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Sample records for swine fever infections

  1. 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...

  2. African swine fever virus infection in Classical swine fever subclinically infected wild boars.

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    Cabezón, Oscar; Muñoz-González, Sara; Colom-Cadena, Andreu; Pérez-Simó, Marta; Rosell, Rosa; Lavín, Santiago; Marco, Ignasi; Fraile, Lorenzo; de la Riva, Paloma Martínez; Rodríguez, Fernando; Domínguez, Javier; Ganges, Llilianne

    2017-08-01

    Recently moderate-virulence classical swine fever virus (CSFV) strains have been proven capable of generating postnatal persistent infection (PI), defined by the maintenance of viremia and the inability to generate CSFV-specific immune responses in animals. These animals also showed a type I interferon blockade in the absence of clinical signs. In this study, we assessed the infection generated in 7-week-old CSFV PI wild boars after infection with the African swine fever virus (ASFV). The wild boars were divided in two groups and were infected with ASFV. Group A comprised boars who were CSFV PI in a subclinical form and Group B comprised pestivirus-free wild boars. Some relevant parameters related to CSFV replication and the immune response of CSFV PI animals were studied. Additionally, serum soluble factors such as IFN-α, TNF-α, IL-6, IL-10, IFN-γ and sCD163 were analysed before and after ASFV infection to assess their role in disease progression. After ASFV infection, only the CSFV PI wild boars showed progressive acute haemorrhagic disease; however, the survival rates following ASFV infection was similar in both experimental groups. Notwithstanding, the CSFV RNA load of CSFV PI animals remained unaltered over the study; likewise, the ASFV DNA load detected after infection was similar between groups. Interestingly, systemic type I FN-α and IL-10 levels in sera were almost undetectable in CSFV PI animals, yet detectable in Group B, while detectable levels of IFN-γ were found in both groups. Finally, the flow cytometry analysis showed an increase in myelomonocytic cells (CD172a + ) and a decrease in CD4 + T cells in the PBMCs from CSFV PI animals after ASFV infection. Our results showed that the immune response plays a role in the progression of disease in CSFV subclinically infected wild boars after ASFV infection, and the immune response comprised the systemic type I interferon blockade. ASFV does not produce any interference with CSFV replication, or vice

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

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    Guo Huan-cheng

    2011-03-01

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

  4. Transcriptional immunoresponse of tissue-specific macrophages in swine after infection with African swine fever virus

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    Kowalczyk Andrzej

    2015-12-01

    Full Text Available Macrophages and cytokines are important in the control of inflammation and regulation of the immune response. However, they can also contribute to immunopathology in the host after viral infection and the regulatory network can be subverted by infectious agents, including viruses, some of which produce cytokine analogues or have mechanisms that inhibit cytokine function. African swine fever virus (ASFV encodes a number of proteins which modulate cytokine and chemokine induction, host transcription factor activation, stress responses, and apoptosis. The aim of this review is to elucidate the mechanisms of immune responses to ASFV in different subpopulations of porcine macrophages. A transcriptional immune response in different resident tissue macrophages following ASFV infection was presented in many publications. ASFV-susceptible porcine macrophages can be of several origins, such as peripheral blood, lungs, bone marrow, etc. blood monocytes, blood macrophages, and lung macrophages have demonstrated a modulation of phenotype. Monocyte-derived macrophages could express surface markers not found on their monocyte precursors. Moreover, they can undergo further differentiation after infection and during inflammation. When viruses infect such cells, immunological activity can be seriously impaired or modified.

  5. Time-dependent infection probability of classical swine fever via excretions and secretions

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    Weesendorp, E.; Loeffen, W.L.A.; Stegeman, A.; Vos, de C.J.

    2011-01-01

    Several routes contribute to the spread of classical swine fever (CSF) during outbreaks of this disease. However, for many infected herds in recent epidemics, no route of virus introduction could be indentified. To obtain more insight into the relative importance of secretions and excretions in

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

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    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.

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

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

    2017-01-01

    In 2014, African swine fever virus (ASFV) was introduced into the Baltic states and Poland. Since then, the disease has continued to spread within these regions, and recently, cases were reported in the Czech Republic and Romania. Currently, there is an increasing risk of ASFV introduction...... inoculation, by direct contact to infected animals and by aerosol developed acute disease characterized by viremia, fever and depression. Infectious virus was first detected in blood obtained from the inoculated pigs and then sequentially among the within-pen, between-pen and air-contact pigs. ASFV DNA...

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

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    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.

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

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

    2009-11-18

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

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

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    2011-01-01

    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. PMID:21535885

  11. Disruption of Nuclear Organization during the Initial Phase of African Swine Fever Virus Infection

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    Ballester, Maria; Rodríguez-Cariño, Carolina; Pérez, Mónica; Gallardo, Carmina; Rodríguez, Javier M.; Salas, María L.; Rodriguez, Fernando

    2011-01-01

    African swine fever virus (ASFV), the causative agent of one of the most devastating swine diseases, has been considered exclusively cytoplasmic, even though some authors have shown evidence of an early stage of nuclear replication. In the present study, an increment of lamin A/C phosphorylation was observed in ASFV-infected cells as early as 4 h postinfection, followed by the disassembling of the lamina network close to the sites where the viral genome starts its replication. At later time points, this and other nuclear envelope markers were found in the cytoplasm of the infected cells. The effect of the infection on the cell nucleus was much more severe than previously expected, since a redistribution of other nuclear proteins, such as RNA polymerase II, the splicing speckle SC-35 marker, and the B-23 nucleolar marker, was observed from 4 h postinfection. All this evidence, together with the redistribution, dephosphorylation, and subsequent degradation of RNA polymerase II after ASFV infection, suggests the existence of sophisticated mechanisms to regulate the nuclear machinery during viral infection. PMID:21680527

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

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    Sun, Yuan; Jiang, Qian; Tian, Da-Yong; Lin, Huan; Li, Hong; Han, Qiu-Ying; Han, Wen; Si, Chang-De; Hu, Shou-Ping; Zhang, Zhuo; Qu, Lian-Dong; Qiu, Hua-Ji

    2011-09-25

    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. 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. 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.

  13. [Effect of experimental classical swine fever (CSF) infection on libido and ejaculate parameters in boars].

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    Wehrend, A; Fritzemeier, J; Flögel-Niesmann, G; Mönnig, V; Hollen-Horst, M; Meinecke, B

    2006-07-01

    The objective of this study was to characterize the effect of an experimental infection with the classical swine fever (CSF) virus on libido and ejaculate parameters of adult boars. Four boars 10 month old were infected with a CSF field isolate (Visbek/Han95). Semen was collected every second day after infection and daily during the pyrexic phase. The only clinical signs in the boars were an increase in body temperature, but never above 39.9 degrees C and a temporally reduction of food intake. The libido was always good, so semen collection was performed in three boars without difficulty and the semen quality was always in the range of the minimum requirements for sperm that is used for artificial insemination. Although one boar had a good libido only a sperm free ejaculate could be collected on one day. The results show that a CSF virus infection of adult boars hardly causes any clinical symptoms and that sperm can be obtained despite fever. Insemination boars may thus be of special epidemiological relevance for the dissemination of the CSF virus.

  14. Does the infection with endoparasites influence the effect of oral vaccination against classical swine fever in wild boar?

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    Anna Ondrejková

    2015-01-01

    Full Text Available Classical swine fever is a highly contagious viral disease that affects domestic and wild suids and could cause important economic losses. It is the most dangerous infectious disease of the wild boar that can cause severe death in densely populated areas. The aim of the study was to determine the effect of endoparasites on the oral vaccination against classical swine fever in wild boar. The study compared classical swine fever antibody titres in wild boar treated and untreated with antiparasitics. Fourteen six-month-old wild boar piglets were tested via direct ELISA to detect specific antibodies in blood serum after vaccination. Before the vaccination, one group of piglets was administered antiparasitic therapy; the other group of animals remained untreated. Twenty-eight days post vaccination, piglets from the first group (free of parasites showed significantly (P = 0.0015 higher concentrations of specific antibodies than the infected animals. Obtained results proved that parasitic infections substantially influence the efficacy of oral vaccination against classical swine fever and may support the ability of the virus to produce infectious diseases and its transmission in the wild boar population. For that reason, antiparasitic therapy of wild boar populations before their vaccination is highly recommended in order to increase the vaccine’s efficacy.

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

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    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

  16. Time-dependent infection probability of classical swine fever via excretions and secretions.

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    Weesendorp, Eefke; Loeffen, Willie; Stegeman, Arjan; de Vos, Clazien

    2011-02-01

    Several routes contribute to the spread of classical swine fever (CSF) during outbreaks of this disease. However, for many infected herds in recent epidemics, no route of virus introduction could be indentified. To obtain more insight into the relative importance of secretions and excretions in transmission of CSF virus, a model was developed. This model quantified the daily transmission probabilities from one infectious pig to one susceptible pig, using quantitative data on: (a) virus excretion by infected pigs, (b) survival of virus in the environment and (c) virus dose needed to infect susceptible pigs. Furthermore, the model predicted the relative contribution of secretions and excretions to this daily probability of infection of a susceptible pig. Three virus strains that differed in virulence were evaluated with the model: the highly virulent strain Brescia, the moderately virulent strain Paderborn and the low virulent strain Zoelen. Results suggest that it is highly probable that susceptible pigs in contact with Brescia or Paderborn infected pigs will be infected. For a pig in contact with a Zoelen infected pig, infection is less likely. When contact with blood is excluded, the predicted overall probability of infection was only 0.08 over the entire infectious period. The three strains differed in the relative contribution of secretions and excretions to transmission, although blood had a high probability of causing infection of a susceptible pig when in contact with a pig infected with any strain. This supports the statement that during outbreaks, control measures should ideally be based on the characteristics of the specific virus strain involved, which implies the development of strain-specific measures. Copyright © 2010 Elsevier B.V. All rights reserved.

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

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    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.

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

    DEFF Research Database (Denmark)

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

    2012-01-01

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

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

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    Zaven Karalyan

    2016-12-01

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

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

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    Karalyan, Zaven; Zakaryan, Hovakim; Arakelova, Elina; Aivazyan, Violeta; Tatoyan, Marina; Kotsinyan, Armen; Izmailyan, Roza; Karalova, Elena

    2016-12-01

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

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

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

    2015-01-01

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

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

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    M. A. Sargsyan

    2018-01-01

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

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

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    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...

  4. Influence of Age and Dose of African Swine Fever Virus Infections on Clinical Outcome and Blood Parameters in Pigs.

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    Post, Jacob; Weesendorp, Eefke; Montoya, Maria; Loeffen, Willie L

    African swine fever (ASF) is a fatal disease for domestic pigs, leading to serious economic losses in countries where ASF is endemic. Despite extensive research, efficient vaccines against ASF are lacking. Since peripheral blood cells are important mediators for vaccines, we study the impact of ASF on blood parameters in pigs with different ages and infected with different doses of ASF virus. Four different groups were studied: (1) 12 weeks of age/low virus dose; (2) 12 weeks of age/high virus dose; (3) 18 weeks of age/low virus dose; and (4) 18 weeks of age/high virus dose. By varying in age and/or ASFV inoculation dose, we monitor blood parameters during different degrees of disease. Thirty percent of the pigs survived the infection with a moderately virulent strain of African swine fever virus (ASFV). Animals that did survive infection were generally older, independent from the inoculation dose used. A firm reduction in many different cell types at 3-5 days postinfection (DPI) was accompanied by an increase in body temperature, followed by clinical signs and mortality from day 6 PI. While blood parameters generally normalized in survivors, γδ T cells and IL-10 levels could be related to mortality. These conclusions should be considered in new approaches for protection against ASF.

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

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

    2009-01-01

    Classical swine fever virus (CSFV) is transmitted via secretions and excretions of infected pigs. The efficiency and speed of the transmission depends oil a multitude of parameters, like quantities Of Virus excreted by infected Pigs. ThiS study provides quantitative data oil excretion of CSFV over

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

    DEFF Research Database (Denmark)

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

    2013-01-01

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

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

    DEFF Research Database (Denmark)

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

    2010-01-01

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

  8. Genetically edited pigs lacking CD163 show no resistance following infection with the African swine fever virus isolate, Georgia 2007/1.

    Science.gov (United States)

    Popescu, Luca; Gaudreault, Natasha N; Whitworth, Kristen M; Murgia, Maria V; Nietfeld, Jerome C; Mileham, Alan; Samuel, Melissa; Wells, Kevin D; Prather, Randall S; Rowland, Raymond R R

    2017-01-15

    African swine fever is a highly contagious, often fatal disease of swine for which there is no vaccine or other curative treatment. The macrophage marker, CD163, is a putative receptor for African swine fever virus (ASFV). Pigs possessing a complete knockout of CD163 on macrophages were inoculated with Georgia 2007/1, a genotype 2 isolate. Knockout and wild type pen mates became infected and showed no differences in clinical signs, mortality, pathology or viremia. There was also no difference following in vitro infection of macrophages. The results do not rule out the possibility that other ASFV strains utilize CD163, but demonstrate that CD163 is not necessary for infection with the Georgia 2007/1 isolate. This work rules out a significant role for CD163 in ASFV infection and creates opportunities to focus on alternative receptors and entry mechanisms. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  9. 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

    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 ...

  10. 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.

  11. Post-Natal Persistent Infection With Classical Swine Fever Virus in Wild Boar: A Strategy for Viral Maintenance?

    Science.gov (United States)

    Cabezón, O; Colom-Cadena, A; Muñoz-González, S; Pérez-Simó, M; Bohórquez, J A; Rosell, R; Marco, I; Domingo, M; Lavín, S; Ganges, L

    2017-04-01

    In this study, fifteen wild boar piglets were intranasally inoculated classical swine fever virus (CSFV) strain Catalonia 01. At 5 days post-inoculation, seven other animals within 48 h of birth were put in contact with them. Viral replication and innate and specific immune responses were evaluated. Of the inoculated animals, 46.67% remained post-natally persistently infected and were apparently healthy with neither humoral nor cellular immunological responses specific to CSFV and with high viral loads in their blood, organs and body secretions. Moreover, the present data extend the time period to 48 h after birth when a moderately virulent CSFV strain could lead to post-natal persistent infection given the generation of persistently infected wild boars in the contact group (33.33%). The innate immune response to the virus, as measured by type I IFN-α in serum, was mostly not impaired in the persistently infected wild boars. Interestingly, a decrease and lack of IFN-γ-producing cells against CSFV and PHA was observed. In endemic countries where wild swine species are increasing and low and moderate virulence CSFV strains are prevalent, the possible generation of this form of disease cannot be ruled out. © 2015 Blackwell Verlag GmbH.

  12. Experimental infection of pregnant sows with African swine fever (ASFV Georgia 2007): Clinical outcome, pathogenesis and vertical transmission

    DEFF Research Database (Denmark)

    Lohse, Louise; Strandbygaard, Bertel; Nielsen, Jens

    African swine fever virus (ASFV) causes a severe hemorrhagic fever in domestic pigs. The disease was introduced from the African continent to Georgia in 2007 and has since spread throughout the Caucasus and the Russian Federation. ASF is now established in Eastern Europe and outbreaks have occurred...

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

    DEFF Research Database (Denmark)

    Widén, F.; Everett, H.; Blome, S.

    2014-01-01

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

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

    Science.gov (United States)

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

    2016-07-01

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

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

    Science.gov (United States)

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

    2008-12-10

    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 mechanical vector. Consequently, to obtain more insight into these transmission routes, it is important to know how long the virus remains viable outside the host. In this study we examined the survival of classical swine fever virus in faeces and urine derived from pigs intranasally inoculated with a highly or moderately virulent CSFV strain. Faeces and urine were collected between days 5 and 36 post-inoculation, and stored at 5, 12, 20, and 30 degrees C. Next, the virus titres were determined in the samples by virus titration, and a random selection of these samples was also analyzed by quantitative real-time reverse transcription polymerase chain reaction (qRRT-PCR) to determine the viral RNA decay. Survival curves were generated, and it was shown that the inactivation rate was inversely related to the storage temperature. Average half-life values were between 2 and 4 days at 5 degrees C, and between 1 and 3h at 30 degrees C. Significant differences were observed in survival between virus strains in faeces, however, not in urine. The reduction in viral RNA during the entire study period was limited. This study provided detailed information on survival of CSFV in excretions of infected pigs, which can be used to improve control measures or risk-analysis models.

  16. A study of lymphoid organs and serum proinflammatory cytokines in pigs infected with African swine fever virus genotype II.

    Science.gov (United States)

    Zakaryan, Hovakim; Cholakyans, Victorya; Simonyan, Lusine; Misakyan, Alla; Karalova, Elena; Chavushyan, Andranik; Karalyan, Zaven

    2015-06-01

    African swine fever virus (ASFV), the causative agent of one of the most important viral diseases of domestic pigs for which no vaccine is available, causes immune system disorders in infected animals. In this study, the serum levels of proinflammatory cytokines, as well as the histological and cellular constitution of lymphoid organs of pigs infected with ASFV genotype II were investigated. The results showed a high degree of lymphocyte depletion in the lymphoid organs, particularly in the spleen and lymph nodes, where ASFV infection led to a twofold decrease in the number of lymphocytes on the final day of infection. Additionally, ASFV-infected pigs had atypical forms of lymphocytes found in all lymphoid organs. In contrast to lymphocytes, the number of immature immune cells, particularly myelocytes, increased dramatically and reached a maximum on day 7 postinfection. The serum levels of TNF-α, IL-1β, IL-6, and IL-8 were evaluated. Proinflammatory cytokines showed increased levels after ASFV infection, with peak values at 7 days postinfection, and this highlights their role in the pathogenesis of ASFV. In conclusion, this study showed that ASFV genotype II, like other highly virulent strains, causes severe pathological changes in the immune system of pigs.

  17. Analysis of T lymphocyte subsets proliferating in response to infective and UV-inactivated African swine fever viruses.

    Science.gov (United States)

    Canals, A; Alonso, F; Tomillo, J; Domínguez, J

    1992-11-01

    The proliferative response to infective and UV-inactivated African swine fever virus was analyzed in cells from pigs surviving an experimental infection with attenuated virus. All the pigs showed strong dose-dependent proliferative responses to both infective and UV-inactivated virus. This response was also observed when nitrocellulose-bound solubilized virus proteins were used in the assay. Heterologous isolates also induced proliferation, however it was significantly lower than that induced by the isolate used to infect the animals. The response to infective virus was blocked equally by anti-CD4 and anti-CD8 monoclonal antibodies (mAb); the response to UV-inactivated virus was almost abolished by anti-CD4 and 60% inhibited by anti-CD8 mAb. FACS analysis of 28-day T cell lines derived from peripheral blood mononuclear cells demonstrated the progressive increase of the CD8+ subset when the cells were stimulated with infective virus, whereas the stimulation with UV-inactivated virus induced the increase of both CD4+ and CD8+ subsets. In this case, the sum of CD4+ and CD8+ percentages was higher than the total percentage of T cells, suggesting the presence of cells positive for both CD4+ and CD8+.

  18. Classical Swine Fever Virus-Rluc Replicons

    DEFF Research Database (Denmark)

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

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

  19. 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.

  20. 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.

  1. 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.

  2. 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. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

  3. 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. Copyright © 2016 Elsevier B.V. All rights reserved.

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

    International Nuclear Information System (INIS)

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

    2004-01-01

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

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

    International Nuclear Information System (INIS)

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

    2006-01-01

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

  6. 9 CFR 94.10 - Swine from regions where classical swine fever exists.

    Science.gov (United States)

    2010-01-01

    ... 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 SWINE FEVER, SWINE VESICULAR DISEASE, AND BOVINE SPONGIFORM ENCEPHALOPATHY: PROHIBITED AND RESTRICTED...

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

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

    2018-01-12

    Jan 12, 2018 ... Photo: IDRC / Bartay The challenge African swine fever (ASF) is a highly infectious hemorrhagic viral disease that wipes out entire herds of infected pigs. ASF is widespread in at least half of sub-Saharan Africa, and threatens food security due to devastating economic losses.

  8. Quantification of underlying mechanisms of classical swine fever virus transmission

    NARCIS (Netherlands)

    Weesendorp, E.

    2010-01-01

    Classical swine fever (CSF) is an exotic viral disease in most European countries. Occasionally, outbreaks occur due to re-introduction of the virus. During these outbreaks, virus transmission between herds occurs via direct contact between infected and susceptible pigs, or via indirect transmission

  9. Classical Swine Fever-An Updated Review.

    Science.gov (United States)

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

    2017-04-21

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

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

    DEFF Research Database (Denmark)

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

    2017-01-01

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

  11. swine fever virus (asfv) from natural infection in a nigerian baby

    African Journals Online (AJOL)

    A single, discrete and specific band of expected size (278bp) when measured against 200bp (base pair) DNA molecular ... er al., 2000), The virus multiplies in the cytoplasm of the infected cells. In“ nature ... The ASFV genome comprised of a linear double stranded DNA molecule which are covalently closed at both ends by ...

  12. Inhibition of IL-2R and SLA class II expression on stimulated lymphocytes by a suppressor activity found in homogenates of African swine fever virus infected cultures.

    Science.gov (United States)

    Canals, A; Domínquez, J; Tomillo, J; Babín, M; Alonso, F

    1995-01-01

    Virus free supernatants (VFS) obtained by ultracentrifugation of homogenates of African swine fever (ASF) virus infected cultures inhibited the proliferative response and the expression in peripheral blood mononuclear cells of two activation molecules, the IL-2 receptor (IL-2R) and the swine MHC class II antigens (SLA II), induced by several stimuli (lectins, PMA plus the calcium ionophore A23187 or specific antigen). This inhibition was time dependent: no effect was seen on IL-2R expression when VFS was added after 48 h, when the expression of this molecule reached its maximum. However at this time the proliferative response was still inhibited. The presence of VFS in the cultures was necessary to inhibit both the IL-2R expression and the proliferation of cells. In these conditions the addition of exogenous IL-2 to the cultures failed to restore the IL-2R expression and the proliferation shown by control stimulated cells. Furthermore, the IL-2 activity found in supernatants from cell cultures stimulated with Con A in the presence of VFS was even higher than in cultures stimulated without VFS. The inhibition observed suggests an important impairment of host immunocompetence in ASF infected swine.

  13. Course and transmission characteristics of oral low-dose infection of domestic pigs and European wild boar with a Caucasian African swine fever virus isolate.

    Science.gov (United States)

    Pietschmann, Jana; Guinat, Claire; Beer, Martin; Pronin, Valery; Tauscher, Kerstin; Petrov, Anja; Keil, Günther; Blome, Sandra

    2015-07-01

    In 2007, African swine fever virus (ASFV) was introduced into the Transcaucasian countries and Russia. Since then, it has spread alarmingly and reached the European Union. ASFV strains are highly virulent and lead to almost 100% mortality under experimental conditions. However, the possibility of dose-dependent disease courses has been discussed. For this reason, a study was undertaken to assess the risk of chronic disease and the establishment of carriers upon low-dose oronasal infection of domestic pigs and European wild boar. It was demonstrated that very low doses of ASFV are sufficient to infect especially weak or runted animals by the oronasal route. Some of these animals did not show clinical signs indicative of ASF, and they developed almost no fever. However, no changes were observed in individual animal regarding the onset, course and outcome of infection as assessed by diagnostic tests. After amplification of ASFV by these animals, pen- and stablemates became infected and developed acute lethal disease with similar characteristics in all animals. Thus, we found no indication of prolonged or chronic individual courses upon low-dose infection in either species. The scattered onset of clinical signs and pathogen detection within and among groups confirms moderate contagiosity that is strongly linked with blood contact. In conclusion, the prolonged course at the "herd level" together with the exceptionally low dose that proved to be sufficient to infect a runted wild boar could be important for disease dynamics in wild-boar populations and in backyard settings.

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

    Science.gov (United States)

    Weesendorp, Eefke; Stegeman, Arjan; Loeffen, Willie

    2009-01-01

    Classical swine fever virus (CSFV) is transmitted via secretions and excretions of infected pigs. The efficiency and speed of the transmission depends on a multitude of parameters, like quantities of virus excreted by infected pigs. This study provides quantitative data on excretion of CSFV over time from pigs infected with a highly, moderately or low virulent strain. For each strain, five individually housed pigs were infected. Virus excretion was quantified in oropharyngeal fluid, saliva, nasal fluid, lacrimal fluid, faeces, urine and skin scraping by virus titration and quantitative Real-Time Reverse Transcription Polymerase Chain Reaction (qRRT-PCR). Infectious virus was excreted in all secretions and excretions of pigs infected with the highly and moderately virulent strain, while excretion from pigs infected with the low virulent strain was mostly restricted to the oronasal route. Pigs infected with the highly virulent strain excreted significantly more virus in all their secretions and excretions over the entire infectious period than pigs infected with the moderately or low virulent strains. An exception were the pigs that developed the chronic form of infection after inoculation with the moderately virulent strain. During the entire infectious period, they excreted the largest amounts of virus via most secretions and excretions, as they excreted virus continuously and for a long duration. This study highlights the crucial role chronically infected pigs may play in the transmission of CSFV. Furthermore, it demonstrates the importance of discriminating between strains and the clinical appearance of infection when using excretion data for modelling.

  15. 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. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. 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.

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

    African Journals Online (AJOL)

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

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

    Science.gov (United States)

    Meyer, Denise; Schmeiser, Stefanie; Postel, Alexander; Becher, Paul

    2015-01-01

    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.

  19. Circoviral infections in swine

    Directory of Open Access Journals (Sweden)

    Ivetić Vojin

    2002-01-01

    Full Text Available Circoviral infections in swine have appeared only recently and they today attract the attention of large numbers of researchers all over the world. They represent a great mystery, an unknown in veterinary medicine, both in our country and in the world. The causes of these infections are circoviruses, called after the DNA which is shaped like a circle. A large number of authors today believe the PCV-2 causes two pathological entities in weaned piglets which are known as porcine multisystemic wasting syndrome (PMWS and porcine dermatitis nephropathy syndrome (PDNS. Current investigations indicate that there is a causal connection between these two syndromes. These two new diseases, which have recently spread all over the world, cause serious losses, great concern and confusion, especially when they occur simultaneously or in a sequence in the same herd, or in parallel with other pathogenes, primarily with the porcine reproductive and respiratory syndrome virus (PRRSV and the porcine parvovirus (PPV. PMWS was first described in Canada in 1991. It most often affect pigs aged 5-12 weeks. The main clinical expression, depending on the stage of progression is diarrhea, delayed development or depressed growth, stuntedness, dyspnea ictherus, eyelid swelling, and lymphadenopathy. More rarely, there are neurological symptoms. Prominent suppression of the immune system is the main characteristic of PMWS, and a wave of secondary bacterial infection is also observed. PDNS is a new disease of economic importance, which mostly affects older swine, from 5 weeks to 5 months of age. The most prominent clinical symptoms in seriously ill piglets is extensive dermatitis, mostly on the chest, abdomen, haunches and forelegs, with the appearance of purple-red swellings of different shape and size. The swine are depressive febrile, anorectic, all of which leads to stunted growth. They are inactive. Mortality is often about 15%. PDNS is a differentially diagnostically

  20. Transmission of classical swine fever virus depends on the clinical course of infection which is associated with high and low levels of virus excretion.

    Science.gov (United States)

    Weesendorp, Eefke; Backer, Jantien; Stegeman, Arjan; Loeffen, Willie

    2011-01-27

    Infection with moderately virulent strains of classical swine fever virus (CSFV) can lead to different courses of disease: either (sub)acute, resulting in death or recovery, or chronic disease. The virus excretion dynamics between these courses are quite dissimilar, but it is not known if this also results in differences in virus transmission. In this study, the excretion and transmission dynamics of the moderately virulent Paderborn strain were studied in 15 one-to-one experiments. In these experiments, a single inoculated pig was housed with a single susceptible contact pig from day 1 post-inoculation (p.i.). Each contact pig that became infected was removed and replaced by a new contact pig at day 17 p.i. and day 26 p.i. Infection of contact pigs was monitored by reverse transcription quantitative real-time PCR on oropharyngeal fluid samples. Five of the inoculated pigs developed the chronic form or died during the acute phase (high excreting pigs), while 10 pigs recovered from the infection (low excreting pigs). In the first contact period, there was no significant difference in virus excretion between the high and low excreting pigs, while in the second and third contact period, high excreting pigs excreted significantly higher quantities of virus. Over the entire study period, the reproduction ratio differed significantly between the high (143 [56.3-373]) and low excreting pigs (23.1 [11.5-45.0]). This indicates the importance of high excreting pigs in transmission of CSFV. Furthermore, this study showed the rate of CSFV infections from a contaminated environment. Copyright © 2010 Elsevier B.V. All rights reserved.

  1. 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. Published by Elsevier B.V.

  2. African swine fever virus isolate, Georgia, 2007.

    Science.gov (United States)

    Rowlands, Rebecca J; Michaud, Vincent; Heath, Livio; Hutchings, Geoff; Oura, Chris; Vosloo, Wilna; Dwarka, Rahana; Onashvili, Tinatin; Albina, Emmanuel; Dixon, Linda K

    2008-12-01

    African swine fever (ASF) is widespread in Africa but is rarely introduced to other continents. In June 2007, ASF was confirmed in the Caucasus region of Georgia, and it has since spread to neighboring countries. DNA fragments amplified from the genome of the isolates from domestic pigs in Georgia in 2007 were sequenced and compared with other ASF virus (ASFV) isolates to establish the genotype of the virus. Sequences were obtained from 4 genome regions, including part of the gene B646L that encodes the p72 capsid protein, the complete E183L and CP204L genes, which encode the p54 and p30 proteins and the variable region of the B602L gene. Analysis of these sequences indicated that the Georgia 2007 isolate is closely related to isolates belonging to genotype II, which is circulating in Mozambique, Madagascar, and Zambia. One possibility for the spread of disease to Georgia is that pigs were fed ASFV-contaminated pork brought in on ships and, subsequently, the disease was disseminated throughout the region.

  3. The effectiveness of classical swine fever surveillance programmes in The Netherlands

    NARCIS (Netherlands)

    Klinkenberg, D.; Nielen, M.; Mourits, M.C.M.; Jong, de M.C.M.

    2005-01-01

    Consequences of classical swine fever (CSF) epidemics depend on the control measures, but also on the number of infected herds at the end of the high-risk period (HRP). Surveillance programmes aim to keep this number as low as possible, so the effectiveness of surveillance programmes can be measured

  4. [Classical swine fever in wild boars in Switzerland].

    Science.gov (United States)

    Hofmann, M A; Thür, B; Vanzetti, T; Schleiss, W; Schmidt, J; Griot, C

    1999-01-01

    In May 1998, wild boars with classical swine fever (CSF) symptoms were detected in the southern part (Canton Ticino) of Switzerland. CSF virus was isolated from the submitted samples and RT-PCR followed by direct nucleotide sequencing of the 5' non-translated region showed that this virus was identical to the isolate previously recognized in wild boars from the area of Varese (Italy). In most animals, antibodies to CSF virus were detected as well. An immediate measurement was taken by limiting the movement of pigs and identifying both risk and surveillance zones. In order not to disturb potentially infected wild boars within their habitat a complete hunting prohibition for 2 months was enforced. The different possibilities of the control of CSF outbreaks in wild boars are discussed.

  5. Seroprevalence of African Swine Fever in Senegal, 2006

    Science.gov (United States)

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

    2011-01-01

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

  6. 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. Functional analysis of replication determinantsin classical swine fever virus

    DEFF Research Database (Denmark)

    Hadsbjerg, Johanne

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

  8. African swine fever virus uses macropinocytosis to enter host cells.

    Directory of Open Access Journals (Sweden)

    Elena G Sánchez

    Full Text Available African swine fever (ASF is caused by a large and highly pathogenic DNA virus, African swine fever virus (ASFV, which provokes severe economic losses and expansion threats. Presently, no specific protection or vaccine against ASF is available, despite the high hazard that the continued occurrence of the disease in sub-Saharan Africa, the recent outbreak in the Caucasus in 2007, and the potential dissemination to neighboring countries, represents. Although virus entry is a remarkable target for the development of protection tools, knowledge of the ASFV entry mechanism is still very limited. Whereas early studies have proposed that the virus enters cells through receptor-mediated endocytosis, the specific mechanism used by ASFV remains uncertain. Here we used the ASFV virulent isolate Ba71, adapted to grow in Vero cells (Ba71V, and the virulent strain E70 to demonstrate that entry and internalization of ASFV includes most of the features of macropinocytosis. By a combination of optical and electron microscopy, we show that the virus causes cytoplasm membrane perturbation, blebbing and ruffles. We have also found that internalization of the virions depends on actin reorganization, activity of Na(+/H(+ exchangers, and signaling events typical of the macropinocytic mechanism of endocytosis. The entry of virus into cells appears to directly stimulate dextran uptake, actin polarization and EGFR, PI3K-Akt, Pak1 and Rac1 activation. Inhibition of these key regulators of macropinocytosis, as well as treatment with the drug EIPA, results in a considerable decrease in ASFV entry and infection. In conclusion, this study identifies for the first time the whole pathway for ASFV entry, including the key cellular factors required for the uptake of the virus and the cell signaling involved.

  9. 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...... described in detail previously. We found that oronasal infection with 10(4.7) TCID50 produced mortality in three out of five pigs after 29-31 days, and severe clinical symptoms in one out of five pigs, while one out of five pigs exhibited no clinical symptoms. At this infection dose, pigs had viral RNA...... viral RNA in serum for more than 30 days, and exhibited only mild clinical symptoms. We observed an excellent correlation between clinical symptoms and viral RNA loads in serum, while serum antibody levels were low. Clinically affected pigs had up to 1000-fold higher serum viral RNA loads than did pigs...

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

    NARCIS (Netherlands)

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

    2012-01-01

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

  11. 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

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    Modulation of translation initiation efficiency on classical swine fever virus (CSFV) RNA can be achieved by targeted mutations within the internal ribosome entry site (IRES). In this study, cDNAs corresponding to the wild type (wt) or mutant forms of the IRES of CSFV strain Paderborn were...

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

    DEFF Research Database (Denmark)

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

    Modulation of translation initiation efficiency on classical swine fever virus (CSFV) RNA can be achieved by targeted mutations within the internal ribosome entry site (IRES). In this study, the nucleotides 47 to 427, including the IRES region of the wt CSFV strain Paderborn, were amplified...

  14. African Swine Fever control in Ibadan, Nigeria: problems, needs and ...

    African Journals Online (AJOL)

    African swine fever (ASF) is a widely discussed disease in Ibadan, Nigeria, where high mortality losses occurred in outbreaks in the city between 2001-2006. To study the level to which ASF containment technologies were adopted and factors associated with adoption behavior, a sample of 60 pig farmers was selected from ...

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

    DEFF Research Database (Denmark)

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

    2016-01-01

    resulted in marginal improvements to the control of the epidemics. However, adding testing of dead animals in the protection and surveillance zones was predicted to be the optimal control scenario for an ASF epidemic in industrialized swine populations without contact to wild boar. This optimal scenario...

  16. 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 Eur...

  17. 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.

  18. Regulation of host translational machinery by African swine fever virus.

    Directory of Open Access Journals (Sweden)

    Alfredo Castelló

    2009-08-01

    Full Text Available African swine fever virus (ASFV, like other complex DNA viruses, deploys a variety of strategies to evade the host's defence systems, such as inflammatory and immune responses and cell death. Here, we analyse the modifications in the translational machinery induced by ASFV. During ASFV infection, eIF4G and eIF4E are phosphorylated (Ser1108 and Ser209, respectively, whereas 4E-BP1 is hyperphosphorylated at early times post infection and hypophosphorylated after 18 h. Indeed, a potent increase in eIF4F assembly is observed in ASFV-infected cells, which is prevented by rapamycin treatment. Phosphorylation of eIF4E, eIF4GI and 4E-BP1 is important to enhance viral protein production, but is not essential for ASFV infection as observed in rapamycin- or CGP57380-treated cells. Nevertheless, eIF4F components are indispensable for ASFV protein synthesis and virus spread, since eIF4E or eIF4G depletion in COS-7 or Vero cells strongly prevents accumulation of viral proteins and decreases virus titre. In addition, eIF4F is not only activated but also redistributed within the viral factories at early times of infection, while eIF4G and eIF4E are surrounding these areas at late times. In fact, other components of translational machinery such as eIF2alpha, eIF3b, eIF4E, eEF2 and ribosomal P protein are enriched in areas surrounding ASFV factories. Notably, the mitochondrial network is polarized in ASFV-infected cells co-localizing with ribosomes. Thus, translation and ATP synthesis seem to be coupled and compartmentalized at the periphery of viral factories. At later times after ASFV infection, polyadenylated mRNAs disappear from the cytoplasm of Vero cells, except within the viral factories. The distribution of these pools of mRNAs is similar to the localization of viral late mRNAs. Therefore, degradation of cellular polyadenylated mRNAs and recruitment of the translation machinery to viral factories may contribute to the inhibition of host protein synthesis

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

    Science.gov (United States)

    Herrera-Ibatá, Diana María; Martínez-López, Beatriz; Quijada, Darla; Burton, Kenneth; Mur, Lina

    2017-01-01

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

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

    DEFF Research Database (Denmark)

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

    2001-01-01

    mirroring the delayed time point of infection. There was thus some protection against clinical illness by both marker vaccines, but not a solid protection against infection and virus shedding. The efficacy of the vaccine was best if used 3 weeks before challenge and a clear correlation between time inter......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...

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

    NARCIS (Netherlands)

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

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

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

    DEFF Research Database (Denmark)

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

    Classical Swine Fever is a highly contagious disease of pigs caused by Classical Swine Fever Virus (CSFV), a member of the pestivirus genus within the family Flaviviridae. The E2 glycoprotein of CSFV has been shown to be an important factor for the virulence of the virus. In a recent study, we have...

  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. © 2015 The Author(s).

  4. 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.

  5. 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...

  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

    2016-10-22

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

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

    Directory of Open Access Journals (Sweden)

    Jolene Carlson

    2016-10-01

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

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

    Science.gov (United States)

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

    2015-03-01

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

  9. Rope-based oral fluid sampling for early detection of classical swine fever in domestic pigs at group level.

    Science.gov (United States)

    Dietze, Klaas; Tucakov, Anna; Engel, Tatjana; Wirtz, Sabine; Depner, Klaus; Globig, Anja; Kammerer, Robert; Mouchantat, Susan

    2017-01-05

    Non-invasive sampling techniques based on the analysis of oral fluid specimen have gained substantial importance in the field of swine herd management. Methodological advances have a focus on endemic viral diseases in commercial pig production. More recently, these approaches have been adapted to non-invasive sampling of wild boar for transboundary animal disease detection for which these effective population level sampling methods have not been available. In this study, a rope-in-a-bait based oral fluid sampling technique was tested to detect classical swine fever virus nucleic acid shedding from experimentally infected domestic pigs. Separated in two groups treated identically, the course of the infection was slightly differing in terms of onset of the clinical signs and levels of viral ribonucleic acid detection in the blood and oral fluid. The technique was capable of detecting classical swine fever virus nucleic acid as of day 7 post infection coinciding with the first detection in conventional oropharyngeal swab samples from some individual animals. Except for day 7 post infection in the "slower onset group", the chances of classical swine fever virus nucleic acid detection in ropes were identical or higher as compared to the individual sampling. With the provided evidence, non-invasive oral fluid sampling at group level can be considered as additional cost-effective detection tool in classical swine fever prevention and control strategies. The proposed methodology is of particular use in production systems with reduced access to veterinary services such as backyard or scavenging pig production where it can be integrated in feeding or baiting practices.

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

    Science.gov (United States)

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

  11. 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

  12. Genetic typing of recent classical swine fever isolates from India.

    Science.gov (United States)

    Patil, S S; Hemadri, D; Shankar, B P; Raghavendra, A G; Veeresh, H; Sindhoora, B; Chandan, S; Sreekala, K; Gajendragad, M R; Prabhudas, K

    2010-03-24

    Seventeen classical swine fever virus (CSFV) isolates recovered during the period of 3 years (2006-2008) from India were subjected to nucleotide sequencing in the 5' untranslated region (UTR). For genetic typing, 150 nucleotides within this region were used. For better epizootiological understanding, 39 nucleotide sequences of the above region, including 13 Indian CSFV sequences, available either in the Genbank or published literature were also included in the study. Based on the phylogenetic analysis, the Indian isolates could be grouped in to two subgroups, viz., 1.1 and 2.2. The study also revealed predominance of subgroup 1.1 and involvement of viruses of more than one subgroup in an outbreak. Copyright 2009 Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

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

    2014-01-01

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

  14. 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.

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

    Science.gov (United States)

    Hone, J; Pech, R; Yip, P

    1992-04-01

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

  16. African swine fever virus introduction into the EU in 2014: Experience of Latvia.

    Science.gov (United States)

    Oļševskis, Edvīns; Guberti, Vittorio; Seržants, Mārtiņš; Westergaard, Jørgen; Gallardo, Carmina; Rodze, Ieva; Depner, Klaus

    2016-04-01

    African swine fever (ASF) virus was introduced in Latvia in June 2014. Thirty-two outbreaks in domestic pigs and 217 cases in wild boar were notified in 2014. Twenty-eight outbreaks (87.5%) were primary outbreaks. The contagiosity within pig herds was low. Failure to use simple biosecurity measures to reduce the chance of virus introduction, for example by inadvertent feeding of locally produced virus contaminated fodder were the main causes for the outbreaks in backyard holdings. The infection in wild boar survived locally in two different areas with a low prevalence and a slow spread. The persistence of the infection in wild boar within an area was most probably linked to wild boar scavenging the carcasses of infected wild boar. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Redistribution of Endosomal Membranes to the African Swine Fever Virus Replication Site

    Directory of Open Access Journals (Sweden)

    Miguel Ángel Cuesta-Geijo

    2017-06-01

    Full Text Available African swine fever virus (ASFV infection causes endosomal reorganization. Here, we show that the virus causes endosomal congregation close to the nucleus as the infection progresses, which is necessary to build a compact viral replication organelle. ASFV enters the cell by the endosomal pathway and reaches multivesicular late endosomes. Upon uncoating and fusion, the virus should exit to the cytosol to start replication. ASFV remodels endosomal traffic and redistributes endosomal membranes to the viral replication site. Virus replication also depends on endosomal membrane phosphoinositides (PtdIns synthesized by PIKfyve. Endosomes could act as platforms providing membranes and PtdIns, necessary for ASFV replication. Our study has revealed that ASFV reorganizes endosome dynamics, in order to ensure a productive infection.

  18. A five-year survey of African swine fever outbreaks in Plateau State ...

    African Journals Online (AJOL)

    Reported here is a five-year account of outbreaks of African swine fever (ASF) in Plateau state, which devastated swine production and almost threw the whole pig induatry of the state in total disarray. Although veterinary authorities from 15 local government areas (LGA) of the state kreported the lsuspicion of the ldiseas, ...

  19. Scarlet Fever: A Group A Streptococcal Infection

    Science.gov (United States)

    ... Submit What's this? Submit Button Past Emails Scarlet Fever: A Group A Streptococcal Infection Language: English (US) ... and 15 years old. People Can Spread Scarlet Fever Germs to Others Group A strep bacteria can ...

  20. [Possibilities and limitations in veterinary vaccine development using the example of classical swine fever].

    Science.gov (United States)

    Blome, Sandra; Gabriel, Claudia; Beer, Martin

    2013-01-01

    The use of vaccines is still one of the most effective tools to control infectious diseases. Up to now, conventional vaccines are employed in the majority of cases. Drawbacks of these established vaccines include the lack of differentiability of infected from vaccinated animals (DIVA or marker strategy), limitations in the efficacy spectrum, and constraints and restrictions in production. For this reason, new vaccines, which do not show these disadvantages, are under development, especially for notifiable diseases such as classical swine fever (CSF). In principle, the following modern vaccine types can be differentiated: recombinant attenuated vaccines, recombinant inactivated vaccines or subunit vaccines, vector vaccines, and DNA/ RNA vaccines. During the last years, especially attenuated deletion vaccines or chimeric constructs have shown potential. Under field conditions, all marker vaccines have to be accompanied by a potent test system. Particularly this point often shows weaknesses. Alternative vaccine candidates are so far only prototypes and licensing is only a medium term possibility. Moreover, most of these vaccines are genetically engineered and can be problematic in terms of licensing and the public's acceptance. In conclusion, conventional vaccines still present the standard, especially in terms of efficacy. Yet, only vaccines with DIVA properties are feasible for the control of CSF. Thus, development and assessment of alternative vaccines is of paramount importance. The present overview summarizes concepts and vaccine types using the example of classical swine fever. It also recapitulates their advantages and disadvantages as well as their limitations.

  1. Prevalence of African swine fever virus in apparently healthy domestic pigs in Uganda.

    Science.gov (United States)

    Atuhaire, David Kalenzi; Afayoa, Mathias; Ochwo, Sylvester; Mwesigwa, Savannah; Mwiine, Frank Norbert; Okuni, Julius Boniface; Olaho-Mukani, William; Ojok, Lonzy

    2013-12-26

    African swine fever (ASF) is a contagious viral disease which can cause up to 100% mortality among domestic pigs leading to serious socio-economic impact on people's livelihoods. ASF is endemic in Uganda and there is paucity of information on the epidemiology of the disease. The major aim of this study was to determine the seroprevalence and prevalence of African swine fever virus (ASFV) in apparently healthy slaughter pigs at Wambizi slaughterhouse in Kampala city, Uganda. We also estimated the presence of ASFV antibodies and circulating viral antigens in pigs from selected districts of Uganda during targeted surveillance. We analysed 540 and 181 blood samples collected from slaughter pigs and pigs from targeted surveillance districts respectively. The prevalence of ASFV in slaughter pigs was 52.96% (95% CI, 48.75-57.14) and 11.5% (95% CI, 9.06-14.45) by ELISA and PCR respectively. In surveillance districts, the proportion of ASFV positive pigs was 53.59% (95% CI, 46.33-60.71) and 0.55% (95% CI, 0.1-3.06) by ELISA and PCR respectively. The study has found out a high seroprevalence of ASFV antibodies in apparently healthy slaughter pigs and also a high proportion of ASFV antibody seropositive pigs in surveyed districts in Uganda indicating exposure to ASFV. However, there was a lower prevalence of ASFV infection implying that there could be low virulent strains of ASFV circulating in domestic pigs in Uganda which requires further investigation.

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

    Directory of Open Access Journals (Sweden)

    Sumit Chowdhury

    2016-12-01

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

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

    Directory of Open Access Journals (Sweden)

    Vienna R. Brown

    2018-02-01

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

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

    Science.gov (United States)

    Brown, Vienna R.; Bevins, Sarah N.

    2018-01-01

    African swine fever (ASF) is caused by African swine fever virus (ASFV), which can cause substantial morbidity and mortality events in swine. The virus can be transmitted via direct and indirect contacts with infected swine, their products, or competent vector species, especially Ornithodoros ticks. Africa and much of Eastern Europe are endemic for ASF; a viral introduction to countries that are currently ASF free could have severe economic consequences due to the loss of production from infected animals and the trade restrictions that would likely be imposed as a result of an outbreak. We identified vulnerabilities that could lead to ASFV introduction or persistence in the United States or other ASF-free regions. Both legal and illegal movements of live animals, as well as the importation of animal products, byproducts, and animal feed, pose a risk of virus introduction. Each route is described, and current regulations designed to prevent ASFV and other pathogens from entering the United States are outlined. Furthermore, existing ASFV research gaps are highlighted. Laboratory experiments to evaluate multiple species of Ornithodoros ticks that have yet to be characterized would be useful to understand vector competence, host preferences, and distribution of competent soft tick vectors in relation to high pig production areas as well as regions with high feral swine (wild boar or similar) densities. Knowledge relative to antigenic viral proteins that contribute to host response and determination of immune mechanisms that lead to protection are foundational in the quest for a vaccine. Finally, sampling of illegally imported and confiscated wild suid products for ASFV could shed light on the types of products being imported and provide a more informed perspective relative to the risk of ASFV importation. PMID:29468165

  5. 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. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. 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. © 2011 Blackwell Verlag GmbH.

  7. 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...

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

    Science.gov (United States)

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

    2015-05-13

    African swine fever (ASF) is a fatal, haemorrhagic disease of domestic pigs, that poses a serious threat to pig farmers and is currently endemic in domestic pigs in most of sub-Saharan Africa. To obtain insight into the factors related to ASF outbreaks at the farm-level, a longitudinal study was performed in one of the major pig producing areas in central Uganda. Potential risk factors associated with outbreaks of ASF were investigated including the possible presence of apparently healthy ASF-virus (ASFV) infected pigs, which could act as long-term carriers of the virus. Blood and serum were sampled from 715 pigs (241 farms) and 649 pigs (233 farms) to investigate presence of ASFV and antibodies, during the periods of June-October 2010 and March-June 2011, respectively. To determine the potential contribution of different risks to ASF spread, a questionnaire-based survey was administered to farmers to assess the association between ASF outbreaks during the study period and the risk factors. Fifty-one (21 %) and 13 (5.6 %) farms reported an ASF outbreak on their farms in the previous one to two years and during the study period, respectively. The incidence rate for ASF prior to the study period was estimated at 14.1 per 100 pig farm-years and 5.6 per 100 pig farm-years during the study. Three pigs tested positive for ASFV using real-time PCR, but none tested positive for ASFV specific antibodies using two different commercial ELISA tests. There was no evidence for existence of pigs that were long-term carriers for the virus based on the analysis of blood and serum as there were no seropositive pigs and the only three ASFV DNA positive pigs were acutely infected and were linked to outbreaks reported by farmers during the study. Potential ASF risk factors were present on both small and medium-scale pig farms, although small scale farms exhibited a higher proportion with multiple potential risk factors (like borrowing boars for sows mating, buying replacement from

  9. 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

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

    DEFF Research Database (Denmark)

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

    2003-01-01

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

  11. 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...

