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Sample records for classical swine fever

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

    Science.gov (United States)

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

  2. 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......

  3. 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.

  4. Vaccinology of classical swine fever: from lab to field

    NARCIS (Netherlands)

    Oirschot, van J.T.

    2003-01-01

    There are two types of classical swine fever vaccines available: the classical live and the recently developed E2 subunit vaccines. The live Chinese strain vaccine is the most widely used. After a single vaccination, it confers solid immunity within a few days that appears to persist lifelong. The E

  5. 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...

  6. 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...

  7. 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.

  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. 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...

  10. 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...

  11. 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 antic......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...... as free antibodies were not detected in serum even though the sows had Virus neutralization titer (Vnt) titers of 100. Non-PI piglets were able to raise active immunity, since specific antibodies to CSFV stabilized at a mean Vnt titer of 200. While some PI piglets showed growth retardation as well...

  12. 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

  13. 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...

  14. Modeling Classical Swine Fever Outbreak-Related Outcomes

    OpenAIRE

    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 (...

  15. Modeling classical swine fever outbreak-related outcomes

    OpenAIRE

    Shankar eYadav; Olynk Widmar, Nicole J.; HSIN-YI eWENG

    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. 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...

  16. 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...

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

    Science.gov (United States)

    Controlling classical swine fever (CSF) involves vaccination in endemic regions and preemptive slaughter of infected swine herds during epidemics. Generally, live attenuated vaccines induce solid immunity. Using diverse approaches, reverse genetics has been useful in developing classical swine fever...

  18. 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.

  19. 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

  20. 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.

  1. 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...

  2. 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...

  3. 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.

  4. 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...

  5. 9 CFR 94.9 - Pork and pork products from regions where classical swine fever exists.

    Science.gov (United States)

    2010-01-01

    ... FEVER, CLASSICAL SWINE FEVER, SWINE VESICULAR DISEASE, AND BOVINE SPONGIFORM ENCEPHALOPATHY: PROHIBITED... the region of origin, and (B) The meat has been held in an unfrozen, fresh condition for at least 3 days immediately following the slaughter of the animals from which it was derived, and (C) The meat...

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

    Science.gov (United States)

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

    2014-06-01

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

  7. 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 ...

  8. 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.

  9. Economic welfare analysis of simulated control strategies for classical swine fever epidemics

    OpenAIRE

    Mangen, M.J.J.

    2002-01-01

     Keywords: Classical swine fever; contagious disease; epidemiological model; sector-level market and trade model; simulation; economic welfare analysis; densely and sparsely populated areas; supplementary animal welfare measures; the Netherlands. A sector-level and trade market model and a generic, spatial, temporal and stochastic epidemiological model are used to simulate the epidemiological and economic effects of different measures to control classical swine fever (CSF) epidemics in differ...

  10. 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 ...

  11. 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....

  12. 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.

  13. 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.

  14. The control of classical swine fever in wild boar.

    Science.gov (United States)

    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 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 R 0 < 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. PMID:26594202

  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. 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...

  18. 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...

  19. 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

  20. 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

  1. 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...

  2. 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.......3 strains, there is very little information available on longer fragments or whole classical swine fever virus (CSFV) genomes. Furthermore, there are no detailed analyses of the molecular epidemiology of CSFV wild boar isolates available. Nevertheless, complete genome sequences are supportive...

  3. 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

    Two commercial marker vaccines against classical swine fever virus (CSFV) and companion diagnostic tests were examined in 160 conventional pigs. To test the vaccines in a "worst case scenario", group of 10 weaners were vaccinated using a single dose of an E2 (gp55) based vaccine at days -21, -14......, -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...

  4. 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.

  5. Comparison of PCR methods for detection of classical swine fever virus and other pestiviruses.

    Science.gov (United States)

    Podgórska, K; Kamieniecka, K; Stadejek, T; Pejsak, Z

    2012-01-01

    Classical swine fever (CSF) is a notifiable, highly contagious disease of swine controlled mainly with costly administrative methods. Swine may be infected not only with classical swine fever virus (CSFV), but also with other, non porcine, genetically and antigenically related pestiviruses. Differentiation of infections with CSFV and other pestiviruses is a crucial element of diagnostics. In the present study two real-time PCR methods and conventional one-tube nested PCR for specific detection of CSFV were compared. Additionally, two methods designed for detection of all pestivirus species real-time SYBR Green I and one-tube nested PCR were included into the study. Analyzed methods varied considerably regarding their sensitivity and specificity, what suggests that careful selection of diagnostic methods and their evaluation on a regular basis is necessary.

  6. 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 ...

  7. 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...

  8. 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...

  9. 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

  10. Laboratory diagnosis, epizootiology and efficacy of marker vaccines in classical swine fever: a review

    NARCIS (Netherlands)

    Smit, de A.J.

    2000-01-01

    Detection of classical swine fever virus (CSFV) can be achieved by a range of assays of which the most commonly used are: immunohistochemical and virus culture techniques. New developments have enabled the detection of viral proteins by enzyme-linked immunosorbent assays (ELISAs) and the detection o

  11. Economic welfare analysis of simulated control strategies for classical swine fever epidemics

    NARCIS (Netherlands)

    Mangen, M.J.J.

    2002-01-01

     Keywords: Classical swine fever; contagious disease; epidemiological model; sector-level market and trade model; simulation; economic welfare analysis; densely and sparsely populated areas; supplementary animal welfare measure

  12. 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

  13. Who gains, who loses? Welfare effects of classical swine fever epidemics in the Netherlands

    NARCIS (Netherlands)

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

    2003-01-01

    A sectoral market model and a stochastic epidemiological model were used to simulate the effects of classical swine fever (CSF) epidemics in the Netherlands in 1997-1998. Compulsory EU control measures were implemented. Welfare changes of Dutch stakeholders, as well as government costs, were calcula

  14. 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.

  15. 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.

  16. 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...

  17. 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...

  18. 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...

  19. 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...

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

    NARCIS (Netherlands)

    Bergevoet, R.H.M.; Asseldonk, van M.A.P.M.; 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 imp

  1. C-strain vaccination against Classical Swine Fever: effects on epidemic and final screening

    NARCIS (Netherlands)

    Backer, J.A.; Loeffen, W.L.A.; Roermund, van H.J.W.

    2013-01-01

    In this project it is evaluated how the use of C-strain vaccine instead of E2-subunit vaccine will affect the effectiveness of controlling Classical Swine Fever (CSF). To this end a CSF transmission model was developed that describes virus transmission on three different levels: between animals, bet

  2. 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...

  3. Modeling and Real-Time Prediction of Classical Swine Fever Epidemics

    NARCIS (Netherlands)

    Meester, R.; Koning, de J.; Jong, de M.C.M.; Diekmann, O.

    2002-01-01

    We propose a new method to analyze outbreak data of an infectious disease such as classical swine fever. The underlying model is a two-type branching process. It is used to deduce information concerning the epidemic from detected cases. In particular, the method leads to prediction of the future cou

  4. Cost-effectiveness of measures to prevent classical swine fever introduction into The Netherlands

    NARCIS (Netherlands)

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

    2005-01-01

    Recent history has demonstrated that classical swine fever (CSF) epidemics can incur high economic losses, especially for exporting countries that have densely populated pig areas and apply a strategy of non-vaccination, such as The Netherlands. Introduction of CSF virus (CSFV) remains a continuing

  5. 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.

  6. 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。

  7. 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...

  8. 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

  9. 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

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

    Science.gov (United States)

    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 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. PMID:26664939

  11. 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

  12. 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.

  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

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

  14. 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...

  15. 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...

  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. 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...

  18. 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.

  19. 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.

  20. Classical swine fever virus replicated poorly in cells from MxA transgenic pigs

    OpenAIRE

    Zhao, Yicheng; Wang, Tiedong; Yao, Li; Liu, Bo; Teng, Chunbo; Ouyang, Hongsheng

    2016-01-01

    Background In addition to their value as livestock, pigs are susceptible to classical swine fever virus (CSFV) and can serve as reservoirs for CSFV, allowing it to develop into an epizootic. CSFV, a pestivirus of the Flaviviridae family, has a single-stranded RNA genome. Recent research has indicated that the human MxA protein inhibits the life cycles of certain RNA viruses, such as members of the Bunyaviridae family, the Flaviviridae family and others. Results To produce pigs with antiviral ...

  1. 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

  2. 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...

  3. 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.

  4. 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

  5. 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.

  6. 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...

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

    DEFF Research Database (Denmark)

    Boklund, Anette; Toft, Nils; Alban, Lis;

    2009-01-01

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

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

    DEFF Research Database (Denmark)

    Boklund, Anette; Toft, Nils; Alban, Lis;

    2009-01-01

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

  9. 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

    2015-07-09

    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.

  10. 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

  11. Characterization of cytopathogenicity of classical swine fever virus isolate induced by Newcastle disease virus.

    Science.gov (United States)

    Raut, S D; Rajak, K K; Kumar, R; Singh, V K; Saxena, A; Chaudhary, D; Muthuchelvan, D; Pandey, A B

    2015-06-01

    Classical swine fever virus (CSFV), the causative agent of classical swine fever, belongs to the family Flaviviridae and genus Pestivirus. Some pestiviruses exhibit cytopathic effect in cell culture but exact phenomenon is unknown. Over expression of NS2-3 gene, presence of defective interfering particle and exaltation of Newcastle disease virus (END) phenomenon could be the reasons of cytopathogenicity. In the present study, a CSFV isolate exhibiting cytopathic effect (CPE) in Madin-Darby Canine Kidney (MDCK) cell line was characterized. To characterize cytopathogenicity of such isolate, END test was carried out. Interference of Newcastle disease virus (NDV) in MDCK adapted CSFV was confirmed by RT-PCR and virus neutralization test. Absence of CPE and NDV specific nucleic acid after neutralization confirmed the induction of CPE by NDV. Further, identity of the CSFV isolate in MDCK cell line by immunoperoxidase test, immunoblotting and RT-PCR post NDV neutralization established the virus replication without CPE (non-cytopathic isolate). Findings suggest that, there could be a chance of mixed infection of both CSFV and NDV in the piglet from which the sample was collected for virus isolation. PMID:26436124

  12. 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

  13. 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.

  14. 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

  15. 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...

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

    Science.gov (United States)

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

    2014-01-01

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

  17. 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

  18. 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.

  19. 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.

  20. Detection and quantification of classical swine fever virus in air samples originating from infected pigs and experimentally produced aerosols

    NARCIS (Netherlands)

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

    2008-01-01

    During epidemics of classical swine fever (CSF), neighbourhood infections occurred where none of the 'traditional' routes of transmission like direct animal contact, swill feeding, transport contact or transmission by people could be identified. A hypothesized route of virus introduction for these h

  1. 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...

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

    NARCIS (Netherlands)

    Boender, G.J.; Nodelijk, G.; Hagenaars, T.H.J.; Elbers, A.R.W.; Jong, de M.C.M.

    2008-01-01

    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 th

  3. 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 mode...

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

    NARCIS (Netherlands)

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

    2008-01-01

    Indirect transmission of classical swine fever virus (CSFV) can occur through contact with mechanical vectors, like clothing and footwear or transport vehicles, contaminated with the secretions or excretions of infected pigs. A prerequisite for indirect transmission is survival of the virus on the m

  5. 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 ...

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    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...

  7. 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...

  8. 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

  9. 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.

  10. Disseminated intravascular coagulation does not play a major role in the pathogenesis of classical swine fever.

    Science.gov (United States)

    Blome, Sandra; Meindl-Böhmer, Alexandra; Nowak, Götz; Moennig, Volker

    2013-03-23

    Classical swine fever (CSF) is a multi-systemic disease that can be accompanied by severe haemorrhagic lesions. The underlying pathogenetic mechanisms are still far from being understood, though disseminated intravascular coagulation (DIC) was discussed as a major factor. In the presented study, the direct thrombin inhibitor hirudin was used in an attempt to elucidate the role of the coagulation system in the pathogenesis of CSF-induced haemorrhagic lesions. Two groups of piglets (n=5) were infected with highly virulent CSF virus (CSFV) strain CSF0634. One group underwent daily treatment with hirudin, the other served as untreated challenge infection control. Assessment of clinical signs using a clinical score system, coagulation tests, and blood counts were performed daily. Both groups developed acute-lethal CSF with haemorrhagic lesions. Although changes in the coagulation system were seen in the late stages of CSFV infection, our results strongly suggest that DIC does not present the crucial event in the pathogenesis of haemorrhagic lesions.

  11. 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

    before real-time reverse transcription polymerase chain reaction analysis was performed. Viral RNA was detected in meat juice, but at a lower level than in corresponding serum. Sensitivity was calculated to 91% and specificity to 97%. Disagreements between meat juice and serum results were found when......To evaluate the diagnostic potential of meat juice for early detection of Classical swine fever virus (CSFV), meat juice and serum samples from pigs experimentally infected with different strains of CSFV were compared for virus load. From all samples, viral RNA was extracted by automated procedure...... samples originated from pigs infected with low virulence CSFV strains and/or when samples were collected within the first days after infection. In conclusion, while not the first choice for sample material for CSFV diagnosis, meat juice may constitute a useful alternative for herd-based studies or when...

  12. Studying classical swine fever virus: making the best of a bad virus.

    Science.gov (United States)

    Ji, Wei; Guo, Zhen; Ding, Nai-Zheng; He, Cheng-Qiang

    2015-02-01

    Classical swine fever (CSF) is a highly contagious and often fatal disease that affects domestic pigs and wild boars. Outbreak of CSF can cause heavy economic losses to the pig industry. The strategies to prevent, control and eradicate CSF disease are based on containing the disease through a systematic prophylactic vaccination policy and a non-vaccination stamping-out policy. The quest for prevention, control and eradication of CSF has moved research forward in academia and industry, and has produced noticeable advances in understanding fundamental aspects of the virus replication mechanisms, virulence, and led to the development of new vaccines. In this review we summarize recent progress in CSFV epidemiology, molecular features of the genome and proteome, the molecular basis of virulence, and the development of anti-virus technologies.

  13. 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

  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. 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

  16. 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.

  17. 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

  18. Virus load in pigs affected with different clinical forms of classical swine fever.

    Science.gov (United States)

    Rout, M; Saikumar, G

    2012-04-01

    Classical swine fever (CSF) is an endemic disease in India, but the real magnitude of the problem is not known as only outbreaks of acute CSF are reported and many cases of chronic and clinically inapparent forms of the disease, which manifest a confusing clinical picture, remain undiagnosed. The real status of classical swine fever virus (CSFV) infection can only be known by testing pigs with highly specific and sensitive diagnostic assays. To obtain the baseline prevalence of CSFV infection among pigs in an endemic region where no vaccination was being performed, a real-time PCR assay was used to detect viral genetic material in tissue samples collected from a slaughterhouse in the northern state of Uttar Pradesh in India. In total, 1120 slaughtered pigs were examined for the presence of CSF suggestive pathological lesions and tissues from suspected cases were tested for the presence of CSFV antigen and nucleic acids by indirect immuno-peroxidase test and real-time PCR, respectively. Based on the detection of viral genetic material in the tonsils, the prevalence of CSFV infection among slaughtered pigs was found to be 7.67%. Pigs detected positive for viral genome by quantitative real-time PCR assay when categorized into different forms of CSF, depending upon the pathological lesions observed, the viral load in the tonsils of some of the pigs with chronic or clinically inapparent form of the disease was similar to that detected in pigs with acute CSF. The results of the study suggested that the risk posed by pigs with chronic disease or those infected but showing no clinical disease may be relatively higher as they can transmit the virus to new susceptible hosts over a longer period of time.

  19. 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.

  20. The core protein of classical Swine Fever virus is dispensable for virus propagation in vitro.

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    Christiane Riedel

    Full Text Available Core protein of Flaviviridae is regarded as essential factor for nucleocapsid formation. Yet, core protein is not encoded by all isolates (GBV- A and GBV- C. Pestiviruses are a genus within the family Flaviviridae that affect cloven-hoofed animals, causing economically important diseases like classical swine fever (CSF and bovine viral diarrhea (BVD. Recent findings describe the ability of NS3 of classical swine fever virus (CSFV to compensate for disabling size increase of core protein (Riedel et al., 2010. NS3 is a nonstructural protein possessing protease, helicase and NTPase activity and a key player in virus replication. A role of NS3 in particle morphogenesis has also been described for other members of the Flaviviridae (Patkar et al., 2008; Ma et al., 2008. These findings raise questions about the necessity and function of core protein and the role of NS3 in particle assembly. A reverse genetic system for CSFV was employed to generate poorly growing CSFVs by modification of the core gene. After passaging, rescued viruses had acquired single amino acid substitutions (SAAS within NS3 helicase subdomain 3. Upon introduction of these SAAS in a nonviable CSFV with deletion of almost the entire core gene (Vp447(Δc, virus could be rescued. Further characterization of this virus with regard to its physical properties, morphology and behavior in cell culture did not reveal major differences between wildtype (Vp447 and Vp447(Δc. Upon infection of the natural host, Vp447(Δc was attenuated. Hence we conclude that core protein is not essential for particle assembly of a core-encoding member of the Flaviviridae, but important for its virulence. This raises questions about capsid structure and necessity, the role of NS3 in particle assembly and the function of core protein in general.

  1. Classical Swine Fever in Wild Hog: Report of its Prevalence in Northeast India.

    Science.gov (United States)

    Barman, N N; Bora, D P; Khatoon, E; Mandal, S; Rakshit, A; Rajbongshi, G; Depner, K; Chakraborty, A; Kumar, S

    2016-10-01

    Classical swine fever virus (CSFV) is the causative agent of a highly contagious disease, hog cholera in pigs. The disease is endemic in many parts of the world and vaccination is the only way to protect the animals from CSFV infection. Wild hogs belong to the species Sus Scrofa Cristatus under the family Suidae are quite susceptible to CSFV infection. The epidemiological role concerning classical swine fever (CSF) in India is largely unknown. We report here the three isolated cases of CSF in wild hogs from three National parks, namely Kaziranga National Park, Manas National Park and Jaldapara National Park, from north-east part of India. The post-mortem and histopathological findings were clearly indicative for CSFV infection. The presence of CSFV genome was demonstrated in several organs and tissues collected from hogs died due to viral infection. In addition, CSF-specific antibodies were detected in two wild hogs as well as in eighteen feral pigs from the same locations. The phylogenetic analysis of the partial E2 protein gene and 5' untranslated region of CSFV isolates from the wild hog showed identities with genotype 2.2 of the Indian isolates. Occurrence of CSF in wild hogs may pose a potent threat in the epidemiology of the virus in Northeast part of India. To the best of our knowledge, the report presented in the manuscript is the first comprehensive report on CSF in wild hogs form Northeast India. The findings reported would help us to understand the epidemiology and biology of CSFV in wild animals. PMID:25430917

  2. 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 ...

  3. 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...

  4. 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...

  5. 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.

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

    Science.gov (United States)

    Zhao, T S; Xia, Y H

    2016-06-01

    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 E(rns) 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

  7. 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.

  8. Insulated Isothermal Reverse Transcriptase PCR (iiRT-PCR) for Rapid and Sensitive Detection of Classical Swine Fever Virus.

    Science.gov (United States)

    Lung, O; Pasick, J; Fisher, M; Buchanan, C; Erickson, A; Ambagala, A

    2016-10-01

    Classical swine fever (CSF) is an OIE-listed disease that can have a severe impact on the swine industry. User-friendly, sensitive, rapid diagnostic tests that utilize low-cost field-deployable instruments for CSF diagnosis can be useful for disease surveillance and outbreak monitoring. In this study, we describe validation of a new probe-based insulated isothermal reverse transcriptase PCR (iiRT-PCR) assay for rapid detection of classical swine fever virus (CSFV) on a compact, user-friendly device (POCKIT(™) Nucleic Acid Analyzer) that does not need data interpretation by the user. The assay accurately detected CSFV RNA from a diverse panel of 33 CSFV strains representing all three genotypes plus an additional in vitro-transcribed RNA from cloned sequences representing a vaccine strain. No cross-reactivity was observed with a panel of 18 viruses associated with livestock including eight other pestivirus strains (bovine viral diarrhoea virus type 1 and type 2, border disease virus, HoBi atypical pestivirus), African swine fever virus, swine vesicular disease virus, swine influenza virus, porcine respiratory and reproductive syndrome virus, porcine circovirus 1, porcine circovirus 2, porcine respiratory coronavirus, vesicular exanthema of swine virus, bovine herpes virus type 1 and vesicular stomatitis virus. The iiRT-PCR assay accurately detected CSFV as early as 2 days post-inoculation in RNA extracted from serum samples of experimentally infected pigs, before appearance of clinical signs. The limit of detection (LOD95% ) calculated by probit regression analysis was 23 copies per reaction. The assay has a sample to answer turnaround time of less than an hour using extracted RNA or diluted or low volume of neat serum. The user-friendly, compact device that automatically analyses and displays results could potentially be a useful tool for surveillance and monitoring of CSF in a disease outbreak. PMID:25644051

  9. 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

  10. Evaluation of specific humoral immune response in pigs vaccinated with cell culture adapted classical swine fever vaccine

    OpenAIRE

    Nath, Mrinal K.; Sarma, D. K.; B. C. DAS; Deka, P.; Kalita, D.; Dutta, J. B.; Mahato, G.; S Sarma; Roychoudhury, P

    2016-01-01

    Aim: To determine an efficient vaccination schedule on the basis of the humoral immune response of cell culture adapted live classical swine fever virus (CSFV) vaccinated pigs and maternally derived antibody (MDA) in piglets of vaccinated sows. Materials and Methods: A cell culture adapted live CSFV vaccine was subjected to different vaccination schedule in the present study. Serum samples were collected before vaccination (day 0) and 7, 14, 28, 42, 56, 180, 194, 208, 270, 284 and 298 days af...

  11. 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...

  12. 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.

  13. 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

  14. Prevalence of classical swine fever virus in domestic pigs in South Korea: 1999-2011.

    Science.gov (United States)

    Song, J-Y; Lim, S I; Jeoung, H Y; Choi, E-J; Hyun, B-H; Kim, B; Kim, J; Shin, Y-K; Dela Pena, R C; Kim, J B; Joo, H; An, D J

    2013-12-01

    The major policy for eradication of classical swine fever (CSF) in South Korea has focused on the implementation of compulsory vaccination of the susceptible pig population. A vaccine strain of CSF virus, the LOM strain, is used to maintain high herd seroconversion, a practice complementary to the 'stamping-out policy' and restriction of animal movement during disease outbreaks. To survey for the prevalence of CSF in domestic pigs in South Korea over the past 13 years (1999-2011), we tested 4 193 782 and 1 162 645 samples for antibodies and antigens, respectively. Whereas seropositivity for CSF antibodies has been maintained at over 95% in the mainland, in Jeju Island, where no-vaccination has been administered since 1999, seroprevalence has been below 1% during the last 3 years of study (2009-2011). The highest number of outbreaks in South Korea occurred in 2002 and 2003; since then, outbreaks have decreased each year, with the last CSF outbreak recorded in 2009. No outbreaks have occurred during the past 3 years, and a high level of herd immunity has been maintained in the mainland pig population for 8 years; therefore, South Korea could now switch to a no-vaccination policy throughout the country. However, the constant threat of the re-emergence of the disease in the susceptible pig population should be the main consideration in planning and carrying out the last phase of the CSF eradication process.

  15. 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

  16. 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.

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

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    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.

  18. 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

  19. 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.

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

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    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.

  1. 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

  2. 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

  3. 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

  4. 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

  5. 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.

  6. 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

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

    Science.gov (United States)

    Lohse, Louise; Nielsen, Jens; Uttenthal, Ase

    2012-10-12

    Host-virus interactions play an important role for the clinical outcome of classical swine fever virus (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 experimental set-up, reducing the influence of host and environmental factors. Thus, weaner pigs were inoculated with one of 4 CSFV strains in order to compare the pathogenesis for a 3-week-period after infection. CSFV strains selected were 2 new and 2 previously characterized. None of these strains had been tested in Danish outbred pigs before. Clinical observations grouped the infected pigs into two different categories reflecting either non-specific, mainly gastro-intestinal, problems, or severe disease including high fever within the first week after inoculation. Gross-pathological findings varied between strains, however, lymphoid atrophy and growth retardation represented a consistent finding for all 4 strains. Virus distribution, viral load and in particular virus persistence differed, but supported present practice that recommends lymphoid tissue, most optimal tonsil and lymph nodes, as target material to be applied for early laboratory diagnosis. The present study demonstrated constraints associated with early detection of infections with CSFV strains of low virulence. Since neither clinical symptoms nor pathological lesions observed with these strains constituted characteristic signs of CSF, the risk of neglecting a CSF suspicion is immediate. Therefore, topical information on new outbreaks and continuous enhancement of an efficient surveillance system is of great importance to prevent further spread of CSF within the pig population.

  8. 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.

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

    DEFF Research Database (Denmark)

    Bøtner, Anette; Belsham, Graham

    2012-01-01

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

  10. [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

  11. Identification and characterization of mimotopes of classical swine fever virus E2 glycoprotein using specific anti-E2 monoclonal antibodies

    NARCIS (Netherlands)

    Batonick, M.; Loeffen, W.L.A.; Metwally, S.A.; Mayr, G.A.

    2013-01-01

    Classical swine fever virus (CSFV) shares high nucleic acid and amino acid sequence homology with the other members of the pestivirus genus, namely bovine viral diarrhea virus and border disease virus. All three viruses are able to infect swine and generate cross reactive antibodies, which is proble

  12. A common neutralizing epitope on envelope glycoprotein E2 of different pestiviruses: Implications for improvement of vaccines and diagnostics for classical swine fever (CSF)?

    NARCIS (Netherlands)

    Rijn, van P.A.

    2007-01-01

    The Pestivirus genus within the family of Flaviviridae consists of at least three species; classical swine fever virus (CSFV) found in swine and wild boar, bovine viral diarrhoea virus type 1 and type 2 (BVDV-I and BVDV-II) mainly isolated from cattle and border disease virus (BDV) preferably replic

  13. 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

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

    Science.gov (United States)

    Muñoz-González, Sara; Ruggli, Nicolas; Rosell, Rosa; Pérez, Lester Josué; Frías-Leuporeau, Maria Teresa; Fraile, Lorenzo; Montoya, Maria; Cordoba, Lorena; Domingo, Mariano; Ehrensperger, Felix; Summerfield, Artur; Ganges, Llilianne

    2015-01-01

    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 might go unnoticed

  15. Genetic diversity and positive selection analysis of classical swine fever virus isolates in south China.

    Science.gov (United States)

    Shen, Haiyan; Pei, Jingjing; Bai, Jialin; Zhao, Mingqiu; Ju, Chunmei; Yi, Lin; Kang, Yanmei; Zhang, Xuetao; Chen, Lijun; Li, Yinguang; Wang, Jiaying; Chen, Jinding

    2011-10-01

    Classical swine fever virus (CSFV) causes a highly contagious disease that leads to significant economic losses in the pig industry worldwide. However, there is a paucity of knowledge on the accurate genotyping of CSFV isolates in south China. This study genotyped the E2 gene of 14 CSFV strains isolated during 2008-2010 from domestic pigs in different districts of south China. Phylogenetic analyses revealed that all of the 14 CSFV isolates were clustered into genetic subgroup 1.1. This contrasts with most parts of China, where group 2 isolates are predominant. Furthermore, the positive selection pressures acting on the E(rns) and E2 envelope protein genes of CSFV were assessed and a site-by-site analysis of the dN/dS ratio was performed to identify specific codons that undergo diversification under positive selection. While no significant evidence for positive selection was observed in E(rns), two positively selected sites at amino acid residues 49 and 72 in the E2 encoding region were identified. Our results revealed that a predominance of subgroup 1.1 CSFV isolates is currently circulating in some districts of south China, which appear to be unrelated to the Chinese C-strain vaccine. Moreover, the envelope protein gene, E2, has undergone positive selection in 14 CSFV strains and two positively selected sites have been identified in this study. Understanding the molecular epidemiology and functional importance of these positively selected amino acid positions could help to predict possible changes in virulence, the development of vaccines and disease control.

