| deletion of the thymidine kinase gene induces complete attenuation of the georgia isolate of african swine fever virus. | 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 deleting virus genes involved in virulence, including the thymidine kinase (tk) gene. tk has been shown to be involved in the virulence of several viruses, including asfv. here we report the constructio ... | 2016 | 26656424 |
| genome sequence of african swine fever virus ba71, the virulent parental strain of the nonpathogenic and tissue-culture adapted ba71v. | the strain ba71v has played a key role in african swine fever virus (asfv) research. it was the first genome sequenced, and remains the only genome completely determined. a large part of the studies on the function of asfv genes, viral transcription, replication, dna repair and morphogenesis, has been performed using this model. this avirulent strain was obtained by adaptation to grow in vero cells of the highly virulent ba71 strain. we report here the analysis of the genome sequence of ba71 in ... | 2015 | 26618713 |
| small-scale pig farmers' behavior, silent release of african swine fever virus and consequences for disease spread. | the expanding distribution of african swine fever (asf) is threatening the pig industry worldwide. most outbreaks occur in backyard and small-scale herds, where poor farmers often attempt to limit the disease's economic consequences by the emergency sale of their pigs. the risk of african swine fever virus (asfv) release via this emergency sale was investigated. simulation modeling was used to study asfv transmission in backyard and small-scale farms as well as the emergency sale of pigs, and th ... | 2015 | 26610850 |
| cholesterol flux is required for endosomal progression of african swine fever virions during the initial establishment of infection. | african swine fever virus (asfv) is a major threat for porcine production that has been slowly spreading in eastern europe since its first appearance in the caucasus in 2007. asfv enters the cell by endocytosis and gains access to the cytosol to start replication from late endosomes and multivesicular bodies. cholesterol associated with low-density lipoproteins entering the cell by endocytosis also follows a trafficking pathway similar to that of asfv. here we show that cholesterol plays an esse ... | 2015 | 26608317 |
| live attenuated african swine fever viruses as ideal tools to dissect the mechanisms involved in viral pathogenesis and immune protection. | african swine fever virus (asfv) is the causal agent of african swine fever, a hemorrhagic and often lethal porcine disease causing enormous economical losses in affected countries. endemic for decades in most of the sub-saharan countries and sardinia, the risk of asfv-endemicity in europe has increased since its last introduction into europe in 2007. live attenuated viruses have been demonstrated to induce very efficient protective immune responses, albeit most of the time protection was circum ... | 2015 | 26589145 |
| first detection of antibodies against african swine fever virus in faeces samples. | african swine fever (asf) is a viral, highly lethal haemorrhagic disease of swine with no available vaccine or effective treatment. introduction of asf into a country triggers immediate restriction measures that cause significant economic losses and threatens spread to neighbouring countries. wild boar populations have been recently assigned an essential role in the spread of african swine fever virus (asfv) to european countries. therefore, effective surveillance and monitoring of wild boar pop ... | 2015 | 26431943 |
| alterations of nuclear architecture and epigenetic signatures during african swine fever virus infection. | viral interactions with host nucleus have been thoroughly studied, clarifying molecular mechanisms and providing new antiviral targets. considering that african swine fever virus (asfv) intranuclear phase of infection is poorly understood, viral interplay with subnuclear domains and chromatin architecture were addressed. nuclear speckles, cajal bodies, and promyelocytic leukaemia nuclear bodies (pml-nbs) were evaluated by immunofluorescence microscopy and western blot. further, efficient pml pro ... | 2015 | 26389938 |
| early intranuclear replication of african swine fever virus genome modifies the landscape of the host cell nucleus. | although african swine fever virus (asfv) replicates in viral cytoplasmic factories, the presence of viral dna within the host cell nucleus has been previously reported to be essential for productive infection. herein, we described, for the first time, the intranuclear distribution patterns of viral dna replication events, preceding those that occur in the cytoplasmic compartment. using brdu pulse-labelling experiments, newly synthesized asfv genomes were exclusively detected inside the host cel ... | 2015 | 26183880 |