  12. African swine fever: A re-emerging viral disease threatening the global pig industry.

    Science.gov (United States)

    Sánchez-Cordón, P J; Montoya, M; Reis, A L; Dixon, L K

    2018-03-01

    African swine fever (ASF) recently has spread beyond sub-Saharan Africa to the Trans-Caucasus region, parts of the Russian Federation and Eastern Europe. In this new epidemiological scenario, the disease has similarities, but also important differences, compared to the situation in Africa, including the substantial involvement of wild boar. A better understanding of this new situation will enable better control and prevent further spread of disease. In this article, these different scenarios are compared, and recent information on the pathogenesis of ASF virus strains, the immune response to infection and prospects for developing vaccines is presented. Knowledge gaps and the prospects for future control are discussed. Copyright © 2018 The Pirbright Institute. Published by Elsevier Ltd.. All rights reserved.

  13. 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. Copyright © 2013 Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

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

  15. 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...... demonstrated that it remains a particular challenge to provide a competent diagnostic tool box for low virulent strains of CSFV, e.g. CSFV-Glentorf. Acknowledgements: The authors wish to thank the EU Reference laboratory for Classical Swine Fever, TIHO, Hannover, for kindly supplying the CSFV-Romania, the CSFV...

  16. Phylogenetic characterization of classical swine fever viruses isolated in Korea between 1988 and 2003.

    Science.gov (United States)

    Cha, Sang-Ho; Choi, Eun-Jin; Park, Jong-Hyun; Yoon, So-Ra; Kwon, Jun-Hun; Yoon, Kyoung-Jin; Song, Jae-Young

    2007-06-01

    Twenty-four isolates of classical swine fever (CSF) virus which were obtained from CSF outbreaks during 1988 and 2003 in the Republic of Korea were genetically characterized for partial E2 gene (190 nucleotides) and compared with CSF viruses reported by other countries. Phylogenetic analyses classified Korean field isolates between1988 and 1999 into subgroup 3.2, forming an independent clade distinct from CSF viruses identified in other countries. In contrast, the viruses isolated during 2002-2003 CSF epidemics were classified into a different subgroup (2.1). The 2.1 viruses showed a close genetic relationship (92.1-100% nucleotide similarity) with CSF viruses reported from China and Taiwan in 1998-2001. As no evidence of CSF virus infection was detected in the wild boar (Sus scrofa coreanus) population that inhabits Korea, the results of molecular characterization strongly suggest that CSF epidemic outbreaks in Korean swine populations during 2002-2003 were attributed to the introduction of a new strain or strains, likely from neighboring countries.

  17. 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...

  18. 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...

  19. Fever

    Science.gov (United States)

    ... ear infections , sinus infections , mononucleosis , bronchitis , pneumonia , and tuberculosis Urinary tract infections Viral gastroenteritis and bacterial gastroenteritis Children may have a low-grade fever for 1 ...

  20. 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

  1. 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. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. In vitro inhibition of African swine fever virus-topoisomerase II disrupts viral replication.

    Science.gov (United States)

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

    2016-10-01

    African swine fever virus (ASFV) is the etiological agent of a highly-contagious and fatal disease of domestic pigs, leading to serious socio-economic impact in affected countries. To date, neither a vaccine nor a selective anti-viral drug are available for prevention or treatment of African swine fever (ASF), emphasizing the need for more detailed studies at the role of ASFV proteins involved in viral DNA replication and transcription. Notably, ASFV encodes for a functional type II topoisomerase (ASFV-Topo II) and we recently showed that several fluoroquinolones (bacterial DNA topoisomerase inhibitors) fully abrogate ASFV replication in vitro. Here, we report that ASFV-Topo II gene is actively transcribed throughout infection, with transcripts being detected as early as 2 hpi and reaching a maximum peak concentration around 16 hpi, when viral DNA synthesis, transcription and translation are more active. siRNA knockdown experiments showed that ASFV-Topo II plays a critical role in viral DNA replication and gene expression, with transfected cells presenting lower viral transcripts (up to 89% decrease) and reduced cytopathic effect (-66%) when compared to the control group. Further, a significant decrease in the number of both infected cells (75.5%) and viral factories per cell and in virus yields (up to 99.7%, 2.5 log) was found only in cells transfected with siRNA targeting ASFV-Topo II. We also demonstrate that a short exposure to enrofloxacin during the late phase of infection (from 15 to 1 hpi) induces fragmentation of viral genomes, whereas no viral genomes were detected when enrofloxacin was added from the early phase of infection (from 2 to 16 hpi), suggesting that fluoroquinolones are ASFV-Topo II poisons. Altogether, our results demonstrate that ASFV-Topo II enzyme has an essential role during viral genome replication and transcription, emphasizing the idea that this enzyme can be a potential target for drug and vaccine development against ASF

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

    African Journals Online (AJOL)

    A study was carried out to evaluate the socio-economic impact of African swine fever (ASF) and associated epidemiological factors following the 2011 outbreak in Isoka district of Zambia. One hundred and twenty small holder farmers were interviewed using a structured questionnaire to collect information on the ...

  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. 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...

  6. The potential of antiviral agents to control classical swine fever: A modelling study.

    NARCIS (Netherlands)

    Backer, J.A.; Vrancken, R.; Neyts, J.; Goris, N.

    2013-01-01

    Classical swine fever (CSF) represents a continuous threat to pig populations that are free of disease without vaccination. When CSF virus is introduced, the minimal control strategy imposed by the EU is often insufficient to mitigate the epidemic. Additional measures such as preemptive culling

  7. Inactivation of classical swine fever virus in porcine casing preserved in salt.

    Science.gov (United States)

    Wijnker, J J; Depner, K R; Berends, B R

    2008-12-10

    Pig intestines used for the production of natural sausage casings may carry classical swine fever (CSF) virus. Feeding pigs with human food waste that contains pig casings may then spread the virus to CSF-free animals. Casings derived from a pig experimentally infected with CSF by dosing with 10(6) tissue culture infectious doses (TCID50) of the highly virulent CSF virus strain "Koslov", were treated with phosphate supplemented or citrate supplemented NaCl, instead of with NaCl alone, which is the standard preservation treatment for casings. Treated casings were stored for 30 days at either 4 degrees C or 20 degrees C. After storage the casings were fed to 16 susceptible pigs. CSF infection was confirmed in the four animals that had been fed casings treated with citrate supplemented salt and stored at 4 degrees C. All other animals remained healthy. It is therefore possible to avoid the inadvertent spread of CSF virus via porcine sausage casings by treating casings with phosphate supplemented salt and storing them for 30 days at temperatures over 4 degrees C.

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

    Science.gov (United States)

    Lyra, T M P

    2006-04-01

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

  9. Enhancing expression of the classical swine fever virus glycoprotein E2 in yeast and its application to a blocking ELISA.

    Science.gov (United States)

    Cheng, Chih-Yuan; Wu, Ching-Wei; Lin, Guang-Jan; Lee, Wei-Cheng; Chien, Maw-Sheng; Huang, Chienjin

    2014-03-20

    Classical swine fever virus (CSFV) infection is a severe swine disease, often causing large economic losses. A Pichia pastoris yeast-expressed CSFV glycoprotein E2 (yE2) has been shown to induce a protective immune response against the virus. To improve the expression level of yE2, the first codon of E2 gene, Arg (CGG), which is the least used in P. pastoris, was optimized to the most favorite codon AGA. The yield of E2 protein was remarkably increased in the codon optimized strain (N342). Three truncated E2 subunits encoding the N-terminal 330 (N330), 301 (N301), and 190 (N190) residues, respectively, were also constructed. The immunogenicity of each recombinant E2 subunits was confirmed by immunization of pigs, and all immunized groups demonstrated high neutralizing antibody titers after boost immunization, which lasted for a long period of time. In addition, a monoclonal antibody (MAb), 1B6, specific to yE2, was generated and shown to recognize CSFV-infected cells. A panel of swine sera were tested by peroxidase-conjugated MAb 1B6-based blocking enzyme-linked immunosorbent assay (ELISA) using N330 as coated antigen, and the assay demonstrated high sensitivity and specificity. The recombinant yE2 subunits may provide potential subunit vaccine candidates and useful diagnostic reagents for CSFV with easy manipulation and low cost. Copyright © 2014 Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

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

    2012-01-16

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

  11. 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 (

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

    Directory of Open Access Journals (Sweden)

    Woźniakowski Grzegorz

    2016-06-01

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

  13. Evolution of African swine fever virus genes related to evasion of host immune response.

    Science.gov (United States)

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

    2016-09-25

    African swine fever (ASF) is a notifiable and one of the most complex and devastating infectious disease of pigs, wild boars and other representatives of Suidae family. African swine fever virus (ASFV) developed various molecular mechanisms to evade host immune response including alteration of interferon production by multigene family protein (MGF505-2R), inhibition of NF-κB and nuclear activating factor in T-cells by the A238L protein, or modulation of host defense by CD2v lectin-like protein encoded by EP402R and EP153R genes. The current situation concerning ASF in Poland seems to be stable in comparison to other eastern European countries but up-to-date in total 106 ASF cases in wild boar and 5 outbreaks in pigs were identified. The presented study aimed to reveal and summarize the genetic variability of genes related to inhibition or modulation of infected host response among 67 field ASF isolates collected from wild boar and pigs. The nucleotide sequences derived from the analysed A238L and EP153R regions showed 100% identity. However, minor but remarkable genetic diversity was found within EP402R and MGF505-2R genes suggesting slow molecular evolution of circulating ASFV isolates and the important role of this gene in modulation of interferon I production and hemadsorption phenomenon. The obtained nucleotide sequences of Polish ASFV isolates were closely related to Georgia 2007/1 and Odintsovo 02/14 isolates suggesting their common Caucasian origin. In the case of EP402R and partially in MGF505-2R gene the identified genetic variability was related to spatio-temporal occurrence of particular cases and outbreaks what may facilitate evolution tracing of ASFV isolates. This is the first report indicating identification of genetic variability within the genes related to evasion of host immune system which may be used to trace the direction of ASFV isolates molecular evolution. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. 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.

  15. Epidemiology and control of an outbreak of classical swine fever in wild boar in Switzerland.

    Science.gov (United States)

    Schnyder, M; Stärk, K D C; Vanzetti, T; Salman, M D; Thor, B; Schleiss, W; Griot, C

    2002-01-26

    An outbreak of classical swine fever in wild boar in the southern part of Switzerland (Canton of Ticino) was investigated after the implementation of control measures in a defined infected area (the risk zone), and in a surrounding surveillance zone (the non-risk zone). After the disease had been detected, hunting was not allowed in the risk zone for over six months, during which the disease was left to run its course, but hunting was continued in the non-risk zone for one month. After seven months, a hunting strategy targeted at young animals was implemented in both zones. Between May 1998 and January 2000,1294 wild boar were shot or found dead, and diagnostic and biological data were collected and analysed. Only one animal from the non-risk zone was found to be seropositive for antibodies to the virus, whereas 179 of 528 wild boar from the risk zone were virus positive and 162 were seropositive. The proportion of virus-positive animals decreased from 62.7 per cent to zero over one year. During the first hunting season, seropositive animals were found in all age groups, but 12 months later only animals more than one year old had antibodies against the virus.

  16. [Descriptive summary of the classical swine fever control in wild boar in Germany since 2005].

    Science.gov (United States)

    Staubach, Christoph; Höreth-Böntgen, Detlef; Blome, Sandra; Fröhlich, Andreas; Blicke, Julia; Jahn, Birgit; Teuffert, Jürgen; Kramers, Matthias

    2013-01-01

    Classical swine fever (CSF) in wild boar repeatedly appeared in different federal states of the Federal Republic of Germany since 1995, from which it has been successfully eradicated sometimes fast, sometimes in a more time taking way using oral immunization as a main element of control. Since 2005 the cases focused solely on North Rhine-Westphalia and Rhineland-Palatinate. In the present study, therefore, the situation of CSF in wild boar has been closely investigated concerning the period 2005 to 2012 in these two regions. It is noteworthy that in this period two different variants of the virus subtype 2.3 occurred in two regionally defined areas of the "Eifel" and "Westerwald" as well as in the "Pfalz". The two Federal States have undertaken extensive oral vaccination campaigns and surveillance activities, which enabled an assessment of the existing virus prevalence and serological prevalence in the different regions. After an initial high serological prevalence, caused probably by interaction of infection and vaccination, the serological levels stabilized seasonally adjusted in a range from 50 to 60% in almost all areas. The vaccination campaigns have been maintained by both Federal States over a period of at least 2.5 years after virus has been detected for the last time. In consequence Germany as a whole has been recognized for the first time to be officially free from CSF in wild boar. By genotyping of virus isolates it has been demonstrated that the virus changed over time and played a role in the outbreak area "Westerwald".

  17. Genetic and virulence characterization of classical swine fever viruses isolated in Mongolia from 2007 to 2015.

    Science.gov (United States)

    Enkhbold, Bazarragchaa; Shatar, Munkhduuren; Wakamori, Shiho; Tamura, Tomokazu; Hiono, Takahiro; Matsuno, Keita; Okamatsu, Masatoshi; Umemura, Takashi; Damdinjav, Batchuluun; Sakoda, Yoshihiro

    2017-06-01

    Classical swine fever (CSF), a highly contagious viral disease affecting domestic and wild pigs in many developing countries, is now considered endemic in Mongolia, with 14 recent outbreaks in 2007, 2008, 2011, 2012, 2014, and 2015. For the first time, CSF viruses isolated from these 14 outbreaks were analyzed to assess their molecular epidemiology and pathogenicity in pigs. Based on the nucleotide sequences of their 5'-untranslated region, isolates were phylogenetically classified as either sub-genotypes 2.1b or 2.2, and the 2014 and 2015 isolates, which were classified as 2.1b, were closely related to isolates from China and Korea. In addition, at least three different viruses classified as 2.1b circulated in Mongolia. Experimental infection of the representative isolate in 2014 demonstrated moderate pathogenicity in 4-week-old pigs, with relatively mild clinical signs. Understanding the diversity of circulating CSF viruses gleans insight into disease dynamics and evolution, and may inform the design of effective CSF control strategies in Mongolia.

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

    Science.gov (United States)

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

    2016-08-17

    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. To produce pigs with antiviral protection against CSFV, transgenic pigs expressing human MxA were generated by nuclear transplantation. Cells from three MxA transgenic piglets were used to investigate in vitro antiviral activity of MxA aganist CSFV, and the results of in vitro indirect immunofluorescence assays, virus titration and real-time PCR indicated that the MxA transgenic pig has an antiviral capacity against CSFV. Transgene with human MxA on pigs is feasible. High levels of MxA expression do inhibit CSFV in vitro at early time points post-infection at 60-96dpi.

  19. 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. British Veterinary Association.

  20. The potential of antiviral agents to control classical swine fever: a modelling study.

    Science.gov (United States)

    Backer, Jantien A; Vrancken, Robert; Neyts, Johan; Goris, Nesya

    2013-09-01

    Classical swine fever (CSF) represents a continuous threat to pig populations that are free of disease without vaccination. When CSF virus is introduced, the minimal control strategy imposed by the EU is often insufficient to mitigate the epidemic. Additional measures such as preemptive culling encounter ethical objections, whereas emergency vaccination leads to prolonged export restrictions. Antiviral agents, however, provide instantaneous protection without inducing an antibody response. The use of antiviral agents to contain CSF epidemics is studied with a model describing within- and between-herd virus transmission. Epidemics are simulated in a densely populated livestock area in The Netherlands, with farms of varying sizes and pig types (finishers, piglets and sows). Our results show that vaccination and/or antiviral treatment in a 2 km radius around an infected herd is more effective than preemptive culling in a 1 km radius. However, the instantaneous but temporary protection provided by antiviral treatment is slightly less effective than the delayed but long-lasting protection offered by vaccination. Therefore, the most effective control strategy is to vaccinate animals when allowed (finishers and piglets) and to treat with antiviral agents when vaccination is prohibited (sows). As independent control measure, antiviral treatment in a 1 km radius presents an elevated risk of epidemics running out of control. A 2 km control radius largely eliminates this risk. Copyright © 2013 Elsevier B.V. All rights reserved.

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    Classical swine fever virus (CSFV) is the etiological agent of the severe porcine disease, classical swine fever. Unraveling the molecular determinants of efficient replication is crucial for gaining improved knowledge of the pathogenic features of this virus. Monitoring the replication competence...... of the CSFV genome within cells can be achieved using autonomously replicating constructs (replicons) containing a reporter gene that expresses a readily quantifiable enzyme. Here, a newly implemented cloning technique was applied to genome modification of the fulllength CSFV cDNA previously inserted...... 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...

  2. Genomic Analysis of Highly Virulent Georgia 2007/1 Isolate of African Swine Fever Virus

    Science.gov (United States)

    Chapman, David A.G.; Darby, Alistair C.; Da Silva, Melissa; Upton, Chris; Radford, Alan D.

    2011-01-01

    African swine fever is widespread in Africa but has occasionally been introduced into other continents. In June 2007, African swine fever was isolated in the Caucasus Region of the Republic of Georgia and subsequently in neighboring countries (Armenia, Azerbaijan, and 9 states of the Russian Federation). Previous data for sequencing of 3 genes indicated that the Georgia 2007/1 isolate is closely related to isolates of genotype II, which has been identified in Mozambique, Madagascar, and Zambia. We report the complete genomic coding sequence of the Georgia 2007/1 isolate and comparison with other isolates. A genome sequence of 189,344 bp encoding 166 open reading frames (ORFs) was obtained. Phylogeny based on concatenated sequences of 125 conserved ORFs showed that this isolate clustered most closely with the Mkuzi 1979 isolate. Some ORFs clustered differently, suggesting that recombination may have occurred. Results provide a baseline for monitoring genomic changes in this virus. PMID:21470447

  3. A novel bromodeoxyuridine-resistant wild boar lung cell line facilitates generation of African swine fever virus recombinants.

    Science.gov (United States)

    Keil, Günther M; Giesow, Katrin; Portugal, Raquel

    2014-09-01

    Manipulation of African swine fever virus (ASFV) genomes, in particular those from field strains, is still a challenge. We have shown recently that generation of a green-fluorescent-protein-expressing, thymidine-kinase-negative (TK-) mutant of the low-pathogenic African swine fever virus field strain NHV was supported by a TK- Vero cell line. Since NHV, like other ASFV field strains, does not replicate well in Vero cells, a bromodeoxyuridine (BrdU)- resistant cell line derived from wild boar lung (WSL) cells, named WSL-Bu, was selected. WSL cells were used because they are suitable for productive replication of NHV and other ASFV field strains. Here, we show that WSL-Bu cells enable positive selection of both TK- and TK+ ASFV recombinants, which allows for novel strategies for construction of ASFV mutants. We further demonstrate for a low-pathogenic ASFV strain that TK expression is required for infectious replication in macrophages infected at low multiplicity and that vaccinia TK fully complements ASFV TK in this respect.

  4. Development of a novel lateral flow assay for detection of African swine fever in blood.

    Science.gov (United States)

    Sastre, P; Gallardo, C; Monedero, A; Ruiz, T; Arias, M; Sanz, A; Rueda, P

    2016-09-15

    African swine fever (ASF) is a viral infectious disease of domestic and wild suids of all breeds and ages, causing a wide range of hemorrhagic syndromes and frequently characterized by high mortality. The disease is endemic in Sub-Saharan Africa and Sardinia. Since 2007, it has also been present in different countries of Eastern Europe, where control measures have not been effective so far. The continued spread poses a serious threat to the swine industry worldwide. In the absence of vaccine, early detection of infected animals is of paramount importance for control of the outbreak, to prevent the transmission of the virus to healthy animals and subsequent spreading of the disease. Current laboratory diagnosis is mainly based on virological methods (antigen and genome detection) and serodiagnosis. In the present work, a Lateral Flow Assay (LFA) for antigen detection has been developed and evaluated. The test is based on the use of a MAb against VP72 protein of ASFV, the major viral capsid protein and highly immunogenic. First experiments using VP72 viral and recombinant protein or inactivated culture virus showed promising results with a sensitivity similar to that of a commercially available Antigen-ELISA. Moreover, these strips were tested with blood from experimentally infected pigs and field animals and the results compared with those of PCR and Antigen-ELISA. For the experimentally infected samples, there was an excellent correlation between the LFA and the ELISA, while the PCR always showed to be more sensitive (38 % positive samples by PCR versus 27 % by LFA). The LFA was demonstrated to be positive for animals with circulating virus levels exceeding 10(4) HAU. With the field samples, once again, the PCR detected more positives than either the Antigen-ELISA or LFA, although here the number of positive samples scored by the LFA exceeded the values obtained with the Antigen-ELISA, showing 60 % positivity vs 48 % for the ELISA. For the two groups of sera

  5. Unraveling the Armor of a Killer: Evasion of Host Defenses by African Swine Fever Virus.

    Science.gov (United States)

    Reis, Ana Luisa; Netherton, Chris; Dixon, Linda K

    2017-03-15

    African swine fever is an acute hemorrhagic disease of pigs. Extensive recent spread in the Russian Federation and Eastern Europe has increased the risk to global pig production. The virus is a large DNA virus and is the only member of the Asfarviridae family. In pigs, the virus replicates predominantly in macrophages. We review how the virus overcomes the barriers to replication in the macrophage and the virus mechanism to inhibit key host defense pathways. Copyright © 2017 American Society for Microbiology.

  6. 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.

  7. Simultaneous Deletion of the 9GL and UK Genes from the African Swine Fever Virus Georgia 2007 Isolate Offers Increased Safety and Protection against Homologous Challenge.

    Science.gov (United States)

    O'Donnell, Vivian; Risatti, Guillermo R; Holinka, Lauren G; Krug, Peter W; Carlson, Jolene; Velazquez-Salinas, Lauro; Azzinaro, Paul A; Gladue, Douglas P; Borca, Manuel V

    2017-01-01

    African swine fever virus (ASFV) is the etiological agent of a contagious and often lethal viral disease of domestic pigs that has significant economic consequences for the swine industry. The control of African swine fever (ASF) has been hampered by the unavailability of vaccines. Successful experimental vaccines have been derived from naturally occurring, cell culture-adapted, or genetically modified live attenuated ASFV. Recombinant viruses harboring engineered deletions of specific virulence-associated genes induce solid protection against challenge with parental viruses. Deletion of the 9GL (B119L) gene in the highly virulent ASFV isolates Malawi Lil-20/1 (Mal) and Pretoriuskop/96/4 (Δ9GL viruses) resulted in complete protection when challenged with parental isolates. When similar deletions were created within the ASFV Georgia 2007 (ASFV-G) genome, attenuation was achieved but the protective and lethal doses were too similar. To enhance attenuation of ASFV-G, we deleted another gene, UK (DP96R), which was previously shown to be involved in attenuation of the ASFV E70 isolate. Here, we report the construction of a double-gene-deletion recombinant virus, ASFV-G-Δ9GL/ΔUK. When administered intramuscularly (i.m.) to swine, there was no induction of disease, even at high doses (10 6 HAD 50 ). Importantly, animals infected with 10 4 50% hemadsorbing doses (HAD 50 ) of ASFV-G-Δ9GL/ΔUK were protected as early as 14 days postinoculation when challenged with ASFV-G. The presence of protection correlates with the appearance of serum anti-ASFV antibodies, but not with virus-specific circulating ASFV-specific gamma interferon (IFN-γ)-producing cells. ASFV-G-Δ9GL/ΔUK is the first rationally designed experimental ASFV vaccine that protects against the highly virulent ASFV Georgia 2007 isolate as early as 2 weeks postvaccination. Currently, there is no commercially available vaccine against African swine fever. Outbreaks of the disease are devastating to the swine

  8. Infection control during filoviral hemorrhagic fever outbreaks

    Directory of Open Access Journals (Sweden)

    N Raabe Vanessa

    2012-01-01

    Full Text Available Breaking the human-to-human transmission cycle remains the cornerstone of infection control during filoviral (Ebola and Marburg hemorrhagic fever outbreaks. This requires effective identification and isolation of cases, timely contact tracing and monitoring, proper usage of barrier personal protection gear by health workers, and safely conducted burials. Solely implementing these measures is insufficient for infection control; control efforts must be culturally sensitive and conducted in a transparent manner to promote the necessary trust between the community and infection control team in order to succeed. This article provides a review of the literature on infection control during filoviral hemorrhagic fever outbreaks focusing on outbreaks in a developing setting and lessons learned from previous outbreaks. The primary search database used to review the literature was PUBMED, the National Library of Medicine website.

  9. Experimental infection of pregnant gilts with swine hepatitis E virus

    OpenAIRE

    Kasorndorkbua, Chaiyan; Thacker, Brad J.; Halbur, Patrick G.; Guenette, Denis K.; Buitenwerf, Ryan M.; Royer, Ryan L.; Meng, Xiang-Jin

    2003-01-01

    To determine the effect of swine hepatitis E virus (HEV) infection on pregnant gilts, their fetuses, and offspring, 12 gilts were intravenously inoculated with swine HEV. Six gilts, who were not inoculated, served as controls. All inoculated gilts became actively infected and shed HEV in feces, but vertical transmission was not detected in the fetuses. There was no evidence of clinical disease in the gilts or their offspring. Mild multifocal lymphohistiocytic hepatitis was observed in 4 of 12...

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

    Directory of Open Access Journals (Sweden)

    Vienna R. Brown

    2018-03-01

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

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

    Science.gov (United States)

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

    2013-03-23

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

  12. FEVER AS INDICATOR TO SECONDARY INFECTION IN DENGUE VIRAL INFECTION

    Directory of Open Access Journals (Sweden)

    Soegeng Soegijanto

    2018-04-01

    Full Text Available Dengue Virus Infections are distributed in tropical and sub-tropical regions and transmitted by the mosquitoes such as Aedes aegypti and Aedes albopictus. Dengue virus can cause dengue fever, dengue hemorrhagic fever and dengue shock syndrome or dengue and severe dengue classified by World Health Organization. Beside it concurrent infection virus salmonella had been found some cases who showed fever more than 7 days. Concurrent infection with two agents can result in an illness having overlapping symptoms creating a diagnostic dilemma for treating physician, such as dengue fever with typhoid fever. The aim of this research is detection of dengue virus and secondary infection with Salmonella typhi in patients suspected dengue virus infection. Detection of dengue virus and Salmonella typhi using immunochromatography test such as NS1, IgG/IgM for dengue virus infection, and IgM/IgG Salmonella and blood culture. The fifty children with dengue virus infection came to Soerya hospital and 17 cases suspected dengue virus infection, five cases showed a positive NS1 on the second day of fever and one case concurrent with clinical manifestation of convulsi on the third days of fever there were five cases only showed positive. It was showed in this study that on the fourth to six day of fever in dengue virus infection accompanied by antibody IgM & IgG dengue. There were 12 cases showed the clinical manifestation of concurrent dengue viral infection and Salmonella, all of them showed a mild clinical manifestation and did not show plasma leakage and shock. In this study we found the length of stay of concurrent Dengue Virus Infection and Salmonella infection is more than 10 days. These patients were also more likely to have co-existing haemodynamic disturbances and bacterial septicaemia which would have required treatment with inotropes and antibiotics. This idea is very important to make update dengue viral management to decrease mortality in outbreak try to

  13. 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. Copyright © 2016 Elsevier B.V. All rights reserved.

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

    DEFF Research Database (Denmark)

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

    2013-01-01

    Self-replicating RNAs (replicons), with or without reporter gene sequences, derived from the genome of the Paderborn strain of classical swine fever virus (CSFV) have been produced. The full-length viral cDNA, propagated within a bacterial artificial chromosome (BAC), was modified by targeted......), as well as by detection of the CSFV NS3 protein production within the cells. Inclusion of the viral E2 coding region within the replicon was advantageous for the replication efficiency. Production of chimeric RNAs, substituting the NS2 and NS3 coding regions (as a unit) from the Paderborn strain...

  15. 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...... single-copy bacterial artificial chromosome (BAC) generating full-length pestivirus DNAs from which infectious RNA transcripts could be also derived. Our strategy allows construction of stable infectious BAC DNAs from a single full-length PCR product....

  16. Detection of African Swine Fever antibodies by immunoblotting assay

    African Journals Online (AJOL)

    Although the disease was once reported in Nigeria in Ogun State in 1973, it resurfaced again in 1997 through the South Western Part of the country most probably by cross boarder contact with infected pig/pig products smuggled from neighboring Benin and Cameroon Republics (Anon, 1998; Empres, 1998; Majiyagbe, ...

  17. First detection of African Swine Fever Virus in Ornithodoros porcinus in Madagascar and new insights into tick distribution and taxonomy.

    Science.gov (United States)

    Ravaomanana, Julie; Michaud, Vincent; Jori, Ferran; Andriatsimahavandy, Abel; Roger, François; Albina, Emmanuel; Vial, Laurence

    2010-11-30

    African Swine Fever Virus has devastated more than the half of the domestic pig population in Madagascar since its introduction, probably in 1997-1998. One of the hypotheses to explain its persistence on the island is its establishment in local Ornithodoros soft ticks, whose presence has been reported in the past from the north-western coast to the Central Highlands. The aim of the present study was to verify such hypothesis by conducting tick examinations in three distinct zones of pig production in Madagascar where African Swine Fever outbreaks have been regularly reported over the past decade and then to improve our knowledge on the tick distribution and taxonomy. Ornithodoros ticks were only found in one pig farm in the village of Mahitsy, north-west of Antananarivo in the Central Highlands, whereas the tick seemed to be absent from the two other study zones near Ambatondrazaka and Marovoay. Using 16SrDNA PCR amplification and sequencing, it was confirmed that the collected ticks belonged to the O. porcinus species and is closely related to the O. p. domesticus sub-species Walton, 1962. ASFV was detected in 7.14% (13/182) of the field ticks through the amplification of part of the viral VP72 gene, and their ability to maintain long-term infections was confirmed since all the ticks came from a pig building where no pigs or any other potential vertebrate hosts had been introduced for at least four years. Considering these results, O. porcinus is a reservoir for ASFV and most likely acts as vector for ASFV in Madagascar, but its apparent restricted distribution may limit its role in the epidemiology of the disease in domestic pigs.

  18. First detection of African Swine Fever Virus in Ornithodoros porcinus in Madagascar and new insights into tick distribution and taxonomy

    Directory of Open Access Journals (Sweden)

    Albina Emmanuel

    2010-11-01

    Full Text Available Abstract Background African Swine Fever Virus has devastated more than the half of the domestic pig population in Madagascar since its introduction, probably in 1997-1998. One of the hypotheses to explain its persistence on the island is its establishment in local Ornithodoros soft ticks, whose presence has been reported in the past from the north-western coast to the Central Highlands. The aim of the present study was to verify such hypothesis by conducting tick examinations in three distinct zones of pig production in Madagascar where African Swine Fever outbreaks have been regularly reported over the past decade and then to improve our knowledge on the tick distribution and taxonomy. Results Ornithodoros ticks were only found in one pig farm in the village of Mahitsy, north-west of Antananarivo in the Central Highlands, whereas the tick seemed to be absent from the two other study zones near Ambatondrazaka and Marovoay. Using 16SrDNA PCR amplification and sequencing, it was confirmed that the collected ticks belonged to the O. porcinus species and is closely related to the O. p. domesticus sub-species Walton, 1962. ASFV was detected in 7.14% (13/182 of the field ticks through the amplification of part of the viral VP72 gene, and their ability to maintain long-term infections was confirmed since all the ticks came from a pig building where no pigs or any other potential vertebrate hosts had been introduced for at least four years. Conclusions Considering these results, O. porcinus is a reservoir for ASFV and most likely acts as vector for ASFV in Madagascar, but its apparent restricted distribution may limit its role in the epidemiology of the disease in domestic pigs.

  19. Molecular approaches for the treatment of hemorrhagic fever virus infections.

    Science.gov (United States)

    Andrei, G; De Clercq, E

    1993-09-01

    Viruses causing hemorrhagic fevers in man belong to the following virus groups: togavirus (Chikungunya), flavivirus (dengue, yellow fever, Kyasanur Forest disease, Omsk hemorrhagic fever), arenavirus (Argentinian hemorrhagic fever, Bolivian hemorrhagic fever, Lassa fever), filovirus (Ebola, Marburg), phlebovirus (Rift Valley fever), nairovirus (Crimian-Congo hemorrhagic fever) and hantavirus (hemorrhagic fever with renal syndrome, nephropathic epidemia). Hemorrhagic fever virus infections can be approached by different therapeutic strategies: (i) vaccination; (ii) administration of high-titered antibodies; and (iii) treatment with antiviral drugs. Depending on the molecular target of their interaction, antiviral agents could be classified as follows: IMP dehydrogenase inhibitors (i.e., ribavirin and its derivatives); OMP decarboxylase inhibitors (i.e., pyrazofurin); CTP synthetase inhibitors (i.e., cyclopentylcytosine and cyclopentenylcytosine); SAH hydrolase inhibitors (i.e., neplanocin A); polyanionic substances (i.e., sulfated polymers); interferon and immunomodulators.

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

    Directory of Open Access Journals (Sweden)

    Lauren G Holinka

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

  1. Using mortality data for early detection of Classical Swine Fever in The Netherlands.

    Science.gov (United States)

    Backer, J A; Brouwer, H; van Schaik, G; van Roermund, H J W

    2011-04-01

    Early detection of the introduction of an infectious livestock disease is of great importance to limit the potential extent of an outbreak. Classical Swine Fever (CSF) often causes non-specific clinical signs, which can take considerable time to be detected. Currently, the disease can be detected by three main routes, that are all triggered by clinical signs. To improve the early detection of CSF an additional program, based on mortality data, aims to routinely perform PCR tests on ear notch samples from herds with a high(er) mortality. To assess the effectiveness of this new early detection system, we have developed a stochastic model that describes the virus transmission within a pig herd, the development of disease in infected animals and the different early detection programs. As virus transmission and mortality (by CSF and by other causes) are different for finishing pigs, piglets and sows, a distinction is made between these pig categories. The model is applied to an extensive database that contains all unique pig herds in The Netherlands, their herd sizes and their mortality reports over the CSF-free period 2001-2005. Results from the simulations suggest that the new early detection system is not effective in piglet sections, due to the high mortality from non-CSF causes, nor in sow sections, due to the low CSF-mortality. In finishing herds, the model predicts that the new early detection system can improve the detection time by two days, from 38 (27-53) days to 36 (24-51) days after virus introduction, when assuming a moderately virulent virus strain causing a 50% CSF mortality. For this result up to 5 ear notch samples per herd from 8 (0-13) finishing herds must be tested every workday. Detecting a source herd two days earlier could considerably reduce the number of initially infected herds. However, considering the variation in outcome and the uncertainty in some model assumptions, this two-day gain in detection time is too small to demonstrate a

  2. Evaluation of control and surveillance strategies for classical swine fever using a simulation model.

    Science.gov (United States)

    Dürr, S; Zu Dohna, H; Di Labio, E; Carpenter, T E; Doherr, M G

    2013-01-01

    Classical swine fever (CSF) outbreaks can cause enormous losses in naïve pig populations. How to best minimize the economic damage and number of culled animals caused by CSF is therefore an important research area. The baseline CSF control strategy in the European Union and Switzerland consists of culling all animals in infected herds, movement restrictions for animals, material and people within a given distance to the infected herd and epidemiological tracing of transmission contacts. Additional disease control measures such as pre-emptive culling or vaccination have been recommended based on the results from several simulation models; however, these models were parameterized for areas with high animal densities. The objective of this study was to explore whether pre-emptive culling and emergency vaccination should also be recommended in low- to moderate-density areas such as Switzerland. Additionally, we studied the influence of initial outbreak conditions on outbreak severity to improve the efficiency of disease prevention and surveillance. A spatial, stochastic, individual-animal-based simulation model using all registered Swiss pig premises in 2009 (n=9770) was implemented to quantify these relationships. The model simulates within-herd and between-herd transmission (direct and indirect contacts and local area spread). By varying the four parameters (a) control measures, (b) index herd type (breeding, fattening, weaning or mixed herd), (c) detection delay for secondary cases during an outbreak and (d) contact tracing probability, 112 distinct scenarios were simulated. To assess the impact of scenarios on outbreak severity, daily transmission rates were compared between scenarios. Compared with the baseline strategy (stamping out and movement restrictions) vaccination and pre-emptive culling neither reduced outbreak size nor duration. Outbreaks starting in a herd with weaning piglets or fattening pigs caused higher losses regarding to the number of culled

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

    International Nuclear Information System (INIS)

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

    2016-01-01

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

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

    Science.gov (United States)

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

    2018-01-01

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

  5. Identification of a New Genotype of African Swine Fever Virus in Domestic Pigs from Ethiopia.

    Science.gov (United States)

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

    2017-10-01

    African swine fever (ASF) is an important emerging transboundary animal disease (TAD), which currently has an impact on many countries in Africa, Eastern Europe, the Caucasus and the Russian Federation. The current situation in Europe shows the ability of the virus to rapidly spread, which stands to threaten the global swine industry. At present, there is no viable vaccine to minimize spread of the disease and stamping out is the main source of control. In February 2011, Ethiopia had reported its first suspected outbreaks of ASF. Genomic analyses of the collected ASF virus (ASFV) strains were undertaken using 23 tissue samples collected from domestic swine in Ethiopia from 2011 to 2014. The analysis of Ethiopian ASFVs partial p72 gene sequence showed the identification of a new genotype, genotype XXIII, that shares a common ancestor with genotypes IX and X, which comprise isolates circulating in Eastern African countries and the Republic of Congo. Analysis of the p54 gene also followed the p72 pattern and the deduced amino acid sequence of the central variable region (CVR) of the B602L gene showed novel tetramer repeats not previously characterized. © 2016 The Authors. Transboundary and Emerging Diseases Published by Blackwell Verlag GmbH.

  6. Comparative characterization analysis of synonymous codon usage bias in classical swine fever virus.

    Science.gov (United States)

    Xu, Xin; Fei, Dongliang; Han, Huansheng; Liu, Honggui; Zhang, Jiayong; Zhou, Yulong; Xu, Chuang; Wang, Hongbin; Cao, Hongwei; Zhang, Hua

    2017-06-01

    Classical swine fever virus (CSFV) is responsible for the highly contagious viral disease of swine, and causes great economic loss in the swine-raising industry. Considering the significance of CSFV, a systemic analysis was performed to study its codon usage patterns. In this study, using the complete genome sequences of 76 CSFV representing three genotypes, we firstly analyzed the relative nucleotide composition, effective number of codon (ENC) and synonymous codon usage in CSFV genomes. The results showed that CSFV is GC-moderate genome and the third-ended codons are not preferentially used. Every ENC values in CSFV genomes are >50, indicating that the codon usage bias is comparatively slight. Subsequently, we performed the correspondence analysis (COA) to investigate synonymous codon usage variation among all of the CSFV genomes. We found that codon usage bias in these CSFV genomes is greatly influenced by G + C mutation, which suggests that mutational pressure may be the main factor determining the codon usage biases. Moreover, most of the codon usage bias among different CSFV ORFs is directly related to the nucleotide composition. Other factors, such as hydrophobicity and aromaticity, also influence the codon usage variation among CSFV genomes. Our study represents the most comprehensive analysis of codon usage patterns in CSFV genome and provides a basic understanding of the mechanisms for its codon usage bias. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. 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

  8. Pigs immunized with a novel E2 subunit vaccine are protected from subgenotype heterologous classical swine fever virus challenge.

    Science.gov (United States)

    Madera, Rachel; Gong, Wenjie; Wang, Lihua; Burakova, Yulia; Lleellish, Karen; Galliher-Beckley, Amy; Nietfeld, Jerome; Henningson, Jamie; Jia, Kaimin; Li, Ping; Bai, Jianfa; Schlup, John; McVey, Scott; Tu, Changchun; Shi, Jishu

    2016-09-09

    Classical swine fever (CSF) or hog cholera is a highly contagious swine viral disease. CSF endemic countries have to use routine vaccination with modified live virus (MLV) vaccines to prevent and control CSF. However, it is impossible to serologically differentiate MLV vaccinated pigs from those infected with CSF virus (CSFV). The aim of this study is to develop a one-dose E2-subunit vaccine that can provide protection against CSFV challenge. We hypothesize that a vaccine consisting of a suitable adjuvant and recombinant E2 with natural conformation may induce a similar level of protection as the MLV vaccine. Our experimental vaccine KNB-E2 was formulated with the recombinant E2 protein (Genotype 1.1) expressed by insect cells and an oil-in-water emulsion based adjuvant. 10 pigs (3 weeks old, 5 pigs/group) were immunized intramuscularly with one dose or two doses (3 weeks apart) KNB-E2, and 10 more control pigs were administered normal saline solution only. Two weeks after the second vaccination, all KNB-E2 vaccinated pigs and 5 control pigs were challenged with 5 × 10(5) TCID50 CSFV Honduras/1997 (Genotype 1.3, 1 ml intramuscular, 1 ml intranasal). It was found that while control pigs infected with CSFV stopped growing and developed high fever (>40 °C), high level CSFV load in blood and nasal fluid, and severe leukopenia 3-14 days post challenge, all KNB-E2 vaccinated pigs continued to grow as control pigs without CSFV exposure, did not show any fever, had low or undetectable level of CSFV in blood and nasal fluid. At the time of CSFV challenge, only pigs immunized with KNB-E2 developed high levels of E2-specific antibodies and anti-CSFV neutralizing antibodies. Our studies provide direct evidence that pigs immunized with one dose KNB-E2 can be protected clinically from CSFV challenge. This protection is likely mediated by high levels of E2-specific and anti-CSFV neutralizing antibodies.

  9. Influenza A virus infections in swine: pathogenesis and diagnosis.

    Science.gov (United States)

    Janke, B H

    2014-03-01

    Influenza has been recognized as a respiratory disease in swine since its first appearance concurrent with the 1918 "Spanish flu" human pandemic. All influenza viruses of significance in swine are type A, subtype H1N1, H1N2, or H3N2 viruses. Influenza viruses infect epithelial cells lining the surface of the respiratory tract, inducing prominent necrotizing bronchitis and bronchiolitis and variable interstitial pneumonia. Cell death is due to direct virus infection and to insult directed by leukocytes and cytokines of the innate immune system. The most virulent viruses consistently express the following characteristics of infection: (1) higher or more prolonged virus replication, (2) excessive cytokine induction, and (3) replication in the lower respiratory tract. Nearly all the viral proteins contribute to virulence. Pigs are susceptible to infection with both human and avian viruses, which often results in gene reassortment between these viruses and endemic swine viruses. The receptors on the epithelial cells lining the respiratory tract are major determinants of infection by influenza viruses from other hosts. The polymerases, especially PB2, also influence cross-species infection. Methods of diagnosis and characterization of influenza viruses that infect swine have improved over the years, driven both by the availability of new technologies and by the necessity of keeping up with changes in the virus. Testing of oral fluids from pigs for virus and antibody is a recent development that allows efficient sampling of large numbers of animals.

  10. Lumbricidae as transitory hosts in Metastrongylus infection in swine

    Directory of Open Access Journals (Sweden)

    Pavlović Ivan

    2005-01-01

    Full Text Available Metastrongylidosis or lungworm disease in swine is a disease caused by several types of nematodes of the genus Metastrongylus. Metastrongylidae are biohelminths whose causes use transitory hosts for their development and maintaining their biological cycle, and in this case they are numerous species of Lumbricidae (earthworms. Depending on the geographic environment, numerous representatives of Lumbricidae persist as transitory hosts. In our environment, these are dominant earthworm species of the genus Eisenia spp, Dandreobena spp, Allopbophora spp, Lubricus spp, Octoiasium spp, Bimastus spp, and rarely those from the genus Heledrillus spp. Swine are infected perorally with Metastrongylidae when they ingest infected earthworms.

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

    NARCIS (Netherlands)

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

    2008-01-01

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

  12. Molecular diagnostics of swine infection caused by Mycoplasma suis

    Directory of Open Access Journals (Sweden)

    Potkonjak Aleksandar

    2009-01-01

    Full Text Available The presence of two types of haemoplasm can be established in the swine population. Pathogenic haemoplasm, named Mycoplasma suis (previously called Eperythrozoon suis is the cause of swine eperythrozoonosis or swine ichtheroanaemia. The cause of this disease can also infect humans. The disease has spread all over the world. The most frequent form is latent infection of swine caused by M. suis. The disease is clinically manifest following action by the stress factor. The acute course of the disease is characterized by the occurrence of a febrile condition and ichtheroanaemia. The disease is usually diagnosed based on an epizootiological poll, a clinical examination, and a microscopic examination of a blood smear stained most often according to Giemsa. Contemporary methods of molecular biology have been developed, such as PCR, which are more sensitive and specific in making a diagnosis of swine infection caused by M. suis. In these investigations, the presence of M. suis on pig farms in the Republic of Serbia has been determined using the PCR test. .

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

    Science.gov (United States)

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

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

    DEFF Research Database (Denmark)

    Rangelova, Desislava Yordanova

    a new DIVA vaccine candidate. The vaccine candidate “CP7E2alf” is intended for either intramuscular vaccination of domestic pig or for bait vaccination of wild boar. In this thesis as part of the clinical testing of the injection vaccine the efficacy of “CP7E2alf” was evaluated in young piglets...... that were positive for maternally derived antibodies (MDA). These antibodies were obtained with colostrum from their mothers vaccinated with traditional live attenuated vaccine C-strain (Riems). The promising results concerning the safety and the efficacy of the candidate DIVA vaccine showed new......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...

  15. 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

    and duration of the epidemic, the number of depopulated and/or vaccinated herds and animals, the control costs borne by the public and the pig industry, respectively, as well as the loss of exports associated with the epidemic. The simulations showed that the EUplus strategy is the most effective......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...

  16. 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.

  17. 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.,...

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

    Directory of Open Access Journals (Sweden)

    Marisa Arias

    2017-10-01

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

  19. The L83L ORF of African swine fever virus strain Georgia encodes for a non-essential gene that interacts with host protein IL-1ß

    Science.gov (United States)

    African swine fever virus (ASFV) causes a contagious and frequently lethal disease of pigs that produces significant economic consequences to the swine industry. ASFV genome encodes for more than 150 genes, but only a few of them have been studied in detail. Here we report the characterization of op...

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

    Directory of Open Access Journals (Sweden)

    Raquel Muñoz-Moreno

    2015-04-01

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

  1. Classical swine fever outbreak containment using antiviral supplementation: a potential alternative to emergency vaccination and stamping-out.

    Science.gov (United States)

    Ribbens, S; Goris, N; Neyts, J; Dewulf, J

    2012-09-01

    Classical swine fever (CSF) outbreaks may result in huge economic losses to countries with densely populated pig areas (DPLAs). The EU minimum control measures require depopulation of infected farms, movement restrictions, zoning and surveillance (EU Minimum strategy). Emergency vaccination is authorised for DPLAs although the EU Minimum strategy plus culling in a 1-km ring around infected premises is preferred. Nonetheless, vaccination in a 2-km ring has been found equally effective as 1-km ring culling using stochastic modelling. Alternatives control measures (e.g. antiviral agents, in particular small molecule inhibitors of the CSFV replication) are being explored. Hence, the present study was set up to simulate inter-herd CSFV spread when antiviral molecules are supplemented to pig feed in a 1-km ring around infected farms. The effectiveness of the antiviral strategy for containing CSF outbreaks was compared to six other control scenarios including the EU Minimum strategy, the EU preferred policy for DPLAs and the use of 2-km ring vaccination. The InterSpread Plus model was adapted to the 2006 Belgian pig population and outbreak simulations were performed with a fast spreading CSFV strain entering a DPLA in Belgium. Four out of the seven control strategies resulted in outbreaks that were controlled by the end of the simulation period (i.e. 365 days). The distributions of the number of infected herds and the duration of the predicted outbreaks for these four control strategies were not different. This is the first report investigating CSF outbreak containment using antiviral molecules. Although antiviral supplementation was not found to perform any better than some other conventional strategies, such as pre-emptive culling and emergency vaccination, it might be worthwhile considering it further as additional tool in a response to CSF outbreaks. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. African swine fever virus is enveloped by a two-membraned collapsed cisterna derived from the endoplasmic reticulum.

    Science.gov (United States)

    Andrés, G; García-Escudero, R; Simón-Mateo, C; Viñuela, E

    1998-11-01

    During the cytoplasmic maturation of African swine fever virus (ASFV) within the viral factories, the DNA-containing core becomes wrapped by two shells, an inner lipid envelope and an outer icosahedral capsid. We have previously shown that the inner envelope is derived from precursor membrane-like structures on which the capsid layer is progressively assembled. In the present work, we analyzed the origin of these viral membranes and the mechanism of envelopment of ASFV. Electron microscopy studies on permeabilized infected cells revealed the presence of two tightly apposed membranes within the precursor membranous structures as well as polyhedral assembling particles. Both membranes could be detached after digestion of intracellular virions with proteinase K. Importantly, membrane loop structures were observed at the ends of open intermediates, which suggests that the inner envelope is derived from a membrane cisterna. Ultraestructural and immunocytochemical analyses showed a close association and even direct continuities between the endoplasmic reticulum (ER) and assembling virus particles at the bordering areas of the viral factories. Such interactions become evident with an ASFV recombinant that inducibly expresses the major capsid protein p72. In the absence of the inducer, viral morphogenesis was arrested at a stage at which partially and fully collapsed ER cisternae enwrapped the core material. Together, these results indicate that ASFV, like the poxviruses, becomes engulfed by a two-membraned collapsed cisterna derived from the ER.

  3. 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.

