-evaluation of ASF virus (ASFV prevalence in MGR ticks. Of the 98 warthog burrows inspected for Ornithodoros presence, 59 (60.2 % were found to contain tampans and tick sampling was significantly male-biased. Whilst gender sampling-bias is not unusual, the 27 % increase in infestation rate of warthog burrows since the 1978 survey is noteworthy as it anticipates a concomitant increase in ASFV prevalence, particularly in light of the high proportion (75 % of adult ticks sampled. However, despite DNA integrity being confirmed by internal control amplification of the host 16S gene, PCR screening failed to detect ASFV. These results suggest that ASFV has either disappeared from MGR or if present, is localized, occurring at exceptionally low levels. Further extensive surveys are required to establish the ASFV status of sylvatic hosts in this controlled area.

  15. African swine fever virus Georgia isolate harboring deletions of 9GL and MGF360/505 genes is highly attenuated in swine but does not confer protection against parental virus challenge.

    Science.gov (United States)

    O'Donnell, Vivian; Holinka, Lauren G; Sanford, Brenton; Krug, Peter W; Carlson, Jolene; Pacheco, Juan M; Reese, Bo; Risatti, Guillermo R; Gladue, Douglas P; Borca, Manuel V

    2016-08-01

    African swine fever virus (ASFV) produces a contagious disease of domestic pigs that results in severe economic consequences to the swine industry. Control of the disease has been hampered by the unavailability of vaccines. We recently reported the development of two experimental vaccine strains (ASFV-G-Δ9GL and ASFV-G-ΔMGF) based on the attenuation of the highly virulent and epidemiologically relevant Georgia2007 isolate. Deletion of the 9GL gene or six genes of the MGF360/505 group produced two attenuated ASFV strains which were able to confer protection to animals when challenged with the virulent parental virus. Both viruses, although efficient in inducing protection, present concerns regarding their safety. In an attempt to solve this problem we developed a novel virus strain, ASFV-G-Δ9GL/ΔMGF, based on the deletion of all genes deleted in ASFV-G-Δ9GL and ASFV-G-ΔMGF. ASFV-G-Δ9GL/ΔMGF is the first derivative of a highly virulent ASFV field strain subjected to a double round of recombination events seeking to sequentially delete specific genes. ASFV-G-Δ9GL/ΔMGF showed a decreased ability to replicate in primary swine macrophage cultures relative to that of ASFV-G and ASFV-G-ΔMGF but similar to that of ASFV-G-Δ9GL. ASFV-G-Δ9GL/ΔMGF was attenuated when intramuscularly inoculated into swine, even at doses as high as 10(6) HAD50. Animals infected with doses ranging from 10(2) to 10(6) HAD50 did not present detectable levels of virus in blood at any time post-infection and they did not develop detectable levels of anti-ASFV antibodies. Importantly, ASFV-G-Δ9GL/ΔMGF does not induce protection against challenge with the virulent parental ASFV-G isolate. Results presented here suggest caution towards approaches involving genomic manipulations when developing rationally designed ASFV vaccine strains. PMID:27182007

  16. Mutations in classical swine fever virus NS4B affect virulence in swine

    Science.gov (United States)

    NS4B is one of the non-structural proteins of Classical Swine Fever Virus (CSFV), a virus causing a severe disease in swine. Protein domain analysis of the predicted amino acid sequence of NS4B in highly pathogenic CSFV strain Brescia (BICv) identified a Toll/Interleukin-1 receptor like domain (TIR...

  17. Interactions of the DNA Polymerase X From African Swine Fever Virus With the ssDNA. Properties of the Total DNA-Binding Site and the Strong DNA-Binding Subsite§

    OpenAIRE

    Jezewska, Maria J.; Szymanski, Michal R.; Bujalowski, Wlodzimierz

    2011-01-01

    Interactions of the polymerase X from the African Swine Fever Virus with the ssDNA have been studied, using quantitative fluorescence titration and fluorescence resonance energy transfer techniques. The primary DNA-binding subsite of the enzyme, independent of the DNA conformation, is located on the C-terminal domain. Association of the bound DNA with the catalytic N-terminal domain finalizes the engagement of the total DNA-binding site of the enzyme and induces a large topological change in ...

  18. New method of antibody detection by indirect immunoperoxidase plaque staining for serodiagnosis of African swine fever.

    OpenAIRE

    Pan, I. C.; Huang, T. S.; Hess, W. R.

    1982-01-01

    An indirect immunoperoxidase plaque-staining method was developed for detecting antibody to African swine fever virus infection. In both sensitivity and specificity, the test was comparable to indirect immunofluorescence. Because it has all of the desirable features of the indirect immunofluorescence test and may also be readily used for testing large numbers of sera, the indirect immunoperoxidase plaque-staining method can be used as a single and final serodiagnostic test in a large-scale su...

  19. CD2v interacts with Adaptor Protein AP-1 during African swine fever infection

    OpenAIRE

    Pérez-Núñez, Daniel; García-Urdiales, Eduardo; Martínez Bonet, Marta; Nogal París, María Luisa; Barroso, Susana; Revilla, Yolanda; Madrid, Ricardo

    2015-01-01

    African swine fever virus (ASFV) CD2v protein is believed to be involved in virulence enhancement, viral hemadsorption, and pathogenesis, although the molecular mechanisms of the function of this viral protein are still not fully understood. Here we describe that CD2v localized around viral factories during ASFV infection, suggesting a role in the generation and/or dynamics of these viral structures and hence in disturbing cellular traffic. We show that CD2v targeted the regulatory trans-Golg...

  20. 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; McNeilly, Francis; Uttenthal, Åse; Gallardo, Carmina; Adair, Brian; Allan, Gordon

    detect any of the other common swine DNA viruses tested in this study. The assay can detect ASFV DNA in a range of clinical samples. Sensitivity was equivalent to the Office International des Epizooties (OIE) recommended TaqMan assay. In addition the assay was found to have a detection limit 10-fold more...... 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 or...

  1. Mutations in the classical swine fever virus NS4B protein affects virulence in swine

    Science.gov (United States)

    NS4B is one of the non-structural proteins of Classical Swine Fever Virus (CSFV), the etiological agent of a severe, highly lethal disease of swine. Protein domain analysis of the predicted amino acid sequence of the NS4B protein of highly pathogenic CSFV strain Brescia (BICv) identified a Toll/Inte...

  2. Investigation into the Epidemiology of African Swine Fever Virus at the Wildlife - Domestic Interface of the Gorongosa National Park, Central Mozambique.

    Science.gov (United States)

    Quembo, C J; Jori, F; Heath, L; Pérez-Sánchez, R; Vosloo, W

    2016-08-01

    An epidemiological study of African swine fever (ASF) was conducted between March 2006 and September 2007 in a rural area adjacent to the Gorongosa National park (GNP) located in the Central Mozambique. Domestic pigs and warthogs were sampled to determine the prevalence of antibodies against ASF virus and the salivary antigens of Ornithodoros spp. ticks, while ticks collected from pig pens were tested for the presence of ASFV. In addition, 310 framers were interviewed to gain a better understanding of the pig value chain and potential practices that could impact on the spread of the virus. The sero-prevalence to ASFV was 12.6% on farms and 9.1% in pigs, while it reached 75% in warthogs. Approximately 33% of pigs and 78% of warthogs showed antibodies against salivary antigens of ticks. The differences in sero-prevalence between farms close to the GNP, where there is greater chance for the sylvatic cycle to cause outbreaks, and farms located in the rest of the district, where pig to pig transmission is more likely to occur, were marginally significant. Ornithodoros spp. ticks were found in only 2 of 20 pig pens outside the GNP, and both pens had ticks testing positive for ASFV DNA. Interviews carried out among farmers indicated that biosecurity measures were mostly absent. Herd sizes were small with pigs kept in a free-ranging husbandry system (65%). Only 1.6% of farmers slaughtered on their premises, but 51% acknowledged allowing visitors into their farms to purchase pigs. ASF outbreaks seemed to have a severe economic impact with nearly 36% of farmers ceasing pig farming for at least 1 year after a suspected ASF outbreak. This study provides the first evidence of the existence of a sylvatic cycle in Mozambique and confirms the presence of a permanent source of virus for the domestic pig value chain. PMID:25483914

  3. Sumoylation of the Core Protein in Classical Swine Fever Virus is Essential for Virulence in swine

    Science.gov (United States)

    The classical swine fever virus core protein makes up the nucleocapsid of the virus, and is serves both as a protective function for the viral RNA and a transcriptional regulator in the host cell. To identify host proteins that interact with the viral Core protein we utilized the yeast two-hybrid to...

  4. Genetic variability and distribution of Classical swine fever virus.

    Science.gov (United States)

    Beer, Martin; Goller, Katja V; Staubach, Christoph; Blome, Sandra

    2015-06-01

    Classical swine fever is a highly contagious disease that affects domestic and wild pigs worldwide. The causative agent of the disease is Classical swine fever virus (CSFV), which belongs to the genus Pestivirus within the family Flaviviridae. On the genome level, CSFV can be divided into three genotypes with three to four sub-genotypes. Those genotypes can be assigned to distinct geographical regions. Knowledge about CSFV diversity and distribution is important for the understanding of disease dynamics and evolution, and can thus help to design optimized control strategies. For this reason, the geographical pattern of CSFV diversity and distribution are outlined in the presented review. Moreover, current knowledge with regard to genetic virulence markers or determinants and the role of the quasispecies composition is discussed. PMID:26050570

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

    Directory of Open Access Journals (Sweden)

    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.

  6. PROTEINS OF AFRICAN SWINE FEVER VIRUS Белки вируса африканской чумы свиней

    Directory of Open Access Journals (Sweden)

    Sereda A. D.

    2012-03-01

    Full Text Available The review presents some data on structural and non-structural, regulatory proteins and enzymes of African swine fever (ASF virus. The variety of the virus biological characteristics is substantially caused by proteins belonging to multigenic families. It is suggested, that the protection development at ASF is provided not only by the membrane proteins, but also by the regulatory ones

  7. Classical Swine Fever Virus p7 protein is a viroporin involved in virulence in swine

    Science.gov (United States)

    The non-structural protein p7 of Classical Swine Fever Virus (CSFV) is a hydrophobic polypeptide with an apparent molecular mass of 7 kDa. The protein contains two hydrophobic stretches of amino acids interrupted by a short charged segment that are predicted to form transmembrane helices and a cytos...

  8. Monitoring the determinants of efficient viral replication using Classical Swine Fever Virus-reporter replicons

    DEFF Research Database (Denmark)

    Risager, Peter Christian; Everett, Helen; Crooke, Helen;

    2012-01-01

    Classical swine fever virus (CSFV) is the etiological agent of the severe porcine disease, classical swine fever. Unraveling the molecular determinants of efficient replication is crucial for gaining improved knowledge of the pathogenic features of this virus. Monitoring the replication competence...

  9. Complete Genome Sequence of Classical Swine Fever Virus Subgenogroup 2.1 from Assam, India

    OpenAIRE

    Ahuja, Anuj; Bhattacharjee, Uttaran; Chakraborty, Amit Kumar; Karam, Amarjit; Ghatak, Sandeep; Puro, Kekungu; Das, Samir; Shakuntala, Ingudam; Srivastava, Nidhi; Ngachan, S.V.; Sen, Arnab

    2015-01-01

    We report the complete genome sequence of a classical swine fever virus (genogroup 2.1), isolated from an outbreak in Assam, India. This particular isolate showed a high degree of genetic variation within the subgenogroup 2.1 and may serve as a potential reference strain of the 2.1 genogroup of classical swine fever virus (CSFV) in the Indian subcontinent.

  10. 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

    amplified and inserted into dicistronic reporter plasmids encoding Fluc and Rluc under the control of a T7 promoter. The mutations were within domains II, IIId1 and IIIf of the IRES. The plasmids were transfected into BHK cells infected with the recombinant vaccinia virus, vTF7-3, which expresses the T7 RNA...... 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......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...

  11. Different evolutionary patterns of classical swine fever virus envelope proteins.

    Science.gov (United States)

    Li, Yan; Yang, Zexiao; Zhang, Mingwang

    2016-03-01

    Classical swine fever virus (CSFV) is the causative agent of classical swine fever, which is a highly contagious disease of the domestic pig as well as wild boar. The proteins E(rns), E1, and E2 are components of the viral envelope membrane. They are also implicated in virus attachment and entry, replication, and (or) anti-immune response. Here, we studied the genetic variations of these envelope proteins in the evolution of CSFV. The results reveal that the envelope proteins underwent different evolutionary fates. In E(rns) and E1, but not E2, a number of amino acid sites experienced functional divergence. Furthermore, the diversification in E(rns) and E1 was generally episodic because the divergence-related changes of E1 only occurred with the separation of 2 major groups of CSFV and that of E(rns) took place with the division of 1 major group. The major divergence-related sites of E(rns) are located on one of the substrate-binding regions of the RNase domain and C-terminal extension. These functional domains have been reported to block activation of the innate immune system and attachment and entry into host cells, respectively. Our results may shed some light on the divergent roles of the envelope proteins. PMID:26911308

  12. Discovering up-regulated VEGF–C expression in swine umbilical vein endothelial cells by classical swine fever virus Shimen

    OpenAIRE

    Ning, Pengbo; Zhang, Yanming; Guo, Kangkang; Chen, Ru; Liang, Wulong; Lin, Zhi; Li, Helin

    2014-01-01

    International audience Infection of domestic swine with the highly virulent Shimen strain of classical swine fever virus causes hemorrhagic lymphadenitis and diffuse hemorrhaging in infected swine. We analyzed patterns of gene expression for CSFV Shimen in swine umbilical vein endothelial cells (SUVECs). Transcription of the vascular endothelial growth factor (VEGF) C gene (VEGF-C) and translation of the corresponding protein were significantly up-regulated in SUVECs. Our findings suggest ...

  13. 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 (10km. The close social relationships between actors in pig movement networks indicate the potential for possible interventions to develop shared norms and mutually accepted

  14. Identification of an NTPase motif in classical swine fever virus NS4B protein

    Science.gov (United States)

    Classical swine fever (CSF) is a highly contagious and often fatal disease of swine caused by CSF virus (CSFV), a positive sense single-stranded RNA virus in the genus Pestivirus of the Flaviviridae family. Here, we have identified, within CSFV non-structural (NS) protein NS4B, conserved sequence el...

  15. Complete Genome Sequence of Classical Swine Fever Virus Genotype 2.2 Strain Bergen

    OpenAIRE

    Fahnøe, Ulrik; Lohse, Louise; Becher, Paul; Rasmussen, Thomas Bruun

    2014-01-01

    The complete genome sequence of the genotype 2.2 classical swine fever virus strain Bergen has been determined; this strain was originally isolated from persistently infected domestic pigs in the Netherlands and is characterized to be of low virulence.

  16. 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

    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......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...... 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...

  17. Complete Genome Sequence of Classical Swine Fever Virus Genotype 2.2 Strain Bergen

    DEFF Research Database (Denmark)

    Fahnøe, Ulrik; Lohse, Louise; Becher, Paul;

    2014-01-01

    The complete genome sequence of the genotype 2.2 classical swine fever virus strain Bergen has been determined; this strain was originally isolated from persistently infected domestic pigs in the Netherlands and is characterized to be of low virulence.......The complete genome sequence of the genotype 2.2 classical swine fever virus strain Bergen has been determined; this strain was originally isolated from persistently infected domestic pigs in the Netherlands and is characterized to be of low virulence....

  18. Patterns of Cellular Gene Expression in Swine Macrophages Infected with Highly Virulent Classical Swine Fever Virus Strain Brescia

    Science.gov (United States)

    Experimental exposure of swine to highly virulent Classical Swine Fever Virus (CSFV) strain Brescia causes an invariably fatal disease of all infected animals by 8 to 14 days post-infection. Host mechanisms involved in this severe outcome of infection have not been clearly established. To understa...

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

    Science.gov (United States)

    2010-01-01

    ... Drug Administration at 21 CFR 589.2000 may be imported. (2) Casings that are derived from bovines that... swine fever and bovine spongiform encephalopathy. 96.2 Section 96.2 Animals and Animal Products ANIMAL... ENTRY INTO THE UNITED STATES § 96.2 Prohibition of casings due to African swine fever and...

  20. Detection of the classical swine fever virus antigen following experimental infection

    OpenAIRE

    Milanov Dubravka; Ašanin Ružica; Đurišić Slavko; Suvajdžić Ljiljana; Lazić Sava

    2002-01-01

    In this experiment, twelve pigs were infected by intramuscular inoculation of virulent virus strains of classical swine fever (Baker, Kansas, BAI autochthonic isolate). Three animals survived infection without any clinical symptoms and were sacrificed 60 days post infection (p.i). Nine animals developed an acute form of classical swine fever and died between 8 and 15 days p.i. Rectal temperature was monitored daily along with the clinical symptoms and usual hematological parameters. Viremia w...

  1. Detection and genotyping of classical swine fever virus isolates in Serbia

    OpenAIRE

    Milićević Vesna; Radojičić Sonja; Valčić A.M.; Ivović V.; Maksimović-Zorić Jelena; Radosavljević V.

    2013-01-01

    Classical swine fever (CSF) is a highly contagious disease of pigs leading to significant economic losses worldwide. Classical swine fever virus can be classified into three genogroups, each consisting of three or four subgroups. However, there is a lack of knowledge on the genotypes of CSFV isolates in Republic of Serbia. This study, based on the sequences analysis of partial E2 gene and 5' non coding region (NCR) of 15 CSFV isolated during 2006-2008 from ...

  2. Integrin β3 Is Required in Infection and Proliferation of Classical Swine Fever Virus

    OpenAIRE

    Weiwei Li; Gang Wang; Wulong Liang; Kai Kang; Kangkang Guo; Yanming Zhang

    2014-01-01

    Classical Swine Fever (CSF) is a highly infectious fatal pig disease, resulting in huge economic loss to the swine industry. Integrins are membrane-bound signal mediators, expressed on a variety of cell surfaces and are known as receptors or co-receptors for many viruses. However, the role of integrin β3 in CSFV infection is unknown. Here, through quantitive PCR, immunofluorescence (IFC) and immunocytohistochemistry (ICC), we revealed that ST (swine testicles epithelial) cells have a prominen...

  3. Review of African swine fever : transmission, spread and control : review article

    Directory of Open Access Journals (Sweden)

    M-L. Penrith

    2009-05-01

    Full Text Available African swine fever is one of the most important and serious diseases of domestic pigs. Its highly contagious nature and ability to spread over long distances make it one of the most feared diseases, since its devastating effects on pig production have been experienced not only in most of sub-Saharan Africa but also in western Europe, the Caribbean, Brazil and, most recently, the Caucasus. Unlike most diseases of livestock, there is no vaccine, and therefore prevention relies entirely upon preventing contact between the virus and the susceptible host. In order to do so it is necessary to understand the way in which the virus is transmitted and spreads. By implementing strict biosecurity measures that place barriers between the source of virus and the pigs it is possible to prevent infection. However, this has implications for free-ranging pig husbandry systems that are widespread in developing countries. Attempts to produce a vaccine are ongoing and new technology offers some hope for the future, but this will not remove the necessity for implementing adequate biosecurity on pig farms.

  4. [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. PMID:16796039

  5. A longitudinal survey of African swine fever in Uganda reveals high apparent disease incidence rates in domestic pigs, but absence of detectable persistent virus infections in blood and serum

    OpenAIRE

    Muhangi, Denis; Masembe, Charles; Emanuelson, Ulf; Boqvist, Sofia; Mayega, Lawrence; Ademun, Rose Okurut; Bishop, Richard P.; Ocaido, Michael; Berg, Mikael; Ståhl, Karl

    2015-01-01

    Background African swine fever (ASF) is a fatal, haemorrhagic disease of domestic pigs, that poses a serious threat to pig farmers and is currently endemic in domestic pigs in most of sub-Saharan Africa. To obtain insight into the factors related to ASF outbreaks at the farm-level, a longitudinal study was performed in one of the major pig producing areas in central Uganda. Potential risk factors associated with outbreaks of ASF were investigated including the possible presence of apparently ...

  6. Classical and African swine fever in domestic pigs and European wild boar

    OpenAIRE

    Gabriel, Claudia

    2012-01-01

    Classical and African swine fever are highly contagious, notifiable viral diseases affecting different members of the Suidae family, both showing tremendous impact on animal health and pig production. Optimization of CSF control strategies comprised two different approaches. In a first step, the current strategy of oral immunization of wild boar using a conventional C-strain vaccine was supplemented with the implementation of genetic DIVA using a recently developed multiplex rRT-PCR assay....

  7. Review of African swine fever : transmission, spread and control : review article

    OpenAIRE

    M-L Penrith; W. Vosloo

    2009-01-01

    African swine fever is one of the most important and serious diseases of domestic pigs. Its highly contagious nature and ability to spread over long distances make it one of the most feared diseases, since its devastating effects on pig production have been experienced not only in most of sub-Saharan Africa but also in western Europe, the Caribbean, Brazil and, most recently, the Caucasus. Unlike most diseases of livestock, there is no vaccine, and therefore prevention relies entirely upon pr...

  8. Insights from social network analysis are helping to build understanding of African Swine Fever epidemiology

    OpenAIRE

    Lichoti, Jacqueline K.; Davies, Jocelyn; Okoth, Edward; Maru, Yiheyis; Bishop, Richard

    2013-01-01

    Pig movements are likely to play a signficant role in the spread of important infectious diseases such as the African Swine Fever. Characterization of movement networks from farm-to-farm and through other types of farm or household operations can provide useful information on the role that networks play in acquiring and spreading infectious diseases. Analysis of social networks that underpin these pig movements can also reveal structures that are important in the transmission of disease, trad...

  9. CD2v Interacts with Adaptor Protein AP-1 during African Swine Fever Infection.

    Directory of Open Access Journals (Sweden)

    Daniel Pérez-Núñez

    Full Text Available African swine fever virus (ASFV CD2v protein is believed to be involved in virulence enhancement, viral hemadsorption, and pathogenesis, although the molecular mechanisms of the function of this viral protein are still not fully understood. Here we describe that CD2v localized around viral factories during ASFV infection, suggesting a role in the generation and/or dynamics of these viral structures and hence in disturbing cellular traffic. We show that CD2v targeted the regulatory trans-Golgi network (TGN protein complex AP-1, a key element in cellular traffic. This interaction was disrupted by brefeldin A even though the location of CD2v around the viral factory remained unchanged. CD2v-AP-1 binding was independent of CD2v glycosylation and occurred on the carboxy-terminal part of CD2v, where a canonical di-Leu motif previously reported to mediate AP-1 binding in eukaryotic cells, was identified. This motif was shown to be functionally interchangeable with the di-Leu motif present in HIV-Nef protein in an AP-1 binding assay. However, we demonstrated that it was not involved either in CD2v cellular distribution or in CD2v-AP-1 binding. Taken together, these findings shed light on CD2v function during ASFV infection by identifying AP-1 as a cellular factor targeted by CD2v and hence elucidate the cellular pathways used by the virus to enhance infectivity.

  10. 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...

  11. 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

    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...

  12. Effects of the interactions of classical swine fever virus core protein with proteins of SUMOylation pathway on virulence in swine

    Science.gov (United States)

    The classical swine fever virus (CSFV) nucleocapsid or Core protein serves a protective function for the viral RNA, and acts as a transcriptional regulator. However studies involving the CSFV Core protein have been limited. To gain insight into other functions of the Core protein, particularly into ...

  13. Quantitative assessment of the likelihood of the introduction of classical swine fever virus into the Danish swine population

    DEFF Research Database (Denmark)

    Bronsvoort, BMD; Alban, L.; Greiner, M.

    2008-01-01

    Classical swine fever virus (CSFV) is a major infectious-disease agent of livestock and causes production losses through increased morbidity and mortality, particularly of young pigs. We identified the pathways for introduction of CSFV into Denmark and assessed the annual probability of...

  14. Interaction between core protein of classical swine fever virus with cellular IQGAP1 proetin appears essential for virulence in swine

    Science.gov (United States)

    Here we show that IQGAP1, a cellular protein that plays a pivotal role as a regulator of the cytoskeleton affecting cell adhesion, polarization and migration, interacts with Classical Swine Fever Virus (CSFV) Core protein. Sequence analyses identified a defined set of residues within CSFV Core prote...

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

    DEFF Research Database (Denmark)

    Uttenthal, Åse

    2012-01-01

    The Danish (National Veterinary) Expert group for Classical and African swine fever has been active during the last 10 years. The group is composed of experts in EU-legislation, in Danish pig production, in pig diseases and in virology. The group has participated in a national workshop on CSFV...... 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...

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

    Science.gov (United States)

    Magadla, Noluvuyo R; Vosloo, Wilna; Heath, Livio; Gummow, Bruce

    2016-01-01

    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. PMID:27247068

  17. Immune Responses Against Classical Swine Fever Virus: Between Ignorance and Lunacy

    OpenAIRE

    Summerfield, Artur; Ruggli, Nicolas

    2015-01-01

    Classical swine fever virus infection of pigs causes disease courses from life-threatening to asymptomatic, depending on the virulence of the virus strain and the immunocompetence of the host. The virus targets immune cells, which are central in orchestrating innate and adaptive immune responses such as macrophages and conventional and plasmacytoid dendritic cells. Here, we review current knowledge and concepts aiming to explain the immunopathogenesis of the disease at both the host and the c...

  18. Cytopathogenicity of classical swine fever virus caused by defective interfering particles.

    OpenAIRE

    Meyers, G; Thiel, H J

    1995-01-01

    For three independent cytopathogenic isolates of classical swine fever virus, defective RNAs were found in infected cells in addition to full-length viral genomes. These RNAs represent the genomes of typical defective interfering (DI) particles because of strict dependence on a complementing helper virus and interference with the replication of the helper virus. Analysis of the DI genomes revealed internal deletions of 4,764 nucleotides encompassing the complete structural protein-coding regi...

  19. 9 CFR 94.10 - Swine from regions where classical swine fever exists.

    Science.gov (United States)

    2010-01-01

    ... IMPORTATIONS § 94.10 Swine from regions where classical swine fever exists. (a) Classical swine fever is known... swine fever exists. 94.10 Section 94.10 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION... PRODUCTS RINDERPEST, FOOT-AND-MOUTH DISEASE, EXOTIC NEWCASTLE DISEASE, AFRICAN SWINE FEVER, CLASSICAL......

  20. Complete Genome Sequence of an Indian Field Isolate of Classical Swine Fever Virus Belonging to Subgenotype 1.1

    OpenAIRE

    Kamboj, Aman; Patel, Chhabi L.; Chaturvedi, V.K.; Saini, Mohini; Praveen K. Gupta

    2014-01-01

    We report the complete genome sequence of an Indian field isolate of classical swine fever virus (CSFV) belonging to predominant subgenotype 1.1 prevalent in India. This report will help in understanding the molecular diversity of CSFV strains circulating worldwide and to select and develop a suitable vaccine candidate for classical swine fever (CSF) control in India.

  1. 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

    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. In...

  2. 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 stable...

  3. Effects of glycosylation on antigenicity and immunogenicity of classical swine fever virus envelope proteins

    Science.gov (United States)

    Classical swine fever virus (CSFV) harbors three envelope glycoproteins (E(rns), E1 and E2). Previous studies have demonstrated that removal of specific glycosylation sites within these proteins yielded attenuated and immunogenic CSFV mutants. Here we analyzed the effects of lack of glycosylation of...

  4. Classical Swine Fever Virus Inhibits Nitric Oxide Production in Infected Macrophages

    Science.gov (United States)

    Classical swine fever virus (CSFV)-macrophage interactions during infection were analyzed by examining macrophage transcriptional responses via microarray. Eleven genes had increased mRNA levels (>2.5 fold, p<0.05) in infected cell cultures including arginase-1, an inhibitor of nitric oxide producti...

  5. Time-Calibrated Phylogenomics of the Classical Swine Fever Viruses: Genome-Wide Bayesian Coalescent Approach

    OpenAIRE

    Kwon, Taehyung; Yoon, Sook Hee; Kim, Kyu-Won; Caetano-Anolles, Kelsey; Cho, Seoae; Kim, Heebal

    2015-01-01

    The phylogeny of classical swine fever virus (CSFV), the causative agent of classical swine fever (CSF), has been investigated extensively. However, no evolutionary research has been performed using the whole CSFV genome. In this study, we used 37 published genome sequences to investigate the time-calibrated phylogenomics of CSFV. In phylogenomic trees based on Bayesian inference (BI) and Maximum likelihood (ML), the 37 isolates were categorized into five genetic types (1.1, 1.2, 2.1, 2.3, an...

  6. Immune responses against classical swine fever virus: between ignorance and lunacy

    Directory of Open Access Journals (Sweden)

    Artur eSummerfield

    2015-05-01

    Full Text Available Classical swine fever virus infection of pigs causes disease courses from life-threatening to asymptomatic, depending on the virulence of the virus strain and the immunocompetence of the host. The virus targets immune cells which are central in orchestrating innate and adaptive immune responses such as macrophages and conventional and plasmacytoid dendritic cells. Here we review current knowledge and concepts aiming to explain the immunopathogenesis of the disease at both the host and the cellular level. We propose that the interferon type I system and in particular the interaction of the virus with plasmacytoid dendritic cells and macrophages is crucial to understand elements governing the induction of protective rather than pathogenic immune responses. The review also concludes that despite the knowledge available many aspects of classical swine fever immunopathogenesis are still puzzling.

  7. Development of single dilution immunoassay to detect E2 protein specific classical swine fever virus antibody.

    Science.gov (United States)

    Kumar, Rakesh; Barman, Nagendra N; Khatoon, Elina; Kumar, Sachin

    2016-04-01

    Classical swine fever virus (CSFV) is the causative agent of a highly contagious disease in swine. The disease is endemic in different parts of the world and vaccination is the only way to protect pigs from CSFV infection. The virus surface protein E2 is the major immunogenic protein eliciting protective immunity against CSFV infection in swine. The whole virus antigen cannot differentiate CSFV from other pestiviruses as it cross reacts with border disease and bovine viral diarrhoea viruses. Commercial available ELISA is based on the whole CSFV particle and can lead to false positive results. Moreover, the available commercial ELISA is not cost effective. In the present study, a recombinant E2 protein based single serum dilution ELISA was developed which showed enhanced sensitivity, specificity and accuracy as compared to commercial CSFV detection ELISA. The recombinant E2 protein based ELISA could be an alternate to existing diagnostics against CSFV infection in pigs. PMID:27032503

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

    OpenAIRE

    Fahnøe, Ulrik; Orton, Richard; Höper, Dirk; Beer, Martin; Rasmussen, Thomas Bruun

    2014-01-01

    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.

  9. Mutations in the Carboxi Terminal Region of E2 Glycoprotein of Classical Swine Fever Virus is Responsible for Viral Attenuation in Swine

    Science.gov (United States)

    We have reported that chimeric virus 319.1 virus containing the E2 glycoprotein gene from Classical Swine Fever Virus (CSFV) vaccine strain CS with the genetic background of virulent CSFV strain Brescia (BIC virus) was attenuated in pigs. To identify the amino acids mediating 319.1 virus attenuation...

  10. Survival of classical swine fever virus at various temperatures in faeces and urine derived from experimentally infected pigs

    OpenAIRE

    Weesendorp, E.; Stegeman, J.A.; Loeffen, W. L. A.

    2008-01-01

    Survival of classical swine fever virus at various temperatures in faeces and urine derived from experimentally infected pigs NETHERLANDS (Weesendorp, Eefke) NETHERLANDS Received: 2008-03-27 Revised: 2008-05-19 Accepted: 2008-05-26

  11. Quantification of classical swine fever virus in aerosols originating from pigs infected with strains of high, moderate or low virulence

    OpenAIRE

    Weesendorp, Eefke; Stegeman, Arjan; Loeffen, Willie L.A.

    2009-01-01

    Quantification of classical swine fever virus in aerosols originating from pigs infected with strains of high, moderate or low virulence NETHERLANDS (Weesendorp, Eefke) NETHERLANDS Received: 2008-07-15 Revised: 2008-08-27 Accepted: 2008-09-15

  12. Prevalence of African swine fever viral antigens in slaughter pigs at Nalukolongo abattoir, Kampala, Uganda

    Directory of Open Access Journals (Sweden)

    P. Sajjakambwe,

    2011-05-01

    Full Text Available The underdevelopment of the African pig industry is widely attributed to African swine fever (ASF. Outbreaks of the disease occur in different parts of Uganda almost annually although cases are rarely confirmed. We conducted an abattoir based survey of ASF associated lymph node lesions to establish the status of the disease in apparently healthy pigs. Highly suspicious lesions were subjected to immunohistochemistry for viral antigen detection. Most lymph nodes with follicular necrosis, parenchymal haemorrhage and lymphoid depletion were positive to ASF antigens. Up to 22 (0.1% of the 258 pigs from which samples were collected were positive to ASF viral antigens. We conclude that domestic pigs in Uganda can act as reservoirs of the disease i.e. sustenance of the disease in pig populations may not be entirely dependent on the sylvatic cycle.

  13. Safety assessment in pigs of an experimental molecule with in-vitro antiviral activity against African swine fever

    Czech Academy of Sciences Publication Activity Database

    Roels, S.; Van der Heyden, S.; Neyts, J.; Krečmerová, Marcela; Koenen, F.; Cay, A. B.; Tignon, M.

    Elsevier. Roč. 148, č. 1 (2013), s. 94-94. ISSN 0021-9975. [Meeting of the European Society of Veterinary Pathology /30./. 05.08.2013-08.08.2013, León] Institutional support: RVO:61388963 Keywords : African swine fever * HPMPDAP * acyclic nucleoside phosphonate * toxicity Subject RIV: CC - Organic Chemistry

  14. Complete Genome Sequences of Classical Swine Fever Virus Strains Isolated from Wild Boars in South Korea

    OpenAIRE

    Jeoung, Hye-Young; Lim, Ji-Ae; Lim, Seong-In; Kim, Jae-Jo; SONG, Jae-Young; Hyun, Bang-Hun; KIM, Yong Kwan; An, Dong-Jun

    2013-01-01

    Classical swine fever is a disease that is devastating the pig industry worldwide. Here, we report the complete genome sequences of two classical swine virus strains (YC11WB and PC11WB), isolated from Korean wild boars in 2011. Both strains belong to subgenotype 2.1b. The complete genome sequences of PC11WB and YC11WB are more similar to that of strain ZJ0801 (isolated in China) than to that of the SW03 strain isolated from domestic pigs in South Korea.

  15. Detection and genotyping of classical swine fever virus isolates in Serbia

    Directory of Open Access Journals (Sweden)

    Milićević Vesna

    2013-01-01

    Full Text Available Classical swine fever (CSF is a highly contagious disease of pigs leading to significant economic losses worldwide. Classical swine fever virus can be classified into three genogroups, each consisting of three or four subgroups. However, there is a lack of knowledge on the genotypes of CSFV isolates in Republic of Serbia. This study, based on the sequences analysis of partial E2 gene and 5' non coding region (NCR of 15 CSFV isolated during 2006-2008 from domestic pigs, revealed that all were clustered into genetic group 2.3. Additionally, we showed that the two most often used real time RT-PCR assays were able to detect all local CSF viruses circulated in Serbia in the last years during intensive vaccination campaign against CSF. [Projekat Ministarstva nauke Republike Srbije, br. TR 31075 and TR 31088

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

    OpenAIRE

    Rasmussen, Thomas Bruun; Reimann, I; Uttenthal, Åse; De Beer, M.

    2011-01-01

    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 stable 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 infec...

  17. Genomic Sequence Determination of Classical Swine Fever Virus Persistent Infection Strain

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Full genomic sequence of a newly isolated persistent infection strain of classical swine fever virus was firstly determined. It was demonstrated by sequence analyses that nucleotides homologies of this strain compared with virulent Shimen and vaccine HCLV were 89. 7% and 87.7% , and homologies of amino acids were 94. 8% and 93.3% , respectively. The sequencing results primarily suggest a tighter relationship between this persistent infection strain and virulent Shimen strain than vaccine HCLV strain.

  18. Interaction of structural core protein of Classical Swine Fever Virus with endoplasmic reticulum-associated degradation pathway protein OS9

    Science.gov (United States)

    Classical Swine Fever Virus (CSFV) Core protein is involved in virus RNA protection, transcription regulation and virus virulence. To discover additional Core protein functions a yeast two-hybrid system was used to identify host proteins that interact with Core. Among the identified host proteins, t...

  19. Identification of a Novel Virulence Determinant Within the E2 Structural Glycoprotein of Classical Swine Fever Virus

    Science.gov (United States)

    Classical Swine Fever Virus (CSFV) E2 glycoprotein contains a discrete epitope (TAVSPTTLR, residues 829-837 of CSFV polyprotein) recognized by monoclonal antibody (mAb) WH303, used to differentiate CSFV from related ruminant Pestiviruses, Bovine Viral Diarrhea Virus (BVDV) and Border Disease Virus ...

  20. A Promising Trigene Recombinant Human Adenovirus Vaccine Against Classical Swine Fever Virus.

    Science.gov (United States)

    Li, Helin; Gao, Rui; Zhang, Yanming

    2016-05-01

    Classical swine fever (CSF) vaccine based on HAdV-5 had achieved an efficient protection in swine. Both classical swine fever virus (CSFV) E0 glycoprotein and E2 glycoprotein were the targets for neutralizing antibodies and related to immune protection against CSF. Interleukin-2 (IL2), as an adjuvant, also had been used in CSF vaccine research. In this study, coexpression of the CSFV E0, E2, and IL2 genes by HAdV-5 (rAdV-E0-E2-IL2) was constructed and immunized to evaluate its efficacy. Three expressed genes had been sequentially connected with foot-and-mouth disease virus 2A (FMDV 2A). The vaccine was administered by intramuscular inoculation to CSFV-free pigs (10(8) TCID50) twice at triweekly intervals. No adverse clinical signs were observed in any of the pigs after vaccination. The vaccine induced strong humoral and cellular responses that led to complete protection against clinical signs of lethal CSFV infection, viremia, and shedding of challenge virus. The rAdV-E0-E2-IL2 is a promising, efficient, and safe marker vaccine candidate against CSFV. PMID:26918463

  1. Deteksi Virus Classical Swine Fever di Bali dengan RT-PCR

    Directory of Open Access Journals (Sweden)

    I Wayan Wirata

    2010-09-01

    Full Text Available Classical Swine Fever (CSF virus has been confirmed for the first time in pig in Bali. The object of thisstudy was suspected CSF cases diagnosed at the diagnostic laboratory assistantship of the Faculty ofVeterinary Medicine, Udayana University, in 2007-2008. Total number of cases was 12. Case recordsincluded the signalment of case (breed, age, body weight, and the origin of respective case, clinical signs,post-mortem lesions, and histological pictures. CSF virus was confirmed using the standardized reversetranscriptase-polymerase chain reaction (RT-PCR for CSF from European Union. One RT-PCR productwas sequenced. CSF virus was confirmed in seven out of 12 cases (58%. The cDNA sequence wasconfirmed to be specific of CSF E2 protein coding region with 98% homology to one isolate from China thatwas available in GeneBank. Further works are recommended to elucidate the sensitivity of RT-PCR, toclarify some differential diagnose, and to find out the genetic variation of CSF virus in Bali.Key words: classical swine fever virus, Bali, RT-PCR

  2. African Swine Fever Diagnosis Adapted to Tropical Conditions by the Use of Dried-blood Filter Papers.

    Science.gov (United States)

    Randriamparany, T; Kouakou, K V; Michaud, V; Fernández-Pinero, J; Gallardo, C; Le Potier, M-F; Rabenarivahiny, R; Couacy-Hymann, E; Raherimandimby, M; Albina, E

    2016-08-01

    The performance of Whatman 3-MM filter papers for the collection, drying, shipment and long-term storage of blood at ambient temperature, and for the detection of African swine fever virus and antibodies was assessed. Conventional and real-time PCR, viral isolation and antibody detection by ELISA were performed on paired samples (blood/tissue versus dried-blood 3-MM filter papers) collected from experimentally infected pigs and from farm pigs in Madagascar and Côte d'Ivoire. 3-MM filter papers were used directly in the conventional and real-time PCR without previous extraction of nucleic acids. Tests that performed better with 3-MM filter papers were in descending order: virus isolation, real-time UPL PCR and conventional PCR. The analytical sensitivity of real-time UPL PCR on filter papers was similar to conventional testing (virus isolation or conventional PCR) on organs or blood. In addition, blood-dried filter papers were tested in ELISA for antibody detection and the observed sensitivity was very close to conventional detection on serum samples and gave comparable results. Filter papers were stored up to 9 months at 20-25°C and for 2 months at 37°C without significant loss of sensitivity for virus genome detection. All tests on 3-MM filter papers had 100% specificity compared to the gold standards. Whatman 3-MM filter papers have the advantage of being cheap and of preserving virus viability for future virus isolation and characterization. In this study, Whatman 3-MM filter papers proved to be a suitable support for the collection, storage and use of blood in remote areas of tropical countries without the need for a cold chain and thus provide new possibilities for antibody testing and virus isolation. PMID:25430732

  3. Integrin β3 is required in infection and proliferation of classical swine fever virus.

    Directory of Open Access Journals (Sweden)

    Weiwei Li

    Full Text Available Classical Swine Fever (CSF is a highly infectious fatal pig disease, resulting in huge economic loss to the swine industry. Integrins are membrane-bound signal mediators, expressed on a variety of cell surfaces and are known as receptors or co-receptors for many viruses. However, the role of integrin β3 in CSFV infection is unknown. Here, through quantitive PCR, immunofluorescence (IFC and immunocytohistochemistry (ICC, we revealed that ST (swine testicles epithelial cells have a prominent advantage in CSFV proliferation as compared to EC (swine umbilical vein endothelial cell, IEC (swine intestinal epithelial cell and PK (porcine kidney epithelial cells. Meanwhile, ST cells had remarkably more integrin β3 expression as compared to EC, IEC and PK cells, which was positively correlated with CSFV infection and proliferation. Integrin β3 was up-regulated post CSFV infection in all the four cell lines, while the CSFV proliferation rate was decreased in integrin β3 function-blocked cells. ShRNA1755 dramatically decreased integrin β3, with a deficiency of 96% at the mRNA level and 80% at the protein level. CSFV proliferation was dramatically reduced in integrin β3 constantly-defected cells (ICDC, with the deficiencies of 92.6%, 99% and 81.7% at 24 h, 48 h and 72 h post CSFV infection, respectively. These results demonstrate that integrin β3 is required in CSFV infection and proliferation, which provide a new insight into the mechanism of CSFV infection.

  4. Sero-prevalence and risk factors associated with African swine fever on pig farms in southwest Nigeria

    OpenAIRE

    Awosanya, Emmanuel Jolaoluwa; Olugasa, Babasola; Ogundipe, Gabriel; Grohn, Yrjo Tapio

    2015-01-01

    Background African swine fever (ASF) is one of the major setbacks to development of the pig industry in Nigeria. It is enzootic in southwest Nigeria. We determined the sero-prevalence and factors associated with ASF among-herd seropositivity in 144 pig farms in six States from southwest Nigeria during the dry and rainy seasons using indirect Enzyme Linked Immunosorbent Assay (ELISA) for ASF IgG antibodies. An interviewer-administered questionnaire was used to collect information on demography...

  5. EFSA Panel on Animal Health and Welfare (AHAW); EFSA Panel on Animal Health and Welfare; Scientific Opinion on African Swine Fever

    DEFF Research Database (Denmark)

    Bøtner, Anette; Peña, Agustin Estrada; Mannelli, Alessandro;

    The risk that African Swine Fever virus (ASFV) remains endemic in the Trans Caucasian Countries (TCC) and the Russian Federation (RF) is moderate, while the risk of its spread in these regions is high. The resulting risk of introduction from these regions into the EU is moderate most likely through...... food waste. The risk of ASFV remaining endemic in wild boar and the consequent introduction into the EU was considered low in the TCC and moderate in the RF, mainly due to the higher population density in the RF and the connected wild boar populations to the EU from the RF. Within the EU, mainly...

  6. Screwworms, Cochliomyia hominivorax, Reared for Mass Release Do Not Carry and Spread Foot-and-Mouth Disease Virus and Classical Swine Fever Virus

    OpenAIRE

    Chaudhury, M. F.; Ward, G. B.; Skoda, S. R.; Deng, M Y; Welch, J. B.; McKenna, T S

    2008-01-01

    Experiments were done to determine if transporting live screwworms Cochliomyia hominivorax Coquerel (Diptera: Calliphoridae) for developing new strains from countries where foot-and-mouth disease and classical swine fever are endemic, to the mass rearing facilities in Mexico and Panama, may introduce these exotic diseases into these countries. Are screwworms capable of harboring and spreading foot-and-mouth disease virus (FMDV) and classical swine fever virus (CSFV) when they are grown in vir...

  7. Alteration of the N-linked Glycosylation Condition of E1 Glycoprotein of Classical Swine Fever Virus Strain Brescia Alters Virulence in Swine

    Science.gov (United States)

    E1, along with Erns and E2 is one of the three envelope glycoproteins of Classical Swine Fever Virus (CSFV). Previously we showed that glycosylation status of virulent CSFV strain Brescia E2 or Erns affects virus virulence. Here, the three putative glycosylation sites of E1 were serially removed by ...

  8. Construction of cytopathic PK-15 cell model of classical swine fever virus

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    No cytopathic effect (CPE) can be observed on classical swine fever virus (CSFV) infected cell culture in vitro. This brings an obstacle to the researches on reciprocity between CSFV and host cells. Based on the construction of full-length genomic infectious Cdna clone of Chinese CSFV standard virulent Shimen strain, partial deletion is intro- duced into genomic Cdna to obtain a 7.5 kb subgenomic Cdna. A new subgenomic CSFV is derived from transfection with the subgenomic Cdna on PK-15 cells pre-infected by CSFV Shimen virus. Typical CPE induced by this subgenomic virus is observed on PK-15 cells. Coexistence of wild- type and subgenomic virus in cytopathic cell culture is dem- onstrated by RT-PCR detection in cytopathic cells. For conclusion, the construction of cytopathic cell model exploited a new way for researches on the molecular mechanism of CSFV pathogenesis.

  9. 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...

  10. Processing of pestivirus polyprotein: cleavage site between autoprotease and nucleocapsid protein of classical swine fever virus.

    OpenAIRE

    Stark, R; Meyers, G; Rümenapf, T.; Thiel, H J

    1993-01-01

    The polyprotein of classical swine fever virus starts with the nonstructural protein p23, which is followed by the nucleocapsid protein p14. Proteolytic cleavage between p23 and p14 was demonstrated in a cell-free transcription-translation system. Successive truncation of the cDNA used for the transcription indicated that the proteolytic activity responsible for the cleavage between p23 and p14 resides within p23. In order to determine the cleavage site between these two proteins, the respect...

  11. Scientific Opinion on the Role of Tick Vectors in the Epidemiology of Crimean-Congo Hemorrhagic Fever and African Swine Fever in Eurasia

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Animal Health and Welfare (AHAW

    2010-08-01

    Full Text Available The report provides an update on the role of the tick vectors in the epidemiology of African swine fever (ASF and Crimean and Congo haemorrhagic fever (CCHF in Eurasia, specifically to review of the geographical distribution of the relevant ticks with presentation of maps of their occurrence in Europe and Mediterranean basin; a description of the factors that define the relevant tick population dynamics and identify possible high risk areas in the EU; an update on the role of tick vectors associated with CCHF and ASF in Eurasia; and reviews available methods for the control of the relevant tick vectors. Data were collected through systematic literature review in a database from which maps of geographic distribution of ticks, CCHF virus and ASF virus were issued. The main vectors for CCHF are Hyalomma spp, Increase in the number of fragmented areas and the degradation of agricultural lands to bush lands are the two main factors in the creation of new foci of CCHF in endemic areas. Movement of livestock and wildlife species, which may carry infected ticks, contributes to the spread of the infection. The Middle East and Balkan countries are the most likely sources of introduction of CCHFV into other European countries. All the Ornithodoros species investigated so far can become infective with ASF virus and are perhaps biological vectors. These ticks are important in maintaining the local foci of the ASFV, but do not play an active role in the geographical spread of the virus. Wild boars have never been found infested by Ornithodoros spp. because wild boars normally do not rest inside protected burrows, but above the ground. There is no single ideal solution to the control of ticks relevant for CCHF or ASF. The integrated control approach is probably the most effective.

  12. Qualitative, quantitative and structural analysis of non- coding regions of classical swine fever virus genome

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Classical swine fever virus (CSFV) is the pathogen of the swine fever. Understanding of the replication and expression of its genome is the basis for research of the pathogenicity for CSFV and development of antiviral drug. The noncoding regions (NCRs) of CSFV are the main regulatory regions for replication and expression. Qualitative, quantitative and structural analysis of 3′ NCRs and 5′ NCRs was done in order to locate the regulatory region in the NCRs and to character the NCRs. The sites, conserved sequences and structural elements related to the initiation of replication and expression were extracted from 17 3′ NCRs and 56 5′ NCRs. Those cis-elements may be initial recognition sites for replication, binding sites for transcription factors of host cell and interacting sites for initiation of protein synthesis, based on which a mechanism for the replication and expression of CSFV was brought forth. This research offers the direction for further experiment and lays down a basis for the research on hepatitis C virus (HCV), other pestiviruses and plus-strand RNA viruses.

  13. Efficacy of a live attenuated vaccine in classical swine fever virus postnatally persistently infected pigs.

    Science.gov (United States)

    Muñoz-González, Sara; Perez-Simó, Marta; Muñoz, Marta; Bohorquez, José Alejandro; Rosell, Rosa; Summerfield, Artur; Domingo, Mariano; Ruggli, Nicolas; Ganges, Llilianne

    2015-01-01

    Classical swine fever (CSF) causes major losses in pig farming, with various degrees of disease severity. Efficient live attenuated vaccines against classical swine fever virus (CSFV) are used routinely in endemic countries. However, despite intensive vaccination programs in these areas for more than 20 years, CSF has not been eradicated. Molecular epidemiology studies in these regions suggests that the virus circulating in the field has evolved under the positive selection pressure exerted by the immune response to the vaccine, leading to new attenuated viral variants. Recent work by our group demonstrated that a high proportion of persistently infected piglets can be generated by early postnatal infection with low and moderately virulent CSFV strains. Here, we studied the immune response to a hog cholera lapinised virus vaccine (HCLV), C-strain, in six-week-old persistently infected pigs following post-natal infection. CSFV-negative pigs were vaccinated as controls. The humoral and interferon gamma responses as well as the CSFV RNA loads were monitored for 21 days post-vaccination. No vaccine viral RNA was detected in the serum samples and tonsils from CSFV postnatally persistently infected pigs for 21 days post-vaccination. Furthermore, no E2-specific antibody response or neutralising antibody titres were shown in CSFV persistently infected vaccinated animals. Likewise, no of IFN-gamma producing cell response against CSFV or PHA was observed. To our knowledge, this is the first report demonstrating the absence of a response to vaccination in CSFV persistently infected pigs. PMID:26159607

  14. 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 by...... reconstructing ancestral sequences. To test this hypothesis, we inferred sequences that correspond to ancestral nodes in a phylogenetic tree built from full-length nucleotide sequences of non-functional Koslov cDNAs and then proceeded to test the reconstructions. Specifically, we altered a non-functional cDNA by...... site directed mutagenesis, removing non-synonymous mutations step by step. In vitro testing of modified constructs did indeed lead to fully functional viruses with similar growth kinetics as the wild-type strain. Moreover, viruses rescued from the construct had the ancestral amino acid sequence and...