| [continuous cell subline a4c2/9k and its application to the african swine fever virus study]. | a new continuous cell subline a4c2/9k highly sensitive to the african swine fever virus (asfv) was prepared. all the tested asfv strains isolated in the russian federation in 2008-2013 proliferated in this cell culture exhibiting hemadsorption and accumulated at a titer of up to 6.5 ig hau50/cm3. the cell culture a4c2/9k can be used for asfv isolation or determination of its infectious activity and serotype identity. the culture versions of the asfv strain stavropol 01/08 at passages 24 and 33 i ... | 2015 | 26182658 |
| survival of african swine fever virus in excretions from pigs experimentally infected with the georgia 2007/1 isolate. | african swine fever virus (asfv) causes a lethal haemorrhagic disease of swine which can be transmitted through direct contact with infected animals and their excretions or indirect contact with contaminated fomites. the shedding of asfv by infected pigs and the stability of asfv in the environment will determine the extent of environmental contamination. the recent outbreaks of asf in europe make it essential to develop disease transmission models in order to design effective control strategies ... | 2017 | 26104842 |
| african swine fever virus assembles a single membrane derived from rupture of the endoplasmic reticulum. | collective evidence argues that two members of the nucleocytoplasmic large dna viruses (ncldvs) acquire their membrane from open membrane intermediates, postulated to be derived from membrane rupture. we now study membrane acquisition of the ncldv african swine fever virus. by electron tomography (et), the virion assembles a single bilayer, derived from open membrane precursors that collect as ribbons in the cytoplasm. biochemically, lumenal endoplasmic reticulum (er) proteins are released into ... | 2015 | 26096327 |
| african swine fever virus georgia 2007 with a deletion of virulence-associated gene 9gl (b119l), when administered at low doses, leads to virus attenuation in swine and induces an effective protection against homologous challenge. | african swine fever virus (asfv) is the etiological agent of an often lethal disease of domestic pigs. disease control strategies have been hampered by the unavailability of vaccines against asfv. since its introduction in the republic of georgia, a highly virulent virus, asfv georgia 2007 (asfv-g), has caused an epizootic that spread rapidly into eastern european countries. currently no vaccines are available or under development to control asfv-g. in the past, genetically modified asfvs harbor ... | 2015 | 26063424 |
| host cell targets for african swine fever virus. | viruses are strict intracellular pathogens that require the cellular environment to complete a successful infection. among them, african swine fever virus (asfv) is an evolutionary ancient dna virus, endemic in africa, which is nowadays causing an emergent disease in europe with a potential high economic impact in the pig industry. it is well known that host-cell components are critical crossroads mapping the virus path for a productive infection, some of them at the endocytic pathway. consideri ... | 2015 | 26057710 |
| [on the situation of african swine fever and the biological characterization of recent virus isolates]. | african swine fever (asf), a disease notifiable to the world organization of animal health (oie), is characterized by severe, unspecific clinical signs and high mortality rates. hosts for asf virus (asfv) are only members of the family suidae and soft ticks of the genus ornithodoros. currently, no vaccine is available and therefore, the control is primarily based on strict sanitary measures. the most important part is the early detection of the disease within affected animal holdings and the fas ... | 2015 | 26054220 |
| experimental pig-to-pig transmission dynamics for african swine fever virus, georgia 2007/1 strain. | african swine fever virus (asfv) continues to cause outbreaks in domestic pigs and wild boar in eastern european countries. to gain insights into its transmission dynamics, we estimated the pig-to-pig basic reproduction number (r 0) for the georgia 2007/1 asfv strain using a stochastic susceptible-exposed-infectious-recovered (seir) model with parameters estimated from transmission experiments. models showed that r 0 is 2·8 [95% confidence interval (ci) 1·3-4·8] within a pen and 1·4 (95% ci 0·6- ... | 2016 | 25989921 |
| phylogeographic analysis of african swine fever virus based on the p72 gene sequence. | african swine fever virus (asfv) outbreak has been considered as an emerging and re-emerging disease for almost a century. diagnostically, simple polymerase chain reaction and sequencing-based molecular detection could be employed for both viral identification and genotyping. this study established a novel phylogenetic analysis and epidemiology comparison based on 205 bp of p72 gene sequences. based on this partial p72 fragment, an updated list of 44 different genotypes from a total of 516 asfv ... | 2015 | 25966230 |