  4. 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

  5. Histopathological and immunohistochemical findings of swine with spontaneous influenza A infection in Brazil, 2009-2010

    Directory of Open Access Journals (Sweden)

    Tatiane T.N. Watanabe

    2012-11-01

    Full Text Available Swine influenza (SI is caused by the type A swine influenza virus (SIV. It is a highly contagious disease with a rapid course and recovery. The major clinical signs and symptoms are cough, fever, anorexia and poor performance. The disease has been associated with other co-infections in many countries, but not in Brazil, where, however, the first outbreak has been reported in 2011. The main aim of this study was to characterize the histological features in association with the immunohistochemical (IHC results for influenza A (IA, porcine circovirus type 2 (PCV2 and porcine reproductive and respiratory syndrome virus (PRRSV in lung samples from 60 pigs submitted to Setor de Patologia Veterinária at the Universidade Federal do Rio Grande do Sul (SPV-UFRGS, Brazil, during 2009-2010. All of these lung samples had changes characterized by interstitial pneumonia with necrotizing bronchiolitis, never observed previously in the evaluation of swine lungs in our laboratory routine. Pigs in this study had showed clinical signs of a respiratory infection. Swine samples originated from Rio Grande do Sul 31 (52%, Santa Catarina 14 (23%, Paraná 11 (18%, and Mato Grosso do Sul 4 (7%. Positive anti-IA IHC labelling was observed in 45% of the cases, which were associated with necrotizing bronchiolitis, atelectasis, purulent bronchopneumonia and hyperemia. Moreover, type II pneumocyte hyperplasia, alveolar and bronchiolar polyp-like structures, bronchus-associated lymphoid tissue (BALT hyperplasia and pleuritis were the significant features in negative anti-IA IHC, which were also associated with chronic lesions. There were only two cases with positive anti-PCV2 IHC and none to PRRSV. Therefore, SIV was the predominant infectious agent in the lung samples studied. The viral antigen is often absent due to the rapid progress of SI, which may explain the negative IHC results for IA (55%; therefore, IHC should be performed at the beginning of the disease. This study

  6. Rift Valley fever potential mosquito vectors and their infection status ...

    African Journals Online (AJOL)

    Background: Rift Valley fever (RVF) is a mosquito-borne viral zoonotic disease. Rift Valley fever virus (RVFV) has been isolated from more than 40 species of mosquitoes from eight genera. This study was conducted to determine the abundance of potential mosquito vectors and their RVFV infection status in Ngorongoro ...

  7. IL-23/IL-17/G-CSF pathway is associated with granulocyte recruitment to the lung during African swine fever.

    Science.gov (United States)

    Karalyan, Z; Voskanyan, H; Ter-Pogossyan, Z; Saroyan, D; Karalova, E

    2016-10-15

    The interleukin (IL)-23/IL-17 pathway plays a crucial role in various forms of inflammation but its function in acute African swine fever (ASF) is not well understood. Thus, in this study, we aimed to find out whether IL-23/IL-17/G-CSF is released in acute ASF and what function it may have. The present study revealed that the production of IL-17 and IL-23 were significantly increased in the sera of ASFV infected pigs. Using ELISA, we found that the serum levels of IL-23 and IL-17 have overexpressed in ASF virus infected pigs compared with healthy controls. The levels of IL-17 and IL-23 increase in the early stages and the levels of G-CSF and C - reactive protein in the later stages of ASF. Simultaneously, with the increase of the levels of IL-23/IL-17 extravasation of granular leukocytes in the tissue (diapedesis) is observed. Diapedesis can explain the neutropenia that we identified previously in the terminal stages of ASF. The increase in serum levels of IL-23/IL-17 is preceded by enhanced migration of neutrophils in tissues, and the last one is preceded by neutropenia. The increase in serum levels of G-CSF has compensatory nature, directed on stimulation of proliferation of granulocytes. Taken together, our results revealed an overexpression of the IL-23/IL-17 axis in the ASF virus infected pigs, suggesting that it may be a crucial pathway in the diapedesis at ASF. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Interactive cellular proteins related to classical swine fever virus non-structure protein 2 by yeast two-hybrid analysis.

    Science.gov (United States)

    Kang, Kai; Guo, Kangkang; Tang, Qinhai; Zhang, Yanming; Wu, Jiang; Li, Weiwei; Lin, Zhi

    2012-12-01

    Classical swine fever is caused by the classical swine fever virus (CSFV), which has a special affinity to endothelial cells. This fever is characterized by hemorrhage and necrosis of vascular injury. Very little information is available on the interaction between vascular endothelial cells and CSFV. In the current report, the cDNA library of swine umbilical vein endothelial cell (SUVEC) was constructed by the switching mechanism at 5' end of the RNA transcript approach. The yeast two-hybrid (Y2H) system was adopted to screen non-structure 2 protein (NS2) interactive proteins in the SUVEC line. Alignment with the NCBI database revealed 11 interactive proteins: GOPC, HNRNPH1, DNAJA1, ATP6, CSDE1, CNDP2, FANCL, TMED4, DNAJA4, MOAP1, and PNMA1. These proteins were mostly related to apoptosis, stress response and oxidation reduction, or metabolism. In the protein interaction network constructed based on proteins with NS2, the more important proteins were MOAP1, DNAJA1, GOPC, FANCL, TMED4, and CSDE1. The interactions detected by the Y2H should be regarded only as preliminary indications. However, the CSFV NS2 interactive proteins in the SUVEC cDNA library obtained in the current study provides valuable information for gaining a better understanding of the host protein-virus interactions of the CSFV NS2 protein.

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

    DEFF Research Database (Denmark)

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

    2015-01-01

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

  10. Acute infection of swine by various Salmonella serovars.

    Science.gov (United States)

    Loynachan, A T; Nugent, J M; Erdman, M M; Harris, D L

    2004-07-01

    The objective of this study was to evaluate the ability of various serovars of Salmonella enterica subsp. enterica to infect alimentary and nonalimentary tissues of swine within 3 h of inoculation. Fourteen wild-type S. enterica serovars (4,12:imonophasic, 6,7 nonmotile, Agona, Brandenburg, Bredeney, Derby, Heidelberg, Infantis, Muenchen, Thompson, Typhimurium, Typhimurium variant Copenhagen, untypeable, and Worthington), two known virulent S. enterica serovars (Choleraesuis strain SC-38 and Typhimurium strain chi4232), and two avirulent S. enterica Choleraesuis vaccine strains (Argus and SC-54) were inoculated intranasally (approximately 5 x 10(9) cells) into swine (four animals per Salmonella isolate). Three hours after inoculation, animals were euthanized, and both alimentary tissues (tonsil, colon contents, and cecum contents) and nonalimentary tissues (mandibular lymph node, thymus, lung, liver, spleen, ileocecal lymph node, and blood) were collected for Salmonella isolation. All Salmonella serovars evaluated except Salmonella Choleraesuis SC-54 acutely infected both alimentary and nonalimentary tissues. These results indicate that Salmonella isolates commonly found in swine are capable of acutely infecting both alimentary and nonalimentary tissues in a time frame consistent with that in which animals are transported and held in lairage prior to slaughter.

  11. Comparison of virological methods applied on african swine fever diagnosis in Brazil, 1978

    Directory of Open Access Journals (Sweden)

    Tânia Rosária Pereira Freitas

    2015-10-01

    Full Text Available ABSTRACT. Freitas T.R.P., Souza A.C., Esteves E.G. & Lyra T.M.P. [Comparison of virological methods applied on african swine fever diagnosis in Brazil, 1978.] Comparação dos métodos virológicos aplicados no diagnóstico da peste suína africana no Brasil, 1978. Revista Brasileira de Medicina Veterinária, 37(3:255-263, 2015. Laboratório Nacional Agropecuário, Ministério da Agricultura, Pecuária e Abastecimento, Avenida Rômulo Joviano, s/n, Caixa postal 35/50, Pedro Leopoldo, MG 33600-000, Brasil. taniafrei@hotmail.com The techniques of leucocytes haemadsorption (HAD for the African Swine Fever (ASF virus isolation and the fluorescent antigens tissue samples (FATS for virus antigens detection were implanted in the ASF eradication campaign in the country. The complementary of techniques was studied considering the results obtained when the HAD and FATS were concomitantly applied on the same pig tissue samples. The results of 22, 56 and 30 pigs samples from of the States of Rio de Janeiro (RJ, São Paulo (SP and Paraná (PR, respectively, showed that in RJ 11 (50%; in SP, 28 (50% and in PR, 15 (50% samples were positive in the HAD, while, RJ, 18 (82%; SP, 33 (58% and PR, 17 (57% were positive in the FATS. In the universe of 108 samples submitted to both the tests, 83 (76.85% were positive in at least one of the tests, which characterized ASF positivity. Among the positive samples, 28 (34% have presented HAD negative results and 15 (18% have presented FATS negative results. The achievement of applying simultaneously the both tests was the reduction of false- negative results, conferring more ASF accurate laboratorial diagnosis, besides to show the tests complementary. This aspect is fundamentally importance concern with a disease eradiation program to must avoid false negative results. Evidences of low virulence ASFV strains in Brazilian ASF outbreaks and also the distribution of ASF outbreaks by the mesoregions of each State were discussed

  12. Comparison of Asian porcine high fever disease isolates of porcine reproductive and respiratory syndrome virus to United States isolates for their ability to cause disease and secondary bacterial infection in swine

    Science.gov (United States)

    Epidemiologic data from Asian outbreaks of highly-pathogenic (HP) porcine reproductive and respiratory syndrome virus (PRRSV) suggest that disease severity was associated with both the virulence of the PRRSV isolates and secondary bacterial infections. Previous reports have indicated that U.S. isola...

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

    Science.gov (United States)

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

    2013-10-25

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

  14. 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. © 2015 Blackwell Verlag GmbH.

  15. 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. © 2014 Blackwell Verlag GmbH.

  16. [Severe clinical problems lasting several weeks on a multiplier pig farm: what if it had been classical swine fever?].

    Science.gov (United States)

    Backer, Jantien; Spierenburg, Marcel; van der Spek, Arco; Elbers, Armin

    2010-10-15

    In the Spring of 2009, a veterinarian reported suspected classical swine fever (CSF) on a multiplier pig farm in the southern part of The Netherlands (close to the Belgian border). Over a 5-week period there had been a number of sick sows and an excessively high percentage of stillborn and preterm piglets. Sick animals were treated with anti-inflammatory drugs and antibiotics, but did not respond as well as anticipated. A visiting specialist team from the Food Safety Authority could not exclude CSF as the cause of the clinical problems and sent blood samples to the reference laboratory in Lelystad for a PCR test on CSF antigen. Fortunately, test results obtained 6 hours later were negative for CSF, and the disease control measures were lifted. It later appeared that porcine reproductive and respiratory syndrome (PRRSV) might have been responsible for the problems. But what if CSF had caused the clinical problems? A CSF-transmission model was used to simulate CSF outbreaks dependent on the duration of the high-risk period (HRP). As the duration of the HRP increased, there was an exponential growth in the number of pig farms infected during this period. Simulations also showed that with a longer HRP, the virus spread over greater distances from the source herd. It was also investigated whether a possible CSF outbreak could be detected on the basis of an increased mortality and hence increased number of cadavers sent to a rendering plant. However, the calculated mortality incidence was not sensitive enough to serve as an alarm signal. It is recommended that CSF-exclusion diagnostics be used much earlier in similar clinical situations on pig farms.

  17. 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.

  18. Helicobacter pylori infection and typhoid fever in Jakarta, Indonesia.

    NARCIS (Netherlands)

    Vollaard, A.M.; Verspaget, H.W.; Ali, S.; Visser, L.G.; Veenendaal, R.A.; Asten, H.A.G.H. van; Widjaja, S.; Surjadi, C.; Dissel, J.T. van

    2006-01-01

    We evaluated the association between typhoid fever and Helicobacter pylori infection, as the latter microorganism may influence gastric acid secretion and consequently increase susceptibility to Salmonella typhi infection. Anti-H. pylori IgG and IgA antibody titres (ELISA) and gastrin concentration

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

    Directory of Open Access Journals (Sweden)

    Damarys Relova

    2017-12-01

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

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

    Science.gov (United States)

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

    2005-09-12

    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 threat to the pig production sector in The Netherlands. Reducing the annual probability of CSFV introduction (P(CSFV)) by preventive measures is therefore of utmost importance. The choice of preventive measures depends not only on the achieved reduction of the annual P(CSFV), but also on the expenditures required for implementing these measures. The objective of this study was to explore the cost-effectiveness of tactical measures aimed at the prevention of CSFV introduction into The Netherlands. For this purpose for each measure (i) model calculations were performed with a scenario tree model for CSFV introduction and (ii) its annual cost was estimated. The cost-effectiveness was then determined as the reduction of the annual P(CSFV) achieved by each preventive measure (DeltaP) divided by the annual cost of implementing that measure (DeltaC). The measures analysed reduce the P(CSFV) caused by import or export of pigs. Results showed that separation of national and international transport of pigs is the most cost-effective measure, especially when risk aversion is assumed. Although testing piglets and breeding pigs by a quick and reliable PCR also had a high cost-effectiveness ratio, this measure is not attractive due to the high cost per pig imported. Besides, implementing such a measure is not allowed under current EU law, as it is trade restrictive.

  3. [Present status of an arbovirus infection: yellow fever, its natural history of hemorrhagic fever, Rift Valley fever].

    Science.gov (United States)

    Digoutte, J P

    1999-12-01

    In the early 20th century, when it was discovered that the yellow fever virus was transmitted in its urban cycle by Aedes aegypti, measures of control were introduced leading to its disappearance. Progressive neglect of the disease, however, led to a new outbreak in 1927 during which the etiological agent was isolated; some years later a vaccine was discovered and yellow fever disappeared again. In the 1960s, rare cases of encephalitis were observed in young children after vaccination and the administration of the vaccine was forbidden for children under 10 years. Five years later, a new outbreak of yellow fever in Diourbel, Senegal, was linked to the presence of Aedes aegypti. In the late 1970s, the idea of a selvatic cycle for yellow fever arose. Thanks to new investigative techniques in Senegal and Côte d'Ivoire, the yellow fever virus was isolated from the reservoir of virus and vectors. The isolated virus was identified in monkeys and several vectors: Aedes furcifer, Aedes taylori, Aedes luteocephalus. Most importantly, the virus was isolated in male mosquitoes. Until recently, the only known cycle had been that of Haddow in East Africa. The virus circulate in the canopea between monkeys and Aedes africanus. These monkeys infect Aedes bromeliae when they come to eat in banana plantations. This cycle does not occur in West Africa. Vertical transmission is the main method of maintenance of the virus through the dry season. "Reservoirs of virus" are often mentioned in medical literature, monkeys having a short viremia whereas mosquitoes remain infected throughout their life cycle. In such a selvatic cycle, circulation can reach very high levels and no child would be able to escape an infecting bite and yet no clinical cases of yellow fever have been reported. The virulence--as it affects man--of the yellow fever virus in its wild cycle is very low. In areas where the virus can circulate in epidemic form, two types of circulation can be distinguished

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

    DEFF Research Database (Denmark)

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

    2007-01-01

    A method for quantitative evaluation of surveillance for disease freedom has been presented in the accompanying paper (Martin et al., 2007). This paper presents an application of the methods, using as an example surveillance for classical swine fever (CSF) in Denmark in 2005. A scenario tree model......) associated with age and location (county), and disease clustering within herds. A surveillance time period of one month was used in the analysis. Records for the year 2005 were analysed, representing 25,332 samples from 3528 herds; all were negative for CSF-specific antibodies. Design prevalences of 0...

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

    DEFF Research Database (Denmark)

    McKillan, John; McMenamy, Michael; Hjertner, Bernt

    2010-01-01

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

  6. 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. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. From Q Fever to Coxiella burnetii Infection: a Paradigm Change

    Science.gov (United States)

    Eldin, Carole; Mélenotte, Cléa; Mediannikov, Oleg; Ghigo, Eric; Million, Matthieu; Edouard, Sophie; Mege, Jean-Louis; Maurin, Max

    2016-01-01

    SUMMARY Coxiella burnetii is the agent of Q fever, or “query fever,” a zoonosis first described in Australia in 1937. Since this first description, knowledge about this pathogen and its associated infections has increased dramatically. We review here all the progress made over the last 20 years on this topic. C. burnetii is classically a strict intracellular, Gram-negative bacterium. However, a major step in the characterization of this pathogen was achieved by the establishment of its axenic culture. C. burnetii infects a wide range of animals, from arthropods to humans. The genetic determinants of virulence are now better known, thanks to the achievement of determining the genome sequences of several strains of this species and comparative genomic analyses. Q fever can be found worldwide, but the epidemiological features of this disease vary according to the geographic area considered, including situations where it is endemic or hyperendemic, and the occurrence of large epidemic outbreaks. In recent years, a major breakthrough in the understanding of the natural history of human infection with C. burnetii was the breaking of the old dichotomy between “acute” and “chronic” Q fever. The clinical presentation of C. burnetii infection depends on both the virulence of the infecting C. burnetii strain and specific risks factors in the infected patient. Moreover, no persistent infection can exist without a focus of infection. This paradigm change should allow better diagnosis and management of primary infection and long-term complications in patients with C. burnetii infection. PMID:27856520

  8. 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.

  9. Prenatal Exposure to Fever and Infections and Academic Performance

    DEFF Research Database (Denmark)

    Dreier, Julie Werenberg; Berg-Beckhoff, Gabriele; Kragh Andersen, Per

    2017-01-01

    of academic performance from the 2010–2013 Danish National Tests. Hierarchical multilevel linear regression of 216,350 assessments made in 71,850 children born to 67,528 mothers revealed no differences in academic performance among the children according to prenatal exposure to fever (odds ratio (OR) = 1......Prenatal exposure to fever and infections has been linked to various neurodevelopmental disorders, but it is not yet known whether more subtle effects on neurodevelopment may exist as well. Therefore, we aimed to investigate whether these early-life exposures were associated with academic...... performance in childhood and early adolescence. Children and mothers who were enrolled in the Danish National Birth Cohort during 1996–2002 were included in this study. Information on fever and infections common in pregnancy was prospectively collected in 2 pregnancy interviews and linked with assessments...

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

    Science.gov (United States)

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

    2015-02-01

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

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

    Science.gov (United States)

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

    2017-10-15

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

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

    Science.gov (United States)

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

    2017-09-01

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

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

    Science.gov (United States)

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

    2018-01-01

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

  14. Prevalence of Bartonella infection among patients with fever ...

    African Journals Online (AJOL)

    Bartonella henselae has been associated with an increasing spectrum of clinical syndromes including cat scratch disease. The prevalence of Bartonella infection among patients with unexplained fever in San Francisco was much greater than has previously been documented. However, out of 29 Japanese children with ...

  15. Rift Valley fever potential mosquito vectors and their infection status ...

    African Journals Online (AJOL)

    conducted to determine the abundance of potential mosquito vectors and their RVFV infection status in. Ngorongoro District ... Rift Valley fever (RVF) is an acute febrile arthropod-borne viral zoonotic disease of mainly human ..... A.S., Rollin, P.E., Swanepoel, R., Ksiazek, T.G. & Nichol, S.T. (2002) Genetic analysis of viruses.

  16. Modelling the time at which overcrowding and feed interruption emerge on the swine premises under movement restrictions during a classical swine fever outbreak.

    Science.gov (United States)

    Weng, H Y; Yadav, S; Olynk Widmar, N J; Croney, C; Ash, M; Cooper, M

    2017-03-01

    A stochastic risk model was developed to estimate the time elapsed before overcrowding (TOC) or feed interruption (TFI) emerged on the swine premises under movement restrictions during a classical swine fever (CSF) outbreak in Indiana, USA. Nursery (19 to 65 days of age) and grow-to-finish (40 to 165 days of age) pork production operations were modelled separately. Overcrowding was defined as the total weight of pigs on premises exceeding 100% to 115% of the maximum capacity of the premises, which was computed as the total weight of the pigs at harvest/transition age. Algorithms were developed to estimate age-specific weight of the pigs on premises and to compare the daily total weight of the pigs with the threshold weight defining overcrowding to flag the time when the total weight exceeded the threshold (i.e. when overcrowding occurred). To estimate TFI, an algorithm was constructed to model a swine producer's decision to discontinue feed supply by incorporating the assumptions that a longer estimated epidemic duration, a longer time interval between the age of pigs at the onset of the outbreak and the harvest/transition age, or a longer progression of an ongoing outbreak would increase the probability of a producer's decision to discontinue the feed supply. Adverse animal welfare conditions were modelled to emerge shortly after an interruption of feed supply. Simulations were run with 100 000 iterations each for a 365-day period. Overcrowding occurred in all simulated iterations, and feed interruption occurred in 30% of the iterations. The median (5th and 95th percentiles) TOC was 24 days (10, 43) in nursery operations and 78 days (26, 134) in grow-to-finish operations. Most feed interruptions, if they emerged, occurred within 15 days of an outbreak. The median (5th and 95th percentiles) time at which either overcrowding or feed interruption emerged was 19 days (4, 42) in nursery and 57 days (4, 130) in grow-to-finish operations. The study findings suggest that

  17. 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...

  18. 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

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

    NARCIS (Netherlands)

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

    1996-01-01

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

  20. 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,

  1. A novel spatial and stochastic model to evaluate the within- and between-farm transmission of classical swine fever virus. I. General concepts and description of the model.

    Science.gov (United States)

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

    2011-01-27

    A new stochastic and spatial model was developed to evaluate the potential spread of classical swine fever virus (CSFV) within- and between-farms, and considering the specific farm-to-farm contact network. Within-farm transmission was simulated using a modified SI model. Between-farm transmission was assumed to occur by direct contacts (i.e. animal movement) and indirect contacts (i.e. local spread, vehicle and person contacts) and considering the spatial location of farms. Control measures dictated by the European legislation (i.e. depopulation of infected farms, movement restriction, zoning, surveillance, contact tracing) were also implemented into the model. Model experimentation was performed using real data from Segovia, one of the provinces with highest density of pigs in Spain, and results were presented using the mean, 95% probability intervals [95% PI] and risk maps. The estimated mean [95% PI] number of infected, quarantined and depopulated farms were 3 [1,17], 23 [0,76] and 115 [0,318], respectively. The duration of the epidemic was 63 [26,177] days and the most important way of transmission was associated with local spread (61.4% of the infections). Results were consistent with the spread of previous CSFV introductions into the study region. The model and results presented here may be useful for the decision making process and for the improvement of the prevention and control programmes for CSFV. Copyright © 2010 Elsevier B.V. All rights reserved.

  2. 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

  3. Antigenic differentiation of classical swine fever vaccinal strain PAV-250 from other strains, including field strains from Mexico.

    Science.gov (United States)

    Mendoza, Susana; Correa-Giron, Pablo; Aguilera, Edgar; Colmenares, Germán; Torres, Oscar; Cruz, Tonatiuh; Romero, Andres; Hernandez-Baumgarten, Eliseo; Ciprián, Abel

    2007-10-10

    Twenty-nine classical swine fever virus (CSFv) strains were grown in the PK15 or SK6 cell lines. Antigenic differentiation studies were performed using monoclonal antibodies (McAbs), produced at Lelystad (CDI-DLO), The Netherlands. The monoclonals which were classified numerically as monoclonals 2-13. Epitope map patterns that resulted from the reactivity with McAbs were found to be unrelated to the pathogenicity of the viruses studied. Antigenic determinants were recognized by McAbs 5 and 8, were not detected in some Mexican strains; however, sites for McAb 6 were absent in all strains. The PAV-250 vaccine strain was recognized by all MAbs, except by MAb 6. Furthermore, the Chinese C-S vaccine strain was found to be very similar to the GPE(-) vaccine. None of the studied Mexican vaccines or field strains was found to be similar to the PAV-250 vaccine strain.

  4. African swine fever virus encodes for an E2-ubiquitin conjugating enzyme that is mono- and di-ubiquitinated and required for viral replication cycle.

    Science.gov (United States)

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

    2018-02-22

    African swine fever virus is the etiological agent of a contagious and fatal acute haemorrhagic viral disease for which there are no vaccines or therapeutic options. The ASFV encodes for a putative E2 ubiquitin conjugating enzyme (ORF I215L) that shows sequence homology with eukaryotic counterparts. In the present study, we showed that pI215L acts as an E2-ubiquitin like enzyme in a large range of pH values and temperatures, after short incubation times. Further experiments revealed that pI215L is polyubiquitinated instead of multi-mono-ubiquitinated and Cys85 residue plays an essential role in the transthioesterification reaction. In infected cells, I215L gene is transcribed from 2 hours post infection and immunoblot analysis confirmed that pI215L is expressed from 4 hpi. Immunofluorescence studies revealed that pI215L is recruited to viral factories from 8 hpi and a diffuse distribution pattern throughout the nucleus and cytoplasm. siRNA studies suggested that pI215L plays a critical role in the transcription of late viral genes and viral DNA replication. Altogether, our results emphasize the potential use of this enzyme as target for drug and vaccine development against ASF.

  5. The effect of vaccination with the PAV-250 strain classical swine fever (CSF) virus on the airborne transmission of CSF virus.

    Science.gov (United States)

    Gonzalez, C; Pijoan, C; Ciprian, A; Correa, P; Mendoza, S

    2001-09-01

    The airborne transmission of Classical Swine Fever (CSF) virus to susceptible pigs, as well as the effect of vaccination with the CSF virus PAV-250 strain was investigated on this mode of transmission. Experiment I: four pigs were inoculated with the ALD CSFV strain (10(4.3) 50% TCID) by the intramuscular route, and at the onset of fever, they were introduced into an enclosed chamber. At the end of the experiment surviving pigs were sedated, anesthetized and euthanatized. Experiment II: four pigs were previously vaccinated with the CSF virus PAV-250 strain, and at 14 days post-vaccination they were challenged with the CSF virus ALD strain. In both experiments, four susceptible pigs were exposed to infectious aerosols by placing them in a chamber connected by a duct to the adjacent pen containing the infected animals and were kept there for 86 hs. In Experiment I, pigs exposed to contaminated air died as a result of infection with CSF virus on days 14, 21 and 28 post-inhalation. These four pigs seroconverted from day 12 post-inhalation. CSF virus was isolated from these animals, and the fluorescent antibody test on tonsils was positive. In Experiment II, a vaccinated pig exposed to contaminated air did not seroconvert, nor was CSF virus isolated from lymphoid tissues. However, mild fluorescence in tonsil sections from these pigs was observed. In conclusion, CSF virus was shown to be transmitted by air at a distance of 1 m to susceptible pigs. Vaccination with the PAV-250 CSF virus strain protected the pigs from clinical disease under the same conditions.

  6. Identification of atypical porcine pestivirus infection in swine herds in China.

    Science.gov (United States)

    Zhang, K; Wu, K; Liu, J; Ge, S; Xiao, Y; Shang, Y; Ning, Z

    2017-08-01

    Atypical porcine pestivirus (APPV) have been detected in swine herds from the USA, Germany, the Netherlands, Spain and most recently in Austria, suggesting a wide geographic distribution of this novel virus. Here, for the first time, we reported APPV infection in swine herds in China. Newborn piglets from two separate swine herds in Guangdong province were found showing typical congenital tremors in July and August 2016. RT-PCR, sequencing and phylogenetic analysis showed APPV infection occurred. Phylogenetic analysis showed that Chinese APPV strains, GD1 and GD2, formed independent branch from the USA, Germany and the Netherlands. Nucleotide identities between members of the APPV ranged between 83.1% and 83.5%, and this showed APPV is highly diverse. It is apparent that this provides the first molecular evidence of APPV infection in swine herds in China. © 2017 Blackwell Verlag GmbH.

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

    Science.gov (United States)

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

    2017-08-23

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

  8. Development, optimization, and validation of a Classical swine fever virus real-time reverse transcription polymerase chain reaction assay.

    Science.gov (United States)

    Eberling, August J; Bieker-Stefanelli, Jill; Reising, Monica M; Siev, David; Martin, Barbara M; McIntosh, Michael T; Beckham, Tammy R

    2011-09-01

    Classical swine fever (CSF) is an economically devastating disease of pigs. Instrumental to the control of CSF is a well-characterized assay that can deliver a rapid, accurate diagnosis prior to the onset of clinical signs. A real-time fluorogenic-probe hydrolysis (TaqMan) reverse transcription polymerase chain reaction (RT-PCR) for CSF was developed by the United States Department of Agriculture (USDA) at the Plum Island Animal Disease Center (CSF PIADC assay) and evaluated for analytical and diagnostic sensitivity and specificity. A well-characterized panel including Classical swine fever virus (CSFV), Bovine viral diarrhea virus (BVDV), and Border disease virus (BDV) isolates was utilized in initial feasibility and optimization studies. The assay was initially designed and validated for use on the ABI 7900HT using the Qiagen QuantiTect® Probe RT-PCR chemistry. However, demonstrating equivalency with multiple one-step RT-PCR chemistries and PCR platforms increased the versatility of the assay. Limit of detection experiments indicated that the Qiagen QuantiTect® Multiplex (NoROX) and the Invitrogen SuperScript® III RT-PCR kits were consistently the most sensitive one-step chemistries for use with the CSF PIADC primer/probe set. Analytical sensitivity of the CSF PIADC assay ranged from <1-2.95 log(10) TCID(50)/ml on both the ABI 7900HT and ABI 7500 platforms. The CSF PIADC assay had 100% diagnostic sensitivity and specificity when tested on a panel of 152 clinical samples from the Dominican Republic and Colombia. The ability to perform this newly developed assay in 96-well formats provides an increased level of versatility for use in CSF surveillance programs.

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

    Science.gov (United States)

    Madera, Rachel Flores; Wang, Lihua; Gong, Wenjie; Burakova, Yulia; Buist, Sterling; Nietfeld, Jerome; Henningson, Jamie; Ozuna, Ada G Cino; Tu, Changchun; Shi, Jishu

    2018-03-06

    The highly contagious classical swine fever (CSF) remains a major trade and health problem in the pig industry, causing large economic losses worldwide. Modified live vaccines (MLV), commonly derived from the attenuated CSF virus (CSFV) C-strain, have been routinely used to control the disease in CSF-endemic countries. However, to completely eradicate the disease, a potent, safe and non-infectious CSF vaccine should be easily accessible and available. This study aims to develop a cost-effective, non infectious CSF subunit vaccine that can elicit rapid and long lasting immunity. We report on a series of animal studies to study the efficacy of a CSF E2 subunit vaccine in oil-in-water emulsion adjuvant, KNB-E2. Swine vaccination and CSFV challenge experiments showed that a single KNB-E2 dose with 25 µg of recombinant CSFV glycoprotein E2 can reduce disease and protect from clinical symptoms. In addition, KNB-E2-mediated reduction of CSF symptoms was observed at two weeks post vaccination and the vaccinated pigs continued to exhibit reduced CSF clinical signs when challenged at two months and four months post vaccination. These results suggest that KNB-E2 effectively reduces CSF clinical signs and the potential of this vaccine to safely minimize CSF-related losses.

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

    Directory of Open Access Journals (Sweden)

    Ye Chen

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

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

    Science.gov (United States)

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

    2017-03-01

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

  12. Fatal disease associated with Swine Hepatitis E virus and Porcine circovirus 2 co-infection in four weaned pigs in China.

    Science.gov (United States)

    Yang, Yifei; Shi, Ruihan; She, Ruiping; Mao, Jingjing; Zhao, Yue; Du, Fang; Liu, Can; Liu, Jianchai; Cheng, Minheng; Zhu, Rining; Li, Wei; Wang, Xiaoyang; Soomro, Majid Hussain

    2015-03-26

    In recent decades, Porcine circovirus 2 (PCV2) infection has been recognized as the causative agent of postweaning multisystemic wasting syndrome, and has become a threat to the swine industry. Hepatitis E virus (HEV) is another high prevalent pathogen in swine in many regions of the world. PCV2 and HEV are both highly prevalent in pig farms in China. In this study, we characterized the HEV and PCV2 co-infection in 2-3 month-old piglets, based on pathogen identification and the pathological changes observed, in Hebei Province, China. The pathological changes were severe, and general hyperemia, hemorrhage, inflammatory cell infiltration, and necrosis were evident in the tissues of dead swine. PCR was used to identify the pathogen and we tested for eight viruses (HEV, Porcine reproductive and respiratory syndrome virus, PCV2, Classical swine fever virus, Porcine epidemic diarrhea virus, Transmissible gastroenteritis coronavirus, Porcine parvovirus and Pseudorabies virus) that are prevalent in Chinese pig farms. The livers, kidneys, spleens, and other organs of the necropsied swine were positive for HEV and/or PCV2. Immunohistochemical staining showed HEV- and PCV2-antigen-positive signals in the livers, kidneys, lungs, lymph nodes, and intestine. HEV and PCV2 co-infection in piglets was detected in four out of seven dead pigs from two pig farms in Hebei, China, producing severe pathological changes. The natural co-infection of HEV and PCV2 in pigs in China has rarely been reported. We speculate that co-infection with PCV2 and HEV may bring some negative effect on pig production and recommend that more attention should be paid to this phenomenon.

  13. Comparison of detection methods for Toxoplasma gondii in naturally and experimentally infected swine.

    Science.gov (United States)

    Hill, Dolores E; Chirukandoth, Sreekumar; Dubey, J P; Lunney, Joan K; Gamble, H Ray

    2006-10-10

    Results from recent serological surveys and epidemiological studies show that pigs raised in a variety of management systems can be carriers of the tissue cyst stage of Toxoplasma gondi. This parasite can be transmitted to humans through the consumption of improperly prepared pork, making detection and removal of infected swine carcasses from the food chain an important food safety issue. Several methods are available for detection of T. gondii infected swine, including serological assays, polymerase chain reaction, and animal bioassays. The aim of the present study was to compare the detection sensitivities of six of these commonly used methods for detection of T. gondii infection in tissues from naturally and experimentally infected pigs. The results indicate that a serum-based ELISA is the most sensitive method, of those tested, for detection of T. gondii infected swine.

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

    Science.gov (United States)

    Rossi, Sophie; Toigo, Carole; Hars, Jean; Pol, Françoise; Hamann, Jean-Luc; Depner, Klaus; Le Potier, Marie-Frederique

    2011-01-01

    The understanding of host-parasite systems in wildlife is of increasing interest in relation to the risk of emerging diseases in livestock and humans. In this respect, many efforts have been dedicated to controlling classical swine fever (CSF) in the European Wild Boar. But CSF eradication has not always been achieved even though vaccination has been implemented at a large-scale. Piglets have been assumed to be the main cause of CSF persistence in the wild since they appeared to be more often infected and less often immune than older animals. However, this assumption emerged from laboratory trials or cross-sectional surveys based on the hunting bags. In the present paper we conducted a capture-mark-recapture study in free-ranging wild boar piglets that experienced both CSF infection and vaccination under natural conditions. We used multi-state capture recapture models to estimate the immunization and infection rates, and their variations according to the periods with or without vaccination. According to the model prediction, 80% of the infected piglets did not survive more than two weeks, while the other 20% quickly recovered. The probability of becoming immune did not increase significantly during the summer vaccination sessions, and the proportion of immune piglets was not higher after the autumn vaccination. Given the high lethality of CSF in piglets highlighted in our study, we consider unlikely that piglets could maintain the chain of CSF virus transmission. Our study also revealed the low efficacy of vaccination in piglets in summer and autumn, possibly due to the low palatability of baits to that age class, but also to the competition between baits and alternative food sources. Based on this new information, we discuss the prospects for the improvement of CSF control and the interest of the capture-recapture approach for improving the understanding of wildlife diseases.

  15. A novel spatial and stochastic model to evaluate the within and between farm transmission of classical swine fever virus: II validation of the model.

    Science.gov (United States)

    Martínez-López, B; Ivorra, B; Ngom, D; Ramos, A M; Sánchez-Vizcaíno, J M

    2012-02-24

    A new, recently published, stochastic and spatial model for the evaluation of classical swine fever virus (CSFV) spread into Spain has been validated by using several methods. Internal validity, sensitivity analysis, validation using historical data, comparison with other models and experiments on data validity were used to evaluate the overall reliability and consistency of the model. More than 100 modifications in input data and parameters were evaluated. Outputs were obtained after 1000 iterations for each new scenario of the model. As a result, the model was shown to be consistent, being the probability of infection by local spread, the time from infectious to clinical signs state, the probability of detection based on clinical signs at day t after detection of the index case outside the control and surveillance zones and the maximum number of farms to be depopulated at day t the parameters that have more influence (>10% of change) on the magnitude and duration of the epidemic. The combination of a within- and between-farm spread model was also shown to give significantly different results than using a purely between-farm spread model. Methods and results presented here were intended to be useful to better understand and apply the model, to identify key parameters for which it will be critical to have good estimates and to provide better support for prevention and control of future CSFV outbreaks. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. Effective surveillance strategies following a potential classical Swine Fever incursion in a remote wild pig population in North-Western Australia.

    Science.gov (United States)

    Leslie, E; Cowled, B; Graeme Garner, M; Toribio, J-A L M L; Ward, M P

    2014-10-01

    Early disease detection and efficient methods of proving disease freedom can substantially improve the response to incursions of important transboundary animal diseases in previously free regions. We used a spatially explicit, stochastic disease spread model to simulate the spread of classical swine fever in wild pigs in a remote region of northern Australia and to assess the performance of disease surveillance strategies to detect infection at different time points and to delineate the size of the resulting outbreak. Although disease would likely be detected, simple random sampling was suboptimal. Radial and leapfrog sampling improved the effectiveness of surveillance at various stages of the simulated disease incursion. This work indicates that at earlier stages, radial sampling can reduce epidemic length and achieve faster outbreak delineation and control, but at later stages leapfrog sampling will outperform radial sampling in relation to supporting faster disease control with a less-extensive outbreak area. Due to the complexity of wildlife population dynamics and group behaviour, a targeted approach to surveillance needs to be implemented for the efficient use of resources and time. Using a more situation-based surveillance approach and accounting for disease distribution and the time period over which an epidemic has occurred is the best way to approach the selection of an appropriate surveillance strategy. © 2013 Blackwell Verlag GmbH.

  17. Analysis of spatio-temporal patterns of African swine fever cases in Russian wild boar does not reveal an endemic situation.

    Science.gov (United States)

    Lange, M; Siemen, H; Blome, S; Thulke, H-H

    2014-11-15

    African swine fever (ASF) is a highly lethal viral disease of domestic pigs and wild boar. ASF was introduced into the southern Russian Federation in 2007 and is now reported to be spreading in populations of wild and domestic suids. An endemic situation in the local wild boar population would significantly complicate management of the disease in the livestock population. To date no sound method exists for identifying the characteristic pattern of an endemic situation, which describes infection persisting from generation to generation in the same population. To support urgent management decisions at the wildlife-livestock interface, a new algorithm was constructed to test the hypothesis of an endemic disease situation in wildlife on the basis of case reports. The approach described here uses spatial and temporal associations between observed diagnostic data to discriminate between endemic and non-endemic patterns of case occurrence. The algorithm was validated with data from an epidemiological simulation model and applied to ASF case data from southern Russia. Based on the algorithm and the diagnostic data available, the null hypothesis of an endemic situation of ASF in wild boar of the region was rejected. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. 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.

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

    DEFF Research Database (Denmark)

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

    2008-01-01

    of CSFV between the hypothetical wild-boar population and the domestic population. Furthermore, the economic impact is assessed taking the perspective of the Danish national budget and the Danish pig industry. We used InterSpreadPlus to model the differential classical swine fever (CSF) risk due to wild...... boar. Nine scenarios were run to elucidate the effect of: (a) presence of wild boar (yes/no), (b) locations for the index case (domestic pig herd/wild-boar group),...

  20. Differentiated swine airway epithelial cell cultures for the investigation of influenza A virus infection and replication.

    Science.gov (United States)

    Bateman, Allen C; Karasin, Alexander I; Olsen, Christopher W

    2013-03-01

    Differentiated human airway epithelial cell cultures have been utilized to investigate cystic fibrosis, wound healing, and characteristics of viral infections. These cultures, grown at an air-liquid interface (ALI) in media with defined hormones and growth factors, recapitulate many aspects of the in vivo respiratory tract and allow for experimental studies at the cellular level. To optimize growth conditions for differentiated swine airway epithelial cultures and to use these cultures to examine influenza virus infection and replication. Primary swine respiratory epithelial cells were grown at an air-liquid interface with varying amounts of retinoic acid and epidermal growth factor. Cells grown with optimized concentrations of these factors for 4 weeks differentiated into multilayer epithelial cell cultures resembling the lining of the swine respiratory tract. Influenza virus infection and replication were examined in these cultures. Retinoic acid promoted ciliogenesis, whereas epidermal growth factor controlled the thickness of the pseudoepithelium. The optimal concentrations for differentiated swine cell cultures were 1·5 ng/ml epidermal growth factor and 100nm retinoic acid. Influenza A viruses infected and productively replicated in these cultures in the absence of exogenous trypsin, suggesting that the cultures express a protease capable of activating influenza virus hemagglutinin. Differences in virus infection and replication characteristics found previously in pigs in vivo were recapitulated in the swine cultures. This system could be a useful tool for a range of applications, including investigating influenza virus species specificity, defining cell tropism of influenza viruses in the swine respiratory epithelium, and studying other swine respiratory diseases. © 2012 Blackwell Publishing Ltd.

  1. 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

  2. Partial Activation of Natural Killer and γδ T Cells by Classical Swine Fever Viruses Is Associated with Type I Interferon Elicited from Plasmacytoid Dendritic Cells

    Science.gov (United States)

    Franzoni, Giulia; Edwards, Jane C.; Kurkure, Nitin V.; Edgar, Daniel S.; Sanchez-Cordon, Pedro J.; Haines, Felicity J.; Salguero, Francisco J.; Everett, Helen E.; Bodman-Smith, Kikki B.; Crooke, Helen R.

    2014-01-01

    Vaccination with live attenuated classical swine fever virus (CSFV) vaccines can rapidly confer protection in the absence of neutralizing antibodies. With an aim of providing information on the cellular mechanisms that may mediate this protection, we explored the interaction of porcine natural killer (NK) cells and γδ T cells with CSFV. Both NK and γδ T cells were refractory to infection with attenuated or virulent CSFV, and no stimulatory effects, as assessed by the expression of major histocompatibility complex (MHC) class II (MHC-II), perforin, and gamma interferon (IFN-γ), were observed when the cells were cultured in the presence of CSFV. Coculture with CSFV and myeloid dendritic cells (mDCs) or plasmacytoid dendritic cells (pDCs) showed that pDCs led to a partial activation of both NK and γδ T cells, with upregulation of MHC-II being observed. An analysis of cytokine expression by infected DC subsets suggested that this effect was due to IFN-α secreted by infected pDCs. These results were supported by ex vivo analyses of NK and γδ T cells in the tonsils and retropharyngeal lymph nodes from pigs that had been vaccinated with live attenuated CSFV and/or virulent CSFV. At 5 days postchallenge, there was evidence of significant upregulation of MHC-II but not perforin on NK and γδ T cells, which was observed only following a challenge of the unvaccinated pigs and correlated with increased CSFV replication and IFN-α expression in both the tonsils and serum. Together, these data suggest that it is unlikely that NK or γδ T cells contribute to the cellular effector mechanisms induced by live attenuated CSFV. PMID:25080554

  3. Differentiation of Acute Q Fever from Other Infections in Patients Presenting to Hospitals, the Netherlands(1)

    NARCIS (Netherlands)

    Keijmel, S.P.; Krijger, E.; Delsing, C.E.; Sprong, T.; Nabuurs-Franssen, M.H.; Bleeker-Rovers, C.P.

    2015-01-01

    Differentiating acute Q fever from infections caused by other pathogens is essential. We conducted a retrospective case-control study to evaluate differences in clinical signs, symptoms, and outcomes for 82 patients with acute Q fever and 52 control patients who had pneumonia, fever and lower

  4. Association between infection and fever in terminations of pregnancy using misoprostol : A retrospective cohort study

    NARCIS (Netherlands)

    Nijman, Tobias A.J.; Voogdt, Kevin G.J.A.; Teunissen, Pim W.; van der Voorn, Patrick J.J.P.; de Groot, Christianne J.M.; Bakker, Petra C.A.M.

    2017-01-01

    Background: Fever is a well-known side effect of misoprostol, but clinically difficult to distinguish from an intra uterine infection. The aim of this study was to determine the incidence of fever in terminations of pregnancy (TOP) using misoprostol and to evaluate fever as indication of intra

  5. Spatio-temporal Analysis of African Swine Fever in Sardinia (2012-2014): Trends in Domestic Pigs and Wild Boar.

    Science.gov (United States)

    Iglesias, I; Rodríguez, A; Feliziani, F; Rolesu, S; de la Torre, A

    2017-04-01

    African swine fever (ASF) is a notifiable viral disease affecting domestic pigs and wild boars that has been endemic in Sardinia since 1978. Several risk factors complicate the control of ASF in Sardinia: generally poor level of biosecurity, traditional breeding practices, illegal behaviour in movements and feeding of pigs, and sporadic occurrence of long-term carriers. A previous study describes the disease in Sardinia during 1978-2013. The aim of this study was to gain more in-depth knowledge of the spatio-temporal pattern of ASF in Sardinia during 2012 to May 2014, comparing patterns of occurrence in domestic pigs and wild boar and identifying areas of local transmission. African swine fever notifications were studied considering seasonality, spatial autocorrelation, spatial point pattern and spatio-temporal clusters. Results showed differences in temporal and spatial pattern of wild boar and domestic pig notifications. The peak in wild boar notifications (October 2013 to February 2014) occurred six months after than in domestic pig (May to early summer 2013). Notifications of cases in both host species tended to be clustered, with a maximum significant distance of spatial association of 15 and 25 km in domestic pigs and wild boars, respectively. Five clusters for local ASF transmission were identified for domestic pigs, with a mean radius and duration of 4 km (3-9 km) and 38 days (6-55 days), respectively. Any wild boar clusters were found. The apparently secondary role of wild boar in ASF spread in Sardinia could be explained by certain socio-economic factors (illegal free-range pig breeding or the mingling of herds. The lack of effectiveness of previous surveillance and control programmes reveals the necessity of employing a new approach). Results present here provide better knowledge of the dynamics of ASF in Sardinia, which could be used in a more comprehensive risk analysis necessary to introduce a new approach in the eradication strategy. © 2015

  6. Findings of bacterial microflora in piglets infected with conventional swine plague

    Directory of Open Access Journals (Sweden)

    Prodanov Jasna

    2002-01-01

    Full Text Available Piglets infected with the conventional swine plague virus as a result of secondary bacterial infections sometimes show an insufficiently clear clinical and pathoanatomical picture, which is why the very procedure of diagnosis is complex and the final diagnosis unreliable. That is why these investigations were aimed at examining the presence of bacterial microflora in diseased and dead pilgets which were found to have the viral antigen for CSP using the fluorescent antibody technique, in cases where the pathomorphological finding was not characteristic for conventional swine plague. Autopsies of dead piglets most often showed changes in the digestive tract and lungs, with resulting technopathy and diseases of infective nature. Such findings on knowledge of a present bacterial microflora are especially important in cases when conventional swine plague is controlled on farms and an announcement that the disease has been contained is in the offing.

  7. 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. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. 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. Copyright © 2016 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

  9. Enzyme Linked Immunosorbent Assay Test for Antibody of Classical Swine Fever Virus In Timor-Leste (UJI ENZYME LINKED IMMUNOSORBENT ASSAY TERHADAP ANTIBODI VIRUS CLASSICAL SWINE FEVER DI TIMOR-LESTE

    Directory of Open Access Journals (Sweden)

    Rui Daniel de Carvalho

    2017-01-01

    Full Text Available The objective of this study was to evaluate the implementation of Classical Swine Fever (CSFvaccination on pigs in Timor-Leste. The study was conducted by analyzing the percentage of CSF antibodyin pigs sera that obtained from pigs in four districts which were located in the hills and coast of Timor-Leste. Evaluation was also carried out by observing the dominant factor that affecting the increase ofantibody titers in the sera. A total of 240 pigs sera were taken before and after vaccination and thenchecked for antibodies against of CSF virus by using PrioCheck CSFV Ab ELISA kits (Prionics Ag. Twohundred and forty serums obtained from non-vaccinated pigs and 240 other serum obtained from the samepigs, after being vaccinated with CSF vaccine. Time interval from the first and the second serum collectionwas at least 14 days post-vaccination. The results showed there was a significant difference (P<0.01 forthe presence of antibody in vaccinated pigs compared with the unvaccinated. A total of 75% serum fromvaccinated pigs was found positive for the antibody containing, while only 16.7% of serum from nonvaccinatedpigs was positive. The odd ratio analysis showed that the most influential factor for theincrease of antibody titer against CSF virus was vaccination status. among the other factors of age, sexand geographical study.

  10. Deletion of African swine fever virus interferon inhibitors from the genome of a virulent isolate reduces virulence in domestic pigs and induces a protective response.

    Science.gov (United States)

    Reis, Ana Luisa; Abrams, Charles C; Goatley, Lynnette C; Netherton, Chris; Chapman, Dave G; Sanchez-Cordon, Pedro; Dixon, Linda K

    2016-09-07

    African swine fever virus (ASFV) encodes multiple copies of MGF360 and MGF530/505 gene families. These genes have been implicated in the modulation of the type I interferon (IFN) response. We investigated the effect of modulating the IFN response on virus attenuation and induction of protective immunity by deleting genes MGF360 (MGF360-10L, 11L, 12L, 13L, 14L) and MGF530/505 (MGF530/505-1R, 2R and 3R) and interrupting genes (MGF360-9L and MGF530/505-4R) in the genome of the virulent ASFV isolate Benin 97/1. Replication of this deletion mutant, BeninΔMGF, in porcine macrophages in vitro was similar to that of the parental virulent virus Benin 97/1 and the natural attenuated isolate OURT88/3, which has a similar deletion of MGF360 and 530/505 genes. Levels of IFN-β mRNA in macrophages infected with virulent Benin 97/1 isolate were barely detectable but high levels were detected in macrophages infected with OURT88/3 and intermediate levels in macrophages infected with BeninΔMGF. The data confirms that these MGF360 and MGF530/505 genes have roles in suppressing induction of type I IFN. Immunisation and boost of pigs with BeninΔMGF showed that the virus was attenuated and all pigs (5/5) were protected against challenge with a lethal dose of virulent Benin 97/1. A short transient fever was observed at day 5 or 6 post-immunisation but no other clinical signs. Following immunisation and boost with the OURT88/3 isolate 3 of 4 pigs were protected against challenge. Differences were observed in the cellular and antibody responses in pigs immunised with BeninΔMGF compared to OURT88/3. Deletion of IFN modulators is a promising route for construction of rationally attenuated ASFV candidate vaccine strains. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  11. The effect of fermentable carbohydrates on experimental swine dysentery and whip worm infections in pigs

    DEFF Research Database (Denmark)

    Thomsen, Lisbeth E.; Knudsen, Knud Erik Bach; Jensen, Tim Kåre

    2007-01-01

    An experiment was conducted to study the effect of diets with contrasting fermentability in the large intestine on experimental infections with Brachyspira hyodysenteriae, the causative agent of swine dysentery, and the whip worm, Trichuris suis, in pigs. Two diets with organically grown ingredie......An experiment was conducted to study the effect of diets with contrasting fermentability in the large intestine on experimental infections with Brachyspira hyodysenteriae, the causative agent of swine dysentery, and the whip worm, Trichuris suis, in pigs. Two diets with organically grown...