  15. Dynamic distribution and tissue tropism of classical swine fever virus in experimentally infected pigs

    Directory of Open Access Journals (Sweden)

    Tang Bo

    2011-05-01

    Full Text Available Abstract Background Classical swine fever (CSF, caused by the Classical swine fever virus (CSFV, is an Office International des Epizooties (OIE notifiable disease. However, we are far from fully understand the distribution, tissue tropism, pathogenesis, replication and excretion of CSFV in pigs. In this report, we investigated the dynamic distribution and tissue tropism of the virus in internal organs of the experimentally infected pigs using real-time RT-PCR and immunohistochemistry (IHC. Results A relative quantification real-time PCR was established and used to detect the virus load in internal organs of the experimentally infected pigs. The study revealed that the virus was detected in all 21 of the internal organs and blood collected from pigs at day 1 to day 8 post infections, and had an increasing virus load from day 1 to day 8 post infections. However, there was irregular distribution virus load in most internal organs over the first 2 days post infection. Blood, lymphoid tissue, pancreas and ileum usually contain the highest viral loads, while heart, duodenum and brain show relatively low viral loads. Conclusions All the data suggest that CSFV had an increasing virus load from day 1 to day 8 post infections in experimentally infected pigs detected by real-time RT-PCR, which was in consistent with the result of the IHC staining. The data also show that CSFV was likely to reproduce in blood, lymphoid tissue, pancreas and the ileum, while unlikely to replicate in the heart, duodenum and brain. The results provide a foundation for further clarification of the pathogenic mechanism of CSFV in internal organs, and indicate that blood, lymphoid tissue, pancreas and ileum may be preferred sites of acute infection.

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

    Directory of Open Access Journals (Sweden)

    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.

  17. Rapid Detection of Classical Swine Fever Virus by a Portable Real-Time Reverse Transcriptase PCR Assay

    OpenAIRE

    Risatti, G. R.; Callahan, J. D.; Nelson, W. M.; Borca, M. V.

    2003-01-01

    A fluorogenic-probe hydrolysis (TaqMan)-reverse transcriptase PCR assay for classical swine fever virus (CSFV) was developed and evaluated in experimentally infected swine. The assay detected CSFV, representing different phylogenetic groupings, but did not amplify viral RNA from related pestiviruses. The assay met or exceeded the sensitivity (1 to 100 50% tissue culture infective doses per ml) of viral cultures of samples from experimentally infected animals. Viral RNA was detected in nasal a...

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

    DEFF Research Database (Denmark)

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

    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...... the control of the wt or mutant CSFV IRES and transfected into BHK cells infected with vTF7-3 which expresses the T7 RNA polymerase. rLuc activity was measured in cell lysates. A series of IRES mutants representing different levels of IRES activity (20% - 100%) were selected and inserted by homologous...

  19. PKR activation enhances replication of classical swine fever virus in PK-15 cells.

    Science.gov (United States)

    Liu, Wen-Jun; Yang, You-Tian; Zhao, Ming-Qiu; Dong, Xiao-Ying; Gou, Hong-Chao; Pei, Jing-Jing; Chen, Jin-Ding

    2015-06-01

    Classical swine fever (CSF) is a highly contagious swine disease that is responsible for economic losses worldwide. Protein kinase R (PK)R is an important protein in the host viral response; however, the role of PKR in CSFV infection remains unknown. This issue was addressed in the present study using the PK-15 swine kidney cell line. We found that CSFV infection increased the phosphorylation of eukaryotic translation initiation factor (eIF)2α and its kinase PKR. However, the expression of viral proteins continued to increase. Furthermore, PKR overexpression enhanced CSFV replication, while PKR inhibition resulted in reduced CSFV replication and an increase in interferon (IFN) induction. In addition, PKR was responsible for eIF2α phosphorylation in CSFV-infected cells. These results suggest that the activation of PKR during CSFV infection is beneficial to the virus. The virus is able to commandeer the host cell's translation machinery for viral protein synthesis while evading innate immune defenses. PMID:25899421

  20. Establishment and characterization of a chimeric infectious cDNA clone of classical swine fever virus.

    Science.gov (United States)

    Zhao, T S; Xia, Y H

    2016-01-01

    Classical swine fever virus (CSFV) causes a highly contagious disease among swine that has an important economic impact worldwide. There are two important CSFV strains in China, Shimen and hog cholera lapinized virus (HCLV). Shimen strain is highly virulent while HCLV, also referred to as C-strain, is a live attenuated vaccine strain considered to be one of the most effective and safest live vaccines. In this study, a chimeric infectious cDNA clone of CSFV named pT7SM-c was engineered by replacing the Erns genomic region of an infectious clone of CSFV Shimen strain, pT7SM, with the same region obtained from HCLV. RNA transcripts of pT7SM-c containing an engineered EcoRI site that served as a genetic marker were directly infectious in PK15 cells. The rescued virus vT7SM-c showed similar growth kinetics and cytopathic effect with the parental virus vT7SM in the cells. The chimeric infectious cDNA clone can be used as a practical tool for further studying of the virulence, protein function and pathogenesis of CSFV through genetic manipulation. PMID:27265471

  1. Classical Swine Fever Virus vs. Classical Swine Fever Virus: The Superinfection Exclusion Phenomenon in Experimentally Infected Wild Boar

    Science.gov (United States)

    Muñoz-González, Sara; Pérez-Simó, Marta; Colom-Cadena, Andreu; Cabezón, Oscar; Bohórquez, José Alejandro; Rosell, Rosa; Pérez, Lester Josué; Marco, Ignasi; Lavín, Santiago; Domingo, Mariano; Ganges, Llilianne

    2016-01-01

    Two groups with three wild boars each were used: Group A (animals 1 to 3) served as the control, and Group B (animals 4 to 6) was postnatally persistently infected with the Cat01 strain of CSFV (primary virus). The animals, six weeks old and clinically healthy, were inoculated with the virulent strain Margarita (secondary virus). For exclusive detection of the Margarita strain, a specific qRT-PCR assay was designed, which proved not to have cross-reactivity with the Cat01 strain. The wild boars persistently infected with CSFV were protected from superinfection by the virulent CSFV Margarita strain, as evidenced by the absence of clinical signs and the absence of Margarita RNA detection in serum, swabs and tissue samples. Additionally, in PBMCs, a well-known target for CSFV viral replication, only the primary infecting virus RNA (Cat01 strain) could be detected, even after the isolation in ST cells, demonstrating SIE at the tissue level in vivo. Furthermore, the data analysis of the Margarita qRT-PCR, by means of calculated ΔCt values, supported that PBMCs from persistently infected animals were substantially protected from superinfection after in vitro inoculation with the Margarita virus strain, while this virus was able to infect naive PBMCs efficiently. In parallel, IFN-α values were undetectable in the sera from animals in Group B after inoculation with the CSFV Margarita strain. Furthermore, these animals were unable to elicit adaptive humoral (no E2-specific or neutralising antibodies) or cellular immune responses (in terms of IFN-γ-producing cells) after inoculation with the second virus. Finally, a sequence analysis could not detect CSFV Margarita RNA in the samples tested from Group B. Our results suggested that the SIE phenomenon might be involved in the evolution and phylogeny of the virus, as well as in CSFV control by vaccination. To the best of our knowledge, this study was one of the first showing efficient suppression of superinfection in animals

  2. Classical Swine Fever Virus vs. Classical Swine Fever Virus: The Superinfection Exclusion Phenomenon in Experimentally Infected Wild Boar.

    Science.gov (United States)

    Muñoz-González, Sara; Pérez-Simó, Marta; Colom-Cadena, Andreu; Cabezón, Oscar; Bohórquez, José Alejandro; Rosell, Rosa; Pérez, Lester Josué; Marco, Ignasi; Lavín, Santiago; Domingo, Mariano; Ganges, Llilianne

    2016-01-01

    Two groups with three wild boars each were used: Group A (animals 1 to 3) served as the control, and Group B (animals 4 to 6) was postnatally persistently infected with the Cat01 strain of CSFV (primary virus). The animals, six weeks old and clinically healthy, were inoculated with the virulent strain Margarita (secondary virus). For exclusive detection of the Margarita strain, a specific qRT-PCR assay was designed, which proved not to have cross-reactivity with the Cat01 strain. The wild boars persistently infected with CSFV were protected from superinfection by the virulent CSFV Margarita strain, as evidenced by the absence of clinical signs and the absence of Margarita RNA detection in serum, swabs and tissue samples. Additionally, in PBMCs, a well-known target for CSFV viral replication, only the primary infecting virus RNA (Cat01 strain) could be detected, even after the isolation in ST cells, demonstrating SIE at the tissue level in vivo. Furthermore, the data analysis of the Margarita qRT-PCR, by means of calculated ΔCt values, supported that PBMCs from persistently infected animals were substantially protected from superinfection after in vitro inoculation with the Margarita virus strain, while this virus was able to infect naive PBMCs efficiently. In parallel, IFN-α values were undetectable in the sera from animals in Group B after inoculation with the CSFV Margarita strain. Furthermore, these animals were unable to elicit adaptive humoral (no E2-specific or neutralising antibodies) or cellular immune responses (in terms of IFN-γ-producing cells) after inoculation with the second virus. Finally, a sequence analysis could not detect CSFV Margarita RNA in the samples tested from Group B. Our results suggested that the SIE phenomenon might be involved in the evolution and phylogeny of the virus, as well as in CSFV control by vaccination. To the best of our knowledge, this study was one of the first showing efficient suppression of superinfection in animals

  3. Classical Swine Fever Virus vs. Classical Swine Fever Virus: The Superinfection Exclusion Phenomenon in Experimentally Infected Wild Boar.

    Directory of Open Access Journals (Sweden)

    Sara Muñoz-González

    Full Text Available Two groups with three wild boars each were used: Group A (animals 1 to 3 served as the control, and Group B (animals 4 to 6 was postnatally persistently infected with the Cat01 strain of CSFV (primary virus. The animals, six weeks old and clinically healthy, were inoculated with the virulent strain Margarita (secondary virus. For exclusive detection of the Margarita strain, a specific qRT-PCR assay was designed, which proved not to have cross-reactivity with the Cat01 strain. The wild boars persistently infected with CSFV were protected from superinfection by the virulent CSFV Margarita strain, as evidenced by the absence of clinical signs and the absence of Margarita RNA detection in serum, swabs and tissue samples. Additionally, in PBMCs, a well-known target for CSFV viral replication, only the primary infecting virus RNA (Cat01 strain could be detected, even after the isolation in ST cells, demonstrating SIE at the tissue level in vivo. Furthermore, the data analysis of the Margarita qRT-PCR, by means of calculated ΔCt values, supported that PBMCs from persistently infected animals were substantially protected from superinfection after in vitro inoculation with the Margarita virus strain, while this virus was able to infect naive PBMCs efficiently. In parallel, IFN-α values were undetectable in the sera from animals in Group B after inoculation with the CSFV Margarita strain. Furthermore, these animals were unable to elicit adaptive humoral (no E2-specific or neutralising antibodies or cellular immune responses (in terms of IFN-γ-producing cells after inoculation with the second virus. Finally, a sequence analysis could not detect CSFV Margarita RNA in the samples tested from Group B. Our results suggested that the SIE phenomenon might be involved in the evolution and phylogeny of the virus, as well as in CSFV control by vaccination. To the best of our knowledge, this study was one of the first showing efficient suppression of

  4. Genetic diversity of subgenotype 2.1 isolates of classical swine fever virus.

    Science.gov (United States)

    Gong, Wenjie; Wu, Jianmin; Lu, Zongji; Zhang, Li; Qin, Shaomin; Chen, Fenglian; Peng, Zhicheng; Wang, Qin; Ma, Ling; Bai, Anbin; Guo, Huancheng; Shi, Jishu; Tu, Changchun

    2016-07-01

    As the causative agent of classical swine fever, the economically devastating swine disease worldwide, classical swine fever virus (CSFV) is currently classified into the 11 subgenotypes, of which subgenotype 2.1 is distributed worldwide and showing more genetic diversity than other subgenotypes. Prior to this report, subgenotype 2.1 was divided into three sub-subgenotypes (2.1a-2.1c). To further analyze the genetic diversity of CSFV isolates in China, 39 CSFV isolates collected between 2004 and 2012 in two Chinese provinces Guangxi and Guangdong were sequenced and subjected to phylogenetic analysis together with reference sequences retrieved from GenBank. Phylogenetic analyses based on the 190-nt and/or 1119-nt full length E2 gene fragments showed that current CSFV subgenotype 2.1 virus isolates in the world could be divided into 10 sub-subgenotypes (2.1a-2.1j) and the 39 isolates collected in this study were grouped into 7 of them (2.1a-2.1c and 2.1g-2.1j). Among the 10 sub-subgenotypes, 2.1d-2.1j were newly identified. Sub-subgenotype 2.1d isolates were circulated only in India, however the rest 9 sub-subgenotypes were from China with some of them closely related to isolates from European and neighboring Asian countries. According to the temporal and spatial distribution of CSFV subgenotype 2.1 isolates, the newly classified 10 sub-subgenotypes were further categorized into three groups: dominant sub-subgenotype, minor sub-subgenotype and silent sub-subgenotype, and each sub-subgenotype can be found only in certain geographical areas. Taken together, this study reveals the complex genetic diversity of CSFV subgenotype 2.1 and improves our understanding about the epidemiological trends of CSFV subgenotype 2.1 in the world, particularly in China. PMID:27085291

  5. Complete Genome Sequence Analysis of Acute and Mild Strains of Classical Swine Fever Virus Subgenotype 3.2.

    Science.gov (United States)

    Lim, Seong-In; Han, Song-Hee; Hyun, HyeSook; Lim, Ji-Ae; Song, Jae-Young; Cho, In-Soo; An, Dong-Jun

    2016-01-01

    We report the complete genome sequences of two classical swine fever virus strains (JJ9811 and YI9908). Both belong to subgenotype 3.2. Strain JJ9811 causes mild symptoms and strain YI9908 causes acute symptoms. The sequences were 95.7% homologous at the nucleotide level and 95.6% homologous at the amino acid level. PMID:26823570

  6. Complete Genome Sequence Analysis of Acute and Mild Strains of Classical Swine Fever Virus Subgenotype 3.2

    OpenAIRE

    Lim, Seong-In; Han, Song-Hee; Hyun, HyeSook; Lim, Ji-Ae; SONG, Jae-Young; Cho, In-Soo; An, Dong-Jun

    2016-01-01

    We report the complete genome sequences of two classical swine fever virus strains (JJ9811 and YI9908). Both belong to subgenotype 3.2. Strain JJ9811 causes mild symptoms and strain YI9908 causes acute symptoms. The sequences were 95.7% homologous at the nucleotide level and 95.6% homologous at the amino acid level.

  7. Mutations in the Carboxyl Terminal Region of E2 Glycoprotein of Classical Swine Fever Virus are Responsible for Viral Attenuation in Swine

    Science.gov (United States)

    We have previously reported that combining specific genetic information from the Classical Swine Fever Virus (CSFV) vaccine strain CS with that of virulent CSFV strain Brescia (BICv) resulted in disease attenuation for pigs. To identify the specific amino acids mediate attenuation, a series of chime...

  8. 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

    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...... 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...

  9. Time-calibrated phylogenomics of the classical swine fever viruses: genome-wide bayesian coalescent approach.

    Directory of Open Access Journals (Sweden)

    Taehyung Kwon

    Full Text Available The phylogeny of classical swine fever virus (CSFV, the causative agent of classical swine fever (CSF, has been investigated extensively. However, no evolutionary research has been performed using the whole CSFV genome. In this study, we used 37 published genome sequences to investigate the time-calibrated phylogenomics of CSFV. In phylogenomic trees based on Bayesian inference (BI and Maximum likelihood (ML, the 37 isolates were categorized into five genetic types (1.1, 1.2, 2.1, 2.3, and 3.4. Subgenotype 1.1 is divided into 3 groups and 1 unclassified isolate, 2.1 into 4 groups, 2.3 into 2 groups and 1 unclassified isolate, and subgenotype 1.2 and 3.4 consisted of one isolate each. We did not observe an apparent temporal or geographical relationship between isolates. Of the 14 genomic regions, NS4B showed the most powerful phylogenetic signal. Results of this evolutionary study using Bayesian coalescent approach indicate that CSFV has evolved at a rate of 13×.010-4 substitutions per site per year. The most recent common ancestor of CSFV appeared 2770.2 years ago, which was about 8000 years after pig domestication. The effective population size of CSFV underwent a slow increase until the 1950s, after which it has remained constant.

  10. Time-calibrated phylogenomics of the classical swine fever viruses: genome-wide bayesian coalescent approach.

    Science.gov (United States)

    Kwon, Taehyung; Yoon, Sook Hee; Kim, Kyu-Won; Caetano-Anolles, Kelsey; Cho, Seoae; Kim, Heebal

    2015-01-01

    The phylogeny of classical swine fever virus (CSFV), the causative agent of classical swine fever (CSF), has been investigated extensively. However, no evolutionary research has been performed using the whole CSFV genome. In this study, we used 37 published genome sequences to investigate the time-calibrated phylogenomics of CSFV. In phylogenomic trees based on Bayesian inference (BI) and Maximum likelihood (ML), the 37 isolates were categorized into five genetic types (1.1, 1.2, 2.1, 2.3, and 3.4). Subgenotype 1.1 is divided into 3 groups and 1 unclassified isolate, 2.1 into 4 groups, 2.3 into 2 groups and 1 unclassified isolate, and subgenotype 1.2 and 3.4 consisted of one isolate each. We did not observe an apparent temporal or geographical relationship between isolates. Of the 14 genomic regions, NS4B showed the most powerful phylogenetic signal. Results of this evolutionary study using Bayesian coalescent approach indicate that CSFV has evolved at a rate of 13×.010-4 substitutions per site per year. The most recent common ancestor of CSFV appeared 2770.2 years ago, which was about 8000 years after pig domestication. The effective population size of CSFV underwent a slow increase until the 1950s, after which it has remained constant. PMID:25815768

  11. Biological and molecular characterization of classical swine fever challenge virus from India

    Directory of Open Access Journals (Sweden)

    Parveen Kumar

    2015-03-01

    Full Text Available Aim: The aim of this study was biological and molecular characterization of classical swine fever (CSF challenge virus from India. Materials and Methods: CSF challenge virus maintained at Division of Biological standardization was experimentally infected to two seronegative piglets. The biological characterization was done by clinical sign and symptoms along with postmortem findings. For molecular characterization 5’-nontranslated region, E2 and NS5B regions were amplified by reverse transcription polymerase chain reaction and sequenced. The sequences were compared with that of reference strains and the local field isolates to establish a phylogenetic relation. Results: The virus produced symptoms of acute disease in the piglets with typical post-mortem lesions. Phylogenetic analysis of the three regions showed that the current Indian CSF Challenge virus is having maximum similarity with the BresciaX strain (USA and Madhya Pradesh isolate (India and is belonging to subgroup 1.2 under Group 1. Conclusion: Based on biological and molecular characterization of CSF challenge virus from India is described as a highly virulent virus belonging to subgroup 1.2 under Group 1 along with some field isolates from India and Brescia strain.

  12. Rapid Recovery of Classical Swine Fever Virus Directly from Cloned cDNA

    Institute of Scientific and Technical Information of China (English)

    HUANG Jun-hua; LI Yong-feng; HE Fan; LI Dan; SUN Yuan; HAN Wen; QIU Hua-ji

    2013-01-01

    The reverse genetics for classical swine fever virus (CSFV) is currently based on the transfection of in vitro transcribed RNA from a viral genomic cDNA clone, which is inefficient and time-consuming. This study was aimed to develop an improved method for rapid recovery of CSFV directly from cloned cDNA. Full-length genomic cDNA from the CSFV Shimen strain, which was flanked by a T7 promoter, the hepatitis delta virus ribozyme and T7 terminator sequences, was cloned into the low-copy vector pOK12, producing pOKShimen-RzT . Direct transfection of pOKShimen-RzT into PK/T7 cells, a PK-15-derived cell line stably expressing bacteriophage T7 RNA polymerase, allowed CSFV to be rescued rapidly and efficiently, i.e., at least 12 h faster and 31.6-fold greater viral titer when compared with the in vitro transcription-based rescue system. Furthermore, the progeny virus rescued from PK/T7 cells was indistinguishable, both in vitro and in vivo, from its parent virus and the virus rescued from classical reverse genetics. The reverse genetics based on intracellular transcription is efficient, convenient and cost-effective. The PK/T7 cell line can be used to rescue CSFV directly from cloned cDNA and it can also be used as an intracellular transcription and expression system for studying the structure and function of viral genes.

  13. Generation and evaluation of a chimeric classical swine fever virus expressing a visible marker gene.

    Science.gov (United States)

    Li, Yongfeng; Wang, Xiao; Sun, Yuan; Li, Lian-Feng; Zhang, Lingkai; Li, Su; Luo, Yuzi; Qiu, Hua-Ji

    2016-03-01

    Classical swine fever virus (CSFV) is a noncytopathogenic virus, and the incorporation of an enhanced green fluorescent protein (EGFP) tag into the viral genome provides a means of direct monitoring of viral infection without immunostaining. It is well established that the 3' untranslated region (3'-UTR) of the CSFV plays an important role in viral RNA replication. Although CSFV carrying a reporter gene and chimeric CSFV have been generated and evaluated, a chimeric CSFV with a visible marker has not yet been reported. Here, we generated and evaluated a chimeric virus containing the EGFP tag and the 3'-UTR from vaccine strain HCLV (C-strain) in the genetic background of the highly virulent CSFV Shimen strain. The chimeric marker CSFV was fluorescent and had an approximately 100-fold lower viral titer, lower replication level of viral genome, and weaker fluorescence intensity than the recombinant CSFV with only the EGFP tag or the parental virus. Furthermore, the marker chimera was avirulent and displayed no viremia in inoculated pigs, which were completely protected from lethal CSFV challenge as early as 15 days post-inoculation. The chimeric marker virus was visible in vitro and attenuated in vitro and in vivo, which suggests that CSFV can be engineered to produce attenuated variants with a visible marker to facilitate in vitro studies of CSFV infection and replication and to develop of novel vaccines against CSF. PMID:26614259

  14. [Research Progress in the Core Proteins of the Classical Swine Fever Virus].

    Science.gov (United States)

    Hou, Yuzhen; Zhao, Dantong; Liu, Guoying; He, Fan; Liu, Bin; Fu, Shaoyin; Hao, Yongqing; Zhang, Wenguang

    2015-09-01

    The core protein (CP) of the classical swine fever virus (CSFV) is one of its structural proteins. Apart from forming the nucleocapsid to protect internal viral genomic RNA, this protein is involved in transcriptional regulation. Also, during viral infection, the CP is involved in interactions with many host proteins. In this review, we combine study of this protein with its disorders, structural/functional characteristics, as well as its interactions with the non-structural proteins NS3, NS5B and host proteins such as SUMO-1, UBC9, OS9 and IQGAP1. We also summarize the important part played by the CP in CSFV pathogenicity, virulence and replication of genomic RNA. We also provide guidelines for further studies in the CP of the CSFV. PMID:26738299

  15. A new subgenotype 2.1d isolates of classical swine fever virus in China, 2014.

    Science.gov (United States)

    Zhang, Hongliang; Leng, Chaoliang; Feng, Liping; Zhai, Hongyue; Chen, Jiazeng; Liu, Chunxiao; Bai, Yun; Ye, Chao; Peng, Jinmei; An, Tongqing; Kan, Yunchao; Cai, Xuehui; Tian, Zhijun; Tong, Guangzhi

    2015-08-01

    The lapinized attenuated vaccine against classical swine fever (CSF) has been used in China for over half a century and has generally prevented large-scale outbreaks in recent years. However, since late 2014, a large number of new cases of CSF were detected in many immunized pig farms in China. Several of these CSV viruses were isolated and characterized. Phylogenetic and genomic sequence analyses indicate that these new isolates, as well as some reference isolates, form a new subgenotype named 2.1d, and share several consistent molecular characteristics. Since these new isolates emerged in disparate geographic regions within 5 months, this suggests that these isolates may be widespread. Given that current vaccines do not appear to provide effective protection against this new subgenotype, further investigation of these strains is urgently needed. PMID:26031602

  16. Genotyping of classical swine fever virus using high-resolution melt analysis.

    Science.gov (United States)

    Titov, Ilya; Tsybanov, Sodnom; Malogolovkin, Alexander

    2015-11-01

    Discrimination between different field and vaccine strains of classical swine fever virus (CSFV) is crucial for meaningful disease diagnosis and epidemiological investigation. In this study, a rapid method for differentiating vaccine strains and outbreak CSFV isolates by combined RT-PCR and high-resolution melt (HRM) analysis has been developed. The assay is based on PCR amplification of short fragments from the most variable region of CSFVgene E2, followed by HRM analysis of amplicons. Real-Time PCR/HRM for CSFV detection and differentiation analysis has sensitivity comparable to RT-qPCR and genotyping resolution comparable to E2 nucleotide sequencing. This assay in one step enables rapid and sensitive identification and genotype discrimination of CSFV in field samples, and thus will be valuable for CSF outbreak response and disease control. PMID:26300371

  17. RNA interference screening of interferon-stimulated genes with antiviral activities against classical swine fever virus using a reporter virus.

    Science.gov (United States)

    Wang, Xiao; Li, Yongfeng; Li, Lian-Feng; Shen, Liang; Zhang, Lingkai; Yu, Jiahui; Luo, Yuzi; Sun, Yuan; Li, Su; Qiu, Hua-Ji

    2016-04-01

    Classical swine fever (CSF) caused by classical swine fever virus (CSFV) is a highly contagious and often fatal disease of pigs, which leads to significant economic losses in many countries. Viral infection can induce the production of interferons (IFNs), giving rise to the transcription of hundreds of IFN-stimulated genes (ISGs) to exert antiviral effects. Although numerous ISGs have been identified to possess antiviral activities against different viruses, rare anti-CSFV ISGs have been reported to date. In this study, to screen anti-CSFV ISGs, twenty-one ISGs reported previously were individually knocked down using small interfering RNAs (siRNAs) followed by infection with a reporter CSFV expressing Renilla luciferase (Rluc). As a result, four novel anti-CSFV ISGs were identified, including natural-resistance-associated macrophage protein 1 (NRAMP1), cytosolic 5'-nucleotidase III A (NT5C3A), chemokine C-X-C motif ligand 10 (CXCL10), and 2'-5'-oligoadenylate synthetase 1 (OAS1), which were further verified to exhibit antiviral activities against wild-type CSFV. We conclude that the reporter virus is a useful tool for efficient screening anti-CSFV ISGs. PMID:26868874

  18. Viral hemorrhagic fevers of animals caused by DNA viruses

    Science.gov (United States)

    Here we outline serious diseases of food and fiber animals that cause damaging economic effect on products all over the world. The only vector-borne DNA virus is included here, such as African swine fever virus, and the herpes viruses discussed have a complex epidemiology characterized by outbreak...

  19. Dynamics of virus excretion via different routes in pigs experimentally infected with classical swine fever virus strains of high, moderate or low virulence

    OpenAIRE

    Weesendorp, Eefke; Stegeman, Arjan; Loeffen, Willie

    2008-01-01

    Dynamics of virus excretion via different routes in pigs experimentally infected with classical swine fever virus strains of high, moderate or low virulence NETHERLANDS (Weesendorp, Eefke) NETHERLANDS Received: 2008-04-07 Revised: 2008-05-28 Accepted: 2008-06-06

  20. Hypervariable antigenic region 1 of classical swine fever virus E2 protein impacts antibody neutralization.

    Science.gov (United States)

    Liao, Xun; Wang, Zuohuan; Cao, Tong; Tong, Chao; Geng, Shichao; Gu, Yuanxing; Zhou, Yingshan; Li, Xiaoliang; Fang, Weihuan

    2016-07-19

    Envelope glycoprotein E2 of classical swine fever virus (CSFV) is the major antigen that induces neutralizing antibodies and confers protection against CSFV infection. There are three hypervariable antigenic regions (HAR1, HAR2 and HAR3) of E2 that are different between the group 1 vaccine C-strain and group 2 clinical isolates. This study was aimed to characterize the antigenic epitope region recognized by monoclonal antibody 4F4 (mAb-4F4) that is present in the group 2 field isolate HZ1-08, but not in the C-strain, and examine its impact on neutralization titers when antisera from different recombinant viruses were cross-examined. Indirect ELISA with C-strain E2-based chimeric proteins carrying the three HAR regions showed that the mAb-4F4 bound to HAR1 from HZ1-08 E2, but not to HAR2 or HAR3, indicating that the specific epitope is located in the HAR1 region. Of the 6 major residues differences between C-strain and field isolates, Glu713 in the HAR1 region of strain HZ1-08 is critical for mAb-4F4 binding either at the recombinant protein level or using intact recombinant viruses carrying single mutations. C-strain-based recombinant viruses carrying the most antigenic part of E2 or HAR1 from strain HZ1-08 remained non-pathogenic to pigs and induced good antibody responses. By cross-neutralization assay, we observed that the anti-C-strain serum lost most of its neutralization capacity to RecC-HZ-E2 and QZ-14 (subgroup 2.1d field isolate in 2014), and vice versa. More importantly, the RecC-HAR1 virus remained competent in neutralizing ReC-HZ-E2 and QZ-14 strains without compromising the neutralization capability to the recombinant C-strain. Thus, we propose that chimeric C-strain carrying the HAR1 region of field isolates is a good vaccine candidate for classical swine fever. PMID:27317266

  1. Complete Genome Sequence of a Classical Swine Fever Virus Isolate Belonging to New Subgenotype 2.1d from Henan Province, Central China.

    Science.gov (United States)

    Lv, Chaochao; Yang, Qingyuan; Gao, Xiaojing; Yao, Yali; Li, Xiangdong; Xiao, Yan; Tian, Kegong

    2016-01-01

    We report here the complete genome sequence of HeN1505, a field isolate of classical swine fever virus belonging to the new subgenotype 2.1d. HeN1505 distinguishes itself from other classical swine fever virus (CSFVs) by 1 amino acid substitution in position 159 (threonine by isoleucine), which led to the loss of one N-glycosylation site in the N(pro) protein. PMID:27174260

  2. Complete Genome Sequence of a Classical Swine Fever Virus Isolate Belonging to New Subgenotype 2.1d from Henan Province, Central China

    OpenAIRE

    Lv, Chaochao; Yang, Qingyuan; Gao, Xiaojing; Yao, Yali; Li, Xiangdong; Xiao, Yan; Tian, Kegong

    2016-01-01

    We report here the complete genome sequence of HeN1505, a field isolate of classical swine fever virus belonging to the new subgenotype 2.1d. HeN1505 distinguishes itself from other classical swine fever virus (CSFVs) by 1 amino acid substitution in position 159 (threonine by isoleucine), which led to the loss of one N-glycosylation site in the Npro protein.

  3. Thirty-Five-Year Presence of African Swine Fever in Sardinia: History, Evolution and Risk Factors for Disease Maintenance.

    Science.gov (United States)

    Mur, L; Atzeni, M; Martínez-López, B; Feliziani, F; Rolesu, S; Sanchez-Vizcaino, J M

    2016-04-01

    Despite the implementation of control efforts and funds to fight against the disease, African swine fever (ASF) has been present in Sardinia since 1978. It has caused serious problems for both the industrial pig sector and the regional authorities in Sardinia, as well as the economy of Italy and the European Union, which annually supports the costly eradication programme. During this time, ASF has persisted, especially in the central-east part of Sardinia where almost 75% of the total outbreaks are concentrated. The Sardinian pig sector is clearly divided into two categories based on the specialization and industrialization of production: industrial farms, which represents only 1.8% of the farms in the island and non-professional holdings, which are comprised of small producers (90% of pig holdings have practices (e.g., use of communal areas) are likely the primary reasons for endemic persistence of the virus in this area. The compensation provided to the farmers, and other aspects of the eradication programme have also negatively influenced eradication efforts, indicating that socio-cultural and economic factors play an important role in the epidemiology of ASF on the island. The aim of this study was to comprehensively review the evolution of the 35-year presence of ASF in Sardinia, including control measures, and the environmental and socio-economic factors that may have contributed to disease endemicity on the island. The present review highlights the need for a coordinated programme that considers these socio-economic and environmental factors and includes an assessment of new cost-effective control strategies and diagnostic tools for effectively controlling ASF in Sardinia. PMID:25212957

  4. Molecular typing and phylogenetic analysis of classical swine fever virus isolates from Kerala, India.

    Science.gov (United States)

    Bhaskar, Nimisha; Ravishankar, Chintu; Rajasekhar, R; Sumod, K; Sumithra, T G; John, Koshy; Mini, M; Ravindran, Reghu; Shaji, Shiju; Aishwarya, J

    2015-12-01

    Classical swine fever (CSF) is an economically important disease of pigs caused by CSF virus (CSFV) belonging to the genus Pestivirus within the family Flaviviridae. The disease is endemic in many countries including India. A comprehensive study was carried out to assess the type of CSFV circulating in the South Indian state of Kerala. During the period 2013-2014, clinical samples were collected from 19 suspected CSF outbreaks of domestic pigs in different districts of Kerala. The samples were tested using nested reverse transcription PCR (RT-PCR) targeting the E2 gene and RT-PCR for 5'UTR of the virus. Partial 5' UTR and E2 gene regions of six CSFV isolates were sequenced. Phylogenetic analysis revealed that all the CSFV isolates belonged to subgroup 2.2. The isolates showed close resemblance to the other CSFV isolates circulating in India. It was also observed that the CSFV viruses from Kannur district were distinct from those circulating in the other districts as evidenced by their divergence from other Kerala isolates in the phylogenetic tree. Close relationship was seen to the CSFV isolates from South East Asian countries. PMID:26645036

  5. Episodic adaptive diversification of classical swine fever virus RNA-dependent RNA polymerase NS5B.

    Science.gov (United States)

    Li, Yan; Yang, Zexiao

    2015-12-01

    Classical swine fever virus (CSFV) is the pathogen that causes a highly infectious disease of pigs and has led to disastrous losses to pig farms and related industries. The RNA-dependent RNA polymerase (RdRp) NS5B is a central component of the replicase complex (RC) in some single-stranded RNA viruses, including CSFV. On the basis of genetic variation, the CSFV RdRps could be clearly divided into 2 major groups and a minor group, which is consistent with the phylogenetic relationships and virulence diversification of the CSFV isolates. However, the adaptive signature underlying such an evolutionary profile of the polymerase and the virus is still an interesting open question. We analyzed the evolutionary trajectory of the CSFV RdRps over different timescales to evaluate the potential adaptation. We found that adaptive selection has driven the diversification of the RdRps between, but not within, CSFV major groups. Further, the major adaptive divergence-related sites are located in the surfaces relevant to the interaction with other component(s) of RC and the entrance and exit of the template-binding channel. These results might shed some light on the nature of the RdRp in virulence diversification of CSFV groups. PMID:26485449

  6. Porcine circovirus type 2 (PCV2) infection decreases the efficacy of an attenuated classical swine fever virus (CSFV) vaccine

    OpenAIRE

    Huang Yu-Liang; Pang Victor; Lin Chun-Ming; Tsai Yi-Chieh; Chia Mi-Yuan; Deng Ming-Chung; Chang Chia-Yi; Jeng Chian-Ren

    2011-01-01

    Abstract The Lapinized Philippines Coronel (LPC) vaccine, an attenuated strain of classical swine fever virus (CSFV), is an important tool for the prevention and control of CSFV infection and is widely and routinely used in most CSF endemic areas, including Taiwan. The aim of this study was to investigate whether PCV2 infection affects the efficacy of the LPC vaccine. Eighteen 6-week-old, cesarean-derived and colostrum-deprived (CDCD), crossbred pigs were randomly assigned to four groups. A t...

  7. 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 ▿

    OpenAIRE

    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...

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

    Science.gov (United States)

    Hsu, Wei-Li; Chen, Chung-Lun; Huang, Shi-Wei; Wu, Chia-Chen; Chen, I-Hsuan; Nadar, Muthukumar; Su, Yin-Peng; Tsai, Ching-Hsiu

    2014-01-01

    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. PMID:24533157

  9. 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.

  10. Clustering of classical swine fever virus isolates by codon pair bias

    Directory of Open Access Journals (Sweden)

    Leifer Immanuel

    2011-11-01

    Full Text Available Abstract Background The genetic code consists of non-random usage of synonymous codons for the same amino acids, termed codon bias or codon usage. Codon juxtaposition is also non-random, referred to as codon context bias or codon pair bias. The codon and codon pair bias vary among different organisms, as well as with viruses. Reasons for these differences are not completely understood. For classical swine fever virus (CSFV, it was suggested that the synonymous codon usage does not significantly influence virulence, but the relationship between variations in codon pair usage and CSFV virulence is unknown. Virulence can be related to the fitness of a virus: Differences in codon pair usage influence genome translation efficiency, which may in turn relate to the fitness of a virus. Accordingly, the potential of the codon pair bias for clustering CSFV isolates into classes of different virulence was investigated. Results The complete genomic sequences encoding the viral polyprotein of 52 different CSFV isolates were analyzed. This included 49 sequences from the GenBank database (NCBI and three newly sequenced genomes. The codon usage did not differ among isolates of different virulence or genotype. In contrast, a clustering of isolates based on their codon pair bias was observed, clearly discriminating highly virulent isolates and vaccine strains on one side from moderately virulent strains on the other side. However, phylogenetic trees based on the codon pair bias and on the primary nucleotide sequence resulted in a very similar genotype distribution. Conclusion Clustering of CSFV genomes based on their codon pair bias correlate with the genotype rather than with the virulence of the isolates.

  11. 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...

  12. 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

    Classical swine fever (CSF) has caused significant economic losses in industrialized pig production, and is still present in some European countries. Recent CSF outbreaks in Europe were mainly associated with strains of genogroup 2 (subgroup 2.3). Although there are extensive datasets regarding 2...

  13. 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. PMID:27110709

  14. 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

  15. Preliminary Evaluation of a Candidate Multi-Epitope-Vaccine Against the Classical Swine Fever Virus

    Institute of Scientific and Technical Information of China (English)

    YING Jian; DONG Xiaonan; CHEN Yinghua

    2008-01-01

    A multi-epitope-vaccine MEVABC consisting of two linear neutralizing determinants (BC1: aa693-716; A6: aa844-865) located on antigenic unit B/C and unit A of glycoprotein E2 was prepared to evaluate whether a combination strategy is effective in the design of peptide vaccines.After immunization,pig sera collected every one to two weeks were evaluated by enzyme linked immunosorbent assay.C-strain- induced anti-sera and hyper-immune sera cannot recognize overlapping peptides that cover the E2 N-terminus,while MEVABC is able to elicit high levels of peptide-specific antibody response.When compared with previously studied peptide vaccines PV-BC1 and PV-A6,the same dose of either component in the MEVABC increases the BC1- or A6-specific antibodies (to 1/3-1/2 of the levels of the separate vaccines).However,the synergy between the antibodies may make MEVABC much more potent.Moreover,anti-C-strain immunity pre-existing in pigs does not disturb the sequent MEVABC vaccination.Thus,MEVABC can be ad- ministrated to pigs which already possess anti-classical swine fever virus immunity.MEVABC is a promising candidate marker vaccine.

  16. In vitro infection with classical swine fever virus inhibits the transcription of immune response genes

    Directory of Open Access Journals (Sweden)

    Feng Li

    2012-08-01

    Full Text Available Abstract Background Classical swine fever virus (CSFV can evade the immune response and establish chronic infection under natural and experimental conditions. Some genes related to antigen processing and presentation and to cytokine regulation are known to be involved in this response, but the precise mechanism through which each gene responds to CSFV infection remains unclear. Results In this study, the amplification standard curve and corresponding linear regression equations for the genes SLA-2, TAP1, SLA-DR, Ii, CD40, CD80, CD86, IFN-α, and IFN-β were established successfully. Real-time RT-PCR was used to quantify the immune response gene transcription in PK-15 cells post CSFV infection. Results showed that: (1 immune response genes were generally down-regulated as a result of CSFV infection, and (2 the expression of SLA-2, SLA-DR, Ii and CD80 was significantly decreased (p Conclusion We conclude that in vitro infection with CSFV inhibits the transcription of host immune response genes. These findings may facilitate the development of effective strategies for controlling CSF.

  17. Experimental infection of Bama miniature pigs with a highly virulent classical swine fever virus

    Directory of Open Access Journals (Sweden)

    Zhang Zhuo

    2011-09-01

    Full Text Available Abstract Background Currently, larger domestic pigs are only animals widely used in vaccine evaluation and pathogenicity study of classical swine fever virus (CSFV. This study was aimed to create an alternative animal experimental infection model of CSFV. Results Twenty specific-pathogen-free Bama miniature pigs were randomly divided into two groups and rooms, infected and non-infected, and the pigs in the infected group were inoculated intramuscularly with 104, 105 or 106 TCID50 (median tissue culture infective dose CSFV Shimen strain (n = 5 × 3 or left uninoculated to serve as in-contact pigs (n = 3. The uninfected control pigs (n = 2 were housed in a separate room. Clinical signs, body temperature, viraemia, tissue antigen distribution, pathological changes and seroconversion were monitored. Clinical signs were observed as early as 2 days post-inoculation (dpi in all infected pigs (though mild in contact pigs, but not non-infected control pigs. All inoculated pigs showed viraemia by 6 dpi. The in-contact pigs showed lower levels of viraemia. At 10 dpi, seroconversion was noted in five of the 15 inoculated pigs. All inoculated or one in-contact pigs died by 15 dpi. Conclusions These results show that Bama miniature pigs support productive CSFV infection and display clinical signs and pathological changes consistent with CSFV infections observed in larger domestic pigs.

  18. Detection system based on magnetoelastic sensor for classical swine fever virus.

    Science.gov (United States)

    Guo, Xing; Gao, Shuang; Sang, Shengbo; Jian, Aoqun; Duan, Qianqian; Ji, Jianlong; Zhang, Wendong

    2016-08-15

    In this paper, a magnetoelastic (ME) sensing system for the detection of classical swine fever virus (CSFV) is presented. The detection system comprises a test paper and a measurement circuit. The test paper consists mainly of an ME biosensor to detect the CSFV. Based on the impedance analysis technique, the measurement circuit is designed to measure the resonance frequency of the ME biosensor. The anti-CSFV IgG is immobilized onto the ME sensor surface to form the ME biosensor through a physical absorption approach. The experimental results show that the shift in the resonance frequency of the ME biosensor increases with the augmentation of the CSFV concentration. The effectiveness of the combination between the anti-CSFV IgG and CSFV is confirmed by the scanning electron microscopy (SEM) images, the sandwich-based enzyme-linked immunosorbent assay (ELISA) analysis, the interference study and the reference biosensor test method. The resonance frequency shift is linearly proportional to the concentration in the range from 0 to 2.5μg/ml, and becomes sub-linear at higher concentrations. The ME biosensor for CSFV detection has a sensitivity of about 95Hz/μg·ml(-1), with a detection limit of 0.6μg/ml. PMID:27078750

  19. Safety of classical swine fever virus vaccine strain LOM in pregnant sows and their offspring.

    Science.gov (United States)

    Lim, Seong-In; Song, Jae-Young; Kim, Jaejo; Hyun, Bang-Hun; Kim, Ha-Young; Cho, In-Soo; Kim, Byounghan; Woo, Gye-Hyeong; Lee, Jung-Bok; An, Dong-Jun

    2016-04-12

    The present study aimed to evaluate the safety of the classical swine fever virus (CSFV) vaccine strain LOM in pregnant sows. Pregnant sows with free CSFV antibody were inoculated with a commercial LOM vaccine during early pregnancy (day 38; n=3) or mid-pregnancy (days 49-59; n=11). In pregnant sows vaccinated during the early stages of gestation, abortion (day 109) was observed in one case, with two stillbirths and seven mummified fetuses. The viability of live-born piglets was 34.9% in sows vaccinated during mid-pregnancy compared with 81.8% in the control group. Post-mortem examination of the organs of the sows and piglets did not reveal any pathological lesions caused by CSFV; however, CSFV RNA was detected in the organs of several vaccinated sows and their litters. The LOM strain was transmitted from sows with free CSFV antibody to their fetus, but did not appear to induce immune tolerance in the offspring from vaccinated pregnant sows. Side effects were not observed in pregnant sows with antibody to the LOM strain: transmission from sow to their litters and stillbirth or mummified fetuses. The LOM strain may induce sterile immunity and provide rapid, long-lasting, and complete protection against CSFV; however, it should be contraindicated in pregnant sows due to potential adverse effects in pregnant sows with free CSFV antibody. PMID:26947495

  20. A study report on phylogenetic analysis of Classical swine fever virus isolated in different parts of the World

    Directory of Open Access Journals (Sweden)

    Sandip Chakraborty

    Full Text Available Classical Swine Fever Virus (CSFV is the cause of an economically important and contagious disease in all age groups of pigs. Advances in molecular methods have facilitated genetic typing of this virus which is useful for classification, to trace patterns of virus spread and exposing the weaknesses in control strategies. Moreover, the genetic comparison of the isolates obtained from a series of outbreaks with known linkages can be used to validate and to interpret the genetic typing to determine the rate of virus mutation in the field. The CSF viruses are grouped into three groups under which there are ten subgroups. This review highlights the works on phylogenetic analysis carried out by different workers from time to time in different parts of the world including India to have better understanding of the diversified genogrouping of this virus. [Vet. World 2012; 5(7.000: 437-442

  1. FKBP8 interact with classical swine fever virus NS5A protein and promote virus RNA replication.

    Science.gov (United States)

    Li, Helin; Zhang, Chengcheng; Cui, Hongjie; Guo, Kangkang; Wang, Fang; Zhao, Tianyue; Liang, Wulong; Lv, Qizhuang; Zhang, Yanming

    2016-02-01

    The non-structural 5A (NS5A) protein of classical swine fever virus (CSFV) is proven to be involved in viral replication and can also modulate cellular signaling and host cellular responses via to its ability to interact with various cellular proteins. FKBP8 is also reported to promote virus replication. Here, we show that NS5A specifically interacts with FKBP8 through coimmunoprecipitation and GST-pulldown studies. Additionally, confocal microscopy study showed that NS5A and FKBP8 colocalized in the cytoplasm. Overexpression of FKBP8 via the eukaryotic expression plasmid pDsRED N1 significantly promoted viral RNA synthesis. The cells knockdown of FKBP8 by lentivirus-mediated shRNA markedly decreased the virus replication when infected with CSFV. These data suggest that FKBP8 plays a critical role in the viral life cycle, particularly during the virus RNA replication period. The investigation of FKBP8 protein functions may be beneficial for developing new strategies to treat CSFV infection. PMID:26748656

  2. Differential detection of classical swine fever virus challenge strains in C-strain vaccinated pigs

    OpenAIRE

    Everett, Helen E.; Crudgington, Bentley S; Sosan-Soulé, Olubukola; Crooke, Helen R.

    2014-01-01

    Background Control of classical swine fever (CSF) by vaccination ideally requires that field strain infection can be detected irrespective of the vaccination status of the herd. To inform on the usefulness of molecular tests compatible with genetic Differentiation of Infected from Vaccinated Animals (DIVA) principles when using live-attenuated vaccines, tonsil homogenates from a vaccination-challenge experiment were analyzed using a differential real-time qRT-PCR for the C-strain vaccine or r...

  3. 9 CFR 94.17 - Dry-cured pork products from regions where foot-and-mouth disease, rinderpest, African swine...

    Science.gov (United States)

    2010-01-01

    ... where foot-and-mouth disease, rinderpest, African swine fever, classical swine fever, or swine vesicular... RINDERPEST, FOOT-AND-MOUTH DISEASE, EXOTIC NEWCASTLE DISEASE, AFRICAN SWINE FEVER, CLASSICAL SWINE FEVER... § 94.17 Dry-cured pork products from regions where foot-and-mouth disease, rinderpest, African......

  4. In memoriam: Cristiana Patta, DVM, 1958-2012, Virologist and specialist in African swine fever and exotic animal diseases

    Directory of Open Access Journals (Sweden)

    Anon.

    2012-03-01

    Full Text Available The veterinary world is shocked and deeply saddened by the untimely death of Cristiana Patta, manager at Sardinia’s Istituto Zooprofilattico Sperimentale.Cristiana was a nationally and internationally acclaimed virologist, distinguished throughout her intense but all-too-brief life by her talent and professionalism. After studying microbiology and virology at the University of Sassari, specialising in microbiological and virological techniques, she began her career as a researcher in the viral animal diseases sector at the Istituto di Sassari. Her work included the main aspects of exotic animal diseases, from diagnosis to control, as well as the planning and management of eradication programmes for the principal infectious diseases (swine fever, brucellosis, tuberculosis and bluetongue under European Union surveillance.Her knowledge of swine fever – and particularly African swine fever – led her to become a national and international expert in the control of this disease. In this role, she became a member of the roster of experts of the Ministry of Health and the European Commission. She contributed to numerous European research projects and was an invited speaker at many scientific assemblies sponsored by international organisations such as the OIE, FAO and EU.Cristiana also provided an authoritative contribution to training activities promoted by the Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise ‘G. Caporale’ in Teramo in its capacity as OIE collaboration centre for veterinary training, epidemiology, food safety and animal welfare, offering her expertise in exotic livestock diseases. The Italian veterinary service and national and European reference centres all benefitted from her experience and knowledge, through training events organised by the Ministry of Health and the regional authorities. Her technical expertise was matched by her managerial skills, in particular in the clinical management of veterinary public

  5. Rescue of the highly virulent classical swine fever virus strain “Koslov” from cloned cDNA and first insights into genome variations relevant for virulence

    DEFF Research Database (Denmark)

    Fahnøe, Ulrik; Pedersen, Anders Gorm; Risager, Peter Christian;

    2014-01-01

    Classical swine fever virus (CSFV) strain “Koslov” is highly virulent with a mortality rate of up to 100% in pigs. In this study, we modified non-functional cDNAs generated from the blood of Koslov virus infected pigs bysite-directed mutagenesis, removing non-synonymous mutations step...

  6. Genome Sequence of Classical Swine Fever Virus Genotype 1.1 with a Genetic Marker of Attenuation Detected in a Continuous Porcine Cell Line

    OpenAIRE

    Tomar, N.; Gupta, A; Arya, R. S.; Somvanshi, R.; Sharma, V.; Saikumar, G.

    2015-01-01

    The complete genome sequencing and analysis of a classical swine fever virus (CSFV) detected in a porcine kidney cell line revealed a close relationship with genotype 1.1 viruses circulating in India and China. The presence of consecutive T insertions in the 3′ untranslated region (UTR), as seen in vaccine strains of CSFV, suggested some degree of attenuation.

  7. Spatio-temporal patterns and movement analysis of pigs from smallholder farms and implications for African swine fever spread, Limpopo province, South Africa

    OpenAIRE

    Folorunso O. Fasina; Mokoele, Japhta M; B. Tom Spencer; Leo A.M.L. van Leengoed; Yvette Bevis; Ingrid Booysen

    2015-01-01

    Infectious and zoonotic disease outbreaks have been linked to increasing volumes of legal and illegal trade. Spatio-temporal and trade network analyses have been used to evaluate the risks associated with these challenges elsewhere, but few details are available for the pig sector in South Africa. Regarding pig diseases, Limpopo province is important as the greater part of the province falls within the African swine fever control area. Emerging small-scale pig farmers in Limpopo perceived pig...