  16. Genetic diversity and positive selection analysis of classical swine fever virus isolates in south China.

    Science.gov (United States)

    Shen, Haiyan; Pei, Jingjing; Bai, Jialin; Zhao, Mingqiu; Ju, Chunmei; Yi, Lin; Kang, Yanmei; Zhang, Xuetao; Chen, Lijun; Li, Yinguang; Wang, Jiaying; Chen, Jinding

    2011-10-01

    Classical swine fever virus (CSFV) causes a highly contagious disease that leads to significant economic losses in the pig industry worldwide. However, there is a paucity of knowledge on the accurate genotyping of CSFV isolates in south China. This study genotyped the E2 gene of 14 CSFV strains isolated during 2008-2010 from domestic pigs in different districts of south China. Phylogenetic analyses revealed that all of the 14 CSFV isolates were clustered into genetic subgroup 1.1. This contrasts with most parts of China, where group 2 isolates are predominant. Furthermore, the positive selection pressures acting on the E(rns) and E2 envelope protein genes of CSFV were assessed and a site-by-site analysis of the dN/dS ratio was performed to identify specific codons that undergo diversification under positive selection. While no significant evidence for positive selection was observed in E(rns), two positively selected sites at amino acid residues 49 and 72 in the E2 encoding region were identified. Our results revealed that a predominance of subgroup 1.1 CSFV isolates is currently circulating in some districts of south China, which appear to be unrelated to the Chinese C-strain vaccine. Moreover, the envelope protein gene, E2, has undergone positive selection in 14 CSFV strains and two positively selected sites have been identified in this study. Understanding the molecular epidemiology and functional importance of these positively selected amino acid positions could help to predict possible changes in virulence, the development of vaccines and disease control. PMID:21643769

  17. 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

  18. 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.

  19. 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

  20. A multiplex PCR for simultaneous detection of classical swine fever virus, African swine fever virus, highly pathogenic porcine reproductive and respiratory syndrome virus, porcine reproductive and respiratory syndrome virus and pseudorabies in swines.

    Science.gov (United States)

    Hu, L; Lin, X Y; Yang, Z X; Yao, X P; Li, G L; Peng, S Z; Wang, Y

    2015-01-01

    In this assay, we developed and evaluated a multiplex PCR (mPCR) for its ability in detecting multiple infections of swine simultaneously. Four pairs of primers were used to detect five viruses. Specific primers were designed for classical swine fever virus (CSFV), African swine fever virus (ASFV) and pseudorabies (PRV). A pair of primers was designed prudently for two different types of porcine reproductive and respiratory syndrome virus that respectively were porcine reproductive and respiratory syndrome virus (PRRSV), highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV). The detection limits of the mPCR were 1.09 × 10⁴, 1.50 × 10³, 2.10 × 10³, 1.30 × 10³ and 8.97 × 10² copies/reaction for CSFV, ASFV, HP-PRRSV, PRRSV and PRV, respectively. A total of 49 clinical specimens were tested by the mPCR, and the result showed that co-infection by two or three viruses was 51%. In conclusion, the PCR is a useful tool for clinical diagnosis of not only single infections but also mixed infections in swines. PMID:26812812

  1. The classical swine fever epidemic 1997-1998 in The Netherlands: descriptive epidemiology.

    Science.gov (United States)

    Elber, A R; Stegeman, A; Moser, H; Ekker, H M; Smak, J A; Pluimers, F H

    1999-12-01

    The objective of this paper is to describe the severe epidemic of classical swine fever (CSF) in The Netherlands in 1997-1998 under a policy of non-vaccination, intensive surveillance, pre-emptive slaughter and stamping out in an area which has one of the highest pig and herd densities in Europe. The primary outbreak was detected on 4 February 1997 on a mixed sow and finishing pig herd. A total of 429 outbreaks was observed during the epidemic, and approximately 700,000 pigs from these herds were slaughtered. Among these outbreaks were two artificial insemination centres, which resulted in a CSF-suspect declaration of 1680 pig herds (mainly located in the southern part of The Netherlands). The time between introduction of CSF virus (CSFV) into the country and diagnosis of CSF in the primary outbreak was estimated to be approximately 6 weeks. It is presumed that CSFV was spread from The Netherlands to Italy and Spain via shipment of infected piglets in the beginning of February 1997, before the establishment of a total stand-still of transportation. In June 1997, CSFV is presumed to be introduced into Belgium from The Netherlands. Pre-emptive slaughter of herds that had been in contact with infected herds or were located in close vicinity of infected herds, was carried out around the first two outbreaks. However, this policy was not further exercised till mid-April 1997, when pre-emptive slaughter became a standard operational procedure for the rest of the epidemic. In total, 1286 pig herds were pre-emptively slaughtered. (approximately 1.1 million pigs). A total of 44 outbreaks (10%) was detected via pre-emptive slaughter. When there were clinical signs, the observed symptoms in infected herds were mainly atypical: fever, apathy, ataxia or a combination of these signs. In 322 out of 429 outbreaks (75%), detection was bases on clinical signs observed: 32% was detected by the farmer, 25% by the veterinary practitioner, 10% of the outbreaks by tracing teams and 8% by

  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. Some epidemio-clinico-pathological aspects of an outbreak of classical swine fever in a desert district from Rajasthan (India

    Directory of Open Access Journals (Sweden)

    Anil K. Kataria

    2010-12-01

    Full Text Available In summer of 2009 an outbreak of classical swine fever was recorded in Sahwa village,district Churu (Rajasthan, leading to death of about 80 pigs. The disease started after 3 weeks ofintroduction of new piglets in the population and it affected initially young ones and then adult pigs.Only exotic crossbred pigs succumbed, while indigenous breed was not affected. The outbreak wasdiagnosed on the basis of epidemiology, typical clinical signs and post-mortem lesions, and laterconfirmed by laboratory tests. The disease was controlled by observing hygienic measures, propercarcass disposal, restricting the movement of pigs and by vaccinating the healthy pig population awayfrom the epicenter of outbreak.

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

    DEFF Research Database (Denmark)

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

    2016-01-01

    of the subdomain IIIf of the internal ribosome entry site (IRES) that directs the initiation of protein synthesis. Rescued viruses were inoculated into pigs. The rescued vPader10 virus, without modifications in the IRES, induced clinical disease in pigs that was very similar to that observed previously...... RNA could be detected. However, the animals inoculated with these mutant viruses seroconverted against CSFV. Thus, these mutant viruses were highly attenuated in vivo. All 4 rescued viruses were also passaged up to 20 times in cell culture. Using full genome sequencing, the same two adaptations within......Classical swine fever virus (CSFV) causes an economically important disease of swine. Four different viruses were rescued from full-length cloned cDNAs derived from the Paderborn strain of CSFV. Three of these viruses had been modified by mutagenesis (with 7 or 8 nt changes) within stem 2...

  5. [The leukocyte count is a valuable parameter for detecting classical swine fever].

    Science.gov (United States)

    Stegeman, J A; Bouma, A; Elbers, A R; Verheijden, J H

    2000-09-01

    In this paper we describe a study of the use of the white blood cell count (wbcc) as a parameter for detecting outbreaks of Classical Swine Fever (CSF). Meta-analysis of the results of challenge experiments revealed that oronasal infection of SPF-pigs with the virulent CSF virus (CSFV) strains Brescia or NL9201 resulted in a significant decrease in the average white blood cell count during the first week after inoculation of the virus. Challenge of conventional finishing pigs and sows with the moderately virulent strain Paderborn also resulted in a significant decrease in the average wbcc. However, this decrease was not observed after inoculation of SPF pigs with the mildly virulent CSFV strains Henken, Zoelen, or Bergen. The usefulness of clinical inspection in combination with wbcc to detect CSF outbreaks in the field was examined using the results of 214 EDTA blood specimens collected from 22 infected herds and 7250 EDTA blood specimens collected from 1450 non-infected herds. Half of the infected herds had been infected with the moderately virulent CSFV strain Venhorst (closely related to strain Paderborn) during the 1997-98 epidemic in the Netherlands. The other half had been infected with the moderately virulent CSFV strain Loraine. Using these data as a starting point, 1000 samples of one to ten specimens were generated by Monte Carlo simulation. These simulated samples and the samples of the non-infected herds were analysed by use of Receiver Operating Characteristic curves. On the basis of that analysis, the optimal number of animals whose wbcc needed to be determined to detect a CSF outbreak was five. With this number of animals, in conjunction with the threshold of 8000 white blood cells per mm3 (meaning that a herd is designated as CSF suspect if one or more of the five specimens has a white blood cell count of 8000 leukocytes/mm3 or less), the test procedure had a herd sensitivity (HSE) of 94.5% and a herd specificity (HSP) of 97.2%). The HSE is defined

  6. 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.

  7. 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.

  8. 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

  9. 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

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

    Directory of Open Access Journals (Sweden)

    Cowled Brendan D

    2012-01-01

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

  11. Co-expression of Erns and E2 genes of classical swine fever virus by replication-defective recombinant adenovirus completely protects pigs against virulent challenge with classical swine fever virus.

    Science.gov (United States)

    Sun, Yongke; Yang, Yuai; Zheng, Huanli; Xi, Dongmei; Lin, Mingxing; Zhang, Xiaomin; Yang, Linfu; Yan, Yulin; Chu, Xiaohui; Bi, Baoliang

    2013-04-01

    The objective of this study was to construct a recombinant adenovirus for future CSFV vaccines used in the pig industry for the reduction of losses involved in CSF outbreaks. The Erns and E2 genes of classical swine fever virus (CSFV), which encode the two main protective glycoproteins from the "Shimen" strain of CSFV, were combined and inserted into the replication-defective human adenovirus type-5 and named the rAd-Erns-E2. Nine pigs were randomly assigned to three treatment groups (three pigs in each group) including the rAd-Erns-E2, hAd-CMV control and DMEM control. Intramuscular vaccination with 2×10(6) TCID(50) of the rAd-Erns-E2 was administered two times with an interval of 21 days. At 42 days post inoculation, pigs in all groups were challenged with a lethal dose of 1×10(3) TCID(50) CSFV "Shimen" strain. Observation of clinical signs was made and the existence of CSFV RNA was detected. Animals in the hAd-CMV and DMEM groups showed severe clinical CSF symptoms and were euthanized from 7 to 10 days after the challenge. However, no adverse clinical CSF signs were observed in vaccinated pigs after the administration of rAd-Erns-E2 and even after CSFV challenge. Neither CSFV RNA nor pathological changes were detected in the tissues of interest of the above vaccinated pigs. These results implied that the recombination adenovirus carrying the Erns-E2 genes could be used to prevent swine from classical swine fever.

  12. 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.

  13. 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...... of CSFV between the hypothetical wild-boar population and the domestic population. Furthermore, the economic impact is assessed taking the perspective of the Danish national budget and the Danish pig industry. We used InterSpreadPlus to model the differential classical swine fever (CSF) risk due to wild...

  14. 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 compromising...

  15. 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. .

  16. 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

  17. Development of a duplex lateral flow assay for simultaneous detection of antibodies against African and Classical swine fever viruses.

    Science.gov (United States)

    Sastre, Patricia; Pérez, Teresa; Costa, Sofia; Yang, Xiaoping; Räber, Alex; Blome, Sandra; Goller, Katja V; Gallardo, Carmina; Tapia, Istar; García, Julia; Sanz, Antonio; Rueda, Paloma

    2016-09-01

    Classical swine fever (CSF) and African swine fever (ASF) are both highly contagious diseases of domestic pigs and wild boar and are clinically indistinguishable. For both diseases, antibody detection is an integral and crucial part of prevention and control measures. The purpose of our study was to develop and initially validate a duplex pen-side test for simultaneous detection and differentiation of specific antibodies against CSF virus (CSFV) and ASF virus (ASFV). The test was based on the major capsid protein VP72 of ASFV and the structural protein E2 of CSFV, both considered the most immunogenic proteins of these viruses. The performance of the pen-side test was evaluated using a panel of porcine samples consisting of experimental, reference, and field sera, with the latter collected from European farms free of both diseases. The new lateral flow assay was able to detect specific antibodies to ASFV or CSFV, showing good levels of sensitivity and specificity. These preliminary data indicate the potential of the newly developed pen-side test for rapid differential detection of antibodies found in the 2 diseases, which is of particular importance in the field and in front-line laboratories where equipment and skilled personnel are limited and control of ASF and CSF is crucial. PMID:27400954

  18. Results of Serological and Molecular Analysis of African and Classical Swine Fever in the Population of Wild Boars in Ukraine

    Directory of Open Access Journals (Sweden)

    Nevolko Oleg Mychailovich

    2015-04-01

    Full Text Available The results of the study of lymphoid organs and sera of wild boars for the presence of DNA of African swine fever (ASF virus and RNA of classical swine fever (CSF virus are presented, as well as the results of a serological examination for the presence of ASF and CSF virus antibodies. The study was conducted in Ukraine between 2008 and 2013. Biological samples were obtained from wild boars shot during the hunting season, and were examined by real-time PCR and ELISA. In total, 5759 sera were tested for CSF virus antibodies and 4856 for ASF virus antibodies by ELISA. Samples of lymphoid organs totalling 1129 were examined by PCR for the detection of CSF virus RNA and 8102 such samples were examined for the detection of ASF virus DNA. CSF virus antibodies were detected in 6.56% of wild boar sera. RNA of CSF virus was also identified in 1 out of 1129 samples tested. ASF virus antibodies or DNA in lymphoid organ samples were not detected.

  19. Within- and between-pen transmission of Classical Swine Fever Virus: a new method to estimate the basic reproduction ratio from transmission experiments

    NARCIS (Netherlands)

    Klinkenberg, D.; Bree, de J.; Laevens, H.; Jong, de M.C.M.

    2002-01-01

    We present a method to estimate basic reproduction ratio R0 from transmission experiments. By using previously published data of experiments with Classical Swine Fever Virus more extensively, we obtained smaller confidence intervals than the martingale method used in the original papers. Moreover, o

  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. 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

  2. When can a veterinarian be expected to detect classical swine fever virus among breeding sows in a herd during an outbreak?

    NARCIS (Netherlands)

    Engel, B.; Bouma, A.; Stegeman, J.A.; Buist, W.; Elbers, A.R.W.; Kogut, J.; Döpfer, D.; Jong, de M.C.M.

    2005-01-01

    The herd sensitivity (HSe) and herd specificity (Hsp) of clinical diagnosis of an infection with classical swine fever (CSF) virus during veterinary inspection of breeding sows in a herd was evaluated. Data gathered from visits to herds during the CSF outbreak in 1997¿1998 in The Netherlands were us

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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.

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

    Science.gov (United States)

    E2, along with E^rns and E1, is an envelope glycoprotein of Classical Swine Fever Virus (CSFV). E2 is involved in several virus functions including cell attachment, host range susceptibility and virulence in natural hosts. In infected cells, E2 forms homodimers as well as heterodimers with E1, media...

  9. 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...

  10. 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...

  11. 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.

  12. 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

    The prophylactic use of vaccines against exotic viral infections in production animals is undertaken exclusively in regions where the disease concerned is endemic. In such areas, the infection pressure is very high and so, to assure optimal protection, the most efficient vaccines are used. However......, in areas considered to be free from these diseases and in which there is the possibility of only limited outbreaks, the use of Differentiation of Infected from Vaccinated Animals (DIVA) or marker vaccines allows for vaccination while still retaining the possibility of serological surveillance...... for the presence of infection. This literature review describes the current knowledge on the use of DIVA diagnostic strategies for three important transboundary animal diseases: foot-and-mouth disease in cloven-hoofed animals, classical swine fever in pigs and avian influenza in poultry....

  13. 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

  14. 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.

  15. 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

  16. 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.

  17. 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

  18. 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

  19. 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.

  20. 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

  1. 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

  2. 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.

  3. 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

  4. 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,...

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

    Science.gov (United States)

    Hadsbjerg, Johanne; Friis, Martin B; Fahnøe, Ulrik; Nielsen, Jens; Belsham, Graham J; Rasmussen, Thomas Bruun

    2016-08-30

    Classical swine fever virus (CSFV) causes an economically important disease of swine. Four different viruses were rescued from full-length cloned cDNAs derived from the Paderborn strain of CSFV. Three of these viruses had been modified by mutagenesis (with 7 or 8 nt changes) within stem 2 of the subdomain IIIf of the internal ribosome entry site (IRES) that directs the initiation of protein synthesis. Rescued viruses were inoculated into pigs. The rescued vPader10 virus, without modifications in the IRES, induced clinical disease in pigs that was very similar to that observed previously with the parental field strain and transmission to in-contact pigs occurred. Two sequence reversions, in the NS2 and NS5B coding regions, became dominant within the virus populations in these infected pigs. Rescued viruses, with mutant IRES elements, did not induce disease and only very limited circulation of viral RNA could be detected. However, the animals inoculated with these mutant viruses seroconverted against CSFV. Thus, these mutant viruses were highly attenuated in vivo. All 4 rescued viruses were also passaged up to 20 times in cell culture. Using full genome sequencing, the same two adaptations within each of four independent virus populations were observed that restored the coding sequence to that of the parental field strain. These adaptations occurred with different kinetics. The combination of reverse genetics and in depth, full genome sequencing provides a powerful approach to analyse virus adaptation and to identify key determinants of viral replication efficiency in cells and within host animals. PMID:27527774

  6. 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

  7. 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.

  8. 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

  9. 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

  10. 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

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

    OpenAIRE

    Dongfang eHu; Lin eLv; Jinyuan eGu; Tongyu eChen; Yihong eXiao; Sidang eLiu

    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...

  12. Progress on technology for detection classical swine fever%猪瘟诊断技术研究进展

    Institute of Scientific and Technical Information of China (English)

    陈江莲

    2012-01-01

    Classical swine fever (CSF) caused by the CSF virus, is an acute, febrile, highly contagious disease in Pigs. Currently, for the complexity of epidemic features, CSF is still a threat to the healthy development of Chinese pig industry. This article summarized the progress on the technology for detection CSF, including etiology methods, serological methods and molecular biological methods, to provide reference for the diagnosis of CSF for farmers.%猪瘟是由猪瘟病毒引起的一种急性、热性、接触性传染病,近年来在我国的流行趋势与发病特点十分复杂,仍是我国养猪业的一大威胁.概述了猪瘟诊断技术的病原学方法、血清学方法和分子生物学方法等的研究进展,为相关养殖人员对猪瘟的诊断提供参考.

  13. 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

  14. 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

  15. 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.

  16. 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.

  17. 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.

  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.

  20. 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.

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

    Directory of Open Access Journals (Sweden)

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

    2015-09-01

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

  2. An approach to model monitoring and surveillance data of wildlife diseases-exemplified by Classical Swine Fever in wild boar.

    Science.gov (United States)

    Stahnke, N; Liebscher, V; Staubach, C; Ziller, M

    2013-11-01

    The analysis of epidemiological field data from monitoring and surveillance systems (MOSSs) in wild animals is of great importance in order to evaluate the performance of such systems. By parameter estimation from MOSS data, conclusions about disease dynamics in the observed population can be drawn. To strengthen the analysis, the implementation of a maximum likelihood estimation is the main aim of our work. The new approach presented here is based on an underlying simple SIR (susceptible-infected-recovered) model for a disease scenario in a wildlife population. The three corresponding classes are assumed to govern the intensities (number of animals in the classes) of non-homogeneous Poisson processes. A sampling rate was defined which describes the process of data collection (for MOSSs). Further, the performance of the diagnostics was implemented in the model by a diagnostic matrix containing misclassification rates. Both descriptions of these MOSS parts were included in the Poisson process approach. For simulation studies, the combined model demonstrates its ability to validly estimate epidemiological parameters, such as the basic reproduction rate R0. These parameters will help the evaluation of existing disease control systems. They will also enable comparison with other simulation models. The model has been tested with data from a Classical Swine Fever (CSF) outbreak in wild boars (Sus scrofa scrofa L.) from a region of Germany (1999-2002). The results show that the hunting strategy as a sole control tool is insufficient to decrease the threshold for susceptible animals to eradicate the disease, since the estimated R0 confirms an ongoing epidemic of CSF.

  3. Evaluation of specific humoral immune response in pigs vaccinated with cell culture adapted classical swine fever vaccine

    Directory of Open Access Journals (Sweden)

    Mrinal K. Nath

    2016-03-01

    Full Text Available Aim: To determine an efficient vaccination schedule on the basis of the humoral immune response of cell culture adapted live classical swine fever virus (CSFV vaccinated pigs and maternally derived antibody (MDA in piglets of vaccinated sows. Materials and Methods: A cell culture adapted live CSFV vaccine was subjected to different vaccination schedule in the present study. Serum samples were collected before vaccination (day 0 and 7, 14, 28, 42, 56, 180, 194, 208, 270, 284 and 298 days after vaccination and were analyzed by liquid phase blocking enzyme-linked immunosorbent assay. Moreover, MDA titre was detected in the serum of piglets at 21 and 42 days of age after farrowing of the vaccinated sows. Results: On 28 days after vaccination, serum samples of 83.33% vaccinated pigs showed the desirable level of antibody titer (log10 1.50 at 1:32 dilution, whereas 100% animals showed log10 1.50 at 1:32 dilution after 42 days of vaccination. Animals received a booster dose at 28 and 180 days post vaccination showed stable high-level antibody titre till the end of the study period. Further, piglets born from pigs vaccinated 1 month after conception showed the desirable level of MDA up to 42 days of age. Conclusion: CSF causes major losses in pig industry. Lapinised vaccines against CSFV are used routinely in endemic countries. In the present study, a cell culture adapted live attenuated vaccine has been evaluated. Based on the level of humoral immune response of vaccinated pigs and MDA titer in piglets born from immunized sows, it may be concluded that the more effective vaccination schedule for prevention of CSF is primary vaccination at 2 months of age followed by booster vaccination at 28 and 180 days post primary vaccination and at 1 month of gestation.

  4. Factors affecting the infectivity of tissues from pigs with classical swine fever: thermal inactivation rates and oral infectious dose.

    Science.gov (United States)

    Cowan, Lucie; Haines, Felicity J; Everett, Helen E; Crudgington, Bentley; Johns, Helen L; Clifford, Derek; Drew, Trevor W; Crooke, Helen R

    2015-03-23

    Outbreaks of classical swine fever are often associated with ingestion of pig meat or products derived from infected pigs. Assessment of the disease risks associated with material of porcine origin requires knowledge on the likely amount of virus in the original material, how long the virus may remain viable within the resulting product and how much of that product would need to be ingested to result in infection. Using material from pigs infected with CSFV, we determined the viable virus concentrations in tissues that comprise the majority of pork products. Decimal reduction values (D values), the time required to reduce the viable virus load by 90% (or 1 log10), were determined at temperatures of relevance for chilling, cooking, composting and ambient storage. The rate of CSFV inactivation varied in different tissues. At lower temperatures, virus remained viable for substantially longer in muscle and serum compared to lymphoid and fat tissues. To enable estimation of the temperature dependence of inactivation, the temperature change required to change the D values by 90% (Z values) were determined as 13 °C, 14 °C, 12 °C and 10 °C for lymph node, fat, muscle and serum, respectively. The amount of virus required to infect 50% of pigs by ingestion was determined by feeding groups of animals with moderately and highly virulent CSFV. Interestingly, the virulent virus did not initiate infection at a lower dose than the moderately virulent strain. Although higher than for intranasal inoculation, the amount of virus required for infection via ingestion is present in only a few grams of tissue from infected animals.

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

    Science.gov (United States)

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

    2013-10-25

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

  6. 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.

  7. 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

  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. 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.

  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. 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.

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

    Science.gov (United States)

    Zhou, Niu; Xing, Gang; Zhou, Jianwei; Jin, Yulan; Liang, Cuiqin; Gu, Jinyan; Hu, Boli; Liao, Min; Wang, Qin; Zhou, Jiyong

    2015-01-01

    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. PMID:26431319

  13. 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

  14. 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.

  15. 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.

  16. Enhanced immunity against classical swine fever in pigs induced by prime-boost immunization using an alphavirus replicon-vectored DNA vaccine and a recombinant adenovirus.

    Science.gov (United States)

    Sun, Yuan; Li, Na; Li, Hong-Yu; Li, Miao; Qiu, Hua-Ji

    2010-09-15

    Classical swine fever (CSF) - caused by the classical swine fever virus (CSFV) - is a fatal disease of pigs that is responsible for extensive losses to the swine industry worldwide. We had demonstrated previously that a prime-boost vaccination strategy using an alphavirus (Semliki Forest virus, SFV) replicon-vectored DNA vaccine (pSFV1CS-E2) and a recombinant adenovirus (rAdV-E2) expressing the E2 glycoprotein of CSFV induced enhanced immune responses in a mouse model. In this study, we evaluated further the efficacy of the heterologous prime-boost immunization approach in pigs, the natural host of CSFV. The results showed that the pigs (n=5) receiving pSFV1CS-E2/rAdV-E2 heterologous prime-boost immunization developed significantly higher titers of CSFV-specific neutralizing antibodies and comparable CD4(+) and CD8(+) T-cell proliferation, compared to the pigs receiving double immunizations with rAdV-E2 alone. When challenged with virulent CSFV Shimen strain, the pigs of the heterologous prime-boost group did not show clinical symptoms or viremia, which were observed in one of the 5 pigs immunized with rAdV-E2 alone and all the 5 control pigs immunized with an empty adenovirus. The results demonstrate that the heterologous DNA prime and recombinant adenovirus boost strategy can induce solid protective immunity.

  17. 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

  18. 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

  19. Advance in New Kind of Vaccine for Classical Swine Fever%新型猪瘟疫苗研究进展

    Institute of Scientific and Technical Information of China (English)

    谢沄; 白华

    2008-01-01

    猪瘟(Classical swine fever, CSF)是一种严重威胁养猪业的传染病,预防猪瘟最主要的方法为注射弱毒疫苗,由于传统弱毒疫苗存在着一些不足,需要研制高效而更具特异性的新型猪瘟疫苗.该文简要介绍了新型猪瘟疫苗的研究现状,并对其应用前景进行了分析.

  20. How to survey classical swine fever in wild boar (Sus scrofa) after the completion of oral vaccination? Chasing away the ghost of infection at different spatial scales

    OpenAIRE

    2016-01-01

    Oral mass vaccination (OMV) is considered as an efficient strategy for controlling classical swine fever (CSF) in wild boar. After the completion of vaccination, the presence of antibodies in 6–12 month-old hunted wild boars was expected to reflect a recent CSF circulation. Nevertheless, antibodies could also correspond to the long-lasting of maternal antibodies. This paper relates an experience of surveillance which lasted 4 years after the completion of OMV in a formerly vaccinated area, in...