  12. Deletion of the African Swine Fever Virus Gene DP148R Does Not Reduce Virus Replication in Culture but Reduces Virus Virulence in Pigs and Induces High Levels of Protection against Challenge.

    Science.gov (United States)

    Reis, Ana L; Goatley, Lynnette C; Jabbar, Tamara; Sanchez-Cordon, Pedro J; Netherton, Christopher L; Chapman, David A G; Dixon, Linda K

    2017-12-15

    Many of the approximately 165 proteins encoded by the African swine fever virus (ASFV) genome do not have significant similarity to known proteins and have not been studied experimentally. One such protein is DP148R. We showed that the DP148R gene is transcribed at early times postinfection. Deletion of this gene did not reduce virus replication in macrophages, showing that it is not essential for replication in these cells. However, deletion of this gene from a virulent isolate, Benin 97/1, producing the BeninΔDP148R virus, dramatically reduced the virulence of the virus in vivo All pigs infected with the BeninΔDP148R virus survived infection, showing only transient mild clinical signs soon after immunization. Following challenge with the parental virulent virus, all pigs immunized by the intramuscular route (11/11) and all except one immunized by the intranasal route (5/6) survived. Mild or no clinical signs were observed after challenge. As expected, control nonimmune pigs developed signs of acute African swine fever (ASF). The virus genome and infectious virus were observed soon after immunization, coincident with the onset of clinical signs (∼10 6 genome copies or 50% tissue culture infective doses/ml). The levels of the virus genome declined over an extended period up to 60 days postimmunization. In contrast, infectious virus was no longer detectable by days 30 to 35. Gamma interferon (IFN-γ) was detected in serum between days 4 and 7 postimmunization, and IFN-γ-producing cells were detected in all pigs analyzed following stimulation of immune lymphocytes with whole virus. ASFV-specific antibodies were first detected from day 10 postimmunization. IMPORTANCE African swine fever (ASF) is endemic in Africa, parts of the Trans Caucasus, the Russian Federation, and several European countries. The lack of a vaccine hinders control. Many of the ASF virus genes lack similarity to known genes and have not been characterized. We have shown that one of these, DP

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

    Directory of Open Access Journals (Sweden)

    Jihui Lin

    2017-08-01

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

  14. Recurrent paratyphoid fever A co-infected with hepatitis A reactivated chronic hepatitis B.

    Science.gov (United States)

    Liu, Yanling; Xiong, Yujiao; Huang, Wenxiang; Jia, Bei

    2014-05-12

    We report here a case of recurrent paratyphoid fever A with hepatitis A co-infection in a patient with chronic hepatitis B. A 26-year-old male patient, who was a hepatitis B virus carrier, was co-infected with Salmonella enterica serovar Paratyphi A and hepatitis A virus. The recurrence of the paratyphoid fever may be ascribed to the coexistence of hepatitis B, a course of ceftriaxone plus levofloxacin that was too short and the insensitivity of paratyphoid fever A to levofloxacin. We find that an adequate course and dose of ceftriaxone is a better strategy for treating paratyphoid fever. Furthermore, the co-infection of paratyphoid fever with hepatitis A may stimulate cellular immunity and break immunotolerance. Thus, the administration of the anti-viral agent entecavir may greatly improve the prognosis of this patient with chronic hepatitis B, and the episodes of paratyphoid fever and hepatitis A infection prompt the use of timely antiviral therapy.

  15. Control of African swine fever virus replication by small interfering RNA targeting the A151R and VP72 genes.

    Science.gov (United States)

    Keita, Djénéba; Heath, Livio; Albina, Emmanuel

    2010-01-01

    African swine fever virus (ASFV) is the unique member of the Asfarviridae family and Asfivirus genus. It is an enveloped double-stranded DNA arbovirus that replicates in the cell cytoplasm, similar to poxviruses. There is no vaccine and no treatment available to control this virus. We describe the use of small interfering RNA (siRNA) targeting the A151R and VP72 (B646L) genes to control the ASFV replication in vitro. Results suggest that siRNA targeting the A151R and VP72 genes can reduce both the virus replication and its levels of messenger RNA transcripts. The reduction was up to 4 log(10) copies on the virus titre and up to 3 log(10) copies on virus RNA transcripts levels. The combination of multiple siRNA did not improve the antiviral effect significantly, compared with use of individual siRNAs. The function of the A151R gene product in the virus replication cycle is yet unclear, but is essential. We also demonstrate that it is possible to inhibit, using small interfering RNA, a virus that replicates exclusively in the cell cytoplasm in specific viral factories.

  16. Comprehensive phylogenetic reconstructions of African swine fever virus: proposal for a new classification and molecular dating of the virus.

    Science.gov (United States)

    Michaud, Vincent; Randriamparany, Tantely; Albina, Emmanuel

    2013-01-01

    African swine fever (ASF) is a highly lethal disease of domestic pigs caused by the only known DNA arbovirus. It was first described in Kenya in 1921 and since then many isolates have been collected worldwide. However, although several phylogenetic studies have been carried out to understand the relationships between the isolates, no molecular dating analyses have been achieved so far. In this paper, comprehensive phylogenetic reconstructions were made using newly generated, publicly available sequences of hundreds of ASFV isolates from the past 70 years. Analyses focused on B646L, CP204L, and E183L genes from 356, 251, and 123 isolates, respectively. Phylogenetic analyses were achieved using maximum likelihood and Bayesian coalescence methods. A new lineage-based nomenclature is proposed to designate 35 different clusters. In addition, dating of ASFV origin was carried out from the molecular data sets. To avoid bias, diversity due to positive selection or recombination events was neutralized. The molecular clock analyses revealed that ASFV strains currently circulating have evolved over 300 years, with a time to the most recent common ancestor (TMRCA) in the early 18(th) century.

  17. African swine fever outbreak on a medium-sized farm in Uganda: biosecurity breaches and within-farm virus contamination.

    Science.gov (United States)

    Chenais, Erika; Sternberg-Lewerin, Susanna; Boqvist, Sofia; Liu, Lihong; LeBlanc, Neil; Aliro, Tonny; Masembe, Charles; Ståhl, Karl

    2017-02-01

    In Uganda, a low-income country in east Africa, African swine fever (ASF) is endemic with yearly outbreaks. In the prevailing smallholder subsistence farming systems, farm biosecurity is largely non-existent. Outbreaks of ASF, particularly in smallholder farms, often go unreported, creating significant epidemiological knowledge gaps. The continuous circulation of ASF in smallholder settings also creates biosecurity challenges for larger farms. In this study, an on-going outbreak of ASF in an endemic area was investigated on farm level, including analyses of on-farm environmental virus contamination. The study was carried out on a medium-sized pig farm with 35 adult pigs and 103 piglets or growers at the onset of the outbreak. Within 3 months, all pigs had died or were slaughtered. The study included interviews with farm representatives as well as biological and environmental sampling. ASF was confirmed by the presence of ASF virus (ASFV) genomic material in biological (blood, serum) and environmental (soil, water, feed, manure) samples by real-time PCR. The ASFV-positive biological samples confirmed the clinical assessment and were consistent with known virus characteristics. Most environmental samples were found to be positive. Assessment of farm biosecurity, interviews, and the results from the biological and environmental samples revealed that breaches and non-compliance with biosecurity protocols most likely led to the introduction and within-farm spread of the virus. The information derived from this study provides valuable insight regarding the implementation of biosecurity measures, particularly in endemic areas.

  18. RNA Seq analysis for transcriptome profiling in response to classical swine fever vaccination in indigenous and crossbred pigs.

    Science.gov (United States)

    Pathak, Shalu Kumari; Kumar, Amit; Bhuwana, G; Sah, Vaishali; Upmanyu, Vikramadiya; Tiwari, A K; Sahoo, A P; Sahoo, A R; Wani, Sajjad A; Panigrahi, Manjit; Sahoo, N R; Kumar, Ravi

    2017-09-01

    In present investigation, differential expression of transcriptome after classical swine fever (CSF) vaccination has been explored at the cellular level in crossbred and indigenous (desi) piglets. RNA Sequencing by Expectation-Maximization (RSEM) package was used to quantify gene expression from RNA Sequencing data, and differentially expressed genes (DEGs) were identified using EBSeq, DESeq2, and edgeR softwares. After analysis, 5222, 6037, and 6210 common DEGs were identified in indigenous post-vaccinated verses pre-vaccinated, crossbred post-vaccinated verses pre-vaccinated, and post-vaccinated crossbred verses indigenous pigs, respectively. Functional annotation of these DEGs showed enrichment of antigen processing-cross presentation, B cell receptor signaling, T cell receptor signaling, NF-κB signaling, and TNF signaling pathways. The interaction network among the immune genes included more number of genes with greater connectivity in vaccinated crossbred than the indigenous piglets. Higher expression of IRF3, IL1β, TAP1, CSK, SLA2, SLADM, and NF-kB in crossbred piglets in comparison to indigenous explains the better humoral response observed in crossbred piglets. Here, we predicted that the processed CSFV antigen through the T cell receptor signaling cascade triggers the B cell receptor-signaling pathway to finally activate MAPK kinase and NF-κB signaling pathways in B cell. This activation results in expression of genes/transcription factors that lead to B cell ontogeny, auto immunity and immune response through antibody production. Further, immunologically important genes were validated by qRT-PCR.

  19. 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.

  20. A novel ViewRNA in situ hybridization method for the detection of the dynamic distribution of Classical Swine Fever Virus RNA in PK15 cells.

    Science.gov (United States)

    Zhang, Qianyi; Xu, Lu; Zhang, Yujie; Wang, Tuanjie; Zou, Xingqi; Zhu, Yuanyuan; Zhao, Yan; Li, Cui; Chen, Kai; Sun, Yongfang; Sun, Junxiang; Zhao, Qizu; Wang, Qin

    2017-04-18

    Classical swine fever (CSF) is a highly contagious fatal infectious disease caused by classical swine fever virus (CSFV). A better understanding of CSFV replication is important for the study of pathogenic mechanism of CSF. With the development of novel RNA in situ Hybridization method, quantitatively localization and visualization of the virus RNA molecular in cultured cell or tissue section becomes very important tool to address these pivotal pathogenic questions. In this study, we established ViewRNA ISH method to reveal the dynamic distribution of CSFV RNA in PK15 cells. We designed several specific probes of CSFV RNA and reference gene β-actin for host PK15 cells to monitor the relative location of CSFV RNA and house-keeping gene in the infected cells. After determining the titer of reference strain CSFV (HeBHH1/95) with the 50% tissue culture infective dose (TCID50), we optimized the protease K concentration and formalin fixation time to analyze the hybridization efficiency, fluorescence intensity and repeatability. In order to measure the sensitivity of this assay, we compared it with the fluorescent antibody test (FAT) and immunohistochemical(IHC) method. Specificity of the ViewRNA ISH was tested by detecting several sub genotypes of CSFV (sub genotype 1.1, 2.1, 2.2 and 2.3) which are present in China and other normal pig infectious virus (bovine viral diarrhea virus (BVDV), porcine parvovirus (PPV), porcine pseudorabies virus (PRV) and porcine circovirusII(PCV-2). The lowest detection threshold of the ViewRNA ISH method was 10 -8 , while the sensitivity of FAT and IHC were 10 -5 and 10 -4 , respectively. The ViewRNA ISH was specific for CSFV RNA including 1.1, 2.1, 2.2 and 2.3 subtypes, meanwhile, there was no cross-reaction with negative control and other viruses including BVDV, PPV, PRV and PCV-2. Our results showed that after infection at 0.5 hpi (hours post inoculation, hpi), the CSFV RNA can be detected in nucleus and cytoplasm; during 3-9 hpi, RNA

  1. Travelers' Health: Rickettsial (Spotted and Typhus Fevers) and Related Infections (Anaplasmosis and Ehrlichiosis)

    Science.gov (United States)

    ... from eating raw infected fish. Table 3-18. Classification, primary vector, and reservoir occurrence of rickettsiae known ... within 1–2 weeks of infection include fever, headache, malaise, rash, nausea, and vomiting. Many rickettsioses are ...

  2. A single dose of the novel chimeric subunit vaccine E2-CD154 confers early full protection against classical swine fever virus.

    Science.gov (United States)

    Suárez, Marisela; Sordo, Yusmel; Prieto, Yanet; Rodríguez, María P; Méndez, Lídice; Rodríguez, Elsa M; Rodríguez-Mallon, Alina; Lorenzo, Elianet; Santana, Elaine; González, Nemecio; Naranjo, Paula; Frías, María Teresa; Carpio, Yamila; Estrada, Mario Pablo

    2017-08-03

    Classical swine fever is an economically important, highly contagious disease of swine worldwide. Subunit vaccines are a suitable alternative for the control of classical swine fever. However, such vaccines have as the main drawback the relatively long period of time required to induce a protective response, which hampers their use under outbreak conditions. In this work, a lentivirus-based gene delivery system is used to obtain a stable recombinant HEK 293 cell line for the expression of E2-CSFV antigen fused to porcine CD154 as immunostimulant molecule. The E2-CD154 chimeric protein was secreted into the medium by HEK293 cells in a concentration around 50mg/L in suspension culture conditions using spinner bottles. The E2-CD154 immunized animals were able to overcome the challenge with a high virulent CSF virus strain performed 7days after a unique dose of the vaccine without clinical manifestations of the disease. Specific anti-CSFV neutralizing antibodies and IFN-γ were induced 8days after challenge equivalent to 14days post-vaccination. The present work constitutes the first report of a subunit vaccine able to confer complete protection by the end of the first week after a single vaccination. These results suggest that the E2-CD154 antigen could be potentially used under outbreak conditions to stop CSFV spread and for eradication programs in CSF enzootic areas. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

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

    2017-06-15

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

  4. Development and inter-laboratory validation study of an improved new real-time PCR assay with internal control for detection and laboratory diagnosis of African swine fever virus.

    Science.gov (United States)

    Tignon, Marylène; Gallardo, Carmina; Iscaro, Carmen; Hutet, Evelyne; Van der Stede, Yves; Kolbasov, Denis; De Mia, Gian Mario; Le Potier, Marie-Frédérique; Bishop, Richard P; Arias, Marisa; Koenen, Frank

    2011-12-01

    A real-time polymerase chain reaction (PCR) assay for the rapid detection of African swine fever virus (ASFV), multiplexed for simultaneous detection of swine beta-actin as an endogenous control, has been developed and validated by four National Reference Laboratories of the European Union for African swine fever (ASF) including the European Union Reference Laboratory. Primers and a TaqMan(®) probe specific for ASFV were selected from conserved regions of the p72 gene. The limit of detection of the new real-time PCR assay is 5.7-57 copies of the ASFV genome. High accuracy, reproducibility and robustness of the PCR assay (CV ranging from 0.7 to 5.4%) were demonstrated both within and between laboratories using different real-time PCR equipments. The specificity of virus detection was validated using a panel of 44 isolates collected over many years in various geographical locations in Europe, Africa and America, including recent isolates from the Caucasus region, Sardinia, East and West Africa. Compared to the OIE-prescribed conventional and real-time PCR assays, the sensitivity of the new assay with internal control was improved, as demonstrated by testing 281 field samples collected in recent outbreaks and surveillance areas in Europe and Africa (170 samples) together with samples obtained through experimental infections (111 samples). This is particularly evident in the early days following experimental infection and during the course of the disease in pigs sub-clinically infected with strains of low virulence (from 35 up to 70dpi). The specificity of the assay was also confirmed on 150 samples from uninfected pigs and wild boar from ASF-free areas. Measured on the total of 431 tested samples, the positive deviation of the new assay reaches 21% or 26% compared to PCR and real-time PCR methods recommended by OIE. This improved and rigorously validated real-time PCR assay with internal control will provide a rapid, sensitive and reliable molecular tool for ASFV

  5. Short time window for transmissibility of African swine fever virus from a contaminated environment

    DEFF Research Database (Denmark)

    Olesen, A S; Lohse, L; Boklund, A.

    2018-01-01

    contaminated with excretions from ASFV-infected pigs was investigated. Following euthanasia of pigs that were infected with an isolate of ASFV from Poland (POL/2015/Podlaskie/Lindholm), healthy pigs were introduced into the pens, in which the ASFV-infected pigs had been housed. Introduction was performed at 1......, 3, 5 or 7 days, following euthanasia of the infected pig groups. Pigs, that were introduced into the contaminated environment after 1 day, developed clinical disease within 1 week, and both ASFV DNA and infectious virus were isolated from their blood. However, pigs introduced into the contaminated...

  6. Assessment of the Phenotype and Functionality of Porcine CD8 T Cell Responses following Vaccination with Live Attenuated Classical Swine Fever Virus (CSFV) and Virulent CSFV Challenge

    Science.gov (United States)

    Franzoni, Giulia; Kurkure, Nitin V.; Edgar, Daniel S.; Everett, Helen E.; Gerner, Wilhelm; Bodman-Smith, Kikki B.; Crooke, Helen R.

    2013-01-01

    Vaccination with live attenuated classical swine fever virus (CSFV) induces solid protection after only 5 days, which has been associated with virus-specific T cell gamma interferon (IFN-γ) responses. In this study, we employed flow cytometry to characterize T cell responses following vaccination and subsequent challenge infections with virulent CSFV. The CD3+ CD4− CD8hi T cell population was the first and major source of CSFV-specific IFN-γ. A proportion of these cells showed evidence for cytotoxicity, as evidenced by CD107a mobilization, and coexpressed tumor necrosis factor alpha (TNF-α). To assess the durability and recall of these responses, a second experiment was conducted where vaccinated animals were challenged with virulent CSFV after 5 days and again after a further 28 days. While virus-specific CD4 T cell (CD3+ CD4+ CD8α+) responses were detected, the dominant response was again from the CD8 T cell population, with the highest numbers of these cells being detected 14 and 7 days after the primary and secondary challenges, respectively. These CD8 T cells were further characterized as CD44hi CD62L− and expressed variable levels of CD25 and CD27, indicative of a mixed effector and effector memory phenotype. The majority of virus-specific IFN-γ+ CD8 T cells isolated at the peaks of the response after each challenge displayed CD107a on their surface, and subpopulations that coexpressed TNF-α and interleukin 2 (IL-2) were identified. While it is hoped that these data will aid the rational design and/or evaluation of next-generation marker CSFV vaccines, the novel flow cytometric panels developed should also be of value in the study of porcine T cell responses to other pathogens/vaccines. PMID:23966552

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

    Science.gov (United States)

    Graham, Simon P; Everett, Helen E; Haines, Felicity J; Johns, Helen L; Sosan, Olubukola A; Salguero, Francisco J; Clifford, Derek J; Steinbach, Falko; Drew, Trevor W; Crooke, Helen R

    2012-01-01

    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.

  8. Risk of African swine fever introduction into the European Union through transport-associated routes: returning trucks and waste from international ships and planes.

    Science.gov (United States)

    Mur, Lina; Martínez-López, Beatriz; Sánchez-Vizcaíno, José Manuel

    2012-08-30

    The uncontrolled presence of African swine fever (ASF) in Russian Federation (RF) poses a serious risk to the whole European Union (EU) pig industry. Although trade of pigs and their products is banned since the official notification in June 2007, the potential introduction of ASF virus (ASFV) may occur by other routes, which are very frequent in ASF, and more difficult to control, such as contaminated waste or infected vehicles. This study was intended to estimate the risk of ASFV introduction into the EU through three types of transport routes: returning trucks, waste from international ships and waste from international planes, which will be referred here as transport-associated routes (TAR). Since no detailed and official information was available for these routes, a semi-quantitative model based on the weighted combination of risk factors was developed to estimate the risk of ASFV introduction by TAR. Relative weights for combination of different risk factors as well as validation of the model results were obtained by an expert opinion elicitation. Model results indicate that the relative risk for ASFV introduction through TAR in most of the EU countries (16) is low, although some countries, specifically Poland and Lithuania, concentrate high levels of risk, the returning trucks route being the analyzed TAR that currently poses the highest risk for ASFV introduction into the EU. The spatial distribution of the risk of ASFV introduction varies importantly between the analyzed introduction routes. Results also highlight the need to increase the awareness and precautions for ASF prevention, particularly ensuring truck disinfection, to minimize the potential risk of entrance into the EU. This study presents the first assessment of ASF introduction into the EU through TAR. The innovative model developed here could be used in data scarce situations for estimating the relative risk associated to each EU country. This simple methodology provides a rapid and easy to

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

    Directory of Open Access Journals (Sweden)

    Simon P Graham

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

  10. Data-Driven Risk Assessment from Small Scale Epidemics: Estimation and Model Choice for Spatio-Temporal Data with Application to a Classical Swine Fever Outbreak.

    Science.gov (United States)

    Gamado, Kokouvi; Marion, Glenn; Porphyre, Thibaud

    2017-01-01

    Livestock epidemics have the potential to give rise to significant economic, welfare, and social costs. Incursions of emerging and re-emerging pathogens may lead to small and repeated outbreaks. Analysis of the resulting data is statistically challenging but can inform disease preparedness reducing potential future losses. We present a framework for spatial risk assessment of disease incursions based on data from small localized historic outbreaks. We focus on between-farm spread of livestock pathogens and illustrate our methods by application to data on the small outbreak of Classical Swine Fever (CSF) that occurred in 2000 in East Anglia, UK. We apply models based on continuous time semi-Markov processes, using data-augmentation Markov Chain Monte Carlo techniques within a Bayesian framework to infer disease dynamics and detection from incompletely observed outbreaks. The spatial transmission kernel describing pathogen spread between farms, and the distribution of times between infection and detection, is estimated alongside unobserved exposure times. Our results demonstrate inference is reliable even for relatively small outbreaks when the data-generating model is known. However, associated risk assessments depend strongly on the form of the fitted transmission kernel. Therefore, for real applications, methods are needed to select the most appropriate model in light of the data. We assess standard Deviance Information Criteria (DIC) model selection tools and recently introduced latent residual methods of model assessment, in selecting the functional form of the spatial transmission kernel. These methods are applied to the CSF data, and tested in simulated scenarios which represent field data, but assume the data generation mechanism is known. Analysis of simulated scenarios shows that latent residual methods enable reliable selection of the transmission kernel even for small outbreaks whereas the DIC is less reliable. Moreover, compared with DIC, model choice

  11. The influence of diet on the development of swine dysentery upon experimental infection

    DEFF Research Database (Denmark)

    Lindecrona, R.H.; Jensen, Tim Kåre; Jensen, B.B.

    2003-01-01

    The purpose of the present study was to evaluate the effect of fermented liquid food (FLF) and the addition of lactic acid to a diet based on wheat and barley on the development of swine dysentery in pigs experimentally infected with a Danish field isolate of Brachyspira hyodysenteriae. Furthermore...... and sugar-beet pulp. The experiment was designed as a randomized-block trial and was performed in triplicate including a total of 192 pigs. After feeding the diets for 2 weeks, six pigs in each group were challenged orally with B. hyodysenteriae and observed for another 4 weeks. After challenge, swine...

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

    Science.gov (United States)

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

    2016-03-01

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

  13. Differentiated swine airway epithelial cell cultures for the investigation of influenza A virus infection and replication

    OpenAIRE

    Bateman, Allen C.; Karasin, Alexander I.; Olsen, Christopher W.

    2012-01-01

    Please cite this paper as: Bateman et al. (2013) Differentiated swine airway epithelial cell cultures for the investigation of influenza A virus infection and replication. Influenza and Other Respiratory Viruses 7(2) 139–150. Background  Differentiated human airway epithelial cell cultures have been utilized to investigate cystic fibrosis, wound healing, and characteristics of viral infections. These cultures, grown at an air–liquid interface (ALI) in media with defined hormones and growth fa...

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

    Science.gov (United States)

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

    2016-03-01

    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. 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. 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. 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.

  15. Evaluation of Oral Bait Vaccine Efficacy Against Classical Swine Fever in Village Backyard Pig Farms in Bhutan.

    Science.gov (United States)

    Monger, V R; Stegeman, J A; Dukpa, K; Gurung, R B; Loeffen, W L A

    2016-12-01

    Control and eradication of classical swine fever (CSF) in countries with a high proportion of backyard holdings is a challenge. Conventional attenuated Chinese C-strain vaccines, though safe and effective, are difficult to use in backyard farms due to various practical reasons. The aim of this study was to evaluate the efficacy of the CSF oral bait vaccine in village backyard pig farms and to assess the farmers' knowledge on CSF and motivation on using oral vaccines. The pigs were fed the bait by the farmers themselves; one bait was given on day 0, followed by second bait on the next day. Seventy-three per cent (140 of 193 pigs) of vaccinated pigs had either a slight (2-fold-3-fold; 60 pigs) or significant (at least 4-fold; 80 pigs) increase of the antibody titre against CSFV. A significant increase of the antibody titres was mainly observed in pigs with no pre-vaccination titre (OR = 12, 95% CI = 4-40). The number of pigs with protective antibody titres (≥40) rose from 47 (24%) to 115 (60%) following vaccination. Only 30% of the farmers claimed to be familiar with CSF, although clinical signs they mentioned were rather unspecific and could relate to many other pig diseases. Most of the farmers claimed to be motivated to use oral vaccines if made available. The oral vaccine could be a substitute for the conventional attenuated CSF vaccines in areas where it is logistically difficult for veterinarians to visit. It may therefore be a useful tool to combat endemic CSF disease in regions where the disease continues to have a serious impact on the backyard farmers who depend on pig farming for their sustenance and livelihoods. © 2015 Blackwell Verlag GmbH.

  16. 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. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. 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. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights

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

    Science.gov (United States)

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

    2015-09-01

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

  19. Development of a reverse-transcription polymerase chain reaction assay with fluorogenic probes to discriminate Korean wild-type and vaccine isolates of Classical swine fever virus

    OpenAIRE

    Cho, Ho-Seong; Park, Suk-Jun; Park, Nam-Yong

    2006-01-01

    A 1-step reverse-transcription polymerase chain reaction (RT-PCR) assay using TaqMan minor-groove-binding (MGB) probes was developed to distinguish between vaccine-type and wild-type strains of Classical swine fever virus (CSFV) in Korea. Because attenuated Korean LOM strains have been used in animal vaccination in Korea for some time but CSF remains a serious problem, there was a need for a practical approach to differentiating vaccine and field strains. We examined the fluorescence of 5 vac...

  20. Investigation of a possible yellow fever epidemic and serosurvey for flavivirus infections in northern Cameroon, 1984

    OpenAIRE

    Tsai, T. F.; Lazuick, J. S.; Ngah, R. W.; Mafiamba, P. C.; Quincke, G.; Monath, T. P.

    1987-01-01

    A cluster of fatal hepatitis cases in northern Cameroon in 1984 stimulated a field investigation to rule out an epidemic of yellow fever. A serosurvey of villages in the extreme north of the country, in a Sudan savanna (SS) phytogeographical zone, disclosed no evidence of recent yellow fever infection. However, further south, in a Guinea savanna (GS) phytogeographical zone, serological evidence was found of endemic yellow fever virus transmission. The results indicate a potential for epidemic...

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

    Directory of Open Access Journals (Sweden)

    Massimo Amadori

    2017-04-01

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

  2. Urinary tract infections and post-operative fever in percutaneous nephrolithotomy

    DEFF Research Database (Denmark)

    Gutierrez, Jorge; Smith, Arthur; Geavlete, Petrisor

    2013-01-01

    of systemic infection. CONCLUSIONS: Approximately 10% of PCNL-treated patients developed fever in the post-operative period despite receiving antibiotic prophylaxis. Risk of post-operative fever increased in the presence of a positive urine bacterial culture, diabetes, staghorn calculi, and a pre...

  3. Screening of blood donors for chronic Coxiella burnetii infection after large Q fever outbreaks

    NARCIS (Netherlands)

    Slot, Ed; Hogema, Boris M.; Molier, Michel; Zaaijer, Hans L.

    2014-01-01

    The Netherlands experienced major Q fever outbreaks from 2007 through 2009. An increasing number of human chronic Q fever cases has been reported in the affected area. Blood donors unaware of chronic Coxiella burnetii infection might be infectious for transfusion recipients. Local blood donations

  4. Co-infection of malaria and typhoid fever in a tropical community ...

    African Journals Online (AJOL)

    A study was carried out on patients clinically diagnosed of malaria or typhoid or both, at Nnewi Anambra State, Nigeria, to investigate the level of association between malaria and typhoid fever infections. The stool culture was used as an additional diagnostic test for typhod fever. The study indicated that out of 256 patients, ...

  5. Mayaro fever in an HIV-infected patient suspected of having Chikungunya fever.

    Science.gov (United States)

    Estofolete, Cássia Fernanda; Mota, Mânlio Tasso Oliveira; Vedovello, Danila; Góngora, Delzi Vinha Nunes de; Maia, Irineu Luiz; Nogueira, Maurício Lacerda

    2016-01-01

    Arboviruses impose a serious threat to public health services. We report a case of a patient returning from a work trip to the Amazon basin with myalgia, arthralgia, fever, and headache. During this travel, the patient visited riverside communities. Both dengue and Chikungunya fevers were first suspected, tested for, and excluded. Mayaro fever was then confirmed by reverse transcription polymerase chain reaction followed by next-generation sequencing and phylogenetic reconstruction. The increased awareness of physicians and consequent detection of Mayaro virus in this case was only possible due a previous surveillance program with specific health personnel training about these neglected arboviruses.

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

    DEFF Research Database (Denmark)

    Lohse, Louise; Nielsen, Jens; Uttenthal, Åse

    2012-01-01

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

  7. Investigation of a possible yellow fever epidemic and serosurvey for flavivirus infections in northern Cameroon, 1984.

    Science.gov (United States)

    Tsai, T F; Lazuick, J S; Ngah, R W; Mafiamba, P C; Quincke, G; Monath, T P

    1987-01-01

    A cluster of fatal hepatitis cases in northern Cameroon in 1984 stimulated a field investigation to rule out an epidemic of yellow fever. A serosurvey of villages in the extreme north of the country, in a Sudan savanna (SS) phytogeographical zone, disclosed no evidence of recent yellow fever infection. However, further south, in a Guinea savanna (GS) phytogeographical zone, serological evidence was found of endemic yellow fever virus transmission. The results indicate a potential for epidemic spread of yellow fever virus from the southern GS zone to the nothern SS zone of Cameroon, where immunity in the population was low.

  8. Analysis of the acute-phase protein response in pigs to clinical and subclinical infection with H3N2 swine influenza virus.

    Science.gov (United States)

    Pomorska-Mól, Małgorzata; Kwit, Krzysztof; Pejsak, Zygmunt; Markowska-Daniel, Iwona

    2014-03-01

    Swine influenza (SI) is a contagious, important respiratory disease. Diagnosis of SI is based on the clinical signs, confirmed by the detection of viral RNA or specific antibodies. However, the infection is much more frequent than the disease. The aim of study was to investigate the kinetics of acute-phase protein (APP) response during subclinical and clinical influenza in pigs. The utility of APP measurements in identification of infected animals was also evaluated. Twenty-eight piglets were used. C-reactive protein (CRP), haptoglobin (Hp), serum amyloid A (SAA) and pig major acute-phase protein (Pig-MAP) concentrations in serum were measured using commercial ELISAs. No relevant clinical signs were observed in intranasally infected pigs. In contrast, coughing, nasal discharge, and fever were observed in pigs infected intratracheally. All infected pigs exhibited specific antibodies in the serum at 10 dpi, and viral shedding was confirmed. The concentrations of CRP, Hp and SAA were significantly increased after infection. The level of Pig-MAP remained constant during subclinical and clinical infection. The concentrations of CRP, Hp and SAA were higher in pigs with clinical disease. Although not specific, strategic APP measurements may reveal ongoing clinical and subclinical infection. A close relationship between the magnitude of serum APP response with the severity of disease, providing an objective tool for validation the severity of infection. The maximum concentration of SAA in serum was closely correlated with lung score and makes this APP potential indicator for disease progress or estimation of treatment strategy.

  9. Immunization of African Indigenous Pigs with Attenuated Genotype I African Swine Fever Virus OURT88/3 Induces Protection Against Challenge with Virulent Strains of Genotype I.

    Science.gov (United States)

    Mulumba-Mfumu, L K; Goatley, L C; Saegerman, C; Takamatsu, H-H; Dixon, L K

    2016-10-01

    The attenuated African swine fever virus genotype I strain OURT88/3 has previously been shown to induce protection of European breeds of domestic pigs against challenge with virulent isolates. To determine whether protective immune responses could also be induced in indigenous breeds of pigs from the Kinshassa region in Democratic Republic of Congo, we immunized a group of eight pigs with OURT88/3 strain and challenged the pigs 3 weeks later with virulent genotype I strain OURT88/1. Four of the pigs were protected against challenge. Three of the eight pigs died from African swine fever virus and a fourth from an unknown cause. The remaining four pigs all survived challenge with a recent virulent genotype I strain from the Democratic Republic of Congo, DRC 085/10. Control groups of non-immune pigs challenged with OURT88/1 or DRC 085/10 developed signs of acute ASFV as expected and had high levels of virus genome in blood. © 2015 Blackwell Verlag GmbH.

  10. 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...... as a distribution (0.0042:0.0083; 0.05), and the within-herd and between-herd design prevalence were set to 0.05 and 0.01, respectively. If 50 and 75% of the test results from exported or slaughtered sows and boars were simulated to be removed at random, while the blood samples from boar stations were kept constant...

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

    Science.gov (United States)

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

    2018-02-01

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

  12. 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. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  13. Relevant Measures to Prevent the Spread of African Swine Fever in the European Union Domestic Pig Sector

    Directory of Open Access Journals (Sweden)

    Cristina Jurado

    2018-04-01

    Full Text Available During the past decade, African swine fever (ASF has spread from the Caucasus region to eastern European Union countries affecting domestic pig and wild boar populations. In order to avert ASF spread, mitigation measures targeting both populations have been established. However, despite these efforts, ASF has been reported in thirteen different countries (Georgia, Azerbaijan, Armenia, the Russian Federation, Ukraine, Belarus, Estonia, Latvia, Lithuania, Poland, Moldova, Czech Republic, and Romania. In the absence of an effective vaccine or treatment to ASF, introduction and spread of ASF onto domestic pig farms can only be prevented by strict compliance to control measures. This study systematically reviewed available measures to prevent the spread of ASF in the EU domestic pig sector distinguishing between commercial, non-commercial, and outdoor farms. The search was performed in PubMed and using a common browser. A total of 52 documents were selected for the final review process, which included scientific articles, reports, EU documents and official recommendations, among others. From this literature review, 37 measures were identified as preventive measures for the introduction and spread of ASF. Subsequently, these measures were assessed by ASF experts for their relevance in the mitigation of ASF spread on the three mentioned types of farms. All experts agreed that some of the important preventive measures for all three types of farms were: the identification of animals and farm records; strict enforcement of the ban on swill feeding; and containment of pigs, so as to not allow direct or indirect pig–pig and/or pig–wild boar contacts. Other important preventive measures for all farms were education of farmers, workers, and operators; no contact between farmers and farm staff and external pigs; appropriate removal of carcasses, slaughter residues, and food waste; proper disposal of manure and dead animals, and abstaining from hunting

  14. An investigation of classical swine fever virus seroprevalence and risk factors in pigs in East Nusa Tenggara, eastern Indonesia.

    Science.gov (United States)

    Sawford, Kate; Geong, Maria; Bulu, Petrus M; Drayton, Emily; Mahardika, Gusti N K; Leslie, Edwina E C; Robertson, Ian; Gde Putra, Anak Agung; Toribio, Jenny-Ann L M L

    2015-05-01

    Classical swine fever virus (CSFV) is a highly infectious disease of pigs. It has had significant impacts on East Nusa Tenggara, eastern Indonesia since its introduction in 1997. In spite of its importance to this region, little is known about its seroprevalence and distribution, and pig-level and farmer-level factors that may have an impact on the serological status of an individual pig. To address this knowledge deficit, a cross-sectional seroprevalence survey was conducted in 2010 involving 2160 pigs and 805 farmers from four islands in the region. Farmer questionnaires and pig record forms were used to collect data about the farmers and pigs surveyed. Blood was collected from each pig to determine its CSFV serological status. Apparent and true prevalence were calculated for each island, district, subdistrict, and village surveyed. CSFV serological status was used as an outcome variable in mixed effects logistic regression analyses. Overall true CSFV seroprevalence was estimated at 17.5% (lower CI 16.0%; upper CI 19.5%). Seroprevalence estimates varied widely across the islands, districts, subdistricts, and villages. Manggarai Barat, a district on the western end of Flores Island, contained pigs that were positive for antibody to CSFV. This result was unexpected, as no clinical cases had been reported in this area. Older pigs and pigs that had been vaccinated for CSFV were more likely to test positive for antibody to CSFV. 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 2% of the variation explained by pig age and pig CSFV vaccination status. In this study we documented the seroprevalence of CSFV across four islands in East Nusa Tenggara, eastern Indonesia. We also identified risk factors for the presence of antibody to CSFV. Further investigation is needed to understand why clinical CSFV has not been reported on the western end of Flores Island

  15. 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

    NARCIS (Netherlands)

    Asseldonk, van M.A.P.M.; Jong, de M.C.M.; 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

  16. 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.

    NARCIS (Netherlands)

    Hoffmann, B.; Blome, S.; Bonulauri, P.; Fernández-Pinero, J.; Greiser-Wilke, I.; Haegeman, A.; Isaksson, M.; Koenen, F.; Leblanc, N.; Leifer, I.; Potier, Le M.F.; Loeffen, W.; Rasmussen, T.B.; Stadejek, T.; Stahl, K.; Tignon, M.; Uttenthal, A.; Poel, van der W.H.M.

    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

  17. Transmission dynamics of hepatitis E among swine: potential impact upon human infection

    Directory of Open Access Journals (Sweden)

    Nishiura Hiroshi

    2007-05-01

    Full Text Available Abstract Background Hepatitis E virus (HEV infection is a zoonosis for which pigs play a role as a reservoir. In Japan, the infection has been enzootic in swine. Clarifying the detailed mechanisms of transmission within farms is required in order to facilitate an understanding of the age-specific patterns of infection, especially just prior to slaughter. Results Here we reanalyze a large-scale seroprevalence survey dataset from Japanese pig farms to estimate the force of infection. The forces of infection of swine HEV were estimated to be 3.45 (95% confidence interval: 3.17, 3.75, 2.68 (2.28, 3.14 and 3.11 (2.76, 3.50 [×10-2 per day] in Hokkaido, Honshu and Kyushu, respectively. The estimates with our model assumptions indicated that the average ages at infection ranged from 59.0–67.3 days and that the basic reproduction number, R0, was in the order of 4.02–5.17. Sensitivity analyses of age-specific incidence at different forces of infection revealed that a decline in the force of infection would elevate the age at infection and could increase the number of virus-excreting pigs at the age of 180 days. Conclusion Although our estimates imply that more than 95% of pigs are infected before the age of 150 days, the model shows that a decline in the force of infection could increase the risk of pig-to-human transmission. If the force of infection started to decline, it might be necessary to implement radical countermeasures (e.g. separation of uninfected pigs from infected herds beginning from the end of the suckling stage to minimize the number of virus-positive pigs at the finishing stage.

  18. Management Of Fever And Suspected Infection In Pediatric Patients With Central Venous Catheters.

    Science.gov (United States)

    Brennan, Courtney; Wang, Vincent J

    2015-12-01

    The use of indwelling central venous catheters is essential for pediatric patients who require hemodialysis, parenteral nutrition, chemotherapy, or other medications. Fever is a common chief complaint in the emergency department, and fever in a patient with a central venous catheter may be related to a common cause of fever, or it may be due to a catheter-associated bloodstream infection. Catheter-associated bloodstream infections may also lead to additional complications such as sepsis, septic shock, or septic complications including suppurative thrombophlebitis, endocarditis, osteomyelitis, septic emboli, and abscesses. Early resuscitation as well as timely and appropriate antibiotic therapy have been shown to improve outcomes. This issue focuses on the approach to fever in pediatric patients with central venous catheters and the management and disposition of patients with possible catheter-associated bloodstream infections.

  19. Transcriptional profiling of swine lung tissue after experimental infection with Actinobacillus pleuropneumoniae.

    Science.gov (United States)

    Zuo, Zhicai; Cui, Hengmin; Li, Mingzhou; Peng, Xi; Zhu, Ling; Zhang, Ming; Ma, Jideng; Xu, Zhiwen; Gan, Meng; Deng, Junliang; Li, Xuewei; Fang, Jing

    2013-05-21

    Porcine pleuropneumonia is a highly contagious respiratory disease that causes great economic losses worldwide. In this study, we aimed to explore the underlying relationship between infection and injury by investigation of the whole porcine genome expression profiles of swine lung tissues post-inoculated with experimentally Actinobacillus pleuropneumoniae. Expression profiling experiments of the control group and the treatment group were conducted using a commercially available Agilent Porcine Genechip including 43,603 probe sets. Microarray analysis was conducted on profiles of lung from challenged versus non-challenged swine. We found 11,929 transcripts, identified as differentially expressed at the p ≤0.01 level. There were 1188 genes annotated as swine genes in the GenBank Data Base. GO term analysis identified a total of 89 biological process categories, 82 cellular components and 182 molecular functions that were significantly affected, and at least 27 biological process categories that were related to the host immune response. Gene set enrichment analysis identified 13 pathways that were significantly associated with host response. Many proinflammatory-inflammatory cytokines were activated and involved in the regulation of the host defense response at the site of inflammation; while the cytokines involved in regulation of the host immune response were suppressed. All changes of genes and pathways of induced or repressed expression not only led to a decrease in antigenic peptides presented to T lymphocytes by APCs via the MHC and alleviated immune response injury induced by infection, but also stimulated stem cells to produce granulocytes (neutrophils, eosinophils, and basophils) and monocyte, and promote neutrophils and macrophages to phagocytose bacterial and foreign antigen at the site of inflammation. The defense function of swine infection with Actinobacillus pleuropneumoniae was improved, while its immune function was decreased.

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

    Science.gov (United States)

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

    2017-05-01

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

  1. 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

  2. The influence of diet on the development of swine dysentery upon experimental infection

    DEFF Research Database (Denmark)

    Lindecrona, R.H.; Jensen, Tim Kåre; Jensen, B.B.

    2003-01-01

    , to confirm if low non-starch polysaccharide (NSP)-containing diets reduce swine dysentery the effect of different dietary levels of NSP and resistant starch (RS) was evaluated. These diets were based on cooked rice and animal protein, cooked rice and potato starch, cooked rice and wheat bran, or cooked rice......The purpose of the present study was to evaluate the effect of fermented liquid food (FLF) and the addition of lactic acid to a diet based on wheat and barley on the development of swine dysentery in pigs experimentally infected with a Danish field isolate of Brachyspira hyodysenteriae. Furthermore...... dysentery was observed in all feeding groups. The incidence of disease varied between 94% (rice/wheat bran) and 44% (FLF). The effect of diet on faecal shedding of B. hyodysenteriae was statistically significant (P...

  3. Correlation of Physical Exam Findings with Fever in Patients with Skin and Soft Tissue Infections.

    Science.gov (United States)

    Mongelluzzo, Jillian; Tu, Brian; Grimes, Barbara; Ziyeh, Sharvina; Fortman, Jonathan; Neilson, Jersey; Rodriguez, Robert M

    2017-04-01

    The objectives of this study were to determine the prevalence of fever in adult ED patients with skin and soft tissue infections (SSTI) and to determine which, if any, physical exam, radiograph and laboratory test findings were associated with fever. We conducted a prospective, observational study at an urban county trauma center of adults who presented to the ED for evaluation of suspected SSTI. ED providers measured area of erythema and induration using a tape measure, and completed data sheets indicating comorbid conditions and the presence or absence of physical exam findings. Fever was defined as any recorded temperature ≥ 38°C during the first six hours of ED evaluation. Of the 734 patients enrolled, 96 (13.1%) had fever. Physical and laboratory exam findings associated with the presence of a fever in multivariable logistic regression were the area of erythema, particularly the largest quartile of area of erythema, 144 - 5,000 cm 2 , (odd ratio [OR] = 2.9; 95% confidence interval [CI] [1.6 - 5.2]) and leukocytosis (OR = 4.4, 95% CI [2.7 - 7.0]). Bullae, necrosis, streaks, adenopathy, and bone involvement on imaging were not associated with fever. Fever is uncommon in patients presenting to the ED for evaluation of suspected SSTI. Area of erythema and leukocytosis were associated with fever and should be considered in future decision rules for the evaluation and treatment of SSTI.

  4. Clinical predictors of dengue fever co-infected with leptospirosis among patients admitted for dengue fever - a pilot study.

    Science.gov (United States)

    Suppiah, Jeyanthi; Chan, Shie-Yien; Ng, Min-Wern; Khaw, Yam-Sim; Ching, Siew-Mooi; Mat-Nor, Lailatul Akmar; Ahmad-Najimudin, Naematul Ain; Chee, Hui-Yee

    2017-06-28

    Dengue and leptospirosis infections are currently two major endemics in Malaysia. Owing to the overlapping clinical symptoms between both the diseases, frequent misdiagnosis and confusion of treatment occurs. As a solution, the present work initiated a pilot study to investigate the incidence related to co-infection of leptospirosis among dengue patients. This enables the identification of more parameters to predict the occurrence of co-infection. Two hundred sixty eight serum specimens collected from patients that were diagnosed for dengue fever were confirmed for dengue virus serotyping by real-time polymerase chain reaction. Clinical, laboratory and demographic data were extracted from the hospital database to identify patients with confirmed leptospirosis infection among the dengue patients. Thus, frequency of co-infection was calculated and association of the dataset with dengue-leptospirosis co-infection was statistically determined. The frequency of dengue co-infection with leptospirosis was 4.1%. Male has higher preponderance of developing the co-infection and end result of shock as clinical symptom is more likely present among co-infected cases. It is also noteworthy that, DENV 1 is the common dengue serotype among all cases identified as dengue-leptospirosis co-infection in this study. The increasing incidence of leptospirosis among dengue infected patients has posed the need to precisely identify the presence of co-infection for the betterment of treatment without mistakenly ruling out either one of them. Thus, anticipating the possible clinical symptoms and laboratory results of dengue-leptospirosis co-infection is essential.

  5. 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. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. The costs of preventive activities for exotic contagious diseases - A Danish case study of foot and mouth disease and swine fever

    DEFF Research Database (Denmark)

    Denver, Sigrid; Alban, Lis; Boklund, Anette

    2016-01-01

    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......The present paper provides an overview of the costs of preventive activities, currently undertaken in Denmark, related to foot and mouth disease (FMD) and classical and African swine fever (SF). Only costs held between outbreaks were included. Costs were divided into public costs and costs paid...... in a group of experts from universities, industry, and public authorities. The costs of each preventive activity were related to the type of activity, the number of times the activity was carried out and the share of costs that could be associated with FMD or SF. Uncertainty about parameters was incorporated...

  7. Relapsing fever

    Science.gov (United States)

    ... It is characterized by repeated episodes of fever. Causes Relapsing fever is an infection caused by several species of ... death of very large numbers of borrelia bacteria causes shock) Weakness Widespread bleeding ... health care provider right away if you develop a fever after returning from a trip. Possible infections need ...

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

    Science.gov (United States)

    Lubaba, Caesar H.; Kajihara, Masahiro; Mataa, Liywalii; Chambaro, Herman Moses; Sinkala, Yona; Munjita, Samuel Munalula; Nalubamba, King Shimumbo; Samui, Kenny; Pandey, Girja Shanker; Takada, Ayato; Mweene, Aaron S.

    2017-01-01

    African swine fever (ASF) is a highly contagious and deadly viral hemorrhagic disease of swine. In Zambia, ASF was first reported in 1912 in Eastern Province and is currently believed to be endemic in that province only. Strict quarantine measures implemented at the Luangwa River Bridge, the only surface outlet from Eastern Province, appeared to be successful in restricting the disease. However, in 1989, an outbreak occurred for the first time outside the endemic province. Sporadic outbreaks have since occurred almost throughout the country. These events have brought into acute focus our limited understanding of the epidemiology of ASF in Zambia. Here, we review the epidemiology of the disease in areas considered nonendemic from 1989 to 2015. Comprehensive sequence analysis conducted on genetic data of ASF viruses (ASFVs) detected in domestic pigs revealed that p72 genotypes I, II, VIII and XIV have been involved in causing ASF outbreaks in swine during the study period. With the exception of the 1989 outbreak, we found no concrete evidence of dissemination of ASFVs from Eastern Province to other parts of the country. Our analyses revealed a complex epidemiology of the disease with a possibility of sylvatic cycle involvement. Trade and/or movement of pigs and their products, both within and across international borders, appear to have been the major factor in ASFV dissemination. Since ASFVs with the potential to cause countrywide and possibly regional outbreaks, could emerge from “nonendemic regions”, the current ASF control policy in Zambia requires a dramatic shift to ensure a more sustainable pig industry. PMID:28832525

  9. 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

    2015-11-27

    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.

  10. 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.