  8. 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. PMID:26684209

  9. Development of a novel single-step reverse genetics system for the generation of classical swine fever virus.

    Science.gov (United States)

    Li, Ling; Pang, Huining; Wu, Rui; Zhang, Yanwen; Tan, Yiluo; Pan, Zishu

    2016-07-01

    We describe an alternative reverse genetics system for generating classical swine fever virus (CSFV) based on swine RNA polymerase I promoter (pSPI)-mediated vRNA transcription. The recombinant plasmid pSPTI/SM harboring a full-length CSFV Shimen strain cDNA, flanked by a swine RNA polymerase I (pol I) promoter sequence at the 5' end and a murine pol I terminator sequence at the 3' end, was constructed. When the plasmid pSPTI/SM was introduced into PK-15 cells by transfection, an infectious CSFV with termini identical to those of the parental virus was generated directly. CSFV rescued from this reverse genetics system exhibited similar growth kinetics and plaque formation compared with the parental CSFV. When the novel reverse genetics system was used to generate the CSFV vaccine C-strain, infectious virus was detected in the supernatant of PK-15 cells transfected with the recombinant plasmid pSPTI/C. This novel reverse genetics system is a simple and efficient tool for the investigation of the structure and function of the viral genome, for molecular pathogenicity studies, and for the development of genetically engineered vaccines for CSFV. PMID:27068166

  10. Substitution of specific cysteine residues in E1 glycoprotein of classical swine fever virus strain Brescia affects formation of E1-E2 heterodimers and alters virulence in swine

    Science.gov (United States)

    E1, along with E^rns and E2, is one of the three envelope glycoproteins of Classical Swine Fever Virus (CSFV). E1 and E2 are anchored to the virus envelope at their carboxyl termini and E^rns loosely associates with the viral envelope. In infected cells, E2 forms homodimers and heterodimers with E1,...

  11. The Lapinized Chinese Strain Vaccine Against Classical Swine Fever Virus: A Retrospective Review Spanning Half A Century

    Institute of Scientific and Technical Information of China (English)

    QIU Hua-ji; SHEN Rong-xian; TONG Guang-zhi

    2006-01-01

    Classical swine fever (CSF), a list A disease of Office International des Epizooties, is caused by classical swine fever virus (CSFV) belonging to the Flaviviridae family. The well-known lapinized Chinese strain of CSFV, also known as C-strain,was developed in China in the mid-1950s. In the past half a century, the vaccine has been proved to be safe and immunogenic in pigs of essentially any age. It is ofhigh efficacy, providing immunized animals with broad-spectrum,sometimes lifelong, protection, which is contributed by both cell-mediated immunity and humoral immunity, against essentially all genotypes or subgenotypes of the virus. The maternal antibodies derived from immunized sows can confer solid protection of their offspring from disease; however, they have been proved to inhibit the successful active immunization of C-strain vaccine. The complete genomes of C-strain and dozens of established or field strains have been sequenced and annotated. Recently, the reverse genetics system of C-strain has been developed, resulting in several Cstrain-derived candidate marker vaccines. Many countries manage to control or even eradicate CSF with the aid of mass vaccination with C-strain. In spite of these efforts, the eradication of the disease worldwide remains a big challenge and needs to go a long way, and provably still resorts to genetically modified C-strain vaccine. The authors present an overview of the characteristics of the vaccine, which has stood the test of half a century.

  12. Development of Multiple ELISAs for the Detection of Antibodies against Classical Swine Fever Virus in Pig Sera

    Institute of Scientific and Technical Information of China (English)

    Zhen-hua Yang; Ling Li; Zi-shu Pan

    2012-01-01

    The major immunogenic proteins (Ems,E2 and NS3) of classical swine fever virus (CSFV) (Shimen strain) were expressed in E.coli and purified by affinity chromatography.The recombinant antigens were applied to develop multiple enzyme-linked immunosorbent assays (ELISAs) for the detection of specific antibodies in pig sera.Optimum cut-off values were determined by receiver operating characteristic (ROC) analysis after testing 201 sera of vaccinated pigs and 64 negative sera of unvaccinated piglets.The multiple ELISAs were validated with 265 pig sera yielding high sensitivity and specificity in comparison with the virus neutralization results.The results demonstrated that multiple ELISAs can be a valuable tool for the detection of CSFV infection and serological surveys in CSFV-free countries or for the evaluation of the antibody responses in pigs induced by a live attenuated C-strain vaccination.

  13. Classical swine fever virus marker vaccine strain CP7_E2alf: genetic stability in vitro and in vivo.

    Science.gov (United States)

    Goller, Katja V; Dräger, Carolin; Höper, Dirk; Beer, Martin; Blome, Sandra

    2015-12-01

    Recently, CP7_E2alf (SuvaxynCSF Marker), a live marker vaccine against classical swine fever virus, was licensed through the European Medicines Agency. For application of such a genetically engineered virus under field conditions, knowledge about its genetic stability is essential. Here, we report on stability studies that were conducted to assess and compare the mutation rate of CP7_E2alf in vitro and in vivo. Sequence analyses upon passaging confirmed the high stability of CP7_E2alf, and no recombination events were observed in the experimental setup. The data obtained in this study confirm the genetic stability of CP7_E2alf as an important safety component. PMID:26392285

  14. Retrospective Analysis of the Oral Immunisation of Wild Boar Populations against Classical Swine Fever Virus (CSFV) in region Eifel of Rhineland-Palatinate

    OpenAIRE

    Von Rüden, Stefan; Staubach, Christoph; Kaden, Volker; Hess, R.G.; Blicke, Julia; Kühne, Sabine; Sonnenburg, Jana; Fröhlich, Andreas; Teuffert, Jürgen; Moennig, Volker

    2008-01-01

    Retrospective Analysis of the Oral Immunisation of Wild Boar Populations against Classical Swine Fever Virus (CSFV) in region Eifel of Rhineland-Palatinate GERMANY (von Ruden, Stefan) GERMANY Received: 2007-12-25 Revised: 2008-04-07 Accepted: 2008-04-18

  15. Comparison of viraemia-, clinical-based estimates of within- and between pen transmission of Classical Swine Fever Virus from three transmission experiments

    OpenAIRE

    Durand, Benoit; Davila, Sylvie; Cariolet, Roland; Mesplede, Alain; Le Potier, Marie-Frédérique

    2009-01-01

    Comparison of viraemia-, clinical-based estimates of within- and between pen transmission of Classical Swine Fever Virus from three transmission experiments FRANCE (Durand, Benoit) FRANCE Received: 2007-11-26 Revised: 2008-08-20 Accepted: 2008-09-15

  16. 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 in...

  17. Research progress on classical swine fever virus peplos glycoprotein E2%猪瘟病毒囊膜糖蛋白E2研究进展

    Institute of Scientific and Technical Information of China (English)

    宁红梅; 葛亚明; 岳锋; 王选年; 银梅

    2010-01-01

    猪瘟(classical swine fever,CSF)是危害养猪业的主要传染病之一,致病原是猪瘟病毒(classical swine fever virus,CSFV),E2囊膜糖蛋白是CSFV的主要抗原蛋白.本文对E2蛋白的分子结构、抗原特性、对病毒毒力的影响和在进入靶细胞过程中的作用等4个方面的研究现状进行了阐述.

  18. 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

    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...... 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...

  19. Identification of two amino acids within E2 important for the pathogenicity of chimeric classical swine fever virus.

    Science.gov (United States)

    Wu, Rui; Li, Ling; Zhao, Yu; Tu, Jun; Pan, Zishu

    2016-01-01

    Our previous study demonstrated that a chimeric classical swine fever virus (CSFV) vSM/CE2 containing the E2 gene of the vaccine C-strain on the genetic background of the virulent CSFV strain Shimen (vSM) was attenuated in swine but reversed to virulence after serial passages in PK15 cells. To investigate the molecular basis of the pathogenicity, the genome of the 11th passage vSM/CE2 variant (vSM/CE2-p11) was sequenced, and two amino acid mutations, T745I and M979K, within E2 of vSM/CE2-p11 were observed. Based on reverse genetic manipulation of the chimeric cDNA clone pSM/CE2, the mutated viruses vSM/CE2/T745I, vSMCE2/M979K and vSM/CE2/T745I;M979K were rescued. The data from infection of pigs demonstrated that the M979K amino acid substitution was responsible for pathogenicity. Studies in vitro indicated that T745I and M979K increased infectious virus production and replication. Our results indicated that two residues located at sites 745 and 979 within E2 play a key role in determining the replication in vitro and pathogenicity in vivo of chimeric CSFV vSM/CE2. PMID:26454191

  20. Transfection of RNA from organ samples of infected animals represents a highly sensitive method for virus detection and recovery of classical swine fever virus.

    Directory of Open Access Journals (Sweden)

    Denise Meyer

    Full Text Available Translation and replication of positive stranded RNA viruses are directly initiated in the cellular cytoplasm after uncoating of the viral genome. Accordingly, infectious virus can be generated by transfection of RNA genomes into susceptible cells. In the present study, efficiency of conventional virus isolation after inoculation of cells with infectious sample material was compared to virus recovery after transfection of total RNA derived from organ samples of pigs infected with Classical swine fever virus (CSFV. Compared to the conventional method of virus isolation applied in three different porcine cell lines used in routine diagnosis of CSF, RNA transfection showed a similar efficiency for virus rescue. For two samples, recovery of infectious virus was only possible by RNA transfection, but not by the classical approach of virus isolation. Therefore, RNA transfection represents a valuable alternative to conventional virus isolation in particular when virus isolation is not possible, sample material is not suitable for virus isolation or when infectious material is not available. To estimate the potential risk of RNA prepared from sample material for infection of pigs, five domestic pigs were oronasally inoculated with RNA that was tested positive for virus rescue after RNA transfection. This exposure did not result in viral infection or clinical disease of the animals. In consequence, shipment of CSFV RNA can be regarded as a safe alternative to transportation of infectious virus and thereby facilitates the exchange of virus isolates among authorized laboratories with appropriate containment facilities.

  1. The N-terminus of classical swine fever virus (CSFV) nonstructural protein 2 modulates viral genome RNA replication.

    Science.gov (United States)

    Li, Ling; Wu, Rui; Zheng, Fengwei; Zhao, Cheng; Pan, Zishu

    2015-12-01

    Pestivirus nonstructural protein 2 (NS2) is a multifunctional, hydrophobic protein with an important but poorly understood role in viral RNA replication and infectious virus production. In the present study, based on sequence analysis, we mutated several representative conserved residues within the N-terminus of NS2 of classical swine fever virus (CSFV) and investigated how these mutations affected viral RNA replication and infectious virus production. Our results demonstrated that the mutation of two aspartic acids, NS2/D60A or NS2/D60K and NS2/D78K, in the N-terminus of NS2 abolished infectious virus production and that the substitution of arginine for alanine at position 100 (NS2/R100A) resulted in significantly decreased viral titer. The serial passage of cells containing viral genomic RNA molecules generated the revertants NS2/A60D, NS2/K60D and NS2/K78D, leading to the recovery of infectious virus. In the context of the NS2/R100A mutant, the NS2/I90L mutation compensated for infectious virus production. The regulatory roles of the indicated amino acid residues were identified to occur at the viral RNA replication level. These results revealed a novel function for the NS2 N-terminus of CSFV in modulating viral RNA replication. PMID:26232654

  2. Generation and Efficacy Evaluation of a Recombinant Pseudorabies Virus Variant Expressing the E2 Protein of Classical Swine Fever Virus in Pigs.

    Science.gov (United States)

    Wang, Yimin; Yuan, Jin; Cong, Xin; Qin, Hua-Yang; Wang, Chun-Hua; Li, Yongfeng; Li, Su; Luo, Yuzi; Sun, Yuan; Qiu, Hua-Ji

    2015-10-01

    Classical swine fever (CSF) is an economically important infectious disease of pigs caused by classical swine fever virus (CSFV). Pseudorabies (PR), which is caused by pseudorabies virus (PRV), is another important infectious disease of pigs and other animals. Coinfections of pigs with PRV and CSFV occur occasionally in the field. The modified live vaccine Bartha-K61 strain has played an important role in the control of PR in many countries, including China. Since late 2011, however, increasing PR outbreaks caused by an emerging PRV variant have been reported in Bartha-K61-vaccinated swine populations on many farms in China. Previously, we generated a gE/gI-deleted PRV (rPRVTJ-delgE) based on this PRV variant, which was shown to be safe and can provide rapid and complete protection against lethal challenge with the PRV variant in pigs. Here, we generated a new recombinant PRV variant expressing the E2 gene of CSFV (rPRVTJ-delgE/gI-E2) and evaluated its immunogenicity and efficacy in pigs. The results showed that rPRVTJ-delgE/gI-E2 was safe for pigs, induced detectable anti-PRV and anti-CSFV neutralizing antibodies, and provided complete protection against the lethal challenge with either the PRV TJ strain or the CSFV Shimen strain. The data indicate that rPRVTJ-delgE/gI-E2 is a promising candidate bivalent vaccine against PRV and CSFV coinfections. PMID:26311244

  3. Applying participatory approaches in the evaluation of surveillance systems: A pilot study on African swine fever surveillance in Corsica.

    Science.gov (United States)

    Calba, Clémentine; Antoine-Moussiaux, Nicolas; Charrier, François; Hendrikx, Pascal; Saegerman, Claude; Peyre, Marisa; Goutard, Flavie L

    2015-12-01

    The implementation of regular and relevant evaluations of surveillance systems is critical in improving their effectiveness and their relevance whilst limiting their cost. The complex nature of these systems and the variable contexts in which they are implemented call for the development of flexible evaluation tools. Within this scope, participatory tools have been developed and implemented for the African swine fever (ASF) surveillance system in Corsica (France). The objectives of this pilot study were, firstly, to assess the applicability of participatory approaches within a developed environment involving various stakeholders and, secondly, to define and test methods developed to assess evaluation attributes. Two evaluation attributes were targeted: the acceptability of the surveillance system and its the non-monetary benefits. Individual semi-structured interviews and focus groups were implemented with representatives from every level of the system. Diagramming and scoring tools were used to assess the different elements that compose the definition of acceptability. A contingent valuation method, associated with proportional piling, was used to assess the non-monetary benefits, i.e., the value of sanitary information. Sixteen stakeholders were involved in the process, through 3 focus groups and 8 individual semi-structured interviews. Stakeholders were selected according to their role in the system and to their availability. Results highlighted a moderate acceptability of the system for farmers and hunters and a high acceptability for other representatives (e.g., private veterinarians, local laboratories). Out of the 5 farmers involved in assessing the non-monetary benefits, 3 were interested in sanitary information on ASF. The data collected via participatory approaches enable relevant recommendations to be made, based on the Corsican context, to improve the current surveillance system. PMID:26489602

  4. Intra-host variation structure of classical swine fever virus NS5B in relation to antiviral therapy.

    Science.gov (United States)

    Haegeman, Andy; Vrancken, Robert; Neyts, Johan; Koenen, Frank

    2013-05-01

    Classical swine fever (CSF) is one of most important diseases of the Suidea with severe social economic consequences in case of outbreaks. Antivirals have been demonstrated, in recent publications, to be an interesting alternative method of fighting the disease. However, classical swine fever virus is an RNA virus which presents a challenge as intra-host variation and the error prone RNA dependent RNA polymerase (RdRp) could lead to the emergence/selection of resistant variants hampering further treatment. Therefore, it was the purpose of this study to investigate the intra-host variation of the RdRp gene, targeted by antivirals, in respect to antiviral treatment. Using the non-unique nucleotide changes, a limited intra-host variation was found in the wild type virus with 2 silent and 2 non-synonymous sites. This number shifted significantly when an antiviral resistant variant was analyzed. In total 22nt changes were found resulting in 14 amino acid changes whereby each genome copy contained at least 2 amino-acid changes in the RdRp. Interestingly, the frequency of the mutations situated in close proximity to a region involved in antiviral resistance in CSFV and bovine viral diarrhea virus (BVDV) was elevated compared to the other mutations. None of the identified mutations in the resistant variant and which could potentially result in antiviral resistance was present in the wild type virus as a non-unique mutation. In view of the spectrum of mutations identified in the resistance associated region and that none of the resistance associated mutations reported for another strain of classical swine fever for the same antiviral were observed in the study, it can be suggested that multiple mutations confer resistance to some degree. Although the followed classical approach allowed the analysis the RdRp as a whole, the contribution of unique mutations to the intra-host variation could not be completely resolved. There was a significant difference in de number of unique

  5. 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; Cui, Li-Chun

    2015-06-01

    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 < 0.05) in the levels of immune responses were observed between L. 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

  6. Passive immunity evaluation in piglets originating from sows vaccinated with China strain of classical swine fever virus

    Directory of Open Access Journals (Sweden)

    Prodanov Jasna

    2007-01-01

    Full Text Available An experimental study was conducted to investigate the course of classical swine fever (CSF infection in piglets originating from sows vaccinated with China strain vaccine. The experiment was carried out on 24 piglets (age 28, 35, 44 and 54 days from vaccinated sows and on 11 non vaccinated piglets, originated from non CSF vaccinated sows. Two piglets from the each age group originating from vaccinated sows were challenged by intramuscular injection with CSF virus. Four piglets of the same age from vaccinated sows, and two piglets derived from unvaccinated sows were added to the challenged group to determine contact (horizontal infection. After challenge, clinical examination and blood sampling from every animal was carried out on day 0, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27 and 29. Blood samples were examined for CSF virus specific antibodies by ELISA test, and for viral antigen i. e. viral RNA by RT-PCR technique. After death or sacrifice pathomorphological changes, presence and distribution of CSF virus antigen were detected in piglet tissue samples by ELISA test. On the basis of the obtained results it can be concluded that not all piglets born to vaccinated sows have maternal antibodies at a detectable level, and the issue of the efficiency of passive immunization needs to be evaluated in the future.

  7. 猪瘟病毒对IFN-β启动子活化%The activation of IFN-β promoter mediated by classical swine fever virus

    Institute of Scientific and Technical Information of China (English)

    夏燕华; 赵天生

    2012-01-01

    Classical swine fever virus can persistently infect swine for its ability to escape the killing of immune system. In order to prove it,Newcastle disease virus as IFN inducer,firefly luciferase reporter system was used to test the effect on interferon-beta promoter induced by CSFV Shimen strain. Results demonstrate that CSFV can't induce IFN-βpromoter but can obviously inhibit the NDV-mediated-activation, which prove that CSFV escape from the killing of immune system by inhibiting IFN production. The research partly explains why CSFV can establish persistent infection in swine.%猪瘟病毒(Classical swine fever virus,CSFV)之所以能在猪体中建立持续感染,与其逃避宿主的免疫清除有关,据此,本课题以新城疫病毒(Newcastle disease virus,NDV)作为诱导剂,利用荧光素酶报告基因系统测定了CSFV Shimen株对IFN-β启动子活化的影响.结果表明CSFV不仅不能活化IFN-β启动子,而且能明显抑制NDV对IFN-β启动子的活化作用,说明CSFV可通过抑制IFN产生来逃避机体的免疫清除,为病毒建立持续性感染创造条件.

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

    International Nuclear Information System (INIS)

    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/CP7E2alf. After transfection of in vitro-transcribed CP7E2alf RNA, autonomous replication of chimeric RNA in bovine and porcine cell cultures was observed. Efficient growth of chimeric CP7E2alf virus, however, could only be demonstrated on porcine cells, and in contrast to the parental BVDV strain CP7, CP7E2alf only inefficiently infected and propagated in bovine cells. The virulence, immunogenicity, and 'marker vaccine' properties of the generated chimeric CP7E2alf virus were determined in an animal experiment using 27 pigs. After intramuscular inoculation of 1 x 107 TCID50, CP7E2alf 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-ERNS-specific antibodies as determined with a CSFV marker ELISA. After challenge infection with highly virulent CSFV strain Eystrup, pigs immunized with CP7E2alf 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 CP7E2alf 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'

  9. Evidence for widespread infection of African bats with Crimean-Congo hemorrhagic fever-like viruses.

    Science.gov (United States)

    Müller, Marcel A; Devignot, Stéphanie; Lattwein, Erik; Corman, Victor Max; Maganga, Gaël D; Gloza-Rausch, Florian; Binger, Tabea; Vallo, Peter; Emmerich, Petra; Cottontail, Veronika M; Tschapka, Marco; Oppong, Samuel; Drexler, Jan Felix; Weber, Friedemann; Leroy, Eric M; Drosten, Christian

    2016-01-01

    Crimean Congo hemorrhagic fever virus (CCHFV) is a highly virulent tick-borne pathogen that causes hemorrhagic fever in humans. The geographic range of human CCHF cases largely reflects the presence of ticks. However, highly similar CCHFV lineages occur in geographically distant regions. Tick-infested migratory birds have been suggested, but not confirmed, to contribute to the dispersal. Bats have recently been shown to carry nairoviruses distinct from CCHFV. In order to assess the presence of CCHFV in a wide range of bat species over a wide geographic range, we analyzed 1,135 sera from 16 different bat species collected in Congo, Gabon, Ghana, Germany, and Panama. Using a CCHFV glycoprotein-based indirect immunofluorescence test (IIFT), we identified reactive antibodies in 10.0% (114/1,135) of tested bats, pertaining to 12/16 tested species. Depending on the species, 3.6%-42.9% of cave-dwelling bats and 0.6%-7.1% of foliage-living bats were seropositive (two-tailed t-test, p = 0.0447 cave versus foliage). 11/30 IIFT-reactive sera from 10 different African bat species had neutralizing activity in a virus-like particle assay. Neutralization of full CCHFV was confirmed in 5 of 7 sera. Widespread infection of cave-dwelling bats may indicate a role for bats in the life cycle and geographic dispersal of CCHFV. PMID:27217069

  10. Evidence for widespread infection of African bats with Crimean-Congo hemorrhagic fever-like viruses

    Science.gov (United States)

    Müller, Marcel A.; Devignot, Stéphanie; Lattwein, Erik; Corman, Victor Max; Maganga, Gaël D.; Gloza-Rausch, Florian; Binger, Tabea; Vallo, Peter; Emmerich, Petra; Cottontail, Veronika M.; Tschapka, Marco; Oppong, Samuel; Drexler, Jan Felix; Weber, Friedemann; Leroy, Eric M.; Drosten, Christian

    2016-01-01

    Crimean Congo hemorrhagic fever virus (CCHFV) is a highly virulent tick-borne pathogen that causes hemorrhagic fever in humans. The geographic range of human CCHF cases largely reflects the presence of ticks. However, highly similar CCHFV lineages occur in geographically distant regions. Tick-infested migratory birds have been suggested, but not confirmed, to contribute to the dispersal. Bats have recently been shown to carry nairoviruses distinct from CCHFV. In order to assess the presence of CCHFV in a wide range of bat species over a wide geographic range, we analyzed 1,135 sera from 16 different bat species collected in Congo, Gabon, Ghana, Germany, and Panama. Using a CCHFV glycoprotein-based indirect immunofluorescence test (IIFT), we identified reactive antibodies in 10.0% (114/1,135) of tested bats, pertaining to 12/16 tested species. Depending on the species, 3.6%–42.9% of cave-dwelling bats and 0.6%–7.1% of foliage-living bats were seropositive (two-tailed t-test, p = 0.0447 cave versus foliage). 11/30 IIFT-reactive sera from 10 different African bat species had neutralizing activity in a virus-like particle assay. Neutralization of full CCHFV was confirmed in 5 of 7 sera. Widespread infection of cave-dwelling bats may indicate a role for bats in the life cycle and geographic dispersal of CCHFV. PMID:27217069

  11. African tick bite fever

    DEFF Research Database (Denmark)

    Johansen, Jakob Aaquist; Thybo, Søren

    2011-01-01

    The incident of spotted fever imported to Denmark is unknown. We present a classic case of African Tick Bite Fever (ATBF) to highlight a disease, which frequently infects wildlife enthusiasts and hunters on vacation in South Africa. ATBF has a good prognosis and is easily treated with doxycyclin...

  12. Development of a live attenuated antigenic marker classical swine fever vaccine

    Science.gov (United States)

    Classical Swine Fever, caused by Classical Swine Fever Virus (CSFV), is a highly contagious disease affecting swine worldwide. The two main strategies for disease control are prophylactic vaccination and non-vaccination “stamping out” policies. In a vaccination-to-live strategy, marker vaccines coul...

  13. Complete Genome Sequence of a Field Isolate of Classical Swine Fever Virus Belonging to Subgenotype 2.1b from Hunan Province, China

    OpenAIRE

    Shao, Weixing; Liu, Shuang; Wu, Faxing; Zhang, Zhi; Dong, Yaqin; Li, Xiaocheng

    2015-01-01

    We report the complete genome sequence of a field isolate of classical swine fever virus (CSFV), Hunan 23/2013, belonging to the predominant subgenotype 2.1b. This strain was originally isolated from diseased pigs in Hunan Province, China. This report will help in understanding the molecular diversity of CSFV stains circulating in China and in selecting and developing a suitable vaccine candidate for CSF control.

  14. Complete Genome Sequence of a Field Isolate of Classical Swine Fever Virus Belonging to Subgenotype 2.1b from Hunan Province, China.

    Science.gov (United States)

    Shao, Weixing; Liu, Shuang; Wu, Faxing; Zhang, Zhi; Dong, Yaqin; Li, Xiaocheng

    2015-01-01

    We report the complete genome sequence of a field isolate of classical swine fever virus (CSFV), Hunan 23/2013, belonging to the predominant subgenotype 2.1b. This strain was originally isolated from diseased pigs in Hunan Province, China. This report will help in understanding the molecular diversity of CSFV stains circulating in China and in selecting and developing a suitable vaccine candidate for CSF control. PMID:26205876

  15. Complete Genome Sequence of Classical Swine Fever Virus Strain JSZL, Belonging to a New Subgenotype, 2.1d, Isolated in China in 2014.

    Science.gov (United States)

    Zhang, Hongliang; Feng, Liping; Liu, Chunxiao; Chen, Jiazeng; Leng, Chaoliang; Bai, Yun; Peng, Jinmei; An, Tongqing; Cai, Xuehui; Yang, Xufu; Tian, Zhijun; Tong, Guangzhi

    2015-01-01

    The complete genome sequence of classic swine fever virus (CSFV) strain JSZL was determined in this study. JSZL was originally isolated from an immune pig farm in Jiangsu Province, China. JSZL is more closely related to subgenotype 2.1b than to 2.1a and 2.1c. Importantly, JSZL was classified into a new subgenotype, 2.1d. PMID:26294620

  16. Generation and efficacy evaluation of recombinant classical swine fever virus E2 glycoprotein expressed in stable transgenic mammalian cell line.

    Directory of Open Access Journals (Sweden)

    Rong-Hong Hua

    Full Text Available Classical swine fever virus (CSFV is the causative agent of classical swine fever (CSF, which is a highly contagious swine disease that causes significant economic loses to the pig industry worldwide. The envelope E2 glycoprotein of CSFV is the most important viral antigen in inducing protective immune response against CSF. In this study, we generated a mammalian cell clone (BCSFV-E2 that could stably produce a secreted form of CSFV E2 protein (mE2. The mE2 protein was shown to be N-linked glycosylated and formed a homodimer. The vaccine efficacy of mE2 was evaluated by immunizing pigs. Twenty-five 6-week-old Landrace piglets were randomly divided into five groups. Four groups were intramuscularly immunized with mE2 emulsified in different adjuvants twice at four-week intervals. One group was used as the control group. All mE2-vaccinated pigs developed CSFV-neutralizing antibodies two weeks after the first vaccination with neutralizing antibody titers ranging from 1:40 to 1:320. Two weeks after the booster vaccination, the neutralizing antibody titers increased greatly and ranged from 1:10,240 to 1:81,920. At 28 weeks after the booster vaccine was administered, the neutralizing antibody titers ranged from 1:80 to 1:10240. At 32 weeks after the first vaccination, pigs in all the groups were challenged with a virulent CSFV strain at a dose of 1 × 10(5 TCID50. At two weeks after the challenge, all the mE2-immunized pigs survived and exhibited no obvious symptoms of CSF. The neutralizing antibody titer at this time was 20,480. Unvaccinated pigs in the control group exhibited symptoms of CSF 3-4 days after challenge and were euthanized from 7-9 days after challenge when the pigs became moribund. These results indicate that the mE2 is a good candidate for the development of a safe and effective CSFV subunit vaccine.

  17. Persistent Classical Swine Fever infection in newborn piglets

    DEFF Research Database (Denmark)

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

    Pestiviruses are unique in their ability to cause persistent infection (PI) in pigs infected in utero. In cattle, PI calves play an important role in maintenance of bovine viral diarrhoea virus infection in the herd. In pigs, the occurence of classical swine fever virus (CSFV) PI piglets is...

  18. Classical swine fever virus marker vaccine strain CP7_E2alf: Shedding and dissemination studies in boars.

    Science.gov (United States)

    Dräger, Carolin; Petrov, Anja; Beer, Martin; Teifke, Jens P; Blome, Sandra

    2015-06-17

    Over the last decade, pestivirus chimaera CP7_E2alf has proven to be a most promising marker vaccine candidate against classical swine fever (CSF). To provide further background data for the risk assessment towards licensing and release, especially on presence of the vaccine chimaera in faeces, urine, and organs of the male reproductive tract, supplementary studies were carried out under controlled laboratory conditions. In detail, the shedding and dissemination pattern of Suvaxyn(®) CSF Marker ("CP7_E2alf") was assessed in 12 adult boars after single intramuscular vaccination with a tenfold vaccine dose. Four and seven days post vaccination, six animals were subjected to necropsy and triplicate samples were obtained from reproductive and lymphatic organs as well as urine, faeces, blood, and several additional organs and matrices. The sampling days were chosen based on pre-existing data that indicated the highest probability of virus detection. Upon vaccination, neither local nor systemic adverse effects were observed in the experimental animals. It was confirmed that primary replication is restricted to the lymphatic tissues and especially the tonsil. While viral genome was detectable in several samples from lymphatic tissues at four and seven days post vaccination, infectious virus was only demonstrated at four days post vaccination in one tonsil sample and one parotid lymphnode. Sporadic detection at a very low level occurred in some replicates of liver, lung, bone marrow, and salivary gland samples. In contrast, viral genome was not detected in any sample from reproductive organs and accessory sex glands, in faeces, urine, or bile. The presented data on the dissemination of the vaccine virus CP7_E2alf in adult boars are supplementing existing safety and efficacy studies and indicate that the use of the vaccine is also safe in reproductive boars. PMID:25980427

  19. Porcine circovirus type 2 (PCV2 infection decreases the efficacy of an attenuated classical swine fever virus (CSFV vaccine

    Directory of Open Access Journals (Sweden)

    Huang Yu-Liang

    2011-12-01

    Full Text Available Abstract The Lapinized Philippines Coronel (LPC vaccine, an attenuated strain of classical swine fever virus (CSFV, is an important tool for the prevention and control of CSFV infection and is widely and routinely used in most CSF endemic areas, including Taiwan. The aim of this study was to investigate whether PCV2 infection affects the efficacy of the LPC vaccine. Eighteen 6-week-old, cesarean-derived and colostrum-deprived (CDCD, crossbred pigs were randomly assigned to four groups. A total of 105.3 TCID50 of PCV2 was experimentally inoculated into pigs through both intranasal and intramuscular routes at 0 days post-inoculation (dpi followed by LPC vaccination 12 days later. All the animals were challenged with wild-type CSFV (ALD stain at 27 dpi and euthanized at 45 dpi. Following CSFV challenge, the LPC-vaccinated pigs pre-inoculated with PCV2 showed transient fever, viremia, and viral shedding in the saliva and feces. The number of IgM+, CD4+CD8-CD25+, CD4+CD8+CD25+, and CD4-CD8+CD25+ lymphocyte subsets and the level of neutralizing antibodies against CSFV were significantly higher in the animals with LPC vaccination alone than in the pigs with PCV2 inoculation/LPC vaccination. In addition, PCV2-derived inhibition of the CSFV-specific cell proliferative response of peripheral blood mononuclear cells (PBMCs was demonstrated in an ex vivo experiment. These findings indicate that PCV2 infection decreases the efficacy of the LPC vaccine. This PCV2-derived interference may not only allow the invasion of wild-type CSFV in pig farms but also increases the difficulty of CSF prevention and control in CSF endemic areas.

  20. 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.

  1. Candidate Multi-Peptide-Vaccine Against Classical Swine Fever Virus Induces Strong Antibody Response with Predefined Specificity

    Institute of Scientific and Technical Information of China (English)

    张耿; 董晓楠; 陈应华

    2002-01-01

    Previous investigations demonstrated that the envelope glycoprotein E2 (gp55) of classical swine fever virus (CSFV) is the most immunogenic protein. Interestingly, recombinant protein E2 that contains only one structural antigenic unit (unit B/C or A) could protect pigs from a lethal challenge of CSFV. Based on these findings, we designed and prepared five overlapping synthetic peptides that covered the sequence unit B/C (aa 693-777) of Shimen E2 and conjugated individual peptides with bovine serum albumin (BSA). After the vaccination, the specificity of the rabbit sera was analyzed in the enzyme-linked immunosorbent assay (ELISA) and the fast protein liquid chromatography (FPLC). The results show that each of the five candidate peptide-vaccines can successfully induce a high titer of specific antibodies in New Zealand White Rabbits (n=3). Subsequently, the five candidate peptide-vaccines were applied in combination for immunization of pigs (n=10) and induced specific and strong humoral responses against all of the five designed peptides in pigs. Our studies indicate that the candidate multi-peptide-vaccine would prove an excellent marker vaccine against CSFV and provide a model for developing effective synthetic peptide vaccines to stop viral epidemics in humans and animals.

  2. In planta production of two peptides of the Classical Swine Fever Virus (CSFV E2 glycoprotein fused to the coat protein of potato virus X

    Directory of Open Access Journals (Sweden)

    Lico Chiara

    2006-06-01

    Full Text Available Abstract Background Classical Swine Fever (CSFV is one of the most important viral infectious diseases affecting wild boars and domestic pigs. The etiological agent of the disease is the CSF virus, a single stranded RNA virus belonging to the family Flaviviridae. All preventive measures in domestic pigs have been focused in interrupting the chain of infection and in avoiding the spread of CSFV within wild boars as well as interrupting transmission from wild boars to domestic pigs. The use of plant based vaccine against CSFV would be advantageous as plant organs can be distributed without the need of particular treatments such as refrigeration and therefore large areas, populated by wild animals, could be easily covered. Results We report the in planta production of peptides of the classical swine fever (CSF E2 glycoprotein fused to the coat protein of potato virus X. RT-PCR studies demonstrated that the peptide encoding sequences are correctly retained in the PVX construct after three sequential passage in Nicotiana benthamiana plants. Sequence analysis of RT-PCR products confirmed that the epitope coding sequences are replicated with high fidelity during PVX infection. Partially purified virions were able to induce an immune response in rabbits. Conclusion Previous reports have demonstrated that E2 synthetic peptides can efficiently induce an immunoprotective response in immunogenized animals. In this work we have showed that E2 peptides can be expressed in planta by using a modified PVX vector. These results are particularly promising for designing strategies for disease containment in areas inhabited by wild boars.

  3. Experimental infection with the Paderborn isolate of classical swine fever virus in 10-week-old pigs: determination of viral replication kinetics by quantitative RT-PCR, virus isolation and antigen ELISA

    DEFF Research Database (Denmark)

    Uttenthal, Åse; Storgaard, Torben; Oleksiewicz, M.B.;

    2003-01-01

    We performed experimental infection in 10-week-old pigs with the Paderborn isolate of classical swine fever virus (CSFV). Despite being epidemiologically linked to the major CSFV outbreak in The Netherlands in 1997, the in vivo replication kinetics of this isolate have to our knowledge not been...

  4. Classical swine fever virus failed to activate nuclear factor-kappa b signaling pathway both in vitro and in vivo

    Directory of Open Access Journals (Sweden)

    Chen Li-Jun

    2012-11-01

    Full Text Available Abstract Background Classical swine fever virus (CSFV is the cause of CSF which is a severe disease of pigs, leading to heavy economic losses in many regions of the world. Nuclear factor-kappa B (NF-κB is a critical regulator of innate and adaptive immunity, and commonly activated upon viral infection. In our previous study, we found that CSFV could suppress the maturation and modulate the functions of monocyte-derived dendritic cells (Mo-DCs without activating NF-κB pathway. To further prove the effects of CSFV on the NF-κB signaling pathway, we investigated the activity of NF-κB after CSFV infection in vivo and in vitro. Methods Attenuated Thiverval strain and virulent wild-type GXW-07 strain were used as challenge viruses in this study. Porcine kidney 15 (PK-15 cells were cultured in vitro and peripheral blood mononuclear cells (PBMCs were isolated from the blood of CSFV-infected pigs. DNA binding of NF-κB was measured by electrophoretic mobility shift assays (EMSA, NF-κB p65 translocation was detected using immunofluorescent staining, and p65/RelA and IκBα expression was measured by Western Blotting. Results Infection of cells with CSFV in vitro and in vivo showed that compared with tumor necrosis factor alpha (TNF-α stimulated cells, there was no distinct DNA binding band of NF-κB, and no significant translocation of p65/RelA from the cytoplasm to the nucleus was observed, which might have been due to the apparent lack of IkBa degradation. Conclusions CSFV infection had no effect on the NF-κB signaling pathway, indicating that CSFV could evade host activation of NF-κB during infection.

  5. Molecular modeling and pharmacophore elucidation study of the Classical Swine Fever virus helicase as a promising pharmacological target

    Directory of Open Access Journals (Sweden)

    Dimitrios Vlachakis

    2013-06-01

    Full Text Available The Classical Swine Fever virus (CSFV is a major pathogen of livestock and belongs to the flaviviridae viral family. Even though there aren’t any verified zoonosis cases yet, the outcomes of CSFV epidemics have been devastating to local communities. In an effort to shed light to the molecular mechanisms underlying the structural and drug design potential of the viral helicase, the three dimensional structure of CSFV helicase has been modeled using conventional homology modeling techniques and the crystal structure of the Hepatitis C virus (HCV as a template. The established structure of the CSFV helicase has been in silico evaluated for its viability using a repertoire of in silico tools. The ultimate goal of this study is to introduce the 3D conformation of the CSFV helicase as a reliable structure that may be used as the designing platform for de novo, structure-based drug design experiments. In this direction using the modeled structure of CSVF helicase, a 3D pharmacophore was designed. The pharmacophore comprises of a series of key characteristics that molecular inhibitors must satisfy in order to achieve maximum predicted affinity for the given enzyme. Overall, invaluable insights and conclusions are drawn from this structural study of the CSFV helicase, which may provide the scientific community with the founding plinth in the fight against CSFV infections through the perspective of the CSFV helicase as a potential pharmacological target. Notably, to date no antiviral agent is available against the CSFV nor is expected soon. Subsequently, there is urgent need for new modern and state-of-the-art antiviral strategies to be developed.

  6. Spatio-temporal patterns and movement analysis of pigs from smallholder farms and implications for African swine fever spread, Limpopo province, South Africa.

    Science.gov (United States)

    Fasina, Folorunso O; Mokoele, Japhta M; Spencer, B Tom; Van Leengoed, Leo A M L; Bevis, Yvette; Booysen, Ingrid

    2015-01-01

    Infectious and zoonotic disease outbreaks have been linked to increasing volumes of legal and illegal trade. Spatio-temporal and trade network analyses have been used to evaluate the risks associated with these challenges elsewhere, but few details are available for the pig sector in South Africa. Regarding pig diseases, Limpopo province is important as the greater part of the province falls within the African swine fever control area. Emerging small-scale pig farmers in Limpopo perceived pig production as an important means of improving their livelihood and an alternative investment. They engage in trading and marketing their products with a potential risk to animal health, because the preferred markets often facilitate potential longdistance spread and disease dispersal over broad geographic areas. In this study, we explored the interconnectedness of smallholder pig farmers in Limpopo, determined the weaknesses and critical control points, and projected interventions that policy makers can implement to reduce the risks to pig health. The geo-coordinates of surveyed farms were used to draw maps, links and networks. Predictive risks to pigs were determined through the analyses of trade networks, and the relationship to previous outbreaks of African swine fever was postulated. Auction points were identified as high-risk areas for the spread of animal diseases. Veterinary authorities should prioritise focused surveillance and diagnostic efforts in Limpopo. Early disease detection and prompt eradication should be targeted and messages promoting enhanced biosecurity to smallholder farmers are advocated. The system may also benefit from the restructuring of marketing and auction networks. Since geographic factors and networks can rapidly facilitate pig disease dispersal over large areas, a multi-disciplinary approach to understanding the complexities that exist around the animal disease epidemiology becomes mandatory. PMID:26842362

  7. Spatio-temporal patterns and movement analysis of pigs from smallholder farms and implications for African swine fever spread, Limpopo province, South Africa

    Directory of Open Access Journals (Sweden)

    Folorunso O. Fasina

    2015-02-01

    Full Text Available Infectious and zoonotic disease outbreaks have been linked to increasing volumes of legal and illegal trade. Spatio-temporal and trade network analyses have been used to evaluate the risks associated with these challenges elsewhere, but few details are available for the pig sector in South Africa. Regarding pig diseases, Limpopo province is important as the greater part of the province falls within the African swine fever control area. Emerging small-scale pig farmers in Limpopo perceived pig production as an important means of improving their livelihood and an alternative investment. They engage in trading and marketing their products with a potential risk to animal health, because the preferred markets often facilitate potential longdistance spread and disease dispersal over broad geographic areas. In this study, we explored the interconnectedness of smallholder pig farmers in Limpopo, determined the weaknesses and critical control points, and projected interventions that policy makers can implement to reduce the risks to pig health. The geo-coordinates of surveyed farms were used to draw maps, links and networks. Predictive risks to pigs were determined through the analyses of trade networks, and the relationship to previous outbreaks of African swine fever was postulated. Auction points were identified as high-risk areas for the spread of animal diseases. Veterinary authorities should prioritise focused surveillance and diagnostic efforts in Limpopo. Early disease detection and prompt eradication should be targeted and messages promoting enhanced biosecurity to smallholder farmers are advocated. The system may also benefit from the restructuring of marketing and auction networks. Since geographic factors and networks can rapidly facilitate pig disease dispersal over large areas, a multi-disciplinary approach to understanding the complexities that exist around the animal disease epidemiology becomes mandatory.

  8. 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.

  9. 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

  10. In Vitro Coinfection and Replication of Classical Swine Fever Virus and Porcine Circovirus Type 2 in PK15 Cells.

    Directory of Open Access Journals (Sweden)

    Niu Zhou

    Full Text Available Increasing clinical lines of evidence have shown the coinfection/superinfection of porcine circovirus type 2 (PCV2 and classical swine fever virus (CSFV. Here, we investigated whether PCV2 and CSFV could infect the same cell productively by constructing an in vitro coinfection model. Our results indicated that PCV2-free PK15 cells but not ST cells were more sensitive to PCV2, and the PK15 cell line could stably harbor replicating CSFV (PK15-CSFV cells with a high infection rate. Confocal and super-resolution microscopic analysis showed that PCV2 and CSFV colocalized in the same PK15-CSFV cell, and the CSFV E2 protein translocated from the cytoplasm to the nucleus in PK15-CSFV cells infected with PCV2. Moreover, PCV2-CSFV dual-positive cells increased gradually in PK15-CSFV cells in a PCV2 dose-dependent manner. In PK15-CSFV cells, PCV2 replicated well, and the production of PCV2 progeny was not influenced by CSFV infection. However, CSFV reproduction decreased in a PCV2 dose-dependent manner. In addition, cellular apoptosis was not strengthened in PK15-CSFV cells infected with PCV2 in comparison with PCV2-infected PK15 cells. Moreover, using this coinfection model we further demonstrated PCV2-induced apoptosis might contribute to the impairment of CSFV HCLV strain replication in coinfected cells. Taken together, our results demonstrate for the first time the coinfection/superinfection of PCV2 and CSFV within the same cell, providing an in vitro model to facilitate further investigation of the underlying mechanism of CSFV and PCV2 coinfection.

  11. An investigation of classical swine fever virus seroprevalence and risk factors in pigs in Timor-Leste.

    Science.gov (United States)

    Sawford, Kate; do Karmo, Antonino; da Conceicao, Felisiano; Geong, Maria; Tenaya, I Wayan Masa; Hartawan, Dinar H W; Toribio, Jenny-Ann L M L

    2015-11-01

    Classical swine fever virus (CSFV) is a highly infectious pathogen of pigs and believed to be a major constraint to pig production in Timor-Leste. The Ministry of Agriculture and Fisheries conducts vaccination campaigns in an attempt to control clinical disease, however, there is no empirical data available concerning the seroprevalence and distribution of CSFV in Timor-Leste. To help address this knowledge deficit, a cross-sectional study to determine seroprevalence was conducted in the three districts that border Indonesia. Data on farmer- and pig-level factors were also collected to look at their impact on CSFV serological status. Overall, true CSFV seroprevalence was estimated at 34.4%. Seroprevalence estimates varied widely between and within districts, subdistricts, and villages. Older pigs and pigs that had been vaccinated for CSFV were more likely to test positive for CSFV antibody. Pigs owned by farmers that experienced the sudden death of pigs in the 12 months prior to the survey were more likely to test positive for CSFV antibody, while pigs that had been sick in the previous three months were less likely to test positive for CSFV antibody. The final multivariable model accounted for a large amount of variation in the data, however, much of this variation was explained by the random effects with less than one percent of the variation explained by the fixed effects. This work further supports the need for a collaborative approach to whole-island CSFV control between West Timor, Indonesia and Timor-Leste. Further work is needed to better understand the risk factors for CSFV serological status in order to allocate resources for control. As CSFV is now endemic in Timor-Leste research involving a combination of serology, antigen detection and in-depth investigation of suspect cases over a period of time may be required. PMID:26433742

  12. Improved strategy for phylogenetic analysis of classical swine fever virus based on full-length E2 encoding sequences

    Directory of Open Access Journals (Sweden)

    Postel Alexander

    2012-06-01

    Full Text Available Abstract Molecular epidemiology has proven to be an essential tool in the control of classical swine fever (CSF and its use has significantly increased during the past two decades. Phylogenetic analysis is a prerequisite for virus tracing and thus allows implementing more effective control measures. So far, fragments of the 5´NTR (150 nucleotides, nt and the E2 gene (190 nt have frequently been used for phylogenetic analyses. The short sequence lengths represent a limiting factor for differentiation of closely related isolates and also for confidence levels of proposed CSFV groups and subgroups. In this study, we used a set of 33 CSFV isolates in order to determine the nucleotide sequences of a 3508–3510 nt region within the 5´ terminal third of the viral genome. Including 22 additional sequences from GenBank database different regions of the genome, comprising the formerly used short 5´NTR and E2 fragments as well as the genomic regions encoding the individual viral proteins Npro, C, Erns, E1, and E2, were compared with respect to variability and suitability for phylogenetic analysis. Full-length E2 encoding sequences (1119 nt proved to be most suitable for reliable and statistically significant phylogeny and analyses revealed results as good as obtained with the much longer entire 5´NTR-E2 sequences. This strategy is therefore recommended by the EU and OIE Reference Laboratory for CSF as it provides a solid and improved basis for CSFV molecular epidemiology. Finally, the power of this method is illustrated by the phylogenetic analysis of closely related CSFV isolates from a recent outbreak in Lithuania.

  13. Nucleotide sequence of classical swine fever virus strain Alfort/187 and transcription of infectious RNA from stably cloned full-length cDNA.

    OpenAIRE

    Ruggli, N; Tratschin, J D; Mittelholzer, C.; Hofmann, M A

    1996-01-01

    The complete nucleotide sequence of the genome of classical swine fever virus (CSFV) strain Alfort/187 was determined from three cDNA libraries constructed by cloning of DNA fragments obtained from independent sets of reverse transcription and PCR. The cDNA fragments were then assembled and inserted downstream of a T7 promoter in a P15A-derived plasmid vector to obtain the full-length cDNA clone pA187-1. The first nucleotide of the CSFV genome was positioned at the transcription start site of...

  14. Residual viruses in pork products.

    Science.gov (United States)

    McKercher, P D; Hess, W R; Hamdy, F

    1978-01-01

    Partly cooked canned hams and dried pepperoni and salami sausages were prepared from the carcasses of pigs infected with African swine fever virus and pigs infected with hog cholera virus. Virus was not recovered from the partly cooked canned hams; however, virus was recovered in the hams before heating in both instances. Both African swine fever virus and hog cholera virus were recovered from the dried salami and pepperoni sausages, but not after the required curing period. PMID:564162

  15. Guanylate-Binding Protein 1, an Interferon-Induced GTPase, Exerts an Antiviral Activity against Classical Swine Fever Virus Depending on Its GTPase Activity

    Science.gov (United States)

    Li, Lian-Feng; Yu, Jiahui; Li, Yongfeng; Wang, Jinghan; Li, Su; Zhang, Lingkai; Xia, Shui-Li; Yang, Qian; Wang, Xiao; Yu, Shaoxiong; Luo, Yuzi; Sun, Yuan; Zhu, Yan; Munir, Muhammad

    2016-01-01

    ABSTRACT Many viruses trigger the type I interferon (IFN) pathway upon infection, resulting in the transcription of hundreds of interferon-stimulated genes (ISGs), which define the antiviral state of the host. Classical swine fever virus (CSFV) is the causative agent of classical swine fever (CSF), a highly contagious viral disease endangering the pig industry in many countries. However, anti-CSFV ISGs are poorly documented. Here we screened 20 ISGs that are commonly induced by type I IFNs against CSFV in lentivirus-delivered cell lines, resulting in the identification of guanylate-binding protein 1 (GBP1) as a potent anti-CSFV ISG. We observed that overexpression of GBP1, an IFN-induced GTPase, remarkably suppressed CSFV replication, whereas knockdown of endogenous GBP1 expression by small interfering RNAs significantly promoted CSFV growth. Furthermore, we demonstrated that GBP1 acted mainly on the early phase of CSFV replication and inhibited the translation efficiency of the internal ribosome entry site of CSFV. In addition, we found that GBP1 was upregulated at the transcriptional level in CSFV-infected PK-15 cells and in various organs of CSFV-infected pigs. Coimmunoprecipitation and glutathione S-transferase (GST) pulldown assays revealed that GBP1 interacted with the NS5A protein of CSFV, and this interaction was mapped in the N-terminal globular GTPase domain of GBP1. Interestingly, the K51 of GBP1, which is crucial for its GTPase activity, was essential for the inhibition of CSFV replication. We showed further that the NS5A-GBP1 interaction inhibited GTPase activity, which was critical for its antiviral effect. Taking our findings together, GBP1 is an anti-CSFV ISG whose action depends on its GTPase activity. IMPORTANCE Classical swine fever virus (CSFV) is the causative agent of classical swine fever (CSF), an economically important viral disease affecting the pig industry in many countries. To date, only a few host restriction factors against CSFV

  16. 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

    Host–virus interactions play an important role for the clinical outcome of classicalswinefevervirus (CSFV) infections in pigs. Strain virulence, host characteristics and environment are all factors that markedly influence disease severity. We tested CSFV strains of varying virulence in an experim...

  17. Rapid Detection Co-infections of Classical Swine Fever Virus and Porcine Reproductive and Respiratory Syndrome Virus by One-step Multiplex RT-PCR

    Institute of Scientific and Technical Information of China (English)

    TIAN Hong; WU Jinyan; YAN Chen; SHANG Youjun; YIN Shuanghui; LIU Xiangtao

    2011-01-01

    Classical swine fever virus (CSFV) and porcine reproductive and respiratory syndrome virus (PRRSV) have caused immense economic loss in the pig industry and are considered to be the two most important infectious diseases of pigs in the world A multiplex reverse transcription polymerase chain reaction (multiplex RT-PCR) was developed for CSFV and PRRSV co-infections or infections, respectively. A set of two pairs of primer was designed based on the sequence of nonstructural protein NS54B of CSFV and ORF7 gene of PRRSV. The diagnostic accuracy of multiplex RT-PCR assay was evaluated by using 56 field clinical samples by multiplex RT-PCR, single RT-PCR and sequence analysis; and the specificity of multiplex PCR was verified by using constructed plasmids containing the specific viral target fragments of PRRSV and CSFV, respectively. The results indicated that this assay could reliably differentiate PRRSV and CSFV in co-infection samples. The multiplex RT-PCR developed in this study might provide a new avenue to the rapid the detection of CSFV and PRRSV in one reaction.