  1. 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...

  2. 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

  3. Simulation of Cross-border Impacts Resulting from Classical Swine Fever Epidemics within the Netherlands and Germany.

    Science.gov (United States)

    Hop, G E; Mourits, M C M; Oude Lansink, A G J M; Saatkamp, H W

    2016-02-01

    The cross-border region of the Netherlands (NL) and the two German states of North Rhine Westphalia (NRW) and Lower Saxony (LS) is a large and highly integrated livestock production area. This region increasingly develops towards a single epidemiological area in which disease introduction is a shared veterinary and, consequently, economic risk. The objectives of this study were to examine classical swine fever (CSF) control strategies' veterinary and direct economic impacts for NL, NRW and LS given the current production structure and to analyse CSF's cross-border causes and impacts within the NL-NRW-LS region. The course of the epidemic was simulated by the use of InterSpread Plus, whereas economic analysis was restricted to calculating disease control costs and costs directly resulting from the control measures applied. Three veterinary control strategies were considered: a strategy based on the minimum EU requirements, a vaccination and a depopulation strategy based on NL and GER's contingency plans. Regardless of the veterinary control strategy, simulated outbreak sizes and durations for 2010 were much smaller than those simulated previously, using data from over 10 years ago. For example, worst-case outbreaks (50th percentile) in NL resulted in 30-40 infected farms and lasted for two to four and a half months; associated direct costs and direct consequential costs ranged from €24.7 to 28.6 million and €11.7 to 26.7 million, respectively. Both vaccination and depopulation strategies were efficient in controlling outbreaks, especially large outbreaks, whereas the EU minimum strategy was especially deficient in controlling worst-case outbreaks. Both vaccination and depopulation strategies resulted in low direct costs and direct consequential costs. The probability of cross-border disease spread was relatively low, and cross-border spread resulted in small, short outbreaks in neighbouring countries. Few opportunities for further cross-border harmonization and

  4. 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.

  5. 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.

  6. 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

  7. 我国猪瘟流行新特点与疫苗免疫研究%New Epidemic Characteristics of Classical Swine Fever in China and the Research of Vaccine and Immunization

    Institute of Scientific and Technical Information of China (English)

    宁宜宝; 吴文福

    2011-01-01

    The author describes the new epidemic characteristics of classical swine fever, points out six reasons which cause immune failure, and introduces the history and study progress of classical swine fever vaccine. Two key points for the control of classical swine fever have been put forward.%对我国的猪瘟流行的新特点进行了描述,详细分析了造成猪瘟疫苗免疫失败的6大原因,并且对疫苗的发展历史和研究进展进行了详细介绍,提出了猪瘟防控的两个关键环节为种猪群野毒感染的控制及有效的免疫接种。

  8. 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 .

  9. 猪瘟控制(净化)对母猪分娩率的影响%Influence of Controlling (Eradicating) Classic Swine Fever to Sow Parturition Rate in a Large Scale Pig Farm

    Institute of Scientific and Technical Information of China (English)

    罗才庆

    2014-01-01

    Objective:Investigate and analyze whether the sow parturition rate could be improved by controlling (eradicating) classic swine fever in a large scale pig farm. Method:The antibodies of classic swine fever of sow were detected with Enzyme-linked immunosorbent assay (ELISA) on a large scale pig farm in Longyan city. The sows which the antibodies of classic swine fever were below standard were sifted out controlling (eradicating) classic swine fever. The data of the sow parturition rate were analyzed before controlling (eradicating) classic swine fever and after. Results:The numbers of the sows which showed returning to estrus, abortion and non-pregnancy have reduced and the sow parturition rate was improved obviously by controlling (eradicating) classic swine fever. Con-clusion:Controlling (eradicating) classic swine fever can improve the sow parturition efficiency. It is of a great sig-nificance for a large scale pig farm to control (eradicate) classic swine fever.%目的:通过对某猪场母猪实施猪瘟控制(净化)方案,研究分析能否提高该猪场的母猪分娩率。方法:采用酶联免疫吸附试验(ELISA)对龙岩市某规模化猪场的母猪进行猪瘟抗体检测,对猪瘟抗体检测不合格(阻断率小于40%)且同时满足两条及以上淘汰标准的种猪实行淘汰以达到猪瘟控制(净化)目的,并对猪瘟控制(净化)前后配种分娩结果进行收集、统计。结果:猪瘟控制(净化)后,母猪返情、流产、空胎数量减少,分娩率明显提升。结论:猪瘟控制(净化)可以提高母猪分娩率,实行猪瘟控制(净化)对规模化猪场具有重大意义。

  10. 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

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

    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

    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.%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。

  12. 猪瘟病毒E2蛋白研究进展%Application progress in E2 protein of Classical Swine Fever Virus

    Institute of Scientific and Technical Information of China (English)

    江馗语

    2013-01-01

    Classical swine fever(CSF)is a highly contagious, acute, hyperthermic, multi-systemic hemorrhagic viral disease of pigs, which caused by classical swine fe-ver virus(CSFV), a member of the genus Pestivirus of the Flaviviridae. CSF is preva-lent in all continents except North America and Oceania,it is distributed worldwide, and it has relapsed in some European countries(Netherlands, Belgium, Britain, Germa-ny, Italy, Spain, etc.)which had eliminated CSF. Although we have used HCLV vaccine for inoculation for a long time,but CSF still exists in our country and happens from frequency of pandemic into erratic regional dissemination. Latent and persistent in-fection has increased. Therefore, we need clear swine fever virus genome structure and the most research value immunological antigen protein structures to provide a theoretical basis for the development of new and effective vaccines and diagnostic reagents. In this paper,we have reviewed the research progress in genomic structure of CSFV,structure, function, epitopes,expression and applications of E2 protein.%猪瘟(Classical Swine Fever,CSF)是由猪瘟病毒(Classical Swine Fever Virus,CSFV)引起的一种急性、接触性传染病。目前该病流行于除北美洲和大洋洲以外的其他大洲和地区,呈世界性分布,在一些原已宣布消灭猪瘟的欧洲国家(荷兰、比利时、英国、德国、意大利、西班牙等)又相继复发。虽然我国长期坚持全面接种猪瘟兔化弱毒疫苗,但目前猪瘟在我国依然存在,流行特点从以往的频发大面积流行转变为无规律区域性的散发,隐性持续性感染病例增多,因此应明确猪瘟病毒的基因组结构和最具免疫防制研究价值的抗原蛋白结构,为研制新型有效的疫苗和诊断试剂提供理论依据。本文就猪瘟病毒的基因组结构、猪瘟病毒E2蛋白的结构、功能、所包含的抗原表位以及E2蛋白的表达应用等方面的研究进展作以综述。

  13. 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.

  14. 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.

  15. 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

  16. The Epidemic and Control of Classical Swine Fever%猪瘟的流行与控制

    Institute of Scientific and Technical Information of China (English)

    刘菲; 李成军; 黄勇

    2005-01-01

    猪瘟(Classical Swine Fever,CSF or Hog Cholera,HC)是由猪瘟病毒引起的猪的一种高度接触性传染病,被OIE列入A类传染病。早在20世纪50年代,我国便成功的培育出1株免疫原性好又安全的猪瘟兔化弱毒“C”株,它是目前国际上应用最广泛、我国惟一采用的猪瘟疫苗毒株,它的使用有效地控制了猪瘟在我国的急性发生和大流行,

  17. Current situation of the studies of the new type vaccine against classical swine fever%新型猪瘟疫苗研究现状

    Institute of Scientific and Technical Information of China (English)

    贾洪林; 仇华吉; 李娜; 张守发; 童光志

    2005-01-01

    猪瘟(classical swine fever,CSF)是由猪瘟病毒(classical swine fever virus,CSFV)引起的一种以急性出血和发热为主要特征的烈性传染病,死亡率极高,对养猪业危害极大,已被国际兽疫局(OIE)列为A类动物传染病。许多国家已经针对该病施行了控制和根除措施,但因为生猪及其产品贸易的全球化、养猪业的集约化和野猪群中CSFV的持久性等原因,CSF仍然对世界养猪业构成很大威胁。特别是20世纪70年代后期,猪瘟的流行形式发生了很大变化,猪瘟地区散发性流行和非典型猪瘟的发生等。促使人们不断探索研制新型疫苗的新策略。

  18. 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。

  19. 河源某猪场两种猪瘟疫苗田间免疫效果对比试验%Immune result of two kinds of classical swine fever vaccines in one pig

    Institute of Scientific and Technical Information of China (English)

    姚文凤; 陈明凯

    2011-01-01

    通过在河源某猪场,对不同厂家两种猪瘟疫苗单独使用及混合使用后的的免疫效果对比,得出以下结论:首免和二免均使用猪瘟传代细胞苗免疫的效果最好;首免使用猪瘟脾淋苗,二免使用猪瘟传代细胞苗免疫的效果次之;首免和二免均使用脾淋苗免疫的效果最差。%The experiments comparing the immunity effect of two kinds of classical swine fever vaccines manufactured by different companies were done in one pig farm of Heyuan. The experiments showed that the result in pigs using classical swine fever cell vaccine in the first and second immunization was the best, the result in pigs using classical swine fever spleen vaccine in the first immunization and cell vaccine in the second immunization was better and the result in pigs using classical swine fever spleen vaccine in the first and second immunization was the worst.

  20. 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...

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

    Science.gov (United States)

    Widén, F; Everett, H; Blome, S; Fernandez Pinero, J; Uttenthal, A; Cortey, M; von Rosen, T; Tignon, M; Liu, L

    2014-10-01

    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 animals, the so called DIVA principle. This inability complicates monitoring of disease and stops international trade thereby limiting use of the vaccine in many regions. The C-strain vaccine is safe to use and gives good protection. It is licensed for emergency vaccination in the EU in event of an outbreak. Two genetic assays that can distinguish between wild type virus and C-strain vaccines have recently been developed. Here the results from a comparison of these two real-time RT-PCR assays in an interlaboratory exercise are presented. Both assays showed similar performance.

  2. 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

  3. Impact of porcine reproductive and respiratory syndrome virus and porcine circovirus-2 infection on the potency of the classical swine fever vaccine (LOM strain).

    Science.gov (United States)

    Lim, Seong-In; Jeoung, Hye-Young; Kim, Byounghan; Song, Jae-Young; Kim, Jaejo; Kim, Ha-Young; Cho, In-Soo; Woo, Gye-Hyeong; Lee, Joong-Bok; An, Dong-Jun

    2016-09-25

    The classical swine fever (CSF) vaccine, which is derived from the LOM strain of the CSF virus (CSFV), induces protective immunity against CSFV infection. However, several factors influence vaccine efficacy. Evidence suggests that infection by porcine reproductive and respiratory syndrome virus (PRRSV) and/or porcine circovirus 2 (PCV2) reduces the efficacy of several vaccines. Here, we examined the effect of PRRSV or PCV2 alone or co-infection by PRRSV/PCV2 on the potency of the LOM vaccine in pigs. Neither CSFV antibody levels nor the period during which CSFV antigens were detectable in LOM-vaccinated pigs were negatively affected by infection by PRRSV or PCV2. However, co-infection with PRRSV/PCV2 may affect the replication or activity of the CSF vaccine virus in pigs vaccinated with the LOM strain, although CSFV antibody levels were not negatively affected. Nevertheless, the LOM vaccine afforded complete protection against a virulent strain of CSFV. PMID:27599928

  4. 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.

  5. 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.

  6. The comparison of ARMA, exponential smoothing and seasonal index model for predicting incidence of classical swine fever%3种模型预测猪瘟发病率的比较

    Institute of Scientific and Technical Information of China (English)

    许丹宁; 肖建华; 王洪斌

    2009-01-01

    How to control or eradicate classical swine fever has always been a challenge. The early estimation to incidence of classical swine fever is the key research direction at present. In this study, ARMA,exponential smoothing and seasonal index model is adopted for predicting incidence of classical swine fever, and evaluating the precision of these three models using MSE,MAE,MPE and MAPE. The results showed that the four kinds of evaluation indexes of ARMA model are minimum, the predictive value of ARMA model is close to the real values, and ARMA model has the fittest predicting effect. The method of quantitative predictions is used in numerically simulating the incidence of classical swine fever that can reflect the transmission tendency and incidence's change of classical swine fever in recent years and provide theoretical basis for making optimum preventive strategies.%如何控制和消灭猪瘟一直是防控工作的难点,对猪瘟发病率进行早期预测是目前研究的重点方向.本研究拟用ARMA模型、指数平滑模型和季节指数模型对猪瘟发病率进行预测,采用MSE、MAE、MPE和MAPE来评价模型的精确度.结果显示,ARMA模型的4种评价指标均为最小值,预测值最接近真实值,对猪瘟发病率的预测效果较好.应用定量预测法对猪瘟发病率进行数值上的模拟,可较好的反映近几年猪瘟的流行趋势和发病率的变化,为制定最优防控策略提供理论依据.

  7. 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.

  8. Progress in new-type vaccines against classical swine fever%新型猪瘟疫苗研究进展

    Institute of Scientific and Technical Information of China (English)

    王春花; 孙元; 仇华吉

    2013-01-01

    Classical swine fever (CSF),an acute and highly contagious disease of swine,is caused by classical swine fever virus.CSF is one of the most devastating diseases to the pig industry worldwide and results in serious economic losses.Currently prophylactic vaccination is still an important strategy for the control of CSF.Live attenuated vaccines (such as C-strain) are safe and effective.However,there are significant changes in the clinical features of CSF,displaying concurrent typical and atypical CSF,and simultaneous inapparent and persistent infections.Immunization failure has been reported frequently and it is difficult to distinguish between wild-type infected and vaccinated animals (DIVA).So there is an urgent need to develop more effective and safer DIVA or marker vaccines for the control of CSF.In this review,some of the most recent advances in new-type vaccines against CSF,including DNA vaccines,live virus-vectored vaccines,protein or peptide-based vaccines,gene-deleted vaccines and chimeric pestivirus-based vaccines,are reviewed and discussed.%猪瘟是由猪瘟病毒引起猪的一种急性、热性和高度接触性传染病.该病呈世界性分布,给世界养猪业造成了巨大的经济损失.目前,疫苗接种仍然是防控猪瘟的主要手段.虽然传统的猪瘟弱毒疫苗(如C株)安全有效,但猪瘟的临床表现发生了很大变化,呈现典型猪瘟和非典型猪瘟共存、隐性感染和持续感染并现,免疫失败的现象时有报道,且不能区分野毒感染和免疫接种.因此,研制安全、高效、能区分野毒感染和疫苗免疫动物(DIVA)的新型猪瘟疫苗极为必要.文中就近年来开发的核酸疫苗、病毒活载体疫苗、基于蛋白/肽的疫苗、基因缺失疫苗、嵌合瘟病毒疫苗等新型DIVA猪瘟疫苗作一综述.

  9. 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.

  10. 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

  11. 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...... and specificity values. Nevertheless, some in-house systems had unspecific reactions or suboptimal sensitivity with only a single CSFV genotype. Follow-up actions involved either improvement of suboptimal assays or replacement of specific laboratory assays with the FLI protocol, with or without modifications....... In conclusion, the ring trial showed reliability of classical swine fever diagnosis on an international level and helped to optimize CSFV-specific RT-PCR diagnostics....

  12. 猪瘟免疫抗体水平监测及免疫效果评估分析%Detection of antibody level and evaluation of immune effect in Classical Swine Fever

    Institute of Scientific and Technical Information of China (English)

    付少刚; 马建春; 曹晓真; 王晓龙

    2011-01-01

    The variation of antibody eligible rate was discovered by monitoring the antibody level of Classical Swine Fever in Yinchuan from 2005 to 2010.In order to explore the development and prevalent regulations of Classical swine Fever,and provide reference for its control and prevention,the relative factors were analyzed.%通过2005-2010年对银川市猪瘟抗体水平的监测,明确猪瘟抗体合格率变化特点,分析相关原因,探寻猪瘟的发生动态和流行规律,为指导和制定猪瘟防控措施提供参考。

  13. 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.

  14. Prevention and control of Foot-and-Mouth disease, classical swine fever and Avian influenza in the European Union: An integrated analysis of epidemiological, economic and social-ethical aspects

    OpenAIRE

    Asseldonk, van, N.; Jong, de, D.; Vlieger, de, J.J.; Huirne, R.B.M.

    2005-01-01

    The recent outbreaks of Foot-and-Mouth Disease (FMD), Classical Swine Fever (CSF), and highly pathogenetic Avian Influenza (AI) in the European Union (EU) have shown that such contagious animal diseases can have a devastating impact in terms of animal welfare, economics and societal outcry and disturbance. Insights into the three interrelated, aspects of epidemiology, economics, and social-ethics are crucial in order to better prevent and control contagious diseases in the future. Because of ...

  15. 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...

  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. 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.

  18. 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.

  19. 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

  20. 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.

  1. Evaluation of the spatial patterns and risk factors, including backyard pigs, for classical swine fever occurrence in Bulgaria using a Bayesian model

    Directory of Open Access Journals (Sweden)

    Beatriz Martínez-López

    2014-05-01

    Full Text Available 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 it is one of the countries for which both backyard pig and farm counts were available. Results reveal that the high-risk areas are typically concentrated in areas with small family farms, high numbers of outgoing pig shipments and low levels of personal consumption (i.e. economically deprived areas. Identification of risk factors and high-risk areas for CSF will allow to targeting risk-based surveillance strategies leading to prevention, control and, ultimately, elimination of the disease in Bulgaria and other countries with similar socio-epidemiological conditions.

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

    Science.gov (United States)

    von Rosen, T; Lohse, L; Nielsen, J; Uttenthal, Å

    2013-12-01

    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 6-month-old Danish pigs, the strains used for inoculation were classified as being of low (Bergen), low to moderate (Eystrup) and moderate to high (Lithuania) virulence. The cytokines interferon-alpha (INF-α), interleukin-8 (IL-8) and tumor necrosis factor-alpha (TNF-α) showed increased levels after CSFV infection with more or less comparable course in the 3 groups. However, the cytokine level peaked with a 2-3 days delay in pigs infected with the low virulent strain compared to those infected with a moderately or highly virulent strain. These findings may indicate that INF-α, IL-8 and TNF-α are involved in the immune response during CSFV infection with strains of different virulence.

  3. Effects of the nuclear localization of the N(pro) protein of classical swine fever virus on its virulence in pigs.

    Science.gov (United States)

    Li, Yongfeng; Shen, Liang; Sun, Yuan; Wang, Xiao; Li, Chao; Huang, Junhua; Chen, Jianing; Li, Lianfeng; Zhao, Bibo; Luo, Yuzi; Li, Su; Qiu, Hua-Ji

    2014-12-01

    The N(pro) protein of classical swine fever virus (CSFV) is localized in the cytoplasm and nucleus. However, it is unknown whether the nuclear localization of N(pro) correlates with the virulence of CSFV in the host. Previously, we showed that the N(pro) protein fused with interferon regulatory factor 3 (IRF3) was present only in the cytoplasm. Here, we generated and evaluated a recombinant CSFV vSM-IRF3 harboring the IRF3 gene inserted into the N(pro) gene of the highly virulent CSFV Shimen strain. Compared to the even nuclear and cytoplasmic distribution of the enhanced green fluorescent protein (EGFP)-N(pro) fusion expressed by the recombinant CSFV EGFP-CSFV, vSM-IRF3 expressed an IRF3-N(pro) fusion protein that only was localized in the cytoplasm. vSM-IRF3 was markedly attenuated in vitro and in vivo, and the inoculated pigs were completely protected from lethal CSFV challenge, whereas the parental virus as well as EGFP-CSFV exhibited a typical virulent phenotype. Taken together, the nuclear localization of N(pro) plays a significant role in the CSFV replication and virulence.

  4. Induction of immune responses in mice and pigs by oral administration of classical swine fever virus E2 protein expressed in rice calli.

    Science.gov (United States)

    Jung, Myunghwan; Shin, Yun Ji; Kim, Ju; Cha, Seung-Bin; Lee, Won-Jung; Shin, Min-Kyoung; Shin, Seung Won; Yang, Moon-Sik; Jang, Yong-Suk; Kwon, Tae-Ho; Yoo, Han Sang

    2014-12-01

    Classical swine fever (CSF), caused by the CSF virus (CSFV), is a highly contagious disease in pigs. In Korea, vaccination using a live-attenuated strain (LOM strain) has been used to control the disease. However, parenteral vaccination using a live-attenuated strain still faces a number of problems related to storage, cost, injection stress, and differentiation of CSFV infected and vaccinated pigs. Therefore, two kinds of new candidates for oral vaccination have been developed based on the translation of the E2 gene of the SW03 strain, which was isolated from an outbreak of CSF in 2002 in Korea, in transgenic rice calli (TRCs) from Oriza sativa L. cv. Dongjin to express a recombinant E2 protein (rE2-TRCs). The expression of the recombinant E2 protein (rE2) in rE2-TRCs was confirmed using Northern blot, SDS-PAGE, and Western blot analysis. Immune responses to the rE2-TRC in mice and pigs were investigated after oral administration. The administration of rE2-TRCs increased E2-specific antibodies titers and antibody-secreting cells when compared to animals receiving the vector alone (p Pigs receiving rE2-TRCs also showed an increase in IL-8, CCL2, and the CD8+ subpopulation in response to stimulation with prE2. These results suggest that oral administration of rE2-TRCs can induce E2-specific immune responses.

  5. 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.

  6. 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

  7. 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.

  8. Research progress in the technology of prevention and control for classical swine fever (CSF)%猪瘟防控技术的研究进展

    Institute of Scientific and Technical Information of China (English)

    栾培贤; 肖建华; 王洪斌

    2016-01-01

    猪瘟(classical swine fever,CSF)是高度传染性动物疫病,给全世界养猪业造成巨大的经济损失.清除和控制猪瘟的发生,需从多个方面提高猪瘟防控水平,才能达到猪瘟综合防控的目的.近年来,猪瘟防控相关方面的研究主要集中在以下几个点:开发有效的新型猪瘟疫苗、构建快速高效的猪瘟诊断方法、应用计算机模拟技术研究猪瘟防控策略及建立可靠的猪瘟疫情监测体系.文章详细介绍了国内外有关猪瘟防控方面的研究进展.

  9. [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

  10. 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.

  11. 猪瘟防制研究的现状及发展趋势%Advances on prevention research of classical swine fever

    Institute of Scientific and Technical Information of China (English)

    吕宗吉; 涂长春; 余兴龙

    2001-01-01

    @@ 由于猪瘟(Classical swine fever,简称CSF)对养猪业的毁灭性打击,各养猪国家特别是CSF存在国都高度重视对CSF及其防制的研究.为此,各国都投入了大量的人力、物力与财力,做了大量的工作,并取得了很大的成绩.尽管消灭CSF花费巨大,但所带来的收益明显大于防疫的支出.那些无猪瘟的国家对CSF的研究也丝毫不敢松懈,除了禁止从CSF存在国进口活猪、猪肉及猪肉制品,强化口岸检疫,密切监测有CSF国家的疫情,建立健全CSF疫情报告、监测、法律法规和扑灭措施等之外,也还继续开展对CSF的研究工作.

  12. 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.

  13. 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

  14. T-cell factor-4 and MHC upregulation in pigs receiving a live attenuated classical swine fever virus (CSFV) vaccine strain with interferon-gamma adjuvant.

    Science.gov (United States)

    Fan, Y-H; Lin, Y-L; Hwang, Y-C; Yang, H-C; Chiu, H-C; Chiou, S-H; Jong, M-H; Chow, K-C; Lin, C-C

    2016-10-01

    The effect of co-administration of interferon (IFN)-γ in pigs undergoing vaccination with an attenuated strain (LPC) of classical swine fever virus (CSFV) was investigated. Unvaccinated pigs demonstrated pyrexia and died 7-9 days after challenge with virulent CSFV. Pigs receiving the attenuated vaccine remained healthy after virus challenge, except for mild, transient pyrexia, whereas pigs receiving IFN-γ simultaneously with the vaccine demonstrated normal body temperatures after virus challenge. Examination by nested RT-PCR revealed greater viral load in the spleens of the pigs vaccinated with the attenuated CSFV, compared with those that had additionally received IFN-γ. Expression of major histocompatibility complex (MHC) class I and MHC class II molecules was upregulated in the spleens of the IFN-γ treated vaccinated pigs, demonstrated by immunohistochemistry. Based on Western blot analysis, anti-CSFV IgG2 antibodies were elevated in vaccinated pigs by co-administration of IFN-γ (IFN-γ(Hi): P < 0.01; IFN-γ(Lo): P <0.05). By employing the suppression subtractive hybridization technique, RT-PCR, in situ hybridization, and immunohistochemistry, T-cell factor-4 (Tcf-4) mRNA and protein expression were found to be upregulated in the spleens of vaccinated pigs that had received IFN-γ. This study suggests involvement of Tcf-4 in IFN-γ-mediated immune regulation following CSFV vaccination. PMID:27687943

  15. 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

  16. 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.

  17. 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

  18. 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

  19. 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.

  20. 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)

  1. 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

  2. How to survey classical swine fever in wild boar (Sus scrofa) after the completion of oral vaccination? Chasing away the ghost of infection at different spatial scales.

    Science.gov (United States)

    Saubusse, Thibault; Masson, Jean-Daniel; Le Dimma, Mireille; Abrial, David; Marcé, Clara; Martin-Schaller, Regine; Dupire, Anne; Le Potier, Marie-Frédérique; Rossi, Sophie

    2016-01-25

    Oral mass vaccination (OMV) is considered as an efficient strategy for controlling classical swine fever (CSF) in wild boar. After the completion of vaccination, the presence of antibodies in 6-12 month-old hunted wild boars was expected to reflect a recent CSF circulation. Nevertheless, antibodies could also correspond to the long-lasting of maternal antibodies. This paper relates an experience of surveillance which lasted 4 years after the completion of OMV in a formerly vaccinated area, in north-eastern France (2010-2014). First, we conducted a retrospective analysis of the serological data collected in 6-12 month-old hunted wild boars from 2010 up to 2013, using a spatial Bayesian model accounting for hunting data autocorrelation and heterogeneity. At the level of the whole area, seroprevalence in juvenile boars decreased from 28% in 2010-2011 down to 1% in 2012-2013, but remained locally high (above 5%). The model revealed the existence of one particular seroprevalence hot-spot where a longitudinal survey of marked animals was conducted in 2013-2014, for deciphering the origin of antibodies. Eleven out of 107 captured piglets were seropositive when 3-4 months-old, but their antibody titres progressively decreased until 6-7 months of age. These results suggest piglets were carrying maternal antibodies, few of them carrying maternal antibodies lasting until the hunting season. Our study shows that OMV may generate confusion in the CSF surveillance several years after the completion of vaccination. We recommend using quantitative serological tools, hunting data modelling and capture approaches for better interpreting serological results after vaccination completion. Surveillance perspectives are further discussed.

  3. Npro of classical swine fever virus contributes to pathogenicity in pigs by preventing type I interferon induction at local replication sites.