  11. Identification of swine influenza A virus and Stenotrophomonas maltophilia co-infection in Chinese pigs

    Directory of Open Access Journals (Sweden)

    Hou Dongjun

    2012-08-01

    Full Text Available Abstract Background Influenza virus virulence can be exacerbated by bacterial co-infections. Swine influenza virus (SIV infection together with some bacteria is found to enhance pathogenicity. Methods SIV-positive samples suspected of containing bacteria were used for bacterial isolation and identification. Antimicrobial susceptibility testing was performed by disc diffusion methods. To investigate the interaction of SIV and the bacteria in vitro, guinea pigs were used as mammalian hosts to determine the effect on viral susceptibility and transmissibility. Differences in viral titers between groups were compared using Student’s t-test. Results During surveillance for SIV in China from 2006 to 2009, seven isolates (24.14% of 29 influenza A viruses were co-isolated with Stenotrophomonas maltophilia from nasal and tracheal swab samples of pigs. Antimicrobial susceptibility testing showed that the bacteria possessed a high level of resistance towards clinically used antibiotics. To investigate the interaction between these two microorganisms in influencing viral susceptibility and transmission in humans, guinea pigs were used as an infection model. Animals were inoculated with SIV or S. maltophilia alone or co-infected with SIV and S. maltophilia. The results showed that although no transmission among guinea pigs was observed, virus–bacteria co-infections resulted in higher virus titers in nasal washes and trachea and a longer virus shedding period. Conclusions This is the first report of influenza virus co-infection with S. maltophilia in the Chinese swine population. Increased replication of virus by co-infection with multidrug resistant bacteria might increase the infection rate of SIV in humans. The control of S. maltophilia in clinics will contribute to reducing the spread of SIV in pigs and humans.

  12. Could be the swine responsible of transmission to the humans of Dientamoeba fragilis infection?

    Directory of Open Access Journals (Sweden)

    Daniele Crotti

    2011-03-01

    Full Text Available Dientamoeba fragilis, atypical protozoon because “flagellate without flagella” but amoeba-like, of whom we know only the trophozoitic stage (an so its brittleness outside intestinal tract, is a frequent responsible of intestinal human infections, worldwide, and some authors relate that D. fragilis is the most frequent protozoon and parasite that can infects humans. Actually we don’t know a sure potential “reservoir” in animals who are strictly in contact with humans, and it is difficult to understand its epidemiological chain, otherwise the transmissions to humans and from humans to humans. For all these reasons we performed another study on subjects of swine breedings, and among people who work in these breedings, that are in direct contact or not with pigs. Using standardized methodologies, we analyzed 224 faecal specimens of swine and 15 human specimens.We use for identification of D. fragilis the Giemsa stain.These were the results: D. fragilis was observed in 50.9% of pigs and 20% among humans (30% in workers strictly in contact with breedings and pigs, 0% in familiars or other without a closed contact with swines. Other commensal protozoa were observed with variable associations, but in this article we want to analyze the possible transmission from this pigs to humans (and for us this protozoon is undoubtedly a “reservoir” of D. fragilis for humans, and underline two aspects: for the research of this protozoon, standard procedures area mandatory, with a permanent stain, as Giemsa stain, is necessary, and in all humans with various intestinal infections or troubles, particularly “irritable bowel syndrome” (or similar ones, the specimens must be analyzed for D. fragilis. At least we think that in the near future molecular studies are important for confirming this our observations, and for verifying eventual and probable differences inside genotypes of this very suggestive protozoon, that until now present not rarely

  13. Occurrence of infection by Toxoplasma gondii in slaughtered swine in the northwestern region of Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Hannah Lia Ettiene Peruch Lemos dos Santos

    2015-07-01

    Full Text Available This study aimed to determine the prevalence of Toxoplasma gondii in swine slaughtered in Iporã, Northwest Paraná state. Blood samples were obtained from 500 finishing swine. All animals were raised under intensive farming; the blood samples were analyzed using the immunofluorescence antibody test (IFAT. Animals with titers of ?64 were considered positive for T. gondii infection. Of the tested samples, 63 (12.6% were positive by IFAT; 58 (92.06% of these showed titers of 64 (4.7%, with titers 256 and two (3.1% titers of 1024. These pigs might be considered a source of T. gondii infection for humans

  14. Predictive value of fever following arthroplasty in diagnosing an early infection.

    Science.gov (United States)

    Ascione, Tiziana; Balato, Giovanni; Boccia, Giovanni; De Caro, Francesco

    2017-03-01

    Postoperative fever after orthopaedic surgery is a controversial clinical problem in daily practice because damaged tissue due to surgical intervention can induce the production of proinflammatory cytokines responsible of the systemic inflammatory response syndrome. No current diagnostic marker can differentiate with sufficient accuracy infectious from non-infectious fever in patients undergoing orthopaedic surgery, but early diagnosis of postoperative orthopaedic infections is important in order to rapidly initiate adequate antimicrobial therapy. Review of clinical trials on fever did not establish the parameters reporting sufficient diagnostic accuracy. Blood cultures, white blood-cent count, erythrocyte sedimentation rate and C-reactive protein have low specificity. Procalcitonin and IL-6 can be helpful diagnostic markers supporting clinical findings. An algorithm for evaluation of fever in orthopaedic surgery may be a helpful tool.

  15. Fever and infections in pregnancy and risk of attention deficit/hyperactivity disorder in the offspring

    DEFF Research Database (Denmark)

    Dreier, Julie Werenberg; Andersen, Anne-Marie Nybo; Hvolby, Allan

    2016-01-01

    Background: Fever and infections are common events during pregnancy, and have been shown to be associated with neurodevelopmental impairment in the offspring. The evidence in relation to attention deficit/hyperactivity disorder (ADHD) is, however, nonexistent for fever and limited for infections....... The aim of this study was therefore to investigate the impact of these exposures on the occurrence of ADHD in the offspring, considering gestational timing as well as intensity of exposure. Methods: The study was conducted within the Danish National Birth Cohort, using data on 89,146 pregnancies enrolled...

  16. Lack of evidence of porcine reproductive and respiratory syndrome virus (PRRSV infection in domestic swine in Brazil

    Directory of Open Access Journals (Sweden)

    Ciacci-Zanella Janice Reis

    2004-01-01

    Full Text Available This report describes the first prevalence of antibodies and experimental inoculation of suspected samples of porcine reproductive and respiratory syndrome virus (PRRSV from ELISA positive pigs from swine herds in Brazil. Based on the hypothesis that this agent is present in swine herds worldwide, the objective of this work was to establish a diagnostic methodology and to investigate the occurrence of PRRSV in Brazilian swine herds. Fifty-four swine herds, the total number which imported genetic material (live pigs or swine semen from countries where PRRS was endemic from 1990 to December 2000, from eight Brazilian States all included in this study. The sampling used was such as to detect a prevalence of infection of 5%, with a confidence level of 95%. A total of 3785 serum samples were tested for PRRSV antibodies by ELISA. Following the ELISA test, which was performed with two different commercial kits, all serum positive pigs were retested, examined and additional materials were collected. Viral isolation in permissive tissue culture cells and swine bioassays were performed. Additionally, reverse transcriptase polymerase chain reaction (RT-PCR and nested RT-PCR were also performed. We could not demonstrate the presence of PRRSV or RNA of PRRSV by viral isolation or RT-PCR (or nested RT-PCR, respectively in all of the analyzed samples. Furthermore, the pigs inoculated with PRRSV suspicion samples did not seroconvert nor produce characteristic PRRS lesions in the swine bioassay. Thus, our results indicate no evidence of PRRSV in the samples analyzed from swine herds in this study.

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

    Science.gov (United States)

    Abrao, Emiliana Pereira; da Fonseca, Benedito Antônio Lopes

    2016-02-01

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

  18. Bronchiolitis Obliterans Organizing Pneumonia in Swine Associated with Porcine Circovirus Type 2 Infection

    Directory of Open Access Journals (Sweden)

    Ching-Chang Cheng

    2011-01-01

    Full Text Available Bronchiolitis obliterans organizing pneumonia (BOOP is a chronic respiratory disease. Although the pathogenesis of BOOP is still incompletely understood, BOOP is responsive to steroids and has a good prognosis. In our five pigs with chronic postweaning multisystemic wasting syndrome (PMWS, typical BOOP lesions were revealed. All five porcine lungs showed typical intraluminal plugs, and porcine circovirus type 2 (PCV2 was identified. They also exhibited similar pathologic findings such as proliferation of type II pneumocytes and myofibroblasts (MFBs, extracellular collagen matrix (ECM deposition, and fragmentation of elastic fibers. MFBs migration correlative molecules, for instance, gelatinase A, B and osteopontin, appeared strongly in the progressing marginal area of polypoid intraluminal plugs of fibrotic lesion. These molecules colocalized with the active MFBs. Both gelatinase activity and intercellular level of active MFBs were significantly increased (<.05. Porcine chronic bronchopneumonia leads to BOOP and it is associated with PCV2 persistent infection. Swine BOOP demonstrates similar cellular constituents with human BOOP. Perhaps their molecular mechanisms of pathogenesis operate in a similar way. Thus we infer that the swine BOOP can be considered as a potential animal model for human BOOP associated with natural viral infection. Moreover, it is more convenient to obtain samples.

  19. Virological and serological study of human infection with swine influenza A H1N1 virus in China.

    Science.gov (United States)

    Zu, Rongqiang; Dong, Libo; Qi, Xian; Wang, Dayan; Zou, Shumei; Bai, Tian; Li, Ming; Li, Xiaodan; Zhao, Xiang; Xu, Cuiling; Huo, Xiang; Xiang, Nijuan; Yang, Shuai; Li, Zi; Xu, Zhen; Wang, Hua; Shu, Yuelong

    2013-11-01

    Pigs are considered to be "mixing vessels" for the emergence of influenza viruses with pandemic potential. 2009 Pandemic Influenza H1N1 further proved this hypothesis, and raised the needs for risk assessment of human cases caused by swine influenza virus. A field investigation was conducted after a case identified with infection of European avian-like swine influenza H1N1 virus. The diagnosis was confirmed by real-time PCR, virus isolation, whole genome sequencing and serological assays. Samples from local pigs and close contacts were tested to identify the source of infection and route of transmission. The virus from the index case was similar to viruses circulating in the local pigs. The case's grandfather was asymptomatic with sero-conversion. A total of 42.8% of swine sera were positive for European avian-like swine H1N1. This study highlighted the importance of performing surveillance on swine influenza to monitor new virus emergence in humans. © 2013 Elsevier Inc. All rights reserved.

  20. First Isolation of Hepatitis E Virus Genotype 4 in Europe through Swine Surveillance in the Netherlands and Belgium

    Science.gov (United States)

    Hakze-van der Honing, Renate W.; van Coillie, Els; Antonis, Adriaan F. G.; van der Poel, Wim H. M.

    2011-01-01

    Hepatitis E virus (HEV) genotypes 3 and 4 are a cause of human hepatitis and swine are considered the main reservoir. To study the HEV prevalence and characterize circulating HEV strains, fecal samples from swine in the Netherlands and Belgium were tested by RT-PCR. HEV prevalence in swine was 7–15%. The Dutch strains were characterized as genotype 3, subgroups 3a, 3c and 3f, closely related to sequences found in humans and swine earlier. The HEV strains found in Belgium belonged to genotypes 3f and 4b. The HEV genotype 4 strain was the first ever reported in swine in Europe and an experimental infection in pigs was performed to isolate the virus. The genotype 4 strain readily infected piglets and caused fever and virus shedding. Since HEV4 infections have been reported to run a more severe clinical course in humans this observation may have public health implications. PMID:21829641

  1. Clinical and laboratory features of dengue virus-infected travellers previously vaccinated against yellow fever

    NARCIS (Netherlands)

    Teichmann, Dieter; Göbels, Klaus; Niedrig, Matthias; Grobusch, Martin P.

    2003-01-01

    Dengue is a mosquito-borne viral infection endemic throughout the tropics and subtropics. The global prevalence of dengue has grown dramatically in recent years and it has become a major international public health concern. The close taxonomic relationships between yellow fever and dengue viruses

  2. Antibody responses of swine following infection with Mycoplasma hyopneumoniae, M. hyorhinis, M. hyosynoviae and M. flocculare.

    Science.gov (United States)

    Gomes Neto, João Carlos; Strait, Erin L; Raymond, Matthew; Ramirez, Alejandro; Minion, F Chris

    2014-11-07

    Several mycoplasma species possessing a range of virulence have been described in swine. The most commonly described are Mycoplasma hyopneumoniae, Mycoplasma hyorhinis, Mycoplasma hyosynoviae, and Mycoplasma flocculare. They are ubiquitious in many pig producing areas of the world, and except for M. hyopneumoniae, commercial antibody-based assays are lacking for most of these. Antibody cross-reactivity among these four mycoplasma species is not well characterized. Recently, the use of pen-based oral fluids for herd surveillance is of increasing interest. Thus, this study sought to measure pig antibody responses and the level of cross-reactivity in serum and pen-based oral fluids after challenge with four species of swine mycoplasmas. Four groups of four mycoplasma-free growing pigs were separately inoculated with the different mycoplasma species. Pen-based oral fluids and serum samples were collected weekly until necropsy. Species-specific Tween 20 ELISAs were used to measure antibody responses along with four other commercial M. hyopneumoniae ELISAs. Animals from all groups seroconverted to the challenge species of mycoplasma and no evidence of cross-contamination was observed. A delayed antibody response was seen with all but M. hyorhinis-infected pigs. Cross-reactive IgG responses were detected in M. hyopneumoniae- and M. flocculare-infected animals by the M. hyorhinis Tween 20 ELISA, while sera from M. hyosynoviae and M. flocculare-infected pigs were positive in one commercial assay. In pen-based oral fluids, specific anti-M. hyopneumoniae IgA responses were detected earlier after infection than serum IgG responses. In summary, while some antibody-based assays may have the potential for false positives, evidence of this was observed in the current study. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Rheumatic Fever

    Science.gov (United States)

    ... time, can lead to congestive heart failure. What causes rheumatic fever? Rheumatic fever is not an infection itself, but ... If the antibodies attack your heart, they can cause your heart valves to swell, which can ... is at risk for rheumatic fever? Fewer than 0.3% of people who have ...

  4. CDC Recommendations to Reduce the Risk of H3N2v Flu Virus Infection for Fairgoers and Swine Exhibitors

    Centers for Disease Control (CDC) Podcasts

    2012-09-10

    In this podcast, Dr. Lyn Finelli discusses CDC’s recommendations for reducing the risk of infection with H3N2v flu viruses for fairgoers and swine exhibitors.  Created: 9/10/2012 by National Center for Immunization and Respiratory Diseases (NCIRD).   Date Released: 9/10/2012.

  5. Two cases of Hantavirus infection in Crimean-Congo Haemorrhagic Fever endemic region

    Directory of Open Access Journals (Sweden)

    Mustafa Sünbül

    2012-09-01

    Full Text Available Crimean-Congo Hemorrhagic Fever (CCHF and Leptospirosis are endemic in our region. Hantavirus infections may beconfused with similar clinical picture zoonotic infections. Two patients with fever, malaise, cough, phlegm, nausea, vomiting,thrombocytopenia, renal failure, elevated transaminases, and a history of mouse contact were hospitalized in ourclinic with a presumptive diagnosis of leptospirosis, pneumonia, CCHF and Hantavirus infections. Empirical antibiotictreatment was initiated and CCHF and leptospirosis was ruled out with laboratory tests. Hantavirus immunoglobulin(Ig-G and Ig-M antibodies were detected positive by immunofluorescent antibody (IFA method in both cases but,Dobrova virus was detected in only one patient with immunoblotting methods. Both patients were discharged aftertreatment. Hantavirus infections may be misdiagnosed as zoonotic infections since they have similar clinical picture. Itshould be considered in the differential diagnosis of patients with a history of contact with mouse. J Microbiol Infect Dis2012; 2(3: 117-120Key words: Hantavirus, hemorrhagic fever, renal syndrome, pulmonary syndrome

  6. Proteome Profile of Swine Testicular Cells Infected with Porcine Transmissible Gastroenteritis Coronavirus

    Science.gov (United States)

    Ma, Ruili; Zhang, Yanming; Liu, Haiquan; Ning, Pengbo

    2014-01-01

    The interactions occurring between a virus and a host cell during a viral infection are complex. The purpose of this paper was to analyze altered cellular protein levels in porcine transmissible gastroenteritis coronavirus (TGEV)-infected swine testicular (ST) cells in order to determine potential virus-host interactions. A proteomic approach using isobaric tags for relative and absolute quantitation (iTRAQ)-coupled two-dimensional liquid chromatography-tandem mass spectrometry identification was conducted on the TGEV-infected ST cells. The results showed that the 4-plex iTRAQ-based quantitative approach identified 4,112 proteins, 146 of which showed significant changes in expression 48 h after infection. At 64 h post infection, 219 of these proteins showed significant change, further indicating that a larger number of proteomic changes appear to occur during the later stages of infection. Gene ontology analysis of the altered proteins showed enrichment in multiple biological processes, including cell adhesion, response to stress, generation of precursor metabolites and energy, cell motility, protein complex assembly, growth, developmental maturation, immune system process, extracellular matrix organization, locomotion, cell-cell signaling, neurological system process, and cell junction organization. Changes in the expression levels of transforming growth factor beta 1 (TGF-β1), caspase-8, and heat shock protein 90 alpha (HSP90α) were also verified by western blot analysis. To our knowledge, this study is the first time the response profile of ST host cells following TGEV infection has been analyzed using iTRAQ technology, and our description of the late proteomic changes that are occurring after the time of vigorous viral production are novel. Therefore, this study provides a solid foundation for further investigation, and will likely help us to better understand the mechanisms of TGEV infection and pathogenesis. PMID:25333634

  7. Proteome profile of swine testicular cells infected with porcine transmissible gastroenteritis coronavirus.

    Directory of Open Access Journals (Sweden)

    Ruili Ma

    Full Text Available The interactions occurring between a virus and a host cell during a viral infection are complex. The purpose of this paper was to analyze altered cellular protein levels in porcine transmissible gastroenteritis coronavirus (TGEV-infected swine testicular (ST cells in order to determine potential virus-host interactions. A proteomic approach using isobaric tags for relative and absolute quantitation (iTRAQ-coupled two-dimensional liquid chromatography-tandem mass spectrometry identification was conducted on the TGEV-infected ST cells. The results showed that the 4-plex iTRAQ-based quantitative approach identified 4,112 proteins, 146 of which showed significant changes in expression 48 h after infection. At 64 h post infection, 219 of these proteins showed significant change, further indicating that a larger number of proteomic changes appear to occur during the later stages of infection. Gene ontology analysis of the altered proteins showed enrichment in multiple biological processes, including cell adhesion, response to stress, generation of precursor metabolites and energy, cell motility, protein complex assembly, growth, developmental maturation, immune system process, extracellular matrix organization, locomotion, cell-cell signaling, neurological system process, and cell junction organization. Changes in the expression levels of transforming growth factor beta 1 (TGF-β1, caspase-8, and heat shock protein 90 alpha (HSP90α were also verified by western blot analysis. To our knowledge, this study is the first time the response profile of ST host cells following TGEV infection has been analyzed using iTRAQ technology, and our description of the late proteomic changes that are occurring after the time of vigorous viral production are novel. Therefore, this study provides a solid foundation for further investigation, and will likely help us to better understand the mechanisms of TGEV infection and pathogenesis.

  8. Experimental Infection of Swine by Isospora suis Biester 1934 for Species Confirmation

    Directory of Open Access Journals (Sweden)

    Silvia Maria Oliveira Sayd

    1998-11-01

    Full Text Available A survey of Isospora suis performed in 177 faecal samples from 30 swine farms detected thin wall type I. suis oocysts in seven samples. This type of oocyst measuring 23.9 by 20.7 mm had a retracted thin wall similar to that of the genus Sarcocystis. This type of oocysts, isolated from four different faecal samples, was inoculated in four-five-days-old piglets free of contamination in order to verify the life cycle and pathogenicity of the species. The pigs were kept in individual metal cages and fed with cow milk. Daily faecal collections and examinations were performed until the 21st day after infection. MacMaster and Sheather' s methods were used for oocyst counting and identification. Infected piglets produced yellowish-pasty diarrhoea with slight dehydration. The prepatent and patent periods were respectively from 6 to 9 and 3 to 10 days after infection. Oocyst elimination was interrupted on the 10th and 11th days after infection with biphasic cycles. Thin and thick wall oocysts were detected in the same faecal samples. Thin walls were not observed in unsporulated oocysts. The observations suggest that this type of oocysts could appear in specific strains which occur in the later stages of their development. These oocysts seem to be responsible for clinical and pathogenic signs of neonatal isosporosis in pigs.

  9. Immune evasion during foot-and-mouth disease virus infection of swine.

    Science.gov (United States)

    Golde, William T; Nfon, Charles K; Toka, Felix N

    2008-10-01

    The interface between successful pathogens and their hosts is often a tenuous balance. In acute viral infections, this balance involves induction and inhibition of innate responses. Foot-and-mouth disease virus (FMDV) is considered one of the most contagious viruses known and is characterized by rapid induction of clinical disease in cloven hoofed animals exposed to infection. Viral shedding is extensive before the equally rapid resolution of acute disease. This positive strand RNA virus is an extremely successful pathogen, due in part to the ability to interrupt the innate immune response. Previous reviews have described the inhibition of cellular innate responses in the infected cell both in vitro and in vivo. Here, we present a review of virus inhibition of cells that are a source of antiviral function in swine. Particularly in the case of dendritic cells and natural killer cells, the virus has evolved mechanisms to interrupt the normal function of these important mediators of innate function, even though these cells are not infected by the virus. Understanding how this virus subverts the innate response will provide valuable information for the development of rapidly acting biotherapeutics to use in response to an outbreak of FMDV.

  10. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-05-15

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

  12. 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.

  13. 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 pigs that had received IFN-γ. This study suggests involvement of Tcf-4 in IFN-γ-mediated immune regulation following CSFV vaccination. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

    International Nuclear Information System (INIS)

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

    2005-01-01

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

  15. Acute Q fever infection in Thuringia, Germany, after burial of roe deer fawn cadavers (Capreolus capreolus: a case report

    Directory of Open Access Journals (Sweden)

    B.T. Schleenvoigt

    2015-11-01

    Full Text Available We report on a case of a 48-year-old man who presented with acute Q fever infection after burying two fawn cadavers (Capreolus capreolus. Recent outbreaks of Q fever in Europe have been traced back to intensive goat breeding units, sheep flocks in the proximity of highly populated urban areas or to farmed deer. To our knowledge, this is the first case report describing Q fever infection in a human linked to roe deer as a source of infection.

  16. Detection of Genotype 4 Swine Hepatitis E Virus in Systemic Tissues in Cross-Species Infected Rabbits.

    Directory of Open Access Journals (Sweden)

    Qiaoxing Wu

    Full Text Available Increasing evidence demonstrates that hepatitis E virus (HEV can be transmitted across species. According to previous reports, swine HEV has two genotypes, genotype 3 and 4, and both can infect humans by the fecal-oral route. Thus, it is crucial for the control of HEV zoonotic transmission to evaluate the dynamics of viral shedding and distribution in different tissues during cross-species infection by HEV. In this study, rabbits were infected with genotype 4 swine HEV by the intraperitoneal route. The results showed that HEV RNA not only shed in the feces but also in the saliva of some rabbits during infection with swine HEV. Viremia appeared late after infection, and anti-HEV IgG was not obvious until the appearance of high viremia levels. After the rabbits were euthanized, a histopathological examination showed that the livers developed overt hepatitis accompanied by an elevation of alanine aminotransferase (ALT and aspartate transaminase (AST. Furthermore, HEV RNA was detected in various tissues, especially in the salivary glands and tonsils. Subsequently, negative-stranded HEV RNA was practiced in tissues with positive HEV RNA, which demonstrated that HEV replicated in the tissues. Next, we harvested additional tissues from the liver, salivary gland, tonsil, spleen, thymus gland, lymph node and intestine, which are known as replication sites of swine HEV. Additionally, we also observed the HEV antigen distributed in the organs above through immunohistochemical staining. These results demonstrate that rabbits could be used as an animal model for researching cross-species infection of genotype 4 HEV. It is also noteworthy that HEV can shed in the saliva and presents the risk of droplet transmission. These new data provide valuable information for understanding cross-species infection by HEV.

  17. Comparative Analysis of Avian and Swine Influenza Viruses Infections of Well Differentiated Lung Epithelial Cells of Turkey

    Directory of Open Access Journals (Sweden)

    Sahar Abd El Rahman

    2015-07-01

    Full Text Available Influenza viruses initiate infection by binding of the viral hemagglutinin to the cellular sialic acid residues. The precision-cut lung slice, as a valuable cultural tool of differentiated respiratory epithelial cells, is characterized by its ability to be viable for at least six days in-vitro, mimic in-vivo original cells and simply monitored by an inverted microscope. The aims of the study were to analyse the distribution of different sialic acid types in bronchus and parabronchial tissues of Turkey Precision Lung Slices (TPCLS, investigate the infection susceptibility of TPCLS by avian influenza (H9N2 and H7N7 and swine influenza (H3N2 viruses and evaluate the infection expression of TPCLS by different influenza viruses in correlation to the cellular sialic acids distribution after infection. The lectin stains and monoclonal antibodies prepared against nucleoprotein of influenza virus were used for analysing sialic acids distributions and viral antigen detection of TPCLS by immunoflourescent technique. The viral infective particles released from infected TPCLS by different avian and swine influenza viruses were titrated at different time intervals after infection. Both α2,3-linked and α2,6-linked sialic acids were expressed in the bronchus of TPCLS, while only α2,6-linked sialic acid was expressed in the parabronchial tissues. The indirect immunoflourescent technique showed variation of infection susceptibility of TPCLS parts by avian and swine influenza viruses. Infection was expressed in the bronchial epithelium by H9N2, H7N7 and H3N2, while in the parabronchial tissue by H9N2 and H3N2. Titration of the released infective viruses in the supernatant of infected TPCLS revealed that H9N2 could replicate faster than the other influenza viruses. TPCLS is a promising in-vitro model for viral infection study of turkey.

  18. A Novel Benzodiazepine Compound Inhibits Yellow Fever Virus Infection by Specifically Targeting NS4B Protein.

    Science.gov (United States)

    Guo, Fang; Wu, Shuo; Julander, Justin; Ma, Julia; Zhang, Xuexiang; Kulp, John; Cuconati, Andrea; Block, Timothy M; Du, Yanming; Guo, Ju-Tao; Chang, Jinhong

    2016-09-21

    Although a highly effective vaccine is available, the number of yellow fever cases has increased over the past two decades, which highlights the pressing need for antiviral therapeutics. In a high throughput screening campaign, we identified an acetic acid benzodiazepine (BDAA) compound, which potently inhibits yellow fever virus (YFV). Interestingly, while treatment of YFV infected cultures with 2 μM of BDAA reduced the virion production by greater than 2 logs, the compound is not active against 21 other viruses from 14 different viral families. Selection and genetic analysis of drug resistant viruses revealed that substitution of proline at amino acid 219 (P219) of the nonstructural protein 4B (NS4B) with serine, threonine or alanine confers YFV resistance to BDAA without apparent loss of replication fitness in cultured mammalian cells. However, substitution of P219 with glycine confers BDAA resistance with significant loss of replication ability. Bioinformatics analysis predicts that the P219 localizes at the endoplasmic reticulum lumen side of the fifth putative trans-membrane domain of NS4B and the mutation may render the viral protein incapable of interacting with BDAA. Our studies thus revealed important role and structural basis for NS4B protein in supporting YFV replication. Moreover, in YFV-infected hamsters, oral administration of BDAA protected 90% of the animals from death, significantly reduced viral load by greater than 2 logs and attenuated viral infection-induced liver injury and body weight loss. The encouraging preclinical results thus warrant further development of BDAA or its derivatives as antiviral agents to treat yellow fever. Yellow fever is an acute viral hemorrhagic disease which threatens approximately one billion people living in tropical areas of Africa and Latin America. Although a highly effective yellow fever vaccine has been available for more than seven decades, the low vaccination rate fails to prevent outbreaks in at

  19. Expression of myeloperoxidase in swine influenza virus (SIV)-infected neutrophils in lungs from pigs experimentally infected with SIV subtype H1N2.

    Science.gov (United States)

    Kim, Bongtae; Shin, Jeoung Hwa; Han, Kiwon; Seo, Hwi Won; Oh, Yeonsu; Kang, Ikjae; Park, Changhoon; Lee, Bog-Hieu; Jang, Jin Sil; Kim, Sung-Hoon; Chae, Chanhee

    2011-10-01

    The expression of myeloperoxidase (MPO) was examined in the swine influenza virus (SIV)-infected neutrophils in the lungs of pigs experimentally infected with swine influenza virus (SIV) subtype H1N2 by immunohistochemistry. Five pigs each from the infected and non-infected group were euthanized 1, 3, 5, 7, and 10 days post-inoculation (dpi). Immunohistochemical reactivity was mainly seen in neutrophils. The score for pulmonary histopathological lesions correlated with the score for MPO immunohistochemical reactivity (r ( s ) = 0.962, P < 0.01). In addition, the score for in situ hybridization of SIV nucleic acid correlated with the score for MPO immunohistochemical reactivity (r ( s ) = 0.976, P < 0.01). These results suggest neutrophils are one of the primary effector cells in the early phase of SIV infection in pigs.

  20. Distribution of sialic acid receptors and influenza A viruses of avian and swine origin and in experimentally infected pigs

    DEFF Research Database (Denmark)

    Trebbien, Ramona; Larsen, Lars Erik; Viuff, Birgitte M.

    2011-01-01

    Background: Pigs are considered susceptible to influenza A virus infections from different host origins because earlier studies have shown that they have receptors for both avian (sialic acid-alpha-2,3-terminal saccharides (SAalpha- 2,3)) and swine/human (SA-alpha-2,6) influenza viruses in the up......Background: Pigs are considered susceptible to influenza A virus infections from different host origins because earlier studies have shown that they have receptors for both avian (sialic acid-alpha-2,3-terminal saccharides (SAalpha- 2,3)) and swine/human (SA-alpha-2,6) influenza viruses...... acts as a mixing vessel between human and avian influenza viruses. Furthermore, it was shown that AIV prefers to infect alveolar type II epithelial cells in pigs. This corresponds with findings in humans emphasising the resemblance between the two species....

  1. Fever after a stay in the tropics: clinical spectrum and outcome in HIV-infected travelers and migrants.

    Science.gov (United States)

    Bottieau, Emmanuel; Florence, Eric; Clerinx, Jan; Vlieghe, Erika; Vekemans, Marc; Moerman, Filip; Lynen, Lut; Colebunders, Robert; Van Gompel, Alfons; Van den Ende, Jef

    2008-08-15

    To investigate the epidemiology and clinical spectrum of fever in HIV-infected returning travelers and migrants. From April 2000 to December 2006, we explored prospectively, at our referral travel/HIV clinics, the etiology and outcome of febrile illnesses developing within 3 months after a stay in the tropics. For this study, we compared the morbidity profile between HIV-infected individuals and all other cases tested HIV negative. Of the 1850 adults (15 years and older) evaluated for 1921 fever episodes, 93 (5%) had HIV infection, including 5 presenting with primary infection. HIV prevalence was 2% in western travelers or expatriates, 11% in travelers "visiting friends and relatives," and 24% in foreign visitors/migrants. Fever episodes (n = 104) occurring in the HIV-infected individuals were mainly due to opportunistic infections (23%, including tuberculosis), respiratory tract infections (20%), sexually transmitted infections (9%), and noninfectious diseases (7%). All these conditions were more frequently diagnosed than in HIV-negative travelers (1035 fever episodes), although tropical infections (mostly malaria) were proportionally less prevalent. Morbidity (rate and duration of hospitalization) was more considerable in HIV-infected patients than in HIV-negative individuals. HIV infection was frequent in returning travelers and migrants presenting with fever at our setting and affected strongly the diagnostic spectrum and overall morbidity.

  2. Treatment model of dengue hemorrhagic fever infection in human body

    Science.gov (United States)

    Handayani, D.; Nuraini, N.; Primasari, N.; Wijaya, K. P.

    2014-03-01

    The treatment model of DHF presented in this paper involves the dynamic of five time-dependent compartments, i.e. susceptible, infected, free virus particle, immune cell, and haematocrit level. The treatment model is investigated based on normalization of haematocrit level, which is expressed as intravenous fluid infusion control. We analyze the stability of the disease free equilibrium and the endemic equilibrium. The numerical simulations will explain the dynamic of each compartment in human body. These results show particularly that infected compartment and free virus particle compartment are tend to be vanished in two weeks after the onset of dengue virus. However, these simulation results also show that without the treatment, the haematocrit level will decrease even though not up to the normal level. Therefore the effective haematocrit normalization should be done with the treatment control.

  3. Multiple Infections of Malaria and Typhoid Fever Among People ...

    African Journals Online (AJOL)

    Average counts of other hematologic parameters were: 514+21 for CD4 cell count; 15.01 ± 4.1 for WBC; 84.56 ± 81 for lymphocyte count, and 69.18± 3.0 for red blood cell (PCV). On the gender level, out of the 546 triply infected persons observed, 232 were males, and 314, females, with preponderance of female to male ...

  4. [Human parechovirus-3 infection in a neonate with fever and suspected sepsis].

    Science.gov (United States)

    Calvo, C; García-García, M L; Arroyas, M; Trallero, G; Cabrerizo, M

    2014-07-01

    The human parechovirus (HPeV) are viruses of the recently described Picornaviridae family and are causing several infections in young children. The pathology associated with these viruses is beginning to emerge. The HPeV type 3, has been described particularly in association with sepsis-like febrile syndromes, meningitis and encephalitis in very young infants and neonates. We report the case of a 14-day-old girl with a fever and clinical sepsis that required hospitalization and in which HPeV-3 was identified in the cerebrospinal fluid. The blood, urine and cerebrospinal fluid bacterial cultures were negative, and the patient improved. This case illustrates the usefulness of investigating parechovirus infection in neonates with fever or suspected sepsis. Copyright © 2013 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

  5. Neutropenic Fever.

    Science.gov (United States)

    White, Lindsey; Ybarra, Michael

    2017-12-01

    Fever is a common presenting complaint among adult or pediatric patients in the emergency department setting. Although fever in healthy individuals does not necessarily indicate severe illness, fever in patients with neutropenia may herald a life-threatening infection. Therefore, prompt recognition of patients with neutropenic fever is imperative. Serious bacterial illness is a significant cause of morbidity and mortality for neutropenic patients. Neutropenic fever should trigger the initiation of a rapid work-up and the administration of empiric systemic antibiotic therapy to attenuate or avoid the progression along the spectrum of sepsis, severe sepsis, septic shock syndrome, and death. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. 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.

    . Blood samples were collected from all pigs at predetermined days for immunological and virological evaluation. The duration of the experiments was 4 weeks. At PID 28/29, all pigs were euthanized and subjected to post mortem examination. Table 1 Experiment control pigs virus-inoculated pigs age...... 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...

  7. 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...

  8. Prevention of Infection in Patients With Hematologic Cancer and Persistent Fever Caused by a Low White Blood Cell Count

    Science.gov (United States)

    2012-09-20

    Bone Marrow Suppression; Fever, Sweats, and Hot Flashes; Infection; Leukemia; Lymphoma; Multiple Myeloma and Plasma Cell Neoplasm; Myelodysplastic Syndromes; Unspecified Adult Solid Tumor, Protocol Specific; Unspecified Childhood Solid Tumor, Protocol Specific

  9. A Haploid Genetic Screen Identifies Heparan Sulfate Proteoglycans Supporting Rift Valley Fever Virus Infection.

    Science.gov (United States)

    Riblett, Amber M; Blomen, Vincent A; Jae, Lucas T; Altamura, Louis A; Doms, Robert W; Brummelkamp, Thijn R; Wojcechowskyj, Jason A

    2015-11-18

    Rift Valley fever virus (RVFV) causes recurrent insect-borne epizootics throughout the African continent, and infection of humans can lead to a lethal hemorrhagic fever syndrome. Deep mutagenesis of haploid human cells was used to identify host factors required for RVFV infection. This screen identified a suite of enzymes involved in glycosaminoglycan (GAG) biogenesis and transport, including several components of the cis-oligomeric Golgi (COG) complex, one of the central components of Golgi complex trafficking. In addition, disruption of PTAR1 led to RVFV resistance as well as reduced heparan sulfate surface levels, consistent with recent observations that PTAR1-deficient cells exhibit altered Golgi complex morphology and glycosylation defects. A variety of biochemical and genetic approaches were utilized to show that both pathogenic and attenuated RVFV strains require GAGs for efficient infection on some, but not all, cell types, with the block to infection being at the level of virion attachment. Examination of other members of the Bunyaviridae family for GAG-dependent infection suggested that the interaction with GAGs is not universal among bunyaviruses, indicating that these viruses, as well as RVFV on certain cell types, employ additional unidentified virion attachment factors and/or receptors. Rift Valley fever virus (RVFV) is an emerging pathogen that can cause severe disease in humans and animals. Epizootics among livestock populations lead to high mortality rates and can be economically devastating. Human epidemics of Rift Valley fever, often initiated by contact with infected animals, are characterized by a febrile disease that sometimes leads to encephalitis or hemorrhagic fever. The global burden of the pathogen is increasing because it has recently disseminated beyond Africa, which is of particular concern because the virus can be transmitted by widely distributed mosquito species. There are no FDA-licensed vaccines or antiviral agents with activity

  10. Existing and potential infection risk zones of yellow fever worldwide: a modelling analysis

    Directory of Open Access Journals (Sweden)

    Freya M Shearer, BSc

    2018-03-01

    Full Text Available Summary: Background: Yellow fever cases are under-reported and the exact distribution of the disease is unknown. An effective vaccine is available but more information is needed about which populations within risk zones should be targeted to implement interventions. Substantial outbreaks of yellow fever in Angola, Democratic Republic of the Congo, and Brazil, coupled with the global expansion of the range of its main urban vector, Aedes aegypti, suggest that yellow fever has the propensity to spread further internationally. The aim of this study was to estimate the disease's contemporary distribution and potential for spread into new areas to help inform optimal control and prevention strategies. Methods: We assembled 1155 geographical records of yellow fever virus infection in people from 1970 to 2016. We used a Poisson point process boosted regression tree model that explicitly incorporated environmental and biological explanatory covariates, vaccination coverage, and spatial variability in disease reporting rates to predict the relative risk of apparent yellow fever virus infection at a 5 × 5 km resolution across all risk zones (47 countries across the Americas and Africa. We also used the fitted model to predict the receptivity of areas outside at-risk zones to the introduction or reintroduction of yellow fever transmission. By use of previously published estimates of annual national case numbers, we used the model to map subnational variation in incidence of yellow fever across at-risk countries and to estimate the number of cases averted by vaccination worldwide. Findings: Substantial international and subnational spatial variation exists in relative risk and incidence of yellow fever as well as varied success of vaccination in reducing incidence in several high-risk regions, including Brazil, Cameroon, and Togo. Areas with the highest predicted average annual case numbers include large parts of Nigeria, the Democratic Republic of the

  11. Existing and potential infection risk zones of yellow fever worldwide: a modelling analysis.

    Science.gov (United States)

    Shearer, Freya M; Longbottom, Joshua; Browne, Annie J; Pigott, David M; Brady, Oliver J; Kraemer, Moritz U G; Marinho, Fatima; Yactayo, Sergio; de Araújo, Valdelaine E M; da Nóbrega, Aglaêr A; Fullman, Nancy; Ray, Sarah E; Mosser, Jonathan F; Stanaway, Jeffrey D; Lim, Stephen S; Reiner, Robert C; Moyes, Catherine L; Hay, Simon I; Golding, Nick

    2018-03-01

    Yellow fever cases are under-reported and the exact distribution of the disease is unknown. An effective vaccine is available but more information is needed about which populations within risk zones should be targeted to implement interventions. Substantial outbreaks of yellow fever in Angola, Democratic Republic of the Congo, and Brazil, coupled with the global expansion of the range of its main urban vector, Aedes aegypti, suggest that yellow fever has the propensity to spread further internationally. The aim of this study was to estimate the disease's contemporary distribution and potential for spread into new areas to help inform optimal control and prevention strategies. We assembled 1155 geographical records of yellow fever virus infection in people from 1970 to 2016. We used a Poisson point process boosted regression tree model that explicitly incorporated environmental and biological explanatory covariates, vaccination coverage, and spatial variability in disease reporting rates to predict the relative risk of apparent yellow fever virus infection at a 5 × 5 km resolution across all risk zones (47 countries across the Americas and Africa). We also used the fitted model to predict the receptivity of areas outside at-risk zones to the introduction or reintroduction of yellow fever transmission. By use of previously published estimates of annual national case numbers, we used the model to map subnational variation in incidence of yellow fever across at-risk countries and to estimate the number of cases averted by vaccination worldwide. Substantial international and subnational spatial variation exists in relative risk and incidence of yellow fever as well as varied success of vaccination in reducing incidence in several high-risk regions, including Brazil, Cameroon, and Togo. Areas with the highest predicted average annual case numbers include large parts of Nigeria, the Democratic Republic of the Congo, and South Sudan, where vaccination coverage in 2016

  12. C-reactive protein, haptoglobin, serum amyloid A and pig major acute phase protein response in pigs simultaneously infected with H1N1 swine influenza virus and Pasteurella multocida.

    Science.gov (United States)

    Pomorska-Mól, Małgorzata; Markowska-Daniel, Iwona; Kwit, Krzysztof; Stępniewska, Katarzyna; Pejsak, Zygmunt

    2013-01-18

    Swine influenza (SI) is an acute respiratory disease caused by swine influenza virus (SIV). Swine influenza is generally characterized by acute onset of fever and respiratory symptoms. The most frequent complications of influenza are secondary bacterial pneumonia. The objective of this work was to study the acute phase proteins (APP) responses after coinfection of piglets with H1N1 swine influenza virus (SwH1N1) and Pasteurella multocida (Pm) in order to identify whether the individual APP response correlate with disease severity and whether APP could be used as markers of the health status of coinfected pigs. In all coinfected pigs clinical sings, including fever, coughing and dyspnea, were seen. Viral shedding was observed from 2 to 7 dpi. The mean level of antibodies against Pm dermonecrotoxin in infected piglets increase significantly from 7 dpi. Anti-SwH1N1 antibodies in the serum were detected from 7 dpi. The concentration of C-reactive protein (CRP) increased significantly at 1 dpi as compared to control pigs, and remained significantly higher to 3 dpi. Level of serum amyloid A (SAA) was significantly higher from 2 to 3 dpi. Haptoglobin (Hp) was significantly elevated from 3 dpi to the end of study, while pig major acute phase protein (Pig-MAP) from 3 to 7 dpi. The concentrations of CRP, Hp and SAA significantly increased before specific antibodies were detected. Positive correlations were found between serum concentration of Hp and SAA and lung scores, and between clinical score and concentrations of Pig-MAP and SAA. The results of current study confirmed that monitoring of APP may revealed ongoing infection, and in this way may be useful in selecting clinically healthy pigs (i.e. before integration into an uninfected herd). Present results corroborated our previous findings that SAA could be a potentially useful indicator in experimental infection studies (e.g. vaccine efficiency investigations) or as a marker for disease severity, because of correlation

  13. Kinetic Study of Yellow Fever 17DD Viral Infection in Gallus gallus domesticus Embryos

    Science.gov (United States)

    Manso, Pedro Paulo de Abreu; E. P. Dias de Oliveira, Bárbara Cristina; Carvalho de Sequeira, Patrícia; Rodrigues Maia de Souza, Yuli; dos Santos Ferro, Jessica Maria; da Silva, Igor José; Gonçalves Caputo, Luzia Fátima; Tavares Guedes, Priscila; Araujo Cunha dos Santos, Alexandre; da Silva Freire, Marcos; Bonaldo, Myrna Cristina; Pelajo Machado, Marcelo

    2016-01-01

    Yellow fever continues to be an important epidemiological problem in Africa and South America even though the disease can be controlled by vaccination. The vaccine has been produced since 1937 and is based on YFV 17DD chicken embryo infection. However, little is known about the histopathological background of virus infection and replication in this model. Here we show by morphological and molecular methods (brightfield and confocal microscopies, immunofluorescence, nested-PCR and sequencing) the kinetics of YFV 17DD infection in chicken embryos with 9 days of development, encompassing 24 to 96 hours post infection. Our principal findings indicate that the main cells involved in virus production are myoblasts with a mesenchymal shape, which also are the first cells to express virus proteins in Gallus gallus embryos at 48 hours after infection. At 72 hours post infection, we observed an increase of infected cells in embryos. Many sites are thus affected in the infection sequence, especially the skeletal muscle. We were also able to confirm an increase of nervous system infection at 96 hours post infection. Our data contribute to the comprehension of the pathogenesis of YF 17DD virus infection in Gallus gallus embryos. PMID:27158977

  14. 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

  15. Hospitalized acute patients with fever and severe infection have lower mortality than patients with hypo- or normothermia

    DEFF Research Database (Denmark)

    Henriksen, Daniel Pilsgaard; Havshøj, Ulrik; Pedersen, Peter Bank

    2016-01-01

    OBJECTIVES: Severe infection is a frequent cause of admission to an acute medical unit (AMU). However, not all infected patients present with fever. The aim was to assess differences in 30-day mortality among patients hospitalized with community-acquired severe infection presenting with hypo......-, normo- or fever. METHODS: A retrospective single-center follow-up at an AMU from August 1 2009 to August 31 2011. Patients were included the first time they presented with severe infection within the study period. Temperature was categorized into hypothermia (...), and fever (>38.0C). Severe infection was defined as a discharge diagnosis indicating infection combined with organ failure within the first 24 hours after arrival. Multivariable Cox regression analysis was computed to assess the association between temperature and 30-day mortality. RESULTS: A total of 2...

  16. 9 CFR 93.505 - Certificate for swine.

    Science.gov (United States)

    2010-01-01

    ... certificate shall show that the entire region of origin is free of classical swine fever. (b) Swine from.... (Approved by the Office of Management and Budget under control number 0579-0165) [55 FR 31495, Aug. 2, 1990...

  17. Two years of surveillance of influenza a virus infection in a swine herd. Results of virological, serological and pathological studies.

    Science.gov (United States)

    Cappuccio, Javier; Dibarbora, Marina; Lozada, Inés; Quiroga, Alejandra; Olivera, Valeria; Dángelo, Marta; Pérez, Estefanía; Barrales, Hernán; Perfumo, Carlos; Pereda, Ariel; Pérez, Daniel R

    2017-02-01

    Swine farms provide a dynamic environment for the evolution of influenza A viruses (IAVs). The present report shows the results of a surveillance effort of IAV infection in one commercial swine farm in Argentina. Two cross-sectional serological and virological studies (n=480) were carried out in 2011 and 2012. Virus shedding was detected in nasal samples from pigs from ages 7, 21 and 42-days old. More than 90% of sows and gilts but less than 40% of 21-days old piglets had antibodies against IAV. In addition, IAV was detected in 8/17 nasal swabs and 10/15 lung samples taken from necropsied pigs. A subset of these samples was further processed for virus isolation resulting in 6 viruses of the H1N2 subtype (δ2 cluster). Pathological studies revealed an association between suppurative bronchopneumonia and necrotizing bronchiolitis with IAV positive samples. Statistical analyses showed that the degree of lesions in bronchi, bronchiole, and alveoli was higher in lungs positive to IAV. The results of this study depict the relevance of continuing long-term active surveillance of IAV in swine populations to establish IAV evolution relevant to swine and humans. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Role of neutrophil to lymphocyte and monocyte to lymphocyte ratios in the diagnosis of bacterial infection in patients with fever.

    Science.gov (United States)

    Naess, Are; Nilssen, Siri Saervold; Mo, Reidun; Eide, Geir Egil; Sjursen, Haakon

    2017-06-01

    To study the role of the neutrophil:lymphocyte ratio (NLR) and monocyte:lymphocyte ratio (MLR) in discriminating between different patient groups hospitalized for fever due to infection and those without infection. For 299 patients admitted to hospital for fever with unknown cause, a number of characteristics including NLR and MLR were recorded. These characteristics were used in a multiple multinomial regression analysis to estimate the probability of a final diagnostic group of bacterial, viral, clinically confirmed, or no infection. Both NLR and MLR significantly predicted final diagnostic group. Being highly correlated, however, both variables could not be retained in the same model. Both variables also interacted significantly with duration of fever. Generally, higher values of NLR and MLR indicated larger probabilities for bacterial infection and low probabilities for viral infection. Patients with septicemia had significantly higher NLR compared to patients with other bacterial infections with fever for less than one week. White blood cell counts, neutrophil counts, and C-reactive proteins did not differ significantly between septicemia and the other bacterial infection groups. NLR is a more useful diagnostic tool to identify patients with septicemia than other more commonly used diagnostic blood tests. NLR and MLR may be useful in the diagnosis of bacterial infection among patients hospitalized for fever.

  19. African swine fever control and market integration in Ugandan peri-urban smallholder pig value chains: An ex-ante impact assessment of interventions and their interaction.