  18. The control of classical swine fever in wild boar

    OpenAIRE

    Moennig, Volker

    2015-01-01

    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...

  19. Local spread of classical swine fever upon virus introduction into The Netherlands: Mapping of areas at high risk

    Directory of Open Access Journals (Sweden)

    Hagenaars Thomas J

    2008-02-01

    Full Text Available Abstract Background In the recent past, the introduction of Classical Swine Fever Virus (CSFV followed by between-herd spread has given rise to a number of large epidemics in The Netherlands and Belgium. Both these countries are pork-exporting countries. Particularly important in these epidemics has been the occurrence of substantial "neighborhood transmission" from herd to herd in the presence of base-line control measures prescribed by EU legislation. Here we propose a calculation procedure to map out "high-risk areas" for local between-herd spread of CSFV as a tool to support decision making on prevention and control of CSFV outbreaks. In this procedure the identification of such areas is based on an estimated inter-herd distance dependent probability of neighborhood transmission or "local transmission". Using this distance-dependent probability, we derive a threshold value for the local density of herds. In areas with local herd density above threshold, local transmission alone can already lead to epidemic spread, whereas in below-threshold areas this is not the case. The first type of area is termed 'high-risk' for spread of CSFV, while the latter type is termed 'low-risk'. Results As we show for the case of The Netherlands, once the distance-dependent probability of local transmission has been estimated from CSFV outbreak data, it is possible to produce a map of the country in which areas of high-risk herds and of low-risk herds are identified. We made these maps even more informative by estimating border zones between the two types of areas. In these border zones the risk of local transmission of infection to a nearby high-risk area exceeds a certain level. Conclusion The risk maps provide an easily understandable visualization of the spatial heterogeneities in transmission risk. They serve as a tool for area-specific designs of control strategies, and possibly also for spatial planning of areas where livestock farming is allowed. Similar

  20. Screwworms, Cochliomyia hominivorax, reared for mass release do not carry and spread foot-and-mouth disease virus and classical swine fever virus

    Science.gov (United States)

    Transporting live screwworms Cochliomyia hominivorax Coquerel for developing new strains from countries where foot-and-mouth disease (FMD) and classical swine fever (CSF) are endemic, to the mass rearing facilities in Mexico and Panama may introduce these exotic diseases. This study was conducted to...

  1. Development and standardization of an indirect ELISA for the serological diagnosis of classical swine fever

    OpenAIRE

    Paredes Julio Cesar Muñoz; Oliveira Liliane Guimarães; Braga Alexandre de Carvalho; Trevisol Iara Maria; Roehe Paulo Michel

    1999-01-01

    An indirect enzyme linked immunoassay (ELISA-I) was developed and standardized for the serological diagnosis of classical swine fever (CSF). For the comparison, nine hundred and thirty-seven swine serum samples were tested by serum neutralization followed by immunoperoxidase staining (NPLA), considered as the standard. Of these, 223 were positive and 714 negative for neutralizing antibodies to classical swine fever virus (CSFV). In relation to the NPLA, the ELISA-I presented a 98.2% sensitivi...

  2. Classic swine fever virus NS2 protein leads to the induction of cell cycle arrest at S-phase and endoplasmic reticulum stress

    Directory of Open Access Journals (Sweden)

    He Lei

    2010-01-01

    Full Text Available Abstract Background Classical swine fever (CSF caused by virulent strains of Classical swine fever virus (CSFV is a haemorrhagic disease of pigs, characterized by disseminated intravascular coagulation, thrombocytopoenia and immunosuppression, and the swine endothelial vascular cell is one of the CSFV target cells. In this report, we investigated the previously unknown subcellular localization and function of CSFV NS2 protein by examining its effects on cell growth and cell cycle progression. Results Stable swine umbilical vein endothelial cell line (SUVEC expressing CSFV NS2 were established and showed that the protein localized to the endoplasmic reticulum (ER. Cellular analysis revealed that replication of NS2-expressing cell lines was inhibited by 20-30% due to cell cycle arrest at S-phase. The NS2 protein also induced ER stress and activated the nuclear transcription factor kappa B (NF-κB. A significant increase in cyclin A transcriptional levels was observed in NS2-expressing cells but was accompanied by a concomitant increase in the proteasomal degradation of cyclin A protein. Therefore, the induction of cell cycle arrest at S-phase by CSFV NS2 protein is associated with increased turnover of cyclin A protein rather than the down-regulation of cyclin A transcription. Conclusions All the data suggest that CSFV NS2 protein modulate the cellular growth and cell cycle progression through inducing the S-phase arrest and provide a cellular environment that is advantageous for viral replication. These findings provide novel information on the function of the poorly characterized CSFV NS2 protein.

  3. Screening of cellular proteins that interact with the classical swine fever virus non-structural protein 5A by yeast two-hybrid analysis

    Indian Academy of Sciences (India)

    Chengcheng Zhang; Lei He; Kai Kang; Heng Chen; Lei Xu; Yanming Zhang

    2014-03-01

    Classical swine fever virus (CSFV), the pathogen of classical swine fever (CSF), causes severe hemorrhagic fever and vascular necrosis in domestic pigs and wild boar. A large number of evidence has proven that non-structural 5A (NS5A) is not only a very important part of viral replication complex, but also can regulate host cell’s function; however, the underlying mechanisms remain poorly understood. In the current study, aiming to find more clues in understanding the molecular mechanisms of CSFV NS5A’s function, the yeast two-hybrid (Y2H) system was adopted to screen for CSFV NS5A interactive proteins in the cDNA library of the swine umbilical vein endothelial cell (SUVEC). Alignment with the NCBI database revealed 16 interactive proteins: DDX5, PSMC3, NAV1, PHF5A, GNB2L1, CSDE1, HSPA8, BRMS1, PPP2R3C, AIP, TMED10, POLR1C, TMEM70, METAP2, CHORDC1 and COPS6. These proteins are mostly related to gene transcription, protein folding, protein degradation and metabolism. The interactions detected by the Y2H system should be considered as preliminary results. Since identifying novel pathways and host targets, which play essential roles during infection, may provide potential targets for therapeutic development. The finding of proteins obtained from the SUVEC cDNA library that interact with the CSFV NS5A protein provide valuable information for better understanding the interactions between this viral protein and the host target proteins.

  4. Direct coating of culture medium from cells secreting classical swine fever virus E2 antigen on ELISA plates for detection of E2-specific antibodies.

    Science.gov (United States)

    Cheng, Ta-Chun; Pan, Chu-Hsiang; Chen, Chien-Shu; Chuang, Kuo-Hsiang; Chuang, Chih-Hung; Huang, Chien-Chaio; Chu, Yu-Yi; Yang, Ya-Chun; Chu, Pei-Yu; Kao, Chien-Han; Hsieh, Yuan-Chin; Cheng, Tian-Lu

    2015-07-01

    The envelope glycoprotein E2 of classical swine fever virus (CSFV) is widely used as a marker for measuring vaccine efficacy and antibody titer. The glycosylation profile of E2 may affect the immunogenicity of the vaccine and the timing of re-vaccination. In this study, a human embryonic kidney cell line was used to secrete fully-glycosylated CSFV E2, which was then coated onto ELISA plates without purification or adjustment. The resulting E2-secreting medium-direct-coating (E2-mDc) ELISA was successfully used to measure anti-E2 antibody titers in vaccinated and field pig sera samples. Compared with a virus neutralization test (as standard), the E2-mDc ELISA was found to be more accurate (90%) than a commercial CSFV antibody diagnostic kit (62%). In conclusion, the mammalian cell-secreted antigen can provide cheap, accurate and effective assays for vaccine efficacy and disease diagnoses. PMID:25975854

  5. A comparison of the impact of Shimen and C strains of classical swine fever virus on Toll-like receptor expression.

    Science.gov (United States)

    Cao, Zhi; Guo, Kangkang; Zheng, Minping; Ning, Pengbo; Li, Helin; Kang, Kai; Lin, Zhi; Zhang, Chengcheng; Liang, Wulong; Zhang, Yanming

    2015-07-01

    Classical swine fever is one of the most important swine diseases worldwide and has tremendous socioeconomic impact. In this study, we focused on the signalling pathways of Toll-like receptors (TLRs) because of their roles in the detection and response to viral infections. To this end, two classical swine fever virus (CSFV) strains, namely the highly virulent CSFV Shimen strain and the avirulent C strain (a vaccine strain), were employed, and the expression of 19 immune effector genes was analysed by real-time PCR, Western blot analyses, ELISA and flow cytometry analyses. In vitro experiments were conducted with porcine monocyte-derived macrophages (pMDMs). The results showed that the mRNA and protein levels of TLR2, TLR4 and TLR7 were upregulated in response to CSFV infection, but TLR3 remained unchanged, and was downregulated after infection with the C strain and the Shimen virus, respectively. Furthermore, TLR3-mediated innate immune responses were inhibited in Shimen-strain-infected pMDMs by stimulation with poly(I : C). Accordingly, comprehensive analyses were performed to detect TLR-dependent cytokine responses and the activation of TLR signalling elements. CSFV infection induced mitogen-activated protein kinase activation, but did not elicit NFκB activation, thereby affecting the production of pro-inflammatory cytokines. The Shimen strain infection resulted in a significant activation of IFN regulatory factor IRF7 and suppression of IRF3. These data provided clues for understanding the effect of CSFV infection on the TLR-mediated innate immune response and associated pathological changes. PMID:25805409

  6. Sequencing and rescuing a highly virulent classical swine fever virus: Chinese strain cF114 from a full-length cDNA clone

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The complete nucleotide sequence of classical swine fever virus (CSFV) strain cF114 (F114 strain propa- gated on PK-15 cells) was cloned by RT-PCR. The analyses of nucleotide and amino acids identity between cF114 and F114, Brescia, Alfort or C strain were 99.41%, 96.80%, 86.03%, 95.70% and 99.28%, 98.54%, 93.33%, 97.41% re- spectively. The cDNA fragments with correct sequence were ligated into a full-length cDNA and inserted into pMC18 plasmid (pMC12297). A full-length infectious viral RNA was synthesized by runoff transcription and transfected to PK15 cells. Viruses were recovered from transfected cells which wese titrated on PK-15 cells by endpoint dilution and indirect immunofluorescence with a CSFV-specific monoclonal antibody. The antigenicity and replication kinetics of the plasmid-derived virus (vM12297) were similar to the parental virus in vitro. The E01 or E2 gene was replaced with the genes from strain C and the pM/CE01 and pM/CE2 with chimeric full-length cDNA of cF114 were generated. The infectious viruses were obtained from pM/CE01 and pM/CE2. Both of the chimeric viruses can infect PK-15, SK- 6 and primary testicle cell of swine. The chimeric viruses can grow to a titer of 8×105 F-PFU/mL. These results are very important for understanding the genes related to the CSFV propagation and pathogenesis.

  7. Risk factors associated with occurrence of African swine fever outbreaks in smallholder pig farms in four districts along the Uganda-Kenya border.

    Science.gov (United States)

    Nantima, Noelina; Ocaido, Michael; Ouma, Emily; Davies, Jocelyn; Dione, Michel; Okoth, Edward; Mugisha, Anthony; Bishop, Richard

    2015-03-01

    A cross-sectional survey was carried out to assess risk factors associated with occurrence of African swine fever (ASF) outbreaks in smallholder pig farms in four districts along Kenya-Uganda border. Information was collected by administering questionnaires to 642 randomly selected pig households in the study area. The study showed that the major risk factors that influenced ASF occurrence were purchase of pigs in the previous year (p pigs with swill (p pig production types were identified based on production characteristics that were found to differ significantly between districts. The most vulnerable cluster to ASF was households with the highest reported number of ASF outbreaks and composed of those that practiced free range at least some of the time. The majority of the households in this cluster were from Busia district in Uganda. On the other hand, the least vulnerable cluster to ASF composed of households that had the least number of pig purchases, minimal swill feeding, and less treatment for internal and external parasites. The largest proportion of households in this cluster was from Busia district Kenya. The study recommended the need to sensitize farmers to adopt proper biosecurity practices such as total confinement of pigs, treatment of swill, isolation of newly purchased pigs for at least 2 weeks, and provision of incentives for farmers to report suspected outbreaks to authorities and rapid confirmation of outbreaks. PMID:25616986

  8. Rift Valley Fever Virus

    Science.gov (United States)

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

  9. Different RNA splicing mechanisms contribute to diverse infective outcome of classical swine fever viruses of differing virulence: insights from the deep sequencing data in swine umbilical vein endothelial cells.

    Science.gov (United States)

    Ning, Pengbo; Zhou, Yulu; Liang, Wulong; Zhang, Yanming

    2016-01-01

    Molecular mechanisms underlying RNA splicing regulation in response to viral infection are poorly understood. Classical swine fever (CSF), one of the most economically important and highly contagious swine diseases worldwide, is caused by classical swine fever virus (CSFV). Here, we used high-throughput sequencing to obtain the digital gene expression (DGE) profile in swine umbilical vein endothelial cells (SUVEC) to identify different response genes for CSFV by using both Shimen and C strains. The numbers of clean tags obtained from the libraries of the control and both CSFV-infected libraries were 3,473,370, 3,498,355, and 3,327,493 respectively. In the comparison among the control, CSFV-C, and CSFV-Shimen groups, 644, 158, and 677 differentially expressed genes (DEGs) were confirmed in the three groups. Pathway enrichment analysis showed that many of these DEGs were enriched in spliceosome, ribosome, proteasome, ubiquitin-mediated proteolysis, cell cycle, focal adhesion, Wnt signalling pathway, etc., where the processes differ between CSFV strains of differing virulence. To further elucidate important mechanisms related to the differential infection by the CSFV Shimen and C strains, we identified four possible profiles to assess the significantly expressed genes only by CSFV Shimen or CSFV C strain. GO analysis showed that infection with CSFV Shimen and C strains disturbed 'RNA splicing' of SUVEC, resulting in differential 'gene expression' in SUVEC. Mammalian target of rapamycin (mTOR) was identified as a significant response regulator contributed to impact on SUVEC function for CSFV Shimen. This computational study suggests that CSFV of differing virulence could induce alterations in RNA splicing regulation in the host cell to change cell metabolism, resulting in acute haemorrhage and pathological damage or infectious tolerance. PMID:27330868

  10. 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)

    E2, along with Erns 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, 818CPIGWTGVIEC828, 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 818CPIGWTGVIEC828 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

  11. 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.

  12. Characterization of the Antigenicity and Immunogenicity of the Escherichia Coli Produced Rnase Domain of the Classical Swine Fever Virus Glycoprotein Erns

    Institute of Scientific and Technical Information of China (English)

    QI Yun; LIU Lianchi; WANG Ji; CHEN Yinghua

    2009-01-01

    Erns is a highly glycosylated envelope protein of classical swine fever virus (CSFV) with RNase activity. Erns can induce neutralizing antibodies and provide immune protection against CSFV infection. In this study, the RNase domain of the Erns was produced in Escherichia coli. Its reactivity with CSFV-positive sera and its ability to induce antibodies and to provide protective immunity were then investigated. The serological tests showed that the prokaryotically expressed RNase domain of the Erns retained its antigenicity and induced high titers of humoral responses. However, only partial protection and a limited amount of neutralizing antibodies were demonstrated by an in vitro neutralization test and an immunization/challenge test. The results suggest that other essential factors rather than simply enhancing the immunogenicity of Erns should be taken into consideration when Erns is enrolled as one of the components of a candidate vaccine.

  13. Viremia and antibody response of small African and laboratory animals to Crimean-Congo hemorrhagic fever virus infection.

    Science.gov (United States)

    Shepherd, A J; Leman, P A; Swanepoel, R

    1989-05-01

    Eleven species of small African wild mammals, laboratory rabbits, guinea pigs, and Syrian hamsters were infected with Crimean-Congo hemorrhagic fever (CCHF) virus. Low-titered viremia followed by development of antibody was observed in scrub hares (Lepus saxatilis), Cape ground squirrels (Xerus inauris), red veld rats (Aethomys chrysophilus), white tailed rats (Mystromys albicaudatus), bushveld gerbils (Tatera leucogaster), striped mice (Rhabdomys pumilio), and guinea pigs. The maximum viremic titer in 4 scrub hares was 10(1.7-4.2) 50% mouse lethal doses/ml. Viremia was detected in 1/17 infected laboratory rabbits. Antibody response was only detected in South African hedgehogs (Atelerix frontalis), highveld gerbils (T. brantsii), Namaqua gerbils (Desmodillus auricularis), 2 species of multimammate mouse (Mastomys natalensis and M. coucha), and Syrian hamsters. The results of the study indicate that a proportion of infected scrub hares develop CCHF viremia of an intensity shown in the Soviet Union to be sufficient for infection of feeding immature ixodid ticks, but that South African hedgehogs and wild rodents are unlikely to be of importance as maintenance hosts of the virus in southern Africa. PMID:2499205

  14. Construction of infectious cDNA clone derived from a classical swine fever virus field isolate in BAC vector using in vitro overlap extension PCR and recombination.

    Science.gov (United States)

    Kamboj, Aman; Saini, Mohini; Rajan, Lekshmi S; Patel, Chhabi Lal; Chaturvedi, V K; Gupta, Praveen K

    2015-12-15

    To develop reverse genetics system of RNA viruses, cloning of full-length viral genome is required which is often challenging due to many steps involved. In this study, we report cloning of full-length cDNA from an Indian field isolate (CSFV/IVRI/VB-131) of classical swine fever virus (CSFV) using in vitro overlap extension PCR and recombination which drastically reduced the number of cloning steps. The genome of CSFV was amplified in six overlapping cDNA fragments, linked by overlap extension PCR and cloned in a bacterial artificial chromosome (BAC) vector using in vitro recombination method to generate full-length cDNA clone. The full-length CSFV cDNA clone was found stable in E. coli Stellar and DH10B cells. The full-length RNA was transcribed in vitro using T7 RNA polymerase and transfected in PK15 cells using Neon-tip electroporator to rescue infectious CSFV. The progeny CSFV was propagated in PK15 cells and found indistinguishable from the parent virus. The expression of CSFV proteins were detected in cytoplasm of PK15 cells infected with progeny CSFV at 72 h post-infection. We concluded that the in vitro overlap extension PCR and recombination method is useful to construct stable full-length cDNA clone of RNA virus in BAC vector. PMID:26478540

  15. Serum antibodies directed against classical swine fever virus and other pestiviruses in wild boar (Sus scrofa) in the Republic of Croatia.

    Science.gov (United States)

    Roic, B; Depner, K R; Jemersic, L; Lipej, Z; Cajavec, S; Toncic, J; Lojkic, M; Mihauevic, Z

    2007-04-01

    The presence of serum antibodies directed against classical swine fever (CSF) virus and other pestiviruses among the wild boar (Sus scrofa) population in Croatia was investigated. During 2003, serum samples from 214 wild boars were collected in 10 hunting areas in the continental part of the country. The sera were examined by enzyme immunoassay (ELISA) and in the virus neutralization test (VNT). Out of 214 sera tested 111 (51.87 %) were positive by ELISA and regarding neutralising antibodies, against CSFV 75 (35.05 %) samples were positive. In the VNT with the C-strain (conventional live vaccine strain China) and the strain Uelzen were used. Samples were also tested for neutralizing antibodies against border disease virus (BDV) using the strain 137/4 and against bovine viral diarrhoea virus (BVDV) using the NADL strain. Neutralizing antibodies against the C-strain were detected in 36 sera (16.82 %), against strain Uelzen in 17 sera (7.94 %) and in 22 sera (10.28 %) against both strains. In five sera (2.33 %) neutralizing antibodies against BVDV and BDV were found. PMID:17484502

  16. Diagnosis of Mixed Infection of Classical Swine Fever Virus (CSFV) and Porcine Reproductive and Respiratory Syndrome Virus (PRRSV)%猪瘟和猪繁殖与呼吸综合征病毒混合感染的诊断

    Institute of Scientific and Technical Information of China (English)

    向智龙; 欧德渊; 程振涛; 周碧君; 冯会利; 刘芳; 冉光鑫

    2011-01-01

    2009年3月贵州省某猪场送检病猪3例,为确诊病因,进行了流行病学调查,实验室剖检病变观察,细菌学、荧光抗体和RT-PCR检测.经流行病学调查和剖检病变观察,该病例为疑似猪繁殖与呼吸综合征病毒、猪瘟病毒感染所致;该病例细菌分离鉴定结果为阴性,猪瘟直接荧光抗体检测结果为阳性,猪繁殖与呼吸综合征病毒和猪瘟病毒RT-PCR核酸检测为阳性.表明,该病例为猪瘟病毒和猪繁殖与呼吸综合征病毒混合感染.%The pathogenesis of three sick pigs from the pig farm was determined by epidemiological survey, autopsy pathological observation; bacteriological detection, fluorescence antibody test and RTPCR. The results showed that three pigs may be infected by classical swine fever (CSF) and porcine reproductive and respiratory syndrome (PRRS), the bacterium isolated from three sick pigs was negative,the direct fluorescence antibody test of classical swine fever was positive, and the classical swine fever (CSF) and porcine reproductive and respiratory syndrome were positive by RT-PCR test, which indicates that three sick pigs were infected by virus of classical swine fever (CSF) and porcine reproductive and respiratory syndrome.

  17. Identification of two internal signal peptide sequences: critical for classical swine fever virus non-structural protein 2 to trans-localize to the endoplasmic reticulum

    Directory of Open Access Journals (Sweden)

    Zhang Yan-ming

    2011-05-01

    Full Text Available Abstract Background The membrane topology and molecular mechanisms for endoplasmic reticulum (ER localization of classical swine fever virus (CSFV non-structural 2 (NS2 protien is unclear. We attempted to elucidate the subcellular localization, and the molecular mechanisms responsible for the localization of this protein in our study. The NS2 gene was amplified by reverse transcription polymerase chain reaction, with the transmembrane region and hydrophilicity of the NS2 protein was predicted by bioinformatics analysis. Twelve cDNAs of the NS2 gene were amplified by the PCR deletion method and cloned into a eukaryotic expression vector, which was transfected into a swine umbilical vein endothelial cell line (SUVEC. Subcellular localization of the NS2 protein was characterized by confocal microscopy, and western blots were carried out to analyze protein expression. Results Our results showed that the -NH2 terminal of the CSFV NS2 protein was highly hydrophobic and the protein localized in the ER. At least four transmembrane regions and two internal signal peptide sequences (amino acids103-138 and 220-262 were identified and thought to be critical for its trans-localization to the ER. Conclusions This is the first study to identify the internal signal peptide sequences of the CSFV NS2 protein and its subcellular localization, providing the foundation for further exploration of this protein's function of this protein and its role in CSFV pathogenesis.

  18. Rift Valley fever virus infection in African Buffalo (Syncerus caffer) herds in rural South Africa: Evidence of interepidemic transmission

    Science.gov (United States)

    LaBeaud, A.D.; Cross, P.C.; Getz, W.M.; Glinka, A.; King, C.H.

    2011-01-01

    Rift Valley fever virus (RVFV) is an emerging biodefense pathogen that poses significant threats to human and livestock health. To date, the interepidemic reservoirs of RVFV are not well defined. In a longitudinal survey of infectious diseases among African buffalo during 2000-2006, 550 buffalo were tested for antibodies against RVFV in 820 capture events in 302 georeferenced locations in Kruger National Park, South Africa. Overall, 115 buffalo (21%) were seropositive. Seroprevalence of RVFV was highest (32%) in the first study year, and decreased progressively in subsequent years, but had no detectable impact on survival. Nine (7%) of 126 resampled, initially seronegative animals seroconverted during periods outside any reported regional RVFV outbreaks. Seroconversions for RVFV were detected in significant temporal clusters during 2001-2003 and in 2004. These findings highlight the potential importance of wildlife as reservoirs for RVFV and interepidemic RVFV transmission in perpetuating regional RVFV transmission risk. Copyright ?? 2011 by The American Society of Tropical Medicine and Hygiene.

  19. 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

    be rescued only from some of our BAC constructs whereas others are not replication competent. To further analyze this discrepancy we have completely sequenced selected pestivirus BAC DNAs using a 454 Genome Sequencer FLX to evaluate the number/kind of deviations in the cloned genome sequences. In addition......, we have sequenced the full genome cDNA fragments used for the BACs by the same approach. This enables us to evaluate in more detail the nature of nucleotide changes in the pestivirus BACs that lead to lack of replicationcompetence and/or virus rescue. Additionally, detailed knowledge of the genomic...

  20. The 3'-terminal hexamer sequence of classical swine fever virus RNA plays a role in negatively regulating the IRES-mediated translation.

    Directory of Open Access Journals (Sweden)

    Shih-Wei Huang

    Full Text Available The 3' untranslated region (UTR is usually involved in the switch of the translation and replication for a positive-sense RNA virus. To understand the 3' UTR involved in an internal ribosome entry site (IRES-mediated translation in Classical swine fever virus (CSFV, we first confirmed the predicted secondary structure (designated as SLI, SLII, SLIII, and SLIV by enzymatic probing. Using a reporter assay in which the luciferase expression is under the control of CSFV 5' and 3' UTRs, we found that the 3' UTR harbors the positive and negative regulatory elements for translational control. Unlike other stem loops, SLI acts as a repressor for expression of the reporter gene. The negative cis-acting element in SLI is further mapped to the very 3'-end hexamer CGGCCC sequence. Further, the CSFV IRES-mediated translation can be enhanced by the heterologous 3'-ends such as the poly(A or the 3' UTR of Hepatitis C virus (HCV. Interestingly, such an enhancement was repressed by flanking this hexamer to the end of poly(A or HCV 3' UTR. After sequence comparison and alignment, we have found that this hexamer sequence could hypothetically base pair with the sequence in the IRES IIId1, the 40 S ribosomal subunit binding site for the translational initiation, located at the 5' UTR. In conclusion, we have found that the 3'-end terminal sequence can play a role in regulating the translation of CSFV.

  1. Intracellular membrane association of the N-terminal domain of classical swine fever virus NS4B determines viral genome replication and virulence.

    Science.gov (United States)

    Tamura, Tomokazu; Ruggli, Nicolas; Nagashima, Naofumi; Okamatsu, Masatoshi; Igarashi, Manabu; Mine, Junki; Hofmann, Martin A; Liniger, Matthias; Summerfield, Artur; Kida, Hiroshi; Sakoda, Yoshihiro

    2015-09-01

    Classical swine fever virus (CSFV) causes a highly contagious disease in pigs that can range from a severe haemorrhagic fever to a nearly unapparent disease, depending on the virulence of the virus strain. Little is known about the viral molecular determinants of CSFV virulence. The nonstructural protein NS4B is essential for viral replication. However, the roles of CSFV NS4B in viral genome replication and pathogenesis have not yet been elucidated. NS4B of the GPE-  vaccine strain and of the highly virulent Eystrup strain differ by a total of seven amino acid residues, two of which are located in the predicted trans-membrane domains of NS4B and were described previously to relate to virulence, and five residues clustering in the N-terminal part. In the present study, we examined the potential role of these five amino acids in modulating genome replication and determining pathogenicity in pigs. A chimeric low virulent GPE- -derived virus carrying the complete Eystrup NS4B showed enhanced pathogenicity in pigs. The in vitro replication efficiency of the NS4B chimeric GPE-  replicon was significantly higher than that of the replicon carrying only the two Eystrup-specific amino acids in NS4B. In silico and in vitro data suggest that the N-terminal part of NS4B forms an amphipathic α-helix structure. The N-terminal NS4B with these five amino acid residues is associated with the intracellular membranes. Taken together, this is the first gain-of-function study showing that the N-terminal domain of NS4B can determine CSFV genome replication in cell culture and viral pathogenicity in pigs. PMID:26018962

  2. Enhanced expression of the Erns protein of classical swine fever virus in yeast and its application in an indirect enzyme-linked immunosorbent assay for antibody differentiation of infected from vaccinated animals.

    Science.gov (United States)

    Luo, Yuzi; Li, Lin; Austermann-Busch, Sophia; Dong, Mei; Xu, Jingjing; Shao, Lina; Lei, Jianlin; Li, Na; He, Wen-Rui; Zhao, Bibo; Li, Su; Li, Yongfeng; Liu, Lihong; Becher, Paul; Sun, Yuan; Qiu, Hua-Ji

    2015-09-15

    Classical swine fever (CSF), caused by classical swine fever virus (CSFV), is a devastating disease of swine worldwide. Although a mandatory vaccination with the modified live vaccine C-strain has been implemented in China for decades, CSF remains a serious threat to the swine industry. To facilitate the control and eradication of CSF in China, the E2-based marker vaccine rAdV-SFV-E2, an adenovirus-delivered, alphavirus replicon-vectored vaccine, has been developed. Accordingly, an accompanying discriminatory test that allows differentiating infected from vaccinated animals (DIVA) is required. Here, the enhanced expression of E(rns) protein of CSFV was achieved in the methyltropic yeast Pichia pastoris by codon-optimization of the E(rns) gene, and an indirect enzyme-linked immunosorbent assay (iELISA) based on the yeast-expressed E(rns) (yE(rns)) was developed and evaluated. The optimized iELISA was able to detect CSFV-specific antibodies in the serum samples from the CSFV-infected pigs as early as 6 days post-infection, and discriminate the CSFV-infected pigs from those vaccinated with rAdV-SFV-E2. The iELISA was evaluated using a panel of swine sera, and showed comparable sensitivity (94.6%) and specificity (97.1%), and the consistence rates with the virus neutralization test were 96.8% for CSFV-infected swine sera, 83.3% for C-strain-vaccinated swine sera, and 95.0% for field swine sera. In addition, the iELISA showed higher sensitivity (90.4%) compared with PrioCHECK CSFV E(rns) (59.6%). Taken together, the yE(rns)-based iELISA is specific and sensitive, representing a promising DIVA test for E2-based marker vaccines against CSF. PMID:26005003

  3. The Situation of Bovine Viral Diarrhea Virus Pollution in Swine Fever Vaccine and Research Progress of its Detection Method%牛病毒性腹泻病毒在猪瘟疫苗中的污染情况及其检测方法的研究进展

    Institute of Scientific and Technical Information of China (English)

    毛晓娜; 缪芬芳; 季伟

    2013-01-01

    牛病毒性腹泻病毒(bovine viral diarrhea virus,BVDV)和猪瘟病毒(classical swine fever virus,CSFV)同属黄病毒科瘟病毒属,猪瘟疫苗中污染BVDV可引起免疫失败.但由于两者在病毒粒子结构、基因组结构和抗原特性等方面均很接近,在血清学上存在交叉反应,因此难以检测猪瘟疫苗中污染的BVDV.文章对BVDV在猪瘟疫苗中的污染情况和检测方法进行了论述,旨在为猪瘟疫苗污染BVDV的检测提供理论基础.%Bovine viral diarrhea virus(BVDV) and classical swine fever virus(CSFV) both belong to Pestivirus, Flaviviri-dae. It can cause immune failure by BVDV pollution in swine fever vaccine. But because of the similar of their virus structure, genome structure, and antigen characteristics, they have cross reaction. So it is difficult to detect the BVDV pollution in swine fever vaccine. In this paper, we have discussed the situation of BVDV pollution in swine fever vaccine and its detection methods, aiming to provide theoretical basis for detecting BVDV pollution in swine fever vaccines.

  4. Evaluation of bait acceptance by wild boar and non-target species - test of different distribution modalities and seasonal variations - implication for oral vaccination efficiency against classical swine fever virus

    OpenAIRE

    Sage, M.; Hubert, P.; S. Rossi

    2011-01-01

    Field assessment of the proportion of target and non-target individuals that consume baits is crucial to evaluate and optimize the cost-efficacy of a baiting campaign. In our study, different pre-baiting and baiting systems were tested at a long time scale (12 months) to try to improve vaccination efficiency of wild boars against classical swine fever virus. Evaluation of seasonal variation in natural food resources (competition with bait consumption) and life cycle succession of wild boar fr...

  5. 免疫亲和层析法快速纯化猪瘟病毒抗体%Rapid Purification of Antibody against Classical Swine Fever Virus by Immunoaffinity Chromatography

    Institute of Scientific and Technical Information of China (English)

    封琳; 王桂珍; 李阳; 李任强

    2011-01-01

    目的 应用免疫亲和层析技术快速纯化猪瘟病毒抗体.方法 将猪瘟病毒接种于猪传代肾细胞PK-15中培养,收获并纯化猪瘟病毒,将其与环氧氯丙烷活化的Sepharose-4B偶联,制备免疫亲和层析柱,从猪瘟病毒高免疫猪血清中纯化猪瘟病毒抗体,分别应用SDS-PAGE和ELISA进行抗体纯度和活性检测.结果 自制免疫亲和层析柱的偶联率为0.36 mg抗原/g载体;纯化的猪瘟病毒抗体纯度高,活性强,抗体回收率占猪血清总蛋白的2.45%.结论 已建立了成本低、可快速有效纯化猪瘟病毒抗体的免疫亲和层析法.%Objective To purify the antibody against classical swine fever virus by immunoaffinity chromatography. Methods Classical swine fever virus was inoculated to subcultured pig kidney PK-15 cells and incubated. The harvested virus was purified and coupled with epichlorohydrin-activated Sepharose-4B to prepare immunoaffinity chromatographic column by which the antibody against classical swine fever virus was purified from hyperimmune sera of pigs and determined for purity and activity by SDS-PAGE and ELISA respectively. Results The coupling rate of prepared immunoaffinity chromatography column was 0. 36 mg antigen / g carrier. The purified antibody against classical swine fever virus showed high purity and activity, of which the recovery rate of 2. 45% of total serum protein. Conclusion A low-cost, rapid and effective immunoaffinity chromatographic method for purification of antibody a-gainst classical swine fever virus was successfully developed.

  6. Safety and immunogenicity of a gE/gI/TK gene-deleted pseudorabies virus variant expressing the E2 protein of classical swine fever virus in pigs.

    Science.gov (United States)

    Lei, Jian-Lin; Xia, Shui-Li; Wang, Yimin; Du, Mingliang; Xiang, Guang-Tao; Cong, Xin; Luo, Yuzi; Li, Lian-Feng; Zhang, Lingkai; Yu, Jiahui; Hu, Yonghao; Qiu, Hua-Ji; Sun, Yuan

    2016-06-01

    Classical swine fever (CSF) and pseudorabies (PR) are both major infectious diseases of pigs, causing enormous economic losses to the swine industry in many countries. A marker vaccine that enables differentiation of infected from vaccinated animals (DIVA) is highly desirable for control and eradication of these two diseases in endemic areas. Since late 2011, PR outbreaks have been frequently reported in many Bartha-K61-vaccinated pig farms in China. It has been demonstrated that a pseudorabies virus (PRV) variant with altered antigenicity and increased pathogenicity was responsible for the outbreaks. Previously, we showed that rPRVTJ-delgE/gI/TK, a gE/gI/TK-deleted PRV variant, was safe for susceptible animals and provided a complete protection against lethal PRV variant challenge, indicating that rPRVTJ-delgE/gI/TK can be used as an attractive vaccine vector. To develop a safe bivalent vaccine against CSF and PR, we generated a recombinant virus rPRVTJ-delgE/gI/TK-E2 expressing the E2 protein of classical swine fever virus (CSFV) based on rPRVTJ-delgE/gI/TK and evaluated its safety and immunogenicity in pigs. The results indicated that pigs (n=5) immunized with rPRVTJ-delgE/gI/TK-E2 of different doses did not exhibit clinical signs or viral shedding following immunization, the immunized pigs produced anti-PRV or anti-CSFV neutralizing antibodies and the pigs immunized with 10(6) or 10(5) TCID50 rPRVTJ-delgE/gI/TK-E2 were completely protected against the lethal challenge with either CSFV Shimen strain or variant PRV TJ strain. These findings suggest that rPRVTJ-delgE/gI/TK-E2 is a promising bivalent DIVA vaccine candidate against CSFV and PRV coinfections. PMID:27113530

  7. 古典猪瘟病毒基因组及ORF编码蛋白的结构和功能%The Genome and ORF Protein-coding Structure and Function of Classical Swine Fever Virus

    Institute of Scientific and Technical Information of China (English)

    朱小甫; 吴旭锦; 徐德乾; 杨萍

    2012-01-01

    Classical swine fever was a serious disease hazard pig industry, studying classical swine fever virus of molecular biology could reveal viral replication and pathogenesis, find key sites of immune protection, and lay the foundation for the development of new vaccines. This paper summarized recent classical swine fever virus genome research and related proteins, ma-ded for future research prospects.%古典猪瘟是严重危害养猪业发展的重要疫病之一,对古典猪瘟病毒的分子生物学研究能揭示病毒复制和致病机理,寻找免疫保护关键位点,为新型疫苗开发奠定基础.文章综述了近年对古典猪瘟病毒基因组和相关蛋白的研究成果,对以后的研究方向作了展望.

  8. 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

    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...

  9. Genetic diversity and positive selection analysis of classical swine fever virus envelope protein gene E2 in east China under C-strain vaccination

    Directory of Open Access Journals (Sweden)

    Dongfang eHu

    2016-02-01

    Full Text Available Classical swine fever virus (CSFV causes an economically important and highly contagious disease of pigs worldwide. C-strain vaccination is one of the most effective ways to contain this disease. Since 2014, sporadic CSF outbreaks have been occurring in some C-strain vaccinated provinces of China. To decipher the disease etiology, 25 CSFV E2 genes from 169 clinical samples were cloned and sequenced. Phylogenetic analyses revealed that all 25 isolates belonged to subgenotype 2.1. Twenty-three of the 25 isolates were clustered in a newly defined subgenotype, 2.1d, and shared some consistent molecular characteristics. To determine whether the complete E2 gene was under positive selection pressure, we used a site-by-site analysis to identify specific codons that underwent evolutionary selection, and seven positively selected codons were found. Three positively selected sites (amino acids 17, 34, and 72 were identified in antigenicity-relevant domains B/C of the amino-terminal half of the E2 protein. In addition, another positively selected site (amino acid 200 exhibited a polarity change from hydrophilic to hydrophobic, which may change the antigenicity and virulence of CSFV. The results indicate that the circulating CSFV strains in Shandong province were mostly clustered in subgenotype 2.1d. Moreover, the identification of these positively selected sites could help to reveal molecular determinants of virulence or pathogenesis, and to clarify the driving force of CSFV evolution in East China.

  10. eEF1A Interacts with the NS5A Protein and Inhibits the Growth of Classical Swine Fever Virus.

    Science.gov (United States)

    Li, Su; Feng, Shuo; Wang, Jing-Han; He, Wen-Rui; Qin, Hua-Yang; Dong, Hong; Li, Lian-Feng; Yu, Shao-Xiong; Li, Yongfeng; Qiu, Hua-Ji

    2015-08-01

    The NS5A protein of classical swine fever virus (CSFV) is involved in the RNA synthesis and viral replication. However, the NS5A-interacting cellular proteins engaged in the CSFV replication are poorly defined. Using yeast two-hybrid screen, the eukaryotic elongation factor 1A (eEF1A) was identified to be an NS5A-binding partner. The NS5A-eEF1A interaction was confirmed by coimmunoprecipitation, glutathione S-transferase (GST) pulldown and laser confocal microscopy assays. The domain I of eEF1A was shown to be critical for the NS5A-eEF1A interaction. Overexpression of eEF1A suppressed the CSFV growth markedly, and conversely, knockdown of eEF1A enhanced the CSFV replication significantly. Furthermore, eEF1A, as well as NS5A, was found to reduce the translation efficiency of the internal ribosome entry site (IRES) of CSFV in a dose-dependent manner, as demonstrated by luciferase reporter assay. Streptavidin pulldown assay revealed that eEF1A could bind to the CSFV IRES. Collectively, our results suggest that eEF1A interacts with NS5A and negatively regulates the growth of CSFV. PMID:26266418

  11. [Hsp70 Fused with the Envelope Glycoprotein E0 of Classical Swine Fever Virus Enhances Immune Responses in Balb/c Mice].

    Science.gov (United States)

    Xu, Qianqian; Zhang, Xiaomin; Jing, Jiao; Shi, Baojun; Wang, Shiqi; Zhou, Bin; Chen, Puyan

    2015-07-01

    Heat-shock protein (Hsp) 70 potentiates specific immune responses to some antigenic peptides fused to it. Here, the prokaryotic plasmids harboring the envelope glycoprotein E0 gene of classical swine fever virus (CSFV) and/or the Hsp70 gene of Haemophilus parasuis were constructed and expressed in Escherichia coli Rosseta 2(R2). The fusion proteins were then purified. Groups of Balb/c mice were immunized with these fusion proteins, respectively, and sera collected 7 days after the third immunization. Immune effects were determined via an enzyme-linked immunosorbent assay and flow cytometric analyses. E0-Hsp70 fusion protein and E0+Hsp70 mixture significantly improved the titer of E-specific antibody, levels of CD4+ and CD8+ T cells, and release of interferon-γ. These findings suggested that Hsp70 can significantly enhance the immune effects of the envelope glycoprotein E0 of CSFV, thereby laying the foundation of further application in pigs. PMID:26524908

  12. eEF1A Interacts with the NS5A Protein and Inhibits the Growth of Classical Swine Fever Virus

    Directory of Open Access Journals (Sweden)

    Su Li

    2015-08-01

    Full Text Available The NS5A protein of classical swine fever virus (CSFV is involved in the RNA synthesis and viral replication. However, the NS5A-interacting cellular proteins engaged in the CSFV replication are poorly defined. Using yeast two-hybrid screen, the eukaryotic elongation factor 1A (eEF1A was identified to be an NS5A-binding partner. The NS5A–eEF1A interaction was confirmed by coimmunoprecipitation, glutathione S-transferase (GST pulldown and laser confocal microscopy assays. The domain I of eEF1A was shown to be critical for the NS5A–eEF1A interaction. Overexpression of eEF1A suppressed the CSFV growth markedly, and conversely, knockdown of eEF1A enhanced the CSFV replication significantly. Furthermore, eEF1A, as well as NS5A, was found to reduce the translation efficiency of the internal ribosome entry site (IRES of CSFV in a dose-dependent manner, as demonstrated by luciferase reporter assay. Streptavidin pulldown assay revealed that eEF1A could bind to the CSFV IRES. Collectively, our results suggest that eEF1A interacts with NS5A and negatively regulates the growth of CSFV.

  13. Interleukin 10 Suppresses the Function of Mouse Bone Marrow-Derived Dendritic Cells Infected with Classical Swine Fever Virus C-Strain

    Directory of Open Access Journals (Sweden)

    Fu-Ying Zheng, Guo-Zhen Lin* and Zhi-Zhong Jing

    2013-07-01

    Full Text Available Interleukin (IL-10 inhibits the functions of antigen-presenting cells (APCs, including dendritic cells (DCs, however, the precise mechanism of action of IL-10 has not been fully elucidated. In this work, the effects of IL-10 on classical swine fever virus (CSFV C-strain-infected mouse bone marrow-derived immature DCs (BM-imDCs were studied. Additional IL-10 suppressed the maturation of the infected BM-imDCs by down-regulating the expression levels of the surface molecules CD80, CD86 and major histocompatibility complex (MHC classII, while the autocrine IL-10 had no significant effect on the maturation status of the cells. Both additional and autocrine IL-10 markedly inhibited the secretion production of IL-12P40 derived from the BM-imDCs infected with the C-strain, and reduced the capacity of DCs to promote allogeneic naive T cell proliferation. These results showed that IL-10 may play an important role in the DCs-dependent immune response induced by CSFV C-strain.

  14. Genetic Diversity and Positive Selection Analysis of Classical Swine Fever Virus Envelope Protein Gene E2 in East China under C-Strain Vaccination.

    Science.gov (United States)

    Hu, Dongfang; Lv, Lin; Gu, Jinyuan; Chen, Tongyu; Xiao, Yihong; Liu, Sidang

    2016-01-01

    Classical swine fever virus (CSFV) causes an economically important and highly contagious disease of pigs worldwide. C-strain vaccination is one of the most effective ways to contain this disease. Since 2014, sporadic CSF outbreaks have been occurring in some C-strain vaccinated provinces of China. To decipher the disease etiology, 25 CSFV E2 genes from 169 clinical samples were cloned and sequenced. Phylogenetic analyses revealed that all 25 isolates belonged to subgenotype 2.1. Twenty-three of the 25 isolates were clustered in a newly defined subgenotype, 2.1d, and shared some consistent molecular characteristics. To determine whether the complete E2 gene was under positive selection pressure, we used a site-by-site analysis to identify specific codons that underwent evolutionary selection, and seven positively selected codons were found. Three positively selected sites (amino acids 17, 34, and 72) were identified in antigenicity-relevant domains B/C of the amino-terminal half of the E2 protein. In addition, another positively selected site (amino acid 200) exhibited a polarity change from hydrophilic to hydrophobic, which may change the antigenicity and virulence of CSFV. The results indicate that the circulating CSFV strains in Shandong province were mostly clustered in subgenotype 2.1d. Moreover, the identification of these positively selected sites could help to reveal molecular determinants of virulence or pathogenesis, and to clarify the driving force of CSFV evolution in East China. PMID:26903966

  15. Studying the Antimicrobial and Antiviral Effects of Electrochemically Activated Nacl Solutions of Anolyte and Catholyte on a Strain of E. Coli DH5 and Classical Swine Fever (CSF) Virus

    OpenAIRE

    Georgi Gluhchev; Ignat Ignatov; Stoil Karadzhov; Georgi Miloshev; Nikolay Ivanov; Oleg Mosin

    2015-01-01

    This paper outlines the results on the antiviral and antimicrobial action of electrochemically activated NaCl solutions (anolyte/catholyte), produced in the anode and cathode chamber of the electrolitic cell, on classical swine fever (CSF) virus and a stain of E. coli DH5. It was found that the anolyte did not affect the growth of the cell culture PK-15; the viral growth during the infection of a cell monolayer with a cell culture virus was affected in the greatest degree by the anolyte in 1:...

  16. Variant (Swine Origin) Influenza Viruses in Humans

    Science.gov (United States)

    ... Past Newsletters Variant (Swine Origin) Influenza Viruses in Humans Language: English Español Recommend on Facebook Tweet ... Page Background Reporting Additional Information Key Facts about Human Infections with Variant Viruses (Swine Origin Influenza Viruses ...

  17. Factors associated with the introduction of classical swine fever virus into pig herds in the central area of the 1997/98 epidemic in The Netherlands.

    Science.gov (United States)

    Elbers, A R; Stegeman, J A; de Jong, M C

    2001-09-29

    A matched case-control study of 135 infected and 99 uninfected pig herds from the central area of the 1997 to 1998 epidemic of classical swine fever (CSF) in The Netherlands was undertaken to identify factors associated with the introduction of the virus. The herds were matched on the basis of herd type and the shortest geographical distance between pairs of herds. Data on management, hygienic measures, experiences during the depopulation of an infected nearest neighbour, and the frequency of contact with professionals and other agencies were collected by means of a questionnaire taken by personal interview. There were no significant differences between the infected and uninfected herds in the median total number of contacts per year with professionals and other agencies either with or without contact with the pigs. On the basis of a multivariable analysis, five variables were found to be significantly associated with an increased risk of infection: (1) the presence of commercial poultry on the premises; (2) visitors entering the pig units without wearing an overcoat or overalls and boots supplied by the farm; (3) the driver of the lorry transporting pigs for the Pig Welfare Disposal Scheme (PWDS) using his own boots instead of boots supplied by the farm; (4) herds of moderate size (500 to 1,000 animals) and very large herds (>7,000 animals) were at greater risk than small herds (wind on to the premises. Two variables were significantly associated with a decreased risk of CSFV-infection: (1) more than 30 years of experience in pig farming; and (2) additional cleaning of the lorries used to transport pigs for the PWDS before they were allowed on to the premises. In the opinion of the cooperating farmers, airborne transmission of the virus and its transmission during the depopulation of an infected neighbour were among the most important routes of infection. PMID:11601514

  18. 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.

  19. Risk factors for farm-level African swine fever infection in major pig-producing areas in Nigeria, 1997-2011.

    Science.gov (United States)

    Fasina, F O; Agbaje, M; Ajani, F L; Talabi, O A; Lazarus, D D; Gallardo, C; Thompson, P N; Bastos, A D S

    2012-11-01

    African swine fever (ASF) is an economically devastating disease for the pig industry, especially in Africa. Identifying what supports infection on pig farms in this region remains the key component in developing a risk-based approach to understanding the epidemiology of ASF and controlling the disease. Nigeria was used for this matched case-control study, because there is perpetual infection in some areas, while contiguous areas are intermittently infected. Risk factors and biosecurity practices in pig farms were evaluated in association with ASF infection. Subsets of farms located in high-density pig population areas and high-risk areas for ASF infection were randomly selected for analysis. Most plausible risk factor variables from the univariable analysis included in the multivariable analysis include: owner of farm had regular contact with infected farms and other farmers, untested pigs were routinely purchased into the farm in the course of outbreaks, there was an infected neighbourhood, other livestock were kept alongside pigs, there was a presence of an abattoir/slaughter slab in pig communities, wild birds had free access to pig pens, tools and implements were routinely shared by pig farmers, there was free access to feed stores by rats, and feed was purchased from a commercial source. Only the presence of an abattoir in a pig farming community (OR=8.20; CI(95%)=2.73, 24.63; Ppig farm in the neighbourhood (OR=3.26; CI(95%)=1.20, 8.83; P=0.02) were significant. There was a marginally significant negative association (protective) between risk of ASF infection and sharing farm tools and equipment (OR=0.35; CI(95%)=0.12, 1.01; P=0.05). Of the 28 biosecurity measures evaluated, food and water control (OR=0.14; CI(95%)=0.04, 0.46; Ppigs (OR=0.14; CI(95%)=0.04, 0.53; P=0.004) and washing and disinfection of farm equipment and tools (OR=0.27; CI(95%)=0.10, 0.78; P=0.02) were negatively associated (protective) with ASF infection. Consultation and visits by

  20. Swine Influenza/Variant Influenza Viruses

    Science.gov (United States)

    ... Documents (General) Workers Employed at Commercial Swine Farms Influenza Types Seasonal Avian Swine Variant Pandemic Other Get ... this? Submit Button Past Newsletters Information on Swine Influenza/Variant Influenza Viruses Language: English Español Recommend ...

  1. Complete genome sequence of a classical Swine Fever virus isolate belonging to a new subgenotype, 2.1c, from guangxi province, china.

    Science.gov (United States)

    Shao, Weixing; Huang, Yaohua; Liu, Shuang; Wu, Faxing; Zhang, Zhi; Dong, Yaqin; Li, Xiaocheng

    2015-01-01

    The complete genome sequence of a field isolate of classical swine fever strain (CSFV), GXF29/2013, was determined in this study. This strain was originally isolated from infected pigs in Guangxi Province, China. The most significant difference in the amino acid sequence of the polyprotein from subgenotypes 2.1a and 2.1b is an SPA→APV amino acid substitution at positions 88 and 90 in the E2 protein. PMID:26044412

  2. The N-terminal domain of Npro of classical swine fever virus determines its stability and regulates type I IFN production.