| the assessment of african swine fever virus risk to belgium early 2014, using the quick and semiquantitative pandora screening protocol. | a risk assessment was organized during the early eu asf outbreaks of early 2014 (february-april) and performed in cooperation with 15 belgian and european experts on asfv and its epidemiology in pigs/wild boar. african swine fever (asf) is considered as one of the most dangerous infectious pig diseases, causing many outbreaks. since the end of 2013 - early 2014, several outbreaks within the european union (lithuania, poland, estonia and latvia) were reported to oie, which prompted several risk a ... | 2017 | 25939453 |
| evaluation of the risk factors contributing to the african swine fever occurrence in sardinia, italy. | this study assesses the relation between hypothesized risk factors and african swine fever virus (asfv) distribution in sardinia (italy) after the beginning of the eradication program in 1993, using a bayesian multivariable logistic regression mixed model. results indicate that the probability of asfv occurrence in sardinia was associated to particular socio-cultural, productive and economical factors found in the region, particularly to large number of confined (i.e., closed) farms (most of the ... | 2015 | 25926829 |
| course and transmission characteristics of oral low-dose infection of domestic pigs and european wild boar with a caucasian african swine fever virus isolate. | 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 dom ... | 2015 | 25916610 |
| cd2v interacts with adaptor protein ap-1 during african swine fever infection. | 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 n ... | 2015 | 25915900 |
| faustovirus, an asfarvirus-related new lineage of giant viruses infecting amoebae. | giant viruses are protist-associated viruses belonging to the proposed order megavirales; almost all have been isolated from acanthamoeba spp. their isolation in humans suggests that they are part of the human virome. using a high-throughput strategy to isolate new giant viruses from their original protozoan hosts, we obtained eight isolates of a new giant viral lineage from vermamoeba vermiformis, the most common free-living protist found in human environments. this new lineage was proposed to ... | 2015 | 25878099 |
| impact on antibody responses of b-cell-restricted transgenic expression of a viral gene inhibiting activation of nf-κb and nfat. | in this work, we have assessed the impact in vivo of the evasion gene a238l of african swine fever virus, an inhibitor of both nf-κb- and nfat-mediated transcription. the a238l gene was selectively expressed in mouse b lymphocytes using the promoter and enhancer sequences of the mouse ig μ heavy chain. the igm primary and igg2b secondary serological responses and the number of splenic germinal centres in response to the td antigens dnp-keyhole limpet hemocyanin and sheep red blood cells, respect ... | 2015 | 25864175 |
| analysis of hdac6 and bag3-aggresome pathways in african swine fever viral factory formation. | 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 ... | 2015 | 25856634 |
| tandem repeat insertion in african swine fever virus, russia, 2012. | | 2015 | 25812015 |
| african swine fever virus georgia isolate harboring deletions of mgf360 and mgf505 genes is attenuated in swine and confers protection against challenge with virulent parental virus. | african swine fever virus (asfv) is the etiological agent of a contagious and often lethal disease of domestic pigs that has significant economic consequences for the swine industry. the control of african swine fever (asf) has been hampered by the unavailability of vaccines. experimental vaccines have been developed using genetically modified live attenuated asfvs where viral genes involved in virus virulence were removed from the genome. multigene family 360 (mgf360) and mgf505 represent a gro ... | 2015 | 25810553 |
| experimental infection of domestic pigs with african swine fever virus lithuania 2014 genotype ii field isolate. | an experimental infection was conducted to evaluate horizontal transmission, clinical, virological and humoral response induced in domestic pigs infected with african swine fever (asf) genotype ii virus circulating in 2014 into the european union (eu). ten naive pigs were placed in contact with eight pigs experimentally inoculated with the lithuanian lt14/1490 asf virus (asfv) responsible for the first asf case detected in wild boar in lithuania in january 2014. clinical examination and rectal t ... | 2017 | 25808027 |
| a study of lymphoid organs and serum proinflammatory cytokines in pigs infected with african swine fever virus genotype ii. | 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 sple ... | 2015 | 25797197 |
| 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. | 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 ... | 2016 | 25691347 |