    Science.gov (United States)

    Ouma, Emily; Dione, Michel; Birungi, Rosemirta; Lule, Peter; Mayega, Lawrence; Dizyee, Kanar

    2018-03-01

    Pig production in peri-urban smallholder value chains in Uganda is severely constrained by impact of disease, particularly African swine fever (ASF), and the economic consequences of an inefficient pig value chain. Interventions in the form of biosecurity to control ASF disease outbreaks and pig business hub models to better link smallholder farmers to pig markets have the potential to address the constraints. However, there is a dearth of evidence of the effects of the interventions on performance and distribution of outcomes along the pig value chain. An ex-ante impact assessment utilising System Dynamics model was used to assess the impact of the interventions in peri-urban pig value chains in Masaka district. The results showed that although implementation of biosecurity interventions results in reduction of ASF outbreaks, it also leads to a 6.3% reduction in farmer profit margins per year but more than 7% increase in other value chain actors' margins. The pig business hub intervention alone results in positive margins for all value chain actors but minimal reduction in ASF outbreaks. When biosecurity and the pig business hub interventions are implemented together, the interaction effects of the interventions result in positive outcomes for both the control of ASF and improvement in farmers' margins. Farmers may therefore be unwilling to adopt biosecurity practices if implemented alone to control ASF outbreaks unless there is a corresponding financial incentive to compensate for the high costs. This has implications for policy or developing institutions to facilitate cost sharing arrangement among chain actors and/or third party subsidy to provide incentives for producers to adopt biosecurity measures. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

    Halasa, Tariq; Bøtner, Anette; Mortensen, Sten; Christensen, Hanne; Wulff, Sisse Birk; Boklund, Anette

    2018-01-01

    African swine fever (ASF) is a notifiable infectious disease. The disease is endemic in certain regions in Eastern Europe constituting a risk of ASF spread toward Western Europe. Therefore, as part of contingency planning, it is important to continuously explore strategies that can effectively control an epidemic of ASF. A previously published and well documented simulation model for ASF virus spread between herds was used to examine the epidemiologic and economic impacts of the duration and size of the control zones around affected herds. In the current study, scenarios were run, where the duration of the protection and surveillance zones were reduced from 50 and 45 days to 35 and 25 days or to 35 and 25 days, respectively. These scenarios were run with or without enlargement of the surveillance zone around detected herds from 10 to 15 km. The scenarios were also run with only clinical or clinical and serological surveillance of herds within the zones. Sensitivity analysis was conducted on influential input parameters in the model. The model predicts that reducing the duration of the protection and surveillance zones has no impact on the epidemiological consequences of the epidemics, while it may result in a substantial reduction in the total economic losses. In addition, the model predicts that increasing the size of the surveillance zone from 10 to 15 km may reduce both the epidemic duration and the total economic losses, in case of large epidemics. The ranking of the control strategies by the total costs of the epidemics was not influenced by changes of input parameters in the sensitivity analyses.

  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.

    Science.gov (United States)

    Elbers, A R W; Gorgievski-Duijvesteijn, M J; van der Velden, P G; Loeffen, W L A; Zarafshani, K

    2010-04-21

    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 makers from the veterinary authorities, and representatives of veterinary practitioners and pig farmer unions. Personal interviews with a small group of pig farmers and practitioners were held to check limitations raised and solutions proposed during the focus group sessions. An electronic questionnaire was mailed to pig farmers and practitioners to investigate perceptions and attitudes with respect to clinically suspect situations possibly caused by CSF. After triangulating the responses of veterinary authorities, veterinary practitioners and farmers, six themes emerged across all groups: (1) lack of knowledge on the early signs of CSF; (2) guilt, shame and prejudice; (3) negative opinion on control measures; (4) dissatisfaction with post-reporting procedures; (5) lack of trust in government bodies; (6) uncertainty and lack of transparency of reporting procedures. The following solutions to facilitate early detection of CSF were put forward: (a) development of a clinical decision-support system for vets and farmers, in order to get faster diagnosis and detection of CSF; (b) possibility to submit blood samples directly to the reference laboratory to exclude CSF in a clinical situation with non-specific clinical signs, without isolation of the farm and free of charge for the individual farmer; (c) decrease social and economic consequences of reporting CSF, for example by improving the public opinion on first reports; (d) better schooling of veterinary officers to deal with emotions and insecurity of farmers in the process after reporting; (e) better communication of rules and regulations, where to report, what will happen next; (f) up-to-date website with information and

  2. Implementation of a Regional Training Program on African Swine Fever As Part of the Cooperative Biological Engagement Program across the Caucasus Region

    Directory of Open Access Journals (Sweden)

    Marco De Nardi

    2017-10-01

    Full Text Available A training and outreach program to increase public awareness of African swine fever (ASF was implemented by Defense Threat Reduction Agency and the Ministries of Agriculture in Armenia, Georgia, Kazakhstan, and Ukraine. The implementing agency was the company SAFOSO (Switzerland. Integration of this regional effort was administered by subject matter experts for each country. The main teaching effort of this project was to develop a comprehensive regional public outreach campaign through a network of expertise and knowledge for the control and prevention of ASF in four neighboring countries that experience similar issues with this disease. Gaps in disease knowledge, legislation, and outbreak preparedness in each country were all addressed. Because ASF is a pathogen with bioterrorism potential and of great veterinary health importance that is responsible for major economic instability, the project team developed public outreach programs to train veterinarians in the partner countries to accurately and rapidly identify ASF activity and report it to international veterinary health agencies. The project implementers facilitated four regional meetings to develop this outreach program, which was later disseminated in each partner country. Partner country participants were trained as trainers to implement the outreach program in their respective countries. In this paper, we describe the development, execution, and evaluation of the ASF training and outreach program that reached more than 13,000 veterinarians, farmers, and hunters in the partner countries. Additionally, more than 120,000 booklets, flyers, leaflets, guidelines, and posters were distributed during the outreach campaign. Pre- and post-ASF knowledge exams were developed. The overall success of the project was demonstrated in that the principles of developing and conducting a public outreach program were established, and these foundational teachings can be applied within a single country or

  3. African swine fever virus transmission cycles in Central Europe: Evaluation of wild boar-soft tick contacts through detection of antibodies against Ornithodoros erraticus saliva antigen.

    Science.gov (United States)

    Pietschmann, Jana; Mur, Lina; Blome, Sandra; Beer, Martin; Pérez-Sánchez, Ricardo; Oleaga, Ana; Sánchez-Vizcaíno, José Manuel

    2016-01-04

    African swine fever (ASF) is one of the most complex viral diseases affecting both domestic and wild pigs. It is caused by ASF virus (ASFV), the only DNA virus which can be efficiently transmitted by an arthropod vector, soft ticks of the genus Ornithodoros. These ticks can be part of ASFV-transmission cycles, and in Europe, O. erraticus was shown to be responsible for long-term maintenance of ASFV in Spain and Portugal. In 2014, the disease has been reintroduced into the European Union, affecting domestic pigs and, importantly, also the Eurasian wild boar population. In a first attempt to assess the risk of a tick-wild boar transmission cycle in Central Europe that would further complicate eradication of the disease, over 700 pre-existing serum samples from wild boar hunted in four representative German Federal States were investigated for the presence of antibodies directed against salivary antigen of Ornithodoros erraticus ticks using an indirect ELISA format. Out of these samples, 16 reacted with moderate to high optical densities that could be indicative of tick bites in sampled wild boar. However, these samples did not show a spatial clustering (they were collected from distant geographical regions) and were of bad quality (hemolysis/impurities). Furthermore, all positive samples came from areas with suboptimal climate for soft ticks. For this reason, false positive reactions are likely. In conclusion, the study did not provide stringent evidence for soft tick-wild boar contact in the investigated German Federal States and thus, a relevant involvement in the epidemiology of ASF in German wild boar is unlikely. This fact would facilitate the eradication of ASF in the area, although other complex relations (wild boar biology and interactions with domestic pigs) need to be considered.

  4. 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.

  5. 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.

  6. 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.

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

    Science.gov (United States)

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

    2014-08-01

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

  8. 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

    Directory of Open Access Journals (Sweden)

    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

  9. Monitoring procalcitonin in febrile neutropenia: what is its utility for initial diagnosis of infection and reassessment in persistent fever?

    Directory of Open Access Journals (Sweden)

    James Owen Robinson

    Full Text Available BACKGROUND: Management of febrile neutropenic episodes (FE is challenged by lacking microbiological and clinical documentation of infection. We aimed at evaluating the utility of monitoring blood procalcitonin (PCT in FE for initial diagnosis of infection and reassessment in persistent fever. METHODS: PCT kinetics was prospectively monitored in 194 consecutive FE (1771 blood samples: 65 microbiologically documented infections (MDI, 33.5%; 49 due to non-coagulase-negative staphylococci, non-CNS, 68 clinically documented infections (CDI, 35%; 39 deep-seated, and 61 fever of unexplained origin (FUO, 31.5%. RESULTS: At fever onset median PCT was 190 pg/mL (range 30-26'800, without significant difference among MDI, CDI and FUO. PCT peak occurred on day 2 after onset of fever: non-CNS-MDI/deep-seated-CDI (656, 80-86350 vs. FUO (205, 33-771; p500 pg/mL distinguished non-CNS-MDI/deep-seated-CDI from FUO with 56% sensitivity and 90% specificity. PCT was >500 pg/ml in only 10% of FUO (688, 570-771. A PCT peak >500 pg/mL (1196, 524-11950 occurred beyond 3 days of persistent fever in 17/21 (81% invasive fungal diseases (IFD. This late PCT peak identified IFD with 81% sensitivity and 57% specificity and preceded diagnosis according to EORTC-MSG criteria in 41% of cases. In IFD responding to therapy, median days to PCT <500 pg/mL and defervescence were 5 (1-23 vs. 10 (3-22; p = 0.026, respectively. CONCLUSION: While procalcitonin is not useful for diagnosis of infection at onset of neutropenic fever, it may help to distinguish a minority of potentially severe infections among FUOs on day 2 after onset of fever. In persistent fever monitoring procalcitonin contributes to early diagnosis and follow-up of invasive mycoses.

  10. Enzyme-Linked Immunosorbent Assay Using a Virus Type-Specific Peptide Based on a Subdomain of Envelope Protein Erns for Serologic Diagnosis of Pestivirus Infections in Swine

    Science.gov (United States)

    Langedijk, J. P. M.; Middel, W. G. J.; Meloen, R. H.; Kramps, J. A.; de Smit, J. A.

    2001-01-01

    Peptides deduced from the C-terminal end (residues 191 to 227) of pestivirus envelope protein Erns were used to develop enzyme-linked immunosorbent assays (ELISAs) to measure specifically antibodies against different types of pestiviruses. The choice of the peptide was based on the modular structure of the Erns protein, and the peptide was selected for its probable independent folding and good exposure, which would make it a good candidate for an antigenic peptide to be used in a diagnostic test. A solid-phase peptide ELISA which was cross-reactive for several types of pestivirus antibodies and which can be used for the general detection of pestivirus antibodies was developed. To identify type-specific pestivirus antibodies, a liquid-phase peptide ELISA, with a labeled, specific classical swine fever virus (CSFV) peptide and an unlabeled bovine viral diarrhea virus peptide to block cross-reactivity, was developed. Specificity and sensitivity of the liquid-phase peptide ELISA for CSFV were 98 and 100%, respectively. Because the peptide is a fragment of the Erns protein, it can be used to differentiate between infected and vaccinated animals when a vaccine based on the E2 protein, which is another pestivirus envelope protein, is used. PMID:11230402

  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...... 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...

  12. A novel relapsing fever Borrelia sp. infects the salivary glands of the molted hard tick, Amblyomma geoemydae.

    Science.gov (United States)

    Takano, Ai; Sugimori, Chieko; Fujita, Hiromi; Kadosaka, Teruki; Taylor, Kyle R; Tsubota, Toshio; Konnai, Satoru; Tajima, Tomoko; Sato, Kozue; Watanabe, Haruo; Ohnishi, Makoto; Kawabata, Hiroki

    2012-09-01

    A novel relapsing fever Borrelia sp. was found in Amblyomma geoemydae in Japan. The novel Borrelia sp. was phylogenetically related to the hard (ixodid) tick-borne relapsing fever Borrelia spp. Borrelia miyamotoi and B. lonestari. The novel relapsing fever Borrelia sp. was detected in 39 A. geoemydae (39/274: 14.2%), of which 14 (14/274: 5.1%) were co-infected with the novel relapsing fever Borrelia sp. and Borrelia sp. tAG, one of the reptile-associated borreliae. Transstadial transmission of the novel relapsing fever Borrelia sp. occurred in the tick midgut and the salivary glands, although Borrelia sp. tAG was only detected in the tick midgut. The difference of the borrelial niche in molted ticks might be associated with borrelial characterization. Copyright © 2012. Published by Elsevier GmbH.

  13. Alterations in the Aedes aegypti transcriptome during infection with West Nile, dengue and yellow fever viruses.

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    Tonya M Colpitts

    2011-09-01

    Full Text Available West Nile (WNV, dengue (DENV and yellow fever (YFV viruses are (reemerging, mosquito-borne flaviviruses that cause human disease and mortality worldwide. Alterations in mosquito gene expression common and unique to individual flaviviral infections are poorly understood. Here, we present a microarray analysis of the Aedes aegypti transcriptome over time during infection with DENV, WNV or YFV. We identified 203 mosquito genes that were ≥ 5-fold differentially up-regulated (DUR and 202 genes that were ≥ 10-fold differentially down-regulated (DDR during infection with one of the three flaviviruses. Comparative analysis revealed that the expression profile of 20 DUR genes and 15 DDR genes was quite similar between the three flaviviruses on D1 of infection, indicating a potentially conserved transcriptomic signature of flaviviral infection. Bioinformatics analysis revealed changes in expression of genes from diverse cellular processes, including ion binding, transport, metabolic processes and peptidase activity. We also demonstrate that virally-regulated gene expression is tissue-specific. The overexpression of several virally down-regulated genes decreased WNV infection in mosquito cells and Aedes aegypti mosquitoes. Among these, a pupal cuticle protein was shown to bind WNV envelope protein, leading to inhibition of infection in vitro and the prevention of lethal WNV encephalitis in mice. This work provides an extensive list of targets for controlling flaviviral infection in mosquitoes that may also be used to develop broad preventative and therapeutic measures for multiple flaviviruses.

  14. Dengue fever

    African Journals Online (AJOL)

    Introduction. Dengue fever is caused by dengue viruses. (DENV). Transmission of DENV has increased dramatically in the past two decades making DENV the most important human pathogens among arthropod-borne viruses (1). About 50-. 100 million dengue fever infections occur every year in tropical and subtropical.

  15. Prior infection of pigs with a genotype 3 swine hepatitis E virus (HEV) protects against subsequent challenges with homologous and heterologous genotypes 3 and 4 human HEV.

    Science.gov (United States)

    Sanford, Brenton J; Dryman, Barbara A; Huang, Yao-Wei; Feagins, Alicia R; Leroith, Tanya; Meng, Xiang-Jin

    2011-07-01

    Hepatitis E virus (HEV) is an important human pathogen. At least four recognized and two putative genotypes of mammalian HEV have been reported: genotypes 1 and 2 are restricted to humans whereas genotypes 3 and 4 are zoonotic. The current experimental vaccines are all based on a single strain of HEV, even though multiple genotypes of HEV are co-circulating in some countries and thus an individual may be exposed to more than one genotype. Genotypes 3 and 4 swine HEV is widespread in pigs and known to infect humans. Therefore, it is important to know if prior infection with a genotype 3 swine HEV will confer protective immunity against subsequent exposure to genotypes 3 and 4 human and swine HEV. In this study, specific-pathogen-free pigs were divided into 4 groups of 6 each. Pigs in the three treatment groups were each inoculated with a genotype 3 swine HEV, and 12 weeks later, challenged with the same genotype 3 swine HEV, a genotype 3 human HEV, and a genotype 4 human HEV, respectively. The control group was inoculated and challenged with PBS buffer. Weekly sera from all pigs were tested for HEV RNA and IgG anti-HEV, and weekly fecal samples were also tested for HEV RNA. The pigs inoculated with swine HEV became infected as evidenced by fecal virus shedding and viremia, and the majority of pigs also developed IgG anti-HEV prior to challenge at 12 weeks post-inoculation. After challenge, viremia was not detected and only two pigs challenged with swine HEV had 1-week fecal virus shedding, suggesting that prior infection with a genotype 3 swine HEV prevented pigs from developing viremia and fecal virus shedding after challenges with homologous and heterologous genotypes 3 and 4 HEV. The results from this study have important implications for future development of an effective HEV vaccine. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. The influence of experimental infection of gilts with swine H1N2 influenza A virus during the second month of gestation on the course of pregnancy, reproduction parameters and clinical status

    Science.gov (United States)

    2014-01-01

    Background The course of swine influenza in pigs is reported to be similar to human influenza. Occasionally abortions and other reproduction disorders have been associated with influenza A virus (IAV) infection in pigs. Abortions may be a consequence of high fever, pro-inflammatory cytokines or transplacental transmission of the virus. The role of IAV in the complications observed during pregnancy has been scanty and the true importance of this agent as a cause of reproductive problems in swine is not known. The aim was to determine the possible involvement of swine H1N2 IAV strain on reproductive disorders in pregnant gilts under experimental conditions. Results The gestation length was from 113 to 116 days, no abortion or any other reproduction disorders were noted. A PCR assay confirms the presence of IAV in the nasal swabs taken from inoculated gilts between 1 and 5 dpi. In the nasal swabs from control gilts and newborn piglets, no IAV genetic material was found. No viral RNA was detected in samples of blood taken from gilts and piglets, placentas, lungs and tracheas taken from piglets euthanized after delivery. The significant decrease in the number and percentage of lymphocytes without leukopenia was observed at 4 dpi in inoculated gilts. The percentage of granulocytes increased significantly at 4 dpi in inoculated pigs. The concentration of IL-6, IL-10 and TNF-α were higher in inoculated gilts, while IL-4 and IFN-γ were not detected in the serum of any of animals. The serum concentrations of C-reactive protein remained stable during study, while haptoglobin concentrations increased significantly after inoculation. Conclusions The results of the study indicate that infection of pregnant gilts with swine H1N2 IAV in the second month of pregnancy does not cause abortion and other reproduction disorders. No evidence for transplacental transmission of swine H1N2 IAV was found. However, due to subclinical course of influenza in the present experiment caution

  17. The influence of experimental infection of gilts with swine H1N2 influenza A virus during the second month of gestation on the course of pregnancy, reproduction parameters and clinical status.

    Science.gov (United States)

    Kwit, Krzysztof; Pomorska-Mól, Małgorzata; Markowska-Daniel, Iwona

    2014-06-04

    The course of swine influenza in pigs is reported to be similar to human influenza. Occasionally abortions and other reproduction disorders have been associated with influenza A virus (IAV) infection in pigs. Abortions may be a consequence of high fever, pro-inflammatory cytokines or transplacental transmission of the virus.The role of IAV in the complications observed during pregnancy has been scanty and the true importance of this agent as a cause of reproductive problems in swine is not known. The aim was to determine the possible involvement of swine H1N2 IAV strain on reproductive disorders in pregnant gilts under experimental conditions. The gestation length was from 113 to 116 days, no abortion or any other reproduction disorders were noted. A PCR assay confirms the presence of IAV in the nasal swabs taken from inoculated gilts between 1 and 5 dpi. In the nasal swabs from control gilts and newborn piglets, no IAV genetic material was found. No viral RNA was detected in samples of blood taken from gilts and piglets, placentas, lungs and tracheas taken from piglets euthanized after delivery. The significant decrease in the number and percentage of lymphocytes without leukopenia was observed at 4 dpi in inoculated gilts. The percentage of granulocytes increased significantly at 4 dpi in inoculated pigs. The concentration of IL-6, IL-10 and TNF-α were higher in inoculated gilts, while IL-4 and IFN-γ were not detected in the serum of any of animals. The serum concentrations of C-reactive protein remained stable during study, while haptoglobin concentrations increased significantly after inoculation. The results of the study indicate that infection of pregnant gilts with swine H1N2 IAV in the second month of pregnancy does not cause abortion and other reproduction disorders. No evidence for transplacental transmission of swine H1N2 IAV was found. However, due to subclinical course of influenza in the present experiment caution should be taken in extrapolating

  18. Natural infection of malignant catarrhal fever in Bali cattle: A case study

    Directory of Open Access Journals (Sweden)

    R Damayanti

    2005-06-01

    Full Text Available Malignant catarrhal fever in Indonesia is caused by Ovine herpes virus 2 and considered as a disease with high mortality rate causing degeneratif and lymphoproliferative disease in cattle, buffalo and other ruminants. A total number of fifteen Bali cattle were naturally infected by Malignant Catarrhal Fever (MCF. Those cattle were meant to be experimental animals of research on infectious bovine rhinotracheitis (IBR, Septicaemia epizootica (SE, and bovine brucellosis. The clinical signs of those animals were sudden high fever, depression, anorexia, corneal opacity, mucopurulent oculo-nasal discharges and diarrhoea. Six of them were dead and the remaining cattle were slaughtered at extremis. On the basis of clinical, gross-pathological and histopathological findings, all cases were shown to be consistent and pathognomonic of MCF cases. These cases were regarded as an outbreak of MCF affecting Bali cattle which occurred during wet season and while in other paddock in that area there were a number of lambing sheep. This result confirms that Bali cattle is a very susceptible animal of MCF and the cases were very likely due to the spread of MCF virus from lambing sheep.

  19. USE OF A NEW FORM OF IBUPROFEN IN CHILDREN WITH FEVER AND ACUTE RESPIRATORY TRACT INFECTIONS

    Directory of Open Access Journals (Sweden)

    E. E. Lokshina

    2013-01-01

    Full Text Available Aim: to study clinical efficacy, tolerance and safety of a new pelleted ibuprofen form for children in treatment of fever in patients with acute respiratory tract infection. Patients and methods: children aged from 6 to 12 years old with clinical manifestation of respiratory tract infections and requiring antipyretic treatment were included into the study. Children (n = 50 were administered ibuprofen at a single dose of 5–10 mg/kg of body weight, not more than 3–4 times per day. The efficacy assessment included time needed for temperature decrease (assessment was performed in 15, 30 and 60 minutes and duration of the antipyretic effect (assessment in 6, 8 and 12 hours. Rapidity of analgesic effect in children with ear ache, headache and myalgias was performed in 15, 30, 60 minutes and 6, 8 and 12 hours after the drug intake. Results: antipyretic effect of pelleted ibuprofen for children begins in 15 minutes after its intake. Stable temperature decrease during the first 6 hours was observed in 58% of children (the mean temperature was 37,1 ± 0,3 and maintained up for 12 hours. Relief of pain intensity was established in 62,1% of patients during the first 3 hours, and in 37,9% the pain syndrome was arrested completely. Conclusions: the new pelleted form of ibuprofen for children was proved to have high clinical efficacy and safety in treatment of fever in children with acute respiratory tract infections.

  20. Coxsackie B5 infection in an adult with fever, truncal rash, diarrhea and splenomegaly with highly elevated ferritin levels.

    Science.gov (United States)

    Valestra, Paul K; Fornos, Scarlet Herrarte; Gian, John; Cunha, Burke A

    2016-01-01

    Coxsackie viruses are enteroviruses most common in children. Coxsackie B viral infections often present with biphasic fever, headache, pharyngitis, nausea/vomiting, diarrhea and a maculopapular rash that spares the palms and soles. These clinical features may be present in other viral infections. We present a case of a hospitalized adult with rash and fever with highly elevated ferritin levels later found to be due to Coxsackie B5. We believe this is the first case of Coxsackie B infection with otherwise unexplained highly elevated ferritin levels.

  1. On the mathematical analysis of Ebola hemorrhagic fever: deathly infection disease in West African countries.

    Science.gov (United States)

    Atangana, Abdon; Goufo, Emile Franc Doungmo

    2014-01-01

    For a given West African country, we constructed a model describing the spread of the deathly disease called Ebola hemorrhagic fever. The model was first constructed using the classical derivative and then converted to the generalized version using the beta-derivative. We studied in detail the endemic equilibrium points and provided the Eigen values associated using the Jacobian method. We furthered our investigation by solving the model numerically using an iteration method. The simulations were done in terms of time and beta. The study showed that, for small portion of infected individuals, the whole country could die out in a very short period of time in case there is not good prevention.

  2. Congenital cerebral palsy and prenatal exposure to self-reported maternal infections, fever, or smoking

    DEFF Research Database (Denmark)

    Streja, Elani; Miller, Jessica; Bech, Bodil H

    2013-01-01

    OBJECTIVE: The objective of the study was to investigate the association between maternal self-reported infections, fever, and smoking in the prenatal period and the subsequent risk for congenital cerebral palsy (CP). STUDY DESIGN: We included the 81,066 mothers of singletons born between 1996...... and midgestation. We identified 139 CP cases including 121 cases of spastic CP (sCP) as confirmed by the Danish National Cerebral Palsy Register. Cox proportional hazards regression models were used to estimate adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs). RESULTS: Self-reported vaginal...

  3. AMP-activated kinase restricts Rift Valley fever virus infection by inhibiting fatty acid synthesis.

    Directory of Open Access Journals (Sweden)

    Theresa S Moser

    Full Text Available The cell intrinsic innate immune responses provide a first line of defense against viral infection, and often function by targeting cellular pathways usurped by the virus during infection. In particular, many viruses manipulate cellular lipids to form complex structures required for viral replication, many of which are dependent on de novo fatty acid synthesis. We found that the energy regulator AMPK, which potently inhibits fatty acid synthesis, restricts infection of the Bunyavirus, Rift Valley Fever Virus (RVFV, an important re-emerging arthropod-borne human pathogen for which there are no effective vaccines or therapeutics. We show restriction of RVFV both by AMPK and its upstream activator LKB1, indicating an antiviral role for this signaling pathway. Furthermore, we found that AMPK is activated during RVFV infection, leading to the phosphorylation and inhibition of acetyl-CoA carboxylase, the first rate-limiting enzyme in fatty acid synthesis. Activating AMPK pharmacologically both restricted infection and reduced lipid levels. This restriction could be bypassed by treatment with the fatty acid palmitate, demonstrating that AMPK restricts RVFV infection through its inhibition of fatty acid biosynthesis. Lastly, we found that this pathway plays a broad role in antiviral defense since additional viruses from disparate families were also restricted by AMPK and LKB1. Therefore, AMPK is an important component of the cell intrinsic immune response that restricts infection through a novel mechanism involving the inhibition of fatty acid metabolism.

  4. A super-spreading ewe infects hundreds with Q fever at a farmers' market in Germany

    Directory of Open Access Journals (Sweden)

    Wagner-Wiening Christiane

    2006-10-01

    Full Text Available Abstract Background In May 2003 the Soest County Health Department was informed of an unusually large number of patients hospitalized with atypical pneumonia. Methods In exploratory interviews patients mentioned having visited a farmers' market where a sheep had lambed. Serologic testing confirmed the diagnosis of Q fever. We asked local health departments in Germany to identiy notified Q fever patients who had visited the farmers market. To investigate risk factors for infection we conducted a case control study (cases were Q fever patients, controls were randomly selected Soest citizens and a cohort study among vendors at the market. The sheep exhibited at the market, the herd from which it originated as well as sheep from herds held in the vicinity of Soest were tested for Coxiella burnetii (C. burnetii. Results A total of 299 reported Q fever cases was linked to this outbreak. The mean incubation period was 21 days, with an interquartile range of 16–24 days. The case control study identified close proximity to and stopping for at least a few seconds at the sheep's pen as significant risk factors. Vendors within approximately 6 meters of the sheep's pen were at increased risk for disease compared to those located farther away. Wind played no significant role. The clinical attack rate of adults and children was estimated as 20% and 3%, respectively, 25% of cases were hospitalized. The ewe that had lambed as well as 25% of its herd tested positive for C. burnetii antibodies. Conclusion Due to its size and point source nature this outbreak permitted assessment of fundamental, but seldom studied epidemiological parameters. As a consequence of this outbreak, it was recommended that pregnant sheep not be displayed in public during the 3rd trimester and to test animals in petting zoos regularly for C. burnetii.

  5. Vaccine development for protection against systemic infections with Streptococcus suis and Haemophilus parasuis in swine

    Science.gov (United States)

    Both Streptococcus suis and Haemophilus parasuis are important invasive bacterial pathogens of swine, commonly causing meningitis, arthritis, polyserositis, and septicemia. Due to the presence of many serotypes and high genotypic variability, efficacious vaccines are not readily available. We are us...

  6. Prevalence and risk factors associated with Leptospira spp. infection in technified swine farms in the state of Alagoas, Brazil: risk factors associated with Leptospira spp. in swine farms.

    Science.gov (United States)

    Valença, R M B; Mota, R A; Castro, V; Anderlini, G A; Pinheiro Júnior, J W; Brandespim, D F; Valença, S R F A; Guerra, M M P

    2013-02-01

    The aim of this study was to determine the prevalence and to identify the risk factors associated with Leptospira spp. infection in technified pig farms in the state of Alagoas, Brazil. To compose sample for the prevalence study, 342 pigs were used (312 sows and 30 boars) proceeding from seven swine farms distributed in five districts of the state of Alagoas, Brazil. The infection's serological diagnosis was performed by microscopic agglutination test. The risk factors analysis was performed using research questionnaires consisting of objective questions related to the breeder, the general characteristics of the property, and the productive, reproductive and sanitary management. Prevalence of 16.1% (55/342) of pigs seropositive was obtained. The associated risk factors were not performing quarantine (P = 0.003, OR = 5.43, CI = 1.79-16.41) and the use of artificial insemination (P = 0.023, OR = 3.38, CI = 1.18-9.66). A significant association of sow infection with the increased number of stillborn and mummified foetuses was found, as well as with the increased frequency of oestrus recurrence and the increased weaning-to-oestrus interval of seropositive sows. One might state that Leptospira spp. infection is disseminated in technified pig farms in the State of Alagoas, favouring reproductive failures and the impairment of zootechnical performance in these properties. The risk factors identified in this study are facilitators in the infecting agent dissemination and should be adjusted to control the disease in the herds studied. © 2012 Blackwell Verlag GmbH.

  7. Serological and molecular evidence of hepadnavirus infection in swine

    Directory of Open Access Journals (Sweden)

    Yasmine R Vieira

    2015-02-01

    Full Text Available [b]Introduction and objective[/b]. Recently, investigations in a swine herd identified evidence of the existence of a novel member of the Hepadnavirus family endemic in swine. The aim of this study was to investigate the serological and molecular markers of Hepadnavirus circulation in Brazilian domestic swine and wild boar herds, and to evaluate the identity with HBV and other Hepadnaviruses reported previously. [b]Materials and methods[/b]. For the study, 376 swine were screened for hepatitis B virus serological markers. Analyses were performed in serum samples using commercial enzyme-linked immunosorbent assay (ELISA kits (DiaSorin® for anti-HBc, HBsAg and anti-HBs. Reactive and undetermined swine serum samples were selected to perform DNA viral extraction (QIAamp DNA Mini Kit, Qiagen®, partial genome amplification and genome sequencing. [b]Results[/b]. From 376 swine samples analysed, 28 (7.45% were reactive to anti-HBc, 3 (0.80% to HBsAg and 6 (1.6% to anti-HBs. Besides, more 17 (4.52% swine samples analyzed were classified in the grey zone of the EIA test to anti-HBc and 2 (0.53% to HBsAg. From 49 samples molecularly analyzed after serological trial, 4 samples showed a positive result for the qualitative PCR for Hepadnavirus. Phylogenetic reconstruction using partial genome sequencing (360 bp of 3 samples showed similarity with HBV with 90.8–96.3% of identity. [b]Conclusions.[/b] Serological and molecular data showed evidence of the circulation of a virus similar to hepatitis B virus in swine.

  8. Swine influenza virus vaccine serologic cross-reactivity to contemporary US swine H3N2 and efficacy in pigs infected with an H3N2 similar to 2011-2012 H3N2v.

    Science.gov (United States)

    Kitikoon, Pravina; Gauger, Phillip C; Anderson, Tavis K; Culhane, Marie R; Swenson, Sabrina; Loving, Crystal L; Perez, Daniel R; Vincent, Amy L

    2013-12-01

    Swine influenza A virus (IAV) reassortment with 2009 H1N1 pandemic (H1N1pdm09) virus has been documented, and new genotypes and subclusters of H3N2 have since expanded in the US swine population. An H3N2 variant (H3N2v) virus with the H1N1pdm09 matrix gene and the remaining genes of swine triple reassortant H3N2 caused outbreaks at agricultural fairs in 2011-2012. To assess commercial swine IAV vaccines' efficacy against H3N2 viruses, including those similar to H3N2v, antisera to three vaccines were tested by hemagglutinin inhibition (HI) assay against contemporary H3N2. Vaccine 1, with high HI cross-reactivity, was further investigated for efficacy against H3N2 virus infection in pigs with or without maternally derived antibodies (MDA). In addition, efficacy of a vaccine derived from whole inactivated virus (WIV) was compared with live attenuated influenza virus (LAIV) against H3N2. Hemagglutinin inhibition cross-reactivity demonstrated that contemporary swine H3N2 viruses have drifted from viruses in current swine IAV vaccines. The vaccine with the highest level of HI cross-reactivity significantly protected pigs without MDA. However, the presence of MDA at vaccination blocked vaccine efficacy. The performance of WIV and LAIV was comparable in the absence of MDA. Swine IAV in the United States is complex and dynamic. Vaccination to minimize virus shedding can help limit transmission of virus among pigs and people. However, vaccines must be updated. A critical review of the use of WIV in sows is required in the context of the current IAV ecology and vaccine application in pigs with MDA. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  9. Hepatitis E virus infection in central China reveals no evidence of cross-species transmission between human and swine in this area.

    Directory of Open Access Journals (Sweden)

    Wen Zhang

    Full Text Available Hepatitis E virus (HEV is a zoonotic pathogen of which several species of animal were reported as reservoirs. Swine stands out as the major reservoir for HEV infection in humans, as suggested by the close genetic relationship of swine and human virus. Since 2000, Genotype 4 HEV has become the dominant cause of hepatitis E disease in China. Recent reports showed that genotype 4 HEV is freely transmitted between humans and swine in eastern and southern China. However, the infection status of HEV in human and swine populations in central China is still unclear. This study was conducted in a rural area of central China, where there are many commercial swine farms. A total of 1476 serum and 554 fecal specimens were collected from the general human and swine populations in this area, respectively. The seroepidemiological study was conducted by enzyme-linked immunosorbent assay. Conserved genomic sequences of open reading frame 2 were detected using reverse transcription-PCR. The results indicated that the overall viral burden of the general human subjects was 0.95% (14/1476, while 7.0% (39/554 of the swine excreted HEV in stool. The positive rate of anti-HEV IgG and IgM in the serum samples was 7.9% (117/1476 and 1.6% (24/1476, respectively. Phylogenetic analysis based on the 150 nt partial sequence of the capsid protein gene showed that the 53 swine and human HEV isolates in the current study all belonged to genotype 4, clustering into three major groups. However, the HEV isolates prevalent in the human and swine populations were classified into known distinct subgenotypes, which suggested that no cross-species transmission between swine and humans had taken place in this area. This result was confirmed by cloning and phylogenetic analysis of the complete capsid protein gene sequence of three representative HEV strains in the three major groups. The cross reactivity between anti-HEV IgG from human sera and the two representative strains from swine in

  10. Association of Rift Valley fever virus infection with miscarriage in Sudanese women: a cross-sectional study.

    Science.gov (United States)

    Baudin, Maria; Jumaa, Ammar M; Jomma, Huda J E; Karsany, Mubarak S; Bucht, Göran; Näslund, Jonas; Ahlm, Clas; Evander, Magnus; Mohamed, Nahla

    2016-11-01

    Rift Valley fever virus is an emerging mosquito-borne virus that causes infections in animals and human beings in Africa and the Arabian Peninsula. Outbreaks of Rift Valley fever lead to mass abortions in livestock, but such abortions have not been identified in human beings. Our aim was to investigate the cause of miscarriages in febrile pregnant women in an area endemic for Rift Valley fever. Pregnant women with fever of unknown origin who attended the governmental hospital of Port Sudan, Sudan, between June 30, 2011, and Nov 17, 2012, were sampled at admission and included in this cross-sectional study. Medical records were retrieved and haematological tests were done on patient samples. Presence of viral RNA as well as antibodies against a variety of viruses were analysed. Any association of viral infections, symptoms, and laboratory parameters to pregnancy outcome was investigated using Pearson's χ 2 test. Of 130 pregnant women with febrile disease, 28 were infected with Rift Valley fever virus and 31 with chikungunya virus, with typical clinical and laboratory findings for the infection in question. 15 (54%) of 28 women with an acute Rift Valley fever virus infection had miscarriages compared with 12 (12%) of 102 women negative for Rift Valley fever virus (pInternational Development Cooperation Agency, the County Council of Västerbotten, and the Faculty of Medicine, Umeå University. Copyright © 2016 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY license. Published by Elsevier Ltd.. All rights reserved.

  11. Actinobacillus pleuropneumoniae infections in closed swine herds: infection patterns and serological profiles.

    Science.gov (United States)

    Chiers, Koen; Donné, Eef; Van Overbeke, Ingrid; Ducatelle, Richard; Haesebrouck, Freddy

    2002-04-02

    Many farrow-to-finish herds are endemically infected with Actinobacillus pleuropneumoniae. In order to control the disease efficiently, a better knowledge of the ages at which pigs become infected is necessary. Furthermore, no information is available concerning the influence of maternally derived antibodies on the colonization of the upper respiratory tract. Therefore, A. pleuropneumoniae infection patterns were studied in five farrow-to-finish pig herds (A-E) with a history of pleuropneumonia. A longitudinal study was carried out in herds A and B. In these herds, piglets from sows carrying A. pleuropneumoniae in their noses or tonsils were sampled. Nasal and tonsillar swabs as well as sera, were collected from these animals at the age of 4, 8, 12, 16 (herds A and B) and 23 weeks (herd B). At these ages other pigs from the same sows were euthanized. The lungs were macroscopically examined and samples from nose, tonsils and lungs were collected at necropsy. A cross-sectional study was performed in herds C-E. In these herds nasal and tonsillar swabs, as well as sera, were taken from 10 animals of 4, 8, 12 and 16 weeks of age. Lung, nasal and tonsillar samples were tested for the presence of A. pleuropneumoniae by routine bacteriology and PCR with mixed bacterial cultures. The sera were examined for the presence of Apx toxin neutralizing antibodies. In herd A, A. pleuropneumoniae serotype 2 and 10 strains were isolated, whereas serotype 2, 3, 5b and 8 strains were demonstrated in herd B. In most herds, A. pleuropneumoniae was detected in mixed bacterial cultures of tonsillar and/or nasal samples by PCR from the age of 4 weeks onwards. Colonization of the lungs and development of lung lesions was observed in 12- and 16-week-old animals of herd A and 23-week-old animals of herd B. In most herds, high antibody titres were detected in 4-week-old piglets. These titres decreased during the first 12 weeks of age, but thereafter, increased. It was concluded that PCR with

  12. Qualitative risk assessment in a data-scarce environment: a model to assess the impact of control measures on spread of African Swine Fever.

    Science.gov (United States)

    Wieland, Barbara; Dhollander, Sofie; Salman, Mo; Koenen, Frank

    2011-04-01

    In the absence of data, qualitative risk assessment frameworks have proved useful to assess risks associated with animal health diseases. As part of a scientific opinion for the European Commission (EC) on African Swine Fever (ASF), a working group of the European Food Safety Authority (EFSA) assessed the risk of ASF remaining endemic in Trans Caucasus Countries (TCC) and the Russian Federation (RF) and the risk of ASF becoming endemic in the EU if disease were introduced. The aim was to develop a tool to evaluate how current control or preventive measures mitigate the risk of spread and giving decision makers the means to review how strengthening of surveillance and control measures would mitigate the risk of disease spread. Based on a generic model outlining disease introduction, spread and endemicity in a region, the impact of risk mitigation measures on spread of disease was assessed for specific risk questions. The resulting hierarchical models consisted of key steps containing several sub-steps. For each step of the risk pathways risk estimates were determined by the expert group based on existing data or through expert opinion elicitation. Risk estimates were combined using two different combination matrices, one to combine estimates of independent steps and one to combine conditional probabilities. The qualitative risk assessment indicated a moderate risk that ASF will remain endemic in current affected areas in the TCC and RF and a high risk of spread to currently unaffected areas. If introduced into the EU, ASF is likely to be controlled effectively in the production sector with high or limited biosecurity. In the free range production sector, however, there is a moderate risk of ASF becoming endemic due to wild boar contact, non-compliance with animal movement bans, and difficult access to all individual pigs upon implementation of control measures. This study demonstrated the advantages of a systematic framework to assist an expert panel to carry out a

  13. Qualitative analysis of the risks and practices associated with the spread of African swine fever within the smallholder pig value chains in Uganda.

    Science.gov (United States)

    Dione, Michel; Ouma, Emily; Opio, Felix; Kawuma, Brian; Pezo, Danilo

    2016-12-01

    A study was undertaken between September 2014 and December 2014 to assess the perceptions of smallholder pig value chain actors of the risks and practices associated with the spread of African swine fever (ASF) disease within the pig value chains. Data was collected from 136 value chain actors and 36 key informants through 17 group discussions and two key informant interview (KII) sessions respectively using Participatory Rural Appraisal (PRA) tools. Results from this study revealed that according to value chain actors and stakeholders, the transporting, slaughtering, and collecting/bulking nodes represent the highest risk, followed by the inputs and services (feeds and drugs) supply nodes. The processing, whole sale and consumption nodes represented the lowest risk. Value chain actors are aware of the disease and its consequences to the pig industry, however biosecurity measures are poorly implemented at all nodes. As for the causes, value chain actors pointed to several factors, such as inadequate knowledge of mechanisms for the spread of the disease, poor enforcement of regulations on disease control, and low capacities of actors to implement biosecurity measures, amongst others. Although traders, butchers and veterinary practitioners accepted that they played an important role in the spread of the virus, they did not perceive themselves as key actors in the control of the disease; instead, they believed that only farmers should adopt biosecurity measures on their farms because they keep the pigs for a longer period. Most of the recommendations given by the value chain actors for controlling and preventing ASF disease were short term, and targeted mainly pig producers. These recommendations included: the establishment of live pig collection centres so that traders and brokers do not have to directly access pig farms, capacity building of value chain actors on application of biosecurity, enactment and enforcement of by-laws on live pig movements and establishment

  14. Yellow Fever 17DD Vaccine Virus Infection Causes Detectable Changes in Chicken Embryos

    Science.gov (United States)

    Manso, Pedro Paulo de Abreu; Dias de Oliveira, Barbara C. E. P.; de Sequeira, Patrícia Carvalho; Maia de Souza, Yuli Rodrigues; Ferro, Jessica Maria dos Santos; da Silva, Igor José; Caputo, Luzia Fátima Gonçalves; Guedes, Priscila Tavares; dos Santos, Alexandre Araujo Cunha; Freire, Marcos da Silva; Bonaldo, Myrna Cristina; Pelajo-Machado, Marcelo

    2015-01-01

    The yellow fever (YF) 17D vaccine is one of the most effective human vaccines ever created. The YF vaccine has been produced since 1937 in embryonated chicken eggs inoculated with the YF 17D virus. Yet, little information is available about the infection mechanism of YF 17DD virus in this biological model. To better understand this mechanism, we infected embryos of Gallus gallus domesticus and analyzed their histopathology after 72 hours of YF infection. Some embryos showed few apoptotic bodies in infected tissues, suggesting mild focal infection processes. Confocal and super-resolution microscopic analysis allowed us to identify as targets of viral infection: skeletal muscle cells, cardiomyocytes, nervous system cells, renal tubular epithelium, lung parenchyma, and fibroblasts associated with connective tissue in the perichondrium and dermis. The virus replication was heaviest in muscle tissues. In all of these specimens, RT-PCR methods confirmed the presence of replicative intermediate and genomic YF RNA. This clearer characterization of cell targets in chicken embryos paves the way for future development of a new YF vaccine based on a new cell culture system. PMID:26371874

  15. Airport sentinel surveillance and entry quarantine for dengue infections following a fever screening program in Taiwan.

    Science.gov (United States)

    Kuan, Mei-Mei; Chang, Feng-Yee

    2012-08-06

    Dengue has not reached an endemic status in Taiwan; nevertheless, we have implemented a fever screening program at airports for the early detection of febrile passengers with a dengue infection. This study is intended to assess the performance of the airport screening procedures for dengue infection. We analyzed data from the national surveillance system of the Taiwan Centers for Disease Control. We included the imported dengue cases reported by sentinel airports and clinics as well as the domestic cases from 2007-2010. Approximately 44.9% (95%CI: 35.73-54.13%) of the confirmed imported dengue cases with an apparent symptom (febrile) in the viremic stage were detected via the airport fever screening program, with an estimated positive predictive value of 2.36% (95% CI: 0.96- 3.75%) and a negative predictive value > 99.99%. Fluctuations in the number of the symptomatic imported dengue cases identified in the airports (X) were associated with the total number of imported dengue cases (Y) based on a regression analysis of a biweekly surveillance (i.e., n = 104, R(2)(X:Y) = 0.61, P airports examined in this study indicated some limitations of the fever screening program for the prevention of importation. The screening program could assist in the rapid triage for self-quarantine of some symptomatic dengue cases that were in the viremic stage at the borders and contribute to active sentinel surveillance; however, the blocking of viral transmission to susceptible populations (neighbors or family) from all of the viremic travelers, including those with or without symptoms, is critical to prevent dengue epidemics. Therefore, the reinforcement of mosquito bite prevention and household vector control in dengue-endemic or dengue-competent hotspots during an epidemic season is essential and highly recommended.

  16. Insights into Borrelia miyamotoi infection from an untreated case demonstrating relapsing fever, monocytosis and a positive C6 Lyme serology.

    Science.gov (United States)

    Sudhindra, Praveen; Wang, Guiqing; Schriefer, Martin E; McKenna, Donna; Zhuge, Jian; Krause, Peter J; Marques, Adriana R; Wormser, Gary P

    2016-09-01

    We describe a patient from the United States with PCR- and serology-confirmed Borrelia miyamotoi infection who recovered without antibiotics. Our findings suggest that B. miyamotoi infection may cause relapsing fever, blood monocytosis and antibody reactivity to the C6 peptide. Further studies are required to better define the spectrum of clinical and laboratory findings for this emerging tick-transmitted infection. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. A longitudinal study of serological patterns of respiratory infections in nine infected Danish swine herds

    DEFF Research Database (Denmark)

    Andreasen, Margit; Nielsen, Jens; Bækbo, Poul

    2000-01-01

    Sixteen litters of seven pigs from each of nine Danish farrow-to-finish herds were followed to investigate the serological patterns caused by natural infection with Mycoplasma hyponeumoniae, Pasteurella multocida toxin and Actinobacillus pleuroneumoniae serotypes 2, 5-7, 12. In seven of the herds....... hyopneumoniae (enzyme-linked immunosorbent assay), P. multocida toxin (enzyme-linked immunosorbent assay) and A. pleuropneumoniae serotypes 2, 5-7, 12 (complement-fixation tests). The most-common pattern (28%) of seroconversion was that of pigs first seroconverting to A. pleuropneumoniae serotype 2, followed...... by seroconversion to M. hyopneumoniae. Each herd had a dominant serotype of A. pleuropneumoniae to which most pigs seroconverted. Seroconversion to the respiratory pathogens occurred mainly in the growing-to-finishing units (8-24 weeks). The risk of seroconversion to the P. multocida toxin was very low (...

  18. A longitudinal study of serological patterns of respiratory infections in nine infected Danish swine herds

    DEFF Research Database (Denmark)

    Andreasen, Margit; Nielsen, Jens; Bækbo, Poul

    2000-01-01

    Sixteen litters of seven pigs from each of nine Danish farrow-to-finish herds were followed to investigate the serological patterns caused by natural infection with Mycoplasma hyponeumoniae, Pasteurella multocida toxin and Actinobacillus pleuroneumoniae serotypes 2, 5-7, 12. In seven of the herds......, pigs were followed as two separate cohorts started 4 weeks apart, and in two herds only one cohort was followed. A total of 999 pigs were included in the study. The pigs were blood sampled at weaning and subsequently every fourth week until slaughter. All pigs were examined for antibodies against M....... hyopneumoniae (enzyme-linked immunosorbent assay), P. multocida toxin (enzyme-linked immunosorbent assay) and A. pleuropneumoniae serotypes 2, 5-7, 12 (complement-fixation tests). The most-common pattern (28%) of seroconversion was that of pigs first seroconverting to A. pleuropneumoniae serotype 2, followed...

  19. The use of infrared thermography as a non-invasive method for fever detection in sheep infected with bluetongue virus.

    Science.gov (United States)

    Pérez de Diego, Ana C; Sánchez-Cordón, Pedro J; Pedrera, Miriam; Martínez-López, Beatriz; Gómez-Villamandos, José C; Sánchez-Vizcaíno, José M

    2013-10-01

    Fever, which is closely linked to viraemia, is considered to be both the main and the earliest clinical sign in sheep infected with bluetongue virus (BTV). The aim of this study was to evaluate the potential use of infrared thermography (IRT) for early detection of fever in sheep experimentally infected with bluetongue virus serotype 1 (BTV-1) and serotype 8 (BTV-8). This would reduce animal stress during experimental assays and assist in the development of a screening method for the identification of fever in animals suspected of being infected with BTV. Rectal and infrared eye temperatures were collected before and after BTV inoculation. The two temperature measures were positively correlated (r=0.504, Pinfrared temperatures was observed when temperatures were above physiological levels. IRT discriminated between febrile and non-febrile sheep with a sensitivity of 85% and specificity of 97%. The results showed that eye temperature measured using IRT was a useful non-invasive method for the assessment of fever in sheep infected with BTV under experimental conditions. Further research is required to evaluate the use of IRT under field conditions to identify potentially infected animals in bluetongue surveillance programmes. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Investigation of Pathogenesis of H1N1 Influenza Virus and Swine Streptococcus suis Serotype 2 Co-Infection in Pigs by Microarray Analysis.

    Directory of Open Access Journals (Sweden)

    Xian Lin

    Full Text Available Swine influenza virus and Streptococcus suis are two important contributors to the porcine respiratory disease complex, and both have significant economic impacts. Clinically, influenza virus and Streptococcus suis co-infections in pigs are very common, which often contribute to severe pneumonia and can increase the mortality. However, the co-infection pathogenesis in pigs is unclear. In the present study, co-infection experiments were performed using swine H1N1 influenza virus and Streptococcus suis serotype 2 (SS2. The H1N1-SS2 co-infected pigs exhibited more severe clinical symptoms, serious pathological changes, and robust apoptosis of lungs at 6 days post-infection compared with separate H1N1 and SS2 infections. A comprehensive gene expression profiling using a microarray approach was performed to investigate the global host responses of swine lungs against the swine H1N1 infection, SS2 infection, co-infection, and phosphate-buffered saline control. Results showed 457, 411, and 844 differentially expressed genes in the H1N1, SS2, and H1N1-SS2 groups, respectively, compared with the control. Noticeably, genes associated with the immune, inflammatory, and apoptosis responses were highly overexpressed in the co-infected group. Pathway analysis indicated that the cytokine-cytokine receptor interactions, MAPK, toll-like receptor, complement and coagulation cascades, antigen processing and presentation, and apoptosis pathway were significantly regulated in the co-infected group. However, the genes related to these were less regulated in the separate H1N1 and SS2 infection groups. This observation suggested that a certain level of synergy was induced by H1N1 and SS2 co-infection with significantly stronger inflammatory and apoptosis responses, which may lead to more serious respiratory disease syndrome and pulmonary pathological lesion.