    Science.gov (United States)

    Tamura, Tomokazu; Nagashima, Naofumi; Ruggli, Nicolas; Summerfield, Artur; Kida, Hiroshi; Sakoda, Yoshihiro

    2014-04-17

    Classical swine fever (CSF) caused by CSF virus (CSFV) is a highly contagious disease of pigs. The viral protein Npro of CSFV interferes with alpha- and beta-interferon (IFN-α/β) induction by promoting the degradation of interferon regulatory factor 3 (IRF3). During the establishment of the live attenuated CSF vaccine strain GPE-, Npro acquired a mutation that abolished its capacity to bind and degrade IRF3, rendering it unable to prevent IFN-α/β induction. In a previous study, we showed that the GPE- vaccine virus became pathogenic after forced serial passages in pigs, which was attributed to the amino acid substitutions T830A in the viral proteins E2 and V2475A and A2563V in NS4B. Interestingly, during the re-adaptation of the GPE- vaccine virus in pigs, the IRF3-degrading function of Npro was not recovered. Therefore, we examined whether restoring the ability of Npro to block IFN-α/β induction of both the avirulent and moderately virulent GPE--derived virus would enhance pathogenicity in pigs. Viruses carrying the N136D substitution in Npro regained the ability to degrade IRF3 and suppress IFN-α/β induction in vitro. In pigs, functional Npro significantly reduced the local IFN-α mRNA expression in lymphoid organs while it increased quantities of IFN-α/β in the circulation, and enhanced pathogenicity of the moderately virulent virus. In conclusion, the present study demonstrates that functional Npro influences the innate immune response at local sites of virus replication in pigs and contributes to pathogenicity of CSFV in synergy with viral replication.

  4. Classical swine fever in 6- and 11-week-old pigs: haematological and immunological parameters are modulated in pigs with mild clinical disease.

    Science.gov (United States)

    Nielsen, Jens; Lohse, Louise; Rasmussen, Thomas Bruun; Uttenthal, Ase

    2010-12-01

    The severity of classical swine fever virus (CSFV) infection is believed to be determined by different factors, including the virulence of the strain as well as factors related to the host. In the present study, we infected 6- and 11-week-old pigs of unique sanitary status with CSFV strain Eystrup to elucidate the influence of age on virulence. In both age-groups, a mild clinical course correlated well with the gross-pathological findings at necropsy. The minor variations of clinical, pathological, haematological and immunological parameters between the various age-groups demonstrated that a time-span of approximately 1 month of age did not play a significant role for the severity of CSF disease in young, weaned pigs. The detailed analysis of various haematological and cellular immunological parameters proved to provide a valuable set of objective reference values for healthy control pigs and for pigs with mild clinical CSF disease. Despite that only mild disease occurred in the infected pigs, modulations of haematological and immunological parameters were observed. Depletion of B cell and a number of T cell populations in peripheral blood was observed in both age-groups, however, the changes being most pronounced in the 6-week-old pigs. In the infected pigs, but not in any of the controls, a population of large granulocytes (LG) developed in peripheral blood. The LG, which were demonstrated to be identical to low-density granulocytes, appeared before the development of viraemia. Therefore, we suggest detection of LDG to be used as an additional tool in early CSF diagnosis. The observation that pigs with a unique, high sanitary status only developed mild disease after infection with CSFV strain Eystrup emphasizes the important role of the host in the CSFV virulence puzzle.

  5. Porcine complement regulatory protein CD46 and heparan sulfates are the major factors for classical swine fever virus attachment in vitro.

    Science.gov (United States)

    Dräger, Carolin; Beer, Martin; Blome, Sandra

    2015-03-01

    Classical swine fever virus (CSFV) is the causative agent of a severe multi-systemic disease of pigs. While several aspects of virus-host-interaction are known, the early steps of infection remain unclear. For the closely related bovine viral diarrhea virus (BVDV), a cellular receptor is known: bovine complement regulatory protein CD46. Given that these two pestiviruses are closely related, porcine CD46 is also a candidate receptor for CSFV. In addition to CD46, cell-culture-adapted CSFV strains have been shown to use heparan sulfates as an additional cellular factor. In the present study, the interaction of field-type and cell-culture-adapted CSFV with a permanent porcine cell line or primary macrophages was assessed using anti-porcine CD46 monoclonal antibodies and a heparan-sulfate-blocking compound, DSTP-27. The influence of receptor blocking was assessed using virus titration and quantitative PCR. Treatment of cells with monoclonal antibodies against porcine CD46 led to a reduction of viral growth in both cell types. The effect was most pronounced with field-type CSFV. The blocking could be enhanced by addition of DSTP-27, especially for cell-culture-adapted CSFV. The combined use of both blocking agents led to a significant reduction of viral growth but was also not able to abolish infection completely. The results obtained in this study showed that both porcine CD46 and heparan sulfates play a major role in the initial steps of CSFV infection. Additional receptors might also play a role for attachment and entry; however, their impact is obviously limited in vitro in comparison to CD46 and heparan sulfates.

  6. 中国猪瘟发生风险定性评估%Qualitative Risk Assessment of Classical Swine Fever Qutbreak in China

    Institute of Scientific and Technical Information of China (English)

    姚文生; 范学政; 王琴; 宁宜宝

    2011-01-01

    为定性评估中国猪瘟发生风险,本研究通过收集整理国内外猪瘟研究资料,运用动物疫病风险分析方法对猪瘟病原特性、传染源、传播途径、易感动物和已采取防控措施效果5个主要风险因素进行定性分析.风险评估认为目前全国范围均0存在猪瘟发生风险,由于实施了猪瘟强制免疫政策,猪群均存在一定的免疫抗体,因此猪瘟大规模流行几率很低,但点状散发流行几率较高.现阶段疫苗免疫仍是中国防控猪瘟的重要手段.%For qualitative risk assessment of classical swine fever(CSF) outbreak in China,this study used the risk analysis method of animal disease to qualitative analyze the pathogenic characteristics, infection sources, transmission patterns, susceptible animals, the effect of prevention and control measures of CSF in China, by analyzing domestic and foreign data of CSF. The results indicated that the outbreak risk of CSF was existing across the country. Due to the implementation of the compulsory vaccination policy, the probability of CSF pandemic is very low, but the local and spotting outbreak is high risk in China. Vaccination is still important to prevent and control CSF at this stage.

  7. 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

  8. 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.

  9. 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.

  10. In vitro adaptation and genome analysis of a sub-subgenotype 2.1c isolate of classical swine fever virus.

    Science.gov (United States)

    Gong, Wenjie; Lu, Zongji; Zhang, Li; Xie, Xiaoming; Jiang, Daliang; Jia, Junjie; Guo, Huancheng; Shi, Jishu; Tu, Changchun

    2016-10-01

    Classical swine fever (CSF) still causes substantial economic losses in the pig industry in China. This study reports the isolation and characterization of a field CSF virus named GD53/2011 from pig kidney tissue collected during a CSF outbreak in Guangdong province, China. Phylogenetic analysis based on the full-length E2 gene sequence revealed that this isolate belongs to CSFV sub-subgenotype 2.1c. To further understand the replication characteristics, GD53/2011 was subsequently adapted in PK-15 cells, and its full-length genome was sequenced. After adaptation in PK-15 cells, the titer of GD53/2011 was significantly increased from 10(3.39) TCID50/ml at passage 6 (F6) to 10(8.50) TCID50/ml at passage 46 (F46) with the peak titer obtained at 48 h post-inoculation. Sequence comparison revealed that the E(rns) gene at passages 6, 15, and 25 of GD53/2011 was identical to that in the original tissue, but one amino acid substitution (S476R) was detected at passages 35 and 46. Furthermore, E2 gene sequences at passages 6, 15, 25, 35, and 46 was found identical to that in the original tissue, indicating that the E2 gene was stable during CSF virus adaptation in PK-15 cells. Full-length protein sequence comparison of GD53/2011 with other 2.1 sub-subgenotype isolates showed that Core and NS5A, rather than E2, are more genetically variable. Taken together, a field CSFV strain GD53/2011 was isolated, fully sequenced, and adapted to high growth titer in PK-15 cells, which might be suitable for future studies on CSFV infection, replication, and vaccine development. PMID:27155669

  11. How to survey classical swine fever in wild boar (Sus scrofa) after the completion of oral vaccination? Chasing away the ghost of infection at different spatial scales.

    Science.gov (United States)

    Saubusse, Thibault; Masson, Jean-Daniel; Le Dimma, Mireille; Abrial, David; Marcé, Clara; Martin-Schaller, Regine; Dupire, Anne; Le Potier, Marie-Frédérique; Rossi, Sophie

    2016-01-01

    Oral mass vaccination (OMV) is considered as an efficient strategy for controlling classical swine fever (CSF) in wild boar. After the completion of vaccination, the presence of antibodies in 6-12 month-old hunted wild boars was expected to reflect a recent CSF circulation. Nevertheless, antibodies could also correspond to the long-lasting of maternal antibodies. This paper relates an experience of surveillance which lasted 4 years after the completion of OMV in a formerly vaccinated area, in north-eastern France (2010-2014). First, we conducted a retrospective analysis of the serological data collected in 6-12 month-old hunted wild boars from 2010 up to 2013, using a spatial Bayesian model accounting for hunting data autocorrelation and heterogeneity. At the level of the whole area, seroprevalence in juvenile boars decreased from 28% in 2010-2011 down to 1% in 2012-2013, but remained locally high (above 5%). The model revealed the existence of one particular seroprevalence hot-spot where a longitudinal survey of marked animals was conducted in 2013-2014, for deciphering the origin of antibodies. Eleven out of 107 captured piglets were seropositive when 3-4 months-old, but their antibody titres progressively decreased until 6-7 months of age. These results suggest piglets were carrying maternal antibodies, few of them carrying maternal antibodies lasting until the hunting season. Our study shows that OMV may generate confusion in the CSF surveillance several years after the completion of vaccination. We recommend using quantitative serological tools, hunting data modelling and capture approaches for better interpreting serological results after vaccination completion. Surveillance perspectives are further discussed. PMID:26810218

  12. New insights on the management of wildlife diseases using multi-state recapture models: the case of classical swine fever in wild boar.

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    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. Complete genome sequence of a novel sub-subgenotype 2.1g isolate of classical swine fever virus from China.

    Science.gov (United States)

    Gong, Wenjie; Zhang, Li; Lu, Zongji; Jia, Junjie; Wang, Meng; Peng, Zhicheng; Guo, Huancheng; Shi, Jishu; Tu, Changchun

    2016-09-01

    Current subgenotype 2.1 isolates of classical swine fever virus (CSFV) play a dominant role in CSF outbreaks in China, and a novel sub-subgenotype 2.1g of CSFV was recently identified, but the complete genome sequence of this new sub-subgenotype has not been reported. In this study, complete genome of 2.1g isolate GD19/2011 collected from Guangdong province of China in 2011 was sequenced. It was found to be 12,298 nucleotides (nt) in length, including a 375-nt 5'UTR, a 11,697-nt opening reading frame (ORF), and a 227-nt 3'UTR. GD19/2011 shared 91.0-93.7 % and 95.6-97.5 % nt and amino acid sequence identity, respectively, with other subgenotype 2.1 isolates. The topology of a phylogenetic tree constructed based on complete genome sequences of GD19/2011 and other CSFV isolates was identical to that obtained with full-length E2 gene sequences, but it was significantly different from those obtained with the 5'UTR and core sequences. Serial passages of GD9/2011 in PK-15 cells generated a highly cell-adapted virus stock with an infectious titer of 10(7.8) TCID50/ml at the 12(th) passage in which two amino acid substitutions, S476R and N2494S, were observed in comparison with the complete polyprotein sequence of the original isolate from kidney tissue, GD19/2011. This is the first report of the complete genome sequence of a 2.1g isolate, and the GD19/2011 isolate will be useful for further analysis of the evolution and virulence of CSFV isolates. PMID:27318930

  14. The influence of between-farm distance and farm size on the spread of classical swine fever during the 1997-1998 epidemic in The Netherlands.

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    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.

  15. Mutual Interference on the Efficacy of Classic Swine Fever and Mycoplasma hyopneumoniae Live Vaccines%猪瘟和猪肺炎支原体活疫苗同时免疫的相互干扰研究

    Institute of Scientific and Technical Information of China (English)

    沈青春; 范学政; 王芳; 王琴; 宁宜宝

    2011-01-01

    Classic swine fever (CSF) and Mycoplasma pneumoniae of swine(MPS) were two common epidemic diseases of swine, and had almost the same first immunization age. In this study, 24 piglets at 30 to 40 days of age were inoculated Mycoplasma hyopneumoniae vaccine, live (RM48 strain) and classic swine fever vaccine, live (ST), both or respectively, to study if there was interference between the two vaccine inoculation. The results indicated that both or individually inoculations did not interfere the efficacy of the two vaccine obviously.%猪瘟和猪支原体肺炎是两种较为常见的猪传染病,首免日龄接近,本试验通过对24头30—40日龄仔猪分别或同时免疫猪支原体肺炎活疫苗(RM48株)和猪瘟活疫苗(传代细胞源),研究其相互之间是否存在免疫干扰。试验结果显示,两种疫苗同时免疫对其各自的近期免疫效力均无明显影响。

  16. 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.

  17. Monitor and analysis of immune antibody on classical swine fever vaccine in Luojiang county%泉州市洛江区猪瘟抗体水平检测效果分析

    Institute of Scientific and Technical Information of China (English)

    庄培德; 张阿娥

    2015-01-01

    结合实验室每年的检测工作,2013-2014年对洛江区辖区内20个生猪规模养殖场和89个散养户的856份猪血清进行猪瘟疫苗免疫抗体检测。结果表明:洛江区猪瘟疫苗免疫抗体合格率呈现上升趋势,规模场猪瘟疫苗免疫抗体合格率明显高于散养户,免疫2次的抗体合格率明显高于1次。抗体检测工作的开展,对制定科学合理的免疫程序,有效防控猪瘟疫情的发生发挥了积极的作用。%Combining with monitoring work in the laboratory every year,from 2013 to 2014,856 serum samples were analyzed for Clas-sical swine fever immune antibody collecting from 20 large-scale pig raising farmers and 89 farmers in Luojiang county. The results showed that there was a ascending annually for antibody qualification rate, antibody qualification rate of large-scale pig raising farmers were higher than that of farmers, antibody qualification rate of twice injection were significantly than ance injection, developing of the antibody monitoring provided scientifical basis for preventing Classical swine fever and formulating rational immune programme on Classical swine fever.

  18. 76 FR 70037 - Importation of Live Swine, Swine Semen, Pork, and Pork Products From Liechtenstein and Switzerland

    Science.gov (United States)

    2011-11-10

    ... we recognize as low risk for classical swine fever (CSF). We are also adding Liechtenstein to the... United States of various animal diseases, including classical swine fever (CSF), swine vesicular disease..., AFRICAN SWINE FEVER, CLASSICAL SWINE FEVER, SWINE VESICULAR DISEASE, AND BOVINE SPONGIFORM...

  19. Classical Swine Fever in Brazil: study for the survey of classical swine fever outbreaks in Brazil from 1978 to 2004/ Peste Suína Clássica no Brasil: estudo para a avaliação dos surtos de peste suína clássica no Brasil de 1978 a 2004

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    Lúcio Ayres Caldas

    2007-10-01

    Full Text Available The programs developed in Brazil with the aim to control and eradicate swine fever provided an opportunity for the survey of Classical Swine Fever (CSF outbreaks. Were concerned CSF official programs, strategies and results, during 26 years. Based in epizootic official data we showed that the number of CSF outbreaks from 1978 to 2004 drastically decreased in all country, although different eradicating strategies were applied in those official programs, especially in fourteen States of “CSF Free Zone”. Were evaluated both CSF official programs: Swine Pests Combat Program (SPCP from 1984 to 1991 and CSF Eradication and Control Program (CSFECP from 1992 to 2004 by the decreasing of CSF outbreaks number. Considering the technical evolution in swine production systems, statistical analysis to compare the ranking of CSF outbreaks in each program was performed by Mann-Whitney test, that showed at 95% confidence level (Table T a significant difference (pOs programas oficiais para o controle e erradicação de pestes suínas forneceram uma oportunidade de levantar o perfil de ocorrência da Peste Suína Clássica (PSC. Independente das estratégias aplicadas durante 26 anos foi demonstrado que o número de surtos de PSC de 1978 até 2004 caiu drasticamente em todo país, especialmente nos quatorze Estados inclusos na “Zona Livre de PSC”. O estudo comparou o número de surtos de PSC durante a vigência do Programa de Combate às Pestes Suínas (PCPS de 1984 a 1991 e o Programa de Controle e Erradicação da PSC (PCEPSC de 1992 a 2004. Considerando a evolução tecnológica nos sistemas de produção de suínos, a diferença nos resultados obtidos após a implementação de cada programa foi avaliada pelo teste estatístico Mann Whitney por meio da ordenação do número de surtos ocorridos. Essa análise demonstrou uma diferença significativa (p< 0,05 entre os programas no nível de confiança de 95% (Tabela T com havia sido sugerido pelo

  20. 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.

  1. 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.

  2. 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.

  3. Towards an improved understanding of African swine fever virus transmission

    NARCIS (Netherlands)

    Cardoso de Carvalho Ferreira, H.

    2013-01-01

    African swine fever is a haemorrhagic disease of swine caused by African swine fever virus (ASFV). Estimates of virus transmission (direct or indirect) parameters for ASFV are necessary in order to model the spread of the virus, and to design more efficient control measures. Results presented on thi

  4. On Effect of Buzhong Yiqi Powder on Immunization Against Classical Swine Fever in Pigs%补中益气散对猪瘟疫苗免疫效果的影响

    Institute of Scientific and Technical Information of China (English)

    彭代国

    2014-01-01

    为了进一步提高猪瘟疫苗的免疫效果,探讨补中益气散对该疫苗的免疫增强作用,该研究以某猪场27头30日龄健康仔猪随机分为3组,对照组和试验1,2组.对照组仅注射猪瘟疫苗;试验1组用补中益气散拌料饲喂一周后注射疫苗;试验2组注射疫苗同时拌料饲喂补中益气散一周,中药用量均按0.2%加入饲料.分别于免疫当天、免疫接种后7,30 d无菌操作采集血样,运用正向间接血凝试验检测血清中的抗体水平.结果表明:补中益气散可显著提高血清中的抗体水平,免疫后30 d免疫保护率维持在88.9%以上,提示补中益气散具有显著增强猪瘟疫苗免疫效果的作用.%The experiment has been designed to investigate the effect of Buzhong Yiqi powder on Classical Swine Fever (SWF) vaccine in order to improve its immune effect .Classical Swine Fever ,which is mainly prevented and controlled by vaccine ,is one of the List A infectious diseases of animals .However ,the im‐mune effect with vaccine is not so good .The experiment has been designed to investigate the immune effect of Buzhong Yiqi powder on Classical Swine Fever vaccine before or after injecting .Twenty seven healthy 30‐day‐old piglets have been selected and divided into 3 groups :experimental group 1 and 2 ,and control group .For the control group ,only Classical Swine Fever vaccine is immunized .For the experimental group 1 ,vaccine is immunized after feeding Buzhong Yiqi powder with the proportion of 0 .2% in feeds for one week .But for the experimental group 2 ,vaccine is immunized ,and Buzhong Yiqi powder with the proportion of 0 .2% in feeds is fed at the same time .Serum antibody level is detected by the method of in‐direct hemagglutination test before and 7 ,30 d after immunization .The results show that serum antibody level is significantly increased after feeding Buzhong Yiqi powder . And the ratio of immunoprotection maintains

  5. 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

  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. 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

  8. 猪瘟病毒Npro基因的克隆表达%Molecular Cloning and Expression of Npro Gene of the Classical Swine Fever Virus

    Institute of Scientific and Technical Information of China (English)

    高斌; 冯励; 李永强; 付晓萍

    2012-01-01

    In order to select an eukaryotic expression vector for Npro protein, and to study the relationship between Npro and major histocompatibility complex ( MHC) at different time point, a full length Npro gene of classical swine fever virus ( CSFV) of Shimen was amplified and cloned by RT-PCR. The results showed that the Npro gene contained 592 bp. The recombinant plasmid and expression vector pcDNA3. 0 were digested by the restriction enzymes Bam H I and Xho I , after the amplified fragments was subcloned into the expression vector pcDNA3. 0, the recombinant plasmid P-Npro was obtained. The insert position, size and reading frame were determined by PCR, restriction digestion and the sequence analysis. The recombinant P-Npro plasmid expressed Npro was used to transfect PK-15 cells in vitro by liposome infection protocol. The results showed that after 24 h and 48 h posttransfeclion, Npro protein was detected by Western-blot analysis with anti-His monoclonal antibody, and it was found that the Npro protein was located.%为了得到一个表达Npro蛋白的真核表达载体,从而为下一步研究不同时间段细胞主要组织相容性复合体( MHC)表达的变化情况,从分子水平上说明Npro与MHC之间的关系,本研究应用反转录聚合酶链式反应(RT-PCR)技术对猪瘟病毒石门毒株Npro基因进行了克降和测序,结果得到了长度为592 bp的目的片段.用BamH Ⅰ和Xho Ⅰ限制性内切酶分别对重组克隆质粒和转移载体pcDNA3.0进行双酶切,回收目的基因DNA片段,将目的基因Npro亚克隆至真核转移载体pcDNA3.0中,经双酶切和序列测定鉴定插入基因和连接方向正确,得到含完整Npro基因的重组载体质粒p-Npro.构建成功的真核表达载体以脂质体介导的转染方法将此重组载体质粒转染PK-15细胞,转染24和48 h后检测表达情况.经Western-blot方法检测表明,此Npro蛋白在PK-15细胞中正确表达.

  9. Evaluation of the risk of classical swine fever (CSF) spread from backyard pigs to other domestic pigs by using the spatial stochastic disease spread model Be-FAST: the example of Bulgaria.

    Science.gov (United States)

    Martínez-López, Beatriz; Ivorra, Benjamin; Ramos, Angel Manuel; Fernández-Carrión, Eduardo; Alexandrov, Tsviatko; Sánchez-Vizcaíno, José Manuel

    2013-07-26

    The study presented here is one of the very first aimed at exploring the potential spread of classical swine fever (CSF) from backyard pigs to other domestic pigs. Specifically, we used a spatial stochastic spread model, called Be-FAST, to evaluate the potential spread of CSF virus (CSFV) in Bulgaria, which holds a large number of backyards (96% of the total number of pig farms) and is one of the very few countries for which backyard pigs and farm counts are available. The model revealed that, despite backyard pigs being very likely to become infected, infections from backyard pigs to other domestic pigs were rare. In general, the magnitude and duration of the CSF simulated epidemics were small, with a median [95% PI] number of infected farms per epidemic of 1 [1,4] and a median [95% PI] duration of the epidemic of 44 [17,101] days. CSFV transmission occurs primarily (81.16%) due to indirect contacts (i.e. vehicles, people and local spread) whereas detection of infected premises was mainly (69%) associated with the observation of clinical signs on farm rather than with implementation of tracing or zoning. Methods and results of this study may support the implementation of risk-based strategies more cost-effectively to prevent, control and, ultimately, eradicate CSF from Bulgaria. The model may also be easily adapted to other countries in which the backyard system is predominant. It can also be used to simulate other similar diseases such as African swine fever.

  10. 9 CFR 94.8 - Pork and pork products from regions where African swine fever exists or is reasonably believed to...

    Science.gov (United States)

    2010-01-01

    ... NEWCASTLE DISEASE, AFRICAN SWINE FEVER, CLASSICAL SWINE FEVER, SWINE VESICULAR DISEASE, AND BOVINE... arrival in the United States to a meat processing establishment operating under Federal meat inspection... issue the foreign meat inspection certificate required by part 327 of chapter III of this title....

  11. Research progress of diagnosis and control of classical swine fever%猪瘟诊断和防制研究进展

    Institute of Scientific and Technical Information of China (English)

    胡慧; 邱昌庆

    2004-01-01

    猪瘟(Classical swine fever,CSF)是严重威胁养猪业、具有重要经济意义的病毒性疾病之一,被国际兽疫局(OIE)列为A类的15种传染病之一。其特征是小血管壁变性,内脏器官多发性出血、坏死和梗塞。该病的病原是猪瘟病毒(CSFV),CSFV在分类上属于黄病毒科(Flaviviridae)瘟病毒属(Pesti-virus),同属的还有牛病毒性腹泻病毒(Bovine viral diarrhea virus,BVDV)和绵羊边界病病毒(Border disease virus,BDV),

  12. 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.

  13. 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.

  14. Impacts of Pig Management and Husbandry Farmers Towards Classical Swine Fever Transmission in West Timor Indonesia (DAMPAK MANAJEMEN DAN CARA BETERNAK BABI TERHADAP PENULARAN PENYAKIT CHOLERA BABI DI TIMOR BARAT

    Directory of Open Access Journals (Sweden)

    Petrus Malo Bulu

    2015-05-01

    Full Text Available Classical swine fever (CSF is a serious and highly infectious viral disease of domestic pigs and wildboar, which is caused by a single stranded RNA pestivirus. A cross sectional study was carried out onsmall-holder pig farmers in West Timor, in the province of East Nusa Tenggara, Indonesia. The objectiveof this study was to describe the management, husbandry and trading practices adopted by pig farmers inWest Timor. A questionnaire survey was administered to the owners of these pigs (n = 240 to gatherinformation from farmers in order to understand management and husbandry practices in the region. Theresults of the questionnaire highlighted the lack of implementation of biosecurity measures by smallholderfarms in West Timor, which has the potential to increase the risk of their pigs to CSF, as well as toother diseases.

  15. A Survey of Wild Boars in Guangxi for Infection of Classical Swine Fever%广西野猪猪瘟病毒感染情况的调查报告

    Institute of Scientific and Technical Information of China (English)

    陈凤莲; 马玲; 潘汉世; 黄红梅; 孙建华; 陈忠伟; 吴健敏

    2007-01-01

    作者报道采用RT-PCR和ELISA方法检测猪瘟病毒在野猪身上的感染情况.采集广西5个地市28份野猪脾淋组织作病毒检测,设计针对猪瘟(classical swine fever,CSF)病毒的特异性引物CSFVE2,进行RT-PCR检测,所检样品结果全呈猪瘟阴性;同时,运用酶联免疫吸附测定(ELISA)试剂盒检测以上样品,结果也都呈阴性.这一结果初步表明所检测的广西5个地区的野猪没有感染猪瘟病毒.

  16. Implementation and validation of an economic module in the Be-FAST model to predict costs generated by livestock disease epidemics: Application to classical swine fever epidemics in Spain.