| african swine fever virus infects macrophages, the natural host cells, via clathrin- and cholesterol-dependent endocytosis. | the main cellular target for african swine fever virus (asfv) is the porcine macrophage. however, existing data about the early phases of infection were previously characterized in non-leukocyte cells such as vero cells. here, we report that asfv enters the natural host cell using dynamin-dependent and clathrin-mediated endocytosis. this pathway is strongly ph-dependent during the first steps of infection in porcine macrophages. we investigated the effect of drugs inhibiting several endocytic pa ... | 2015 | 25662020 |
| comparative analysis of the complete genome sequences of kenyan african swine fever virus isolates within p72 genotypes ix and x. | twelve complete african swine fever virus (asfv) genome sequences are currently publicly available and these include only one sequence from east africa. we describe genome sequencing and annotation of a recent pig-derived p72 genotype ix, and a tick-derived genotype x isolate from kenya using the illumina platform and comparison with the kenya 1950 isolate. the three genomes constitute a cluster that was phylogenetically distinct from other asfv genomes, but 98-99 % conserved within the group. v ... | 2015 | 25645905 |
| insulated isothermal reverse transcriptase pcr (iirt-pcr) for rapid and sensitive detection of classical swine fever virus. | classical swine fever (csf) is an oie-listed disease that can have a severe impact on the swine industry. user-friendly, sensitive, rapid diagnostic tests that utilize low-cost field-deployable instruments for csf diagnosis can be useful for disease surveillance and outbreak monitoring. in this study, we describe validation of a new probe-based insulated isothermal reverse transcriptase pcr (iirt-pcr) assay for rapid detection of classical swine fever virus (csfv) on a compact, user-friendly dev ... | 2016 | 25644051 |
| comparative analysis of african swine fever virus genotypes and serogroups. | african swine fever virus (asfv) causes highly lethal hemorrhagic disease among pigs, and asfv's extreme antigenic diversity hinders vaccine development. we show that p72 asfv phylogenetic analysis does not accurately define asfv hemadsorption inhibition assay serogroups. thus, conventional asfv genotyping cannot discriminate between viruses of different virulence or predict efficacy of a specific asfv vaccine. | 2015 | 25625574 |
| african swine fever virus cd2v and c-type lectin gene loci mediate serological specificity. | african swine fever (asf) is an emerging disease threat for the swine industry worldwide. no asf vaccine is available and progress is hindered by lack of knowledge concerning the extent of asf virus (asfv) strain diversity and the viral antigens responsible for protection in the pig. available data from vaccination/challenge experiments in pigs indicate asf protective immunity is haemadsorption inhibition (hai) serotype-specific. a better understanding of asfv hai serological groups and their di ... | 2015 | 25524164 |
| the progressive adaptation of a georgian isolate of african swine fever virus to vero cells leads to a gradual attenuation of virulence in swine corresponding to major modifications of the viral genome. | african swine fever virus (asfv) causes a contagious and often lethal disease of feral and domestic swine. experimental vaccines derived from naturally occurring, genetically modified, or cell culture-adapted asfv have been evaluated, but no commercial vaccine is available to control african swine fever (asf). we report here the genotypic and phenotypic analysis of viruses obtained at different passages during the process of adaptation of a virulent asfv field isolate from the republic of georgi ... | 2015 | 25505073 |
| investigation into the epidemiology of african swine fever virus at the wildlife - domestic interface of the gorongosa national park, central mozambique. | an epidemiological study of african swine fever (asf) was conducted between march 2006 and september 2007 in a rural area adjacent to the gorongosa national park (gnp) located in the central mozambique. domestic pigs and warthogs were sampled to determine the prevalence of antibodies against asf virus and the salivary antigens of ornithodoros spp. ticks, while ticks collected from pig pens were tested for the presence of asfv. in addition, 310 framers were interviewed to gain a better understand ... | 2016 | 25483914 |
| african swine fever virus orf p1192r codes for a functional type ii dna topoisomerase. | topoisomerases modulate the topological state of dna during processes, such as replication and transcription, that cause overwinding and/or underwinding of the dna. african swine fever virus (asfv) is a nucleo-cytoplasmic double-stranded dna virus shown to contain an ofr (p1192r) with homology to type ii topoisomerases. here we observed that pp1192r is highly conserved among asfv isolates but dissimilar from other viral, prokaryotic or eukaryotic type ii topoisomerases. in both asfv/ba71v-infect ... | 2015 | 25463606 |
| alternative sampling strategies for passive classical and african swine fever surveillance in wild boar--extension towards african swine fever virus antibody detection. | | 2014 | 25448452 |