  1. Investigation of Pathogenesis of H1N1 Influenza Virus and Swine Streptococcus suis Serotype 2 Co-Infection in Pigs by Microarray Analysis.

    Science.gov (United States)

    Lin, Xian; Huang, Canhui; Shi, Jian; Wang, Ruifang; Sun, Xin; Liu, Xiaokun; Zhao, Lianzhong; Jin, Meilin

    2015-01-01

    Swine influenza virus and Streptococcus suis are two important contributors to the porcine respiratory disease complex, and both have significant economic impacts. Clinically, influenza virus and Streptococcus suis co-infections in pigs are very common, which often contribute to severe pneumonia and can increase the mortality. However, the co-infection pathogenesis in pigs is unclear. In the present study, co-infection experiments were performed using swine H1N1 influenza virus and Streptococcus suis serotype 2 (SS2). The H1N1-SS2 co-infected pigs exhibited more severe clinical symptoms, serious pathological changes, and robust apoptosis of lungs at 6 days post-infection compared with separate H1N1 and SS2 infections. A comprehensive gene expression profiling using a microarray approach was performed to investigate the global host responses of swine lungs against the swine H1N1 infection, SS2 infection, co-infection, and phosphate-buffered saline control. Results showed 457, 411, and 844 differentially expressed genes in the H1N1, SS2, and H1N1-SS2 groups, respectively, compared with the control. Noticeably, genes associated with the immune, inflammatory, and apoptosis responses were highly overexpressed in the co-infected group. Pathway analysis indicated that the cytokine-cytokine receptor interactions, MAPK, toll-like receptor, complement and coagulation cascades, antigen processing and presentation, and apoptosis pathway were significantly regulated in the co-infected group. However, the genes related to these were less regulated in the separate H1N1 and SS2 infection groups. This observation suggested that a certain level of synergy was induced by H1N1 and SS2 co-infection with significantly stronger inflammatory and apoptosis responses, which may lead to more serious respiratory disease syndrome and pulmonary pathological lesion.

  2. Investigation of Pathogenesis of H1N1 Influenza Virus and Swine Streptococcus suis Serotype 2 Co-Infection in Pigs by Microarray Analysis

    Science.gov (United States)

    Shi, Jian; Wang, Ruifang; Sun, Xin; Liu, Xiaokun; Zhao, Lianzhong; Jin, Meilin

    2015-01-01

    Swine influenza virus and Streptococcus suis are two important contributors to the porcine respiratory disease complex, and both have significant economic impacts. Clinically, influenza virus and Streptococcus suis co-infections in pigs are very common, which often contribute to severe pneumonia and can increase the mortality. However, the co-infection pathogenesis in pigs is unclear. In the present study, co-infection experiments were performed using swine H1N1 influenza virus and Streptococcus suis serotype 2 (SS2). The H1N1-SS2 co-infected pigs exhibited more severe clinical symptoms, serious pathological changes, and robust apoptosis of lungs at 6 days post-infection compared with separate H1N1 and SS2 infections. A comprehensive gene expression profiling using a microarray approach was performed to investigate the global host responses of swine lungs against the swine H1N1 infection, SS2 infection, co-infection, and phosphate-buffered saline control. Results showed 457, 411, and 844 differentially expressed genes in the H1N1, SS2, and H1N1-SS2 groups, respectively, compared with the control. Noticeably, genes associated with the immune, inflammatory, and apoptosis responses were highly overexpressed in the co-infected group. Pathway analysis indicated that the cytokine–cytokine receptor interactions, MAPK, toll-like receptor, complement and coagulation cascades, antigen processing and presentation, and apoptosis pathway were significantly regulated in the co-infected group. However, the genes related to these were less regulated in the separate H1N1 and SS2 infection groups. This observation suggested that a certain level of synergy was induced by H1N1 and SS2 co-infection with significantly stronger inflammatory and apoptosis responses, which may lead to more serious respiratory disease syndrome and pulmonary pathological lesion. PMID:25906258

  3. High occurrence of Mycoplasma suis infection in swine herds from non-technified farms in Mossoró, state of Rio Grande do Norte, Northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Mariana Aparecida Toledo

    Full Text Available Abstract Mycoplasma suis, the etiological agent of swine hemoplasmosis, has been neglected in swine herds around the world. Swine hemoplasmosis is frequently associated with hemolytic anemia, disgalacty, infertility and immunosuppression, and it results in significant economic losses. This study investigates the occurrence of M. suis in non-technified swine herds in the northeastern region of Brazil using quantitative PCR (qPCR based on the 16S rRNA gene. Between March and August 2013, blood samples from 147 swine were collected during slaughter in the city of Mossoró, state of Rio Grande do Norte, northeastern Brazil. One hundred and twelve samples (76.19% were positive for M. suis by qPCR assays. The range of Cqs and quantification (copies of a M. suis-16S rRNA gene fragment/µL was 20.86–37.89 and 1.64×101–6.64×107, respectively. One can conclude that M. suis infection have high occurrence (76,19% in non-technified swine-rearing systems in Mossoró in the state of Rio Grande do Norte, Brazil.

  4. Body temperature changes during simulated bacterial infection in a songbird: fever at night and hypothermia during the day.

    Science.gov (United States)

    Sköld-Chiriac, Sandra; Nord, Andreas; Tobler, Michael; Nilsson, Jan-Åke; Hasselquist, Dennis

    2015-09-01

    Although fever (a closely regulated increase in body temperature in response to infection) typically is beneficial, it is energetically costly and may induce detrimentally high body temperatures. This can increase the susceptibility to energetic bottlenecks and risks of overheating in some organisms. Accordingly, it could be particularly interesting to study fever in small birds, which have comparatively high metabolic rates and high, variable body temperatures. We therefore investigated two aspects of fever and other sickness behaviours (circadian variation, dose dependence) in a small songbird, the zebra finch. We injected lipopolysaccharide (LPS) at the beginning of either the day or the night, and subsequently monitored body temperature, body mass change and food intake for the duration of the response. We found pronounced circadian variation in the body temperature response to LPS injection, manifested by (dose-dependent) hypothermia during the day but fever at night. This resulted in body temperature during the peak response being relatively similar during the day and night. Day-to-night differences might be explained in the context of circadian variation in body temperature: songbirds have a high daytime body temperature that is augmented by substantial heat production peaks during activity. This might require a trade-off between the benefit of fever and the risk of overheating. In contrast, at night, when body temperature is typically lower and less variable, fever can be used to mitigate infection. We suggest that the change in body temperature during infection in small songbirds is context dependent and regulated to promote survival according to individual demands at the time of infection. © 2015. Published by The Company of Biologists Ltd.

  5. High frequency of hepatitis E virus infection in swine from South Brazil and close similarity to human HEV isolates

    Directory of Open Access Journals (Sweden)

    Ana Maria Passos-Castilho

    Full Text Available Abstract Hepatitis E virus is responsible for acute and chronic liver infections worldwide. Swine hepatitis E virus has been isolated in Brazil, and a probable zoonotic transmission has been described, although data are still scarce. The aim of this study was to investigate the frequency of hepatitis E virus infection in pigs from a small-scale farm in the rural area of Paraná State, South Brazil. Fecal samples were collected from 170 pigs and screened for hepatitis E virus RNA using a duplex real-time RT-PCR targeting a highly conserved 70 nt long sequence within overlapping parts of ORF2 and ORF3 as well as a 113 nt sequence of ORF2. Positive samples with high viral loads were subjected to direct sequencing and phylogenetic analysis. hepatitis E virus RNA was detected in 34 (20.0% of the 170 pigs following positive results in at least one set of screening real-time RT-PCR primers and probes. The swine hepatitis E virus strains clustered with the genotype hepatitis E virus-3b reference sequences in the phylogenetic analysis and showed close similarity to human hepatitis E virus isolates previously reported in Brazil.

  6. Dengue hemorrhagic fever: comparison of patients with primary and secondary infections.

    Science.gov (United States)

    Khurram, Muhammad; Qayyum, Wajeeha; Hassan, Syed Jawad Ul; Mumtaz, Shamaila; Bushra, Hamama Tul; Umar, Muhammad

    2014-01-01

    Dengue hemorrhagic fever (DHF) is considered to be associated with secondary dengue infection. This study was conducted to note frequency of primary and secondary dengue infection in DHF patients. Additionally these patients were compared in terms of age, gender, laboratory parameter, diseases severity and outcome. In this cross sectional observational study DHF patients fulfilling DHF criteria of Dengue Expert Advisory Group (DEAG) were included and divided into groups based on dengue specific IgG positivity and ratio of IgM to IgG. Group I, patients with secondary dengue infection were IgG positive or their ratio of IgM to IgG was dengue infection patients were IgG negative or their ratio of IgM to IgG was >1.2. The two Groups were compared for statistically significant association in terms of age, gender, laboratory parameter (at admission hematocrit [HCT], platelet, white blood cell [WBC] counts, alanine aminotransferase [ALT] value), severity (DHF or dengue shock syndrome), and outcome (recovered or expired). Two hundred thirty-four DHF patients were included. 66.2% was male and 33.8% female. Mean patient age was 28.8 ± 12.4 years. Based on dengue markers results, 61.5% patients were categorized to Group I, and 38.5% to Group II. Statistically significant association between the two Groups was noted in terms of at admission platelet count, and ALT value, P value dengue infection is frequently associated with DHF. Patients with DHF caused by secondary dengue infection have lower at admission platelet counts and higher ALT value. Copyright © 2014 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

  7. In vitro and ex vivo analyses of co-infections with swine influenza and porcine reproductive and respiratory syndrome viruses.

    Science.gov (United States)

    Dobrescu, I; Levast, B; Lai, K; Delgado-Ortega, M; Walker, S; Banman, S; Townsend, H; Simon, G; Zhou, Y; Gerdts, V; Meurens, F

    2014-02-21

    Viral respiratory diseases remain problematic in swine. Among viruses, porcine reproductive and respiratory syndrome virus (PRRSV) and swine influenza virus (SIV), alone or in combination, are the two main known contributors to lung infectious diseases. Previous studies demonstrated that experimental dual infections of pigs with PRRSV followed by SIV can cause more severe disease than the single viral infections. However, our understanding of the impact of one virus on the other at the molecular level is still extremely limited. Thus, the aim of the current study was to determine the influence of dual infections, compared to single infections, in porcine alveolar macrophages (PAMs) and precision cut lung slices (PCLS). PAMs were isolated and PCLS were acquired from the lungs of healthy 8-week-old pigs. Then, PRRSV (ATCC VR-2385) and a local SIV strain of H1N1 subtype (A/Sw/Saskatchewan/18789/02) were applied simultaneously or with 3h apart on PAMs and PCLS for a total of 18 h. Immuno-staining for both viruses and beta-tubulin, real-time quantitative PCR and ELISA assays targeting various genes (pathogen recognition receptors, interferons (IFN) type I, cytokines, and IFN-inducible genes) and proteins were performed to analyze the cell and the tissue responses. Interference caused by the first virus on replication of the second virus was observed, though limited. On the host side, a synergistic effect between PRRSV and SIV co-infections was observed for some transcripts such as TLR3, RIG-I, and IFNβ in PCLS. The PRRSV infection 3h prior to SIV infection reduced the response to SIV while the SIV infection prior to PRRSV infection had limited impact on the second infection. This study is the first to show an impact of PRRSV/SIV co-infection and superinfections in the cellular and tissue immune response at the molecular level. It opens the door to further research in this exciting and intriguing field. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. [Rift Valley fever: sporadic infection of French military personnel outside currently recognized epidemic zones].

    Science.gov (United States)

    Durand, J P; Richecoeur, L; Peyrefitte, C; Boutin, J P; Davoust, B; Zeller, H; Bouloy, M; Tolou, H

    2002-01-01

    For three years the arbovirus surveillance unit of the Tropical Medicine Institute of the French Army Medical Corps (French acronym IMTSSA) in Marseille, France has been investigating causes of benign non-malarial febrile syndromes in French military personnel serving outside mainland France. The methodology used in N'Djamena consisted of sending frozen specimens collected concomitant with viremia, to Marseille for culture. During the rainy season of 2001, specimens were collected from a total of 50 febrile soldiers. Cultures allowed isolation and identification of two strains of Rift Valley virus. The risk of contamination exists not only in the field but also in mainland hospital departments treating infected patients. Routine serological diagnosis for Rift Valley fever must be DISCUSSED for all patients in the field or returning from Africa.

  9. IGG Subclass and Isotype Specific Immunoglobulin Responses to LASSA fever and Venezuelan Equine Encephalomyelitis: Natural Infection and Immunication

    Science.gov (United States)

    1989-03-01

    produced by serial passage of the wild virus utilizing guinea pig fetal heart cell culture, has proved to be efficacious (providing long term...VENEZUELAN EQUINE ENCEPHALOMYELITIS : NATURAL INFECTION AND IMMUNIZATION PRINCIPAL INVESTIGATOR: Renata J. Engler CONTRACTING ORGANIZATION: Uniformed Services...TITLE (include Security Classification) IGG SUBCLASS & ISOTYPE SPECIFIC IMMUNOGLOBULIN RESPONSES TO LASSA FEVER & VENEZUELAN EQUINE ENCEPHALOMYELITIS

  10. Screening of post-mortem tissue donors for Coxiella burnetii infection after large outbreaks of Q fever in The Netherlands

    NARCIS (Netherlands)

    van Wijk, Marja J.; Maas, D. Willemijn; Renders, Nicole H. M.; Hermans, Mirjam H. A.; Zaaijer, Hans L.; Hogema, Boris M.

    2014-01-01

    After the largest outbreaks of Q fever ever recorded in history occurred in the Netherlands, concern arose that Coxiella may be transmitted via donated tissues of latent or chronically infected donors. The Dutch Health Council recently advised to screen tissue donors, donating high risk tissues, for

  11. Identification of a major non-structural protein in the nuclei of Rift Valley fever virus-infected cells.

    Science.gov (United States)

    Struthers, J K; Swanepoel, R

    1982-06-01

    A non-structural protein of mol. wt. 34 X 10(3) was demonstrated in the nuclei of Rift Valley fever virus-infected Vero cells by SDS-polyacrylamide gel electro-phoresis. The protein appears to correspond to the virus-induced antigen demonstrated by indirect immunofluorescence in intranuclear inclusions.

  12. Zika virus infection, associated microcephaly, and low yellow fever vaccination coverage in Brazil: is there any causal link?

    Science.gov (United States)

    De Góes Cavalcanti, Luciano Pamplona; Tauil, Pedro Luiz; Alencar, Carlos Henrique; Oliveira, Wanderson; Teixeira, Mauro Martins; Heukelbach, Jorg

    2016-06-30

    Since the end of 2014, Zika virus (ZIKV) infection has been rapidly spreading in Brazil. To analyze the possible association of yellow fever vaccine with a protective effect against ZIKV-related microcephaly, the following spatial analyses were performed, using Brazilian municipalities as units: i) yellow fever vaccination coverage in Brazilian municipalities in individuals aged 15-49; ii) reported cases of microcephaly by municipality; and iii) confirmed cases of microcephaly related to ZIKV, by municipality. SaTScan software was used to identify clusters of municipalities for high risk of microcephaly. There were seven significant high risk clusters of confirmed microcephaly cases, with four of them located in the Northeast where yellow fever vaccination rates were the lowest. The clusters harbored only 2.9% of the total population of Brazil, but 15.2% of confirmed cases of microcephaly. We hypothesize that pregnant women in regions with high yellow fever vaccination coverage may pose their offspring to lower risk for development of microcephaly. There is an urgent need for systematic studies to confirm the possible link between low yellow fever vaccination coverage, Zika virus infection and microcephaly.

  13. Stability Analysis Susceptible, Exposed, Infected, Recovered (SEIR) Model for Spread Model for Spread of Dengue Fever in Medan

    Science.gov (United States)

    Side, Syafruddin; Molliq Rangkuti, Yulita; Gerhana Pane, Dian; Setia Sinaga, Marlina

    2018-01-01

    Dengue fever is endemic disease which spread through vector, Aedes Aegypty. This disease is found more than 100 countries, such as, United State, Africa as well Asia, especially in country that have tropic climate. Mathematical modeling in this paper, discusses the speed of the spread of dengue fever. The model adopting divided over four classes, such as Susceptible (S), Exposed (E), Infected (I) and Recovered (R). SEIR model further analyzed to detect the re-breeding value based on the number reported case by dengue in Medan city. Analysis of the stability of the system in this study is asymptotically stable indicating a case of endemic and unstable that show cases the endemic cases. Simulation on the mathematical model of SEIR showed that require a very long time to produce infected humans will be free of dengue virus infection. This happens because of dengue virus infection that occurs continuously between human and vector populations.

  14. Airport sentinel surveillance and entry quarantine for dengue infections following a fever screening program in Taiwan

    Science.gov (United States)

    2012-01-01

    Background Dengue has not reached an endemic status in Taiwan; nevertheless, we have implemented a fever screening program at airports for the early detection of febrile passengers with a dengue infection. This study is intended to assess the performance of the airport screening procedures for dengue infection. Methods We analyzed data from the national surveillance system of the Taiwan Centers for Disease Control. We included the imported dengue cases reported by sentinel airports and clinics as well as the domestic cases from 2007–2010. Results Approximately 44.9% (95%CI: 35.73-54.13%) of the confirmed imported dengue cases with an apparent symptom (febrile) in the viremic stage were detected via the airport fever screening program, with an estimated positive predictive value of 2.36% (95% CI: 0.96- 3.75%) and a negative predictive value > 99.99%. Fluctuations in the number of the symptomatic imported dengue cases identified in the airports (X) were associated with the total number of imported dengue cases (Y) based on a regression analysis of a biweekly surveillance (i.e., n = 104, R2X:Y = 0.61, P dengue cases (X) with a 1–2 month lead time (t) was in parallel with that of the domestic dengue cases (Y) based on a consecutive 4-year surveillance (i.e., n = 48, R2X(t-1):Y = 0.22, R2X(t-2):Y = 0.31, P dengue at the airports examined in this study indicated some limitations of the fever screening program for the prevention of importation. The screening program could assist in the rapid triage for self-quarantine of some symptomatic dengue cases that were in the viremic stage at the borders and contribute to active sentinel surveillance; however, the blocking of viral transmission to susceptible populations (neighbors or family) from all of the viremic travelers, including those with or without symptoms, is critical to prevent dengue epidemics. Therefore, the reinforcement of mosquito bite prevention and household vector control in

  15. Variant (Swine Origin) Influenza Viruses in Humans

    Science.gov (United States)

    ... Types Seasonal Avian Swine Variant Other Variant Influenza Viruses: Background and CDC Risk Assessment and Reporting Language: ... Background CDC Assessment Reporting Background On Variant Influenza Viruses Swine flu viruses do not normally infect humans. ...

  16. Family Cluster Analysis of Severe Fever with Thrombocytopenia Syndrome Virus Infection in Korea.

    Science.gov (United States)

    Yoo, Jeong Rae; Heo, Sang Taek; Park, Dahee; Kim, Hyemin; Fukuma, Aiko; Fukushi, Shuetsu; Shimojima, Masayuki; Lee, Keun Hwa

    2016-12-07

    Severe fever with thrombocytopenia syndrome (SFTS) is tick-borne viral disease that was first suspected in China in 2009. The causative virus (SFTSV) was isolated in 2009 and reported in 2011, and SFTSV expanded its geographic distribution in 2012-2013, from China to South Korea and Japan. Most SFTSV infections occur through Haemaphysalis longicornis However, SFTSV infection can also occur between family members, and nosocomial transmission of SFTSV is also possible through close contact with a patient. In this study, we first analyzed clinical, epidemiological, and laboratory data for SFTS patients and family members of an index patient in Korea. The S segment of SFTSV was amplified from the sera of three patients, and the S segment of SFTSV and IgG specific to SFTSV were detected in the serum from one family member; although this individual had no history of exposure to H. longicornis, she frequently had close contact with the index patient. In Korea, SFTSV infection among family members does not have to be reported, and we suggest that person-to-person transmission of SFTSV among family members is possible in Korea. © The American Society of Tropical Medicine and Hygiene.

  17. Outbreak of swine-origin influenza A (H1N1) virus infection - Mexico, March-April 2009.

    Science.gov (United States)

    2009-05-08

    In March and early April 2009, Mexico experienced outbreaks of respiratory illness and increased reports of patients with influenza-like illness (ILI) in several areas of the country. On April 12, the General Directorate of Epidemiology (DGE) reported an outbreak of ILI in a small community in the state of Veracruz to the Pan American Health Organization (PAHO) in accordance with International Health Regulations. On April 17, a case of atypical pneumonia in Oaxaca State prompted enhanced surveillance throughout Mexico. On April 23, several cases of severe respiratory illness laboratory confirmed as swine-origin influenza A (H1N1) virus (S-OIV) infection were communicated to the PAHO. Sequence analysis revealed that the patients were infected with the same S-OIV strain detected in two children residing in California. This report describes the initial and ongoing investigation of the S-OIV outbreak in Mexico.

  18. 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.

  19. Chikungunya fever: CNS infection and pathologies of a re-emerging arbovirus.

    Science.gov (United States)

    Das, Trina; Jaffar-Bandjee, Marie Christine; Hoarau, Jean Jacques; Krejbich Trotot, Pascale; Denizot, Melanie; Lee-Pat-Yuen, Ghislaine; Sahoo, Renubala; Guiraud, Pascale; Ramful, Duksha; Robin, Stephanie; Alessandri, Jean Luc; Gauzere, Bernard Alex; Gasque, Philippe

    2010-06-01

    Chikungunya virus (CHIKV) is transmitted by Aedes mosquitoes and causes an acute symptomatic illness with fever, skin rash, and incapacitating arthralgia, which can evolve into chronic rheumatoid arthritis in elderly patients. This is a tropical disease originally described in central/east Africa in the 1960s, but its 2004 re-emergence in Africa and rapid spread in lands in and around the Indian Ocean (Reunion island, India, Malaysia) as well as Europe (Italy) led to almost 6 million cases worldwide. The risk of importation and spreading diseases with long-term sequelae is even greater today given the global distribution of the vectors (including in the Americas), increased tourism and the apparent capacity of CHIKV to produce high levels of viremia (10(9)-10(12) virus/ml of blood) and new mutants. CHIKV-associated neuropathology was described early in the 1960s, but it is the unprecedented incidence rate in Indian Ocean areas with efficient clinical facilities that allowed a better description of cases with severe encephalitis, meningoencephalitis, peripheral neuropathies and deaths among newborns (mother-to-child infection), infants and elderly patients. Death rates following CHIKV infection were estimated at 1:1000 cases in la Reunion's outbreak. These clinical observations have been corroborated by experimental infection in several mouse models, leading to CNS pathologies. We further describe in this review the capacity of CHIKV to infect neurons and glial cells, delineate the fundamental innate (intrinsic) immune defence mechanisms to protect from infection and argue about the possible mechanisms involved in the encephalopathy. (c) 2010 Elsevier Ltd. All rights reserved.

  20. Chest radiographic appearances in adult inpatients admitted with swine flu infection: local experience in Melbourne

    International Nuclear Information System (INIS)

    Pirakalathanan, Janu; Lau, Kenneth K.; Joosten, Simon A.

    2013-01-01

    The influenza A virus (H1N1) pandemic began in Mexico in March 2009. As of July 2009, there were 5298 reported cases in Australia including 10 deaths. The aim of this review is to demonstrate the local chest radiographic findings in adult inpatients with proven H1N1, to assess the radiological disease progression and resolution, and to evaluate whether the severity of chest X-rays findings had a bearing on the length of admission and need for intensive care admission. Eleven H1N1 patients (5 males and 6 females, mean age of 36), presenting with cough (64%), fever (55%) and shortness of breath (55%), were admitted to our hospital between 13 August and 1 November 2010. Details of radiographic features, risk factors, clinical course including length of stay, doubling time of consolidation and time for 50% resolution of consolidation were recorded and analysed. Seventy-three per cent of our patients presented with bilateral mid and/or lower zone alveolar consolidation. One patient with underlying cystic fibrosis had only bilateral upper zone consolidation. No pleural effusion, lymphadenopathy or cardiomegaly was noted on any of the plain chest radiographs. The mean doubling time of consolidation was 1.5 days. The mean time for 50% resolution of consolidation after antiviral treatment was 10.5 days. The average length of stay in hospital was 22 days. Ninety-one per cent of our patients required intensive-care unit admission with 50% of those requiring intubation. Rapid progression of bilateral mid and lower zone air-space opacities in relatively young unwell patients, with lack of pleural effusion, pericardial effusion or lymphadenopathy on plain radiographs, should raise the clinical suspicion of H1N1 infection. Patients requiring hospital admission usually show slow clinical and radiological improvement, and require prolonged hospital stays.

  1. Effects of mutations in the VP2/VP4 cleavage site of Swine vesicular disease virus on RNA encapsidation and viral infectivity

    NARCIS (Netherlands)

    Rebel, J.M.J.; Leendertse, C.H.; Dekker, A.; Moormann, R.J.M.

    2003-01-01

    We studied VP0 cleavage of Swine vesicular disease virus (SVDV), a member of the Picornaviridae using a full-length cDNA copy of the Dutch SVDV isolate. The influences of mutations, introduced at the cleavage site of SVDV, on VP0 cleavage, RNA encapsidation and viral infection were studied. Double

  2. Use of automated real-time reverse transcription-polymerase chain reaction (RT-PCR) to monitor experimental swine vesicular disease virus infection in pigs

    DEFF Research Database (Denmark)

    Reid, S.M.; Paton, D.J.; Wilsden, G.

    2004-01-01

    Automated real-time RT-PCR was evaluated as a diagnostic tool for swine vesicular disease virus (SVDV) infection on a range of samples (vesicular epithelium, serum, nasal swabs, faeces) from four inoculated and three in-contact pigs over a period of 28 days. Traditional diagnostic procedures (vir...

  3. Q fever in Greenland

    DEFF Research Database (Denmark)

    Koch, Anders; Svendsen, Claus Bo; Christensen, Jens Jorgen

    2010-01-01

    We report a patient with Q fever endocarditis in a settlement in eastern Greenland (Isortoq, Ammassalik area). Likely animal sources include sled dogs and seals. Q fever may be underdiagnosed in Arctic areas but may also represent an emerging infection.......We report a patient with Q fever endocarditis in a settlement in eastern Greenland (Isortoq, Ammassalik area). Likely animal sources include sled dogs and seals. Q fever may be underdiagnosed in Arctic areas but may also represent an emerging infection....

  4. Swine brucellosis: current perspectives

    Directory of Open Access Journals (Sweden)

    Olsen SC

    2016-12-01

    Full Text Available SC Olsen, FM Tatum Infectious Bacterial Diseases of Livestock Research Unit, National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Ames, IA, USA Abstract: Brucella suis is a significant zoonotic species that is present in domestic livestock and wildlife in many countries worldwide. Transmission from animal reservoirs is the source of human infection as human-to-human transmission is very rare. Although swine brucellosis causes economic losses in domestic livestock, preventing human infection is the primary reason for its emphasis in disease control programs. Although disease prevalence varies worldwide, in areas outside of Europe, swine brucellosis is predominantly caused by B. suis biovars 1 and 3. In Europe, swine are predominantly infected with biovar 2 which is much less pathogenic in humans. In many areas worldwide, feral or wild populations of swine are important reservoir hosts. Like other Brucella spp. in their natural host, B. suis has developed mechanisms to survive in an intracellular environment and evade immune detection. Limitations in sensitivity and specificity of current diagnostics require use at a herd level, rather for individual animals. There is currently no commercial vaccine approved for preventing brucellosis in swine. Although not feasible in all situations, whole-herd depopulation is the most effective regulatory mechanism to control swine brucellosis. Keywords: livestock, transmission, pathogenicity, vaccine, host, infection

  5. Does perioperative systemic infection or fever increase surgical infection risks after internal fixation of femur and tibia fractures in an intensive care polytrauma unit?

    Science.gov (United States)

    Large, Thomas M; Alton, Timothy B; Patton, Daniel J; Beingessner, Daphne

    2013-10-01

    We hypothesized that internal fixation procedures performed on trauma intensive care unit (ICU) patients with systemic infections, some also febrile, would be at increased risk for deep infection. A total of 128 patients (mean age, 37.4 years; mean Injury Severity Score [ISS], 34.7) admitted to the ICU with 179 femur or tibia fractures developed systemic infections. Systemic infections included sepsis, pneumonia, urinary tract infections, abdominal infections, and wound infections remote to the fracture. Of the fractures, 33 open and 146 closed underwent 150 intramedullary and 29 plate fixation procedures. Data were gathered regarding antibiotic use, systemic infection timing in relation to the date of fixation, and whether fever (>38.2°C) was present within 24 hours of fixation. Patients were followed up for a mean of 491 days. Twenty-eight procedures were performed a mean of 4.7 days after the diagnosis of a systemic infection, and 151 were performed a mean of 9.3 days before the diagnosis. Forty-five procedures were performed in patients who were febrile within 24 hours. Of the 179 procedures, 10 (5.6%) developed a deep infection. Four patients' implant infection was potentially hematogenously seeded with the same organism as their systemic infection. Neither the timing of the systemic infection in relation to the fixation procedure nor the presence of fever within 24 hours of fixation, days of preoperative antibiotics, location of the fracture, type of fixation (intramedullary nail vs. plate fixation), or type of systemic infection was significantly associated with the development of an infection. The only significant risk factor for developing an orthopedic infection was an open fracture (p close conjunction to the diagnosis of systemic infection led to a 5.6% infection rate, which compares favorably with historic infection rates for fixation of open or closed tibia and femur fractures. Therapeutic, level IV.

  6. Association DENV1 and DENV2 infection with high serum levels of soluble thrombomodulin and VEGF in patients with dengue fever and dengue hemorrhagic fever.

    Science.gov (United States)

    Del Moral-Hernández, Oscar; Martínez-Hernández, Norma E; Mosso-Pani, Manuel A; Hernández-Sotelo, Daniel; Illades-Aguiar, Berenice; Flores-Alfaro, Eugenia; Antonio-Vejar, Verónica; Leyva-Vázquez, Marco Antonio

    2014-01-01

    INFECTION BY DENGUE VIRUS (DENV) CAN BE ASYMPTOMATIC OR MANIFEST IN TWO CLINICALLY DIFFERENTIATED FORMS: dengue fever (DF) and denguehemorrhagic fever (DHF). The principal pathophysiological characteristic of DHF is the increase in vascular permeability and the loss of plasma caused by the malfunction of the vascular endothelium that induces the release of chemical mediators. However, so far there is nothing that allows for the identification the patients that are at risk of developing the more severe form of the illness. The objective of this study was to investigate the relationship between the serum levels of soluble thrombomodulin (sTM) and VEGF with the severity of dengue and the viral serotype. 231 serum samples were analyzed, 70 DF, 80 DHF and 81 control group, all were residents of Guerrero state in Mexico. The infection by dengue virus as well and the levels of sTM and VEGF were determined using the ELISA sandwich, while the serotype was determined by real time RT-PCR. Our results show that the concentrations of sTM correlate with the degree of severity of the disease given that they are significantly higher (p<0.001) in the DHF group (median = 10.2 ng/mL) than in the DF group (median = 7.2 ng/mL), and these in turn higher than those of the control group (median = 3.3 ng/mL). The concentration of sTM was significantly higher (p=0.0002) in the patients infected with DENV2. For the VEGF, the highest levels were found in DF (median = 291.3 pg/mL) and did not correlate with the severity of the disease. In conclusion, our results indicate that sTM is a good marker for the severity of the infection by DENV, better than VEGF, and with higher sensibility and specificity.

  7. Acute phase protein response during subclinical infection of pigs with H1N1 swine influenza virus.

    Science.gov (United States)

    Pomorska-Mól, Małgorzata; Markowska-Daniel, Iwona; Pejsak, Zygmunt

    2012-10-12

    In the present study acute phase proteins (APPs) responses in pigs after subclinical infection with H1N1 swine influenza virus (SwH1N1) were evaluated. Fourteen 5 weeks old, seronegative piglets, both sexes were used. Ten of them were infected intranasally with SwH1N1. C-reactive protein (CRP), haptoglobin (Hp), serum amyloid A (SAA) and pig major acute phase protein (Pig-MAP) concentrations in serum were measured using commercial ELISAs. No significant clinical signs were observed in any of the infected pigs, however, all infected animals developed specific antibodies against SwH1N1 and viral shedding was observed from 2 to 5 dpi. Only concentrations of Hp and SAA were significantly induced after infection, with mean maximum levels from days 1 to 2 post infection (dpi). The concentrations of CRP and Pig-MAP remained generally unchanged, however in half of infected pigs the concentration of CRP tended to increase at 1 dpi (but without statistical significance). The results of our study confirmed that monitoring of APPs may be useful for detection of subclinically infected pigs. The use of SAA or Hp and Pig-MAP may be a valuable in combination [i.e. Hp (increased concentration) and Pig-MAP (unchanged concentration)] to detect subclinically SIV infected pigs, or to identify pigs actually producing a large amount of virus. Additional studies need to be done in order to confirm these findings. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. PCA-MLP SVM distinction of salivary Raman spectra of dengue fever infection.

    Science.gov (United States)

    Radzol, A R M; Lee, Khuan Y; Mansor, W; Wong, P S; Looi, I

    2017-07-01

    Dengue fever (DF) is a disease of major concern caused by flavivirus infection. Delayed diagnosis leads to severe stages, which could be deadly. Of recent, non-structural protein (NS1) has been acknowledged as a biomarker, alternative to immunoglobulins for early detection of dengue in blood. Further, non-invasive detection of NS1 in saliva makes the approach more appealing. However, since its concentration in saliva is less than blood, a sensitive and specific technique, Surface Enhanced Raman Spectroscopy (SERS), is employed. Our work here intends to define an optimal PCA-SVM (Principal Component Analysis-Support Vector Machine) with Multilayer Layer Perceptron (MLP) kernel model to distinct between positive and negative NS1 infected samples from salivary SERS spectra, which, to the best of our knowledge, has never been explored. Salivary samples of DF positive and negative subjects were collected, pre-processed and analyzed. PCA and SVM classifier were then used to differentiate the SERS analyzed spectra. Since performance of the model depends on the PCA criterion and MLP parameters, both are examined in tandem. Its performance is also compared to our previous works on simulated NS1 salivary samples. It is found that the best PCA-SVM (MLP) model can be defined by 95 PCs from CPV criterion with P1 and P2 values of 0.01 and -0.2 respectively. A classification performance of [76.88%, 85.92%, 67.83%] is achieved.

  9. The role of signal transducer and activator of transcription 3 in Rift Valley fever virus infection

    Energy Technology Data Exchange (ETDEWEB)

    Pinkham, Chelsea; An, Soyeon; Lundberg, Lindsay; Bansal, Neha; Benedict, Ashwini; Narayanan, Aarthi; Kehn-Hall, Kylene, E-mail: kkehnhal@gmu.edu

    2016-09-15

    Rift Valley fever (RVF) is a zoonotic disease that can cause severe illness in humans and livestock, triggering spontaneous abortion in almost 100% of pregnant ruminants. In this study, we demonstrate that signal transducer and activator of transcription 3 (STAT3) is phosphorylated on its conserved tyrosine residue (Y705) following RVFV infection. This phosphorylation was dependent on a major virulence factor, the viral nonstructural protein NSs. Loss of STAT3 had little effect on viral replication, but rather resulted in cells being more susceptible to RVFV-induced cell death. Phosphorylated STAT3 translocated to the nucleus, coinciding with inhibition of fos, jun, and nr4a2 gene expression, and the presence of STAT3 and NSs at the nr4a2 promoter. NSs was found predominantly in the cytoplasm of STAT3 null cells, indicating that STAT3 influences NSs nuclear localization. Collectively, these data demonstrate that STAT3 functions in a pro-survival capacity through modulation of NSs localization. - Highlights: • STAT3 is phosphorylated on tyrosine residue 705 following RVFV infection. • Phosphorylation of STAT3 was dependent on the viral protein NSs. • STAT3 -/- MEFs were more susceptible to RVFV-induced cell death. • Loss of STAT3 led to an increase in pro-apoptotic gene expression. • STAT3 functions in a pro-survival capacity by modulation of NSs localization.

  10. Risk factors associated with human Rift Valley fever infection: systematic review and meta-analysis.

    Science.gov (United States)

    Nicholas, Dennis E; Jacobsen, Kathryn H; Waters, Nigel M

    2014-12-01

    To identify risk factors for human Rift Valley fever virus (RVFV) infection. A systematic review identified 17 articles reporting on 16 studies examining risk factors for RVFV. Pooled odds ratios (pOR) were calculated for exposures examined in four or more studies. Being male [pOR = 1.4 (1.0, 1.8)], contact with aborted animal tissue [pOR = 3.4 (1.6, 7.3)], birthing an animal [pOR = 3.2 (2.4, 4.2)], skinning an animal [pOR = 2.5 (1.9, 3.2)], slaughtering an animal [pOR = 2.4 (1.4, 4.1)] and drinking raw milk [pOR = 1.8 (1.2, 2.6)] were significantly associated with RVF infection after meta-analysis. Other potential risk factors include sheltering animals in the home and milking an animal, which may both involve contact with animal body fluids. Based on the identified risk factors, use of personal protective equipment and disinfectants by animal handlers may help reduce RVFV transmission during outbreaks. Milk pasteurisation and other possible preventive methods require further investigation. © 2014 John Wiley & Sons Ltd.

  11. Florfenicol feed supplemented decrease the clinical effects of Mycoplasma hyopneumoniae experimental infection in swine in México.

    Science.gov (United States)

    Ciprián, A; Palacios, J M; Quintanar, D; Batista, L; Colmenares, G; Cruz, T; Romero, A; Schnitzlein, W; Mendoza, S

    2012-04-01

    The therapeutic value of Florfenicol feed supplemented was evaluated in conventional pigs to eliminate consequences of chronic infection of Mycoplasma hyopneumoniae. The experimental animals were pigs with an average of 16 kg, after intratracheally inoculation with M. hyopneumoniae they were divided in two experimental groups: (a) the non-medicated; and (b) the feed supplemented group (20 g Florfenicol/ton of feed) during the ensuing 35 days. The average daily weight gain of the Florfenicol-treated pigs (0.33±0.14 kg/day) was significantly higher than that of the non-treated ones (0.21±0.10 kg/day). In medicated animals was still impaired relative to that of the uninfected ones control group (0.39±0.02 kg/day). The average percentage of pneumonic gross lesions extensions' of the pigs groups was: 13.99% for M. hyopneumoniae infected non-medicated group; 1.79% M. hyopneumoniae infected, Florfenicol-treated group and, 0.56% of the uninfected control group. M. hyopneumoniae; colonization was detected at these levels in 7 and 9 members of the respective infected groups. The extent of the pneumonic lesions and M. hyopneumoniae generally was greater in the non-medicated pigs. Therefore, oral administration of Florfenicol via feed ingestion seemed to be somewhat effective in ameliorating the clinical effects of M. hyopneumoniae infection of swine. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Persistent Coxiella burnetii infection in mice overexpressing IL-10: an efficient model for chronic Q fever pathogenesis.

    Directory of Open Access Journals (Sweden)

    Soraya Meghari

    2008-02-01

    Full Text Available Interleukin (IL-10 increases host susceptibility to microorganisms and is involved in intracellular persistence of bacterial pathogens. IL-10 is associated with chronic Q fever, an infectious disease due to the intracellular bacterium Coxiella burnetii. Nevertheless, accurate animal models of chronic C. burnetii infection are lacking. Transgenic mice constitutively expressing IL-10 in macrophages were infected with C. burnetti by intraperitoneal and intratracheal routes and infection was analyzed through real-time PCR and antibody production. Transgenic mice exhibited sustained tissue infection and strong antibody response in contrast to wild-type mice; thus, bacterial persistence was IL-10-dependent as in chronic Q fever. The number of granulomas was low in spleen and liver of transgenic mice infected through the intraperitoneal route, as in patients with chronic Q fever. Macrophages from transgenic mice were unable to kill C. burnetii. C. burnetii-stimulated macrophages were characterized by non-microbicidal transcriptional program consisting of increased expression of arginase-1, mannose receptor, and Ym1/2, in contrast to wild-type macrophages in which expression of inducible NO synthase and inflammatory cytokines was increased. In vivo results emphasized macrophage data. In spleen and liver of transgenic mice infected with C. burnetii by the intraperitoneal route, the expression of arginase-1 was increased while microbicidal pathway consisting of IL-12p40, IL-23p19, and inducible NO synthase was depressed. The overexpression of IL-10 in macrophages prevents anti-infectious competence of host, including the ability to mount granulomatous response and microbicidal pathway in tissues. To our knowledge, this is the first efficient model for chronic Q fever pathogenesis.

  13. Meconium-Stained Amniotic Fluid as an Independent Risk Factor for Fever and Postpartum Infection in Term Pregnancy

    Directory of Open Access Journals (Sweden)

    M Valadan

    2008-06-01

    Full Text Available Background: The aim of this study was to statistically evaluate the hypothesis that the presence of meconium-stained amniotic fluid is associated with postpartum maternal infection.Methods: This prospective cohort study included 573 term pregnant women in labor, with no other medical problems, that underwent cesarean section for pregnancy termination. Women with prolonged active-phase labor, prolonged rupture of membranes, complicated cesarean section and pre-operative infections were excluded from this study.The subjects were divided into two groups: 280 women with meconium-stained amniotic fluid (M group, and 293 women with clear amniotic fluid (C group. A comparison was done regarding postpartum fever, endometritis and wound infection between the two groups. Students t-test and chi square test were used for data analysis, along with linear regression, with p<0.05 indicating significance.Results: Among the 573 women, a total of 82 women (14% had fever after cesarean; 42 women from the M group, and 40 women from the C group (p= 0.3. Among the 82 women who had fever, 33 women had continuous fever, 6.5% in group M and 2.7% in group C (p<0.05, RR: 1.98, 95% CI 1.3-3.1. Among the 573 women, 4% developed endometritis 5% in group M and 2% in group C (p<0.05, RR: 2.3, 95%, CI 1.3-3.4. Similarly, among the 573 women, a total of 5 women (1% developed wound infection, 1.7% in group M and 0.68% in group C (p=0.7.Conclusion: Meconium-stained amniotic fluid is associated with increased postpartum infection independent of other risk factors for infection.

  14. Chest Radiographic Findings of Novel Swine-Origin Influenza A (H1N1) Virus Infection in Children

    Energy Technology Data Exchange (ETDEWEB)

    Bae, So Young; Hong, Eun Sook; Paik, Sang Hyun; Park, Seong Jin; Cha, Jang Gyu; Lee, Hae Kyung [Dept. of Radiology, Soonchunhyang University Bucheon Hospital, Bucheon (Korea, Republic of); Jang, Yun Woo [Dept. of Radiology, Soonchunhyang University Hospital, Seoul (Korea, Republic of)

    2011-06-15

    To analyze chest radiographic findings in children infected with laboratory confirmed novel swine-origin influenza A (H1N1) virus. Three hundred seventy-two out of 2,014 children with laboratory confirmed H1N1 infection and who also underwent a chest radiograph from September to November 2009 were enrolled in this study. Patients were divided into in-patients, out-patients, and patients with co-infections and further subdivided into with underlying disease and without underlying disease as well as age (<2 years old, 2-5 years, 5-10 years, 10-18 years old). The initial radiographs were evaluated for radiographic findings and the anatomic distribution of abnormalities. The initial radiographs were abnormal in 154 (41.39%) patients. The predominant radiographic findings were peribronchial wall opacity found in 85 (22.84%) patients and hyperinflation observed in 69 (18.54%) patients. Further, 75 (71.42%) patients exhibited central predominance and the right lower lung zone was also commonly involved. There were statistically significant differences in the radiological findings between in-patient and out-patient groups. However, there were no significant differences in the radiographic findings between in-patients and the co-infection group with respect the presence of underlying disease and age. Initial radiographs of children with laboratory confirmed H1N1 virus were abnormal in 41.39% of cases. The common radiographic findings included peribronchial opacities, hyperinflation, lower lung zonal distribution, and central predominance

  15. Chest Radiographic Findings of Novel Swine-Origin Influenza A (H1N1) Virus Infection in Children

    International Nuclear Information System (INIS)

    Bae, So Young; Hong, Eun Sook; Paik, Sang Hyun; Park, Seong Jin; Cha, Jang Gyu; Lee, Hae Kyung; Jang, Yun Woo

    2011-01-01

    To analyze chest radiographic findings in children infected with laboratory confirmed novel swine-origin influenza A (H1N1) virus. Three hundred seventy-two out of 2,014 children with laboratory confirmed H1N1 infection and who also underwent a chest radiograph from September to November 2009 were enrolled in this study. Patients were divided into in-patients, out-patients, and patients with co-infections and further subdivided into with underlying disease and without underlying disease as well as age (<2 years old, 2-5 years, 5-10 years, 10-18 years old). The initial radiographs were evaluated for radiographic findings and the anatomic distribution of abnormalities. The initial radiographs were abnormal in 154 (41.39%) patients. The predominant radiographic findings were peribronchial wall opacity found in 85 (22.84%) patients and hyperinflation observed in 69 (18.54%) patients. Further, 75 (71.42%) patients exhibited central predominance and the right lower lung zone was also commonly involved. There were statistically significant differences in the radiological findings between in-patient and out-patient groups. However, there were no significant differences in the radiographic findings between in-patients and the co-infection group with respect the presence of underlying disease and age. Initial radiographs of children with laboratory confirmed H1N1 virus were abnormal in 41.39% of cases. The common radiographic findings included peribronchial opacities, hyperinflation, lower lung zonal distribution, and central predominance

  16. Longitudinal study of Staphylococcus aureus colonization and infection in a cohort of swine veterinarians in the United States

    Directory of Open Access Journals (Sweden)

    Jisun Sun

    2017-10-01

    Full Text Available Abstract Background People working with pigs are at elevated risk of harboring methicillin resistant S. aureus (MRSA in their nose, which is attributable to occupational exposure to animals harboring livestock adapted S. aureus. To obtain insight into the biological nature of occupationally related nasal culture positivity, we conducted a longitudinal study of 66 swine veterinarians in the USA. Methods The study cohort resided in 15 US states and worked predominantly with swine. Monthly for 18 months, participants self-collected nasal swabs and completed a survey to report recent exposure to pigs and other animals; the occurrence of work related injuries; and any relevant health events such as skin and soft tissue infections or confirmed staphylococcal infections. Nasal swabs were cultured using selective methods to determine the presence of MRSA and methicillin susceptible S. aureus (MSSA, and isolates were characterized by spa typing and MLST. Results Prevalences of S. aureus (64%, monthly range from 58 to 82% and MRSA (9.5%; monthly range from 6 to15% were higher than reported for the US population (30% and 1.5% respectively. Predominant spa types were t034 (ST398, 37%, t002 (ST5, 17% and t337 (ST9/ST398 13%, a distribution similar to that found in a concurrent study in pigs in the USA. Veterinarians were classified into three groups: Persistent carriers (PC, 52%, Intermittent carriers (IC, 47% and Non-carriers (NC, 1%. Persistent carriage of a single spa type was observed in 14 (21% of participants, and paired (first and last isolates from PC subjects had minor genetic differences. Swabs from PC veterinarians carried higher numbers of S. aureus. Among IC veterinarians, culture positivity was significantly associated with recent contact with pigs. Conclusions Exposure to pigs did not lead to prolonged colonization in most subjects, and the higher numbers of S. aureus in PC subjects suggests that unknown host factors may determine the

  17. Longitudinal study of Staphylococcus aureus colonization and infection in a cohort of swine veterinarians in the United States.