    Science.gov (United States)

    Fernández-Carrión, E; Ivorra, B; Martínez-López, B; Ramos, A M; Sánchez-Vizcaíno, J M

    2016-04-01

    Be-FAST is a computer program based on a time-spatial stochastic spread mathematical model for studying the transmission of infectious livestock diseases within and between farms. The present work describes a new module integrated into Be-FAST to model the economic consequences of the spreading of classical swine fever (CSF) and other infectious livestock diseases within and between farms. CSF is financially one of the most damaging diseases in the swine industry worldwide. Specifically in Spain, the economic costs in the two last CSF epidemics (1997 and 2001) reached jointly more than 108 million euros. The present analysis suggests that severe CSF epidemics are associated with significant economic costs, approximately 80% of which are related to animal culling. Direct costs associated with control measures are strongly associated with the number of infected farms, while indirect costs are more strongly associated with epidemic duration. The economic model has been validated with economic information around the last outbreaks in Spain. These results suggest that our economic module may be useful for analysing and predicting economic consequences of livestock disease epidemics. PMID:26875754

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. 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

  2. 猪瘟耐热保护剂活疫苗(兔源)免疫效果监测%Surveillance of the Immune Effect of Live Classical Swine Fever Vaccine(Rabbit-Origin)with Heat-resistant Protectants

    Institute of Scientific and Technical Information of China (English)

    栗新

    2014-01-01

    In order to know the compulsory immunization effects of swine fever vaccine with heat-resistant protectants in natural conditions,2140 piglet serum samples were collected from 50 intensive pig farms and 380 free-ranging pig holders after concentrated immunizations in spring and autumn for immune-surveillance. Results showed that the positive rate of classical swine fever antibody was 67.3%after spring immunization,with 79.8%in intensive farms and 56.3%in free-ranging holders;the positive rate of swine fever antibody was 69.1%after autumn immunization,with 70.1%by vaccine B(81.6%in intensive farms and 61.3%in free-ranging holders),and 65.8%by vaccine C(78.5%in inten-sive farms and 51.2%in free-ranging holders). The antibody dispersion of spring immunization was 37.5%in average, with 25.5%in intensive farms and 48.2%in free-ranging holders;the antibody dispersion of autumn immunization with vaccine B was 31.4%,with 28.4%in intensive farms and 35.6%in free-ranging holders;and the antibody dispersion of autumn immunization with vaccine C was 41.5%,with 42.1%in intensive farms and 41.2%in free-ranging holders.%为了解掌握猪瘟耐热保护剂活疫苗在自然状态下的强制免疫效果,在春秋二季集中免疫之后,跟踪监测了50个规模猪场和380个散养户仔猪血样2140份。监测结果发现:春防猪瘟样品抗体监测阳性率为67.3%,其中规模场79.8%,散户56.3%;秋防猪瘟样品抗体监测阳性率为69.1%,其中,免疫B苗的抗体阳性率为70.1%(规模场81.6%,散户61.3%),C苗的抗体阳性率为65.8%(规模场78.5%,散户51.2%)。春防抗体离散度平均37.5%,其中规模场25.5%,散户48.2%;秋防B苗接种的抗体离散度31.4%,其中规模场28.4%,散户35.6%;秋防C苗接种的抗体离散度41.5%,其中规模场42.1%,散户41.2%。

  3. 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.

  4. Epidemic Status and Proposals for Prevention and Control of Classical Swine Fever in China%我国猪瘟流行现状与防控措施建议

    Institute of Scientific and Technical Information of China (English)

    姚文生; 范学政; 王琴; 宁宜宝

    2011-01-01

    为了解当前我国猪瘟流行现状,收集整理猪瘟流行病学调查资料,分析归纳出我国猪瘟临床特征是以非典型猪瘟或温和型猪瘟以及妊娠母猪繁殖障碍为主要表现形式,急性猪瘟病例较少;流行特点是点状散发流行,季节性不明显,持续感染、隐性感染、混合感染和免疫失败现象普遍存在。根据其流行现状,提出降低其发生几率的五点防控措施建议:实行种猪群净化措施、加强免疫监测、加强病原监测、发展规模化养殖和开展野猪猪瘟病毒感染情况调查。%In order to get the facts of the current epidemic status of classical swine fever (CSF) in China, this study was designed to summarize disease characteristics of CSF by collecting and researching epidemiological data of CSF. The results indicated that CSF cases mainly showed atypical or mild symptom, breeding disorder and few acute cases. CSF was sporadic in spotting areas, and occurred in any season, and some symptoms such as persistent infection, polyinfection, inapparent infection and immunization failure were prevalent clinically. Accordin$ to its epidemic status, it was proposed to implement the clearance scheme of CSFV in breeding herd, strengthen the immune monitoring, enhance the pathogen monitoring, develop the scale - breeding and investigate the prevalence of CSF in wild boar in China.

  5. 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

  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. 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

  8. Quantification of airborne African Swine Fever virus after experimental infection

    NARCIS (Netherlands)

    Carvalho Ferreira, de H.C.; Weesendorp, E.; Quak, S.; Stegeman, J.A.; Loeffen, W.L.A.

    2013-01-01

    Knowledge on African Swine Fever (ASF) transmission routes can be useful when designing control measures against the spread of ASF virus (ASFV). Few studies have focused on the airborne transmission route, and until now no data has been available on quantities of ASF virus (ASFV) in the air. Our aim

  9. Hemophagocytic syndrome in classic dengue fever

    Directory of Open Access Journals (Sweden)

    Sayantan Ray

    2011-01-01

    Full Text Available A 24-year-old previously healthy girl presented with persistent fever, headache, and jaundice. Rapid-test anti-dengue virus IgM antibody was positive but anti-dengue IgG was nonreactive, which is suggestive of primary dengue infection. There was clinical deterioration during empiric antibiotic and symptomatic therapy. Bone marrow examination demonstrated the presence of hemophagocytosis. Diagnosis of dengue fever with virus-associated hemophagocytic syndrome was made according to the diagnostic criteria of the HLH 2004 protocol of the Histiocyte Society. The patient recovered with corticosteroid therapy. A review of literature revealed only a handful of case reports that showed the evidence that this syndrome is caused by dengue virus. Our patient is an interesting case of hemophagocytic syndrome associated with classic dengue fever and contributes an additional case to the existing literature on this topic. This case highlights the need for increased awareness even in infections not typically associated with hemophagocytic syndrome.

  10. 规模化猪场种猪猪瘟免疫方式和剂量的探讨%Immunity Method and Dose of Breeding Pigs against Classical Swine Fever Virus (CSFV) on Large-scale Pig Farms

    Institute of Scientific and Technical Information of China (English)

    罗才庆

    2012-01-01

      对福建某公司2010年、2011年“一刀切”免疫(一年春、秋各免疫1次,每头每次免疫剂量1.5头份猪瘟兔化弱毒脾淋苗)的4561份种猪血清样品采用 HerdChek 猪瘟抗体检测试剂盒进行抗体检测,评价种猪猪瘟免疫效果,保证猪瘟免疫合格率达到80%以上,为规模化猪场种猪进行猪瘟免疫提供科学依据.结果显示:2010年、2011年种猪抗体检测合格率为86.70%、84.32%,对抗体不合格种猪再一次加强免疫后抗体检测总合格率91.28%、89.74%.由此表明:种猪猪瘟全群采用“一刀切”免疫猪瘟兔化弱毒脾淋苗,可以起到良好的免疫效果%  To evaluate the status of the immunity in breeding pigs against classical swine fever virus (CSFV), en-sure that the satisfactory levels of immunity was higher than 80% and provide a scientific basis for the immunity in breeding pigs against CSFV on the large-scale pig farms, 4561 serum samples from a large-scale pig farms in Fu-jian were collected and tested by HerdChek ELISA , which were immunized by "impose uniformity" method. The breeding pigs immunized with the HCLV bovine testis Lymph tissue origin vaccine at dose of 1.5ml/sow/time, ev-ery year twice on spring and autumn respectively. The results showed that the satisfactory levels of antibodies a-gainst CSFV in 2011 and 2012 were 86.70% and 84.32%, respectively. After immunizing once again to the unsat-isfactory levels of antibodies of breeding pigs, the total satisfactory levels of antibodies were 91.28% and 89.74%, respectively. The primary result reveals that the breeding herd immunized with the HCLV bovine testis Lymph tis-sue origin vaccine by "impose uniformity" method could play a good immune effect.

  11. 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

  12. 猪瘟病毒野毒株RT-LAMP可视化检测方法的建立%Visualized detection of wild-type classical swine fever virus using RT-LAMP

    Institute of Scientific and Technical Information of China (English)

    张兴娟; 孙元; 刘大飞; 仇华吉

    2009-01-01

    To develop a rapid and practical method to differentiate wild-type strains of classical swine fever virus (CSFV) and the attenuated C-strain, a reverse transcription-loop-mediated isothermal amplification (RT-LAMP) assay was established with a set of primers based on NS5B gene sequence. The viral cDNA generated by reverse transcription was amplified with Bst DNA polymerase at a constant temperature of 62 ℃, and the products could be visualized under the UV light with SYBR Green I dye. The RT-LAMP was able to detect different genotypes of wild-type CSFV strains, but not for the C-strain, bovine viral diarrhea virus or other swine viruses. The detection limit of the RT-LAMP assay was 2.5 TCID_(50) of CSFV, comparable to the sensitivity of the real-time RT-PCR. The agreement rate between RT-LAMP and the real-time RT-PCR or the primer-probe energy transfer real-time PCR was 100 % or 98.4 % in detecting 126 samples. Thus, the assay is a rapid, sensitive, simple and practical method for the detection of wild-type CSFV in the field.%本研究旨在建立一种可视化检测猪瘟病毒(CSFV)野毒株的反转录.环介导等温扩增方法(RT-LAMP).根据CSFV的NS5B基因序列设计一套RT-LAMP引物,以样品的cDNA为模板,利用Bsf DNA聚合酶,在62℃恒温条件下进行扩增,扩增产物中加入sYBR Green I染料直接或在紫外光下观察判定扩增结果.该方法可检测出不同基因型的CSFV厂野毒株,其检出极限为2.5 TCID_(50)的CSFV,与实时荧光定量RT.PCR方法的敏感性相当;特异性试验表明,该方法对猪瘟免化弱毒疫苗株(HCLV)、牛病毒性腹泻病毒以及其它常见猪源病毒均无扩增反应;通过对126份不同样品进行检测比较,该方法与实时荧光定量RT-LAMP检测方法的符合率达100%.与引物.探针能量转移PCR方法的符合率为98.4%.该方法无需特殊仪器,是一种适用于基层的快速、简便的CSFV野毒鉴别检测方法.

  13. Classical Swine Fever Virus-Rluc Replicons

    DEFF Research Database (Denmark)

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

    replication were constructed and these deletions were swapped with an in-frame insertion of the Renilla luciferase (Rluc) sequence. RNA transcripts from these replicons should be translated as a single functional open reading frame. Full-genome cDNA’s (~10-12,3 kb) were amplified from the BACs using a stable...

  14. 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.

  15. 9 CFR 98.38 - Restrictions on the importation of swine semen from the APHIS-defined EU CSF region.

    Science.gov (United States)

    2010-01-01

    ...) and 94.10(a) of this chapter as one in which classical swine fever is known to exist, except for the... because of the detection of classical swine fever in domestic swine, from the time of detection until the... classical swine fever in wild boar, from the time of detection until the designation of the zone as...

  16. 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.

  17. Peste suína clássica: ação térmica da amostra chinesa Porto Alegre (CPA em coelhos Classical swine fever: thermal reaction in rabbits to the chinese-Porto Alegre strain

    Directory of Open Access Journals (Sweden)

    Telmo Vidor

    1995-01-01

    Full Text Available Foram avaliadas a temperatura normal do coelho e sua reação térmica após inoculação com a amostra Chinesa Porto Alegre (CPA do vírus da Peste Suína Clássica (PSC, sob três condições de temperatura ambiental. Os resultados mostraram que a temperatura normal do coelho aumenta com a elevação da temperatura ambiental (PRectal temperatures of normal rabbits inoculated with different dilutions of a vaccine prepared with Chinese-Porto Alegre (CPA strain of classical swine fever virus, were evaluated under 3 different environmental temperatures. Temperatures of normal un-vaccinated rabbits increased significantly when environmental temperature increased (P<0.001. At environmental temperatures of 12.82 ± 1.29°C, 20.65 ± 1.79°C, and 28.24 ± 2.09°C me mean rectal temperatures were 39.53°C, 39.65°C and 39.92°C, respectively. Temperatures of me vaccinated rabbits also increased significantly when environmental temperature increased (P<0.001, but did not vary with different vaccine dilutions. At environmental temperatures of 12.82 ± 1.29°C, 20.65 ±1.79°C and 28.24 ± 2.09°C, the mean higher rectal temperature were 41.17°C, 41.24°C and 41.47°C, respectively. Within a 95% confidence interval was determined that, under the 3 environmental temperatures, the rectal temperatures equal to 40.60°C, 40.67°C and 40.90°C or higher, indicated a thermal reaction to the vaccine. In vaccinated rabbits, the mean thermic rise was of 1.59°C and there were no significant differences at different environmental temperatures or virus dilutions. Within a 95% confidence interval was determined that a rise of 1.06°C or higher indicated a specific reaction to the vaccine. The rise in temperature started 24 hours after the inoculation. This time was delayed when virus dilutions decreased (P<0.001, but did not vary with different environmental temperatures. The sensitivity and specificity of the thermic reaction was evaluated by the challenge test. By

  18. 77 FR 74555 - Importation of Live Swine, Swine Semen, Pork, and Pork Products; Estonia, Hungary, Slovakia, and...

    Science.gov (United States)

    2012-12-17

    ...-risk region for classical swine fever. We have determined that the 40-day holding period for swine... to prevent the introduction into the United States of various animal diseases, including classical swine fever (CSF), foot-and-mouth disease (FMD), swine vesicular disease (SVD), and rinderpest....

  19. Comparison of immune effect on spleen and lymph tissue and cell line origin classical swine fever vaccine in field%猪瘟脾淋苗和传代细胞苗田间免疫效果比较试验

    Institute of Scientific and Technical Information of China (English)

    洪江庭

    2015-01-01

    Three vaccines were used to compare immune effect on spleen and lymph tissue and cell line origin classical swine fever vaccine. Forty-five 30-day-old piglets were randomly selected and divided into 3 groups in a scale farm in Xiamen, meanwhile first immunization was carried out, second immunizationafter28 days, group A used spleen and lymph tissue origin classical swine fever vaccine from CQ and group B used spleen and lymph tissue origin vaccine from CD, while group C used cell line origin classical swine fever vaccine from JX, through regular tracking of antibody level to evaluate the immune effect. The results showed: The anti-body positive rate in group C herds was the highest on the 38thday after second immunization, with a significant difference in group A herds.%为比较猪瘟脾淋苗和传代细胞苗的免疫效果,在厦门市同安区某规模猪场,选用代号为CQ、CD和JX 3个厂家生产的猪瘟脾淋苗和传代细胞苗进行免疫效果试验。随机选取45头30日龄断乳仔猪,分为3组,30日龄首免,首免后28 d二免,A组免疫接种CQ厂家的猪瘟脾淋苗,B组免疫接种CD厂家的猪瘟脾淋苗,C组免疫接种JX厂家的猪瘟细胞传代苗,通过定期跟踪3组猪群血清中的抗体水平,评估疫苗的免疫效果。结果显示:3组猪群二免后7d前免疫抗体抗体水平和阳性率无显著差异,38 d后才出现免疫抗体水平和阳性率显著差异,以C组猪群的抗体阳性率最高,A组猪群的抗体阳性率最低。

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

    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

      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.%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.

  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. Development of an Alternative Potency Test Method for Classical Swine Fever Live Vaccine%猪瘟活疫苗效力检验替代方法的研究

    Institute of Scientific and Technical Information of China (English)

    王海光; 林旭埜; 张毓金; 范学政; 徐璐; 王琴; 赵启祖; 丁家波; 宁宜宝; 赖月辉; 吴文福; 王芳; 刘灿; 张文利; 黄秋雪; 陈坚

    2015-01-01

    目前,我国猪瘟活疫苗效力检验最常用的方法是测定猪瘟疫苗中病毒的兔体感染量( RID),但是用该方法易受到检验兔品种、个体和饲养环境的影响。为了探索一种不依赖动物的疫苗效力检验新方法,本研究将待检猪瘟活疫苗系列稀释后分别接种易感细胞,使用抗原捕获ELISA、RT-nestPCR和RT-PCR三种方法检测不同稀释度疫苗中活病毒在感染细胞后增殖的子代病毒,计算疫苗病毒的最高细胞感染剂量,建立了猪瘟疫苗病毒的细胞感染量( CID)的效力检验方法。结果显示:疫苗中活病毒粒子越多,CID就越高;对不同类型猪瘟疫苗的检测结果表明,该方法适用于传代细胞源和细胞源猪瘟活疫苗的效力效检。使用CID和RID两种检测方法同时对12批猪睾丸传代细胞源(传代细胞源)和3批牛睾丸原代细胞源(细胞源)猪瘟活疫苗进行了比对效检,结果表明,用CID测定方法检验,12批猪瘟活疫苗(传代细胞源)每头份均含105 CID,3批猪瘟活疫苗(细胞源)每头份含量均为104 CID;用兔子感染体温测定法,12批猪瘟活疫苗(传代细胞源)每头份含量在2.6×104~3.0×104 RID之间,3批猪瘟活疫苗(细胞源)每头份含7.0×103~8.0×103 RID。试验证明:本实验室建立的CID检测结果与现有质量标准RID的结果存在良好的相关性,能够较好反映疫苗中活病毒的含量,有望成为RID的替代方法。%The potency detection method of C-strain vaccine based on classical swine fever virus rabbit infection dose( RID) is widely used in China, however, this method is greatly influenced by bread,individual difference and housing environment. In order to establish an alternative potency test strategy avoid using experimental animals, the permissive cell was inoculated with serial diluted vaccine, and then the antigen-capture ELISA, RT-nestPCR and

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

    DEFF Research Database (Denmark)

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

    2016-01-01

    African swine fever (ASF) is a notifiable infectious disease with a considerable impact on animal health and is currently one of the most important emerging diseases of domestic pigs. ASF was introduced into Georgia in 2007 and subsequently spread to the Russian Federation and several Eastern...... European countries. Consequently, there is a non-negligible risk of ASF spread towards Western Europe. Therefore it is important to develop tools to improve our understanding of the spread and control of ASF for contingency planning. A stochastic and dynamic spatial spread model (DTU-DADS) was adjusted...

  4. 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

  5. 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

  6. CSFV和PRRSV二联RT-PCR检测方法的建立%Establishment of Double RT - PCR for Detection of Classical Swine Fever and Porcine Reproductive and Respiratory Syndrome Virus

    Institute of Scientific and Technical Information of China (English)

    王开; 裴志花; 李菲

    2011-01-01

    参照GenBank中猪瘟病毒(CSFV)和猪繁殖与呼吸障碍综合征病毒(PRRSV)基因保守序列,设计2对特异}l物,通过对最佳反应条件的优化,建立了CSFV和PRRSV的二联RT-PCR检测方法,该方法可同时扩增得到2条与试验设计相符的443 bp(CSFV)和246 bp(PRRSV)特异性条带.应用该二联RT-PCR方法检测猪细小病毒(PPV)、猪伪狂犬病毒(PRV)、牛病毒性腹泻病毒(BVDV)结果均为阴性,证明该方法有良好的特异性.将已知阳性病毒PCR模板最高稀释倍数作为PCR的敏感度,结果表明该二联RT-PCR体系扩增的敏感度为10-3,可对CSFV和PRRSV单个或混合感染的临床样品进行快速鉴别诊断.%According to the gene sequences in GenBank of swine fever virus (CSFV) and porcine reproductive and respiratory syndrome virus(PRRSV), two pairs of specific primers were designed for amplifying the two specific fragments of CSFV and PRRSV. After optimization of annealing temperature and primers concentrations, a double RT- PCR was established for simultaneous detection of the two viruses, and two specific bands of CSFV 443 bp and PRRSV 246 bp were detected. Porcine parvovirus (PPV), porcine pseudorabies virus (PRV) and bovine viral diarrhea virus (BVDV) were detected by the double RT- PCR, and the results were all negative, showing that this method has good specificity. The maximum dilution of template of known viruses for positive PCR was defined as the sensitivity of PCR, and the results showed that the sensitivity of double RT- PCR was 10-3. Positive samples were detected through double PCR, and the results showed that the method could be used to effectively detect and differentiate CSFV and PRRSV single or co-infection infected in clinical samples.

  7. Hemophagocytic syndrome in classic dengue fever

    OpenAIRE

    Sayantan Ray1,*; Supratip Kundu; Manjari Saha; Prantar Chakrabarti

    2011-01-01

    A 24-year-old previously healthy girl presented with persistent fever, headache, and jaundice. Rapid-test anti-dengue virus IgM antibody was positive but anti-dengue IgG was nonreactive, which is suggestive of primary dengue infection. There was clinical deterioration during empiric antibiotic and symptomatic therapy. Bone marrow examination demonstrated the presence of hemophagocytosis. Diagnosis of dengue fever with virus-associated hemophagocytic syndrome was made according to the diagnost...

  8. 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

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

    Science.gov (United States)

    Halasa, Tariq; Bøtner, Anette; Mortensen, Sten; Christensen, Hanne; Toft, Nils; Boklund, Anette

    2016-09-25

    African swine fever (ASF) is a notifiable infectious disease with a considerable impact on animal health and is currently one of the most important emerging diseases of domestic pigs. ASF was introduced into Georgia in 2007 and subsequently spread to the Russian Federation and several Eastern European countries. Consequently, there is a non-negligible risk of ASF spread towards Western Europe. Therefore it is important to develop tools to improve our understanding of the spread and control of ASF for contingency planning. A stochastic and dynamic spatial spread model (DTU-DADS) was adjusted to simulate the spread of ASF virus between domestic swine herds exemplified by the Danish swine population. ASF was simulated to spread via animal movement, low- or medium-risk contacts and local spread. Each epidemic was initiated in a randomly selected herd - either in a nucleus herd, a sow herd, a randomly selected herd or in multiple herds simultaneously. A sensitivity analysis was conducted on input parameters. Given the inputs and assumptions of the model, epidemics of ASF in Denmark are predicted to be small, affecting about 14 herds in the worst-case scenario. The duration of an epidemic is predicted to vary from 1 to 76days. Substantial economic damages are predicted, with median direct costs and export losses of €12 and €349 million, respectively, when epidemics were initiated in multiple herds. Each infectious herd resulted in 0 to 2 new infected herds varying from 0 to 5 new infected herds, depending on the index herd type. PMID:27599924

  10. "猪瘟和非洲猪瘟的综合防治措施"专栏(三)影响猪瘟流行地区疫苗成功接种的关键因素%Factors critical for successful vaccination against classical swine fever in endemic areas

    Institute of Scientific and Technical Information of China (English)

    S.Suradhat; S.Damrongwmanapokin; R.Thanawongnuwech; 高枫; 舒畅

    2009-01-01

    猪瘟(Classical Swine Fever,CFS)又称猪霍乱,由猪瘟病毒(CSFV)引起,是能给全球养猪业造成严重经济损失的最重要的病毒性疾病之一.在过去的5年中,多项用于测定猪细胞免疫(Cell-Mediated Immunity,CMI)的技术与其他常规技术一起,被用来研究可影响猪瘟病毒特异性免疫诱导的因素.从一系列试验获得的资料证明,细胞免疫应答可提供抗猪瘟感染的保护性免疫.尽管业已证实商用改良型猪瘟活疫苗能够诱导免疫猪产生完全的保护,但包括母源免疫、首次免疫年龄、免疫接种方案和其他病原体引起的并发症等多种因素,均会严重影响猪瘟疫苗在田闻的免疫效果.

  11. 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.

  12. African swine fever among slaughter pigs in Mubende district, Uganda.

    Science.gov (United States)

    Muwonge, Adrian; Munang'andu, Hetron M; Kankya, Clovice; Biffa, Demelash; Oura, Chris; Skjerve, Eystein; Oloya, James

    2012-10-01

    Owing to frequent reports of suspected outbreaks and the presence of reservoir hosts and vectors (warthogs, bushpigs and O. moubata ticks), African swine fever (ASF) is believed to be an endemic disease in Uganda. There have, however, been very few studies carried out to confirm its existence in Uganda. This study was carried out to describe the prevalence of ASF based on pathologic lesions and analysis of serum samples from slaughtered pigs during a suspected outbreak in the Mubende district of Uganda. The study was based on visits to 22 slaughterhouses where individual pigs were randomly selected for a detailed ante-mortem and post-mortem inspections. Sera were also collected for laboratory analysis. A total of 997 pigs (53.7% male and 46.3% female) were examined for lesions suggestive of ASF and sero-positivity of sera for ASF antibodies. The sera were tested using enzyme-linked immunosorbent assay (ELISA) and positive samples were further confirmed with an immunoblot assay. The results showed that 3.8% (38/997) of the pigs examined had clinical signs and post-mortem lesions suggestive of ASF. Two of 997 (0.2%) sera analysed were positive for ASF antibodies. Of the sub-counties investigated, Bagezza (12%) and Kiyuni (11%) had the highest prevalence of lesions suggestive of ASF based on ante- and post-mortem examination results, while Mubende town council (1.7%) had the lowest. This study found a low number of pigs (3.8%) with lesions suggestive of ASF at slaughter and an even lower number of pigs (0.2%) that were seropositive at slaughter, however a significantly higher number of pigs were slaughtered during the outbreak as a strategy for farmers to avoid losses associated with mortality.

  13. 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...

  14. 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

  15. African swine fever virus excretion patterns in persistently infected animals: A quantitative approach

    NARCIS (Netherlands)

    Carvalho Ferreira, de H.C.; Weesendorp, E.; Elbers, A.R.W.; Bouma, A.; Quak, S.; Stegeman, J.A.; Loeffen, W.L.A.

    2012-01-01

    The continuing circulation of African swine fever (ASF) in Russia and in the Trans-Caucasian countries has led to increased efforts in characterizing the epidemiology of ASF. For a better insight in epidemiology, quantitative data on virus excretion is required. Until now, excretion data has mainly

  16. African Swine Fever Virus p72 Genotype IX in Domestic Pigs, Congo, 2009

    Science.gov (United States)

    Anchuelo, Raquel; Pelayo, Virginia; Poudevigne, Frédéric; Leon, Tati; Nzoussi, Jacques; Bishop, Richard; Pérez, Covadonga; Soler, Alejandro; Nieto, Raquel; Martín, Hilario; Arias, Marisa

    2011-01-01

    African swine fever virus p72 genotype IX, associated with outbreaks in eastern Africa, is cocirculating in the Republic of the Congo with West African genotype I. Data suggest that viruses from eastern Africa are moving into western Africa, increasing the threat of outbreaks caused by novel viruses in this region. PMID:21801650

  17. Using an Indirect Immunofluorescence Assay for Evaluating the Efficacy of Live Classical Swine Fever Virus Vaccine (C Strain)%用间接免疫荧光检测方法评价猪瘟兔化弱毒活疫苗效力的研究

    Institute of Scientific and Technical Information of China (English)

    戴志红; 蒋卉; 李翠; 王晓卉; 张秀英; 王在时

    2014-01-01

    为用体外试验方法评价猪瘟兔化弱毒活疫苗效力,以猪瘟病毒抗体(兔源)为一抗、荧光素标记羊抗兔IgG 为二抗,建立了CSFV兔化弱毒株的间接免疫荧光检测方法( IFA)。特异性试验表明,用该IFA方法检测CSFV兔化弱毒株接种的RK细胞为阳性,而检测伪狂犬病毒、猪细小病毒病、牛病毒性腹泻/粘膜病毒接种的RK细胞均为阴性。 CSFV兔化弱毒株和活疫苗的兔体感染量( RID)用兔体测定,半数组织感染量( TCID50)用IFA测定,拟合RID与TCID50的线性回归方程,确定1RID/mL=( TCID50/0.1mL+200)/12。%Using the antibody against CSFV (C strain) as the primary antibody and the FITC labeled goat anti-rabbit IgG as the second antibody, an indirect immunofluorescence assay was developed to evaluate the efficacy of live classical swine fever virus vaccine (C strain). The IFA showed positive result in detection RK cells inoculated with CSFV (C strain), but negative results in detection RK cells inoculated with pseudorabies virus, porcine parvovirus and bovine viral diarrhea-mucosal virus. Rabbit infection dose ( RID) tested with rabbits and 50% tissue culture infective dose (TCID50) tested with IFA in CSFV (C strain) and vaccine were both carried out. The linear regression equation fitting the TCID50over RID was conducted, and the result is that 1RID/mL= (TCID50/0.1mL+200)/12.