    Science.gov (United States)

    Mine, Junki; Tamura, Tomokazu; Mitsuhashi, Kazuya; Okamatsu, Masatoshi; Parchariyanon, Sujira; Pinyochon, Wasana; Ruggli, Nicolas; Tratschin, Jon-Duri; Kida, Hiroshi; Sakoda, Yoshihiro

    2015-07-01

    The viral protein Npro is unique to the genus Pestivirus within the family Flaviviridae. After autocatalytic cleavage from the nascent polyprotein, Npro suppresses type I IFN (IFN-α/β) induction by mediating proteasomal degradation of IFN regulatory factor 3 (IRF-3). Previous studies found that the Npro-mediated IRF-3 degradation was dependent of a TRASH domain in the C-terminal half of Npro coordinating zinc by means of the amino acid residues C112, C134, D136 and C138. Interestingly, four classical swine fever virus (CSFV) isolates obtained from diseased pigs in Thailand in 1993 and 1998 did not suppress IFN-α/β induction despite the presence of an intact TRASH domain. Through systematic analyses, it was found that an amino acid mutation at position 40 or mutations at positions 17 and 61 in the N-terminal half of Npro of these four isolates were related to the lack of IRF-3-degrading activity. Restoring a histidine at position 40 or both a proline at position 17 and a lysine at position 61 based on the sequence of a functional Npro contributed to higher stability of the reconstructed Npro compared with the Npro from the Thai isolate. This led to enhanced interaction of Npro with IRF-3 along with its degradation by the proteasome. The results of the present study revealed that amino acid residues in the N-terminal domain of Npro are involved in the stability of Npro, in interaction of Npro with IRF-3 and subsequent degradation of IRF-3, leading to downregulation of IFN-α/β production. PMID:25809915

  3. 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), s. 26637. ISSN 2045-2322 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: 5.578, year: 2014

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

    International Nuclear Information System (INIS)

    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)

  5. Pathology and molecular diagnosis of classical swine fever in Mizoram

    Directory of Open Access Journals (Sweden)

    David Malswamkima

    2015-01-01

    Full Text Available Aim: Clinical histopathological and molecular diagnosis of classical swine fever disease in pigs of Mizoram. Materials and Methods: Totally, 31 clinically suspected pigs from 6 districts of Mizoram were examined, and clinical symptoms were recorded. Detailed post mortem examination of all the 31 dead animals was conducted, and gross changes were recorded. Tissue samples were collected for histopathological examination and molecular diagnosis. The collected tissues (tonsil, lymph nodes, spleen were also processed for RNA extraction. Reverse transcription polymerase chain reaction (RT-PCR was performed to detect the specific gene fragments of classical swine fever virus (CSFV. Results: Clinical examination of all the 31 suspected pigs revealed typical clinical signs of CSF. All the animals also showed typical gross and microscopic lesions of CSF. RT-PCR on tissue samples amplified the 421bp, 449bp and 735bp region of 5´NCR, non-structural protein 5B and Erns gene regions of CSFV, respectively. Nested PCR for internal region of E2 gene also amplified the expected product of 271bp using PCR product of whole E2 region as template DNA. Conclusion: CSF is highly endemic disease in Mizoram. The viral strains circulating in this region are highly virulent. The disease can be diagnosed specifically using RT-PCR.

  6. The Culture Characteristics of Classical swine fever virus C-strain(Derived from Spleen) in SK6 Cell and Its Detection%猪瘟病毒C株兔脾毒在SK6细胞中的增殖培养及其鉴定

    Institute of Scientific and Technical Information of China (English)

    张淼涛; 冯霞; 刘湘涛; 张彦明; 谢庆阁

    2004-01-01

    Enzyme-linked immunosorbent assay(ELISA), direct florescent antibody staining, and RT-PCT were used to detect growth characteristics of Cassical swine fever virus C-strain (Derived from Spleen) in SK6 cell. The results indicated than C-strain (Derived from Spleen) can grow in SK6 cell at a lower level. Direct florescent antibody staining method was not suitable for the detection of attenuated lapinized C-strain. The study provided a primary guide for the detection of attenuated classical swine fever virus. It also supplies an elementary foundation for the study of its growth characteristic in SK6.

  7. 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...

  8. 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, the...

  9. 猪瘟病毒分子生物学与致病机制研究进展%Research advance in molecular biology and pathogenetic mechanism for classical swine fever virus

    Institute of Scientific and Technical Information of China (English)

    南文金; 胡鸿惠; 彭国良; 娄高明

    2011-01-01

    猪瘟是由猪瘟病毒感染导致的高度接触性传染病,家猪和野猪对该病原易感.该病主要特征是高热、微血管变性而引起实质器官出血、坏死,是世界上危害最严重猪病之一,给养猪业带来重大损失.综述了猪瘟病毒基因组、蛋白质功能以及致病机理的最新研究进展,为相关研究人员参考.%Classical swine fever (CSF) is a highly contagious disease of domestic and wild pigs. The causative agent of this disease is classical swine fever virus (CSFV), the disease of pig characterized by high fever, microvascular denaturalization hemorrhages and necrosis of parenchymatous argans. It is considered to be one of the most devastating diseases and causes significant economic loss for the pig industry throughout the word. The paper introduces the research progresses on genome, function of protein and pathogenesis of CFSV.

  10. Influenza A virus pathogenesis and vaccination in swine

    Science.gov (United States)

    Swine influenza is an acute respiratory disease of pigs that is characterized by fever followed by lethargy, anorexia, and serous nasal discharge. The disease progresses rapidly and may be complicated when associated with other respiratory pathogens. Influenza A virus (IAV) is one of the most preval...

  11. Identifiction and Detection of Classical Swine Fever Virus in A Pig Farm of Xinxiang%新乡市某猪场猪瘟病毒的鉴别检测

    Institute of Scientific and Technical Information of China (English)

    孔令芸; 陈玲丽; 李冲; 孙相和; 李鹏; 王选年; 银梅

    2015-01-01

    新乡市某猪场发生疑似猪瘟病例,为了鉴别其为疫苗毒还是野毒,采用细胞免疫化学方法和RT-PCR,并对其NS5B基因进行序列测定,序列比对并构建进化树,结果表明,猪只为猪瘟野毒感染,且分离的猪瘟病毒与石门(Shimen)株在基因序列上未发生大的变异。%The suspicious cases of classical swine fever occurred in a pig farm of Xinxiang.The virus was i-dentified by cell immunochemistry method and RT-PCR.The results of the sequence alignment and phylo-genetic tree of NS5B gene showed that the pigs were infected with classical swine fever virus field strain, and the gene sequence variation of this isolate was not obvious.

  12. Research Progress on Differential Methods of Wild-type and Vaccine Virus of Classical Swine Fever%猪瘟野毒与疫苗弱毒鉴别方法的研究进展

    Institute of Scientific and Technical Information of China (English)

    杭柏林; 胡建和; 王青; 史杰; 李杰; 朱王飞

    2011-01-01

    概述了当前鉴别猪瘟强弱毒的几种方法,即免疫学方法(胶体金免疫层析技术、单克隆抗体法和单抗-酶联免疫吸附试验)、核酸检测方法(RT-PCR技术、RT-PCR与其他方法的结合)和动物试验方法.同时提出了鉴别猪瘟强弱毒方法的发展方向.%This paper mainly summarizes differential methods of wild-type and vaccine virus of classical swine fever, which are immunology methods(GICA, McAb and McAb-ELISA), nucleic acid detection methods(RT-PCR and combination approach of RT-PCR with other methods) and animal test method.And the potential development directions of differential methods of wild-type and vaccine virus of classical swine fever are also proposed in this paper.

  13. Next-generation sequencing of southern African Crimean-Congo haemorrhagic fever virus isolates reveals a high frequency of M segment reassortment.

    Science.gov (United States)

    Goedhals, D; Bester, P A; Paweska, J T; Swanepoel, R; Burt, F J

    2014-09-01

    Crimean Congo haemorrhagic fever virus (CCHFV) is a bunyavirus with a single-stranded RNA genome consisting of three segments (S, M, L), coding for the nucleocapsid protein, envelope glycoproteins and RNA polymerase, respectively. To date only five complete genome sequences are available from southern African isolates. Complete genome sequences were generated for 10 southern African CCHFV isolates using next-generation sequencing techniques. The maximum-likelihood method was used to generate tree topologies for 15 southern African plus 26 geographically distinct complete sequences from GenBank. M segment reassortment was identified in 10/15 southern African isolates by incongruencies in grouping compared to the S and L segments. These reassortant M segments cluster with isolates from Asia/Middle East, while the S and L segments cluster with strains from South/West Africa. The CCHFV M segment shows a high level of genetic diversity, while the S and L segments appear to co-evolve. The reason for the high frequency of M segment reassortment is not known. It has previously been suggested that M segment reassortment results in a virus with high fitness but a clear role in increased pathogenicity has yet to be shown. PMID:24786748

  14. Mayaro Fever Virus, Brazilian Amazon

    OpenAIRE

    Azevedo, Raimunda S. S.; Silva, Eliana V. P.; Carvalho, Valéria L.; Rodrigues, Sueli G.; Neto, Joaquim P. Nunes; Monteiro, Hamilton A. de O.; Peixoto, Victor S.; Chiang, Jannifer O.; Nunes, Márcio R. T.; Vasconcelos, Pedro F.C.

    2009-01-01

    In February 2008, a Mayaro fever virus (MAYV) outbreak occurred in a settlement in Santa Barbara municipality, northern Brazil. Patients had rash, fever, and severe arthralgia lasting up to 7 days. Immunoglobulin M against MAYV was detected by ELISA in 36 persons; 3 MAYV isolates sequenced were characterized as genotype D.

  15. 竞争性ELISA检测猪瘟病毒抗原%A competitive ELISA for detection of viral antigen of classical swine fever virus

    Institute of Scientific and Technical Information of China (English)

    张富强; 李志华; 张念祖

    2005-01-01

    猪瘟(Classical swine fever,CSF)是由猪瘟病毒(Classical swine fever virus,CSFV)引起,主要侵袭家猪及野猪,引起高发病率、高死亡率的烈性传染病。由于其危害严重、流行分布广泛,成为国内外分子病毒学及兽医防疫研究的热点之一。CSFV属于黄病毒科(Flaviviridae)瘟病毒属(Pestvirus)成员,与同属的牛病毒性腹泻病毒(Bovineviral diarrhea virus,BVDV)、羊边界病病毒(Borderdiseasevirus,BDV)、长颈鹿瘟病毒(Giraffepestvirus),在病毒结构、抗原性和遗传特性等方面密切相关。

  16. Comparison of Three Detection Methods for Classical Swine Fever Virus%猪瘟病毒3种检测方法的比较

    Institute of Scientific and Technical Information of China (English)

    张艳英; 高桂生; 高光平; 史秋梅; 张贵贤; 田和杰; 李秋艳

    2013-01-01

    This paper investigated the advantages and disadvantages of three methods to detect classical swine fever virus (CSFV). We used three kinds of methods, including reverse transcription-multiplex nested polymerase chain reaction(RT-nPCR), fluorescence antibody method and colloidal gold immunochromatographic assay (CGIA), to detect 30 CSFV samples. The results showed that 11 samples of detected 30 samples were positive by RT-nPCR,13 samples were positive by fluorescence antibody method, 8 samples were positive by CGIA, and 8 samples were positive and 17 samples were negative by the three methods. Although fluorescence antibody method saved time, it needed a seasoned staff to judge results. What's more, there were many false positive results arising by the method, and its specificity was rather poor. Gold dipstick method's biggest advantage was simple and easy to operate,and it was also appropriate for primary level,while the disadvantage was that it had a low sensibility. RT-nPCR's advantage was that it had a high-speed and sensitive operation, but it needed certain equipment and mature technology tests. In addition to this, it could differentiate testing samples whether they were vaccine strain or wild strain, and this was the point which other two methods couldn't match.%本研究旨在比较3种检测猪瘟病毒方法的优缺点.应用反转录一复合套式聚合酶链式反应(RT-nPCR)、荧光抗体法、胶体金免疫层析试纸条3种方法,分别对30份疑似猪瘟病料中的猪瘟病毒进行检测.试验结果显示,RT-nPCR方法检出阳性样品数为11份,荧光抗体法为13份,胶体金免疫层析试纸条为8份;3种方法检测全为阳性8份,全为阴性17份.试验结果表明,荧光抗体检测法所需时间较短,但需要经验比较丰富人员来判定结果,且存在假阳性结果,敏感性比较差;胶体金免疫层析试纸条诊断方法最大的优点就是简便快速,且适合基层的应用,该方法的不足之处就

  17. 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

    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......-PCR protocols and a standardized protocol commonly used by the Friedrich-Loeffler-Institute (FLI) on a panel of well-characterized samples. In general, all participants produced results within the acceptable range. The FLI assay, several in-house assays, and the commercial kits had high analytical sensitivity...... 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...

  18. 猪瘟病毒非结构蛋白功能的研究进展%Research Progress on Funtion of Non-structural Proteins of Classical Swine Fever Virus

    Institute of Scientific and Technical Information of China (English)

    陈果亮; 余兴龙

    2013-01-01

    近年来,人们对猪瘟病毒(classical swine fever virus,CSFV)的结构蛋白研究比较透彻,而对非结构蛋白功能的研究相对较少.非结构蛋白对病毒的复制、致病性及对宿主细胞功能的调节均发挥重要作用,这些研究成果对于揭示CSFV的致病机理和新型疫苗的开发具有十分重要的意义.作者全面综述了CSFV非结构蛋白的生物学功能,以期为研究者提供参考.

  19. Research progress on classical swine fever%猪瘟研究新进展

    Institute of Scientific and Technical Information of China (English)

    卫广森

    2004-01-01

    猪瘟(Hog cholera or Classical Swine fever,CSF)是由猪瘟病毒(Hog cholera virus or Classical Swine fever Virus,CSFV)引起猪的一种高度接触性传染病。其流行广泛,发病率高,死亡率高。1984年世界动物卫生组织(OIE)将其列为A类传染病,我国也将此病列为一类动物疫病。

  20. The clasical swine fever vaccine - Pestivac M® dosage in wild boar’s baits

    Directory of Open Access Journals (Sweden)

    Stirbu, C.,

    2008-06-01

    Full Text Available The work presents the technical dates about vaccine baits and the results of domestic and feral pigs’ immunization against classical swine fever using these vaccine baits. The new vaccine contains modified swine fever virus grown on tissue culture encapsulated in blisters, which are incorporated into cereal-based and attractive flavors matrix measuring 4 x 4 x 1.5 cm. The new vaccine administered to domestic and feral pigs was well-accepted. Thirty days after administration more than 75% of the vaccinated feral pigs and 100% of the vaccinated domestic pigs showed good antibody levels. Further more 80% of the vaccinated domestic pigs were protected after challenged with virulent CFS virus 30 days post vaccination. The vaccine can be administered any time during the year.

  1. Prevalence of classical swine fever in Karnataka, India

    Directory of Open Access Journals (Sweden)

    Prakash Choori

    2015-04-01

    Full Text Available Aim: The present study was conducted to know the current scenario of classical swine fever (CSF in Bengaluru Urban, Bengaluru Rural, Chikkaballapur, Madikeri, Mandya, Bagalkot, Gadag, Yadgir, Koppal, and Bidar districts of Karnataka with the using of both antigen and antibody ELISA. Materials and Methods: We collected 218 sera and 121 blood samples from pigs from 10 different districts of Karnataka. Screening of sera for CSF IgG antibody and whole blood for CSF virus antigen were carried out using the CSF virus (CSFV antibody and antigen ELISA kits, respectively. Results: The mean seroprevalence was 41% (89/218 and prevalence of CSFV antigen in blood samples was 32% (39/121 for the 10 districts of Karnataka. Seroprevalence of 61%, 29%, 20%, and 21%; and antigen prevalence of 40%, 50%, 13%, and 12% were recorded for Bangalore, Mysore, Belgaum, and Gulbarga divisions of Karnataka, respectively. Conclusions: The study revealed an alarmingly high prevalence of CSF, both for the antigen (32% and antibody (41% in Karnataka. Southern Karnataka has the highest seroprevalence (61% in Bangalore and 29% in Mysore divisions, which confirms the endemicity of the disease in that region. This could be attributed to the intensive pig farming practices in the region as compared to Northern Karnataka (Seroprevalence of 20% in Belgaum and 21% in Gulbarga divisions, where the commercial pig farming is still in infantile stages.

  2. 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.

  3. Studying the Antimicrobial and Antiviral Effects of Electrochemically Activated Nacl Solutions of Anolyte and Catholyte on a Strain of E. Coli DH5 and Classical Swine Fever (CSF Virus

    Directory of Open Access Journals (Sweden)

    Georgi Gluhchev

    2015-09-01

    Full Text Available This paper outlines the results on the antiviral and antimicrobial action of electrochemically activated NaCl solutions (anolyte/catholyte, produced in the anode and cathode chamber of the electrolitic cell, on classical swine fever (CSF virus and a stain of E. coli DH5. It was found that the anolyte did not affect the growth of the cell culture PK-15; the viral growth during the infection of a cell monolayer with a cell culture virus was affected in the greatest degree by the anolyte in 1:1 dilution and less in other dilutions; whereas the viral growth at the infection of a cell suspension with the CSF virus was affected by the anolyte in dilution 1:1 in the greatest degree, and less by other dilutions; viral growth at the infection with a virus in suspension of the cell monolayer was affected by the anolyte in all dilutions. Unexpectedly, the stronger biocidal effect of the catholyte was observed when a strain of E. coli DH5 was treated by the anolyte and catholyte, respectively. In order to provide additional data about the antiviral activity of the electrochemically activated water and the distribution of H2O molecules according to the energies of hydrogen bonds, the non-equilibrium energy spectrum (NES and differential non-equilibrium energy spectrum (DNES of the anolyte and catholyte were measured.

  4. Lassa fever in West African sub-region: an overview

    Directory of Open Access Journals (Sweden)

    O. Ogbu

    2007-01-01

    Full Text Available Lassa fever is an acute viral zoonotic illness caused by Lassa virus, an arenavirus known to beresponsible for a severe haemorrhagic fever characterised by fever, muscle aches, sore throat, nausea,vomiting and, chest and abdominal pain. The virus exhibits persistent, asymptomatic infection withprofuse urinary virus excretion in the ubiquitous rodent vector, Mastomys natalensis. Lassa fever isendemic in West Africa and has been reported from Sierra Leone, Guinea, Liberia, and Nigeria. Somestudies indicate that 300,000 to 500,000 cases of Lassa fever and 5000 deaths occur yearly across WestAfrica. Studies reported in English, that investigated Lassa fever with reference to West Africa wereidentified using the Medline Entrez-PubMed search and were used for this review. The scarcity ofresources available for health care delivery system and the political instability that characterise theWest African countries would continue to impede efforts for the control of Lassa fever in the sub-region.There is need for adequate training of health care workers regarding diagnostics, intensive care ofpatients under isolation, contact tracing, adequate precautionary measures in handling infectiouslaboratory specimens, control of the vector as well as care and disposal of infectious waste.

  5. Lassa fever in West African sub-region: an overview.

    Science.gov (United States)

    Ogbu, O; Ajuluchukwu, E; Uneke, C J

    2007-03-01

    Lassa fever is an acute viral zoonotic illness caused by Lassa virus, an arenavirus known to be responsible for a severe haemorrhagic fever characterised by fever, muscle aches, sore throat, nausea, vomiting and, chest and abdominal pain. The virus exhibits persistent, asymptomatic infection with profuse urinary virus excretion in the ubiquitous rodent vector, Mastomys natalensis. Lassa fever is endemic in West Africa and has been reported from Sierra Leone, Guinea, Liberia, and Nigeria. Some studies indicate that 300,000 to 500,000 cases of Lassa fever and 5000 deaths occur yearly across West Africa. Studies reported in English, that investigated Lassa fever with reference to West Africa were identified using the Medline Entrez-PubMed search and were used for this review. The scarcity of resources available for health care delivery system and the political instability that characterise the West African countries would continue to impede efforts for the control of Lassa fever in the sub-region. There is need for adequate training of health care workers regarding diagnostics, intensive care of patients under isolation, contact tracing, adequate precautionary measures in handling infectious laboratory specimens, control of the vector as well as care and disposal of infectious waste. PMID:17378212

  6. Comparative studies on the pathogenicity and tissue distribution of three virulence variants of classical swine fever virus, two field isolates and one vaccine strain, with special regard to immunohistochemical investigations

    Directory of Open Access Journals (Sweden)

    Vanderhallen Hans

    2008-09-01

    Full Text Available Abstract Background The aim of this study was to compare the tissue distribution and pathogenicity of three virulence variants of classical swine fever virus (CSFV and to investigate the applicability of various conventional diagnostic procedures. Methods 64 pigs were divided into three groups and infected with the highly virulent isolate ISS/60, the moderately virulent isolate Wingene'93 and the live attenuated vaccine strain Riems, respectively. Clinical signs, gross and histopathological changes were compared in relation to time elapsed post infection. Virus spread in various organs was followed by virus isolation, by immunohistochemistry, applying monoclonal antibodies in a two-step method and by in situ hybridisation using a digoxigenin-labelled riboprobe. Results The tissue distribution data are discussed in details, analyzing the results of the various diagnostic approaches. The comparative studies revealed remarkable differences in the onset of clinical signs as well as in the development of the macro- and microscopical changes, and in the tissue distribution of CSFV in the three experimental groups. Conclusion The present study demonstrates that in the case of highly and moderately virulent virus variants the virulence does not affect the pattern of the viral spread, however, it influences the outcome, the duration and the intensity of the disease. Immunohistochemistry has the advantage to allow the rapid detection and localisation of the virus, especially in cases of early infection, when clinical signs are still absent. Compared to virus isolation, the advantage of this method is that no cell culture facilities are required. Thus, immunohistochemistry provides simple and sensitive tools for the prompt detection of newly emerging variants of CSFV, including the viruses of very mild virulence.

  7. Epidemic Status of Swine Influenza Virus in China

    OpenAIRE

    Kong, Weili; Ye, Jiahui; Guan, Shangsong; Liu, Jinhua; Pu, Juan

    2013-01-01

    As one of the most significant swine diseases, in recent years, swine influenza (SI) has had an immense impact on public health and has raised extensive public concerns in China. Swine are predisposed to both avian and human influenza virus infections, between that and/or swine influenza viruses, genetic reassortment could occur. This analysis aims at introducing the history of swine influenza virus, the serological epidemiology of swine influenza virus infection, the clinical details of swin...

  8. Sandfly Fever Sicilian Virus, Algeria

    OpenAIRE

    Izri, Arezki; Temmam, Sarah; Moureau, Grégory; Hamrioui, Boussad; de Lamballerie, Xavier; Charrel, Rémi N.

    2008-01-01

    To determine whether sandfly fever Sicilian virus (SFSV) is present in Algeria, we tested sandflies for phlebovirus RNA. A sequence closely related to that of SFSV was detected in a Phlebotomus ariasi sandfly. Of 60 human serum samples, 3 contained immunoglobulin G against SFSV. These data suggest SFSV is present in Algeria.

  9. Challenge of pigs with classical swine fever viruses after C-strain vaccination reveals remarkably rapid protection and insights into early immunity.

    Directory of Open Access Journals (Sweden)

    Simon P Graham

    Full Text Available Pre-emptive culling is becoming increasingly questioned as a means of controlling animal diseases, including classical swine fever (CSF. This has prompted discussions on the use of emergency vaccination to control future CSF outbreaks in domestic pigs. Despite a long history of safe use in endemic areas, there is a paucity of data on aspects important to emergency strategies, such as how rapidly CSFV vaccines would protect against transmission, and if this protection is equivalent for all viral genotypes, including highly divergent genotype 3 strains. To evaluate these questions, pigs were vaccinated with the Riemser® C-strain vaccine at 1, 3 and 5 days prior to challenge with genotype 2.1 and 3.3 challenge strains. The vaccine provided equivalent protection against clinical disease caused by for the two challenge strains and, as expected, protection was complete at 5 days post-vaccination. Substantial protection was achieved after 3 days, which was sufficient to prevent transmission of the 3.3 strain to animals in direct contact. Even by one day post-vaccination approximately half the animals were partially protected, and were able to control the infection, indicating that a reduction of the infectious potential is achieved very rapidly after vaccination. There was a close temporal correlation between T cell IFN-γ responses and protection. Interestingly, compared to responses of animals challenged 5 days after vaccination, challenge of animals 3 or 1 days post-vaccination resulted in impaired vaccine-induced T cell responses. This, together with the failure to detect a T cell IFN-γ response in unprotected and unvaccinated animals, indicates that virulent CSFV can inhibit the potent antiviral host defences primed by C-strain in the early period post vaccination.

  10. Chinese border disease virus strain JSLS12-01 infects piglets and down-regulates the antibody responses of classical swine fever virus C strain vaccination.

    Science.gov (United States)

    Mao, Li; Li, Wenliang; Liu, Xia; Hao, Fei; Yang, Leilei; Deng, Jiawu; Zhang, Wenwen; Wei, Jianzhong; Jiang, Jieyuan

    2015-07-31

    During 2012 and 2013, several border disease virus (BDV) strains were identified from Chinese goat and sheep herds. At the same time, pigs from the same areas were found to be seropositive to BDV by ELISA, without showing clinical signs (unpublished data). To examine the susceptibility of pigs to the Chinese BDV strains, BDV isolate JSLS12-01, isolated from naturally infected sheep, was used to infect pigs. Antibody responses, viremia, clinical signs and pathological changes of the infected animals were examined. It confirmed that the current BDV strain could infect the domestic pigs, the animals showed viremia during 4 to 14 days post infection (dpi) and sero-conversion from 14dpi; no clinical and pathological changes were observed. In addition, CSFV maternal antibody did not influence BDV infection. Subsequently, pigs were infected with the BDV isolate and vaccinated with Hog cholera lapinized virus (HCLV) 21 days later to determine the effect of BDV infection on antibody induction of CSFV vaccination. The specific CSFV antibody and neutralizing antibody titers of the BDV infected group remained negative after the primary vaccination. Even after the boost vaccination, they were still significantly lower than those of the uninfected groups (p<0.05). These results indicated that BDV infection could down-regulate the antibody responses of CSFV C-strain vaccination. It should be paid attention that BDV prevalence in pig herds and in live vaccines might hamper the vaccination of CSF. PMID:26117151

  11. Antigenic analysis of classical swine fever virus E2 glycoprotein using pig antibodies identifies residues contributing to antigenic variation of the vaccine C-strain and group 2 strains circulating in China

    Directory of Open Access Journals (Sweden)

    Peng Jinrong

    2010-12-01

    Full Text Available Abstract Background Glycoprotein E2, the immunodominant protein of classical swine fever virus (CSFV, can induce neutralizing antibodies and confer protective immunity in pigs. Our previous phylogenetic analysis showed that subgroup 2.1 viruses branched away from subgroup 1.1, the vaccine C-strain lineage, and became dominant in China. The E2 glycoproteins of CSFV C-strain and recent subgroup 2.1 field isolates are genetically different. However, it has not been clearly demonstrated how this diversity affects antigenicity of the protein. Results Antigenic variation of glycoprotein E2 was observed not only between CSFV vaccine C-strain and subgroup 2.1 strains, but also among strains of the same subgroup 2.1 as determined by ELISA-based binding assay using pig antisera to the C-strain and a representative subgroup 2.1 strain QZ-07 currently circulating in China. Antigenic incompatibility of E2 proteins markedly reduced neutralization efficiency against heterologous strains. Single amino acid substitutions of D705N, L709P, G713E, N723S, and S779A on C-strain recombinant E2 (rE2 proteins significantly increased heterologous binding to anti-QZ-07 serum, suggesting that these residues may be responsible for the antigenic variation between the C-strain and subgroup 2.1 strains. Notably, a G713E substitution caused the most dramatic enhancement of binding of the variant C-strain rE2 protein to anti-QZ-07 serum. Multiple sequence alignment revealed that the glutamic acid residue at this position is conserved within group 2 strains, while the glycine residue is invariant among the vaccine strains, highlighting the role of the residue at this position as a major determinant of antigenic variation of E2. A variant Simpson's index analysis showed that both codons and amino acids of the residues contributing to antigenic variation have undergone similar diversification. Conclusions These results demonstrate that CSFV vaccine C-strain and group 2 strains

  12. Radiation Inactivation of Viruses in Infected Products

    International Nuclear Information System (INIS)

    Full text: The effects of gamma radiation on foot-and-mouth disease virus in vitro and in situ have been studied. The data so far obtained show that a dose of 2 Mrad is required to inactivate virus in infected animal carcasses. But the dose may adversely affect the organoleptic quality of the meat. Experiments in vitro and in situ are necessary to study the effects of ionizing radiation on other viruses, such as rinderpest, swine fever and African swine fever-viruses, associated with animal products. Radiation may offer a possible means of eliminating the virus titre in many animal products and solve consequent quarantine problems. (author)

  13. Economic Analysis of Classical Swine Fever Surveillance in the Netherlands.

    Science.gov (United States)

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

    2016-06-01

    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 analysis is required to compare the benefits of improved surveillance with the costs of implementing a more intensive system. This study presents a comprehensive economic analysis of CSF surveillance in the Netherlands, taking into account the specialized structure of Dutch pig production, differences in virulence of CSF strains and a complete list of possible surveillance activities. The starting point of the analysis is the current Dutch surveillance system (i.e. the default surveillance-setup scenario), including the surveillance activities 'daily clinical observation by the farmer', 'veterinarian inspection after a call', 'routine veterinarian inspection', 'pathology in AHS', 'PCR on tonsil in AHS', 'PCR on grouped animals in CVI' and 'confirmatory PCR by NVWA'. Alternative surveillance-setup scenarios were proposed by adding 'routine serology in slaughterhouses', 'routine serology on sow farms' and 'PCR on rendered animals'. The costs and benefits for applying the alternative surveillance-setup scenarios were evaluated by comparing the annual mitigated economic losses because of intensified CSF surveillance with the annual additional surveillance costs. The results of the cost-effectiveness analysis show that the alternative surveillance-setup scenarios with 'PCR on rendered animals' are effective for the moderately virulent CSF strain, whereas the scenarios with 'routine serology in slaughterhouses' or 'routine serology on sow farms' are effective for the low virulent strain. Moreover, the current CSF surveillance system in the Netherlands is cost-effective for both moderately virulent and low virulent CSF strains. The results of the cost-benefit analysis for the

  14. 猪瘟病毒的形态结构及侵染机理的研究%Preliminary study on the morphology and infectious mechanism of classical swine fever virus

    Institute of Scientific and Technical Information of China (English)

    聂玉春; 王镇; 周海霞; 邓宏魁; 丁明孝

    2002-01-01

    @@ 猪瘟病毒(classical swine fever virus,CSFV),属黄病毒科,瘟病毒属成员,是严重危害养猪生产的主要病原体之一.CSFV是具有囊膜的正链RNA病毒.除基因组RNA外,还有衣壳蛋白C和三种囊膜蛋白E0,E1和E2组成.一般认为病毒侵染细胞是通过囊膜蛋白与细胞表面受体相互作用形成Infecosome后进入宿主细胞.然而对CSFV感染细胞的细节当不甚明了.本项研究在观察CSFV形态结构与发生过程的基础上对其侵染细胞的机理进行了初步研究.

  15. 猪瘟病毒E2蛋白B细胞识别基序的筛选%Screening for B cell liner epitope on E2 protein of classical swine fever virus

    Institute of Scientific and Technical Information of China (English)

    王爱萍; 马丽平; 李姣; 邓瑞广; 邢广绪; 郝慧芳

    2008-01-01

    根据猪瘟病毒(classical swine fever virus,CSFV)E2蛋白的序列设计并人工合成18条重叠多肽,与载体蛋白BSA偶联后,利用抗CSFV E2蛋白单克隆抗体SWmAb8筛选该蛋白上的B细胞表位;同时用12肽噬菌体随机肽库淘选E2单抗识别多肽序列.结果显示,多肽序列VSPTTLRTEV能被单抗SWmAb8识别;含SPTxLR基序的噬菌体能被单抗SWmAb8结合,且能被病毒抗原竞争性抑制.证实SPTFxLR基序很可能是E2蛋白的线性表位之一,可诱导机体产生中和抗体.

  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. Scientific Opinion on African swine fever

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Animal Health and Welfare (AHAW

    2014-04-01

    Full Text Available The risk for endemicity of ASF in the eastern neighbouring countries of the EU and spread of ASFV to unaffected areas was updated until 31/01/2014. The assessment was based on a literature review and expert knowledge elicitation. The risk that ASF is endemic in Georgia, Armenia and the Russian Federation has increased from moderate to high, particularly due to challenges in outbreak control in the backyard production sector. The risk that ASFV will spread further into unaffected areas from these countries, mainly through movement of contaminated pork, infected pigs or contaminated vehicles, has remained high. In Ukraine and Belarus, the risk for ASF endemicity was considered moderate. Although only few outbreaks have been reported, which have been stamped out, only limited activities are ongoing to facilitate early detection of secondary spread. Further, there is a continuous risk of ASFV re-introduction from the Russian Federation, due to transboundary movements of people, pork or infected wild boar. The number of backyard farms is greatest in the west of Ukraine and westwards spread of ASFV could result in an infected area near the EU border, difficult to control. In Georgia, Armenia and the Russian Federation, the risk for endemicity of ASF in the wild boar population is considered moderate, mainly due to spill-over from the domestic pig population, whereas in Ukraine and Belarus this was considered to be low. In those areas in the Russian Federation where wild boar density is high, this risk may be higher. Intensive hunting pressure in affected wild boar populations may increase the risk for spread, possibly with severe implications across international borders. The risk for different matrices to be infected/contaminated and maintain infectious ASFV at the moment of transportation into the EU was assessed and ranged from very high for frozen meat, to very low for crops.

  18. Detection of classical swine fever virus (CSFV) in clinical samples by RT-PCR assay in clinical samples by RT-PCR assay using different pairs of primers

    International Nuclear Information System (INIS)

    The aim was to compare the efficiency of RT-PCT assays using four pairs of primers selected from different regions of the CSFV genome for the detection of CSFV in clinical samples of swine and wild boars. The four RT-PCR assays were able to detect CSFV in all 20 clinical samples which had been collected from dead swine and wild boars during the outbreaks of CSF in Slovakia in 1993 and 1994. The quality of the selected RT-PCR primers was determined as follows: gp55L/gp55U (E2), 324/326 (5'-NC), S1/S2 (NS5B) and gp54L/gp54U (NS2 genomic region). We conclude that gp55L/gp55U primers are the most suitable for direct detection of CSFV by RT-PCR in tissue homogenates of diseased animals

  19. Lassa fever in West African sub-region: an overview

    OpenAIRE

    O. Ogbu; E. Ajuluchukwu; Uneke, C.J.

    2007-01-01

    Lassa fever is an acute viral zoonotic illness caused by Lassa virus, an arenavirus known to beresponsible for a severe haemorrhagic fever characterised by fever, muscle aches, sore throat, nausea,vomiting and, chest and abdominal pain. The virus exhibits persistent, asymptomatic infection withprofuse urinary virus excretion in the ubiquitous rodent vector, Mastomys natalensis. Lassa fever isendemic in West Africa and has been reported from Sierra Leone, Guinea, Liberia, and Nigeria. Somestud...

  20. An update on safety studies on the attenuated ?RIEMSER? Schweinepestoralvakzine? for vaccination of wild boar against classical swine fever

    OpenAIRE

    Kaden, Volker; Lange, Elke; Küster, Heike; Müller, Thomas; Lange, Bodo

    2009-01-01

    Abstract The RIEMSER? Schweinepestoralvakzine is an attenuated vaccine for oral vaccination of wild boar against classical swine fever (CSF). The safety of this licensed bait vaccine which is based on the CSF virus (CSFV) strain ?C? was investigated in 8 animal species, e.g. weaner pigs (n=111), wild boar (n=11), ruminants (cattle, goats and sheep, n=11), foxes (n=5), rabbits (n=12), and mice (n=10). Animals were vaccinated either with a single vaccine dose containing at least 104....

  1. Evaluation of an Erns-based enzyme-linked immunosorbent assay to distinguish Classical swine fever virus-infected pigs from pigs vaccinated with CP7_E2alf.

    Science.gov (United States)

    Pannhorst, Katrin; Fröhlich, Andreas; Staubach, Christoph; Meyer, Denise; Blome, Sandra; Becher, Paul

    2015-07-01

    Infections with Classical swine fever virus (CSFV) are a major economic threat to pig production. To combat CSF outbreaks and to maintain trade, new marker vaccines were developed that allow differentiation of infected from vaccinated animals (DIVA principle). The chimeric pestivirus CP7_E2alf was shown to be safe and efficacious. Its DIVA strategy is based on the detection of CSFV E(rns)-specific antibodies that are only developed on infection. However, for the new marker vaccine to be considered a valuable control tool, a validated discriminatory assay is needed. One promising candidate is the already commercially available enzyme-linked immunosorbent assay, PrioCHECK CSFV E(rns) ELISA (Prionics BV, Lelystad, The Netherlands). Four laboratories of different European Union member states tested 530 serum samples and country-specific field sera from domestic pigs and wild boar. The ELISA displayed a good robustness. However, based on its reproducibility and repeatability, ranges rather than single values for diagnostic sensitivity and specificity were defined. The ELISA displayed a sensitivity of 90-98% with sera from CSFV-infected domestic pigs. A specificity of 89-96% was calculated with sera from domestic pigs vaccinated once with CP7_E2alf. The ELISA detected CSFV infections in vaccinated domestic pigs with a sensitivity of 82-94%. The sensitivity was lower with sera taken ≤21 days post-challenge indicating that the stage of CSFV infection had a considerable influence on testing. Taken together, the PrioCHECK CSFV E(rns) ELISA can be used for detection of CSFV infections in CP7_E2alf-vaccinated and nonvaccinated domestic pig populations, but should only be applied on a herd basis by testing a defined number of animals. PMID:26179095

  2. Research Progress on Molecular Biology Detection Technique of Classical Swine Fever%猪瘟的分子生物学检测技术研究进展

    Institute of Scientific and Technical Information of China (English)

    王茁; 赵福广

    2011-01-01

    Classical Swine Fever is a fatal and widely infectious disease caused by Classical Swine Fever Virus. Molecular biology plays an active role in studying the epidemiological characteristics of Classical Swine Fever, especially in laboratory diagnosis. This paper illustrates several major integrated molecular biology detection techniques of Classical Swine Fever,which aims at offering a reference for fast, accurate and high-throughput detection of Classical Swine Fever Virus.%猪瘟是由猪瘟病毒引起的高致死率的烈性传染病.针对猪瘟近年来的发病特征,分子生物学检测技术在实验室诊断中发挥了重要作用.对几种主要的猪瘟分子生物学检测技术进行了综述,为快速、准确、高通量地检测猪瘟病毒提供参考.

  3. Surveillance of classical swine fever in wild boar in South Korea from 2010-2014.

    Science.gov (United States)

    Kim, Yong Kwan; Lim, Seong-In; Kim, Jae-Jo; Cho, Yoon-Young; Song, Jae-Young; Cho, In-Soo; Hyun, Bang-Hun; Choi, Sung-Hyun; Kim, Seung-Hoe; Park, Eun-Hye; An, Dong-Jun

    2016-01-01

    Classical swine fever (CSF) is a highly contagious systemic hemorrhagic viral disease of pigs. Wild boar plays a crucial role in the epidemiology of CSF. Between 2010 and 2014, samples were collected nationwide from 6,654 wild boars hunted in South Korea. Anti-CSF antibodies were identified in 0.59% (39 of 6,654) of the wild boar samples using a virus neutralization test and were primarily detected in wild boars living close to the demilitarized zone and the area of the Taebaek Mountains surroundings. The CSF virus (subgroup 2.1b) was isolated from two wild boars captured in a nearby border area. The criteria used to define high-risk areas for targeted CSF surveillance in South Korea should be further expanded to include other regions nationwide. PMID:26178821

  4. Proteome-wide screening reveals immunodominance in the CD8 T cell response against classical swine fever virus with antigen-specificity dependent on MHC class I haplotype expression.

    Directory of Open Access Journals (Sweden)

    Giulia Franzoni

    Full Text Available Vaccination with live attenuated classical swine fever virus (CSFV vaccines induces a rapid onset of protection which has been associated with virus-specific CD8 T cell IFN-γ responses. In this study, we assessed the specificity of this response, by screening a peptide library spanning the CSFV C-strain vaccine polyprotein to identify and characterise CD8 T cell epitopes. Synthetic peptides were pooled to represent each of the 12 CSFV proteins and used to stimulate PBMC from four pigs rendered immune to CSFV by C-strain vaccination and subsequently challenged with the virulent Brescia strain. Significant IFN-γ expression by CD8 T cells, assessed by flow cytometry, was induced by peptide pools representing the core, E2, NS2, NS3 and NS5A proteins. Dissection of these antigenic peptide pools indicated that, in each instance, a single discrete antigenic peptide or pair of overlapping peptides was responsible for the IFN-γ induction. Screening and titration of antigenic peptides or truncated derivatives identified the following antigenic regions: core₂₄₁₋₂₅₅ PESRKKLEKALLAWA and NS3₁₉₀₂₋₁₉₁₂ VEYSFIFLDEY, or minimal length antigenic peptides: E2₉₉₆₋₁₀₀₃ YEPRDSYF, NS2₁₂₂₃₋₁₂₃₀ STVTGIFL and NS5A₃₀₇₀₋₃₀₇₈ RVDNALLKF. The epitopes are highly conserved across CSFV strains and variable sequence divergence was observed with related pestiviruses. Characterisation of epitope-specific CD8 T cells revealed evidence of cytotoxicity, as determined by CD107a mobilisation, and a significant proportion expressed TNF-α in addition to IFN-γ. Finally, the variability in the antigen-specificity of these immunodominant CD8 T cell responses was confirmed to be associated with expression of distinct MHC class I haplotypes. Moreover, recognition of NS₁₂₂₃₋₁₂₃₀ STVTGIFL and NS3₁₉₀₂₋₁₉₁₂ VEYSFIFLDEY by a larger group of C-strain vaccinated animals showed

  5. Genetic clustering of recent classical swine fever virus isolates from Karnataka, India revealed the emergence of subtype 2.2 replacing subtype 1.1.

    Science.gov (United States)

    Shivaraj, D B; Patil, S S; Rathnamma, D; Hemadri, D; Isloor, S; Geetha, S; Manjunathareddy, G B; Gajendragad, M R; Rahman, H

    2015-09-01

    The phylogenetic analysis of 11 CSFV isolates from Karnataka, India obtained during the year 2012-13 was undertaken to obtain the most reliable genetic typing of the CSFV isolates based on E2, NS5B and 5'UTR genomic regions. The study indicated that all the 11 CSFV isolates belonged to subgroup 2.2. The most reliable classification was obtained with sequence data from the NS5B region which separated all the isolates based on the history of outbreak and geographic origin. Analysis of full length E2 amino acid sequences revealed different genetic makeup of Indian 2.2 isolates compared to 2.2 isolates from different countries. The group 2.2 viruses are gradually spreading as confirmed by frequent detection/ isolation of group 2.2 viruses in the recent years and replacing the subgroup 1.1 viruses, which were hitherto predominantly involved in CSF outbreaks in India. PMID:26396984

  6. Entomological profile of yellow fever epidemics in the Central African Republic, 2006-2010.

    OpenAIRE

    Ngoagouni, Carine; Kamgang, Basile; Manirakiza, Alexandre; Nangouma, Auguste; Paupy, Christophe; Nakoune, Emmanuel; Kazanji, Mirdad

    2012-01-01

    UNLABELLED: ABSTRACT: BACKGROUND: The causative agent of yellow fever is an arbovirus of the Flaviviridae family transmitted by infected Aedes mosquitoes, particularly in Africa. In the Central African Republic since 2006, cases have been notified in the provinces of Ombella-Mpoko, Ouham-Pende, Basse-Kotto, Haute-Kotto and in Bangui the capital. As the presence of a vector of yellow fever virus (YFV) represents a risk for spread of the disease, we undertook entomological investigations at the...

  7. Entomological profile of yellow fever epidemics in the Central African Republic, 2006–2010

    OpenAIRE

    Ngoagouni Carine; Kamgang Basile; Manirakiza Alexandre; Nangouma Auguste; Paupy Christophe; Nakoune Emmanuel; Kazanji Mirdad

    2012-01-01

    Abstract Background The causative agent of yellow fever is an arbovirus of the Flaviviridae family transmitted by infected Aedes mosquitoes, particularly in Africa. In the Central African Republic since 2006, cases have been notified in the provinces of Ombella-Mpoko, Ouham-Pende, Basse-Kotto, Haute-Kotto and in Bangui the capital. As the presence of a vector of yellow fever virus (YFV) represents a risk for spread of the disease, we undertook entomological investigations at these sites to id...

  8. Entomological profile of yellow fever epidemics in the Central African Republic, 2006–2010

    OpenAIRE

    Ngoagouni, Carine; Kamgang, Basile; Manirakiza, Alexandre; Nangouma, Auguste; Paupy, Christophe; Nakoune, Emmanuel; Kazanji, Mirdad

    2012-01-01

    UNLABELLED: ABSTRACT: BACKGROUND: The causative agent of yellow fever is an arbovirus of the Flaviviridae family transmitted by infected Aedes mosquitoes, particularly in Africa. In the Central African Republic since 2006, cases have been notified in the provinces of Ombella-Mpoko, Ouham-Pende, Basse-Kotto, Haute-Kotto and in Bangui the capital. As the presence of a vector of yellow fever virus (YFV) represents a risk for spread of the disease, we undertook entomological investigations at the...

  9. 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. Here, using the most comprehensive set of swine influenza virus antigenic data compiled to date, we quantify the antigenic diversity of swine influenza viruses on a multi-continental scale. The substantial antigenic diversity of recently circulating viruses in different parts of the world adds...

  10. Rapid Detection and Quantification of RNA of Ebola and Marburg Viruses, Lassa Virus, Crimean-Congo Hemorrhagic Fever Virus, Rift Valley Fever Virus, Dengue Virus, and Yellow Fever Virus by Real-Time Reverse Transcription-PCR

    OpenAIRE

    Drosten, Christian; Göttig, Stephan; Schilling, Stefan; Asper, Marcel; Panning, Marcus; Schmitz, Herbert; Günther, Stephan

    2002-01-01

    Viral hemorrhagic fevers (VHFs) are acute infections with high case fatality rates. Important VHF agents are Ebola and Marburg viruses (MBGV/EBOV), Lassa virus (LASV), Crimean-Congo hemorrhagic fever virus (CCHFV), Rift Valley fever virus (RVFV), dengue virus (DENV), and yellow fever virus (YFV). VHFs are clinically difficult to diagnose and to distinguish; a rapid and reliable laboratory diagnosis is required in suspected cases. We have established six one-step, real-time reverse transcripti...

  11. Global migration of influenza A viruses in swine

    Science.gov (United States)

    The emergence of the 2009 A/H1N1 pandemic virus underscores the importance of understanding how influenza A viruses evolve in swine on a global scale. To reveal the frequency, patterns and drivers of the spread of swine influenza virus globally, we conducted the largest phylogenetic analysis of swin...

  12. The global antigenic diversity of swine influenza A viruses

    OpenAIRE

    Lewis, Nicola S.; Russell, Colin A.; Langat, Pinky; Tavis K Anderson; Berger, Kathryn; Bielejec, Filip; Burke, David F.; Dudas, Gytis; Fonville, Judith M; Fouchier, Ron AM; Kellam, Paul; Koel, Bjorn F; Lemey, Philippe; Nguyen, Tung; Nuansrichy, Bundit

    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 antigeni...

  13. 猪瘟病毒和牛病毒性腹泻病毒双重RT-PCR方法的建立和初步应用%Establishment and Initially Application of Double RT-PCR Detection Method for Both Classical Swine Fever Virus and Bovine Viral Diarrhea Virus

    Institute of Scientific and Technical Information of China (English)

    陈静; 张小飞; 范红结; 黄显明

    2011-01-01

    根据GenBank上已发表的猪瘟病毒(CSFV)和牛病毒性腹泻病毒(BVDV)的全基因序列,进行对比分析,分别设计合成两对能特异性扩增CSFV、BVDV的引物.经过条件优化后,建立了检测(SFV和BVDV的双重RT-PCR方法,扩增两种病毒的片段,大小分别为938、650 bp.应用该方法对11批牛睾丸细胞、7批胎牛血清、60个批次的猪瘟细胞苗、10份全血样及10份组织样进行检测.通过试验证明,所建立的方法具有良好的特异性和敏感性,为防止猪瘟细胞苗的污染及进行CSFV和BVDV鉴别诊断提供了有效方法.%According to the complete genome sequences of classical swine fever virus (CSFV) and bovine viral diarrhea virus (BVDV) in GenBank, two pairs of primers were designed and synthesized. A double RT-PCR was developed based on these two pairs of primers which amplified the CSFV virus-specific segment with 938 bp and the BVDV virus-specific segment with 650 bp in sizes after the conditions of PCR were optimized. Approved this method of 11 batches of bovine testicular cells,7 batches of fetal bovine serum,60 batches of swine fever vaccine, 10 full-blood and 10 tissue samples for testing. The experiment showed that the developed method has good specificity and sensitivity of cell vaccine to prevent the pollution of BVDV and the diagnosis of CSFV and BVDV provides an effective method.

  14. 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

    virtually identical, confirming that the Paderborn isolate triggered the Dutch outbreak, and furthermore showing that this single isolate was stable throughout the whole Dutch outbreak (the above reviewed in [C. Terpstra, A. J. de Smit, Veterinary Microbiol. 77 (2000) 3-15]). We determined the nucleotide...... sequence of the 5' NTR (by 5' RACE) and the complete open reading frame of the Paderborn isolate (GenBank AY072924). Our sequence was identical to previously published partial 5'NTR and E2 sequences for the index Paderborn 1997 and Dutch 1997 (Venhorst) isolates, confirming the identity of the virus we....... Paderborn is the only recent European CSFV field isolate for which a complete sequence is available, and given Paderborns genetic and antigenic uniqueness, the Paderborn sequence may have practical use for diagnostic and vaccine antigen development....