    Science.gov (United States)

    Sun, Jisun; Yang, My; Sreevatsan, Srinand; Bender, Jeffrey B; Singer, Randall S; Knutson, Todd P; Marthaler, Douglas G; Davies, Peter R

    2017-10-19

    People working with pigs are at elevated risk of harboring methicillin resistant S. aureus (MRSA) in their nose, which is attributable to occupational exposure to animals harboring livestock adapted S. aureus. To obtain insight into the biological nature of occupationally related nasal culture positivity, we conducted a longitudinal study of 66 swine veterinarians in the USA. The study cohort resided in 15 US states and worked predominantly with swine. Monthly for 18 months, participants self-collected nasal swabs and completed a survey to report recent exposure to pigs and other animals; the occurrence of work related injuries; and any relevant health events such as skin and soft tissue infections or confirmed staphylococcal infections. Nasal swabs were cultured using selective methods to determine the presence of MRSA and methicillin susceptible S. aureus (MSSA), and isolates were characterized by spa typing and MLST. Prevalences of S. aureus (64%, monthly range from 58 to 82%) and MRSA (9.5%; monthly range from 6 to15%) were higher than reported for the US population (30% and 1.5% respectively). Predominant spa types were t034 (ST398, 37%), t002 (ST5, 17%) and t337 (ST9/ST398 13%), a distribution similar to that found in a concurrent study in pigs in the USA. Veterinarians were classified into three groups: Persistent carriers (PC, 52%), Intermittent carriers (IC, 47%) and Non-carriers (NC, 1%). Persistent carriage of a single spa type was observed in 14 (21%) of participants, and paired (first and last) isolates from PC subjects had minor genetic differences. Swabs from PC veterinarians carried higher numbers of S. aureus. Among IC veterinarians, culture positivity was significantly associated with recent contact with pigs. Exposure to pigs did not lead to prolonged colonization in most subjects, and the higher numbers of S. aureus in PC subjects suggests that unknown host factors may determine the likelihood of prolonged colonization by S. aureus of livestock

  18. Cross-Reactivity of Rapid Salmonella Typhi IgM Immunoassay in Dengue Fever Without Co-Existing Infection.

    Science.gov (United States)

    Bhatti, Adnan Bashir; Ali, Farhan; Satti, Siddique Akbar

    2015-12-04

    Dengue fever is endemic in developing nations worldwide with as many as 500,000 annual cases of dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). A prompt and accurate diagnosis early in the disease course is essential for prompt identification and treatment of severe complications of the dengue virus infection (DVI). We identified cross-reactivity of a rapid IgM test for typhoid fever in patients with febrile illnesses that were determined to be due to dengue virus. All patients with documented DVI during a recent epidemic in Pakistan also underwent diagnostic testing for Salmonella enterica serovar Typhi. The diagnosis of DVI was made based on clinical findings and the positive results for dengue non-structural protein 1 antigen (NS1Ag) and/or dengue IgM antibody (anti-D IgM) during the acute phase of febrile illness. Patients with positive test results for Salmonella typhi (S. Typhi) IgM also had their blood cultures done. In the group of 322 patients with clinical and serological evidence of DVI, 107 also tested positive for S. Typhi IgM. Blood cultures were negative for S. Typhi bacteria in all patients. Principal disease features included fever, headache, myalgia, retro-orbital pain, and a rash accompanied by thrombocytopenia and leukopenia. Comparisons of clinical and routine laboratory findings between the S. Typhi-positive and negative groups showed no significant differences. Patients testing positive for both NS1Ag and anti-D IgM were significantly more likely to test positive for S. Typhi IgM, even in the absence of typhoid fever. No routine antibiotics were used and all patients survived. One-third of a large group of patients with primary DVI also demonstrated false positive results for typhoid fever. Cross-reactivity of a rapid immunoassay for typhoid fever has not been previously reported in DVI or any other flavivirus infections. Until these findings can be further evaluated, clinicians should be cautious in

  19. Experimental infection of one-day-old chicks with Salmonella Serotypes Previously isolated from poultry facilities, wild birds, and swine

    Directory of Open Access Journals (Sweden)

    E de Sousa

    2013-12-01

    Full Text Available In order to maintain the high production and export rates achieved by the Brazilian poultry industry, it is necessary to prevent and control certain disease agents, such as Salmonella spp. Using bacterial cultures, the aim of the present study was to investigate the prevalence of Salmonella spp. in specimens collected from broiler facilities. Local wild birds were also sampled, as well as the feces of swine housed on the poultry farm. After sample collection, the isolated serotypes were subsequently inoculated into broiler chicks to determine their effects. Positive samples were collected from the following locations in the poultry facilities: poultry litter (S. serotype 4,5,12:R:-; S. Heidelberg; S. Infantis, broiler feces (S. Heidelberg; S. serotype 6,7:R:-; S. serotype 4,5,12:R:-; S. Tennessee, water (S. Glostrup; S. serotype 6,8:d:-;, and lesser mealworms (Alphitobius diaperinus found in the litter (S. Tennessee. Among the 36 wild birds captured, S. Heidelberg was isolated from one bird's organs and intestinal contents (Colaptes campestris, and S. Enteritidis was isolated from another bird's intestinal contents (Zenaida auriculata. Salmonella Panama and Salmonella Typhimurium were isolated from swine feces. One-day-old chicks (150 were divided into 10 groups of 15 animals each. Each group was orally inoculated with a previously isolated serotype of Salmonella. Soft stools were observed on the cage floor and around the birds' cloaca between 3 and 12 days post-infection (dpi. The different serotypes of Salmonella used to inoculate the chicks were re-isolated from the spleen, liver, and cecal content samples of the infected birds on 15 and 21 dpi.

  20. Potential application of silver nanoparticles to control the infectivity of Rift Valley fever virus in vitro and in vivo.

    Science.gov (United States)

    Borrego, Belén; Lorenzo, Gema; Mota-Morales, Josué D; Almanza-Reyes, Horacio; Mateos, Francisco; López-Gil, Elena; de la Losa, Nuria; Burmistrov, Vasily A; Pestryakov, Alexey N; Brun, Alejandro; Bogdanchikova, Nina

    2016-07-01

    In this work we have tested the potential antiviral activity of silver nanoparticles formulated as Argovit™ against Rift Valley fever virus (RVFV). The antiviral activity of Argovit was tested on Vero cell cultures and in type-I interferon receptor deficient mice (IFNAR (-/-) mice) by two different approaches: (i) different dilutions of Argovit were added to previously infected cells or administrated to animals infected with a lethal dose of virus; (ii) virus was pre-incubated with different dilutions of Argovit before inoculation in mice or cells. Though the ability of silver nanoparticles to control an ongoing RVFV infection in the conditions tested was limited, the incubation of virus with Argovit before the infection led to a reduction of the infectivity titers both in vitro and in vivo. These results reveal the potential application of silver nanoparticles to control the infectivity of RVFV, which is an important zoonotic pathogen. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Serological characterization of dengue virus infections observed among dengue hemorrhagic fever/dengue shock syndrome cases in upper Myanmar.

    Science.gov (United States)

    Ngwe Tun, Mya Myat; Thant, Kyaw Zin; Inoue, Shingo; Kurosawa, Yae; Lwin, Yee Yee; Lin, Sanda; Aye, Kay Thi; Thet Khin, Pe; Myint, Tin; Htwe, Khin; Mapua, Cynthia A; Natividad, Filipinas F; Hirayama, Kenji; Morita, Kouichi

    2013-07-01

    In Myanmar, dengue fever (DF)/dengue hemorrhagic fever (DHF) is one of the leading causes of morbidity and mortality among children. From Pyinmana Hospital in 2004 and Mandalay Children Hospital in 2006, 160 patients diagnosed clinically to have DHF/dengue shock syndrome (DSS) were examined for immunoglobulin M (IgM) and IgG levels. A focus reduction neutralization test was also used to determine primary or secondary dengue virus (DENV) infection. By using IgM-capture ELISA, 139 cases were confirmed as DENV infections. Of these IgM-positives, 94 samples were collected 7-24 days from the onset of illness, to which 13 (14%) and 81 (86%) were determined to be primary and secondary DENV infections, respectively. The 13 primary DENV infection cases were spread among the various severity groups (DHF grade I-IV and DSS) and represented age groups ranging from <1 year of age to 9 years of age. The patients in these primary infection cases showed a remarkably high IgM with a low IgG titer response compared with the secondary infection cases. No significant differences were observed in IgG titers with clinical severity. The data obtained in this study suggest that primary DENV infection cases exist certainly among DHF/DSS cases in Myanmar, and that additional mechanism(s) aside from the antibody-dependent enhancement mechanism could have influenced the clinical severity in DHF/DSS cases. Copyright © 2013 Wiley Periodicals, Inc.

  2. Serial Metabolome Changes in a Prospective Cohort of Subjects with Influenza Viral Infection and Comparison with Dengue Fever.

    Science.gov (United States)

    Cui, Liang; Fang, Jinling; Ooi, Eng Eong; Lee, Yie Hou

    2017-07-07

    Influenza virus infection (IVI) and dengue virus infection (DVI) are major public health threats. Between IVI and DVI, clinical symptoms can be overlapping yet infection-specific, but host metabolome changes are not well-described. Untargeted metabolomics and targeted oxylipinomic analyses were performed on sera serially collected at three phases of infection from a prospective cohort study of adult subjects with either H3N2 influenza infection or dengue fever. Untargeted metabolomics identified 26 differential metabolites, and major perturbed pathways included purine metabolism, fatty acid biosynthesis and β-oxidation, tryptophan metabolism, phospholipid catabolism, and steroid hormone pathway. Alterations in eight oxylipins were associated with the early symptomatic phase of H3N2 flu infection, were mostly arachidonic acid-derived, and were enriched in the lipoxygenase pathway. There was significant overlap in metabolome profiles in both infections. However, differences specific to IVI and DVI were observed. DVI specifically attenuated metabolites including serotonin, bile acids and biliverdin. Additionally, metabolome changes were more persistent in IVI in which metabolites such as hypoxanthine, inosine, and xanthine of the purine metabolism pathway remained significantly elevated at 21-27 days after fever onset. This study revealed the dynamic metabolome changes in IVI subjects and provided biochemical insights on host physiological similarities and differences between IVI and DVI.

  3. Presence of viral RNA and proteins in exosomes from the cellular clones resistant to Rift Valley Fever Virus infection.

    Directory of Open Access Journals (Sweden)

    Noor eAhsan

    2016-02-01

    Full Text Available Rift Valley Fever Virus (RVFV is a RNA virus that belongs to the genus Phlebovirus, family Bunyaviridae. It infects humans and livestock and causes Rift Valley fever. RVFV is considered an agricultural pathogen by the USDA, as it can cause up to 100% abortion in cattle and extensive death of newborns. In addition, it is designated as Category A pathogen by the CDC and the NIAID. In some human cases of RVFV infection, the virus causes fever, ocular damage, liver damage, hemorrhagic fever, and death. There are currently limited options for vaccine candidates, which include the MP-12 and clone 13 versions of RVFV. Viral infections often deregulate multiple cellular pathways that contribute to replication and host pathology. We have previously shown that latent HIV-1 and HTLV-1 infected cells secrete exosomes that contain short viral RNAs, limited number of genomic RNAs, and viral proteins. These exosomes largely target neighboring cells and activate the NF-кB pathway, leading to cell proliferation and overall better viral replication. In this manuscript, we studied the effects of exosome formation from RVFV infected cells and their function on recipient cells. We initially infected cells, isolated resistant clones, and further purified using dilution cloning. We then characterized these cells as resistant to new RVFV infection, but sensitive to other viral infections, including Venezuelan Equine Encephalitis Virus (VEEV. These clones contained normal markers (i.e. CD63 for exosomes and were able to activate the TLR pathway in recipient reporter cells. Interestingly, the exosome rich preparations, much like their host cell, contained viral RNA (L, M, and S genome. The RNAs were detected using qRT-PCR in both parental and exosomal preparations as well as in CD63 immunoprecipitates. Viral proteins such as N and a modified form of NSs were present in some of these exosomes. Finally, treatment of recipient cells (T- cells and monocytic cells showed

  4. Mouse model for the Rift Valley fever virus MP12 strain infection

    Science.gov (United States)

    Rift Valley fever virus (RVFV), a Category A pathogen and select agent, is the causative agent of Rift Valley fever. To date, no fully licensed vaccine is available in the U.S. for human or animal use and effective antiviral drugs have not been identified. The RVFV MP12 strain is conditionally licen...

  5. Urinary tract infections and post-operative fever in percutaneous nephrolithotomy

    NARCIS (Netherlands)

    Gutierrez, Jorge; Smith, Arthur; Geavlete, Petrisor; Shah, Hemendra; Kural, Ali Riza; de Sio, Marco; Amón Sesmero, José H.; Hoznek, András; de la Rosette, Jean

    2013-01-01

    To review the incidence of UTIs, post-operative fever, and risk factors for post-operative fever in PCNL patients. Between 2007 and 2009, consecutive PCNL patients were enrolled from 96 centers participating in the PCNL Global Study. Only data from patients with pre-operative urine samples and who

  6. In search of hidden Q-fever outbreaks: linking syndromic hospital clusters to infected goat farms.

    NARCIS (Netherlands)

    Wijngaard, C.C. van den; Dijkstra, F.; Pelt, W. van; Asten, L. van; Kretzschmar, M.; Schimmer, B.; Nagelkerke, N.J.D.; Vellema, P.; Donker, G.A.; Koopmans, M.P.G.

    2011-01-01

    Large Q-fever outbreaks were reported in The Netherlands from May 2007 to 2009, with dairy-goat farms as the putative source. Since Q-fever outbreaks at such farms were first reported in 2005, we explored whether there was evidence of human outbreaks before May 2007. Space-time scan statistics were

  7. Seroprevalence of Infections with Dengue, Rift Valley Fever and Chikungunya Viruses in Kenya, 2007.

    Directory of Open Access Journals (Sweden)

    Caroline Ochieng

    Full Text Available Arthropod-borne viruses are a major constituent of emerging infectious diseases worldwide, but limited data are available on the prevalence, distribution, and risk factors for transmission in Kenya and East Africa. In this study, we used 1,091 HIV-negative blood specimens from the 2007 Kenya AIDS Indicator Survey (KAIS 2007 to test for the presence of IgG antibodies to dengue virus (DENV, chikungunya virus (CHIKV and Rift Valley fever virus (RVFV.The KAIS 2007 was a national population-based survey conducted by the Government of Kenya to provide comprehensive information needed to address the HIV/AIDS epidemic. Antibody testing for arboviruses was performed on stored blood specimens from KAIS 2007 through a two-step sandwich IgG ELISA using either commercially available kits or CDC-developed assays. Out of the 1,091 samples tested, 210 (19.2% were positive for IgG antibodies against at least one of the three arboviruses. DENV was the most common of the three viruses tested (12.5% positive, followed by RVFV and CHIKV (4.5% and 0.97%, respectively. For DENV and RVFV, the participant's province of residence was significantly associated (P≤.01 with seropositivity. Seroprevalence of DENV and RVFV increased with age, while there was no correlation between province of residence/age and seropositivity for CHIKV. Females had twelve times higher odds of exposure to CHIK as opposed to DENV and RVFV where both males and females had the same odds of exposure. Lack of education was significantly associated with a higher odds of previous infection with either DENV or RVFV (p <0.01. These data show that a number of people are at risk of arbovirus infections depending on their geographic location in Kenya and transmission of these pathogens is greater than previously appreciated. This poses a public health risk, especially for DENV.

  8. An analysis of the subtypes of dengue fever infections in Barbados 2003–2007 by reverse transcriptase polymerase chain reaction

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    Gittens-St Hilaire M

    2008-12-01

    Full Text Available Abstract Background To perform a retrospective analysis of patients with IgM antibodies to dengue fever infection to determine the serotypes present by molecular techniques. A representative sample (~20%/per year of patients diagnosed with dengue fever infection were selected based on the detection of IgM antibodies in the acute phase serum sample. RNA was extracted from each sample and reverse transcribed. Following this, the amplicons were electrophoresed and serotyped based on band sizes. Results This study consisted of 71 males and 101 females ranging in age from 0 – 50+ yrs giving a total of 172 persons with an average of 34.4 patients per year. Onset averaged 6.9 days ranging from 0–90 days. Common symptoms were as follows: fever (69%, headache (52%, arthralgia (36%, ocular pain (32%, emesis (15% and lumbar pain (15%. All patients investigated with the exception of one, were infected with DENV-3. Conclusion DENV-3 is currently circulating on the island and not DENV-1 or DENV-2 as in previous years. This has implications for the enhancement of clinical, laboratory and environmental surveillance systems.

  9. Swine-origin influenza A viral (H1N1) infection in children. Chest computed tomography findings

    International Nuclear Information System (INIS)

    Im, Soo-Ah; Kim, Hyo-Lim; Yoon, Jong-seo; Kang, Jin-Han; Lee, Joon-Sung; Chun, Ho-Jong

    2011-01-01

    The aim of this study was to review the chest computed tomography (CT) findings in children with swine-origin influenza (H1N1) virus (S-OIV) infection. The radiologists retrospectively reviewed chest CT findings in 12 children with S-OIV infection and recorded the following findings: ground-glass opacities (GGO), consolidation, nodules, reticular opacities, peribronchial cuffing, and air trapping; distribution; affected lobes. The presence of pleural effusions, pneumomediastinum, pulmonary interstitial emphysema (PIE), and lymphadenopathy was also recorded. Chest CT revealed GGO (67%), consolidation (67%), nodules (25%), peribronchial cuffing (42%), and air trapping (33%). The distribution of the lesions was random (75%), peribronchial (17%), or subpleural (8%). The lobes affected were the lower (92%), upper (58%), and middle (17%) lobes. There were associated pleural effusions (42%), PIE (42%), pneumomediastinum (33%), and lymphadenopathy (75%). Among five patients with air-leak complications, three had a history of allergies and three required the intensive care unit. Chest CT findings in children with S-OIV infection were peribronchial thickening and a mixture of airspace consolidation and GGO with random distribution and lower lobe predominance. Pleural effusion, lymphadenopathy, PIE, and pneumomediastinum may be associated findings. (author)

  10. The Haemophilus ducreyi trimeric autotransporter adhesin DsrA protects against an experimental infection in the swine model of chancroid.

    Science.gov (United States)

    Fusco, William G; Choudhary, Neelima R; Routh, Patty A; Ventevogel, Melissa S; Smith, Valerie A; Koch, Gary G; Almond, Glen W; Orndorff, Paul E; Sempowski, Gregory D; Leduc, Isabelle

    2014-06-24

    Adherence of pathogens to cellular targets is required to initiate most infections. Defining strategies that interfere with adhesion is therefore important for the development of preventative measures against infectious diseases. As an adhesin to host extracellular matrix proteins and human keratinocytes, the trimeric autotransporter adhesin DsrA, a proven virulence factor of the Gram-negative bacterium Haemophilus ducreyi, is a potential target for vaccine development. A recombinant form of the N-terminal passenger domain of DsrA from H. ducreyi class I strain 35000HP, termed rNT-DsrAI, was tested as a vaccine immunogen in the experimental swine model of H. ducreyi infection. Viable homologous H. ducreyi was not recovered from any animal receiving four doses of rNT-DsrAI administered with Freund's adjuvant at two-week intervals. Control pigs receiving adjuvant only were all infected. All animals receiving the rNT-DsrAI vaccine developed antibody endpoint titers between 3.5 and 5 logs. All rNT-DsrAI antisera bound the surface of the two H. ducreyi strains used to challenge immunized pigs. Purified anti-rNT-DsrAI IgG partially blocked binding of fibrinogen at the surface of viable H. ducreyi. Overall, immunization with the passenger domain of the trimeric autotransporter adhesin DsrA accelerated clearance of H. ducreyi in experimental lesions, possibly by interfering with fibrinogen binding. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. The Co- Infection of Crime Congo Hemorrhagic Fever and Brucellosis: A Case Report

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    A Saghafipour

    2012-07-01

    Full Text Available

    Background and Objectives: Crimean-Congo Hemorrhagic fever (CCHF is a viral disease transmitted to ruminants or human by the bite of mature tick vectors. It can be transmitted through contact with the infectious blood or viraemic tissues during slaughter and hospital contacts. 80% of the cases are sub clinical and the rest of them are presenting with an acute febrile and occasionally hemorrhagic disease. The mortality rate of the fulminate form of the disease is equal to 20% to 50%. The hemorrhage is usually in the form of hematoma, melena, nose, conjunctiva, uterine or subcutaneous bleeding. CCHF complications are: encephalitis, optic neuropathy, hepatitis, renal failure and myocardial necrosis.

     

    Case Report: In this article, we’ve discussed a CCHF patient who presented with high fever, myalgia, headache, nausea, vomiting, abdominal pain, diffuse cutaneous and gingival hemorrhage during the course of the disease while the patient was hospitalized. Profound jaundice, petechia and global ecchymosis were considerable. Lab data showed at the beginning of hospitalization that the number of liver enzymes was increased up to 8-10 times. The number of placates were lower than 150000 ml. Moreover, during the first three days there was a decrease in the number of white blood cells and PTT was abnormal. (AST was higher than 100 units per litre. The results of serologic examination of IgM- ELISA virus for CCHF on day 5 and IgG-ELISA on day 10–which were carried out in pasture Institute-were reported to be positive. According to the patient’s history and clinical symptoms, he was also suspicious for Brucellosis and the lab data demonstrated that he is also infected with Brucella. (Wright=1.320, 2ME=1.160 (The patient was a 22 year old man, sheep farmer, residing in the GhalehKamkar area of Qom City.

     

  12. Experimental and Natural Infections of Goats with Severe Fever with Thrombocytopenia Syndrome Virus: Evidence for Ticks as Viral Vector.

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    Yongjun Jiao

    Full Text Available Severe fever with thrombocytopenia syndrome virus (SFTSV, the causative agent for the fatal life-threatening infectious disease, severe fever with thrombocytopenia syndrome (SFTS, was first identified in the central and eastern regions of China. Although the viral RNA was detected in free-living and parasitic ticks, the vector for SFTSV remains unsettled.Firstly, an experimental infection study in goats was conducted in a bio-safety level-2 (BSL-2 facility to investigate virus transmission between animals. The results showed that infected animals did not shed virus to the outside through respiratory or digestive tract route, and the control animals did not get infected. Then, a natural infection study was carried out in the SFTSV endemic region. A cohort of naïve goats was used as sentinel animals in the study site. A variety of daily samples including goat sera, ticks and mosquitoes were collected for viral RNA and antibody (from serum only detection, and virus isolation. We detected viral RNA from free-living and parasitic ticks rather than mosquitoes, and from goats after ticks' infestation. We also observed sero-conversion in all members of the animal cohort subsequently. The S segment sequences of the two recovered viral isolates from one infected goat and its parasitic ticks showed a 100% homology at the nucleic acid level.In our natural infection study, close contact between goats does not appear to transmit SFTSV, however, the naïve animals were infected after ticks' infestation and two viral isolates derived from an infected goat and its parasitic ticks shared 100% of sequence identity. These data demonstrate that the etiologic agent for goat cohort's natural infection comes from environmental factors. Of these, ticks, especially the predominant species Haemaphysalis longicornis, probably act as vector for this pathogen. The findings in this study may help local health authorities formulate and focus preventive measures to contain

  13. Experimental and Natural Infections of Goats with Severe Fever with Thrombocytopenia Syndrome Virus: Evidence for Ticks as Viral Vector.

    Science.gov (United States)

    Jiao, Yongjun; Qi, Xian; Liu, Dapeng; Zeng, Xiaoyan; Han, Yewu; Guo, Xiling; Shi, Zhiyang; Wang, Hua; Zhou, Minghao

    2015-01-01

    Severe fever with thrombocytopenia syndrome virus (SFTSV), the causative agent for the fatal life-threatening infectious disease, severe fever with thrombocytopenia syndrome (SFTS), was first identified in the central and eastern regions of China. Although the viral RNA was detected in free-living and parasitic ticks, the vector for SFTSV remains unsettled. Firstly, an experimental infection study in goats was conducted in a bio-safety level-2 (BSL-2) facility to investigate virus transmission between animals. The results showed that infected animals did not shed virus to the outside through respiratory or digestive tract route, and the control animals did not get infected. Then, a natural infection study was carried out in the SFTSV endemic region. A cohort of naïve goats was used as sentinel animals in the study site. A variety of daily samples including goat sera, ticks and mosquitoes were collected for viral RNA and antibody (from serum only) detection, and virus isolation. We detected viral RNA from free-living and parasitic ticks rather than mosquitoes, and from goats after ticks' infestation. We also observed sero-conversion in all members of the animal cohort subsequently. The S segment sequences of the two recovered viral isolates from one infected goat and its parasitic ticks showed a 100% homology at the nucleic acid level. In our natural infection study, close contact between goats does not appear to transmit SFTSV, however, the naïve animals were infected after ticks' infestation and two viral isolates derived from an infected goat and its parasitic ticks shared 100% of sequence identity. These data demonstrate that the etiologic agent for goat cohort's natural infection comes from environmental factors. Of these, ticks, especially the predominant species Haemaphysalis longicornis, probably act as vector for this pathogen. The findings in this study may help local health authorities formulate and focus preventive measures to contain this infection.

  14. Detection of African swine fever virus in the tissues of asymptomatic pigs in smallholder farming systems along the Kenya-Uganda border: implications for transmission in endemic areas and ASF surveillance in East Africa.

    Science.gov (United States)

    Abworo, Edward Okoth; Onzere, Cynthia; Oluoch Amimo, Joshua; Riitho, Victor; Mwangi, Waithaka; Davies, Jocelyn; Blome, Sandra; Peter Bishop, Richard

    2017-07-01

    The persistence of African swine fever virus (ASFV) in endemic areas, with small-scale but regular outbreaks in domestic pigs, is not well understood. ASFV has not been detected using conventional diagnosis in these pigs or adjacent populations of resistant African wild pigs, that could act as potential carriers during the outbreaks. However, such data are crucial for the design of evidence-based control strategies. We conducted cross-sectional (1107 pigs) and longitudinal (100 pigs) monitoring of ASFV prevalence in local pigs in Kenya and Uganda. The horizontal survey revealed no evidence of ASFV in the serum or blood using either conventional or real-time PCR. One pig consistently tested positive using ELISA, but negative using PCR assays on blood. Interestingly, the isotype of the antibodies from this animal were strongly IgA biased relative to control domestic pigs and warthogs, suggesting a role for mucosal immunity. The tissues from this pig were positive by PCR following post-mortem. Internal organ tissues of 44 healthy pigs (28 sentinel pigs and 16 pigs from slaughter slabs) were tested with four different PCR assays; 15.9 % were positive for ASFV suggesting that healthy pigs carrying ASFV exist in the swine population in the study area. P72 and p54 genotyping of ASFV revealed very limited diversity: all were classified in genotype IX at both loci, as were virtually all viruses causing recent ASF outbreaks in the region. Our study suggests that carrier pigs may play a role in ASF disease outbreaks, although the triggers for outbreaks remain unclear and require further investigation. This study significantly increases scientific knowledge of the epidemiology of ASF in the field in Africa, which will contribute to the design of effective surveillance and control strategies.

  15. Local and systemic immune response in pigs during subclinical and clinical swine influenza infection.

    Science.gov (United States)

    Pomorska-Mól, M; Kwit, K; Markowska-Daniel, I; Kowalski, C; Pejsak, Z

    2014-10-01

    Local and systemic immune responses in pigs intranasally (IN) and intratracheally (IT) inoculated with swine influenza virus (SIV) were studied. No clinical signs were observed in IN-inoculated pigs, while IT-inoculated pigs developed typical signs of influenza. Significantly higher titres of specific antibodies and changes of haematological parameters were found only in IT-inoculated pigs. Because positive correlations between viral titre, local cytokine concentration, and lung pathology have been observed, we hypothesise that both viral load and the local secretion of cytokines play a role in the induction of lung lesions. It could be that a higher replication of SIV stimulates immune cells to secrete higher amounts of cytokines. The results of the present study indicate that pathogenesis of SIV is dependent on both, the damage caused to the lung parenchyma directly by virus, and the effects on the cells of the host's immune system. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Prior infection of pigs with a recent human H3N2 influenza virus confers minimal cross-protection against a European swine H3N2 virus.

    Science.gov (United States)

    Qiu, Yu; van der Meulen, Karen; Van Reeth, Kristien

    2013-11-01

    H3N2 influenza viruses circulating in humans and European pigs originate from the pandemic A/Hong Kong/68 virus. Because of slower antigenic drift in swine, the antigenic divergence between swine and human viruses has been increasing. It remains unknown to what extent this results in a reduced cross-protection between recent human and swine H3N2 influenza viruses. We examined whether prior infection of pigs with an old [A/Victoria/3/75 (A/Vic/75)] or a more recent [A/Wisconsin/67/05 (A/Wis/05)] human H3N2 virus protected against a European swine H3N2 virus [sw/Gent/172/08 (sw/Gent/08)]. Genetic and antigenic relationships between sw/Gent/08 and a selection of human H3N2 viruses were also assessed. After challenge with sw/Gent/08, all challenge controls had high virus titers in the entire respiratory tract at 3 days post-challenge and nasal virus excretion for 5-6 days. Prior infection with sw/Gent/08 or A/Vic/75 offered complete virological protection against challenge. Pigs previously inoculated with A/Wis/05 showed similar virus titers in the respiratory tract as challenge controls, but the mean duration of nasal shedding was 1·3 days shorter. Unlike sw/Gent/08- and A/Vic/75-inoculated pigs, A/Wis/05-inoculated pigs lacked cross-reactive neutralizing antibodies against sw/Gent/08 before challenge, but they showed a more rapid antibody response to sw/Gent/08 than challenge controls after challenge. Cross-protection and serological responses correlated with genetic and antigenic differences. Infection immunity to a recent human H3N2 virus confers minimal cross-protection against a European swine H3N2 virus. We discuss our findings with regard to the recent zoonotic infections of humans in the United States with a swine-origin H3N2 variant virus. © 2013 John Wiley & Sons Ltd.

  17. Can we find a possible structural explanation for antibody-dependent enhancement of dengue virus infection resulting in hemorrhagic fever?

    Science.gov (United States)

    Mikita, Cecilia P; Padlan, Eduardo A

    2016-03-01

    Dengue virus infection is one of the most prevalent mosquito-borne illnesses worldwide, affecting as many as 400 million persons annually. Most people experience a self-limited viral illness, but some experience life-threatening disease. Subsequent infection with other dengue virus serotypes increases the risk of development of severe dengue disease with plasma leakage with or without hemorrhage and end organ impairment. Antibody-dependent enhancement of dengue virus infection has been implicated in the development of severe dengue disease, previously referred to as dengue hemorrhagic fever and dengue shock syndrome. We propose a structural explanation for the role of non-neutralizing antibodies in the development of antibody-dependent enhancement of dengue virus infection via complement fixation or binding to Fcγ receptors facilitating entry into target cells. Published by Elsevier Ltd.

  18. A Clinical Study of Hemorrhagic Fever with Renal Syndrome Caused by Seoul Virus Infection

    OpenAIRE

    Park, Seung Chull; Pyo, Heui Jung; Soe, Jae Bung; Lee, Myung Seok; Kim, Young Hoon; Byun, Kwan Soo; Kang, Kyung Ho; Kim, Min Ja; Kim, Jun Suck; Lee, Ho Wang; Lee, Yong Ju; Lee, Pyung Woo; Seong, In Wha; Baek, Luck Ju

    1989-01-01

    The clinical findings of 29 patients with hemorrhagic fever with renal syndrome (HFRS) caused by Seoul virus were evaluated and compared with the previously reported clinical findings of classic Korean hemorrhagic fever (KHF). The diagnoses of these patients were made by hemagglutination inhibition test. The results were as follows: The disease occurred predominantly in males with a high incidence in the third and fourth decades of life. The highest incidence of the disease occurred in Octobe...

  19. Interaction between Mycoplasma hyopneumoniae and Swine Influenza Virus

    Science.gov (United States)

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

    2001-01-01

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

  20. Fever origins in the tropics.

    Science.gov (United States)

    Odio, W T; Mangalaboyi, L J; M'Belepe, M R; Ditu, M S

    1982-01-01

    The causes of fever were attempted to identify in a prospective study on 300 adult in- and outpatients with fever at Kinshasa Teaching Hospital, Zaire. Infection was by far the primary cause of fever (87%). Tuberculosis occurred in 15% of the inpatients. Malaria was the most frequent febrile disease: one fever in two was malaria. Connective tissue diseases and neoplasms were rare.

  1. Classical Swine Fever—An Updated Review

    Science.gov (United States)

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

    2017-01-01

    Classical swine fever (CSF) remains one of the most important transboundary viral diseases of swine worldwide. The causative agent is CSF virus, a small, enveloped RNA virus of the genus Pestivirus. Based on partial sequences, three genotypes can be distinguished that do not, however, directly correlate with virulence. Depending on both virus and host factors, a wide range of clinical syndromes can be observed and thus, laboratory confirmation is mandatory. To this means, both direct and indirect methods are utilized with an increasing degree of commercialization. Both infections in domestic pigs and wild boar are of great relevance; and wild boars are a reservoir host transmitting the virus sporadically also to pig farms. Control strategies for epidemic outbreaks in free countries are mainly based on classical intervention measures; i.e., quarantine and strict culling of affected herds. In these countries, vaccination is only an emergency option. However, live vaccines are used for controlling the disease in endemically infected regions in Asia, Eastern Europe, the Americas, and some African countries. Here, we will provide a concise, updated review on virus properties, clinical signs and pathology, epidemiology, pathogenesis and immune responses, diagnosis and vaccination possibilities. PMID:28430168

  2. Reassortment process after co-infection of pigs with avian H1N1 and swine H3N2 influenza viruses.

    Science.gov (United States)

    Urbaniak, Kinga; Markowska-Daniel, Iwona; Kowalczyk, Andrzej; Kwit, Krzysztof; Pomorska-Mól, Małgorzata; Frącek, Barbara; Pejsak, Zygmunt

    2017-07-08

    The influenza A virus is highly variable, which, to some degree, is caused by the reassortment of viral genetic material. This process plays a major role in the generation of novel influenza virus strains that can emerge in a new host population. Due to the susceptibility of pigs to infections with avian, swine and human influenza viruses, they are considered intermediate hosts for the adaptation of the avian influenza virus to humans. In order to test the reassortment process in pigs, they were co-infected with H3N2 A/swine/Gent/172/2008 (Gent/08) and H1N1 A/duck/Italy/1447/2005 (Italy/05) and co-housed with a group of naïve piglets. The Gent/08 strains dominated over Italy/05, but reassortment occurred. The reassortant strains of the H1N1 subtype (12.5%) with one gene (NP or M) of swine-origin were identified in the nasal discharge of the contact-exposed piglets. These results demonstrate that despite their low efficiency, genotypically and phenotypically different influenza A viruses can undergo genetic exchange during co-infection of pigs.

  3. Development of a Colloidal Gold Kit for the Diagnosis of Severe Fever with Thrombocytopenia Syndrome Virus Infection

    Directory of Open Access Journals (Sweden)

    Xianguo Wang

    2014-01-01

    Full Text Available It is critical to develop a cost-effective detection kit for rapid diagnosis and on-site detection of severe fever with thrombocytopenia syndrome virus (SFTSV infection. Here, an immunochromatographic assay (ICA to detect SFTSV infection is described. The ICA uses gold nanoparticles coated with recombinant SFTSV for the simultaneous detection of IgG and IgM antibodies to SFTSV. The ICA was developed and evaluated by using positive sera samples of SFTSV infection (n=245 collected from the CDC of China. The reference laboratory diagnosis of SFTSV infection was based on the “gold standard”. The results demonstrated that the positive coincidence rate and negative coincidence rate were determined to be 98.4% and 100% for IgM and 96.7% and 98.6% for IgG, respectively. The kit showed good selectivity for detection of SFTSV-specific IgG and IgM with no interference from positive sera samples of Japanese encephalitis virus infection, Dengue virus infection, Hantavirus infection, HIV infection, HBV surface antigen, HCV antibody, Mycobacterium tuberculosis antibody, or RF. Based on these results, the ICS test developed may be a suitable tool for rapid on-site testing for SFTSV infections.

  4. Development of a quantitative NS1-capture enzyme-linked immunosorbent assay for early detection of yellow fever virus infection.

    Science.gov (United States)

    Ricciardi-Jorge, Taissa; Bordignon, Juliano; Koishi, Andrea; Zanluca, Camila; Mosimann, Ana Luiza; Duarte Dos Santos, Claudia Nunes

    2017-11-24

    Yellow fever is an arboviral disease that causes thousands of deaths every year in Africa and the Americas. However, few commercial diagnostic kits are available. Non-structural protein 1 (NS1) is an early marker of several flavivirus infections and is widely used to diagnose dengue virus (DENV) infection. Nonetheless, little is known about the dynamics of Yellow fever virus (YFV) NS1 expression and secretion, to encourage its use in diagnosis. To tackle this issue, we developed a quantitative NS1-capture ELISA specific for YFV using a monoclonal antibody and recombinant NS1 protein. This test was used to quantify NS1 in mosquito and human cell line cultures infected with vaccine and wild YFV strains. Our results showed that NS1 was detectable in the culture supernatants of both cell lines; however, a higher concentration was maintained as cell-associated rather than secreted into the extracellular milieu. A panel of 73 human samples was used to demonstrate the suitability of YFV NS1 as a diagnostic tool, resulting in 80% sensitivity, 100% specificity, a 100% positive predictive value and a 95.5% negative predictive value compared with RT-PCR. Overall, the developed NS1-capture ELISA showed potential as a promising assay for the detection of early YF infection.

  5. Swine Influenza (Swine Flu) in Pigs

    Science.gov (United States)

    ... Avian Swine Variant Pandemic Other Key Facts about Swine Influenza (Swine Flu) in Pigs Language: English (US) Español Recommend on Facebook Tweet ... visit the CDC seasonal flu website . What is Swine Influenza? Swine Influenza (swine flu) is a respiratory ...

  6. Infection and transmission of Rift Valley fever viruses lacking the NSs and/or NSm genes in mosquitoes: potential role for NSm in mosquito infection.

    Directory of Open Access Journals (Sweden)

    Mary B Crabtree

    Full Text Available BACKGROUND: Rift Valley fever virus is an arthropod-borne human and animal pathogen responsible for large outbreaks of acute and febrile illness throughout Africa and the Arabian Peninsula. Reverse genetics technology has been used to develop deletion mutants of the virus that lack the NSs and/or NSm virulence genes and have been shown to be stable, immunogenic and protective against Rift Valley fever virus infection in animals. We assessed the potential for these deletion mutant viruses to infect and be transmitted by Aedes mosquitoes, which are the principal vectors for maintenance of the virus in nature and emergence of virus initiating disease outbreaks, and by Culex mosquitoes which are important amplification vectors. METHODOLOGY AND PRINCIPAL FINDINGS: Aedes aegypti and Culex quinquefasciatus mosquitoes were fed bloodmeals containing the deletion mutant viruses. Two weeks post-exposure mosquitoes were assayed for infection, dissemination, and transmission. In Ae. aegypti, infection and transmission rates of the NSs deletion virus were similar to wild type virus while dissemination rates were significantly reduced. Infection and dissemination rates for the NSm deletion virus were lower compared to wild type. Virus lacking both NSs and NSm failed to infect Ae. aegypti. In Cx. quinquefasciatus, infection rates for viruses lacking NSm or both NSs and NSm were lower than for wild type virus. CONCLUSIONS/SIGNIFICANCE: In both species, deletion of NSm or both NSs and NSm reduced the infection and transmission potential of the virus. Deletion of both NSs and NSm resulted in the highest level of attenuation of virus replication. Deletion of NSm alone was sufficient to nearly abolish infection in Aedes aegypti mosquitoes, indicating an important role for this protein. The double deleted viruses represent an ideal vaccine profile in terms of environmental containment due to lack of ability to efficiently infect and be transmitted by mosquitoes.

  7. Swine Flu: Prevention to Pandemic

    Directory of Open Access Journals (Sweden)

    Preeti Padda

    2015-03-01

    Full Text Available Swine flu, also known as swine influenza, pig influenza, hog flu and pig flu, is a respiratory disease caused by viruses (influenza viruses that infect the respiratory tract of pigs, resulting in nasal secretions, a barking cough, decreased appetite, and listless behaviour. Swine flu produces most of the same symptoms in pigs as human flu produces in people. Mostly people who are closely associated with pigs (for example, pork processors and farmers acquire the infection and similarly pigs get infected occasionally human flu infection. The cross-species infections (swine virus to man; human flu virus to pigs have always been confined to local areas and have not spread across borders in either pigs or humans. Unfortunately, this cross-species situation with influenza viruses has had the potential to change and cause epidemics and pandemics. Most recent pandemic has been reported in 2009,  where "swine flu" strain, first seen in Mexico, was termed as H1N1 as it was mainly infecting people and exhibited two main surface antigens, H1 (hemagglutinin type 1 and N1 (neuraminidase type1. This unique eight RNA strands from novel H1N1 flu have one strand derived from human flu strains, two from avian (bird strains, and five from swine strains. Since then it has been infecting people here and there. 

  8. Genetic Assessment of African Swine Fever Isolates Involved in Outbreaks in the Democratic Republic of Congo between 2005 and 2012 Reveals Co-Circulation of p72 Genotypes I, IX and XIV, Including 19 Variants

    Directory of Open Access Journals (Sweden)

    Leopold K. Mulumba–Mfumu

    2017-02-01

    Full Text Available African swine fever (ASF is a devastating disease of domestic pigs. It is a socioeconomically important disease, initially described from Kenya, but subsequently reported in most Sub-Saharan countries. ASF spread to Europe, South America and the Caribbean through multiple introductions which were initially eradicated—except for Sardinia—followed by re‑introduction into Europe in 2007. In this study of ASF within the Democratic Republic of the Congo, 62 domestic pig samples, collected between 2005–2012, were examined for viral DNA and sequencing at multiple loci: C-terminus of the B646L gene (p72 protein, central hypervariable region (CVR of the B602L gene, and the E183L gene (p54 protein. Phylogenetic analyses identified three circulating genotypes: I (64.5% of samples, IX (32.3%, and XIV (3.2%. This is the first evidence of genotypes IX and XIV within this country. Examination of the CVR revealed high levels of intra-genotypic variation, with 19 identified variants.

  9. Pneumonia in novel swine-origin influenza A (H1N1) virus infection: High-resolution CT findings

    International Nuclear Information System (INIS)

    Li Ping; Su Dongju; Zhang Jifeng; Xia Xudong; Sui Hong; Zhao Donghui

    2011-01-01

    Objective: The purpose of our study was to review the initial high-resolution CT (HRCT) findings in pneumonia patients with presumed/laboratory-confirmed novel swine-origin influenza A (H1N1) virus (S-OIV) infection and detect pneumonia earlier. Materials and methods: High-resolution CT (HRCT) findings of 106 patients with presumed/laboratory-confirmed novel S-OIV (H1N1) infection were reviewed. The 106 patients were divided into two groups according to the serious condition of the diseases. The pattern (consolidation, ground-glass, nodules, and reticulation), distribution, and extent of abnormality on the HRCT were evaluated in both groups. The dates of the onset of symptoms of the patients were recorded. Results: The predominant CT findings in the patients at presentation were unilateral or bilateral multifocal asymmetric ground-glass opacities alone (n = 29, 27.4%), with unilateral or bilateral consolidation (n = 50, 47.2%). The consolidation had peribronchovascular and subpleural predominance. The areas of consolidation were found mainly in the posterior, middle and lower regions of the lungs. Reticular opacities were found in 6 cases of the initial MDCT scan. The extent of disease was greater in group 1 patients requiring advanced mechanical ventilation, with diffuse involvement in 19 patients (63.3%) of group 1 patients, and only 15/76 (19.7%) of group 2 patients (p 2 test). 20 cases (19%) of the 106 patients had small bilateral or unilateral pleural effusions. None had evidence of hilar or mediastinal lymph node enlargement on CT performed at admission or later. Conclusions: The most common radiographic and CT findings in patients with S-OIV infection are unilateral or bilateral ground-glass opacities with or without associated focal or multifocal areas of consolidation. On HRCT, the ground-glass opacities had a predominant peribronchovascular and subpleural distribution. CT plays an important role in the early recognition of severe S-OIV (H1N1).

  10. Detection and Isolation of Swine Influenza A Virus in Spiked Oral Fluid and Samples from Individually Housed, Experimentally Infected Pigs: Potential Role of Porcine Oral Fluid in Active Influenza A Virus Surveillance in Swine.

    Directory of Open Access Journals (Sweden)

    Inge Decorte

    Full Text Available The lack of seasonality of swine influenza A virus (swIAV in combination with the capacity of swine to harbor a large number of co-circulating IAV lineages, resulting in the risk for the emergence of influenza viruses with pandemic potential, stress the importance of swIAV surveillance. To date, active surveillance of swIAV worldwide is barely done because of the short detection period in nasal swab samples. Therefore, more sensitive diagnostic methods to monitor circulating virus strains are requisite.qRT-PCR and virus isolations were performed on oral fluid and nasal swabs collected from individually housed pigs that were infected sequentially with H1N1 and H3N2 swIAV strains. The same methods were also applied to oral fluid samples spiked with H1N1 to study the influence of conservation time and temperature on swIAV infectivity and detectability in porcine oral fluid.All swIAV infected animals were found qRT-PCR positive in both nasal swabs and oral fluid. However, swIAV could be detected for a longer period in oral fluid than in nasal swabs. Despite the high detectability of swIAV in oral fluid, virus isolation from oral fluid collected from infected pigs was rare. These results are supported by laboratory studies showing that the PCR detectability of swIAV remains unaltered during a 24 h incubation period in oral fluid, while swIAV infectivity drops dramatically immediately upon contact with oral fluid (3 log titer reduction and gets lost after 24 h conservation in oral fluid at ambient temperature.Our data indicate that porcine oral fluid has the potential to replace nasal swabs for molecular diagnostic purposes. The difficulty to isolate swIAV from oral fluid could pose a drawback for its use in active surveillance programs.

  11. Detection and Isolation of Swine Influenza A Virus in Spiked Oral Fluid and Samples from Individually Housed, Experimentally Infected Pigs: Potential Role of Porcine Oral Fluid in Active Influenza A Virus Surveillance in Swine

    Science.gov (United States)

    Decorte, Inge; Steensels, Mieke; Lambrecht, Bénédicte

    2015-01-01

    Background The lack of seasonality of swine influenza A virus (swIAV) in combination with the capacity of swine to harbor a large number of co-circulating IAV lineages, resulting in the risk for the emergence of influenza viruses with pandemic potential, stress the importance of swIAV surveillance. To date, active surveillance of swIAV worldwide is barely done because of the short detection period in nasal swab samples. Therefore, more sensitive diagnostic methods to monitor circulating virus strains are requisite. Methods qRT-PCR and virus isolations were performed on oral fluid and nasal swabs collected from individually housed pigs that were infected sequentially with H1N1 and H3N2 swIAV strains. The same methods were also applied to oral fluid samples spiked with H1N1 to study the influence of conservation time and temperature on swIAV infectivity and detectability in porcine oral fluid. Results All swIAV infected animals were found qRT-PCR positive in both nasal swabs and oral fluid. However, swIAV could be detected for a longer period in oral fluid than in nasal swabs. Despite the high detectability of swIAV in oral fluid, virus isolation from oral fluid collected from infected pigs was rare. These results are supported by laboratory studies showing that the PCR detectability of swIAV remains unaltered during a 24 h incubation period in oral fluid, while swIAV infectivity drops dramatically immediately upon contact with oral fluid (3 log titer reduction) and gets lost after 24 h conservation in oral fluid at ambient temperature. Conclusions Our data indicate that porcine oral fluid has the potential to replace nasal swabs for molecular diagnostic purposes. The difficulty to isolate swIAV from oral fluid could pose a drawback for its use in active surveillance programs. PMID:26431039

  12. Influence of Fever and Hospital-Acquired Infection on the Incidence of Delayed Neurological Deficit and Poor Outcome after Aneurysmal Subarachnoid Hemorrhage

    Directory of Open Access Journals (Sweden)

    G. Logan Douds

    2012-01-01

    Full Text Available Although fever and infection have been implicated in the causation of delayed neurological deficits (DND and poor outcome after aneurysmal subarachnoid hemorrhage (SAH, the relationship between these two often related events has not been extensively studied. We reviewed these events through of our retrospective database of patients with SAH. Multivariate logistic regression was used to determine independent predictors of DND and poor outcome. A total of 186 patients were analyzed. DND was noted in 76 patients (45%. Fever was recorded in 102 patients (55%; infection was noted in 87 patients (47%. A patient with one infection was more likely to experience DND compared to a patient with no infections (adjusted OR 3.73, 95% CI 1.62, 8.59. For those with more than two infections the likelihood of DND was even greater (adjusted OR 4.24, 95% CI 1.55, 11.56. Patients with 1-2 days of fever were less likely to have a favorable outcome when compared to their counterparts with no fever (adjusted OR 0.19, 95% CI 0.06, 0.62. This trend worsened as the number of days febrile increased. These data suggest that the presence of infection is associated with DND, but that fever may have a stronger independent association with overall outcome.

  13. Distribution of Soft Ticks and Their Natural Infection with Borrelia in a Focus of Relapsing Fever in Iran

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    Z Aghighi

    2007-11-01

    Full Text Available Tick-borne diseases such as relapsing fever and Crimean-Congo Hemorrhagic Fever (CCHF are of public health impor¬tance in Iran. There are 471 reported cases of relapsing fever in 2003, according to the Ministry of Health of Iran.The num¬ber of cases has been increased in recent years. Its distribution is more or less prevalent in different parts of Iran. The aim of this study was to find out the fauna and natural infection of soft ticks with Borrelia in Qazvin Province, during their sea¬sonal activity. The province covers 15821 km² between 48-45 to 50-50 east of Greenwich Meridian of longitude and 35-37 to 36-45 north latitude of the equator. For this purpose a field study was carried out in the region. A total of 54 villages from 19 districts were selected ran¬domly and ticks were collected from their habitats according to the standard method. A total of 3197 Argasidae ticks were collected from human dwellings, poultry and animal shelters. They belonged to Argas and Or¬nithodoros genera which 36.8% were Argas persicus, 4% A. reflexus, 6.4% O. canestrini, 45.5% O. lahorensis and 7.3% O. tholozani. It should be noted that 12 ticks of O. erraticus were collected from 12 rodents borrows. We found that 8.82 % of O. tholozani ticks were infected with Borrelia persica and half of the O. erraticus were infected with Borrelia microti. All the people who are in¬volved with veterinary activities should be aware of disease transmission by the ticks. In the endemic area of the disease tick control is recommended.

  14. Distribution of Soft Ticks and Their Natural Infection with Borrelia in a Focus of Relapsing Fever in Iran

    Directory of Open Access Journals (Sweden)

    Z Aghighi

    2007-12-01

    Full Text Available Tick-borne diseases such as relapsing fever and Crimean-Congo Hemorrhagic Fever (CCHF are of public health impor¬tance in Iran. There are 471 reported cases of relapsing fever in 2003, according to the Ministry of Health of Iran.The num¬ber of cases has been increased in recent years. Its distribution is more or less prevalent in different parts of Iran. The aim of this study was to find out the fauna and natural infection of soft ticks with Borrelia in Qazvin Province, during their sea¬sonal activity. The province covers 15821 km² between 48-45 to 50-50 east of Greenwich Meridian of longitude and 35-37 to 36-45 north latitude of the equator. For this purpose a field study was carried out in the region. A total of 54 villages from 19 districts were selected ran¬domly and ticks were collected from their habitats according to the standard method. A total of 3197 Argasidae ticks were collected from human dwellings, poultry and animal shelters. They belon