  18. 猪瘟病毒Taqman实时定量RT-PCR检测方法的建立和临床应用%Development and clinical application of Taqman real-time RT-PCR assay for detection of classical swine fever virus

    Institute of Scientific and Technical Information of China (English)

    毛立; 李文良; 李彬; 江杰元

    2012-01-01

    According to the conservative sequences located on the 5' untranslated region (5'-UTR) of classical swine fever virus(CSFV) ,a pair of specific primers and Taqman probe were designed and synthesized respectively, and a Taqman real-time fluorescent quantitative reserve-transcribed polymerase chain reaction (real-lime RT-PCR) for detecting the CSFV was established in this study. Test results showed that the method had a detection limit of 10 copies of target RNA per reaction, and there was a good linear relationship between Ct value and copy numbers in diluted samples. The variation between batches was less than 1% . The RNA of porcine reproductive and respiratory syndrome virus,bovine viral diarrhea virus were detected by the Taqman RT-PCR,and the results were all negative. The CSFV-positive rate was 71. 9% in 192 samples collected from Jiangsu and Xinjiang areas. Real-time RT-PCR detection showed that the different organs of swine including hearts, lungs, livers, kidneys, brains, spleens,lymph nodes and ascites were CSFV-positive, indicating thai the method were more sensitive and effective than traditional RT-PCR.%根据猪瘟病毒5’非编码区(5’-UTR)设计特异性引物和Taqman探针,建立Taqman实时定量RT-PCR检测猪瘟病毒法.检测结果显示,该方法的灵敏度为1μl 10拷贝,在病毒拷贝数为1μl 108~101时,循环数(Ct)值与拷贝数对数呈现较好的线性关系,且重复性好,批间变异系数小于1%.用该方法检测猪繁殖与呼吸综合征病毒、牛病毒性腹泻病毒,结果均为阴性.用该方法检测采集自江苏和新疆的192份组织和血清样品,猪瘟病毒阳性率为71.9%;检测感染猪的不同脏器,发现在心、肺、肝、肾、脑、脾脏、淋巴结、腹水中均可以检测到猪瘟病毒,与常规RT-PCR方法相比,该方法敏感性更高.该方法的建立为猪瘟病毒的流行病学调查和定量提供了有效手段.

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

    DEFF Research Database (Denmark)

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

    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 c...

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

    DEFF Research Database (Denmark)

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

    recombination into Bacterial Artificial Chromosomes (BAC) clones, containing the full-length Paderborn sequence under the transcriptional control of a T7 promoter and a selection marker in place of the IRES. RNA transcripts were produced in vitro and electroporated into porcine PK15 cells. Rescued mutant...

  1. 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

    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...

  2. 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...

  3. 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...

  4. Evaluation of the risk factors contributing to the African swine fever occurrence in Sardinia, Italy

    OpenAIRE

    Martínez-López, Beatriz; Perez, Andres M.; Feliziani, Francesco; Rolesu, Sandro; Mur, Lina; José M. Sánchez-Vizcaíno

    2015-01-01

    This study assesses the relation between hypothesized risk factors and African swine fever virus (ASFV) distribution in Sardinia (Italy) after the beginning of the eradication program in 1993, using a Bayesian multivariable logistic regression mixed model. Results indicate that the probability of ASFV occurrence in Sardinia was associated to particular socio-cultural, productive and economical factors found in the region, particularly to large number of confined (i.e., closed) farms (most of ...

  5. 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 superinfection in animals, especially in the absence of IFN-α, which might be associated with the lack of innate immune mechanisms.

  6. 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, especially in the absence of IFN-α, which might be associated with the lack of innate immune mechanisms. PMID:26919741

  7. 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, especially in the absence of IFN-α, which might be associated with the lack of innate immune mechanisms. PMID:26919741

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

    OpenAIRE

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

    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 boa...

  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. 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.

  11. DYNATICS OF MATERNAL ANTIBODIES AGAINST CLASSICAL SWINE FEVER IN NATIVE SICHUAN-TIBET BLACK PIGS AND LANDRACE PIGS%川藏黑猪与长白猪仔猪猪瘟母源抗体消长规律比较研究

    Institute of Scientific and Technical Information of China (English)

    于吉锋; 李江凌; 王文贵; 廖党金; 魏甬; 李兴玉; 林毅; 叶健强

    2015-01-01

    In order to better understand immunization protocol of classical swine fever in native Sichuan-Tibet black pigs and imported Landrace pigs, maternal antibodies of piglets were monitored at day 0, 1, 4, 7, 10, 20, 25, 30 and 35 by the blocking ELISA. There were no maternal antibodies detected in piglets born to Sichuan-Tibet black sows and Landrace sows before suckling. However, the maternal antibodies were titrated to be >210 or 28.2 in one-day old piglets born to Sichuan-Tibet black sows or Landrace sows, respectively. At day 4 and 7, the maternal antibody titers were >210 in Sichuan-Tibet black piglets while the titers were 28.4 and 27.4 in Landrace piglets. Afterwards, the titers declined to 24.2 in 35 days-old Sichuan-Tibet black piglets and to 24.0 in Landrace piglets. Obviously, the maternal antibodies dropped faster in Landrace piglets than Sichuan-Tibet black piglets. In conclusion, signifi cant differences in titers and duration of maternal antibodies were detected between Sichuan-Tibet black piglets and Landrace piglets. These results suggested that thefi rst immunization could be administered to 35 days-old Sichuan-Tibet black piglets but to 25 days-old Landrace piglets.%为探索川藏黑猪和长白猪的猪瘟免疫方法,本研究采用猪瘟阻断ELISA对0、1、4、7、10、20、25、30、35日龄时川藏黑猪与长白猪仔猪的猪瘟母源抗体水平进行了检测.结果显示,川藏黑猪仔猪和长白猪仔猪出生后哺母乳前的猪瘟母源抗体均为0,哺母乳后d1,猪瘟母源抗体分别为>210和28.2,合格率分别为100%和87%.4日龄和7日龄时,川藏黑猪仔猪的猪瘟母源抗体仍为≥210,合格率100%;长白猪仔猪的猪瘟母源抗体为28.4和27.4,合格率100%和83%;随后川藏黑猪仔猪的猪瘟母源抗体呈下降趋势,35日龄达到保护临界值(24.0);长白猪仔猪的猪瘟母源抗体下降更迅速,25日龄时其母源抗体水平已达临界值(24.0).检测结果表明无论是母源抗体水

  12. African swine fever virus: current state and future perspectives in vaccine and antiviral research.

    Science.gov (United States)

    Zakaryan, Hovakim; Revilla, Yolanda

    2016-03-15

    African swine fever (ASF) is among the most significant of swine diseases for which no effective vaccines and antivirals are available. The disease, which is endemic in Africa, was introduced to Trans-Caucasian countries and the Russian Federation in 2007, where it remains prevalent today among domestic pigs and wild boars. Although some measures were implemented, ASF continues to pose a global risk for all countries, and thereby highlighting the importance of vaccine and antiviral research. In this review, an overview of research efforts toward the development of effective vaccines during the past decades is presented. As an alternative to vaccine development, the current state in antiviral research against ASFV is also presented. Finally, future perspectives in vaccine and antiviral research giving emphasis on some strategies that may allow researchers to develop effective countermeasures against ASF are discussed.

  13. Regulation of Apoptosis in African Swine Fever Virus–Infected Macrophages

    Directory of Open Access Journals (Sweden)

    Laslo Zsak

    2002-01-01

    Full Text Available A number of viruses have evolved antiapoptotic mechanisms to promote infected-cell survival, either to ensure efficient productive viral replication or to promote long-term survival of virus-infected cells. Recent studies identified critical African swine fever virus genes involved in the complex regulation of ASFV-host interactions. Here we review the present knowledge of the recently identified ASFV genes with special attention to those which affect viral virulence, host range, and pathogenesis by regulating viral-induced apoptotic mechanisms.

  14. 9 CFR 94.24 - Restrictions on the importation of pork, pork products, and swine from the APHIS-defined EU CSF...

    Science.gov (United States)

    2010-01-01

    ... NEWCASTLE DISEASE, AFRICAN SWINE FEVER, CLASSICAL SWINE FEVER, SWINE VESICULAR DISEASE, AND BOVINE... State who is authorized to issue the foreign meat inspection certificate required by § 327.4 of this... been met. 19 19 The certification required may be placed on the foreign meat inspection...

  15. Monitoring Experiment about Maternal Antibody and Immune Antibody of Grice Swine Fever%仔猪猪瘟母源抗体及免疫抗体监测实验研究

    Institute of Scientific and Technical Information of China (English)

    陈耀; 刘用玲

    2012-01-01

    由于猪瘟流行性差异,研究制订符合本地实际的猪瘟免疫程序是有效防控猪瘟的关键措施之一,而确定仔猪最佳首免日龄和免疫剂量是研究猪瘟免疫程序的两个重要内容。本文提出应用PPA(酶标葡萄球菌蛋白A)-ELISA法对达县某猪场进行了仔猪猪瘟母源抗体及免疫抗体监测实验研究,实验结果表明25日龄为最佳免疫日龄,1倍剂量为最佳免疫剂量。%Due to the difference of the Classical Swine Fever epidemic,the Classical Swine Fever immunization program according with local is one of key measures for effective prevention and control of the Classical Swine Fever. In the immunization program research,determination of the most fit age for first immunization and immune dosage are two important objects.This paper uses PPA(enzyme staphylococcal protein A) - ELISA method to make monitoring experimental research into maternal antibody and immune antibody of the Classical Swine Fever a pig farm of Daxian.The experiment shows that 25 days is the most fit immunization age,1 times dosage for the most fit immune dosage.

  16. 玉米赤霉烯酮毒素中毒继发猪瘟的诊断%Diagnosis of Zearalenone Poisoning Secondary for Swine Fever

    Institute of Scientific and Technical Information of China (English)

    杨建平; 王扬伟

    2012-01-01

    The pigs fed with high grade corn or moldy corn were checked for swine fever antibodies and disease respectively. The pigs fed moldy corn had low levels of antibodies against swine fever, and there was zearalenone poisoning secondary for swine fever. The pigs fed with high grade corn had qualified levels of antibodies against swine fever, and no swine disease occured.%作者对饲喂优质玉米和霉变玉米的猪分别进行猪瘟抗体和疫病检查,结果发现,饲喂霉变玉米的猪群猪瘟抗体水平低,且有玉米赤霉烯酮毒素中毒继发猪瘟的现象;饲喂优质玉米的猪群猪瘟抗体水平全部合格,猪群没有发生疫病.

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

    DEFF Research Database (Denmark)

    McKillan, John; McMenamy, Michael; Hjertner, Bernt;

    2010-01-01

    The design of a 5′ conjugated minor groove binder (MGB) probe real-time PCR assay is described for the rapid, sensitive and specific detection of African swine fever virus (ASFV) DNA. The assay is designed against the 9GL region and is capable of detecting 20 copies of a DNA standard. It does not...

  18. 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

    the subclinical stage and are fully infectious during the clinical stage. ASF virus (ASFV) infection through residues of dead animals in the slurries was also modeled in an exponentially fading-out pattern. Low and high transmission rates for ASFV were tested in the model. Robustness analysis was carried out......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...... in order to study the impact of uncertain parameters on model predictions. The results showed that the disease may fade out within the pig unit without a major outbreak. Furthermore, they showed that spread of ASFV is dependent on the infectiousness of subclinical animals and the residues of dead animals...

  19. 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

  20. First molecular assessment of the African swine fever virus status of Ornithodoros ticks from Swaziland

    Directory of Open Access Journals (Sweden)

    Carin I. Boshoff

    2014-02-01

    Full Text Available African swine fever (ASF is an economically significant haemorrhagic disease of domestic pigs. It is caused by the African swine fever virus (ASFV, a deoxyribonucleic acid (DNAarbovirus. Argasid ticks of the genus Ornithodoros, which are widely distributed throughout southern Africa, play a primary role in virus maintenance and spread within the endemic sylvatic cycle. The ASF status of Swaziland is unknown, but this land-locked country is surrounded by ASF-positive countries, has a burgeoning pig industry and sylvatic cycle hosts present within its borders. In this first assessment of ASF status, warthog burrows in seven nature reserves and game management areas in Swaziland were investigated for tick and virus presence. Tick infestation rates of between 33.3% – 88.8% were recovered for the four Ornithodoros-infested reserves. A total of 562 ticks were screened for virus genome presence using a duplex Polymerase Chain Reaction (PCR that targets the C-terminal end of the p72 gene of the ASFV and confirms DNA integrity through amplification of the 16S rRNA tick host gene. All samples were negative for virus genome presence and positive for the tick genome target. Nucleotide sequencing of the latter confirmed that Ornithodoros ticks from Swaziland are identical to those from the Kruger National Park in South Africa across the gene region characterised. Whilst this first evaluation of ASF presence in Swaziland indicates that the virus does not appear to be present in the key virus vector, the presence of sylvatic cycle hosts, together with the country’s proximity to ASF-affected countries calls for expanded investigations and regular monitoring of the ASF status of Swaziland.

  1. First molecular assessment of the African swine fever virus status of Ornithodoros ticks from Swaziland.

    Science.gov (United States)

    Boshoff, Carin I; Bastos, Armanda D S; Dube, Mzwandi M; Heath, Livio

    2014-12-03

    African swine fever (ASF) is an economically significant haemorrhagic disease of domestic pigs. It is caused by the African swine fever virus (ASFV), a deoxyribonucleic acid (DNA)arbovirus. Argasid ticks of the genus Ornithodoros, which are widely distributed throughout southern Africa, play a primary role in virus maintenance and spread within the endemic sylvatic cycle. The ASF status of Swaziland is unknown, but this land-locked country is surrounded by ASF-positive countries, has a burgeoning pig industry and sylvatic cycle hosts present within its borders. In this first assessment of ASF status, warthog burrows in seven nature reserves and game management areas in Swaziland were investigated for tick and virus presence. Tick infestation rates of between 33.3% - 88.8% were recovered for the four Ornithodoros-infested reserves. A total of 562 ticks were screened for virus genome presence using a duplex Polymerase Chain Reaction (PCR) that targets the C-terminal end of the p72 gene of the ASFV and confirms DNA integrity through amplification of the 16S rRNA tick host gene. All samples were negative for virus genome presence and positive for the tick genome target. Nucleotide sequencing of the latter confirmed that Ornithodoros ticks from Swaziland are identical to those from the Kruger National Park in South Africa across the gene region characterised. Whilst this first evaluation of ASF presence in Swaziland indicates that the virus does not appear to be present in the key virus vector, the presence of sylvatic cycle hosts, together with the country's proximity to ASF-affected countries calls for expanded investigations and regular monitoring of the ASF status of Swaziland.

  2. Evaluation of hemostaseological status of pigs experimentally infected with African swine fever virus.

    Science.gov (United States)

    Zakaryan, Hovakim; Karalova, Elena; Voskanyan, Henrik; Ter-Pogossyan, Zarine; Nersisyan, Narek; Hakobyan, Astghik; Saroyan, David; Karalyan, Zaven

    2014-11-01

    African swine fever is a highly contagious hemorrhagic disease of pigs caused by African swine fever virus (ASFV). Hemorrhages are the most frequently reported lesions in acute and subacute forms of ASF. Hemorrhagic lesions are accompanied by impaired hemostasis, which includes thrombocytopenia and changes in the coagulation system. In the present study, experimental infection was conducted to elucidate whether a highly virulent ASFV genotype II circulating in the Trans-Caucasus and Eastern Europe affects the hemostasis of infected pigs. Platelet count changes and platelet size, as well as coagulation parameters were evaluated upon experimental infection. In contrast to other ASFV strains, ASFV genotype II showed a significant decrease in the number of platelets from 3rd dpi onwards. Furthermore, a decrease in platelet size was observed throughout the entire period of experiment. A significant increase in the number of platelet aggregates was observed from the beginning of infection. Unlike other ASFV strains, ASFV genotype II induced a slight shortening of an activated partial thromboplastin time (aPTT) throughout the experiment. Thrombin time (TT) was prolonged from day 5 onwards, whereas no changes in prothrombin time (PT) were found upon infection. The level of d-dimers was permanently higher than in control with a peak on day 3 post-infection. ASFV induced a significant decrease in the level of fibrinogen from day 5 till the end of experiment. Thus, it can be concluded that ASFV genotype II isolated in Armenia affects the hemostasis of infected pigs and causes changes that differ from that of other ASFV strains described previously.

  3. BacMam immunization partially protects pigs against sublethal challenge with African swine fever virus.

    Science.gov (United States)

    Argilaguet, Jordi M; Pérez-Martín, Eva; López, Sergio; Goethe, Martin; Escribano, J M; Giesow, Katrin; Keil, Günther M; Rodríguez, Fernando

    2013-04-01

    Lack of vaccines and efficient control measures complicate the control and eradication of African swine fever (ASF). Limitations of conventional inactivated and attenuated virus-based vaccines against African swine fever virus (ASFV) highlight the need to use new technologies to develop efficient and safe vaccines against this virus. With this aim in mind, in this study we have constructed BacMam-sHAPQ, a baculovirus based vector for gene transfer into mammalian cells, expressing a fusion protein comprising three in tandem ASFV antigens: p54, p30 and the extracellular domain of the viral hemagglutinin (secretory hemagglutinin, sHA), under the control of the human cytomegalovirus immediate early promoter (CMVie). Confirming its correct in vitro expression, BacMam-sHAPQ induced specific T-cell responses directly after in vivo immunization. Conversely, no specific antibody responses were detectable prior to ASFV challenge. The protective potential of this recombinant vaccine candidate was tested by a homologous sublethal challenge with ASFV following immunization. Four out of six immunized pigs remained viremia-free after ASFV infection, while the other two pigs showed similar viremic titres to control animals. The protection afforded correlated with the presence of a large number of virus-specific IFNγ-secreting T-cells in blood at 17 days post-infection. In contrast, the specific antibody levels observed after ASFV challenge in sera from BacMam-sHAPQ immunized pigs were indistinguishable from those found in control pigs. These results highlight the importance of the cellular responses in protection against ASFV and point towards BacMam vectors as potential tools for future vaccine development.

  4. 9 CFR 94.12 - Pork and pork products from regions where swine vesicular disease exists.

    Science.gov (United States)

    2010-01-01

    ... FEVER, CLASSICAL SWINE FEVER, SWINE VESICULAR DISEASE, AND BOVINE SPONGIFORM ENCEPHALOPATHY: PROHIBITED... products shall be consigned directly from the port of entry in the United States to a meat processing establishment operating under Federal meat inspection and approved by the Administrator, 12 for heating to...

  5. 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...

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

    Science.gov (United States)

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

    2016-01-01

    African swine fever (ASF) is a lethal hemorrhagic disease of swine caused by a double-stranded DNA virus, ASF virus (ASFV). There is no vaccine to prevent the disease and current control measures are limited to culling and restricting animal movement. Swine infected with attenuated strains are protected against challenge with a homologous virulent virus, but there is limited knowledge of the host immune mechanisms generating that protection. Swine infected with Pretoriuskop/96/4 (Pret4) virus develop a fatal severe disease, while a derivative strain lacking virulence-associated gene 9GL (Pret4Δ9GL virus) is completely attenuated. Swine infected with Pret4Δ9GL virus and challenged with the virulent parental virus at 7, 10, 14, 21, and 28 days post infection (dpi) showed a progressive acquisition of protection (from 40% at 7 dpi to 80% at 21 and 28 dpi). This animal model was used to associate the presence of host immune response (ASFV-specific antibody and interferon (IFN)-γ responses, or specific cytokine profiles) and protection against challenge. With the exception of ASFV-specific antibodies in survivors challenged at 21 and 28 dpi, no association between the parameters assessed and protection could be established. These results, encompassing data from 65 immunized swine, underscore the complexity of the system under study, suggesting that protection relies on the concurrence of different host immune mechanisms. PMID:27782090

  7. EFFECT OF DIFFERENT VACCINATION PROTOCOLS ON ANTIBODY LEVELS OF HIGHLY PATHOGENIC PORCINE REPRODUCTIVE AND RESPIRATORY SYNDROME, CLASSICAL SWINE FEVER AND FOOT AND MOUTH DISEASE VACCINES IN PIGLETS%不同免疫方式对仔猪免疫高致病性猪繁殖与呼吸综合征、猪瘟、猪口蹄疫三种疫苗抗体水平的影响

    Institute of Scientific and Technical Information of China (English)

    胡杰; 张步娴; 屈素洁; 莫胜兰; 粟艳琼; 陆文俊; 施开创; 李军

    2014-01-01

    Different vaccination protocols were taken to vaccinate thirty-eight 36-38-day-old healthy piglets with highly pathogenic porcine reproductive and respiratory syndrome (HP-PRRS), classical swine fever (CSF) and foot and mouth disease (FMD) vaccines, respectively. The antibody levels of CSFV, FMDV and PRRSV were tested on day 0, 15, 30, 45, 60 and 90 post vaccination. The highest antibody levels were detected when CSF and FMD vaccines were used first followed by HP-PRRS vaccine 14 days later. The second choice was that CSF and HP-PRRS vaccines were mixed in one shot on one side of piglets and at the same time FMD vaccine was used on other side. The lowest antibody levels were detected when HP-PRRS, FMD and CSF vaccines were injected at the same time at three separate shots.%采用不同的免疫方式,对38头36~38日龄健康仔猪进行高致病性猪繁殖与呼吸综合征、猪瘟、猪口蹄疫3种疫苗进行免疫,分别于免疫前(0 d)和免疫后15、30、45、60、90 d采血进行这3种疫病抗体检测。结果发现效果最好的方法是先免疫猪瘟和口蹄疫疫苗14 d后再免疫高致病性猪繁殖与呼吸综合征疫苗;其次是猪瘟疫苗和高致病性猪繁殖与呼吸综合征疫苗分别释稀后混合为1针,口蹄疫疫苗另作1针同时分点注射;免疫效果最差的是高致病性猪繁殖与呼吸综合征、猪瘟、猪口蹄疫3种疫苗同时分3点注射。

  8. 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

  9. 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。

  10. 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

  11. 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

  12. Dynamin- and Clathrin-Dependent Endocytosis in African Swine Fever Virus Entry▿

    Science.gov (United States)

    Hernaez, Bruno; Alonso, Covadonga

    2010-01-01

    African swine fever virus (ASFV) is a large DNA virus that enters host cells after receptor-mediated endocytosis and depends on acidic cellular compartments for productive infection. The exact cellular mechanism, however, is largely unknown. In order to dissect ASFV entry, we have analyzed the major endocytic routes using specific inhibitors and dominant negative mutants and analyzed the consequences for ASFV entry into host cells. Our results indicate that ASFV entry into host cells takes place by clathrin-mediated endocytosis which requires dynamin GTPase activity. Also, the clathrin-coated pit component Eps15 was identified as a relevant cellular factor during infection. The presence of cholesterol in cellular membranes, but not lipid rafts or caveolae, was found to be essential for a productive ASFV infection. In contrast, inhibitors of the Na+/H+ ion channels and actin polymerization inhibition did not significantly modify ASFV infection, suggesting that macropinocytosis does not represent the main entry route for ASFV. These results suggest a dynamin-dependent and clathrin-mediated endocytic pathway of ASFV entry for the cell types and viral strains analyzed. PMID:19939916

  13. Transmission routes of African swine fever virus to domestic pigs: current knowledge and future research directions.

    Science.gov (United States)

    Guinat, Claire; Gogin, Andrey; Blome, Sandra; Keil, Guenther; Pollin, Reiko; Pfeiffer, Dirk U; Dixon, Linda

    2016-03-12

    African swine fever (ASF) is a major threat to the pig industry in Europe. Since 2007, ASF outbreaks have been ongoing in the Caucasus, Eastern Europe and the Baltic countries, causing severe economic losses for many pig farmers and pork producers. In addition, the number of ASF cases in wild boar populations has dramatically increased over the past few years. Evidence supports direct contact with infectious domestic pigs and wild boars, and consumption of contaminated feed, as the main transmission routes of ASF virus (ASFV) to domestic pigs. However, significant knowledge gaps highlight the urgent need for research to investigate the dynamics of indirect transmission via the environment, the minimal infective doses for contaminated feed ingestion, the probability of effective contacts between infectious wild boars and domestic pigs, the potential for recovered animals to become carriers and a reservoir for transmission, the potential virus persistence within wild boar populations and the influence of human behaviour for the spread of ASFV. This will provide an improved scientific basis to optimise current interventions and develop new tools and strategies to reduce the risk of ASFV transmission to domestic pigs.

  14. Evaluation of the risk factors contributing to the African Swine Fever occurrence in Sardinia, Italy

    Directory of Open Access Journals (Sweden)

    Beatriz eMartínez-López

    2015-04-01

    Full Text Available This study assesses the relation between hypothesized risk factors and African swine fever virus (ASFV distribution in Sardinia (Italy after the beginning of the eradication program in 1993, using a Bayesian multivariable logistic regression mixed model. Results indicate that the probability of ASFV occurrence in Sardinia was associated to particular socio-cultural, productive and economical factors found in the region, particularly to large number of confined (i.e. closed farms (most of them backyard, high roads density, high mean altitude, large number of open fattening farms, and large number of pigs per commune. Conversely, large proportion of open farms with at least one census and large proportion of open farms per commune, were found to be protective factors for ASFV. Results suggest that basic preventive and control strategies, such as yearly census or registration of the pigs per farm and better control of the public lands where pigs are usually raised, together with endanced effords of outreach and communication with pig producers should help in the success of the eradication program for ASF in the Island. Methods and results presented here will inform decision making to better control and eradicate ASF in Sardinia and in all those areas with similar management and epidemiological conditions.

  15. 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.

  16. Subclinical Swine Fever and Antibody Titer Analyze on Piglets%仔猪散发亚临床猪瘟及其抗体效价分析

    Institute of Scientific and Technical Information of China (English)

    吴凌; 白云龙; 冉旭华; 夏成; 邵红

    2014-01-01

    黑龙江某养猪户仔猪零星发病死亡,经PCR诊断为亚临床猪瘟。采集了60头母猪血,采用间接ELISA试剂盒检测60头母猪猪瘟免疫抗体水平。结果表明,该户母猪猪瘟免疫抗体水平较低,免疫抗体合格率仅为3.3%。因此,母猪免疫失败是导致仔猪散发猪瘟的主要原因。%Some piglets died in a pig farm sporadically, and diagnosed as subclinical swine fe-ver by a PCR test. Blood samples were collected from 60 sows for detecting immune antibody levels of swine fever. Results showed that swine fever antibody levels were low after vaccination in sow, the qualified rate of immune antibody is only 3.3%. Therefore, immune failure to swine fever in sows was the main reason caused swine fever occur sporadically in these piglets herd.