  15. Modeling Classical Swine Fever Outbreak-Related Outcomes.

    Science.gov (United States)

    Yadav, Shankar; Olynk Widmar, Nicole J; Weng, Hsin-Yi

    2016-01-01

    The study was carried out to estimate classical swine fever (CSF) outbreak-related outcomes, such as epidemic duration and number of infected, vaccinated, and depopulated premises, using defined most likely CSF outbreak scenarios. Risk metrics were established using empirical data to select the most likely CSF outbreak scenarios in Indiana. These scenarios were simulated using a stochastic between-premises disease spread model to estimate outbreak-related outcomes. A total of 19 single-site (i.e., with one index premises at the onset of an outbreak) and 15 multiple-site (i.e., with more than one index premises at the onset of an outbreak) outbreak scenarios of CSF were selected using the risk metrics. The number of index premises in the multiple-site outbreak scenarios ranged from 4 to 32. The multiple-site outbreak scenarios were further classified into clustered (N = 6) and non-clustered (N = 9) groups. The estimated median (5th, 95th percentiles) epidemic duration (days) was 224 (24, 343) in the single-site and was 190 (157, 251) and 210 (167, 302) in the clustered and non-clustered multiple-site outbreak scenarios, respectively. The median (5th, 95th percentiles) number of infected premises was 323 (0, 488) in the single-site outbreak scenarios and was 529 (395, 662) and 465 (295, 640) in the clustered and non-clustered multiple-site outbreak scenarios, respectively. Both the number and spatial distributions of the index premises affected the outcome estimates. The results also showed the importance of implementing vaccinations to accommodate depopulation in the CSF outbreak controls. The use of routinely collected surveillance data in the risk metrics and disease spread model allows end users to generate timely outbreak-related information based on the initial outbreak's characteristics. Swine producers can use this information to make an informed decision on the management of swine operations and continuity of business, so that potential losses could

  16. Modeling classical swine fever outbreak-related outcomes

    Directory of Open Access Journals (Sweden)

    Shankar eYadav

    2016-02-01

    Full Text Available The study was carried out to estimate classical swine fever (CSF outbreak-related outcomes such as epidemic duration and number of infected, vaccinated, and depopulated premises, using defined most likely CSF outbreak scenarios. Risk metrics were established using empirical data to select the most likely CSF outbreak scenarios in Indiana. The scenarios were simulated using a stochastic between-premises disease spread model to estimate outbreak-related outcomes. A total of 19 single-site (i.e., with a single-index premises at the onset of an outbreak and 15 multiple-site (i.e., with more than one index premises at the onset of an outbreak outbreak scenarios of CSF were selected using the risk metrics. The number of index premises in the multiple-site outbreak scenarios ranged from 4 to 32. The multiple-site outbreak scenarios were further classified into clustered (N=6 and non-clustered (N=9 groups. The estimated median (5th, 95th percentiles epidemic duration (days was 224 (24, 343 in the single-site and was 190 (157, 251 and 210 (167, 302 in the clustered and non-clustered multiple-site outbreak scenarios, respectively. The median (5th, 95th percentiles number of infected premises was 323 (0, 488 in the single-site outbreak scenarios and was 529 (395, 662 and 465 (295, 640 in the clustered and non-clustered multiple-site outbreak scenarios, respectively. Both the number and spatial distribution of the index premises affected the outcome estimates. The results also showed the importance of implementing vaccinations to accommodate depopulation in the CSF outbreak controls. The use of routinely collected surveillance data in the risk metrics and disease spread model allows end users to generate timely outbreak-related information based on the initial outbreak’s characteristics. Swine producers can use this information to make an informed decision on management of swine operations and continuity of business so that potential losses could be

  17. The swine CD81 enhances E2-based DNA vaccination against classical swine fever.

    Science.gov (United States)

    Li, Wenliang; Mao, Li; Zhou, Bin; Liu, Xia; Yang, Leilei; Zhang, Wenwen; Jiang, Jieyuan

    2015-07-01

    Classical swine fever (CSF) is a highly contagious and economically important viral disease that affects the pig industry worldwide. The glycoprotein E2 of CSFV can induce neutralizing antibodies and protective immunity, and is widely used for novel vaccine development. The objective of this study was to explore whether a tetraspanin molecule CD81 could improve the immune responses of an E2-based DNA vaccine. Plasmids pVAX-CD81, pVAX-E2 and pVAX-CD81-E2 were constructed and the expression of target proteins was confirmed in BHK-21 cells by indirect immunofluorescence assay. BALB/c mice were divided into 5 groups and immunized with different plasmids (pVAX-E2, pVAX-CD81-E2, pVAX-E2+pVAX-CD81, pVAX-CD81 and PBS) three times with two weeks interval. The results showed that the introduction of CD81 promoted higher humoral and cellular immune responses than E2 expression alone (P<0.05). In addition, immunization with pVAX-CD81-E2 induced stronger immune responses than pVAX-E2+pVAX-CD81. Furthermore, four groups of pigs were immunized with pVAX-E2, pVAX-CD81-E2, pVAX-CD81 and PBS, respectively. Humoral and cellular immune responses detection showed similar results with those in mice. Compared to pVAX-E2, pVAX-CD81-E2 induced higher titers of neutralizing antibodies after viral challenge and conferred stronger protection. These results confirmed the capacity of swine CD81 enhancing the humoral and cellular responses with an adjuvant effect on CSFV DNA vaccine. This is the first report demonstrating the adjuvant effect of CD81 to enhance the DNA vaccination for swine pathogen. PMID:26051512

  18. Enemies and turncoats: bovine tuberculosis exposes pathogenic potential of Rift Valley fever virus in a common host, African buffalo (Syncerus caffer).

    Science.gov (United States)

    Beechler, B R; Manore, C A; Reininghaus, B; O'Neal, D; Gorsich, E E; Ezenwa, V O; Jolles, A E

    2015-04-22

    The ubiquity and importance of parasite co-infections in populations of free-living animals is beginning to be recognized, but few studies have demonstrated differential fitness effects of single infection versus co-infection in free-living populations. We investigated interactions between the emerging bacterial disease bovine tuberculosis (BTB) and the previously existing viral disease Rift Valley fever (RVF) in a competent reservoir host, African buffalo, combining data from a natural outbreak of RVF in captive buffalo at a buffalo breeding facility in 2008 with data collected from a neighbouring free-living herd of African buffalo in Kruger National Park. RVF infection was twice as likely in individual BTB+ buffalo as in BTB- buffalo, which, according to a mathematical model, may increase RVF outbreak size at the population level. In addition, co-infection was associated with a far higher rate of fetal abortion than other infection states. Immune interactions between BTB and RVF may underlie both of these interactions, since animals with BTB had decreased innate immunity and increased pro-inflammatory immune responses. This study is one of the first to demonstrate how the consequences of emerging infections extend beyond direct effects on host health, potentially altering the dynamics and fitness effects of infectious diseases that had previously existed in the ecosystem on free-ranging wildlife populations. PMID:25788592

  19. [Classical Swine Fever in wild boar in Rhineland-Palatinate: evaluation of the official control measures from 2005-2011].

    Science.gov (United States)

    Romelt, Maria; Klingelhefer, Irene; Konig, Astrid; Braun, Bettina; Reiner, Gerald

    2015-01-01

    The present study describes the control strategy for fighting Classical Swine Fever in wild boar in Rhineland-Palatinate from 2005 to 2011 and evaluates its effectiveness. The official control measures were based on the following three main pillars:--Serological and virological monitoring: By means of serological monitoring Classical Swine Fever outbreaks could be detected very early. Increasing antibody prevalences indicated an imminent Classical Swine Fever outbreak. This could be confirmed by the virological investigations. The geographical evaluations of the virological investigations showed that the outbreaks occurred only in localized areas and a spreading of the virus had not taken place yet or could be prevented.--Oral immunization: After virological detection of Classical Swine Fever Virus oral immunization was started immediately. This oral immunization achieved antibody prevalence rates of 57% on an average. The analysis of the distribution of the antibodies in the vaccination areas concerning the different age groups in the vaccination areas showed that 41% of the young animals, 66% of animals from one to two years and 77% of the adult animals were immunized.--Hunting measures: For the reduction of the wild boar population an all-year, intensive hunt with special attention to the young animals and the female animals was carried out. The hunting bag increased on more than 80 000 wild boar per hunting season. Out of the total 108,772 hunted wild boar were 47% of young animals, 40% of animals from one to two years and 13% of adult animals. Concerning the gender distribution on an average 53% female and 47% male animals were shot. in summary, the current control strategy was effective because there had been no further proof of Classical Swine Fever in wild boar in Rhineland-Palatinate since 2009. Nevertheless, the fight strategy can be optimized even further. For an optimum monitoring the development of a marker vaccine which allows a differentiation of

  20. O surto de peste suína africana ocorrido em 1978 no município de Paracambi, Rio de Janeiro The outbreak of African swine fever which ocurred in 1978 in the county of Paracambi, Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    Carlos Hubinger Tokarnia

    2004-12-01

    caracterização do virus, bem como na ausência de dados sobre epidemiologia, sinais clínicos e patologia nesses outros supostos focos, pode-se concluir que o surto de Paracambi constitui a única ocorrência de PSA no Brasil, comprovada por isolamento, identificação do vírus e determinação de sua patogenicidade, e que a doença manteve-se confinada a esse local, provavelmente em função do diagnóstico precoce e da rápida adoção de eficientes medidas de controle pelas autoridades sanitárias; o abate dos suínos desse rebanho iniciou-se 10 dias depois da primeira morte e 3 dias após o diagnóstico presuntivo.Due to doubts which still persist 25 years after the outbreak of African swine fever (ASF which ocurred in the county of Paracambi, Rio de Janeiro, Brazil, in 1978, the results obtained through the studies to establish and confirm the diagnosis are presented. These include data on the epidemiology, clinic-pathological aspects, bacteriological, virological and ultramicroscopic examinations, the experimental reproduction of the disease and cross immunity tests with classical swine fever virus performed in Brazil, and on the confirmation with isolation of the virus and determination of its identity at the Plum Island Animal Disease Center, New York, USA. The pigs of the affected herd had been fed untreated remains of meals from airplanes of international lines flying to Brazil from Portugal and Spain where ASF was occurring at the time. According to publication by the Ministry of Agriculture, after the diagnosis of the outbreak of ASF described in this paper, 223 additional outbreaks were reported in Brazil between 1978 and 1979, in all the Brazilian regions (North, Northeast, Central-West, Southeast and South. Further outbreaks were reported in 1981, but their number is not known. The last case was reported to have occurred on November 15, 1981, and on December 5, 1984, Brazil was declared free of ASF. For the diagnosis of ASF 54,002 samples were examined by

  1. Establishment and application of a multiplex PCR for rapid and simultaneous detection of six viruses in swine.

    Science.gov (United States)

    Zeng, Zhiyong; Liu, Zhijie; Wang, Weicheng; Tang, Deyuan; Liang, Haiying; Liu, Zhao

    2014-11-01

    A multiplex PCR assay was developed and evaluated subsequently for its effectiveness in simultaneously detecting mixed viral infections of swine. Specific primers were designed and used for testing the six swine viruses: three DNA viruses, including pseudorabies virus (PRV), porcine parvovirus (PPV), and porcine circovirus type 2 (PCV2); three common RNA viruses, including porcine reproductive and respiratory syndrome virus (PRRSV), classical swine fever virus (CSFV), and Japanese encephalitis virus (JEV). This technique has shown to be highly sensitive in that the minimum detection amounts of nucleic acids from PRV, PPV, PCV2, PRRSV, CSFV, and JEV were 6.6, 96, 12.9, 10.5, 51, and 46 pg, respectively. It also was effective for detecting one or multiple viruses in the specimens, such as the lungs, spleens, lymph nodes, and tonsils collected from clinically ill pigs. The multiplex PCR method can detect simultaneously not only infection of the six viruses, but also other swine DNA and RNA viruses. Given its rapidity, specificity, and sensitivity, the multiplex PCR is a useful tool for diagnosing clinically the mixed infections of swine DNA and RNA viruses. PMID:25116201

  2. Prokaryotic Expression and Identification of the Main Antigenic Domain Gene in NS2-3 of Classical Swine Fever Virus%猪瘟病毒NS2-3抗原集中区基因的原核表达及鉴定

    Institute of Scientific and Technical Information of China (English)

    刘卫; 朱艳平; 宁红梅; 银梅; 郭东光; 鲁毅; 王选年

    2013-01-01

    To identify the main antigen domain of the classical swine fever virus (CSFV) NS2-3, a method of detecting antibody of classical swine fever virus was established. CSFV genome plasmid as PCR template, the main antigenic domain of CSFV NS2-3 was amplified by PCR, amd PCR products was cloned into prokaryotic expression plasmid pET-32a(+) vector to obtain the recombinant expression plasmid, named as pET32a-NS2-3-1. The recombinant expression plasmid was transformed into E. coli Rosetta (DE3) and inducible expression by IPTG. The expression products were analyzed by SDS-PAGE and identified by Western-blot. The recombinant plasmid pET32a-NS2-3-1 was highly expressed, induced 5 hours could get a large number of recombinant protein at 28℃, and the recombinant protein reacted strongly with the C-Positive serum of CSFV. The main antigenic domain protein in NS2-3 of CSFV was obtained, which has good antigenicity for detecting antibodies against CSFV.%  为获得猪瘟病毒(classical swine fever virus, CSFV) NS2-3抗原集中区蛋白,并建立CSFV抗体快速检测方法.本研究以CSFV全长基因组质粒为模板,PCR扩增NS2-3抗原表位集中区,利用扩增片段和克隆载体,构建重组表达质粒,命名为pET32a-NS2-3-1.重组表达质粒转化Rosetta (DE3)细胞,利用IPTG诱导表达, SDS-PAGE电泳和Western-blot鉴定重组表达产物.结果表明,重组质粒pET32a-NS2-3-1在28℃诱导5 h得到高效表达,重组蛋白能够与兔抗CSFV阳性血清发生反应.获得CSFV NS2-3抗原集中区蛋白,并且获得的重组蛋白具有抗原性,能够作为CSFV抗体检测的抗原.

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

    OpenAIRE

    P. D. Luka; A. R. Jambol; B. Yakubu

    2014-01-01

    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 ...

  4. Establishment and Application of Real-time Fluorogenetic Quantitative RT-PCR for Detection of Classical Swine Fever Virus%猪瘟病毒实时荧光定量RT-PCR

    Institute of Scientific and Technical Information of China (English)

    李军; 杨威; 潘艳; 禤雄标; 胡帅; 马春霞; 谢宇舟; 陈泽样; 许力干; 谢永平

    2011-01-01

    根据GenBank公布的猪瘟病毒基因组5'非编码区基因序列进行同源性比较分析,选择保守序列区作为扩增区域,设计1对特异性扩增引物,通过优化反应条件,建立了一个用于猪瘟病毒快速定量检测的SY13R GreenⅠ荧光定量RT-PC R方法.试验结果表明该方法重复性好,反应批内循环阈值差异不显著.与猪繁殖与呼吸综合征病毒、伪狂犬病病毒和猪圆环病毒2型等猪源病毒无交叉反应,具有高度的特异性,而且灵敏度高,最小检出量为2×10(2)病毒基因组拷贝数.利用此方法对15例临床样本进行检测,其结果与兔体交又免疫试验一致,表明此方法可作为猪瘟实验室快速诊断和疫情监测的一种快速、准确、简便的检测工具.%To establish a real-time fluorogenetic quantitative RT-PCR assay for detection of classical swine fever virus (CSFV), the 5' non-translated region sequences of CSFV in GenBank were aligned and a pair of specific primers was designed from the conserved sequence within 5' non-translated region.The reactive conditions were optimized to improve the sensitivity and specificity of the assay.The results of reproducibility of this assay were reliable and the intra assay variations were not significant.The specificity test proved that this assay had a high specificity which could not detected PRRSV,PRV and PCV2.The assay also proven to be specific,and the detection limit was up to 2 × 102 copies.The accuracy of real-time fluorogenetic quantitative RT-PCR was evaluated by testing 15 clinical samples.The results of real-time fluorogenetic quantitative RT-PCR were consistent with results of rabbit-cross reaction test,which suggested that real-time quantitative RT-PCR assay may be used as a powerful tool for repaid detection of CSFV.

  5. The global antigenic diversity of swine influenza A viruses

    Science.gov (United States)

    Lewis, Nicola S; Russell, Colin A; Langat, Pinky; Anderson, Tavis K; Berger, Kathryn; Bielejec, Filip; Burke, David F; Dudas, Gytis; Fonville, Judith M; Fouchier, Ron AM; Kellam, Paul; Koel, Bjorn F; Lemey, Philippe; Nguyen, Tung; Nuansrichy, Bundit; Peiris, JS Malik; Saito, Takehiko; Simon, Gaelle; Skepner, Eugene; Takemae, Nobuhiro; Webby, Richard J; Van Reeth, Kristien; Brookes, Sharon M; Larsen, Lars; Watson, Simon J; Brown, Ian H; Vincent, Amy L

    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. Here, using the most comprehensive set of swine influenza virus antigenic data compiled to date, we quantify the antigenic diversity of swine influenza viruses on a multi-continental scale. The substantial antigenic diversity of recently circulating viruses in different parts of the world adds complexity to the risk profiles for the movement of swine and the potential for swine-derived infections in humans. DOI: http://dx.doi.org/10.7554/eLife.12217.001 PMID:27113719

  6. Crimean-Congo hemorrhagic fever virus, Greece.

    Science.gov (United States)

    Papa, Anna; Sidira, Persefoni; Larichev, Victor; Gavrilova, Ludmila; Kuzmina, Ksenia; Mousavi-Jazi, Mehrdad; Mirazimi, Ali; Ströher, Ute; Nichol, Stuart

    2014-02-01

    Seroprevalence of Crimean-Congo hemorrhagic fever virus (CCHFV) is high in some regions of Greece, but only 1 case of disease has been reported. We used 4 methods to test 118 serum samples that were positive for CCHFV IgG by commercial ELISA and confirmed the positive results. A nonpathogenic or low-pathogenicity strain may be circulating. PMID:24447877

  7. Enzootic Transmission of Yellow Fever Virus, Venezuela

    OpenAIRE

    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.

  8. History of ‘swine fever’ in Southern Africa

    OpenAIRE

    Mary-Louise Penrith

    2013-01-01

    The histories of the two swine fevers in southern Africa differ widely. Classical swine fever (hog cholera) has been known in the northern hemisphere since 1830 and it is probable that early cases of ‘swine fever’ in European settlers’ pigs in southern Africa were accepted to be that disease. It was only in 1921 that the first description of African swine fever as an entity different from classical swine fever was published after the disease had been studied in settlers’ pigs in Kenya. Shortl...

  9. History of ‘swine fever’ in Southern Africa

    Directory of Open Access Journals (Sweden)

    Mary-Louise Penrith

    2013-02-01

    Full Text Available The histories of the two swine fevers in southern Africa differ widely. Classical swine fever (hog cholera has been known in the northern hemisphere since 1830 and it is probable that early cases of ‘swine fever’ in European settlers’ pigs in southern Africa were accepted to be that disease. It was only in 1921 that the first description of African swine fever as an entity different from classical swine fever was published after the disease had been studied in settlers’ pigs in Kenya. Shortly after that, reports of African swine fever in settlers’ pigs emerged from South Africa and Angola. In South Africa, the report related to pigs in the north-eastern part of the country. Previously (in 1905 or earlier a disease assumed to be classical swine fever caused high mortality among pigs in the Western Cape and was only eradicated in 1918. African swine fever was found over the following years to be endemic in most southern African countries. Classical swine fever, however, apart from an introduction with subsequent endemic establishment in Madagascar and a number of introductions into Mauritius, the last one in 2000, had apparently remained absent from the region until it was diagnosed in the Western and subsequently the Eastern Cape of South Africa in 2005. It was eradicated by 2007. The history of these diseases in the southern African region demonstrates their importance and their potential for spread over long distances, emphasising the need for improved management of both diseases wherever they occur.

  10. New knowledge in application of vaccines with Kina(Kstrain in control and curbing of classical swine fever

    Directory of Open Access Journals (Sweden)

    Prodanov Jasna

    2006-01-01

    Full Text Available The program of curbing and outrooting classical swine fever (CSF in our country has for years been based on the vaccination of all categories of swine with the Kina (K strain of the CSF virus, and, after the establishment of the source of infection, with the non-harmful removal of the infected swine herd, as well as on the implementation of all measures prescribed by the valid regulations. However, in spite of the implementation of all the listed measures, CSF still occurs continually. The epizootiological situation in our country in the course of 2005 was extremely unfavorable from the aspect of the number of identified CSF crisis spots, and it can be pointed out at this time that the disease was diagnosed clinically, pathomorphologically and using laboratory methods in 51 farms in a single examined epizootiological district. Under conditions when CSF appears continually throughout the year, vaccination using a modified live vaccine must continue being the basic measure in preventing the appearance, spreading, curbing, and eradication of CSF. With the objective of securing a concept of the most efficient further strategy for control and curbing of this disease, the paper presents the most important aspects regarding efficacy, safety, as well as field experience in applying vaccines which are based on the K strain of the CSF virus. .

  11. Epidemiological and economic modelling of classical swine fever: application to the 1997/1998 Dutch epidemic

    NARCIS (Netherlands)

    Mangen, M.J.J.; Burrell, A.M.; Mourits, M.C.M.

    2004-01-01

    This paper describes a modelling system developed to simulate the epidemiological and economic effects of a classical swine fever (CSF) epidemic in the Netherlands. The system consists of four interlinked models plus a spreadsheet. The models are characterised by different levels of spatial and temp

  12. Economic aspects of antiviral agents to control Classical Swine Fever epidemics

    OpenAIRE

    Bergevoet, R.H.M.; Asseldonk, van, N.; Backer, J.A.

    2012-01-01

    Outbreaks of contagious animal diseases such as Classical Swine Fever have detrimental effects on the livestock sector in an affected country as well as on society at large. The development of antiviral agents to control these epidemics can reduce the consequences of such outbreaks. The economic impact of applying these antiviral agents is until now unknown. In this report these consequences are investigated.

  13. AN ANALYTICAL FRAMEWORK FOR DISCUSSING FARM BUSINESS INTERRUPTION INSURANCE FOR CLASSICAL SWINE FEVER

    OpenAIRE

    M.P.M. Meuwissen; Skees, J.R.; Black, J R; Huirne, R.B.M.; Dijkhuizen, A.A.

    2000-01-01

    This paper studies farm business interruption insurance for Classical Swine Fever epidemics. Insight into the size of risk is obtained by a very detailed Monte-Carlo simulation model that includes both epidemiological and economic factors. The paper also considers issues such as farmers' and governments' influence on the size of risk.

  14. Zika virus and Zika fever.

    Science.gov (United States)

    Wang, Zhaoyang; Wang, Peigang; An, Jing

    2016-04-01

    An emerging mosquito-borne arbovirus named Zika virus (ZIKV), of the family Flaviviridae and genus Flavivirus, is becoming a global health threat. ZIKV infection was long neglected due to its sporadic nature and mild symptoms. However, recently, with its rapid spread from Asia to the Americas, affecting more than 30 countries, accumulating evidences have demonstrated a close association between infant microcephaly and Zika infection in pregnant women. Here, we reviewed the virological, epidemiological, and clinical essentials of ZIKV infection. PMID:27129450

  15. Epidemic Reasons and Recommendations of Prevention and Control about Classical Swine Fever%猪瘟的流行原因及其防控建议

    Institute of Scientific and Technical Information of China (English)

    黄江峰; 江岸林; 杨晓天; 李纪春

    2011-01-01

    @@ 猪瘟(Classical SwiHe fever,CSF)是由猪瘟病毒(Classical swine fever virus,CSFV)引起猪的一种高度接触性、致死性的传染病.高热稽留,便秘与拉稀交替,死亡率高是其主要特征.目前,主要有非典型性猪瘟和繁殖障碍性猪瘟两种类型.

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

    DEFF Research Database (Denmark)

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

    The Danish surveillance program for influenza A virus in pigs has revealed that two novel reassortant swine influenza viruses may now be circulating in the Danish swine population, since they each have been detected in at least two submissions from different herds in 2011 as well as in 2012. One 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...... pandemic H1N1pdm09 influenza virus lineage. Swine influenza virus with a similar subtype to H1pdm09N2sw has previously been found in pigs in Italy and Germany. Detailed analyses of viral genes will further elucidate the relationship between these new swine influenza viruses found in the different countries...

  17. 激流灌注式生物反应器培养猪瘟活疫苗工艺的研究%Research of Classical Swine Fever Vaccine Technology with Suspension and Perfusion Bioreactor

    Institute of Scientific and Technical Information of China (English)

    郑朝朝; 柳珊; 邹立宏; 刘云涛; 刘涛; 郁宏伟

    2016-01-01

    为建立规模化培养猪瘟活疫苗的生产工艺,本研究利用工作体积为10L的激流灌注式生物反应器培养猪睾丸细胞(swine testis, ST),接种猪瘟病毒(classical swine fever virus, CSFV)进行培养研究。研究结果显示,培养4 d细胞数可增长5~7倍,接种病毒后15 d可收获毒液6次,收获量至少与200个10 L转瓶单次收获量相当,产品各项检测均合格。本工艺极大地缩短了培养时间,为规模化培养工艺的推广与使用提供了技术参数。%In order to establish large- scale cultivation of swine fever vaccine production process, this re-search applied 10 L volume of suspension and perfusion bioreactor to culture swine testicular cells, vaccinate classical swine fever virus. Results showed that the number of cells increased 5 to 7 times within 4 days, classical swine fever virus could be harvested 6 times within 15 days, and the classical swine fever vaccine could satisfy all the biological qualifications and requirements. This technology could greatly shorten the training time and it will be the basis to such scale vaccine antigen production.

  18. An update on safety studies on the attenuated "RIEMSER Schweinepestoralvakzine" for vaccination of wild boar against classical swine fever.

    Science.gov (United States)

    Kaden, Volker; Lange, Elke; Küster, Heike; Müller, Thomas; Lange, Bodo

    2010-07-14

    The RIEMSER Schweinepestoralvakzine is an attenuated vaccine for oral vaccination of wild boar against classical swine fever (CSF). The safety of this licensed bait vaccine which is based on the CSF virus (CSFV) strain "C" was investigated in eight animal species, e.g. weaner pigs (n=111), wild boar (n=11), ruminants (cattle, goats and sheep, n=11), foxes (n=5), rabbits (n=12), and mice (n=10). Animals were vaccinated either with a single vaccine dose containing at least 10(4.5) TCID(50), or with overdoses, i.e. the 10-fold dose, or they were subjected to repeated application schemes. During the entire observation period none of the animals which were given the vaccine virus showed clinical signs, with the exception of rabbits. These reacted to the vaccination with fever. Orally vaccinated pigs did not transmit vaccine virus to susceptible contact animals (sentinels). In none of the species examined neither vaccine virus nor viral RNA could be detected in blood after vaccination. In one wild boar viral RNA could be established in the tonsil 21 days post-vaccination (dpv); all other organ samples tested virologically negative. Up to 77.5% of the pigs and wild boar developed virus neutralising antibodies (VNA) already 14 dpv. The mean VNA titres observed in the vaccination groups seemed to depend rather on individual factors than on the administered virus dose (virus titre per dose) or the vaccination scheme. These results are comparable with findings obtained during oral vaccination campaigns in wild boar and after parenteral vaccination with this C-strain virus. From the results presented here it can be concluded that RIEMSER Schweinepestoralvakzine is safe for target and non-target species. PMID:20022716

  19. 猪瘟疫苗质量的替代检验方法研究进展%Progress on New Alternative Test Method for Quality Inspection of Classical Swine Fever Vaccine

    Institute of Scientific and Technical Information of China (English)

    祖立闯; 吴信明; 谢金文; 沈志强; 李娇; 唐娜; 王金良; 苗立中; 张娜; 王艳

    2015-01-01

    国标的猪瘟疫苗效力检验、支原体检验、外源病毒检验等质量检验方法均存在试验周期长、操作繁琐、敏感性较低等缺点,随着现代免疫学与分子生物学技术的快速发展,猪瘟疫苗质量检验的新兴替代检验方法日臻发展和完善。论文就近年来针对猪瘟病毒的病毒含量测定、猪瘟疫苗效力检验、支原体检验、外源病毒检验等免疫学与分子生物学新兴检测方法的研究进展做一综述,以期为提高猪瘟疫苗的质量检验水平、保障猪瘟疫苗质量提供参考依据。%the national classical swine fever vaccine potency test ,Mycoplasma inspection ,exogenous virus test quality inspection method existed long test cycle ,complicated operation ,and low sensitivity ,with the rapid development of modern immunology and molecular biology technology ,the emerging alternative test methods for classical swine fever vaccine quality inspection gradual development and improvement .This paper makes a review of the new detection methods for recent immunology and molecular biology research progress on the classical swine fever virus content determination ,classical swine fever vaccine potency test ,Mycoplasma inspection ,exogenous virus test ,in order to provide the reference basis for improving the level of quality inspection of classical swine fever vaccine ,guarantee the quality of classical swine fever vaccine .

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

    OpenAIRE

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

    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 CS...

  1. Protection against yellow fever in monkeys by immunization with yellow fever virus nonstructural protein NS1.

    OpenAIRE

    Schlesinger, J J; Brandriss, M. W.; Cropp, C.B.; Monath, T. P.

    1986-01-01

    Immunization of monkeys with yellow fever virus-specified nonstructural protein NS1 resulted in protection against fatal hepatitis as well as marked reduction in the magnitude of viremia after subcutaneous challenge with yellow fever virus. The results may be relevant to the design of possible subunit or recombinant flavivirus vaccines.

  2. Yellow fever, Asia and the East African slave trade.

    Science.gov (United States)

    Cathey, John T; Marr, John S

    2014-05-01

    Yellow fever is endemic in parts of sub-Saharan Africa and South America, yet its principal vectors--species of mosquito of the genus Aedes--are found throughout tropical and subtropical latitudes. Phylogenetic analyses indicate that yellow fever originated in Africa and that its spread to the New World coincided with the slave trade, but why yellow fever has never appeared in Asia remains a mystery. None of several previously proposed explanations for its absence there is considered satisfactory. We contrast the trans-Atlantic slave trade, and trade across the Sahara and to the Arabian Peninsula and Mesopotamia, with that to Far East and Southeast Asian ports before abolition of the African slave trade, and before the scientific community understood the transmission vector of yellow fever and the viral life cycle, and the need for shipboard mosquito control. We propose that these differences in slave trading had a primary role in the avoidance of yellow fever transmission into Asia in the centuries before the 20(th) century. The relatively small volume of the Black African slave trade between Africa and East and Southeast Asia has heretofore been largely ignored. Although focal epidemics may have occurred, the volume was insufficient to reach the threshold for endemicity. PMID:24743951

  3. Influenza Virus Surveillance in Coordinated Swine Production Systems, United States.

    Science.gov (United States)

    Kaplan, Bryan S; DeBeauchamp, Jennifer; Stigger-Rosser, Evelyn; Franks, John; Crumpton, Jeri Carol; Turner, Jasmine; Darnell, Daniel; Jeevan, Trushar; Kayali, Ghazi; Harding, Abbey; Webby, Richard J; Lowe, James F

    2015-10-01

    To clarify the epidemiology of influenza A viruses in coordinated swine production systems to which no animals from outside the system are introduced, we conducted virologic surveillance during September 2012-September 2013. Animal age, geographic location, and farm type were found to affect the prevalence of these viruses. PMID:26402228

  4. VIRUS VACCINE RESEARCH AT THE NATIONAL ANIMAL DISEASE CENTER: LESSONS FROM SWINE INFLUENZA VIRUS AND BOVINE VIRAL DIARRHEA VIRUS

    Science.gov (United States)

    The continuing emergence of novel subtypes and genetic variants of swine influenza viruses (SIV) causing swine flu challenges our ability to effectively manage this high morbidity disease among swine. New strategic approaches for vaccine development must be considered to keep up with the ever-evolv...

  5. 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

  6. Economic aspects of C-strain vaccination to control Classical Swine Fever epidemics

    OpenAIRE

    Bergevoet, R.H.M.; Asseldonk, van, N.

    2013-01-01

    In dit onderzoek zijn de verschillen in economische effecten van noodvaccinatie bij een uitbraak van Klassieke Varkenspest (KVP) in een veedichtgebied in Nederland onderzocht. Hierbij is een levend vaccin gebaseerd op de C-stam vergeleken met het vaccin dat op het moment als voorkeurvaccin genoemd wordt in de bestrijdingsdraaiboeken (het E2 subunit vaccin).This research is focused on economic differences of emergency vaccination in case of an outbreak of Classical Swine Fever (CSF) in a dense...

  7. Risk Approximate Based Studies on the Current Status of Global Pattern of African Swine Fever and Its Import Risk Model%基于"风险邻近"的全球尺度非洲猪瘟发生状况及其输入风险模型构建

    Institute of Scientific and Technical Information of China (English)

    张志诚; 黄炯; 包静月; 张永强; 钟旗; 王力俭; 王志亮; 李长友

    2011-01-01

    达、安哥拉、肯尼亚、尼日利亚、南非、坦桑尼亚、赞比亚等国家.从非洲猪瘟风险国家输入猪及其产品会带来一定的输入风险.有效强化产地检疫,开展风险区划,对非洲猪瘟等疫病的风险管理具有重要的意义.%Global pattern of current status of African swine fever (ASF) were explored, and its import risk model were constructed and derived. Based on the data mining techniques and probability risk theory, methods of Geography risk analysis, the first law of geography and risk approximate theory were applied in this manuscript. Results were as follows: In Global Scale, the swine production were mainly distributed in China, United States, Brazil, Canada, German, Spain, and French, the combination swine inventory of above country account for 76. 67% of global proportions,among which most density region were Spain, German, Netherlands and Belgium in EU,and China, Vietnam in Asian. Based on the Toble's first law of geography, "risk approximate" were introduced in this manuscript for the animal disease risk management and vet epidemiology, it's means that risk can be more approximated in the neighborhood than in distance. ASF have been recorded reported at least 89 frequency globally up to now, among which the countries like Guinea-Bissau, Namibia, Russia, Senegal, Benin, Burkina Faso, Cape Verde, Ghana, Italy, Madagascar, Mozambique and Togo have three years consecutive reported cases of ASF since 2007. Based on the Toble's first law of geography and risk approximated theory, the population above can be regarded as the most risk population country for African swine fever. Import swine and its products from countries at risk of ASF can pose risk to the imported countries, the imported risk (one batch of imported products) model can be depicted as follows: Pinport =f1·(1-Se) + (1-f1)f2·(l-Se)+(1-f1)·(1-f2).f3.(1-Se) +(1-f1).(1-f2).(1-f3).f4. (1-Se)+ (1-f1). (l-f2). (1-f3). (1-f4). F5. (1-Se) , among which f1

  8. Evaluation of the oral immunisation of wild boar against classical swine fever in Baden-Württemberg.

    Science.gov (United States)

    Kaden, Volker; Renner, Christiane; Rothe, Anke; Lange, Elke; Hänel, Andreas; Gossger, Klaus

    2003-01-01

    The oral immunisation of wild boar against classical swine fever (CSF) in Baden-Württemberg is described and evaluated. The bait vaccine based on the CSF virus (CSFV) strain "C" proved to be safe in wild boar of all age classes. The modified immunisation procedure consisting of three double vaccinations per year was very effective. CSFV was not detected beyond the second immunisation campaign. The average rate of seropositive wild boar diagnosed over all immunisation periods was 49.2%. The seroprevalence rate increased significantly during the first year of immunisation and reached its maximum after the third vaccination period with 72% antibody positive animals. The higher percentage of seropositive young boars in this field trial compared to the seroprevalence rates in this age class in other field trials in Germany may be attributed to the new vaccination scheme. Factors that may be responsible for the decreased herd immunity after the fourth or sixth immunisation period are discussed. PMID:14526465

  9. The Relationship Between Monthdisease Incidence Rate and Climatic Factor of Classical Swine Fever

    Science.gov (United States)

    Wang, Hongbin; Xu, Danning; Xiao, Jianhua; Zhang, Ru; Dong, Jing

    The Swine Fever is a kind of acute, highly infective epidemic disease of animals; it is name as Classical Swine Fever (CSF) by World animal Health organization. Meteorological factors such as temperature, air pressure and rainfall affect the epidemic of CSF significantly through intermediary agent and CSF viral directly. However there is significant difference among different region for mode of effects. Accordingly, the analyze must adopt different methods. The dependability between incidence rate each month of CSF and meteorological factors from 1999 to 2004 was analyzed in this paper. The function of meteorological factors on CSF was explored and internal law was expected to be discovered. The correlation between the incidence rate of Swine Fever and meteorological factors, thus the foundation analysis of the early warning and the decision-making was made, the result indicated that the incidence rate of CSF has negative correlation with temperature, rainfall, cloudage; relative humidity has positive correlation with disease; for air pressure, except average air pressure of one month, other air pressure factors have positive correlation with disease; for wind speed, except Difference among moths of wind speed and average temperature of one month. have positive correlation with disease, other wind speed factors has negative correlation with disease.

  10. Identification of Cytotoxic T Lymphocyte Epitopes on Swine Viruses: Multi-Epitope Design for Universal T Cell Vaccine

    OpenAIRE

    Liao, Yu-Chieh; Lin, Hsin-Hung; Lin, Chieh-Hua; Chung, Wen-Bin

    2013-01-01

    Classical swine fever (CSF), foot-and-mouth disease (FMD) and porcine reproductive and respiratory syndrome (PRRS) are the primary diseases affecting the pig industry globally. Vaccine induced CD8+ T cell-mediated immune response might be long-lived and cross-serotype and thus deserve further attention. Although large panels of synthetic overlapping peptides spanning the entire length of the polyproteins of a virus facilitate the detection of cytotoxic T lymphocyte (CTL) epitopes, it is an ex...

  11. Serodiagnosis of Rift Valley fever in African wildlife using a recombinant nucleocapsid-based indirect ELISA

    International Nuclear Information System (INIS)

    Antibodies to Rift Valley fever virus (RVFV) have been found in many wildlife species but their importance in the epidemiology of the disease during the inter-epidemic and epidemic periods, and including their possible specific role in the cryptic maintenance of the virus is not elucidated. A recently developed indirect ELISA (I-ELISA) based on recombinant nucleocapsid protein (rNp) of RVF virus was reported to have high analytical accuracy for the detection of IgG antibody in African buffalo sera. An indirect ELISA (I-ELISA) based on the recombinant nucleocapsid protein (rNp) of Rift Valley fever virus (RVFV) was evaluated for the detection of specific serum IgG antibody in African wildlife. Data sets derived from field-collected sera (n = 877) in Africa (antelopes = 529, black rhinoceros = 43, common zebra = 24, elephant = 73, giraffe = 81, grevy zebra = 78, warthog = 49) were categorized according to the results of a virus neutralization test. Dose response curves using different dilutions of sera known to be positive or negative in the virus neutralisation test had the expected analytical slope and the I-ELISA clearly differentiated between different levels of specific IgG antibody against RVFV in African wildlife. At cut-offs optimised by the two-graph receiver operating characteristics analysis, the diagnostic sensitivity of the I-ELISA was 100% and diagnostic specificity ranged from 99.8% to 100% while estimates for the Youden's index (J) and efficiency (Ef) ranged from 0.99 to 1 and from 99.7% to 100%, respectively. The rNp-based I-ELISA is highly accurate, safe, and offers a single assay format for rapid detection of IgG antibody to RVFV in sera of different wildlife species. This study confirm previous findings that the rNp-based I-ELISA accurately identifies sera with different concentrations of specific IgG antibodies to RVF virus, and compared to virus neutralization test it has very high diagnostic performance in various wildlife animal species. As a

  12. Innate immunity correlates with host fitness in wild boar (Sus scrofa exposed to classical swine fever.

    Directory of Open Access Journals (Sweden)

    Sophie Rossi

    Full Text Available Constitutive humoral immunity (CHI is thought to be a first-line of protection against pathogens invading vertebrate hosts. However, clear evidence that CHI correlates with host fitness in natural conditions is still lacking. This study explores the relationship between CHI, measured using a haemagglutination-haemolysis assay (HAHL, and resistance to classical swine fever virus (CSFV among wild boar piglets. The individual dynamics of HAHL during piglet growth was analysed, using 423 serum samples from 92 piglets repeatedly captured in the absence of CSFV (in 2006 within two areas showing contrasting food availability. Natural antibody levels increased with age, but, in the youngest piglets antibody levels were higher in individuals from areas with the highest food availability. Complement activity depended on natural antibody levels and piglets' body condition. In the presence of CSFV (i.e., in 2005 within one area, serum samples from piglets that were repeatedly captured were used to assess whether piglet HAHL levels affected CSFV status at a later capture. The correlation between CHI and resistance to CSFV was tested using 79 HAHL measures from 23 piglets captured during a CSFV outbreak. Both natural antibodies and complement activity levels measured at a given time correlated negatively to the subsequent probability of becoming viremic. Finally, capture-mark-recapture models showed that piglets with medium/high average complement activity, independently of their age, were significantly less at risk of becoming viremic and more likely to develop a specific immune response than piglets with low complement activity. Additionally, piglets with high average complement activity showed the highest survival prospects. This study provides evidence linking CHI to individual fitness within a natural mammal population. The results also highlight the potential of HAHL assays to explore the dynamics and co-evolution between wildlife mammal hosts and blood

  13. Detección de anticuerpos contra el virus de la peste porcina clásica mediante la prueba inmunoenzimática (CIV-ELISA y seroneutralización Detection of antibodies against the classical swine fever virus by enzime-linked immunosorbent assay (ELISA

    Directory of Open Access Journals (Sweden)

    A. ISLAS

    1997-01-01

    Full Text Available La peste porcina clásica (PPC es una enfermedad de gran importancia mundial. En Chile está sometida a un programa de control y erradi-cación. El presente ensayo tuvo como objetivo estandarizar y comparar una técnica inmunoenzimática (CIV-ELISA que detecta anticuerpos del tipo IgG dirigidos contra el virus de la PPC, con la seroneutralización (SN, técnica oficial para el diagnóstico serológico. Se utilizaron 20 cerdos híbridos Landrace x Large White de 20 kg de peso vivo, los que fueron inoculados experimentalmente con una dosis de 100.000 DICT50 del aislado virulento Quillota del virus PPC. Un grupo constituido por 4 cerdos fue vacunado 14 días antes de la inoculación. Se tomaron muestras de sangre a los 3, 6, 9, 12 y 14 días post-inoculación. Además, se obtuvieron muestras serológicas de 100 hembras reproduc-toras. Los anticuerpos anti-PPC fueron determinados por un CIV-ELISA policlonal, realizándose comparación con la prueba de SN. La prueba CIV-ELISA no detectó anticuerpos en los cerdos inoculados experimentalmente hasta los 14 días post-inoculación. Sin embargo, los cerdos vacunados previamente fueron seropositivos, situación ratificada por la SN. La sensibilidad y especificidad del CIV-ELISA fue de 90.1% y 76.4%, respectivamente. El CIV-ELISA demostró ser una prueba de fácil aplicación y los resultados son similares a los de la SNClassical swine fever (CSF is an important worldwide disease. In Chile, it is subject to a control and erradication programme. The objective of the present assay was to standardize an immunoenzimatic technique (CIV-ELISA that detects antibodies of the IgG type directed against the CSF virus and to compare it with seroneutralization. Twenty hybrid Landrace x Large White pigs with a live weight of 20 kg were used. They were experimentally inoculated with a dose of 100.000 TCID50 of the Quillota virulent isolate of the CSF virus. A four-pig group was vaccinated 14 days before inoculation

  14. Dynamics of virus shedding and antibody responses in influenza A virus-infected feral swine.

    Science.gov (United States)

    Sun, Hailiang; Cunningham, Fred L; Harris, Jillian; Xu, Yifei; Long, Li-Ping; Hanson-Dorr, Katie; Baroch, John A; Fioranelli, Paul; Lutman, Mark W; Li, Tao; Pedersen, Kerri; Schmit, Brandon S; Cooley, Jim; Lin, Xiaoxu; Jarman, Richard G; DeLiberto, Thomas J; Wan, Xiu-Feng

    2015-09-01

    Given their free-ranging habits, feral swine could serve as reservoirs or spatially dynamic 'mixing vessels' for influenza A virus (IAV). To better understand virus shedding patterns and antibody response dynamics in the context of IAV surveillance amongst feral swine, we used IAV of feral swine origin to perform infection experiments. The virus was highly infectious and transmissible in feral swine, and virus shedding patterns and antibody response dynamics were similar to those in domestic swine. In the virus-inoculated and sentinel groups, virus shedding lasted ≤ 6 and ≤ 9 days, respectively. Antibody titres in inoculated swine peaked at 1 : 840 on day 11 post-inoculation (p.i.), remained there until 21 days p.i. and dropped to nucleoprotein position 473. Using data from cell culture as a benchmark, sensitivity and specificity of a matrix gene-based quantitative reverse transcription-PCR method using nasal swab samples for detection of IAV in feral swine were 78.9 and 78.1 %, respectively. Using data from haemagglutination inhibition assays as a benchmark, sensitivity and specificity of an ELISA for detection of IAV-specific antibody were 95.4 and 95.0 %, respectively. Serological surveillance from 2009 to 2014 showed that ∼7.58 % of feral swine in the USA were positive for IAV. Our findings confirm the susceptibility of IAV infection and the high transmission ability of IAV amongst feral swine, and also suggest the need for continued surveillance of IAVs in feral swine populations. PMID:26297148

  15. Emergence of European Avian Influenza Virus-Like H1N1 Swine Influenza A Viruses in China▿

    OpenAIRE

    Liu, Jinhua; Bi, Yuhai; Qin, Kun; Fu, Guanghua; Yang, Jun; Peng, Jinshan; Ma, Guangpeng; Liu, Qinfang; Pu, Juan; Tian, Fulin

    2009-01-01

    During swine influenza surveillance from 2007 to 2008, 10 H1N1 viruses were isolated and analyzed for their antigenic and phylogenetic properties. Our study revealed the emergence of avian-origin European H1N1 swine influenza virus in China, which highlights the necessity of swine influenza surveillance for potential pandemic preparedness.

  16. Enhanced Pneumonia With Pandemic 2009 A/H1N1 Swine Influenza Virus in Pigs

    Science.gov (United States)

    Introduction. Swine influenza A viruses (SIV) in the major swine producing regions of North America consist of multiple subtypes of endemic H1N1, H1N2, and H3N2 derived from swine, avian and human influenza viruses with a triple reassortant internal gene (TRIG) constellation (1). Genetic drift and r...

  17. Dengue Virus Tropism in Humanized Mice Recapitulates Human Dengue Fever

    OpenAIRE

    Javier Mota; Rebeca Rico-Hesse

    2011-01-01

    Animal models of dengue virus disease have been very difficult to develop because of the virus' specificity for infection and replication in certain human cells. We developed a model of dengue fever in immunodeficient mice transplanted with human stem cells from umbilical cord blood. These mice show measurable signs of dengue disease as in humans (fever, viremia, erythema and thrombocytopenia), and after infection with the most virulent strain of dengue serotype 2, humanized mice showed infec...

  18. Identification of cytotoxic T lymphocyte epitopes on swine viruses: multi-epitope design for universal T cell vaccine.

    Directory of Open Access Journals (Sweden)

    Yu-Chieh Liao

    Full Text Available Classical swine fever (CSF, foot-and-mouth disease (FMD and porcine reproductive and respiratory syndrome (PRRS are the primary diseases affecting the pig industry globally. Vaccine induced CD8(+ T cell-mediated immune response might be long-lived and cross-serotype and thus deserve further attention. Although large panels of synthetic overlapping peptides spanning the entire length of the polyproteins of a virus facilitate the detection of cytotoxic T lymphocyte (CTL epitopes, it is an exceedingly costly and cumbersome approach. Alternatively, computational predictions have been proven to be of satisfactory accuracy and are easily performed. Such a method enables the systematic identification of genome-wide CTL epitopes by incorporating epitope prediction tools in analyzing large numbers of viral sequences. In this study, we have implemented an integrated bioinformatics pipeline for the identification of CTL epitopes of swine viruses including the CSF virus (CSFV, FMD virus (FMDV and PRRS virus (PRRSV and assembled these epitopes on a web resource to facilitate vaccine design. Identification of epitopes for cross protections to different subtypes of virus are also reported in this study and may be useful for the development of a universal vaccine against such viral infections among the swine population. The CTL epitopes identified in this study have been evaluated in silico and possibly provide more and wider protection in compared to traditional single-reference vaccine design. The web resource is free and open to all users through http://sb.nhri.org.tw/ICES.

  19. Swine Influenza Viruses – Evolution and Zoonotic Potential

    DEFF Research Database (Denmark)

    Fobian, Kristina

    Influenza A virus (IAV) is an important respiratory pathogen with a broad host range. The natural reservoir for IAV is waterfowls, but both human and swine are considered natural hosts. During the past century IAV has caused severe pandemics as well as seasonal epidemics in the human population. In...... mixing vessels of new IAVs. Furthermore, transmission of IAVs from swine to human and vice versa has been documented on several occasions and further classifies this virus as a highly important zoonosis. This aspect enhances the possibility of the formation and establishment of new and potentially more...... virulent viruses with the capacity to cause severe pandemics. Therefore, it is important to gain a deeper understanding of the evolution of SIVs, their zoonotic potential as well as host-range characteristics and this PhD project aimed at elucidating parts of these important points. The PhD thesis begins...

  20. Swine Influenza Viruses: a North American Perspective

    Science.gov (United States)

    Influenza is a zoonotic viral disease that represents a health and economic threat to both humans and animals worldwide. Swine influenza was first recognized clinically in pigs in the Midwestern U.S. in 1918, coinciding with the human influenza pandemic known as the Spanish flu. Since that time swin...

  1. Marburg Hemorrhagic Fever (Marburg HF)

    Science.gov (United States)

    ... host of Marburg virus is the African fruit bat, Rousettus aegyptiacus . Fruit bats infected with Marburg virus do not to show ... Information for Specific Groups, References... Marburg HF Outbreak Distribution Map Factsheet: Marburg Hemorrhagic Fever [PDF - 3 pages] ...

  2. 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

    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...

  3. Advancese in Classical swine fever and status of China's traditional vaccines.%猪瘟疫苗研究进展及我国传统疫苗的研究现状

    Institute of Scientific and Technical Information of China (English)

    杜军; 舒常永; 张剑扬

    2009-01-01

    @@ 猪瘟是由猪瘟病毒(Classical swine fever virus,CSFV)引起的一种高度接触性传染病,也是世界粮农组织和各国政府密切关注的主要传染病之一,OIE国际委员会(2002版)中,猪瘟被列为A类15种法定传染病之一.

  4. Quantitative Real-Time PCR Detection of Rift Valley Fever Virus and Its Application to Evaluation of Antiviral Compounds

    OpenAIRE

    Garcia, Stephan; Crance, Jean Marc; Billecocq, Agnes; Peinnequin, Andre; Jouan, Alain; Bouloy, Michele; Garin, Daniel

    2001-01-01

    The Rift Valley fever virus (RVFV), a member of the genus Phlebovirus (family Bunyaviridae) is an enveloped negative-strand RNA virus with a tripartite genome. Until 2000, RVFV circulation was limited to the African continent, but the recent deadly outbreak in the Arabian Peninsula dramatically illustrated the need for rapid diagnostic methods, effective treatments, and prophylaxis. A method for quantifying the small RNA segment by a real-time detection reverse transcription (RT)-PCR using Ta...

  5. [Diagnostic image (157). A man with fever and a 'tache noire' after a holiday in South Africa. Rickettsiosis, probably African tick-bite fever].

    Science.gov (United States)

    Diederen, B M; Buiting, A G

    2003-09-20

    A 54-year-old man presented with fever and an eschar, probably caused by African tick-bite fever, contracted during a holiday in South Africa. He recovered rapidly after treatment with doxycyclin. PMID:14533497

  6. 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

    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....

  7. Demonstrating freedom from disease using multiple complex data sources 2: Case study-Classical swine fever in Denmark

    DEFF Research Database (Denmark)

    Martin, P.A.J.; Cameron, A.R.; Barfod, Kristen;

    2007-01-01

    A method for quantitative evaluation of surveillance for disease freedom has been presented in the accompanying paper (Martin et al., 2007). This paper presents an application of the methods, using as an example surveillance for classical swine fever (CSF) in Denmark in 2005. A scenario tree model...

  8. 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...

  9. A Recombinant Vesicular Stomatitis Virus-Based Lassa Fever Vaccine Protects Guinea Pigs and Macaques against Challenge with Geographically and Genetically Distinct Lassa Viruses

    OpenAIRE

    David Safronetz; Chad Mire; Kyle Rosenke; Friederike Feldmann; Elaine Haddock; Thomas Geisbert; Heinz Feldmann

    2015-01-01

    Background Lassa virus (LASV) is endemic in several West African countries and is the etiological agent of Lassa fever. Despite the high annual incidence and significant morbidity and mortality rates, currently there are no approved vaccines to prevent infection or disease in humans. Genetically, LASV demonstrates a high degree of diversity that correlates with geographic distribution. The genetic heterogeneity observed between geographically distinct viruses raises concerns over the potentia...