  17. 2010~2013年田东县猪瘟免疫效果调查分析%2010~2013 Tiandong county investigation of swine fever immune

    Institute of Scientific and Technical Information of China (English)

    黄宝学; 蒙振亩; 韦显凯

    2015-01-01

    利用正向间接血凝试验采集田东县2010~2013年种公母猪、保育仔猪和生长育肥猪经过猪瘟疫苗一免、二免后28d的血清和未免疫的哺乳仔猪血清共2606份进行猪瘟免疫抗体检测,观察抗体水平变化情况,并对各生长阶段猪群的免疫效果进行调查分析。结果表明:2010~2013年猪群猪瘟抗体合格率分别为73.44%、76.08%、80.87%、86.22%,平均合格率为79.24%,总体呈逐年上升趋势;种公母猪平均合格率最高,达91.55%,其次为生长育肥猪和哺乳仔猪,平均合格率分别为84.19%、72.25%,保育仔猪最低,平均合格率为65.92%;一免、二免的平均抗体合格率分别为51.24%、82.72%,二免显著高于一免。结果表明:各个猪场应对保育仔猪有针对性的免疫并及时淘汰经二次免疫以上抗体不合格的种公母猪,推行二次强化免疫工作,以提高猪群猪瘟抗体合格率。%Use indirect hemagglutination test collection Tiandong 2010~2013 stud sows, nursery pigs and finishing pigs in a classical swine fever vaccine through free, serum-free after two and unvaccinated piglets serum total of 2606 copies were 28d Classical swine fever immunization antibody detection, antibody levels observed changes, and the effect of different growth stages of herd immunity investigation and analysis. The results show that:In 2010~2013 herd swine fever antibodies qualification rates were 73.44%, 76.08%, 80.87%, 86.22%, the average pass rate of 79.24%, the overall upward trend year by year;stud sow average pass rate was the highest up 91.55 percent, followed by growing and finishing pigs and piglets, the average pass rate of 84.19 percent, respectively, 72.25%, the lowest nursery pigs, the average pass rate of 65.92%;a free, two free mean antibody pass rate 51.24%, respectively, 82.72%, significantly higher than the one two free free. The results showed that:respond each nursery pigs farms targeted immune and

  18. 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

  19. Spatio-temporal dynamics of African swine fever outbreaks in Nigeria, 2002-2007.

    Science.gov (United States)

    Owolodun, O A; Yakubu, B; Antiabong, J F; Ogedengbe, M E; Luka, P D; John Audu, B; Ekong, P S; Shamaki, D

    2010-10-01

    African swine fever (ASF) was first introduced into Nigeria through Lagos state in 1997. The disease rapidly spread to Ogun state in 1998 and extended to the Niger Delta (Delta, Rivers and Akwa Ibom states) in the same year. In 1998, Kaduna, Plateau and Benue states all north of the country experienced ASF for the first time. Poor farm biosecurity, bad abattoir practices and extensive/free range pig farming systems led to extensive spread of the diseases to about 16 Nigerian states excluding the far northwest and north east. A total of 1036 field samples collected over a 6-year period covering 19 Nigerian states were analysed during the period under review; 805 samples were PCR positive and 231 negative. Positive samples were detected in all three surveillance phases and from all agroecological zones across the country. For the first time since its incursion, ASF was identified in some states; Bauchi, Adamawa Taraba and Gombe with chances of control very slim and further spread of the virus northward envisaged. Outbreaks of the disease are now a perennial problem with an increasing disease burden in areas where high numbers of pigs are produced in the country. The National Veterinary Research Institute (NVRI), Vom, since 2002 investigated ASF based on tissue submissions and reports made by individuals, private & commercial farms and agricultural bodies. We present an analysis of geographical and temporal distribution of ASF in the country from 2002 to 2007 and a review of historic outbreaks since the first incursion. Risk factors and prospects for control are discussed.

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

    Directory of Open Access Journals (Sweden)

    Mike B Barongo

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

  1. 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.

  2. Molecular characterization of African swine fever virus from domestic pigs in northern Tanzania during an outbreak in 2013.

    Science.gov (United States)

    Misinzo, Gerald; Kwavi, David E; Sikombe, Christopher D; Makange, Mariam; Peter, Emma; Muhairwa, Amandus P; Madege, Michael J

    2014-10-01

    African swine fever (ASF) is an acute, highly contagious and deadly viral hemorrhagic fever of domestic pigs caused by African swine fever virus (ASFV), a double-stranded DNA virus of the family Asfarviridae. In this study, molecular diagnosis and characterization of outbreak ASFV in northern Tanzania, was performed on spleen, lymph node, kidney, and heart samples collected in June and July 2013 from domestic pigs that died during a hemorrhagic disease outbreak. Confirmatory diagnosis of ASF was performed using polymerase chain reaction (PCR) by partial amplification of B646L gene of ASFV encoding the major capsid protein p72 using PPA1/PPA2 primers. PCR using PPA1/PPA2 primers produced an expected PCR product size, confirming ASF outbreak in northern Tanzania. In addition, nucleotide amplification and sequencing, and phylogenetic reconstruction of the variable 3'-end of the B646L gene and complete E183L gene encoding the inner envelope transmembrane protein p54 showed that the 2013 outbreak ASFV from northern Tanzania were 100 % identical and clustered into ASFV B646L (p72) and E183L (p54) genotype X. Furthermore, the tetrameric amino acid repeats within the central variable region (CVR) of the B602L gene coding for the J9L protein had the signature BNBA(BN)5NA with a single novel tetramer NVDI (repeat code N). The results of the present study confirm an ASF outbreak in northern Tanzania in the year 2013 and show that the present outbreak ASFV is closely related to other ASFV from ticks, warthogs, and domestic pigs previously reported from Tanzania.

  3. 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...

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

    NARCIS (Netherlands)

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

    2009-01-01

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

  5. 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.,...

  6. 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

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

    Science.gov (United States)

    2012-01-01

    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 health facilities. The

  8. Effect of O. porcinus Tick Salivary Gland Extract on the African Swine Fever Virus Infection in Domestic Pig

    Science.gov (United States)

    Bernard, Jennifer; Hutet, Evelyne; Paboeuf, Frédéric; Randriamparany, Tantely; Holzmuller, Philippe; Lancelot, Renaud; Rodrigues, Valérie; Vial, Laurence; Le Potier, Marie-Frédérique

    2016-01-01

    African swine fever is a haemorrhagic disease in pig production that can have disastrous financial consequences for farming. No vaccines are currently available and animal slaughtering or area zoning to restrict risk-related movements are the only effective measures to prevent the spread of the disease. Ornithodoros soft ticks are known to transmit the African swine fever virus (ASFV) to pigs in farms, following the natural epidemiologic cycle of the virus. Tick saliva has been shown to modulate the host physiological and immunological responses during feeding on skin, thus affecting viral infection. To better understand the interaction between soft tick, ASFV and pig at the bite location and the possible influence of tick saliva on pig infection by ASFV, salivary gland extract (SGE) of Ornithodoros porcinus, co-inoculated or not with ASFV, was used for intradermal auricular inoculation. Our results showed that, after the virus triggered the disease, pigs inoculated with virus and SGE presented greater hyperthermia than pigs inoculated with virus alone. The density of Langerhans cells was modulated at the tick bite or inoculation site, either through recruitment by ASFV or inhibition by SGE. Additionally, SGE and virus induced macrophage recruitment each. This effect was enhanced when they were co-inoculated. Finally, the co-inoculation of SGE and virus delayed the early local spread of virus to the first lymph node on the inoculation side. This study has shown that the effect of SGE was powerful enough to be quantified in pig both on the systemic and local immune response. We believe this model should be developed with infected tick and could improve knowledge of both tick vector competence and tick saliva immunomodulation. PMID:26828597

  9. 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.

  10. 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.

  11. Dynamics of African swine fever virus shedding and excretion in domestic pigs infected by intramuscular inoculation and contact transmission.

    Science.gov (United States)

    Guinat, Claire; Reis, Ana Luisa; Netherton, Christopher L; Goatley, Lynnette; Pfeiffer, Dirk U; Dixon, Linda

    2014-09-26

    African swine fever virus (ASFV) is a highly virulent swine pathogen that has spread across Eastern Europe since 2007 and for which there is no effective vaccine or treatment available. The dynamics of shedding and excretion is not well known for this currently circulating ASFV strain. Therefore, susceptible pigs were exposed to pigs intramuscularly infected with the Georgia 2007/1 ASFV strain to measure those dynamics through within- and between-pen transmission scenarios. Blood, oral, nasal and rectal fluid samples were tested for the presence of ASFV by virus titration (VT) and quantitative real-time polymerase chain reaction (qPCR). Serum was tested for the presence of ASFV-specific antibodies. Both intramuscular inoculation and contact transmission resulted in development of acute disease in all pigs although the experiments indicated that the pathogenesis of the disease might be different, depending on the route of infection. Infectious ASFV was first isolated in blood among the inoculated pigs by day 3, and then chronologically among the direct and indirect contact pigs, by day 10 and 13, respectively. Close to the onset of clinical signs, higher ASFV titres were found in blood compared with nasal and rectal fluid samples among all pigs. No infectious ASFV was isolated in oral fluid samples although ASFV genome copies were detected. Only one animal developed antibodies starting after 12 days post-inoculation. The results provide quantitative data on shedding and excretion of the Georgia 2007/1 ASFV strain among domestic pigs and suggest a limited potential of this isolate to cause persistent infection.

  12. 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

    . In this study, we analyzed NGS data of virus rescued from a CSFV C-strain vaccine strain cDNA clone. The virus analyzed was obtained from a 4th and a 12th passage of rescued virus in SFT cell culture, which had shown a difference in growth kinetics between the passages, and NGS analysis was chosen in order...... to look for molecular differences. Identical RT-PCR products were run on both GS FLX and an Iontorrent PGM platform for comparison. The NGS data was compared by quality and the percentage mapped reads. Results showed good quality of reads for both platforms and a close to 100% of the reads mapped...

  13. 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.;

    separately. Methods Experiment I: 12 pigs, 6 weeks of age, originating from 2 litters of the institute’s own SPF herd. The pigs were randomly divided into two groups each of 6 pigs – a control group and a virus-inoculated group. Experiment II: 12 pigs, 12 weeks of age, originating from the institute’s own...... SPF herd. The 6 control pigs from experiment I were applied as controls in experiment II, too. The virus-inoculated group, six pigs were littermates to the pigs from experiment I. Experiment III: 10 pigs, 6 weeks of age, of different genetic background than the pigs in experiment I and II, originated...... from the University of Copenhagen, Faculty of Life Sciences. The litter comprised normal pigs as well as pigs of a new phenotype, initially characterized by juvenile hairlessness and thin skin, which was discovered in a Danish pig herd. All 10 pigs were virus inoculated. The experimental set...

  14. 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

    proteins considered non-essential for RNA replication were constructed and these deletions were replaced with an in-frame insertion of the Renilla luciferase (Rluc) sequence. RNA transcripts from these replicons should be translated as a single functional open reading frame. Full-genome cDNAs (~10-12,3 kb......) were amplified from the BACs using a stable long-PCR method and in vitro transcripts were assayed in permissive cells. The CSFV-Rluc replicons were evaluated for their ability to replicate using immunofluorescence staining (-NS3 and -E2), and the Renilla luciferase assay. We conclude that Rluc...

  15. 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

    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...

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

    NARCIS (Netherlands)

    Bergevoet, R.H.M.; Asseldonk, van M.A.P.M.

    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 w

  17. 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...

  18. Rationale for classical biological control of cattle fever ticks and proposed methods for field collection of natural enemies

    Science.gov (United States)

    Classical biological control using specialist parasitoids, predators and/or nematodes from the native ranges of cattle fever ticks Rhipicephalus microplus and Rhipicephalus annulatus could complement existing control strategies for this livestock pest in the transboundary region between Mexico and T...

  19. An investigation into natural resistance to African swine fever in domestic pigs from an endemic area in southern Africa.

    Science.gov (United States)

    Penrith, M L; Thomson, G R; Bastos, A D S; Phiri, O C; Lubisi, B A; Du Plessis, E C; Macome, F; Pinto, F; Botha, B; Esterhuysen, J

    2004-12-01

    A population of domestic pigs in northern Mozambique with increased resistance to the pathogenic effects of African swine fever (ASF) virus was identified by the high prevalence of circulating antibodies to ASF virus. An attempt was made to establish whether the resistance in this population was heritable. Some of these pigs were acquired and transported to a quarantine facility and allowed to breed naturally. Offspring of the resistant pigs were transferred to a high security facility where they were challenged with two ASF viruses, one of which was isolated from one of the Mozambican pigs and the other a genetically closely-related virus from Madagascar. All but one of the 105 offspring challenged developed acute ASF and died. It therefore appears that the resistance demonstrated by these pigs is not inherited by their offspring, or could not be expressed under the conditions of the experiment. The question remains therefore as to the mechanism whereby pigs in the population from which the experimental pigs were derived co-existed with virulent ASF viruses.

  20. 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.

  1. 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

  2. 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

  3. 9 CFR 98.15 - Health requirements.

    Science.gov (United States)

    2010-01-01

    ..., classical swine fever, pseudorabies, rinderpest, swine vesicular disease, or vesicular stomatitis. (2... stomatitis; or (B) Swine: African swine fever, classical swine fever, pseudorabies, rinderpest, swine... fever, brucellosis, foot-and-mouth disease, classical swine fever, pseudorabies, rinderpest,...

  4. 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 <15 pigs) and apply little to no biosecurity measures. Additionally, illegally raised pigs are still bred in free-ranging systems in certain isolated parts of the island, despite strict regulations. The illegal raising of pigs, along with other high-risk management 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.

  5. African swine fever in Uganda: qualitative evaluation of three surveillance methods with implications for other resource-poor settings

    Directory of Open Access Journals (Sweden)

    Erika eChenais

    2015-10-01

    Full Text Available Animal diseases impact negatively on households and on national economies. In low-income countries this pertains especially to socio-economic effects on household level. To control animal diseases and mitigate their impact, it is necessary to understand the epidemiology of the disease in its local context. Such understanding, gained through disease surveillance, is often lacking in resource-poor settings. Alternative surveillance methods have been developed to overcome some of the hurdles obstructing surveillance. The objective of this study was to evaluate and qualitatively compare three methods for surveillance of acute infectious diseases using African swine fever (ASF in northern Uganda as an example. Report-driven outbreak investigations, participatory rural appraisals (PRA, and a household survey using a smartphone application were evaluated. All three methods had good disease-detecting capacity, each of them detected many more outbreaks compared to those reported to the World Organization for Animal Health (OIE during the same time period. Apparent mortality rates were similar for the three methods although highest for the report-driven outbreak investigations, followed by the PRAs, and then the household survey. The three methods have different characteristics and the method of choice will depend on the surveillance objective. The optimal situation might be achieved by a combination of the methods: outbreak detection via smartphone-based real-time surveillance, outbreak investigation for collection of biological samples, and a PRA for a better understanding of the epidemiology of the specific outbreak. All three methods require initial investments and continuous efforts. The sustainability of the surveillance system should therefore be carefully evaluated before making such investments.

  6. 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

  7. Experimental Transmission of African Swine Fever (ASF) Low Virulent Isolate NH/P68 by Surviving Pigs.

    Science.gov (United States)

    Gallardo, C; Soler, A; Nieto, R; Sánchez, M A; Martins, C; Pelayo, V; Carrascosa, A; Revilla, Y; Simón, A; Briones, V; Sánchez-Vizcaíno, J M; Arias, M

    2015-12-01

    African swine fever (ASF) has persisted in Eastern Europe since 2007, and two endemic zones have been identified in the central and southern parts of the Russian Federation. Moderate- to low-virulent ASF virus isolates are known to circulate in endemic ASF-affected regions. To improve our knowledge of virus transmission in animals recovered from ASF virus infection, an experimental in vivo study was carried out. Four domestic pigs were inoculated with the NH/P68 ASF virus, previously characterized to develop a chronic form of ASF. Two additional in-contact pigs were introduced at 72 days post-inoculation (dpi) in the same box for virus exposure. The inoculated pigs developed a mild form of the disease, and the virus was isolated from tissues in the inoculated pigs up to 99 dpi (pigs were euthanized at 36, 65, 99 and 134 dpi). In-contact pigs showed mild or no clinical signs, but did become seropositive, and a transient viraemia was detected at 28 days post-exposure (dpe), thereby confirming late virus transmission from the inoculated pigs. Virus transmission to in-contact pigs occurred at four weeks post-exposure, over three months after the primary infection. These results highlight the potential role of survivor pigs in disease maintenance and dissemination in areas where moderate- to low-virulent viruses may be circulating undetected. This study will help design better and more effective control programmes to fight against this disease.

  8. 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.

  9. 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

  10. 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...

  11. 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.

  12. Co-circulation of pandemic 2009 H1N1, classical swine H1N1 and avian-like swine H1N1 influenza viruses in pigs in China.

    Science.gov (United States)

    Chen, Yan; Zhang, Jian; Qiao, Chuanling; Yang, Huanliang; Zhang, Ying; Xin, Xiaoguang; Chen, Hualan

    2013-01-01

    The pandemic A/H1N1 influenza viruses emerged in both Mexico and the United States in March 2009, and were transmitted efficiently in the human population. They were transmitted occasionally from humans to other mammals including pigs, dogs and cats. In this study, we report the isolation and genetic analysis of novel viruses in pigs in China. These viruses were related phylogenetically to the pandemic 2009 H1N1 influenza viruses isolated from humans and pigs, which indicates that the pandemic virus is currently circulating in swine populations, and this hypothesis was further supported by serological surveillance of pig sera collected within the same period. Furthermore, we isolated another two H1N1 viruses belonging to the lineages of classical swine H1N1 virus and avian-like swine H1N1 virus, respectively. Multiple genetic lineages of H1N1 viruses are co-circulating in the swine population, which highlights the importance of intensive surveillance for swine influenza in China.

  13. 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

  14. Vaccination with viral protein-mimicking peptides postpones mortality in domestic pigs infected by African swine fever virus.

    Science.gov (United States)

    Ivanov, Vadim; Efremov, Evgeniy E; Novikov, Boris V; Balyshev, Vladimir M; Tsibanov, Sodnom Zh; Kalinovsky, Tatiana; Kolbasov, Denis V; Niedzwiecki, Aleksandra; Rath, Matthias

    2011-01-01

    Periodic outbreaks of African swine fever virus (ASFV) infection around the world threaten local populations of domestic pigs with lethal disease and provide grounds for pandemic spread. Effective vaccination may bring this threat under control. We investigated the effectiveness of select peptides mimicking viral proteins in establishing a protective immune response. Forty-six synthetic peptides based on the analysis of the complete nucleotide sequence of ASFV were tested for immunogenicity in mice. The 17 best immune response-inducing peptide candidates were selected for further investigation. Twenty-four domestic pigs, 3-4 months old and weighing 20-25 kg, were divided into six groups (n = 4) and immunized by subcutaneous injection using a standard three-round injection protocol with one of four peptide combinations prepared from the 17 peptides (Groups 1-4) or with carrier only (Group 5). Group 6, the control, was not vaccinated. Animal body temperature and behavior were monitored during and post immunization for health assessment. Two weeks after the last round of immunizations, the pigs were infected with live ASFV (Espania 70) at 6.0 Ig GAE50/cm3, and the survival rate was monitored. Blood samples were collected for analysis the day before infection and on days 3, 7 and 10 post-infection, or from deceased animals. The serum titers of specific immunoglobulins against synthetic peptides and whole inactivated ASFV were determined by enzyme immunoassay before and after infection. The presence of viral DNA in blood serum samples was determined by polymerase chain reaction. Viral infection activity in blood sera was determined by heme absorption in cultured porcine bone marrow and porcine leukocyte cells. Repeating the injection of synthetic peptides in both the mice and pigs produced an immune response specific to individual peptides, which differed widely in the intensity scale. Specific anti-whole virus immunoglobulin binding activity in the swine serum samples

  15. 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

  16. Analysis of the non classical class I genes of the MHC in swine

    OpenAIRE

    Rui, Hu

    2011-01-01

    In pig, very little information is available on the three non classical MHC class I genes SLA-6, -7 and -8 (SLA-Ib genes). Our aim was to increase knowledge on SLA-Ib genes by studying their polymorphism, transcription and protein expression. Full length transcripts were characterized from thymus and brain of MeLiM pigs resulting in the annotation of 8 exons for SLA-7 and -8 and 7 exons for SLA-6. The three full length cDNAs encode molecules with a predicted folding consistent with peptide pr...

  17. Co-infection of classic swine H1N1 influenza virus in pigs persistently infected with porcine rubulavirus.

    Science.gov (United States)

    Rivera-Benitez, José Francisco; De la Luz-Armendáriz, Jazmín; Saavedra-Montañez, Manuel; Jasso-Escutia, Miguel Ángel; Sánchez-Betancourt, Ivan; Pérez-Torres, Armando; Reyes-Leyva, Julio; Hernández, Jesús; Martínez-Lara, Atalo; Ramírez-Mendoza, Humberto

    2016-02-29

    Porcine rubulavirus (PorPV) and swine influenza virus infection causes respiratory disease in pigs. PorPV persistent infection could facilitate the establishment of secondary infections. The aim of this study was to analyse the pathogenicity of classic swine H1N1 influenza virus (swH1N1) in growing pigs persistently infected with porcine rubulavirus. Conventional six-week-old pigs were intranasally inoculated with PorPV, swH1N1, or PorPV/swH1N1. A mock-infected group was included. The co-infection with swH1N1 was at 44 days post-infection (DPI), right after clinical signs of PorPV infection had stopped. The pigs of the co-infection group presented an increase of clinical signs compared to the simple infection groups. In all infected groups, the most recurrent lung lesion was hyperplasia of the bronchiolar-associated lymphoid tissue and interstitial pneumonia. By means of immunohistochemical evaluation it was possible to demonstrate the presence of the two viral agents infecting simultaneously the bronchiolar epithelium. Viral excretion of PorPV in nasal and oral fluid was recorded at 28 and 52 DPI, respectively. PorPV persisted in several samples from respiratory tissues (RT), secondary lymphoid organs (SLO), and bronchoalveolar lavage fluid (BALF). For swH1N1, the viral excretion in nasal fluids was significantly higher in single-infected swH1N1 pigs than in the co-infected group. However, the co-infection group exhibited an increase in the presence of swH1N1 in RT, SLO, and BALF at two days after co-infection. In conclusion, the results obtained confirm an increase in the clinical signs of infection, and PorPV was observed to impact the spread of swH1N1 in analysed tissues in the early stage of co-infection, although viral shedding was not enhanced. In the present study, the interaction of swH1N1 infection is demonstrated in pigs persistently infected with PorPV.

  18. 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

  19. Detection of African Swine Fever Virus Antibodies in Serum and Oral Fluid Specimens Using a Recombinant Protein 30 (p30) Dual Matrix Indirect ELISA.

    Science.gov (United States)

    Giménez-Lirola, Luis G; Mur, Lina; Rivera, Belen; Mogler, Mark; Sun, Yaxuan; Lizano, Sergio; Goodell, Christa; Harris, D L Hank; Rowland, Raymond R R; Gallardo, Carmina; Sánchez-Vizcaíno, José Manuel; Zimmerman, Jeff

    2016-01-01

    In the absence of effective vaccine(s), control of African swine fever caused by African swine fever virus (ASFV) must be based on early, efficient, cost-effective detection and strict control and elimination strategies. For this purpose, we developed an indirect ELISA capable of detecting ASFV antibodies in either serum or oral fluid specimens. The recombinant protein used in the ELISA was selected by comparing the early serum antibody response of ASFV-infected pigs (NHV-p68 isolate) to three major recombinant polypeptides (p30, p54, p72) using a multiplex fluorescent microbead-based immunoassay (FMIA). Non-hazardous (non-infectious) antibody-positive serum for use as plate positive controls and for the calculation of sample-to-positive (S:P) ratios was produced by inoculating pigs with a replicon particle (RP) vaccine expressing the ASFV p30 gene. The optimized ELISA detected anti-p30 antibodies in serum and/or oral fluid samples from pigs inoculated with ASFV under experimental conditions beginning 8 to 12 days post inoculation. Tests on serum (n = 200) and oral fluid (n = 200) field samples from an ASFV-free population demonstrated that the assay was highly diagnostically specific. The convenience and diagnostic utility of oral fluid sampling combined with the flexibility to test either serum or oral fluid on the same platform suggests that this assay will be highly useful under the conditions for which OIE recommends ASFV antibody surveillance, i.e., in ASFV-endemic areas and for the detection of infections with ASFV isolates of low virulence. PMID:27611939

  20. 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.

  1. 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

  2. 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

  3. Transcription variants of SLA-7, a swine non classical MHC class I gene.

    Science.gov (United States)

    Hu, Rui; Lemonnier, Gaëtan; Bourneuf, Emmanuelle; Vincent-Naulleau, Silvia; Rogel-Gaillard, Claire

    2011-06-03

    In pig, very little information is available on the non classical class I (Ib) genes of the Major Histocompatibility Complex (MHC) i.e. SLA-6, -7 and -8. Our aim was to focus on the transcription pattern of the SLA-7 gene. RT-PCR experiments were carried out with SLA-7 specific primers targeting either the full coding sequence (CDS) from exon 1 to the 3 prime untranslated region (3UTR) or a partial CDS from exon 4 to the 3UTR. We show that the SLA-7 gene expresses a full length transcript not yet identified that refines annotation of the gene with eight exons instead of seven as initially described from the existing RefSeq RNA. These two RNAs encode molecules that differ in cytoplasmic tail length. In this study, another SLA-7 transcript variant was characterized, which encodes a protein with a shorter alpha 3 domain, as a consequence of a splicing site within exon 4. Surprisingly, a cryptic non canonical GA-AG splicing site is used to generate this transcript variant. An additional SLA-7 variant was also identified in the 3UTR with a splicing site occurring 31 nucleotides downstream to the stop codon. In conclusion, the pig SLA-7 MHC class Ib gene presents a complex transcription pattern with two transcripts encoding various molecules and transcripts that do not alter the CDS and may be subject to post-transcriptional regulation.

  4. Molecular comparison of cattle fever ticks from native and introduced ranges with insights into optimal search areas for classical biological control agents

    Science.gov (United States)

    Classical biological control using specialist parasitoids, predators and/or nematodes from the native ranges of cattle fever ticks could complement existing control strategies for this livestock pest in the transboundary region between Mexico and Texas. DNA fingerprinting tools were used to compare ...

  5. 猪瘟病毒强弱毒株通用性RT-PCR检测方法研究进展%Advances in Research of General RT–PCR for Detection of Virulent and Weak Swine Fever Virus Strains

    Institute of Scientific and Technical Information of China (English)

    杨宗照; 王剑峰; 谢正; 李洪洲; 陈阳

    2012-01-01

      Classical swine fever(CSF)is an important pig disease,endangering the pig industry and causing large economic losses each year.In order to better control and prevention of this disease,timely diagnosis is very important.The diagnosis of CSFV includes virus isolation,RT-PCR and so on.This review focuses on the CSFV gene structure and its application in detection methods:conventional RT-PCR and real time RT-PCR.The conventional RT-PCR is inexpensive,but is laborious;the latter is just the reverse—need expensive fluorescent PCR machine but is quick and easy to do.The tendency of CSF diagnosis is automation and rapidness and can differentiate the wild-type CSFV from vaccine strains such as HCLV.%  猪瘟是一种严重危害养猪业的重大传染病,为了更好的防治本病,及时诊断尤为重要。猪瘟的诊断方法包括病毒分离、RT-PCR技术等。文章主要对猪瘟病毒基因结构、用于猪瘟检测的普通RT-PCR、荧光定量RT-PCR技术以及它们的优缺点和采样注意事项等作了概述。普通RT-PCR方法比较便宜但费力,而荧光定量RT-PCR方法恰恰相反,比较昂贵但省力。猪瘟检测的趋势是自动化和快速并最好同时能够区分野毒和疫苗株。

  6. 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.