  10. Immunoglobulins in pigs vaccinated with a subunit E2 and an attenuated c strain vaccine against classical swine fever

    Directory of Open Access Journals (Sweden)

    Terzić Svjetlana

    2009-01-01

    Full Text Available The aim of this study was to detect changes in the concentration of serum immunoglobulins following vaccination against classical swine fever (CSF with an attenuated C strain and a subunit E2 vaccine. Furthermore, the adjuvanticity of an attenuated parapoxvirus ORF virus for the subunit vaccine against CSF was evaluated. Peripheral blood samples were collected before the vaccination and at post-vaccination days 4, 10, 21 and 28. The samples were assessed by a colorimetric method for the detection of total proteins, as well as albumin, IgA and IgM levels and by radial immunodiffusion to record the IgG level. Our findings are in accordance with the normal concentrations of porcine IgG, IgA and IgM. However, a significant increase of some immunoglobulin classes was recorded. The increase of the IgM level in vaccinated pigs confirmed an early development of humoral immunity. Interestingly, the subunit E2 vaccine induced the increase of IgM earlier then did the attenuated C strain. Since the IgG concentration was not significantly increased we assumed that the period of 28 days following vaccination was too short to detect any changes in the IgG level, thus reflecting a late humoral immune response. Although, IgA antibodies are mostly responsible for humoral immunity at the mucosal surfaces, in our experiment the attenuated C strain induced a significantly higher production of this immunoglobulin class in the serum very early (on day 4 following vaccination. This could be ascribed to the affinity of IgA antibodies to neutralize or agglutinate virus particles. Early appearance (4 and 10 days after the vaccination of a significantly higher concentration of IgG and IgM could be induced by the ORF virus strain D1701 applied as an adjuvant.

  11. 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

    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...... genes from the pandemic H1N1 virus. This study contribute significantly to our knowledge of the epidemiology of swine influenza A virus circulating in Danish swine and the potential role of swine in the emergence of novel reassortant viruses.......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...

  12. It is not just AIV: From avian to swine-origin influenza virus

    Institute of Scientific and Technical Information of China (English)

    GAO George F; SUN YePing

    2010-01-01

    @@ In March and early April 2009, a new swine-origin influenza A (H1N1) virus (S-OIV) emerged in Mexico and the United States.The virus spreads worldwide by human-to-human transmission.Within a few weeks, it reached a pandemic level.The virus is a novel reassorment virus.It contains gene fragments of influenza virus of swine, avian and human emerged from a triple reassortant virus circulating in North American swine.The source triple-reassortant itself comprised genes derived from avian (PB2 and PA), human H3N2 (PB1) and classical swine (HA, NP and NS) lineages.In contrast, the NA and M gene segments have their origin in the Eurasian avian-like swine H1N1 lineage (Figure 1).

  13. 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

    pigs from 6 to 11 weeks of age were inoculated with CSFV-Lithuania, CSFV-Eystrup, CSFV-Glentorf and CSFV-Romania, respectively. All pigs were closely monitored and clinical scoring (CS) as well as body temperature (BT) recording was performed on a daily basis. Blood sample collection was performed on...... demonstrated that it remains a particular challenge to provide a competent diagnostic tool box for low virulent strains of CSFV, e.g. CSFV-Glentorf. Acknowledgements: The authors wish to thank the EU Reference laboratory for Classical Swine Fever, TIHO, Hannover, for kindly supplying the CSFV-Romania, the CSFV......-Glentorf and the CSFV-Lithuania strains to our Institute. A special thank to NRL-Romania and NRL-Lithuania for supplying the CSFV-Romania and CSFV-Lithuania strains, respectively, to the EU Reference laboratory. This study was financially supported by Directorate for Food, Fisheries and Agri Business in...

  14. Efficacy of Inactivated Swine Influenza Virus Vaccines Against 2009 H1N1 Influenza Virus in Pigs

    Science.gov (United States)

    Introduction. The gene constellation of the 2009 pandemic H1N1 virus is a unique combination from swine influenza A viruses (SIV) of North American and Eurasian lineages, but prior to April 2009 had never before been identified in swine or other species (1). Although its hemagglutinin gene is relat...

  15. Yellow Fever Outbreak, Southern Sudan, 2003

    OpenAIRE

    Onyango, Clayton O.; Grobbelaar, Antoinette A.; Gibson, Georgina V.F.; Sang, Rosemary C.; Sow, Abdourahmane; Swanepoel, Robert; Burt, Felicity J.

    2004-01-01

    In May 2003, an outbreak of fatal hemorrhagic fever, caused by yellow fever virus, occurred in southern Sudan. Phylogenetic analysis showed that the virus belonged to the East African genotype, which supports the contention that yellow fever is endemic in East Africa with the potential to cause large outbreaks in humans.

  16. 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

  17. Yellow Fever Virus Infectivity for Bolivian Aedes aegypti Mosquitoes

    OpenAIRE

    Mutebi, John-Paul; Gianella, Alberto; Travassos da Rosa, Amelia; Tesh, Robert B; Barrett, Alan D. T.; Higgs, Stephen

    2004-01-01

    The absence of urban yellow fever virus (YFV) in Bolivian cities has been attributed to the lack of competent urban mosquito vectors. Experiments with Aedes aegypti from Santa Cruz, Bolivia, demonstrated infection (100%), dissemination (20%), and transmission of a Bolivian YFV strain (CENETROP-322).

  18. Complete Genome Sequence of Rift Valley Fever Virus Strain Lunyo

    OpenAIRE

    Lumley, Sarah; Horton, Daniel L.; Marston, Denise A.; Johnson, Nicholas; Ellis, Richard J.; Fooks, Anthony R.; Hewson, Roger

    2016-01-01

    Using next-generation sequencing technologies, the first complete genome sequence of Rift Valley fever virus strain Lunyo is reported here. Originally reported as an attenuated antigenic variant strain from Uganda, genomic sequence analysis shows that Lunyo clusters together with other Ugandan isolates.

  19. First case of imported African tick-bite fever in Poland - Case report.

    Science.gov (United States)

    Tomasiewicz, Krzysztof; Krzowska-Firych, Joanna; Bielec, Dariusz; Socolovschi, Cristina; Raoult, Didier

    2015-01-01

    This is the first report of a case of African tick bite fever (ATBF) imported to Poland from South-Africa. The patient presented with fever of 38.4(o)C, generalized maculopapular rash and single eschar. Diagnosis was confirmed by polymerase chain reaction (PCR) from eschar biopsies. The patient recovered without any sequelae after 7 days treatment with doxycycline. PMID:26403104

  20. First case of imported African tick-bite fever in Poland – Case report

    OpenAIRE

    Krzysztof Tomasiewicz; Joanna Krzowska-Firych; Dariusz Bielec; Cristina Socolovschi; Didier Raoult

    2015-01-01

    This is the first report of a case of African tick bite fever (ATBF) imported to Poland from South-Africa. The patient presented with fever of 38.4[sup]o[/sup]C, generalized maculopapular rash and single eschar. Diagnosis was confirmed by polymerase chain reaction (PCR) from eschar biopsies. The patient recovered without any sequelae after 7 days treatment with doxycycline.

  1. Emergence of a novel swine-origin influenza A virus (S-OIV) H1N1 virus in humans

    Science.gov (United States)

    Peiris, JS Malik; Poon, Leo LM; Guan, Yi

    2016-01-01

    A recently emerged novel influenza A H1N1 virus continues to spread globally. The virus contains a novel constellation of gene segments, the nearest known precursors being viruses found in swine and it likely arose through reassortment of two or more viruses of swine origin. H1N1, H1N2 and H3N2 subtype swine influenza viruses have occasionally infected humans before but such zoonotic transmission-events did not lead to sustained human-to-human transmission in the manner this swine-origin influenza virus (S-OIV) has done. Its transmission among humans appears to be higher than that observed with seasonal influenza. Children and young adults appear to those most affected and also those who appear to maintain transmission. Clinical disease generally appears mild but complications leading to hospitalization can occur, especially in those with underlying lung or cardiac disease, diabetes or those on immunosuppresive therapies. There are concerns that the virus may reassort with existing human influenza virus giving rise to more transmissible or more pathogenic viruses. The virus appears to retain the potential to transmit back to swine and thus continued reassortment with swine viruses is a cause for concern. PMID:19540800

  2. 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.

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

    International Nuclear Information System (INIS)

    The virucidal effect of 60Co 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)

  4. 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...... reported such contact (P<0.001). Most of the affected miners (94 percent) worked in an underground mine. Cessation of the outbreak coincided with flooding of the mine. Epidemiologic evidence of multiple introductions of infection into the population was substantiated by the detection of at least nine...... imply that reservoir hosts of Marburg virus inhabit caves, mines, or similar habitats....

  5. Rapid Detection and Quantification of RNA of Ebola and Marburg Viruses, Lassa Virus, Crimean-Congo Hemorrhagic Fever Virus, Rift Valley Fever Virus, Dengue Virus, and Yellow Fever Virus by Real-Time Reverse Transcription-PCR

    Science.gov (United States)

    Drosten, Christian; Göttig, Stephan; Schilling, Stefan; Asper, Marcel; Panning, Marcus; Schmitz, Herbert; Günther, Stephan

    2002-01-01

    Viral hemorrhagic fevers (VHFs) are acute infections with high case fatality rates. Important VHF agents are Ebola and Marburg viruses (MBGV/EBOV), Lassa virus (LASV), Crimean-Congo hemorrhagic fever virus (CCHFV), Rift Valley fever virus (RVFV), dengue virus (DENV), and yellow fever virus (YFV). VHFs are clinically difficult to diagnose and to distinguish; a rapid and reliable laboratory diagnosis is required in suspected cases. We have established six one-step, real-time reverse transcription-PCR assays for these pathogens based on the Superscript reverse transcriptase-Platinum Taq polymerase enzyme mixture. Novel primers and/or 5′-nuclease detection probes were designed for RVFV, DENV, YFV, and CCHFV by using the latest DNA database entries. PCR products were detected in real time on a LightCycler instrument by using 5′-nuclease technology (RVFV, DENV, and YFV) or SybrGreen dye intercalation (MBGV/EBOV, LASV, and CCHFV). The inhibitory effect of SybrGreen on reverse transcription was overcome by initial immobilization of the dye in the reaction capillaries. Universal cycling conditions for SybrGreen and 5′-nuclease probe detection were established. Thus, up to three assays could be performed in parallel, facilitating rapid testing for several pathogens. All assays were thoroughly optimized and validated in terms of analytical sensitivity by using in vitro-transcribed RNA. The ≥95% detection limits as determined by probit regression analysis ranged from 1,545 to 2,835 viral genome equivalents/ml of serum (8.6 to 16 RNA copies per assay). The suitability of the assays was exemplified by detection and quantification of viral RNA in serum samples of VHF patients. PMID:12089242

  6. The risk of Rift Valley fever virus introduction and establishment in the United States and European Union

    OpenAIRE

    Rolin, Alicia I.; Berrang-Ford, Lea; Kulkarni, Manisha A

    2013-01-01

    Rift Valley fever virus (RVFV) is an arthropod-borne disease resulting in severe morbidity and mortality in both human and ruminant populations. First identified in Kenya in 1930, the geographical range of RVFV has been largely constrained to the African continent, yet has recently spread to new regions, and is identified as a priority disease with potential for geographic emergence. We present a systematic literature review assessing the potential for RVFV introduction and establishment in t...

  7. Advances in research on clinic and epidemiology of swine fever%猪瘟的临床与流行病学研究进展

    Institute of Scientific and Technical Information of China (English)

    吕宗吉; 涂长春; 余兴龙

    2001-01-01

    @@猪瘟(Hog cholera,HC 或Classical Swine Fever,CSF)是对养猪业威胁最大的烈性传染病[1,2],我国每年因猪瘟死亡的猪占病死猪的1/3以上;1993年后,一些已宣布消灭了猪瘟的国家和地区,如荷兰、瑞士、比利时、瑞典、德国、西班牙、英国等,又先后出现了猪瘟的复发。然而由于各种原因,自20世纪60年代以来,猪瘟在临床与流行病学特点上均已发生了很大的变化,而且这种变化是世界性的,并不局限于一时一地。此外,迄今为止虽然猪瘟病毒(Classical Swine Fever Virus,CSFV;或Hog Cholera Virus,HCV)还只有一个血清型,但用单克隆抗体(MAb)可以将CSFV区分为不同的毒株,而应用基因分析方法可将CSFV分为2个基因群5个亚群。

  8. Entomological profile of yellow fever epidemics in the Central African Republic, 2006–2010

    Directory of Open Access Journals (Sweden)

    Ngoagouni Carine

    2012-08-01

    Full Text Available Abstract Background The causative agent of yellow fever is an arbovirus of the Flaviviridae family transmitted by infected Aedes mosquitoes, particularly in Africa. In the Central African Republic since 2006, cases have been notified in the provinces of Ombella-Mpoko, Ouham-Pende, Basse-Kotto, Haute-Kotto and in Bangui the capital. As the presence of a vector of yellow fever virus (YFV represents a risk for spread of the disease, we undertook entomological investigations at these sites to identify potential vectors of YFV and their abundance. Findings Between 2006 and 2010, 5066 mosquitoes belonging to six genera and 43 species were identified. The 20 species of the Aedes genus identified included Ae. aegypti, the main vector of YFV in urban settings, and species found in tropical forests, such as Ae. africanus, Ae. simpsoni, Ae. luteocephalus, Ae. vittatus and Ae. opok. These species were not distributed uniformly in the various sites studied. Thus, the predominant Aedes species was Ae. aegypti in Bangui (90.7 % and Basse-Kotto (42.2 %, Ae. africanus in Ombella-Mpoko (67.4 % and Haute-Kotto (77.8 % and Ae. vittatus in Ouham-Pende (62.2 %. Ae. albopictus was also found in Bangui. The distribution of these dominant species differed significantly according to study site (P Aedes mosquitoes analysed by polymerase chain reaction contained the YFV genome. Conclusion The results indicate a wide diversity of vector species for YFV in the Central African Republic. The establishment of surveillance and vector control programs should take into account the ecological specificity of each species.

  9. Porcine epidemic diarrhea virus: An emerging and re-emerging epizootic swine virus

    OpenAIRE

    Lee, Changhee

    2015-01-01

    The enteric disease of swine recognized in the early 1970s in Europe was initially described as “epidemic viral diarrhea” and is now termed “porcine epidemic diarrhea (PED)”. The coronavirus referred to as PED virus (PEDV) was determined to be the etiologic agent of this disease in the late 1970s. Since then the disease has been reported in Europe and Asia, but the most severe outbreaks have occurred predominantly in Asian swine-producing countries. Most recently, PED first emerged in early 2...

  10. Lymphocytic choriomeningitis virus (LCMV) infection of macaques: a model for Lassa fever

    OpenAIRE

    Zapata, Juan C.; Pauza, C. David; Djavani, Mahmoud M.; Rodas, Juan D.; Moshkoff, Dmitry; Bryant, Joseph; Ateh, Eugene; Garcia, Cybele; Lukashevich, Igor S.; Salvato, Maria S.

    2011-01-01

    Arenaviruses such as Lassa fever virus (LASV) and lymphocytic choriomeningitis virus (LCMV) are benign in their natural reservoir hosts, and can occasionally cause severe viral hemorrhagic fever (VHF) in non-human primates and in human beings. LCMV is considerably more benign for human beings than Lassa virus, however certain strains, like the LCMV-WE strain, can cause severe disease when the virus is delivered as a high-dose inoculum. Here we describe a rhesus macaque model for Lassa fever t...

  11. Genetic and experimental evidence for cross-species infection by swine hepatitis E virus.

    Science.gov (United States)

    Meng, X J; Halbur, P G; Shapiro, M S; Govindarajan, S; Bruna, J D; Mushahwar, I K; Purcell, R H; Emerson, S U

    1998-12-01

    Prior to the recent discovery of the swine hepatitis E virus (swine HEV) in pigs from the midwestern United States, HEV was not considered endemic to this country. Since swine HEV is antigenically and genetically related to human strains of HEV, it was important to characterize this new virus further. The infectivity titer of a pool of swine HEV in pigs was determined in order to prepare a standardized reagent and to evaluate the dose response in pigs. Although the sequence of swine HEV varied extensively from those of most human strains of HEV, it was very closely related to the two strains of human HEV (US-1 and US-2) isolated in the United States. The U.S. strains which were recently recovered from two patients with clinical hepatitis E in the United States shared >/=97% amino acid identity with swine HEV in open reading frames 1 and 2. Phylogenetic analyses of different regions of the genome revealed that swine HEV and the U.S. strains grouped together and formed a distinct branch. These results suggested that swine HEV may infect humans. When we inoculated rhesus monkeys and a chimpanzee, experimental surrogates of humans, with swine HEV, the primates became infected. Furthermore, in a reciprocal experiment, specific-pathogen-free pigs were experimentally infected with the US-2 strain of human HEV that is genetically similar to swine HEV. These results provided experimental evidence for cross-species infection by the swine virus. Thus, humans appear to be at risk of infection with swine HEV or closely related viruses. PMID:9811705

  12. Nucleotide sequence variation of the envelope protein gene identifies two distinct genotypes of yellow fever virus.

    OpenAIRE

    Chang, G J; Cropp, B. C.; Kinney, R M; Trent, D W; Gubler, D. J.

    1995-01-01

    The evolution of yellow fever virus over 67 years was investigated by comparing the nucleotide sequences of the envelope (E) protein genes of 20 viruses isolated in Africa, the Caribbean, and South America. Uniformly weighted parsimony algorithm analysis defined two major evolutionary yellow fever virus lineages designated E genotypes I and II. E genotype I contained viruses isolated from East and Central Africa. E genotype II viruses were divided into two sublineages: IIA viruses from West A...

  13. Complete Genome Sequence of a Novel Avian-Like H3N2 Swine Influenza Virus Discovered in Southern China

    OpenAIRE

    Su, Shuo; Chen, Ji-dang; Qi, Hai-tao; Zhu, Wan-jun; Xie, Jie-xiong; Huang, Zhen; Tan, Li-kai; Qi, Wen-bao; Zhang, Gui-hong

    2012-01-01

    We report here the complete genomic sequence of a novel avian-like H3N2 swine influenza virus containing an H5N1 highly pathogenic avian influenza virus segment that was obtained from swine in southern China. Phylogenetic analysis indicated that this virus might originate from domestic aquatic birds. The sequence information provided herein suggests that continuing study is required to determine if this virus can be established in the swine population and pose potential threats to public health.

  14. Early Induction of Cytokines in Pigs Coinfected with Swine Influenza Virus and Bordetella bronchiseptica

    Science.gov (United States)

    Respiratory disease is one of the most important health issues for the swine industry, and coinfection with two or more pathogens is a common occurrence. Bordetella bronchiseptica and swine influenza virus (SIV) are important and common respiratory pathogens of pigs. The effect of coinfection of S...

  15. Efficacy of intranasal administration of a truncated NS1 modified live influenza virus vaccine in swine

    Science.gov (United States)

    In the U.S., despite available swine influenza virus (SIV) vaccines, multiple influenza subtypes as well as antigenic and genetic variants within subtypes continue to circulate in the swine population. One of the challenges to control and eliminate SIV is that the currently used inactivated influenz...

  16. Meat juice as diagnostic sample for virological and serological diagnosis of classical swine fever.

    Science.gov (United States)

    Kaden, Volker; Lange, Elke; Nagel-Kohl, Uschi; Bruer, Wilhelm

    2009-05-01

    The objective of this paper was to assess if meat juice is a suitable substrate for virological and serological diagnosis of classical swine fever (CSF). Fifty-six domestic pigs and 21 wild boars experimentally vaccinated and/or infected as well as 129 field samples from wild boars were involved in this study. Meat juice from diaphragm, forequarter and hindquarter was used for investigations. CSFV and viral RNA were detected in meat juice between days 5 and 21 post infection (pi). Animals which had survived the infection were diagnosed virologically negative and antibody-positive in muscle fluid. After vaccination or vaccination and subsequent infection of animals (n = 42), meat juice samples scored serologically positive. The antibody titres of these samples were significantly lower than in serum. Serological investigations of field samples derived from wild boars (n = 75) shot in Mecklenburg-Western Pomerania showed a clear correlation between the antibody-positive samples in serum and in meat juice, whereas the serological results of meat juice samples (n = 54) from wild boars collected in Lower Saxony were slightly different. The reasons for these differences are discussed. Nevertheless, meat juice seems to be a suitable substrate for CSF diagnosis, especially for wild boars. PMID:19462640

  17. Prospects of improved classical swine fever control in backyard pigs through oral vaccination.

    Science.gov (United States)

    Dietze, Klaas; Milicevic, Vesna; Depner, Klaus

    2013-01-01

    Success in controlling classical swine fever (CSF) in regions with high proportions of pigs kept in small scale and low-biosecurity production systems, often referred to as backyard production, tends to be hampered by the lack of control strategies properly addressing the peculiarities of this epidemiologically important subpopulation. Under many circumstances the commonly practiced parenteral immunisation using live attenuated C-strain vaccine shows limitations concerning outreach of services and overall vaccination coverage in the backyard pig population. It is therefore proposed to stronger consider oral vaccine baits, as used for CSF control in wild boar, to complement the set of tools for CSF control in domestic pigs. First field results confirm the feasibility of its practical implementation. Next to the increased flexibility in the delivery to the end user, this non-invasive method comes along with the advantage of reducing the need for direct animal contact and biosecurity-relevant interventions that might cause the spread of diseases through vaccination campaigns entailing external personnel entering farm premises. In combination with epidemiological methods suitable for this production sector like e.g. participatory epidemiology, adapted CSF control strategies can better support the needs of small scale farmers and ultimately contribute to household food security for a large number of stakeholders that will have backyard pig production as a reality for decades to come. PMID:24511822

  18. A recombinant nucleocapsid-based indirect ELISA for serodiagnosis of Rift Valley fever in African wildlife

    International Nuclear Information System (INIS)

    An indirect ELISA (I-ELISA) based on the recombinant nucleocapsid protein (rNp) of Rift Valley fever virus (RVFV) was evaluated for the detection of specific serum IgG antibody in African wildlife. Data sets derived from field-collected sera (n = 918) in Africa (antelopes = 570, black rhinoceros = 43, common zebra = 24, elephant = 73, giraffe = 81, grevy zebra = 78, warthog = 49) were categorised according to the results of a virus neutralisation test (VNT). At cut-offs optimised by the two-graph receiver operating characteristics analysis, the diagnostic sensitivity of the I-ELISA was 100% and diagnostic specificity ranged from 99.8% to 100% while estimates for the Youden's index (J) and efficiency (Ef) ranged from 0.99 to 1 and from 99.7% to 100%, respectively. The rNp-based I-ELISA is highly accurate, safe, and offers a single assay format for rapid detection of IgG antibody to RVFV in sera of different wildlife species. (author)

  19. 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.,...

  20. 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.

  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;

    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......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...... were isolated in MDCK cells, RNA extracted and the hemagglutinin and neuraminidase genes full length sequenced. In addition, the isolates were tested in hemagglutination inhibition (HI) tests against a panel of known antisera raised against a range of European swine influenza virus isolates...

  2. 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.

  3. Single-cycle replicable Rift Valley fever virus mutants as safe vaccine candidates.

    Science.gov (United States)

    Terasaki, Kaori; Tercero, Breanna R; Makino, Shinji

    2016-05-01

    Rift Valley fever virus (RVFV) is an arbovirus circulating between ruminants and mosquitoes to maintain its enzootic cycle. Humans are infected with RVFV through mosquito bites or direct contact with materials of infected animals. The virus causes Rift Valley fever (RVF), which was first recognized in the Great Rift Valley of Kenya in 1931. RVF is characterized by a febrile illness resulting in a high rate of abortions in ruminants and an acute febrile illness, followed by fatal hemorrhagic fever and encephalitis in humans. Initially, the virus was restricted to the eastern region of Africa, but the disease has now spread to southern and western Africa, as well as outside of the African continent, e.g., Madagascar, Saudi Arabia and Yemen. There is a serious concern that the virus may spread to other areas, such as North America and Europe. As vaccination is an effective tool to control RVFV epidemics, formalin-inactivated vaccines and live-attenuated RVFV vaccines have been used in endemic areas. The formalin-inactivated vaccines require boosters for effective protection, whereas the live-attenuated vaccines enable the induction of protective immunity by a single vaccination. However, the use of live-attenuated RVFV vaccines for large human populations having a varied health status is of concern, because of these vaccines' residual neuro-invasiveness and neurovirulence. Recently, novel vaccine candidates have been developed using replication-defective RVFV that can undergo only a single round of replication in infected cells. The single-cycle replicable RVFV does not cause systemic infection in immunized hosts, but enables the conferring of protective immunity. This review summarizes the properties of various RVFV vaccines and recent progress on the development of the single-cycle replicable RVFV vaccines. PMID:26022573

  4. First case of imported African tick-bite fever in Poland – Case report

    Directory of Open Access Journals (Sweden)

    Krzysztof Tomasiewicz

    2015-09-01

    Full Text Available This is the first report of a case of African tick bite fever (ATBF imported to Poland from South-Africa. The patient presented with fever of 38.4[sup]o[/sup]C, generalized maculopapular rash and single eschar. Diagnosis was confirmed by polymerase chain reaction (PCR from eschar biopsies. The patient recovered without any sequelae after 7 days treatment with doxycycline.

  5. Expression of the classical swine fever E2 recombinant protein and examination of DNA-vaccine based on one subunit

    International Nuclear Information System (INIS)

    Full text: The aim of the work was to study the possibility of using the Classical Swine Fever Virus (CSFV) E2 (gp51-C55) recombinant protein expressed in E.coli in an immunologically active form and the creation of a DNA-vaccine model based on the gene. For minimizing the refolding problems of the recombinant protein one of two subunits of CSFV E2protein was chosen for production. This subunit has the domains A and D with the conservative epitopes some of which, in the domain A, induce synthesis of virus neutralizing antibodies. Viral RNA was isolated from the CSFV virulent strain Shi-Min, which was produced in a continuous swine kidney PK-15 cell culture (passage 37) Oligonucleotide primers were designed based on the Brescia (GeneBank, M31768) strain sequence Sn 2647-C2668 and Asn 3492-C3471. For additional RT-PCR controls the obtained fragment (846 n. p.) from isolates from CSF outbreak in Ukraine in 1994. It was shown that only the samples from the acute form of disease, wherever the amplicon sizes corresponded to the Shi-Min fragment, readily hybridized under this in stringency conditions. The subsequent sequence analysis of the fragment and the phylogenetic analyses with the use of sequences of various origin strains and isolates, placed the virus in group 1, subgroup 1.1, according to the classification suggested by D. Paton in 1995. For protein synthesis 3 constructions for plasmids expressing with the insert of CSFV E2 gene were created: CSFV-pET24a (+) -C as the individual form of the protein with the molecular mass (m.m.) 34 kD; CSFV-pGEX-2T - as fused with glutathion-S-tsansphesase, m.m. 59 kD and CSFV-pLY -C as fused with one subunit of γ-galactisidase, m.m. 107 kD. All 3 variants of the protein were synthesized as inclusion bodies with an expression level of 15-C20%. After optimizing the purification and refolding conditions, antigenic properties of the proteins were characterized in an indirect ELISA and immunoperoxidase test with homologous and

  6. Interspecies interactions and potential Influenza A virus risk in small swine farms in Peru

    Directory of Open Access Journals (Sweden)

    McCune Sarah

    2012-03-01

    Full Text Available Abstract Background The recent avian influenza epidemic in Asia and the H1N1 pandemic demonstrated that influenza A viruses pose a threat to global public health. The animal origins of the viruses confirmed the potential for interspecies transmission. Swine are hypothesized to be prime "mixing vessels" due to the dual receptivity of their trachea to human and avian strains. Additionally, avian and human influenza viruses have previously been isolated in swine. Therefore, understanding interspecies contact on smallholder swine farms and its potential role in the transmission of pathogens such as influenza virus is very important. Methods This qualitative study aimed to determine swine-associated interspecies contacts in two coastal areas of Peru. Direct observations were conducted at both small-scale confined and low-investment swine farms (n = 36 and in open areas where swine freely range during the day (n = 4. Interviews were also conducted with key stakeholders in swine farming. Results In both locations, the intermingling of swine and domestic birds was common. An unexpected contact with avian species was that swine were fed poultry mortality in 6/20 of the farms in Chancay. Human-swine contacts were common, with a higher frequency on the confined farms. Mixed farming of swine with chickens or ducks was observed in 36% of all farms. Human-avian interactions were less frequent overall. Use of adequate biosecurity and hygiene practices by farmers was suboptimal at both locations. Conclusions Close human-animal interaction, frequent interspecies contacts and suboptimal biosecurity and hygiene practices pose significant risks of interspecies influenza virus transmission. Farmers in small-scale swine production systems constitute a high-risk population and need to be recognized as key in preventing interspecies pathogen transfer. A two-pronged prevention approach, which offers educational activities for swine farmers about sound hygiene and

  7. A recombinant vesicular stomatitis virus-based Lassa fever vaccine protects guinea pigs and macaques against challenge with geographically and genetically distinct Lassa viruses.

    Directory of Open Access Journals (Sweden)

    David Safronetz

    2015-04-01

    Full Text Available Lassa virus (LASV is endemic in several West African countries and is the etiological agent of Lassa fever. Despite the high annual incidence and significant morbidity and mortality rates, currently there are no approved vaccines to prevent infection or disease in humans. Genetically, LASV demonstrates a high degree of diversity that correlates with geographic distribution. The genetic heterogeneity observed between geographically distinct viruses raises concerns over the potential efficacy of a "universal" LASV vaccine. To date, several experimental LASV vaccines have been developed; however, few have been evaluated against challenge with various genetically unique Lassa virus isolates in relevant animal models.Here we demonstrate that a single, prophylactic immunization with a recombinant vesicular stomatitis virus (VSV expressing the glycoproteins of LASV strain Josiah from Sierra Leone protects strain 13 guinea pigs from infection / disease following challenge with LASV isolates originating from Liberia, Mali and Nigeria. Similarly, the VSV-based LASV vaccine yields complete protection against a lethal challenge with the Liberian LASV isolate in the gold-standard macaque model of Lassa fever.Our results demonstrate the VSV-based LASV vaccine is capable of preventing morbidity and mortality associated with non-homologous LASV challenge in two animal models of Lassa fever. Additionally, this work highlights the need for the further development of disease models for geographical distinct LASV strains, particularly those from Nigeria, in order to comprehensively evaluate potential vaccines and therapies against this prominent agent of viral hemorrhagic fever.

  8. A Recombinant Vesicular Stomatitis Virus-Based Lassa Fever Vaccine Protects Guinea Pigs and Macaques against Challenge with Geographically and Genetically Distinct Lassa Viruses

    Science.gov (United States)

    Safronetz, David; Mire, Chad; Rosenke, Kyle; Feldmann, Friederike; Haddock, Elaine; Geisbert, Thomas; Feldmann, Heinz

    2015-01-01

    Background Lassa virus (LASV) is endemic in several West African countries and is the etiological agent of Lassa fever. Despite the high annual incidence and significant morbidity and mortality rates, currently there are no approved vaccines to prevent infection or disease in humans. Genetically, LASV demonstrates a high degree of diversity that correlates with geographic distribution. The genetic heterogeneity observed between geographically distinct viruses raises concerns over the potential efficacy of a “universal” LASV vaccine. To date, several experimental LASV vaccines have been developed; however, few have been evaluated against challenge with various genetically unique Lassa virus isolates in relevant animal models. Methodologies/principle findings Here we demonstrate that a single, prophylactic immunization with a recombinant vesicular stomatitis virus (VSV) expressing the glycoproteins of LASV strain Josiah from Sierra Leone protects strain 13 guinea pigs from infection / disease following challenge with LASV isolates originating from Liberia, Mali and Nigeria. Similarly, the VSV-based LASV vaccine yields complete protection against a lethal challenge with the Liberian LASV isolate in the gold-standard macaque model of Lassa fever. Conclusions/significance Our results demonstrate the VSV-based LASV vaccine is capable of preventing morbidity and mortality associated with non-homologous LASV challenge in two animal models of Lassa fever. Additionally, this work highlights the need for the further development of disease models for geographical distinct LASV strains, particularly those from Nigeria, in order to comprehensively evaluate potential vaccines and therapies against this prominent agent of viral hemorrhagic fever. PMID:25884628

  9. Multicriteria Evaluation of Classical Swine Fever Control Strategies Using the Choquet Integral.

    Science.gov (United States)

    Brosig, J; Traulsen, I; Krieter, J

    2016-02-01

    An outbreak of the highly contagious animal disease classical swine fever (CSF) requires the selection of an optimal control strategy. The choice of a control strategy is a decision process depending on different aspects. Besides epidemiology, economic and ethical/social aspects must be taken into account. In this study, multicriteria decision-making (MCDM) was used to evaluate six control strategies for two regions with different farm densities. A strategy including only the minimum EU control measures and the traditional control strategy based on preventive culling were compared to alternative control strategies using emergency vaccination and/or rapid PCR testing ('emergency vaccination', 'test to slaughter', 'test to control' and 'vaccination in conjunction with rapid testing'). The MACBETH approach was used in order to assess the three main criteria (epidemiology, economics and ethical/social aspects). Subcriteria with both quantitative and qualitative performance levels were translated into a normalized scale. The Choquet integral approach was adopted to obtain a ranking of the six CSF control strategies based on the three main criteria, taking interactions into account. Three different rankings of the importance of the main criteria, which were to reflect the potential perceptions of stakeholders, were examined. Both the region under investigation and the ranking of the main criteria had an influence on the 'best' choice. Alternative control strategies were favourable to the minimum EU control and the traditional control measures independent of the farm density. Because the choice of the 'best' control strategy does not solely depend on the epidemiological efficiency, MCDM can help to find the best solution. Both MACBETH and the Choquet integral approach are feasible MCDM approaches. MACBETH only needs a qualitative evaluation and is therefore a comparatively intuitive approach. The Choquet integral does not only take the importance of the criteria into

  10. Socioeconomic status and the prevalence of fever in children under age five: evidence from four sub-Saharan African countries

    OpenAIRE

    Novignon Jacob; Nonvignon Justice

    2012-01-01

    Abstract Background The burden of fevers remains enormous in sub-Saharan Africa. While several efforts at reducing the burden of fevers have been made at the macro level, the relationship between socioeconomic status and fever prevalence has been inconclusive at the household and individual levels. The purpose of this study was to examine how individual and household socioeconomic status influences the prevalence of fever among children under age five in four sub-Saharan African countries. Me...

  11. Nested RT-PCR method for the detection of European avian-like H1 swine inlfuenza A virus

    Institute of Scientific and Technical Information of China (English)

    WEI Yan-di; PEI Xing-yao; ZHANG Yuan; YU Chen-fang; SUN Hong-lei; LIU Jin-hua; PU Juan

    2016-01-01

    Swine inlfuenza A virus (swine IAV) circulates worldwide in pigs and poses a serious public health threat, as evidenced by the 2009 H1N1 inlfuenza pandemic. Among multiple subtypes/lineages of swine inlfuenza A viruses, European avian-like (EA) H1N1 swine IAV has been dominant since 2005 in China and caused infections in humans in 2010. Highly sensitive and speciifc methods of detection are required to differentiate EA H1N1 swine IAVs from viruses belonging to other lineages and subtypes. In this study, a nested reverse transcription (RT)-PCR assay was developed to detect EA H1 swine IAVs. Two primer sets (outer and inner) were designed speciifcaly to target the viral hemagglutinin genes. Speciifc PCR products were obtained from al tested EA H1N1 swine IAV isolates, but not from other lineages of H1 swine IAVs, other subtypes of swine IAVs, or other infectious swine viruses. The sensitivity of the nested RT-PCR was improved to 1 plaque forming unit (PFU) mL–1which was over 104 PFU mL–1 for a previously established multiplex RT-PCR method. The nested RT-PCR results obtained from screening 365 clinical samples were consistent with those obtained using conventional virus isolation methods combined with sequencing. Thus, the nested RT-PCR assay reported herein is more sensitive and suitable for the diagnosis of clinical infections and surveilance of EA H1 swine IAVs in pigs and humans.

  12. Dengue-1 Virus Isolation during First Dengue Fever Outbreak on Easter Island, Chile

    OpenAIRE

    Perret, Cecilia; Abarca, Katia; Ovalle, Jimena; Ferrer, Pablo; Godoy, Paula; Olea, Andrea; Aguilera, Ximena; Ferrés, Marcela

    2003-01-01

    Dengue virus was detected for the first time in Chile, in an outbreak of dengue fever on Easter Island. The virus was isolated in tissue culture and characterized by reverse transcription–polymerase chain reaction as being dengue type 1.

  13. 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.

  14. Molecular Insights into Crimean-Congo Hemorrhagic Fever Virus.

    Science.gov (United States)

    Zivcec, Marko; Scholte, Florine E M; Spiropoulou, Christina F; Spengler, Jessica R; Bergeron, Éric

    2016-01-01

    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. PMID:27110812

  15. 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.

  16. Molecular diagnosis of African tick bite fever using eschar swabs in a traveller returning from Tanzania.

    Science.gov (United States)

    Harrison, Nicole; Burgmann, Heinz; Forstner, Christina; Ramharter, Michael; Széll, Marton; Schötta, Anna-Margarita; Stanek, Gerold; Markowicz, Mateusz

    2016-08-01

    African tick bite fever is an emerging infectious disease among travellers caused by the pathogen Rickettsia africae. Most travel-associated cases have been reported from countries in southern Africa. So far it has rarely been reported among travellers to eastern Africa and our patient is one of the first described cases imported from Tanzania. A woman presented with fever, chills, headache, myalgia and a rickettsial eschar on her ankle after returning from Tanzania. The diagnosis of African tick bite fever is often based on clinical grounds due to a lack of reliable diagnostic tests at commencement of symptoms. In this patient direct molecular detection of R. africae was performed by PCR from a sample obtained non-invasively with a swab from the rickettsial eschar. A positive PCR result was achieved although the patient had already started antibiotic treatment with doxycycline. In conclusion, this non-invasive method enables early diagnosis of African tick bite fever by direct molecular detection of R. africae and might improve the management of undifferentiated fever in travellers from Africa. PMID:27488618

  17. 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......). In the current system, 3.5% of sows and boars for export or slaughter are tested for both diseases, as well as all boars before entering boar stations. Furthermore, nucleus herds are tested every third month for classical swine fever. We investigated, whether the sample size could be reduced without...

  18. Diagnosis of Queensland Tick Typhus and African Tick Bite Fever by PCR of Lesion Swabs

    OpenAIRE

    Wang, Jin-Mei; Hudson, Bernard J.; Watts, Matthew R.; Karagiannis, Tom; Fisher, Noel J.; Anderson, Catherine; Roffey, Paul

    2009-01-01

    We report 3 cases of Queensland tick typhus (QTT) and 1 case of African tick bite fever in which the causative rickettsiae were detected by PCR of eschar and skin lesions in all cases. An oral mucosal lesion in 1 QTT case was also positive.

  19. Porcine epidemic diarrhea virus: An emerging and re-emerging epizootic swine virus.

    Science.gov (United States)

    Lee, Changhee

    2015-01-01

    The enteric disease of swine recognized in the early 1970s in Europe was initially described as "epidemic viral diarrhea" and is now termed "porcine epidemic diarrhea (PED)". The coronavirus referred to as PED virus (PEDV) was determined to be the etiologic agent of this disease in the late 1970s. Since then the disease has been reported in Europe and Asia, but the most severe outbreaks have occurred predominantly in Asian swine-producing countries. Most recently, PED first emerged in early 2013 in the United States that caused high morbidity and mortality associated with PED, remarkably affecting US pig production, and spread further to Canada and Mexico. Soon thereafter, large-scale PED epidemics recurred through the pork industry in South Korea, Japan, and Taiwan. These recent outbreaks and global re-emergence of PED require urgent attention and deeper understanding of PEDV biology and pathogenic mechanisms. This paper highlights the current knowledge of molecular epidemiology, diagnosis, and pathogenesis of PEDV, as well as prevention and control measures against PEDV infection. More information about the virus and the disease is still necessary for the development of effective vaccines and control strategies. It is hoped that this review will stimulate further basic and applied studies and encourage collaboration among producers, researchers, and swine veterinarians to provide answers that improve our understanding of PEDV and PED in an effort to eliminate this economically significant viral disease, which emerged or re-emerged worldwide. PMID:26689811

  20. 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.

  1. Prevalence of Swine Viral and Bacterial Pathogens in Rodents and Stray Cats Captured around Pig Farms in Korea

    OpenAIRE

    TRUONG, Quang Lam; SEO, Tae Won; Yoon, Byung-Il; Kim, Hyeon-Cheol; Han, Jeong Hee; HAHN, Tae-Wook

    2013-01-01

    ABSTRACT In 2008, 102 rodents and 24 stray cats from the areas around 9 pig farms in northeast South Korea were used to determine the prevalence of the following selected swine pathogens: ten viral pathogens [porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis virus (TGEV), rotavirus, classical swine fever virus (CSFV), porcine circovirus type 2 (PCV2), encephalomyocarditis virus (EMCV), porcine reproductive and respiratory syndrome virus (PRRSV), porcine parvovirus (PPV), p...

  2. Simian hemorrhagic fever virus infection of rhesus macaques as a model of viral hemorrhagic fever: Clinical characterization and risk factors for severe disease

    OpenAIRE

    Johnson, Reed F.; Dodd, Lori; Yellayi, Srikanth; Gu, Wenjuan; Cann, Jennifer A.; Jett, Catherine; Bernbaum, John G.; Ragland, Dan R.; Claire, Marisa St.; Byrum, Russell; Paragas, Jason; Blaney, Joseph E.; Jahrling, Peter B

    2011-01-01

    Simian Hemorrhagic Fever Virus (SHFV) has caused sporadic outbreaks of hemorrhagic fevers in macaques at primate research facilities. SHFV is a BSL-2 pathogen that has not been linked to human disease; as such, investigation of SHFV pathogenesis in non-human primates (NHPs) could serve as a model for hemorrhagic fever viruses such as Ebola, Marburg, and Lassa viruses. Here we describe the pathogenesis of SHFV in rhesus macaques inoculated with doses ranging from 50 PFU to 500,000 PFU. Disease...

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

    OpenAIRE

    Dyah Ayu Hewajuli; Ni Luh Putu Indi Dharmiayanti

    2012-01-01

    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 ...

  4. Complete Genome Sequence of an Avian-Like H4N8 Swine Influenza Virus Discovered in Southern China

    OpenAIRE

    Su, Shuo; Qi, Wen-bao; Chen, Ji-dang; Cao, Nan; Zhu, Wan-jun; Yuan, Li-Guo; Wang, Heng; Zhang, Gui-hong

    2012-01-01

    We report here the complete genomic sequence of an avian-like H4N8 swine influenza virus containing an H5N1 avian influenza virus segment from swine in southern China. Phylogenetic analyses of the sequences of all eight viral RNA segments demonstrated that these are wholly avian influenza viruses of the Asia lineage. To our knowledge, this is the first report of interspecies transmission of an avian H4N8 influenza virus to domestic pigs under natural conditions.

  5. Inhibitors of cellular kinases with broad-spectrum antiviral activity for hemorrhagic fever viruses.

    Science.gov (United States)

    Mohr, Emma L; McMullan, Laura K; Lo, Michael K; Spengler, Jessica R; Bergeron, Éric; Albariño, César G; Shrivastava-Ranjan, Punya; Chiang, Cheng-Feng; Nichol, Stuart T; Spiropoulou, Christina F; Flint, Mike

    2015-08-01

    Host cell kinases are important for the replication of a number of hemorrhagic fever viruses. We tested a panel of kinase inhibitors for their ability to block the replication of multiple hemorrhagic fever viruses. OSU-03012 inhibited the replication of Lassa, Ebola, Marburg and Nipah viruses, whereas BIBX 1382 dihydrochloride inhibited Lassa, Ebola and Marburg viruses. BIBX 1382 blocked both Lassa and Ebola virus glycoprotein-dependent cell entry. These compounds may be used as tools to understand conserved virus-host interactions, and implicate host cell kinases that may be targets for broad spectrum therapeutic intervention. PMID:25986249

  6. A socio-psychological investigation into limitations and incentives concerning reporting a clinically suspect situation aimed at improving early detection of classical swine fever outbreaks

    NARCIS (Netherlands)

    Elbers, A.R.W.; Gorgievski-Duijvesteijn, M.J.; Velden, P.G.; Loeffen, W.L.A.; Zarafshani, K.

    2010-01-01

    The aim of this study was to identify limitations and incentives in reporting clinically suspect situations, possibly caused by classical swine fever (CSF), to veterinary authorities with the ultimate aim to facilitate early detection of CSF outbreaks. Focus group sessions were held with policy make

  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...

  8. A common neutralizing epitope on envelope glycoprotein E2 of different pestiviruses: Implications for improvement of vaccines and diagnostics for Classical swine fever (CSF)?

    OpenAIRE

    van Rijn, P A

    2007-01-01

    A common neutralizing epitope on envelope glycoprotein E2 of different pestiviruses: Implications for improvement of vaccines and diagnostics for Classical swine fever (CSF)? NETHERLANDS (van Rijn, P.A.) NETHERLANDS Received: 2007-03-18 Revised: 2007-05-07 Accepted: 2007-05-09

  9. The Study of Immunization Effects on Classical Swine Fever in Some Scale Pig Farms%规模化种猪场猪瘟免疫情况调研

    Institute of Scientific and Technical Information of China (English)

    王娟萍; 姚敬明; 吴忻; 孟帆; 韩一超; 刘文俊; 樊振华; 米瑞娟; 程海龙

    2012-01-01

    Classical swine fever caused by classical swine fever virus is a high fever, bleeding as the main feature of the potent, highly contagious disease and still widely popular in China. Vaccination is the most fundamental methods of the disease prevention and control, in order to identify the immunization effects of classical swine fever in large-scale pig farms of Shanxi, the classical swine fever immune antibody of 465 breast-feeding pigs, 456 nursery pigs, 436 finishing pigs and 419 sows in the 42 scale pig farms of eight cities were detected by ELISA kits. The test identified the antibody positive rate of breast-feeding pigs averaged of 70. 11%, the antibody positive rate of nursery pigs averaged 40. 57%, the antibody positive rate of finishing pigs averaged 50. 22% and the antibody positive rate of sows averaged 69. 69%. It was seized that the immune antibody of the swinery detected was not ideal, especially lower antibody levels in nursery pigs. While the immune antibody of 133 breast-feeding pigs, 110 nursery pigs, 105 finishing pigs and 135 sows with four different types of classical swine fever vaccine immunity in the 12 large-scale pig farms was detected. The results showed that porket were hyper immunized firstly six copies of classical swine fever efficient cell-free vaccine at birth, then piglets were immunized secondly four copies at two 21-day-old, at last piglets were immunized thirdly two copies at 60-day-old, besides, it was best that postpartum sows were immunized with fetal immunity after 21 days, so that the antibody positive rate of nursery pigs could reach 89. 29% , therefore, the mortality of nurser-y pigs reduced evidently and the growth and development of pigs walk gradually up to normal after using this immune method in some pig farms, while the use of the worst method that the first immunization of piglets between 28-day-old and 35-day-old with four copies of classical swine fever normal cell-free vaccine after ablactation, the second

  10. SWINE FLU (H1N1 VIRUS, PREVENTION AND THEIR TREATMENT: A REVIEW

    Directory of Open Access Journals (Sweden)

    Jaiswal Amit

    2011-05-01

    Full Text Available Swine flu has been confirmed in a number of countries and it is spreading from human to human, which could lead to what is referred to as a pandemic flu outbreak. Pandemic flu is different from ordinary flu because it’s a new flu virus that appears in humans and spreads very quickly from person to person worldwide. The World Health Organization (WHO is closely monitoring cases of swine flu globally to see whether this virus develops into a pandemic. Because it’s a new virus, no one will have immunity to it and everyone could be at risk of catching it. This includes healthy adults as well as older people, young children and those with existing medical conditions. Tamiflu (Oseltamivir and Ralenza (Zanamivir can treat the H1 N1 swine flu strain.

  11. Protein Phosphatase-1 regulates Rift Valley fever virus replication.

    Science.gov (United States)

    Baer, Alan; Shafagati, Nazly; Benedict, Ashwini; Ammosova, Tatiana; Ivanov, Andrey; Hakami, Ramin M; Terasaki, Kaori; Makino, Shinji; Nekhai, Sergei; Kehn-Hall, Kylene

    2016-03-01

    Rift Valley fever virus (RVFV), genus Phlebovirus family Bunyaviridae, is an arthropod-borne virus endemic throughout sub-Saharan Africa. Recent outbreaks have resulted in cyclic epidemics with an increasing geographic footprint, devastating both livestock and human populations. Despite being recognized as an emerging threat, relatively little is known about the virulence mechanisms and host interactions of RVFV. To date there are no FDA approved therapeutics or vaccines for RVF and there is an urgent need for their development. The Ser/Thr protein phosphatase 1 (PP1) has previously been shown to play a significant role in the replication of several viruses. Here we demonstrate for the first time that PP1 plays a prominent role in RVFV replication early on during the viral life cycle. Both siRNA knockdown of PP1α and a novel PP1-targeting small molecule compound 1E7-03, resulted in decreased viral titers across several cell lines. Deregulation of PP1 was found to inhibit viral RNA production, potentially through the disruption of viral RNA transcript/protein interactions, and indicates a potential link between PP1α and the viral L polymerase and nucleoprotein. These results indicate that PP1 activity is important for RVFV replication early on during the viral life cycle and may prove an attractive therapeutic target. PMID:26801627

  12. Evaluation of Screening Assays for the Detection of Influenza A Virus Serum Antibodies in Swine.

    Science.gov (United States)

    Goodell, C K; Prickett, J; Kittawornrat, A; Johnson, J; Zhang, J; Wang, C; Zimmerman, J J

    2016-02-01

    Increased surveillance of influenza A virus (IAV) infections in human and swine populations is mandated by public health and animal health concerns. Antibody assays have proven useful in previous surveillance programmes because antibodies provide a record of prior exposure and the technology is inexpensive. The objective of this research was to compare the performance of influenza serum antibody assays using samples collected from pigs (vaccinated or unvaccinated) inoculated with either A/Swine/OH/511445/2007 γ H1N1 virus or A/Swine/Illinois/02907/2009 Cluster IV H3N2 virus and followed for 42 days. Weekly serum samples were tested for anti-IAV antibodies using homologous and heterologous haemagglutination-inhibition (HI) assays, commercial swine influenza H1N1 and H3N2 indirect ELISAs, and a commercial influenza nucleoprotein (NP)-blocking ELISA. The homologous HIs showed 100% diagnostic sensitivity, but largely failed to detect infection with the heterologous virus. With diagnostic sensitivities of 1.4% and 4.9%, respectively, the H1N1 and H3N2 indirect ELISAs were ineffective at detecting IAV antibodies in swine infected with the contemporary influenza viruses used in the study. At a cut-off of S/N ≤ 0.60, the sensitivity and specificity of the NP-blocking ELISA were estimated at 95.5% and 99.6%, respectively. Statistically significant factors which affected S/N results include vaccination status, inoculum (virus subtype), day post-inoculation and the interactions between those factors (P cost-effective approach for the detection and surveillance of IAV infections in swine populations. PMID:24571447

  13. 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.

  14. Enhanced protective immunity of the chimeric vector-based vaccine rAdV-SFV-E2 against classical swine fever in pigs by a Salmonella bacterial ghost adjuvant.

    Science.gov (United States)

    Xia, Shui-Li; Lei, Jian-Lin; Du, Mingliang; Wang, Yimin; Cong, Xin; Xiang, Guang-Tao; Li, Lian-Feng; Yu, Shenye; Du, Enqi; Liu, Siguo; Sun, Yuan; Qiu, Hua-Ji

    2016-01-01

    Classical swine fever (CSF) is a highly contagious swine disease caused by classical swine fever virus (CSFV). Previously, we demonstrated that rAdV-SFV-E2, an adenovirus-delivered, Semliki Forest virus replicon-vectored marker vaccine against CSF, is able to protect pigs against lethal CSFV challenge. From an economical point of view, it will be beneficial to reduce the minimum effective dose of the vaccine. This study was designed to test the adjuvant effects of Salmonella enteritidis-derived bacterial ghosts (BG) to enhance the protective immunity of rAdV-SFV-E2 in pigs. Groups of 5-week-old pigs (n = 4) were immunized intramuscularly twice with 10(5) median tissue culture infective doses (TCID50) rAdV-SFV-E2 combined with 10(10) colony forming units (CFU) BG, 10(6) or 10(5) TCID50 rAdV-SFV-E2 alone or 10(10) CFU BG alone at an interval of 3 weeks, and challenged with the highly virulent CSFV Shimen strain at 1 week post-booster immunization. The results show that the pigs inoculated with 10(5) TCID50 rAdV-SFV-E2 plus BG or 10(6) TCID50 rAdV-SFV-E2 alone were completely protected from lethal CSFV challenge, in contrast with the pigs vaccinated with 10(5) TCID50 rAdV-SFV-E2 or BG alone, which displayed partial or no protection following virulent challenge. The data indicate that BG are a promising adjuvant to enhance the efficacy of rAdV-SFV-E2 and possibly other vaccines. PMID:27301745

  15. [South African tick bite fever in a group of Russian tourists].

    Science.gov (United States)

    Kozhevnikova, G M; Tokmalaev, A K; Voznesensky, S L; Karan, L S

    2014-01-01

    The paper describes a clinical case of South African tick bite fever in a group of Russian tourists. The group of 5 people who had been ill with this disease after a tourist trip to the South African Republic (the Kruger National Park in the north-eastern province of Mpumalanga) were followed up. During their trip, all of them were bitten by different insects many times. The disease exhibited different clinical presentations; however, all the patients were noted to have a fever with slight intoxication and a maculopapular rash at different sites of the body; 3 had lymphadenopathy and one had a primary effect at the site of tick sticking. The diagnosis was verified by indirect immunofluorescence for the detection of high titers to Rickettsia conorii. The course of the disease was favorable in all the patients treated with antibiotics (doxycycline or ceftriaxone). PMID:25715493

  16. Infective viruses produced from full-length complementary DNA of swine vesicular disease viruses HK/70 strain

    Institute of Scientific and Technical Information of China (English)

    ZHENG Haixue; FENG Xia; YIN Shuanghui; GUO Jianhong; CONG Guozheng; LIU Zaixin; CHANG Huiyun; MA Junwu; XIE Qingge; LIU Xiangtao; SHANG Youjun; WU Jinyan; BAI Xingwen; JIN Ye; SUN Shiqi; GUO Huichen; TIAN Hong

    2006-01-01

    The full-length cDNA clone of swine vesicular disease virus HK/70 strain named pSVOK12 was constructed in order to study the antigenicity, replication, maturation and pathogenicity of swine vesicular disease virus. In vitro transcription RNA from pSVOK12 transfected IBRS-2 cells and the recovered virus RNA were isolated and sequenced, then indirect hemagglutination test, indirect immunofluorescence assays, eleectron microscope test, 50% tissue culture infecting dose (TCID50) assays and mouse virulence studies were performed to study the antigenicity and virulence of the recovered virus. The result showed that the infectious clones we obtained and the virus derived from pSVOK12 had the same biological properties as the parental strain HK/70. The full-length infectious cDNA clone, pSVOK12, will be very useful in studies of the antigenicity, virulence, pathogenesis, maturation and replication of SVDV.

  17. Dengue virus identification by transmission electron microscopy and molecular methods in fatal dengue hemorrhagic fever.

    Science.gov (United States)

    Limonta, D; Falcón, V; Torres, G; Capó, V; Menéndez, I; Rosario, D; Castellanos, Y; Alvarez, M; Rodríguez-Roche, R; de la Rosa, M C; Pavón, A; López, L; González, K; Guillén, G; Diaz, J; Guzmán, M G

    2012-12-01

    Dengue virus is the most significant virus transmitted by arthropods worldwide and may cause a potentially fatal systemic disease named dengue hemorrhagic fever. In this work, dengue virus serotype 4 was detected in the tissues of one fatal dengue hemorrhagic fever case using electron immunomicroscopy and molecular methods. This is the first report of dengue virus polypeptides findings by electron immunomicroscopy in human samples. In addition, not-previously-documented virus-like particles visualized in spleen, hepatic, brain, and pulmonary tissues from a dengue case are discussed. PMID:22527878

  18. 143 Rift Valley fever virus: A virus with potential for global emergence

    OpenAIRE

    Paweska, Janusz T.

    2014-01-01

    The capacity of Rift Valley fever virus (RVFV) to spread into new territories by crossing significant natural geographic barriers, re-emerge in endemic regions after long periods of silence to cause large outbreaks in human and animal populations constitute a formidable challenge for public and veterinary health authorities as well as for scientific communities worldwide. In spite of recent advances in research on RVFV pathogenesis, molecular epidemiology, outbreak prediction, development of ...

  19. Dengue Virus Serotype 2 from a Sylvatic Lineage Isolated from a Patient with Dengue Hemorrhagic Fever

    OpenAIRE

    Jane Cardosa; Mong How Ooi; Phaik Hooi Tio; David Perera; Edward C Holmes; Khatijar Bibi; Zahara Abdul Manap

    2009-01-01

    Author Summary Dengue viruses are mosquito-borne RNA viruses that cause a spectrum of illness from mild disease to life-threatening dengue hemorrhagic fever (DHF). Dengue viruses exist in two separate cycles in nature, circulating in either non-human primates or humans. The viruses that are endemic in humans today most likely evolved from non-human primate dengue viruses a few hundred years ago and have since established themselves as four distinct serotypes in human populations, causing peri...

  20. Nasal Wipes for Influenza A Virus Detection and Isolation from Swine.

    Science.gov (United States)

    Nolting, Jacqueline M; Szablewski, Christine M; Edwards, Jody L; Nelson, Sarah W; Bowman, Andrew S

    2015-01-01

    Surveillance for influenza A viruses in swine is critical to human and animal health because influenza A virus rapidly evolves in swine populations and new strains are continually emerging. Swine are able to be infected by diverse lineages of influenza A virus making them important hosts for the emergence and maintenance of novel influenza A virus strains. Sampling pigs in diverse settings such as commercial swine farms, agricultural fairs, and live animal markets is important to provide a comprehensive view of currently circulating IAV strains. The current gold-standard ante-mortem sampling technique (i.e. collection of nasal swabs) is labor intensive because it requires physical restraint of the pigs. Nasal wipes involve rubbing a piece of fabric across the snout of the pig with minimal to no restraint of the animal. The nasal wipe procedure is simple to perform and does not require personnel with professional veterinary or animal handling training. While slightly less sensitive than nasal swabs, virus detection and isolation rates are adequate to make nasal wipes a viable alternative for sampling individual pigs when low stress sampling methods are required. The proceeding protocol outlines the steps needed to collect a viable nasal wipe from an individual pig. PMID:26709840

  1. Investigations on the inactivation of selected bacteria and viruses during mesophilic and thermophilic anaerobic alkaline cofermentation of biological waste materials, food residues and other animal residues; Seuchenhygienische Untersuchungen zur Inaktivierung ausgewaehlter Bakterien und Viren bei der mesophilen und thermophilen anaeroben alkalischen Faulung von Bio- und Kuechenabfaellen sowie anderen Rest- und Abfallstoffen tierischer Herkunft

    Energy Technology Data Exchange (ETDEWEB)

    Hoferer, M. [Hohenheim Univ., Stuttgart (Germany). Inst. fuer Umwelt- und Tierhygiene sowie Tiermedizin mit Tierklinik

    2001-07-01

    The purpose of this study is to investigate the inactivation kinetics of a number of different bacteria (Salmonella Senftenberg, Escherichia coli O157, Enterococcus faecium) and viruses (Bovine Enterovirus (ECBO), Equine Rhinovirus (ERV), Poliovirus, Bovine Parvovirus (BPV)) during the process of anaerobic cofermentation. Experiments were conducted in a semi-technical biogas plant at the University of Hohenheim. The fermenter was fed with a mixture of slurry from pigs or cattle (75%) and leftovers (25%) and was run under mesophilic (30 C + 35 C) as well as under thermophilic temperature conditions (50 C + 55 C). Volume and filter-sandwich germ-carriers were specifically developed and/or optimised for these analyses. Parallel to the experiments at the University of Hohenheim and under almost identical process conditions, various viruses (African Swine Fever Virus, Pseudorabies Virus, Classical Swine Fever Virus, Foot and Mouth Disease Virus, Swine Vesicular Disease Virus) were examined at the Federal Research Centre for Virus Diseases of Animals in Tuebingen. The results obtained at each research institution are directly compared. (orig.)

  2. 猪瘟疫苗研究进展%Research Progress of the Vaccine of Classical Swine Fever

    Institute of Scientific and Technical Information of China (English)

    胡鸿惠; 娄高明

    2012-01-01

    The current research situation of CSF vaccine is reviewed in this article. The research progress of traditional vaccine and new vaccine is described, which is refer to further research of CSF vaccine. It is also better for controlling CSF and making out immunization programs.%文章综述了国内外猪瘟(classical swine fever,CSF)疫苗的研究现状.对灭活疫苗、弱毒疫苗和新型疫苗的研究情况进行概述,重点阐述了新型疫苗的研究进展,为进一步研究和开发新的猪瘟疫苗、制定良好猪瘟免疫方案有效控制猪瘟提供参考.

  3. 猪瘟疫苗的研究进展%Reseach Strategy on the Vaccine of Classical Swine Fever

    Institute of Scientific and Technical Information of China (English)

    刘萍

    2008-01-01

    猪瘟(classical swine fever,CSF)是危害世界养猪业的主要传染病之一,以很强的传染性和高致死率为特征.目前猪瘟的流行趋势发生了很大变化,呈现典型猪瘟和非典型猪瘟共存、持续感染与隐性感染共存、免疫耐受和带毒综合征共存等现象,给猪瘟的防制带来新的挑战.目前,免疫接种依然是猪瘟防制的主要措施,因而开发新型、高效,稳定的猪瘟标记疫苗具有重要的现实意义.

  4. Efficacy and safety of a live canine adenovirus-vectored rabies virus vaccine in swine.

    Science.gov (United States)

    Liu, Ye; Zhang, Shoufeng; Ma, Guangpeng; Zhang, Fei; Hu, Rongliang

    2008-10-01

    Rabies infections in swine have been reported occasionally in recent years in certain geographic locations. Although a protective vaccine consisting of inactivated rabies virus is available for use in swine, searching for a more economically viable formulation for use in developing countries is always a priority. This work describes the testing of a canine adenovirus that expresses a rabies viral epitope (CAV-2-E3Delta-RGP) in a porcine rabies model. The data presented here show that the recombinant viral vaccine was effective in protecting swine against rabies if administered intramuscularly, but not orally or intranasally, and that protection was probably related to the development of a humoral response that lasted at least 28 weeks. Following vaccination, no behavioral abnormalities were observed in vaccinated swine and virus particles were not detected in either tissues or body fluids, indicating that this formulation was safe. The recombinant virus stimulated an effective level of antibody response in the immunized swine after a single intramuscular inoculation. PMID:18721839

  5. The progress of monoclonal antibodies applied in the diagnosis of classical swine fever%猪瘟单克隆抗体诊断方法的研究概述

    Institute of Scientific and Technical Information of China (English)

    李娇; 王艳; 唐娜; 沈志强

    2011-01-01

    猪瘟单克隆抗体以其敏感性高、特异性强、能够识别病毒抗原结构的微小差异,同时单抗特有的理化同质性使抗原抗体反应结果便于质量控制、利于标准化和规范化等优点,在猪瘟病毒的诊断以及强弱毒鉴别诊断中得到了广泛应用,显示出良好的应用前景。本文就猪瘟单克隆抗体及其在猪瘟诊断中的应用进展作一综述。%CSF monoclonal antibody of its high sensitivity and specificity,can identify small differences in the structure of viral antigen,while monoclonal antibody specific to the physical and chemical homogeneity of the antigen-antibody reaction results to facilitate quality control,standardization and standardized benefit advantages, such as classical swine fever virus diagnosis and differential diagnosis of attenuated intensity is widely used, showing a good prospect.In this paper, monoelonal antibodies to classical swine fever and its application in diagnosis are reviewed.

  6. Hiding the evidence: two strategies for innate immune evasion by hemorrhagic fever viruses

    OpenAIRE

    Hastie, Kathryn M.; Bale, Shridhar; Kimberlin, Christopher R.; Saphire, Erica Ollmann

    2012-01-01

    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 vir...

  7. Viral metagenomics demonstrates that domestic pigs are a potential reservoir for Ndumu virus

    Directory of Open Access Journals (Sweden)

    Masembe Charles

    2012-09-01

    Full Text Available Abstract Background The rising demand for pork has resulted in a massive expansion of pig production in Uganda. This has resulted in increased contact between humans and pigs. Pigs can act as reservoirs for emerging infectious diseases. Therefore identification of potential zoonotic pathogens is important for public health surveillance. In this study, during a routine general surveillance for African swine fever, domestic pigs from Uganda were screened for the presence of RNA and DNA viruses using a high-throughput pyrosequencing method. Findings Serum samples from 16 domestic pigs were collected from five regions in Uganda and pooled accordingly. Genomic DNA and RNA were extracted and sequenced on the 454 GS-FLX platform. Among the sequences assigned to a taxon, 53% mapped to the domestic pig (Sus scrofa. African swine fever virus, Torque teno viruses (TTVs, and porcine endogenous retroviruses were identified. Interestingly, two pools (B and C of RNA origin had sequences that showed 98% sequence identity to Ndumu virus (NDUV. None of the reads had identity to the class Insecta indicating that these sequences were unlikely to result from contamination with mosquito nucleic acids. Conclusions This is the first report of the domestic pig as a vertebrate host for Ndumu virus. NDUV had been previously isolated only from culicine mosquitoes. NDUV therefore represents a potential zoonotic pathogen, particularly given the increasing risk of human-livestock-mosquito contact.

  8. 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.

  9. 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.

  10. 9 CFR 94.9 - Pork and pork products from regions where classical swine fever exists.

    Science.gov (United States)

    2010-01-01

    ... and 0579-0333) Editorial Note: For Federal Register citations affecting § 94.9, see the List of CFR... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Pork and pork products from regions... AND RESTRICTED IMPORTATIONS § 94.9 Pork and pork products from regions where classical swine...

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

    DEFF Research Database (Denmark)

    Inoue, Toru; Zhang, Zhidong; Wang, Leyuan; West, Laura; Bashiruddin, John B.; Belsham, Graham

    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...

  12. 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; Wadsworth, Jemma; Knowles, Nick J.; Gilbert, M. Thomas P.

    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 r...

  13. The repeated introduction of the H3N2 virus from human to swine during 1979-1993 in China.

    Science.gov (United States)

    Zhu, Wenfei; Yang, Shuai; Dong, Libo; Yang, Lei; Tang, Jing; Zou, Xiaohui; Chen, Tao; Yang, Jing; Shu, Yuelong

    2015-07-01

    Limited data are available regarding the swine influenza viruses (SIVs) that circulated in Mainland China prior to the 1990s. Eleven H3N2 virus strains were isolated from swine populations from 1979 to 1992. To determine the origin and tendency of these SIVs, the phylogenetic and antigenic properties of these viruses were analyzed based on the whole genome sequenced and the HI titrations with post-infection ferret antisera against influenza A (H3N2) virus isolates of swine and human origin. The results revealed that these 11 SIVs originated from humans and were not maintained in swine populations, indicating the interspecies transmission from humans to pigs occurred frequently and independently throughout these periods. However, human H3N2 viruses might not have the ability to circulate in pig herds. PMID:25858119

  14. 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. PMID:26808727

  15. Failure of protection and enhanced pneumonia with a US H1N2 swine influenza virus in pigs vaccinated with an inactivated classical swine H1N1 vaccine

    Science.gov (United States)

    We evaluated two US swine influenza virus (SIV) isolates, A/Swine/Iowa/15/1930 H1N1 (IA30) and A/Swine/Minnesota/00194/2003 H1N2 (MN03), with substantial genetic variation in the HA gene and failure to cross-react in the hemagglutination inhibition (HI) assay, in an in vivo vaccination and challenge...

  16. Dengue hemorrhagic fever

    Science.gov (United States)

    Hemorrhagic dengue; Dengue shock syndrome; Philippine hemorrhagic fever; Thai hemorrhagic fever; Singapore hemorrhagic fever ... Four different dengue viruses are known to cause dengue hemorrhagic fever. Dengue hemorrhagic fever occurs when a person is bitten by ...

  17. Complete Genome Sequences of Six Avian-Like H1N1 Swine Influenza Viruses from Northwestern China

    OpenAIRE

    Wang, Jing-Yu; Ren, Juan-Juan; Qiu, Yuan-Hao; Liu, Hung-Jen

    2013-01-01

    Very little is known about swine influenza in northwestern China. Here, we report the complete genomic sequences of six avian-like H1N1 swine influenza viruses (SIVs) isolated in pigs in northwestern China. Phylogenetic analyses of the sequences of eight genomic segments demonstrated that they are avian-like H1N1 SIVs.

  18. Swine-origin influenza-virus-induced acute lung injury:Novel or classical pathogenesis?

    Institute of Scientific and Technical Information of China (English)

    Naoyoshi; Maeda; Toshimitsu; Uede

    2010-01-01

    Influenza viruses are common respiratory pathogens in humans and can cause serious infection that leads to the development of pneumonia.Due to their hostrange diversity,genetic and antigenic diversity,and potential to reassort genetically in vivo,influenza A viruses are continual sources of novel influenza strains that lead to the emergence of periodic epidemics and outbreaks in humans.Thus,newly emerging viral diseases are always major threats to public health.In March 2009,a novel influenza virus suddenly emerged and caused a worldwide pandemic.The novel pandemic influenza virus was genetically and antigenically distinct from previous seasonal human influenza A/H1N1 viruses;it was identified to have originated from pigs,and further genetic analysis revealed it as a subtype of A/H1N1,thus later called a swine-origin influenza virus A/H1N1.Since the novel virus emerged,epidemiological surveys and research on experimental animal models have been conducted,and characteristics of the novel influenza virus have been determined but the exact mechanisms of pulmonary pathogenesis remain to be elucidated.In this editorial,we summa-rize and discuss the recent pandemic caused by the novel swine-origin influenza virus A/H1N1 with a focus on the mechanism of pathogenesis to obtain an insight into potential therapeutic strategies.

  19. 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.

  20. Experimental infection with H1N1 European swine influenza virus protects pigs from an infection with the 2009 pandemic H1N1 human influenza virus

    OpenAIRE

    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

    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 curren...

  1. Molecular epidemiology of Rift Valley fever virus based on genetic analysis of the virus isolates recovered in 1944-2008 from distinct geographic regions

    International Nuclear Information System (INIS)

    Full text: Rift Valley fever (RVF) is an emerging mosquito-borne viral zoonosis caused by a RNA virus named Rift Valley fever virus (RVFV), a Phlebovirus member of the Bunyaviridae family. Historically the disease was present in Africa and Madagascar where outbreaks occur at irregular intervals when heavy rains facilitate the breeding of vector competent mosquito vectors. The occurrence of the first confirmed outbreaks of RVF in 2000-2001 among humans and livestock outside Africa, in the Arabian Peninsula, carries the implication of further spread of infection into non-endemic areas since the virus is capable of utilizing a wide range of mosquito vectors. This work undertook investigation of the molecular epidemiology of the disease (1944-2008) with special reference to South Africa where the first documented outbreak of RVF occurred in 1951 and the most recent in 2008. A total of 149 isolates of RVF recovered over a period of 65 years from various hosts and during endemic and epidemic periods of disease in 15 African countries, Madagascar and Saudi Arabia were characterised by partial genomic sequencing of a 535-nucleotide segment of the G2 glycoprotein coding region of the M segment and the genetic relatedness determined using MEGA software. Pair-wise comparison of RVF isolates revealed divergences ranging from 0-5.6% at the nucleotide level, corresponding to 0-2.8% at the amino acid level. Most isolates are compartmentalized geographically and belong to one of 16 genotypes within three main lineages. Isolates from South Africa collected over 57 years belong to one of 4 genotypes. The 2008 South African isolates were closely related to isolates from the recent east African outbreak in 2006 and a 2003 Mauritanian isolate. Phylogenetic analysis indicates that circulation of RVFV is highly compartmentalized but with favourable climatic conditions a single genotype can rapidly spread from endemic areas over vast distances to cause outbreaks in susceptible human and

  2. Evaluation of the spatial patterns and risk factors, including backyard pigs, for classical swine fever occurrence in Bulgaria using a Bayesian model

    OpenAIRE

    Beatriz Martínez-López; Tsviatko Alexandrov; Lina Mur; Fernando Sánchez-Vizcaíno; Sánchez-Vizcaíno, José M.

    2014-01-01

    The spatial pattern and epidemiology of backyard pig farming and other low bio-security pig production systems and their role in the occurrence of classical swine fever (CSF) is described and evaluated. A spatial Bayesian model was used to explore the risk factors, including human demographics, socioeconomic and environmental factors. The analyses were performed for Bulgaria, which has a large number of backyard farms (96% of all pig farms in the country are classified as backyard farms), and...

  3. Zika Virus Infection and Zika Fever: Frequently Asked Questions

    Science.gov (United States)

    ... Frequently asked questions Updated: 25 March 2016 ABOUT ZIKA What is Zika virus infection? Zika virus infection is caused by ... possible to characterize the disease better. How is Zika virus transmitted? Zika virus is transmitted to people ...

  4. Utility of Antibody Avidity for Rift Valley Fever Virus Vaccine Potency and Immunogenicity Studies

    Science.gov (United States)

    Disease outbreaks caused by arthropod-borne animal viruses (arboviruses) resulting in significant livestock and economic losses world-wide appear to be increasing. Rift Valley fever (RVF) virus is an important arbovirus that causes lethal disease in cattle, camels, sheep and goats in sub-Saharan Afr...

  5. Dengue-1 virus isolation during first dengue fever outbreak on Easter Island, Chile.

    Science.gov (United States)

    Perret, Cecilia; Abarca, Katia; Ovalle, Jimena; Ferrer, Pablo; Godoy, Paula; Olea, Andrea; Aguilera, Ximena; Ferrés, Marcela

    2003-11-01

    Dengue virus was detected for the first time in Chile, in an outbreak of dengue fever on Easter Island. The virus was isolated in tissue culture and characterized by reverse transcription-polymerase chain reaction as being dengue type 1. PMID:14718094

  6. Severe Fever with Thrombocytopenia Syndrome Virus in Ticks Collected from Humans, South Korea, 2013

    OpenAIRE

    Yun, Seok-Min; Lee, Wook-Gyo; Ryou, Jungsang; Yang, Sung-Chan; Park, Sun-Whan; Roh, Jong Yeol; Lee, Ye-Ji; Park, Chan; Han, Myung Guk

    2014-01-01

    We investigated the infection rate for severe fever with thrombocytopenia syndrome virus (SFTSV) among ticks collected from humans during May–October 2013 in South Korea. Haemaphysalis longicornis ticks have been considered the SFTSV vector. However, we detected the virus in H. longicornis, Amblyomma testudinarium, and Ixodes nipponensis ticks, indicating additional potential SFTSV vectors.

  7. Genomic Analysis of One Chinese H1N1 Swine Influenza Virus Strain from Healthy Pig Remaining Different Virulence Determinants

    Directory of Open Access Journals (Sweden)

    Lin Zhi-Xiong

    2012-01-01

    Full Text Available The outbreak of Mexico flu pandemic in the Spring of 2009 has arisen the public attention to swine H1N1 influenza virus because H1N1 influenza virus did not bring a large-scale outbreak in human after causing 1918 Spain flu pandemic. Researchers isolated one swine influenza virus strain A/swine/Guangdong/103/2002 (H1N1 from healthy pig in South China and sequenced its full-length genome. BLASTn analysis showed that all segments of the isolate had the above 99% similarities with A/swine/Shanghai/1/2005, A/swine/Shanghai/2/2005 and A/swine/Shanghai/3/2005 from the severe outbreak of respiratory disease pigs. Although, these four virus strains have high similarities they showed very different virulence. The H1N1 virus could replicate in pigs and mousse without causing clinical symptoms according to the animal regressive experiments results. None of the amino acid substitutions were reported to contribute in the pathogenicity of human and avian influenza viruses providing the basis for virulence determinants research by means of reverse genetics.

  8. Differentiation of strains of yellow fever virus in γ-irradiated mice

    International Nuclear Information System (INIS)

    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)

  9. Dengue virus serotype 2 from a sylvatic lineage isolated from a patient with dengue hemorrhagic fever.

    Directory of Open Access Journals (Sweden)

    Jane Cardosa

    Full Text Available Dengue viruses circulate in both human and sylvatic cycles. Although dengue viruses (DENV infecting humans can cause major epidemics and severe disease, relatively little is known about the epidemiology and etiology of sylvatic dengue viruses. A 20-year-old male developed dengue hemorrhagic fever (DHF with thrombocytopenia (12,000/ul and a raised hematocrit (29.5% above baseline in January 2008 in Malaysia. Dengue virus serotype 2 was isolated from his blood on day 4 of fever. A phylogenetic analysis of the complete genome sequence revealed that this virus was a member of a sylvatic lineage of DENV-2 and most closely related to a virus isolated from a sentinel monkey in Malaysia in 1970. This is the first identification of a sylvatic DENV circulating in Asia since 1975.

  10. Epidemiological study of Rift Valley fever virus in Kigoma, Tanzania

    Directory of Open Access Journals (Sweden)

    Emmanuel G. Kifaro

    2014-04-01

    Full Text Available Rift Valley fever virus (RVFV is an acute, zoonotic viral disease caused by a  Phlebovirus, which belongs to the Bunyaviridae family. Among livestock, outbreaks of the disease are economically devastating. They are often characterised by large, sweeping abortion storms and have significant mortality in adult livestock. The aim of the current study was to investigate RVFV infection in the Kigoma region, which is nestled under the hills of the western arm of the Great Rift Valley on the edge of Lake Tanganyika, Tanzania. A region-wide serosurvey was conducted on non-vaccinated small ruminants (sheep and goats, n = 411. Sera samples were tested for the presence of anti-RVFV antibodies and viral antigen, using commercial enzyme-linked immunosorbent assay and reverse transcriptase polymerase chain reaction, respectively. The overall past infections were detected in 22 of the 411 animals, 5.4% (Confidence Interval (CI 95% = 3.5% – 8.1%. The Kigoma rural area recorded the higher seroprevalence of 12.0% (CI 95% = 7.3% – 18.3%; p < 0.0001, followed by Kibondo at 2.3% (CI 95% = 0.5% – 6.5%; p > 0.05 and the Kasulu district at 0.8% (CI 95% = 0.0% – 4.2%; p > 0.05. The prevalence was 12.5% and 4.7% for sheep and goats, respectively. Reverse transcriptase polymerase chain reaction results indicated that only eight samples were found to be positive (n = 63. This study has confirmed, for the first time, the presence of the RVFV in the Kigoma region four years after the 2007 epizootic in Tanzania. The study further suggests that the virus activity exists during the inter-epizootic period, even in regions with no history of RVFV.

  11. The influence of between-farm distance and farm size on the spread of classical swine fever during the 1997-1998 epidemic in The Netherlands.

    Directory of Open Access Journals (Sweden)

    Gert Jan Boender

    Full Text Available As the size of livestock farms in The Netherlands is on the increase for economic reasons, an important question is how disease introduction risks and risks of onward transmission scale with farm size (i.e. with the number of animals on the farm. Here we use the epidemic data of the 1997-1998 epidemic of Classical Swine Fever (CSF Virus in The Netherlands to address this question for CSF risks. This dataset is one of the most powerful ones statistically as in this epidemic a total of 428 pig farms where infected, with the majority of farm sizes ranging between 27 and 1750 pigs, including piglets. We have extended the earlier models for the transmission risk as a function of between-farm distance, by adding two factors. These factors describe the effect of farm size on the susceptibility of a 'receiving' farm and on the infectivity of a 'sending' farm (or 'source' farm, respectively. Using the best-fitting model, we show that the size of a farm has a significant influence on both farm-level susceptibility and infectivity for CSF. Although larger farms are both more susceptible to CSF and, when infected, more infectious to other farms than smaller farms, the increase is less than linear. The higher the farm size, the smaller the effect of increments of farm size on the susceptibility and infectivity of a farm. Because of changes in the Dutch pig farming characteristics, a straightforward extrapolation of the observed farm size dependencies from 1997/1998 to present times would not be justified. However, based on our results one may expect that also for the current pig farming characteristics in The Netherlands, farm susceptibility and infectivity depend non-linearly on farm size, with some saturation effect for relatively large farm sizes.

  12. New insights on the management of wildlife diseases using multi-state recapture models: the case of classical swine fever in wild boar.

    Directory of Open Access Journals (Sweden)

    Sophie Rossi

    Full Text Available BACKGROUND: 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. METHODOLOGY/PRINCIPAL FINDINGS: 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. CONCLUSIONS/SIGNIFICANCE: 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.

  13. Stampidine prevents mortality in an experimental mouse model of viral hemorrhagic fever caused by lassa virus

    OpenAIRE

    Tibbles Heather E; Vassilev Alexei O; Petkevich Alexander S; Uckun Fatih M; Titov Leonid

    2004-01-01

    Abstract Background The potential use of microorganisms as agents of biological warfare (BW) is a growing concern. Lassa virus, a member of the Arenavirus class of Hemorrhagic fever (HF) viruses has emerged as a worldwide concern among public health officials. The purpose of the present study was to further elucidate the antiviral activity spectrum of stampidine, a novel nucleoside analog with potent anti-viral activity against the immunodeficiency viruses HIV-1, HIV-2, and FIV, by examining ...

  14. Characterization of the Interaction of Lassa Fever Virus with Its Cellular Receptor α-Dystroglycan

    OpenAIRE

    Kunz, Stefan; Rojek, Jillian M.; Perez, Mar; Spiropoulou, Christina F.; Oldstone, Michael B. A.

    2005-01-01

    The cellular receptor for the Old World arenaviruses Lassa fever virus (LFV) and lymphocytic choriomeningitis virus (LCMV) has recently been identified as α-dystroglycan (α-DG), a cell surface receptor that provides a molecular link between the extracellular matrix and the actin-based cytoskeleton. In the present study, we show that LFV binds to α-DG with high affinity in the low-nanomolar range. Recombinant vesicular stomatitis virus pseudotyped with LFV glycoprotein (GP) adopted the recepto...

  15. Calcium Regulation of Hemorrhagic Fever Virus Budding: Mechanistic Implications for Host-Oriented Therapeutic Intervention

    OpenAIRE

    Han, Ziying; Madara, Jonathan J.; Herbert, Andrew; Prugar, Laura I.; Ruthel, Gordon; Lu, Jianhong; Liu, Yuliang; Liu, Wenbo; Liu, Xiaohong; Wrobel, Jay E.; Reitz, Allen B.; Dye, John M.; Harty, Ronald N.; Freedman, Bruce D.

    2015-01-01

    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 ...

  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. [Unexplained fever and B-symptoms in a young male Black African].

    Science.gov (United States)

    Weber, T; Ettrich, T; Christopeit, M; Lindner, A; Holzhausen, H J; Oehme, A; Arnold, D; Wolf, H H; Lübbert, C; Kekulé, A S; Schmoll, H J; Werdan, K; Ebelt, H

    2012-01-01

    An immunocompetent Nigerian developed a fulminant hemophagocytic lymphohistiocytosis due to Epstein-Barr virus reactivation. The patient initially presented with fever, hepatosplenomegaly and pancytopenia. The clinical status of our patient deteriorated quickly despite treatment with corticoids. Escalation of immunosuppressive treatment was not possible. He died of lung, liver and circulatory failure in our intensive care unit.Hemophagocytic lymphohistiocytosis is a rare disease characterized by inflammation due to prolonged and excessive activation of antigen-presenting cells. High plasma ferritin levels and phagocytosis of hematopoetic cells in bone marrow, spleen and liver lead to the diagnosis. Hemophagocytic lymphohistiocytosis should therefore be included in the differential diagnosis in patients with persistent fever, hepatosplenomegaly and cytopenia. PMID:21953027

  18. Overview of swine influenza virus vaccine research and technology: What's on the horizon and what do we need to move forward?

    Science.gov (United States)

    Introduction Swine influenza represents a problem for the health of pigs and the economic health of the swine industry due to real and perceived public health risks. This is largely driven by the diversity of influenza A viruses (IAV) in swine herds. Antigenic drift (mutations) and shifts (reassortm...

  19. Imported Lassa fever: a report of 2 cases in Ghana

    OpenAIRE

    Kyei, Nicholas N. A.; Abilba, Mark M.; Kwawu, Foster K.; Agbenohevi, Prince G; Bonney, Joseph H K; Agbemaple, Thomas K.; Nimo-Paintsil, Shirley C.; Ampofo, William; Ohene, Sally-Ann; Edward O. Nyarko

    2015-01-01

    Background Lassa fever is a potentially fatal acute viral illness caused by Lassa virus which is carried by rodents and is endemic in some West African countries. Importation of emerging infections such as Lassa fever, Ebola Virus Disease and other viral hemorrhagic fevers into non endemic regions is a growing threat particularly as international travel and commitments in resolving conflicts in endemic countries in the West Africa sub-region continue. Case presentation We report the first two...

  20. Haemaphysalis longicornis Ticks as Reservoir and Vector of Severe Fever with Thrombocytopenia Syndrome Virus in China

    OpenAIRE

    Luo, Li-Mei; Zhao, Li; Wen, Hong-Ling; Zhang, Zhen-Tang; Liu, Jian-Wei; Fang, Li-Zhu; Xue, Zai-Feng; Ma, Dong-Qiang; Zhang, Xiao-Shuang; Ding, Shu-Jun; Lei, Xiao-Ying; Yu, Xue-jie

    2015-01-01

    Severe fever with thrombocytopenia syndrome (SFTS) is an emerging hemorrhagic fever in East Asia caused by SFTS virus (SFTSV), a newly discovered phlebovirus. The Haemaphysalis longicornis tick has been suspected to be the vector of SFTSV. To determine whether SFTSV can be transmitted among ticks, from ticks to animals, and from animals to ticks, we conducted transmission studies between developmental stages of H. longicornis ticks and between ticks and mice. Using reverse transcription PCR, ...

  1. Yellow Fever Virus in Haemagogus leucocelaenus and Aedes serratus Mosquitoes, Southern Brazil, 2008

    OpenAIRE

    Cardoso, Jáder da C.; de Almeida, Marco A.B.; dos Santos, Edmilson; da Fonseca, Daltro F.; Sallum, Maria A.M.; Noll, Carlos A.; Monteiro, Hamilton A. de O.; Cruz, Ana C.R.; Carvalho, Valéria L.; Pinto, Eliana V.; Castro, Francisco C.; Neto, Joaquim P. Nunes; Segura, Maria N.O.; Vasconcelos, Pedro F.C.

    2010-01-01

    Yellow fever virus (YFV) was isolated from Haemagogus leucocelaenus mosquitoes during an epizootic in 2001 in the Rio Grande do Sul State in southern Brazil. In October 2008, a yellow fever outbreak was reported there, with nonhuman primate deaths and human cases. This latter outbreak led to intensification of surveillance measures for early detection of YFV and support for vaccination programs. We report entomologic surveillance in 2 municipalities that recorded nonhuman primate deaths. Mosq...

  2. Development and standardization of an indirect ELISA for the serological diagnosis of classical swine fever Desenvolvimento e padronização de um ELISA indireto para o diagnóstico sorológico de peste suína clássica

    Directory of Open Access Journals (Sweden)

    Julio Cesar Muñoz Paredes

    1999-07-01

    Full Text Available An indirect enzyme linked immunoassay (ELISA-I was developed and standardized for the serological diagnosis of classical swine fever (CSF. For the comparison, nine hundred and thirty-seven swine serum samples were tested by serum neutralization followed by immunoperoxidase staining (NPLA, considered as the standard. Of these, 223 were positive and 714 negative for neutralizing antibodies to classical swine fever virus (CSFV. In relation to the NPLA, the ELISA-I presented a 98.2% sensitivity; 92.86% specificity, 81.11% positive predictive value, 99.4% negative predictive value and a 94.1% precision. Statistical analysis showed a very strong correlation (r=0,94 between both tests. When compared to a commercially available ELISA kit, the performance of both, in relation to the NPLA, was similar. It was concluded that the ELISA-I is suitable for large scale screening of antibodies to classical swine fever virus, although it does not distinguish antibodies to classical swine fever virus from those induced by other pestiviruses.Um ensaio imunoenzimático do tipo ELISA indireto (ELISA-I foi desenvolvido e padronizado para o diagnóstico sorológico de peste suína clássica. Na comparação foram utilizadas novecentas e trinta e sete amostras de soros suínos, as quais foram testadas pelo teste de soroneutralização seguido de revelação por imunoperoxidase (NPLA, tomado como padrão, resultando em 223 amostras positivas e 714 negativas. Em relação ao NPLA, o ELISA-I apresentou sensibilidade de 98,21%, especificidade de 92,86%, valor preditivo positivo de 81,11%, valor preditivo negativo de 99,4% e precisão de 94,1%. A análise estatística dos resultados revelou uma correlação muito forte (r=0,94 entre os dois testes. Quando comparado com um "kit" de ELISA disponível comercialmente, a performance de ambos em relação ao NPLA foi similar. Concluiu-se que o ELISA-I é um teste apropriado para triagem em larga escala de soros para a detec

  3. Pandemic swine influenza virus (H1N1): A threatening evolution.

    Science.gov (United States)

    Khanna, Madhu; Kumar, Binod; Gupta, Neha; Kumar, Prashant; Gupta, Ankit; Vijayan, V K; Kaur, Harpreet

    2009-12-01

    "Survival of the fittest" is an old axiom laid down by the great evolutionist Charles Darwin and microorganisms seem to have exploited this statement to a great extent. The ability of viruses to adapt themselves to the changing environment has made it possible to inhabit itself in this vast world for the past millions of years. Experts are well versed with the fact that influenza viruses have the capability to trade genetic components from one to the other within animal and human population. In mid April 2009, the Centers for Disease Control and Prevention and the World Health Organization had recognized a dramatic increase in number of influenza cases. These current 2009 infections were found to be caused by a new strain of influenza type A H1N1 virus which is a re-assortment of several strains of influenza viruses commonly infecting human, avian, and swine population. This evolution is quite dependent on swine population which acts as a main reservoir for the reassortment event in virus. With the current rate of progress and the efforts of heath authorities worldwide, we have still not lost the race against fighting this virus. This article gives an insight to the probable source of origin and the evolutionary progress it has gone through that makes it a potential threat in the future, the current scenario and the possible measures that may be explored to further strengthen the war against pandemic. PMID:23100799

  4. Socioeconomic status and the prevalence of fever in children under age five: evidence from four sub-Saharan African countries

    Directory of Open Access Journals (Sweden)

    Novignon Jacob

    2012-07-01

    Full Text Available Abstract Background The burden of fevers remains enormous in sub-Saharan Africa. While several efforts at reducing the burden of fevers have been made at the macro level, the relationship between socioeconomic status and fever prevalence has been inconclusive at the household and individual levels. The purpose of this study was to examine how individual and household socioeconomic status influences the prevalence of fever among children under age five in four sub-Saharan African countries. Methods The study used data from the 2008 Demographic and Health Survey (DHS from Ghana, Nigeria, Kenya and Sierra Leone with a total of 38,990 children below age five. A multi-level random effects logistic model was fitted to examine the socioeconomic factors that influence the prevalence of fever in the two weeks preceding the survey. Data from the four countries were also combined to estimate this relationship, after country-specific analysis. Results The results show that children from wealthier households reported lower prevalence of fever in Ghana, Nigeria and Kenya. Result from the combined dataset shows that children from wealthier households were less likely to report fever. In general, vaccination against fever-related diseases and the use of improved toilet facility reduces fever prevalence. The use of bed nets by children and mothers did not show consistent relationship across the countries. Conclusion Poverty does not only influence prevalence of fever at the macro level as shown in other studies but also the individual and household levels. Policies directed towards preventing childhood fevers should take a close account of issues of poverty alleviation. There is also the need to ensure that prevention and treatment mechanisms directed towards fever related diseases (such as malaria, pneumonia, measles, diarrhoea, polio, tuberculosis etc. are accessible and effectively used.

  5. The hemorrhagic fevers of Southern Africa with special reference to studies in the South African Institute for Medical Research.

    OpenAIRE

    Gear, J H

    1982-01-01

    In this review of studies on the hemorrhagic fevers of Southern Africa carried out in the South African Institute for Medical Research, attention has been called to occurrence of meningococcal septicemia in recruits to the mining industry and South African Army, to cases of staphylococcal and streptococcal septicemia with hemorrhagic manifestations, and to the occurrence of plague which, in its septicemic form, may cause a hemorrhagic state. "Onyalai," a bleeding disease in tropical Africa, o...

  6. 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. PMID:22482712

  7. Presence of Viral RNA and Proteins in Exosomes from Cellular Clones Resistant to Rift Valley Fever Virus Infection

    OpenAIRE

    Ahsan, Noor A.; Sampey, Gavin C.; Lepene, Ben; Akpamagbo, Yao; Barclay, Robert A.; Iordanskiy, Sergey; Hakami, Ramin M.; KASHANCHI, FATAH

    2016-01-01

    Rift Valley Fever Virus (RVFV) is a RNA virus that belongs to the genus Phlebovirus, family Bunyaviridae. It infects humans and livestock and causes Rift Valley fever. RVFV is considered an agricultural pathogen by the USDA, as it can cause up to 100% abortion in cattle and extensive death of newborns. In addition, it is designated as Category A pathogen by the CDC and the NIAID. In some human cases of RVFV infection, the virus causes fever, ocular damage, liver damage, hemorrhagic fever, and...

  8. Quantitative analysis of particles, genomes and infectious particles in supernatants of haemorrhagic fever virus cell cultures

    Directory of Open Access Journals (Sweden)

    Hedlund Kjell-Olof

    2011-02-01

    Full Text Available Abstract Information on the replication of viral haemorrhagic fever viruses is not readily available and has never been analysed in a comparative approach. Here, we compared the cell culture growth characteristics of haemorrhagic fever viruses (HFV, of the Arenaviridae, Filoviridae, Bunyaviridae, and Flavivridae virus families by performing quantitative analysis of cell culture supernatants by (i electron microscopy for the quantification of virus particles, (ii quantitative real time PCR for the quantification of genomes, and (iii determination of focus forming units by coating fluorescent antibodies to infected cell monolayers for the quantification of virus infectivity. The comparative analysis revealed that filovirus and RVFV replication results in a surplus of genomes but varying degrees of packaging efficiency and infectious particles. More efficient replication and packaging was observed for Lassa virus, and Dengue virus resulting in a better yield of infectious particles while, YFV turned out to be most efficient with only 4 particles inducing one FFU. For Crimean-Congo haemorrhagic fever virus (CCHFV a surplus of empty shells was observed with only one in 24 particles equipped with a genome. The complete particles turned out to be extraordinarily infectious.

  9. Characterization of H1N1 Swine Influenza Viruses Circulating in Canadian Pigs in 2009▿

    OpenAIRE

    Nfon, Charles K.; Berhane, Yohannes; Hisanaga, Tamiko; Zhang, Shunzhen; Handel, Katherine; Kehler, Helen; Labrecque, Olivia; Lewis, Nicola S.; Vincent, Amy L.; Copps, John; Alexandersen, Soren; Pasick, John

    2011-01-01

    The 2009 pandemic H1N1 (pH1N1), of apparent swine origin, may have evolved in pigs unnoticed because of insufficient surveillance. Consequently, the need for surveillance of influenza viruses circulating in pigs has received added attention. In this study we characterized H1N1 viruses isolated from Canadian pigs in 2009. Isolates from May 2009 were comprised of hemagglutinin and neuraminidase (NA) genes of classical SIV origin in combination with the North American triple-reassortant internal...

  10. 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...

  11. Swine and rabbits are the main reservoirs of hepatitis E virus in China: detection of HEV RNA in feces of farmed and wild animals.

    Science.gov (United States)

    Xia, Junke; Zeng, Hang; Liu, Lin; Zhang, Yulin; Liu, Peng; Geng, Jiabao; Wang, Lin; Wang, Ling; Zhuang, Hui

    2015-11-01

    Hepatitis E virus (HEV) infection is recognized as a zoonosis. The prevalence of HEV RNA and anti-HEV antibodies in many animal species has been reported, but the host range of HEV is unclear. The aims of this study were to investigate HEV infection in various animal species and to determine the reservoirs of HEV. Eight hundred twenty-two fecal samples from 17 mammal species and 67 fecal samples from 24 avian species were collected in China and tested for HEV RNA by RT-nPCR. The products of PCR were sequenced and analyzed phylogenetically. The positive rates of HEV RNA isolated from pigs in Beijing, Shandong, and Henan were 33%, 30%, and 92%, respectively, and that from rabbits in Beijing was 5%. HEV RNA was not detectable in farmed foxes, sheep or sika deer, or in wild animals in zoos, including wild boars, yaks, camels, Asiatic black bears, African lions, red pandas, civets, wolves, jackals and primates. Sequence analysis revealed that swine isolates had 97.8%-98.4% nucleotide sequence identity to genotype 4d isolates from patients in Shandong and Jiangsu of China. Phylogenetic analysis showed that swine HEV isolates belong to genotype 4, including subgenotype 4h in Henan and 4d in Beijing and Shandong. The rabbit HEV strains shared 93%-99% nucleotide sequence identity with rabbit strains isolated from Inner Mongolia. In conclusion, swine and rabbits have been confirmed to be the main reservoirs of HEV in China. PMID:26303139

  12. 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 identified as T cell epitopes using fluorescent influenza: SLA tetramers. In addition, multiple CTL specificities were analyzed using peptide sequence substitutions in two of the four epitope candidates analyzed. Interestingly both conserved and substituted peptides were found to stain the CD...

  13. Sequence determination of the Crimean-Congo hemorrhagic fever virus L segment

    International Nuclear Information System (INIS)

    Crimean-Congo hemorrhagic fever (CCHF) virus is highly pathogenic for humans and remains the only Category A virus for which full sequence information is currently unavailable. In this study we completed CCHF genome characterization by determining the L segment sequence using Dugbe and CCHF virus-specific oligonucleotides. Sequence alignments revealed the presence of four previously described conserved regions in all Bunyaviridae polymerases. Interestingly, additional regions containing putative Ovarian Tumor (OTU)-like cysteine protease and helicase domains were identified in the L segments of CCHF and Dugbe viruses, suggesting an autoproteolytic cleavage process for nairovirus L proteins

  14. Isolation and identification of African horsesickness virus from naturally infected dogs in Upper Egypt.

    OpenAIRE

    Salama, S.A.; Dardiri, A. H.; Awad, F. I.; A. M. Soliman; M.M Amin

    1981-01-01

    African horsesickness virus was isolated from blood samples of street dogs in Aswan Province in Arab Republic of Egypt. Of six isolated "dog strain" African horsesickness viruses, three viruses designated D2, D6 and D10 have been identified as type 9 African horsesickness virus. Methods of isolation, tissue culture adaptation, serological indentification and typing are described. Horses experimentally infected with dog viruses showed febrile reaction and characteristic clinical and pathologic...

  15. 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.

  16. A recombinant Yellow Fever 17D vaccine expressing Lassa virus glycoproteins.

    Science.gov (United States)

    Bredenbeek, Peter J; Molenkamp, Richard; Spaan, Willy J M; Deubel, Vincent; Marianneau, Phillippe; Salvato, Maria S; Moshkoff, Dmitry; Zapata, Juan; Tikhonov, Ilia; Patterson, Jean; Carrion, Ricardo; Ticer, Anysha; Brasky, Kathleen; Lukashevich, Igor S

    2006-02-20

    The Yellow Fever Vaccine 17D (YFV17D) has been used as a vector for the Lassa virus glycoprotein precursor (LASV-GPC) resulting in construction of YFV17D/LASV-GPC recombinant virus. The virus was replication-competent and processed the LASV-GPC in cell cultures. The recombinant replicated poorly in guinea pigs but still elicited specific antibodies against LASV and YFV17D antigens. A single subcutaneous injection of the recombinant vaccine protected strain 13 guinea pigs against fatal Lassa Fever. This study demonstrates the potential to develop an YFV17D-based bivalent vaccine against two viruses that are endemic in the same area of Africa. PMID:16412488

  17. A recombinant Yellow Fever 17D vaccine expressing Lassa virus glycoproteins

    Science.gov (United States)

    Bredenbeek, Peter J.; Molenkamp, Richard; Spaan, Willy J.M.; Deubel, Vincent; Marianneau, Phillippe; Salvato, Maria S.; Moshkoff, Dmitry; Zapata, Juan; Tikhonov, Ilia; Patterson, Jean; Carrion, Ricardo; Ticer, Anysha; Brasky, Kathleen; Lukashevich, Igor S.

    2006-01-01

    The Yellow Fever Vaccine 17D (YFV17D) has been used as a vector for the Lassa virus glycoprotein precursor (LASV-GPC) resulting in construction of YFV17D/LASV-GPC recombinant virus. The virus was replication-competent and processed the LASV-GPC in cell cultures. The recombinant replicated poorly in guinea pigs but still elicited specific antibodies against LASV and YFV17D antigens. A single subcutaneous injection of the recombinant vaccine protected strain 13 guinea pigs against fatal Lassa Fever. This study demonstrates the potential to develop an YFV17D-based bivalent vaccine against two viruses that are endemic in the same area of Africa. PMID:16412488

  18. 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

    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....... 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...

  19. The costs of preventive activities for exotic contagious diseases-A Danish case study of foot and mouth disease and swine fever.

    Science.gov (United States)

    Denver, Sigrid; Alban, Lis; Boklund, Anette; Houe, Hans; Mortensen, Sten; Rattenborg, Erik; Tamstorf, Trine Vig; Zobbe, Henrik; Christensen, Tove

    2016-09-01

    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 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 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 in the analysis by assuming that the FMD/SF shares of costs as well as total costs for each activity could take on a most likely as well as a minimum and maximum value. A high degree of transparency was prioritized in the cost analysis, which enables reproducibility and easy access to conducting sensitivity analyses. A total of 27 FMD/SF preventive activities were identified. The estimated median (minimum-maximum) of total costs amounted to €32 (18-50) million in 2013. The single most costly FMD/SF related activity, amounting to €8 (5-13) million or 26% of total costs, was a national legal requirement to clean lorries immediately after transportation of live animals. The distribution of costs between stakeholders was estimated to be as follows: pig industry 63%, cattle industry 27%, and the public authorities 10%. Most of the activities focused on reducing the probability of spreading FMD/SF, while only a few activities were directed mainly towards reducing the probability of introduction. Legally required FMD/SF activities (mainly based on EU legislation) accounted

  20. On the Mathematical Analysis of Ebola Hemorrhagic Fever: Deathly Infection Disease in West African Countries

    Directory of Open Access Journals (Sweden)

    Abdon Atangana

    2014-01-01

    Full Text Available For a given West African country, we constructed a model describing the spread of the deathly disease called Ebola hemorrhagic fever. The model was first constructed using the classical derivative and then converted to the generalized version using the beta-derivative. We studied in detail the endemic equilibrium points and provided the Eigen values associated using the Jacobian method. We furthered our investigation by solving the model numerically using an iteration method. The simulations were done in terms of time and beta. The study showed that, for small portion of infected individuals, the whole country could die out in a very short period of time in case there is not good prevention.