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

    Science.gov (United States)

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

    2015-02-01

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

  8. 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)

    Howey, Erin B; O'Donnell, Vivian; de Carvalho Ferreira, Helena C; Borca, Manuel V; Arzt, Jonathan

    2013-12-26

    To investigate the pathogenesis of African swine fever virus (ASFV), domestic pigs (n=18) were challenged with a range (10(2)-10(6) 50% hemadsorbing doses (HAD50)) of the highly virulent ASFV-Malawi strain by inoculation via the intraoropharyngeal (IOP), intranasopharyngeal (INP), or intramuscular (IM) routes. A subsequent contact challenge experiment was performed in which six IOP-inoculated donor pigs were allowed to have direct contact (DC) with six naïve pigs for exposure times that varied from 24 to 72 h. All challenge routes resulted in clinical progression and postmortem lesions similar to those previously described in experimental and natural infection. The onset of clinical signs occurred between 1 and 7 days post inoculation (dpi) and included pyrexia with variable progression to obtundation, hematochezia, melena, moribundity and death with a duration of 4-11 days. Viremia was first detected between 4 and 5 dpi in all inoculation groups whereas ASFV shedding from the nasal cavity and tonsil was first detected at 3-9 dpi. IM and DC were the most consistent modes of infection, with 12/12 (100%) of pigs challenged by these routes becoming infected. Several clinical and virological parameters were significantly different between IM and DC groups indicating dissimilarity between these modes of infection. Amongst the simulated natural routes, INP inoculation resulted in the most consistent progression of disease across the widest range of doses whilst preserving simulation of natural exposure and therefore may provide a superior system for pathogenesis and vaccine efficacy investigation.

  9. 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.

  10. 猪瘟DNA疫苗研究进展%Progress in DNA vaccines against classical swine fever: a review

    Institute of Scientific and Technical Information of China (English)

    李娜; 孙元; 仇华吉

    2010-01-01

    自1990年DNA疫苗问世以来,已有许多研究者构建了不同类型的DNA疫苗.这些载体能诱发机体产生不同程度的特异性体液免疫和(或)细胞免疫.研究者们在猪瘟DNA疫苗研究方面做出了很多努力并取得了一定的成果.以下从猪瘟DNA疫苗的构建和评价、佐剂在猪瘟DNA疫苗中的应用、猪瘟DNA疫苗与其他疫苗的联合应用以及目前猪瘟DNA疫苗存在的问题和解决途径等方面做了比较全面的阐述.

  11. Nature Conservation and Veterinary Problems: Issues and Options. With case studies of foot and mouth disease and classical swine fever.

    OpenAIRE

    Butter, Maureen E.; Prent, K.

    2005-01-01

    Large herbivores in nature suffer from veterinary law In the Habitat Directive, Natura 2000, the EU aims at preservation, restoration and interconnection of large-scale nature reserves throughout the union. Such a network of interconnected wilderness will provide dearly needed space to large wild animals, many of which are declining or even in danger of extinction. A thousand years ago most of Europe was nature, providing space for aurochs, moose, wild horse, reindeer, wild boar, bear, wolf a...

  12. 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

    . It is essential that these plans are established during ‘peace-time’ and are reviewed regularly. This paper provides suggestions on how to perform laboratory exercises to test preparedness and describes the experiences of two national reference laboratories for CSF. The major lesson learnt was the importance...... contingency plans. These plans should ensure that in the event of an outbreak access to facilities, equipment, resources, trained personnel, and all other facilities needed for the rapid and efficient eradication of the outbreak is guaranteed, and that the procedures to follow are well rehearsed...... of a well-documented laboratory contingency plan. The major pitfalls encountered were shortage of space, difficulties in guaranteeing biosecurity and sufficient supplies of sterile equipment and consumables. The need for a standardised laboratory information management system, that is used by all those...

  13. 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...

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

    Science.gov (United States)

    Fernandez-Sainz, I; Ramanathan, P; O'Donnell, V; Diaz-San Segundo, F; Velazquez-Salinas, L; Sturza, D F; Zhu, J; de los Santos, T; Borca, M V

    2015-09-01

    Interferon-alpha (IFNα) can effectively inhibit or abort a viral infection within the host. It has been reported that IFN induction and production is hindered during classical swine fever virus (CSFV) infection. Most of those studies have been performed in vitro, making it difficult to elucidate the actual role of IFNs during CSFV infection in swine. Here, we report the effect of IFNα treatment (delivered by a replication defective recombinant human adenovirus type 5, Ad5) in swine experimentally infected with highly virulent CSFV strain Brescia. Treatment with two different subtypes of IFNα delayed the appearance of CSF-related clinical signs and virus replication although it did not prevent lethal disease. This is the first report describing the effect of IFNα treatment during CSFV infection in swine. PMID:26004252

  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. Wild and Domestic Pig Interactions at the Wildlife–Livestock Interface of Murchison Falls National Park, Uganda, and the Potential Association with African Swine Fever Outbreaks

    Science.gov (United States)

    Kukielka, Esther A.; Jori, Ferran; Martínez-López, Beatriz; Chenais, Erika; Masembe, Charles; Chavernac, David; Ståhl, Karl

    2016-01-01

    Bushpigs (BPs) (Potamochoerus larvatus) and warthogs (WHs) (Phacochoerus africanus), which are widely distributed in Eastern Africa, are likely to cohabitate in the same environment with domestic pigs (DPs), facilitating the transmission of shared pathogens. However, potential interactions between BP, WH, and DP, and the resulting potential circulation of infectious diseases have rarely been investigated in Africa to date. In order to understand the dynamics of such interactions and the potential influence of human behavior and husbandry practices on them, individual interviews (n = 233) and participatory rural appraisals (n = 11) were carried out among Ugandan pig farmers at the edge of Murchison Falls National Park, northern Uganda. In addition, as an example of possible implications of wild and DP interactions, non-linear multivariate analysis (multiple correspondence analyses) was used to investigate the potential association between the aforementioned factors (interactions and human behavior and practices) and farmer reported African swine fever (ASF) outbreaks. No direct interactions between wild pigs (WPs) and DP were reported in our study area. However, indirect interactions were described by 83 (35.6%) of the participants and were identified to be more common at water sources during the dry season. Equally, eight (3.4%) farmers declared exposing their DP to raw hunting leftovers of WPs. The exploratory analysis performed suggested possible associations between the farmer reported ASF outbreaks and indirect interactions, free-range housing systems, dry season, and having a WH burrow less than 3 km from the household. Our study was useful to gather local knowledge and to identify knowledge gaps about potential interactions between wild and DP in this area. This information could be useful to facilitate the design of future observational studies to better understand the potential transmission of pathogens between wild and DPs. PMID:27148545

  17. Increase in chemokines CXCL10 and CCL2 in blood from pigs infected with high compared to low virulence African swine fever virus isolates.

    Science.gov (United States)

    Fishbourne, Emma; Hutet, Evelyne; Abrams, Charles; Cariolet, Roland; Le Potier, Marie-Frédérique; Takamatsu, Haru-H; Dixon, Linda K

    2013-10-01

    Modulation of the expression of chemokines and chemokine receptors in whole blood was compared following infection of pigs with high and low virulence isolates of African swine fever virus. Levels of mRNAs for CCL2, CCL3L1, CCL4, CXCL10, CCR1 and CCR5 were significantly increased in at least one time point following infection in two experiments and CCL5, CCR9 and CXCR4 mRNA were significantly increased in one of the experiments. The results showed that greatest fold increases in mRNAs for CXCL10 and CCL2 were observed following infection of pigs. CXCL10 mRNA was increased by up to 15 fold in infected compared to uninfected pigs. CXCL10 protein was also detected in serum from pigs infected with the high virulence Benin 97/1 isolate. Levels of CCL2 mRNA were increased in pigs infected with high virulence Benin 97/1 isolate compared to low virulence OURT88/3 isolate and this correlated with an increase of greater than 30 fold in levels of CCL2 protein detected in serum from pigs infected with this isolate. An increase in overall chemotaxis active compounds in defibrinated plasma samples from Benin 97/1 infected pigs was observed at 3 days post-infection (dpi) and a decrease by 7 dpi as measured by chemotaxis assay using normal pig leucocytes in vitro. Increased levels of CXCL10 may either contribute to the activation of lymphocyte priming toward the Th1 phenotype or induction of T lymphocyte apoptosis. Increased levels of CCL2, a chemoattractant for macrophages, may result in increased recruitment of monocytes from bone marrow thus increasing the pool of cells susceptible to infection.

  18. 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

  19. Wild and Domestic Pig Interactions at the Wildlife-Livestock Interface of Murchison Falls National Park, Uganda, and the Potential Association with African Swine Fever Outbreaks.

    Science.gov (United States)

    Kukielka, Esther A; Jori, Ferran; Martínez-López, Beatriz; Chenais, Erika; Masembe, Charles; Chavernac, David; Ståhl, Karl

    2016-01-01

    Bushpigs (BPs) (Potamochoerus larvatus) and warthogs (WHs) (Phacochoerus africanus), which are widely distributed in Eastern Africa, are likely to cohabitate in the same environment with domestic pigs (DPs), facilitating the transmission of shared pathogens. However, potential interactions between BP, WH, and DP, and the resulting potential circulation of infectious diseases have rarely been investigated in Africa to date. In order to understand the dynamics of such interactions and the potential influence of human behavior and husbandry practices on them, individual interviews (n = 233) and participatory rural appraisals (n = 11) were carried out among Ugandan pig farmers at the edge of Murchison Falls National Park, northern Uganda. In addition, as an example of possible implications of wild and DP interactions, non-linear multivariate analysis (multiple correspondence analyses) was used to investigate the potential association between the aforementioned factors (interactions and human behavior and practices) and farmer reported African swine fever (ASF) outbreaks. No direct interactions between wild pigs (WPs) and DP were reported in our study area. However, indirect interactions were described by 83 (35.6%) of the participants and were identified to be more common at water sources during the dry season. Equally, eight (3.4%) farmers declared exposing their DP to raw hunting leftovers of WPs. The exploratory analysis performed suggested possible associations between the farmer reported ASF outbreaks and indirect interactions, free-range housing systems, dry season, and having a WH burrow less than 3 km from the household. Our study was useful to gather local knowledge and to identify knowledge gaps about potential interactions between wild and DP in this area. This information could be useful to facilitate the design of future observational studies to better understand the potential transmission of pathogens between wild and DPs. PMID:27148545

  20. Protection of mice against lethal challenge with 2009 H1N1 influenza A virus by 1918-like and classical swine H1N1 based vaccines.

    Directory of Open Access Journals (Sweden)

    Balaji Manicassamy

    2010-01-01

    Full Text Available The recent 2009 pandemic H1N1 virus infection in humans has resulted in nearly 5,000 deaths worldwide. Early epidemiological findings indicated a low level of infection in the older population (>65 years with the pandemic virus, and a greater susceptibility in people younger than 35 years of age, a phenomenon correlated with the presence of cross-reactive immunity in the older population. It is unclear what virus(es might be responsible for this apparent cross-protection against the 2009 pandemic H1N1 virus. We describe a mouse lethal challenge model for the 2009 pandemic H1N1 strain, used together with a panel of inactivated H1N1 virus vaccines and hemagglutinin (HA monoclonal antibodies to dissect the possible humoral antigenic determinants of pre-existing immunity against this virus in the human population. By hemagglutinination inhibition (HI assays and vaccination/challenge studies, we demonstrate that the 2009 pandemic H1N1 virus is antigenically similar to human H1N1 viruses that circulated from 1918-1943 and to classical swine H1N1 viruses. Antibodies elicited against 1918-like or classical swine H1N1 vaccines completely protect C57B/6 mice from lethal challenge with the influenza A/Netherlands/602/2009 virus isolate. In contrast, contemporary H1N1 vaccines afforded only partial protection. Passive immunization with cross-reactive monoclonal antibodies (mAbs raised against either 1918 or A/California/04/2009 HA proteins offered full protection from death. Analysis of mAb antibody escape mutants, generated by selection of 2009 H1N1 virus with these mAbs, indicate that antigenic site Sa is one of the conserved cross-protective epitopes. Our findings in mice agree with serological data showing high prevalence of 2009 H1N1 cross-reactive antibodies only in the older population, indicating that prior infection with 1918-like viruses or vaccination against the 1976 swine H1N1 virus in the USA are likely to provide protection against the 2009

  1. 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; Prisk 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; Pcontrol were positively associated with ASF infection of Nigerian farms (OR=4.94; CI(95%)=1.84, 13.29; P=0.002). The presentation of sick and unthrifty pigs for slaughter at abattoirs, farmers' inadvertent role, an infected neighbourhood, a pig to pig contact, rodents and wild birds may contribute to infections of farms, whereas washing, disinfection of tools, food and water control, and

  2. 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

  3. Pathological Changes and Etiological Study of the Swine High Fever Syndrome (SHFS) in Central Region of Shandong Province%鲁中地区猪高热性疾病的病理变化及病原学调查研究

    Institute of Scientific and Technical Information of China (English)

    刘月月; 杜以军; 王金宝; 刘思当; 吴家强; 任庆海; 张绍武; 吴好庭; 张玉玉; 赵鹏伟; 彭军; 李俊

    2012-01-01

    In order to study the pathological changes and the etiological agent of the Swine High Fever Syndrome (SHFS) in central region of Shandong province, we diagnosed the clinical symptoms and the pathological changes of 109 cases in 56 pig farms and collected 363 serum samples from Jan. 2011 to Mar. 2012. Three viruses were detected on tissue samples by histopathologi-cal, immunohistochemical examination and RT-PCR or PCR, including classical swine fever virus (CSFV) ,porcine reproductive and respiratory syndrome virus (PRRSV) , porcine circovirus type 2 (PCV-2). Serological tests were used for detecting prevalence of CSFV,PRRS, and PCV- 2 antibody by ELISA. The results showed that all pigs suffering from high fever had been vaccinated by Classical Swine Fever vaccines, part by Porcine Reproductive and Respiratory Syndrome attenuated live vaccines, but none by Circovirus vaccines. However, they had high positive rates of antibody against CSFV,PRRSV, and PCV-2. The pathological changes mainly included acute inflammation in lymphoid tissues, interstitial pneumonia and viral encephalitis, and the occurrences were respectively 92. 3%, 76. 1% and 66. 1%. The pathogenetic rates of CSFV, PRRSV and PCV2 were respectively 30. 27% , 66. 97% and 41. 28%. Co-infection rates of CSFV and PRRSV, CSFV and PCV2, PRRSV and PCV2 were respectively 16. 51%, 6. 42% and 28. 44%. And the triple infection rate was 4. 59%. In addition, other pathogenic infections were 8. 26%. Sequence analysis showed that the epidemic strains of CSFV were developing towards being far away from the HCLV, PRRSV strains were highly pathogenic ones, and PCV2 strains were mainly the virulent Type-PCV2b. In conclusion, CSFV, PRRSV and PCV2 were the main pathogens which caused the Swine High Fever in central region of Shandong province, and the severe cases were mainly caused by co-infection. What's more, mixed infection of Mycoplasma and Haemophilus parasuis used to occur in clinical cases. Therefore, the Swine High

  4. Efficacy of a high-growth reassortant H1N1 influenza virus vaccine against the classical swine H1N1 subtype influenza virus in mice and pigs.

    Science.gov (United States)

    Wen, Feng; Yu, Hai; Yang, Fu-Ru; Huang, Meng; Yang, Sheng; Zhou, Yan-Jun; Li, Ze-Jun; Tong, Guang-Zhi

    2014-11-01

    Swine influenza (SI) is an acute, highly contagious respiratory disease caused by swine influenza A viruses (SwIVs), and it poses a potential global threat to human health. Classical H1N1 (cH1N1) SwIVs are still circulating and remain the predominant subtype in the swine population in China. In this study, a high-growth reassortant virus (GD/PR8) harboring the hemagglutinin (HA) and neuraminidase (NA) genes from a novel cH1N1 isolate in China, A/Swine/Guangdong/1/2011 (GD/11) and six internal genes from the high-growth A/Puerto Rico/8/34(PR8) virus was generated by plasmid-based reverse genetics and tested as a candidate seed virus for the preparation of an inactivated vaccine. The protective efficacy of this vaccine was evaluated in mice and pigs challenged with GD/11 virus. Prime and boost inoculation of GD/PR8 vaccine yielded high-titer serum hemagglutination inhibiting (HI) antibodies and IgG antibodies for GD/11 in both mice and pigs. Complete protection of mice and pigs against cH1N1 SIV challenge was observed, with significantly fewer lung lesions and reduced viral shedding in vaccine-inoculated animals compared with unvaccinated control animals. Our data demonstrated that the GD/PR8 may serve as the seed virus for a promising SwIVs vaccine to protect the swine population.

  5. 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

  6. 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...

  7. Finding a new drug and vaccine for emerging swine flu: What is the concept?

    Directory of Open Access Journals (Sweden)

    Viroj Wiwanitkit

    2009-08-01

    Full Text Available Viroj WiwanitkitWiwanitkit House, Bangkhae, Bangkok 10160Abstract: Influenza is a well known infection of the respiratory system. The main clinical manifestations of influenza include fever, sore throat, headache, cough, coryza, and malaise. Apart from the well known classical influenza, there are also groups of influenza virus infections that are called “atypical infection”. These infections are usually due to a novel influenza virus infection. In early 2009, an emerging novel influenza originating from Mexico called swine flu was reported. The World Health Organization noted a level VI precaution, the highest level precaution possible, for this newest influenza virus infection. As of June 2009, it is not known if this disease will be successfully controlled. Finding new drugs and vaccine for the emerging swine flu is still required to cope with this emerging worldwide problem.Keywords: swine flu, drug, vaccine, concept

  8. 南安市近三年猪瘟免疫抗体检测结果分析%Results and Analysis of swine fever pig disease immune antibody in Nanan city

    Institute of Scientific and Technical Information of China (English)

    王硕; 黄延招

    2015-01-01

    2012-2014 Swine fever immune antibody qualification rate were 86.28%, 88.49% and 94.77%. Antibody qualification rate from high to low according to the field scale, backyard households, slaughterhouse;Breeding scale is larger, the higher antibody quali-fication rate.%2012-2014年南安市猪瘟免疫抗体合格率分别为86.28%、88.49%和94.77%。免疫抗体合格率从高到低依次为规模场、散养户、屠宰场;养殖规模越大,抗体合格率越高。

  9. Immunization Efficiency of Swine Fever Live Vaccine(Spleen and lymph tissue origin),Swine Foot and Mouth Disease (Type O) Inactivated Vaccine,Porcine Reproductive and Respiratory Syndrome(PRRS) Inactivated Vaccine%3种疫苗单独和联合免疫对猪抗体水平的影响

    Institute of Scientific and Technical Information of China (English)

    窦鹏勋; 张红梅; 雷祥前; 葛建强; 张勇; 杨增歧; 韩斌; 贾燕青; 冯磊; 南风; 白永平

    2009-01-01

    [目的]寻求有效结合注射的新型免疫程序,以有效控制猪瘟(CSF)、猪口蹄疫(FMD)和猪繁殖与呼吸综合征(PRRS)疫情的发生和流行.[方法]在陕西省横山和米脂两县将140头猪随机分为7组,每组20头,采用CSF活疫苗(脾淋源)、FMD灭活疫苗(0型Ⅱ)、PRRS灭活疫苗(NVDC-JXA1株)分别进行单独、2种及3种同时分点免疫注射试验,用正向间接血凝和ELISA法检测猪抗体水平.[结果]①3种疫苗都可以刺激猪产生特异性抗体,并且抗体在21、28和35 d呈规律性增长.②CSF疫苗与FMD、PRRS疫苗分开和三者同时使用时,虽然FMD、PRRS疫苗推迟CSF抗体的上升时间,但是对CSF的免疫效果产生的影响不明显.③PRRS与FMD疫苗同时注射后,所产生抗体效价在21、28和35 d均比单独注射PRRS疫苗阳性率高,说明FMD疫苗可对PRRS疫苗注射后有效抗体的产生达到积极协同作用,促进PRRS有效免疫抗体的产生,同时免疫CSF疫苗和PRRS疫苗的抗体水平低于单独注射PRRS疫苗,说明共同免疫CSF和PRRS疫苗时,2种疫苗会相互影响,使免疫效果不如单独免疫.④FMD和PRRS疫苗同时注射后,FMD疫苗所产生的抗体水平(OD值)最高,且一直呈上升趋势,优于FMD疫苗单独注射所产生的抗体水平,说明FMD和PRRS疫苗同时注射,更能促进FMD抗体的产生.[结论]3种疫苗同时分点注射和单注CSF产生抗体后再同时分点注射FMD和PRRS都是较好的防疫体系,具体应根据养殖规模及地域选择合适的防疫体系.%[Objective] The aim was to seek a new effective pattern of immune procedure in order to effectively control epidemic situation of classical swine fever (CSF),swine foot-and-mouth disease (FMD) and porcine reproductive and respiratory syndrome (PRRS) in Yulin district. [ Method] In Hengshan and Mizhi County of Shaanxi Province, 140 pigs were divided into 7 groups randomly ,20 pigs in each group. In immune experiment, we applied CSF live vaccine

  10. 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...

  11. Swine Influenza (Swine Flu) in Pigs

    Science.gov (United States)

    ... Documents (General) Workers Employed at Commercial Swine Farms Influenza Types Seasonal Avian Swine Variant Pandemic Other Get ... Submit Button Past Newsletters Key Facts about Swine Influenza (Swine Flu) in Pigs Questions & Answers Language: English ...

  12. Phylogenetic analysis of NS5B gene of classical swine fever virus isolates indicates plausible Chinese origin of Indian subgroup 2.2 viruses.

    Science.gov (United States)

    Patil, S S; Hemadri, D; Veeresh, H; Sreekala, K; Gajendragad, M R; Prabhudas, K

    2012-02-01

    Twenty-three CSFV isolates recovered from field outbreaks in various parts of India during 2006-2009 were used for genetic analysis in the NS5B region (409 nts). Seventeen of these were studied earlier [16] in the 5'UTR region. Phylogenetic analysis indicated the continued dominance of subgroup 1.1 strains in the country. Detailed analysis of a subgroup 2.2 virus indicated the plausible Chinese origin of this subgroup in India and provided indirect evidence of routes of CSFV movement within South East Asia region.

  13. Pathway analysis in blood cells of pigs infected with classical swine fever virus: comparison of pigs that develop a chronic form of infection or recover.

    Science.gov (United States)

    Hulst, Marcel; Loeffen, Willie; Weesendorp, Eefke

    2013-02-01

    Infection of pigs with CSFV can lead to either acute disease, resulting in death or recovery, or chronic disease. The mechanisms by which CSFV manipulates the pig's first line of defence to establish a chronic infection are poorly understood. Therefore, pigs were infected with moderately virulent CSFV, and whole blood was collected on a regular basis during a period of 18 days. Using whole-genome microarrays, time-dependent changes in gene expression were recorded in blood cells of chronically diseased pigs and pigs that recovered. Bioinformatics analysis of regulated genes indicated that different immunological pathways were regulated in chronically diseased pigs compared to recovered pigs. In recovered pigs, antiviral defence mechanisms were rapidly activated, whereas in chronically diseased pigs, several genes with the potential to inhibit NF-κB- and IRF3/7-mediated transcription of type I interferons were up-regulated. Compared to recovered pigs, chronically diseased pigs failed to activate NK or cytotoxic T-cell pathways, and they showed decreased gene activity in antigen-presenting monocytes/macrophages. Remarkably, in chronically diseased pigs, genes related to the human autoimmune disease systemic lupus erythematosus (SLE) were up-regulated during the whole period of 18 days. CSFV pathology in kidney and skin resembles that of SLE. Furthermore, enzymes involved in the degradation of 1,25-dihydroxyvitamin D3 and of tryptophan to kynurenines were expressed at different levels in chronically diseased and recovered pigs. Both of these chemical processes may affect the functions of T helper/regulatory cells that are crucial for tempering the inflammatory response after a viral infection.

  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

    , are 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...

  15. 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

    animals, the so called DIVA principle. This inability complicates monitoring of disease and stops international trade thereby limiting use of the vaccine in many regions. The C-strain vaccine is safe to use and gives good protection. It is licensed for emergency vaccination in the EU in event...

  16. 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

  17. Co-expression of the C-terminal domain of Yersinia enterocolitica invasin enhances the efficacy of classical swine-fever-vectored vaccine based on human adenovirus

    Indian Academy of Sciences (India)

    Helin Li; Pengbo Ning; Zhi Lin; Wulong Liang; Kai Kang; Lei He; Yanming Zhang

    2015-03-01

    The use of adenovirus vector-based vaccines is a promising approach for generating antigen-specific immune responses. Improving vaccine potency is necessary in other approaches to address their inadequate protection for the majority of infectious diseases. This study is the first to reconstruct a recombinant replication-defective human adenovirus co-expressing E2 and invasin C-terminal (InvC) glycoproteins (rAd-E2-InvC). rAd-E2-InvC with 2×106 TCID50 was intramuscularly administered two times to CSFV-free pigs at 14 day intervals. No adverse clinical reactions were observed in any of the pigs after the vaccination. The CSFV E2-specific antibody titer was significantly higher in the rAd-E2-InvC group than that in the rAdV-E2 group as measured by NPLA and blocking ELISA. Pigs immunized with rAd-E2-InvC were completely protected against lethal challenge. Neither CSFV RNA nor pathological changes were detected in the tissues after CSFV challenge. These results demonstrate that rAd-E2-InvC could be an alternative to the existing CSF vaccine. Moreover, InvC that acts as an adjuvant could enhance the immunogenicity of rAdV-E2 and induce high CSFV E2-specific antibody titer and protection level.

  18. Chimeric classical swine fever (CSF)-Japanese encephalitis (JE) viral particles as a non-transmissible bivalent marker vaccine candidate against CSF and JE infections

    Science.gov (United States)

    A trans-complemented CSF- JE chimeric viral replicon was constructed using an infectious cDNA clone of the CSF virus (CSFV) Alfort/187 strain. The E2 gene of CSFV Alfort/187 strain was deleted and the resultant plasmid pA187delE2 was inserted by a fragment containing the region coding for a truncate...

  19. Persistentie van KVP-virus in gevaccineerde dieren: een risico? = Persistence of classical swine fever virus in vaccinated animals: a risk?

    NARCIS (Netherlands)

    Loeffen, W.L.A.

    2008-01-01

    Het is dit jaar geleden dat in Nederland het geval van klassieke varkenspest werd gedetecteerd. Het was het laatste geval in een epidemie die ruim een jaar had geduurd. Op dat moment waren we 429 besmette bedrijven verder, waren 12 miljoen varkens vernietigd en was de schade opgelopen tot meer dan 2

  20. 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