| tree imbalance causes a bias in phylogenetic estimation of evolutionary timescales using heterochronous sequences. | phylogenetic estimation of evolutionary timescales has become routine in biology, forming the basis of a wide range of evolutionary and ecological studies. however, there are various sources of bias that can affect these estimates. we investigated whether tree imbalance, a property that is commonly observed in phylogenetic trees, can lead to reduced accuracy or precision of phylogenetic timescale estimates. we analysed simulated data sets with calibrations at internal nodes and at the tips, taki ... | 2015 | 25431227 |
| african swine fever diagnosis adapted to tropical conditions by the use of dried-blood filter papers. | 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 w ... | 2016 | 25430732 |
| the medical and veterinary role of ornithodoros erraticus complex ticks (acari: ixodida) on the iberian peninsula. | argasid ticks of the ornithodoros erraticus complex are associated with traditional pig-farming practices on the iberian peninsula and are also found elsewhere in north africa, west africa, and western asia. the ticks associated with pig farming on the iberian peninsula are the only biological vectors of african swine fever virus (asfv) known to occur in europe, and their ecology makes them an extremely effective reservoir of both asfv and the borrelia species which cause tick-borne relapsing fe ... | 2014 | 25424252 |
| related strains of african swine fever virus with different virulence: genome comparison and analysis. | two strains of african swine fever virus (asfv), the high-virulence lisboa60 (l60) and the low-virulence nh/p68 (nhv), which have previously been used in effective immunization/protection studies, were sequenced. both were isolated in portugal during the 11-year period after the introduction of asfv to the european continent in 1957. the predicted proteins coded by both strains were compared, and where differences were found these were also compared to other strains of known virulence. this high ... | 2015 | 25406173 |
| in situ hybridization with labeled probes: assessment of african swine fever virus in formalin-fixed paraffin-embedded tissues. | in situ hybridization (ish) has become a very valuable molecular diagnostic tool to detect specific dna or rna sequences in biological samples through the use of complementary dna- or rna-labeled probes. here, we describe an optimized in situ hybridization protocol to detect african swine fever virus (asfv) dna in formalin-fixed, paraffin-embedded tissues using digoxigenin-labeled probes. | 2015 | 25399099 |
| evaluation of hemostaseological status of pigs experimentally infected with african swine fever virus. | african swine fever is a highly contagious hemorrhagic disease of pigs caused by african swine fever virus (asfv). hemorrhages are the most frequently reported lesions in acute and subacute forms of asf. hemorrhagic lesions are accompanied by impaired hemostasis, which includes thrombocytopenia and changes in the coagulation system. in the present study, experimental infection was conducted to elucidate whether a highly virulent asfv genotype ii circulating in the trans-caucasus and eastern euro ... | 2014 | 25239678 |
| expression library immunization can confer protection against lethal challenge with african swine fever virus. | african swine fever is one of the most devastating pig diseases, against which there is no vaccine available. recent work from our laboratory has demonstrated the protective potential of dna vaccines encoding three african swine fever viral antigens (p54, p30, and the hemagglutinin extracellular domain) fused to ubiquitin. partial protection was afforded in the absence of detectable antibodies prior to virus challenge, and survival correlated with the presence of a large number of hemagglutinin- ... | 2014 | 25210179 |
| genetic variation among african swine fever genotype ii viruses, eastern and central europe. | african swine fever virus (asfv) was first reported in eastern europe/eurasia in 2007. continued spread of asfv has placed central european countries at risk, and in 2014, asfv was detected in lithuania and poland. sequencing showed the isolates are identical to a 2013 asfv from belarus but differ from asfv isolated in georgia in 2007. | 2014 | 25148518 |
| vaccine potential of two previously uncharacterized african swine fever virus isolates from southern africa and heterologous cross protection of an avirulent european isolate. | african swine fever (asf) is a mostly fatal viral infection of domestic pigs for which there is no vaccine available. the disease is endemic to most of sub-saharan africa, causes severe losses and threatens food security in large parts of the continent. naturally occurring attenuated asf viruses have been tested as vaccine candidates, but protection was variable depending on the challenge virus. in this study, the virulence of two african isolates, one from a tick vector and the other from an in ... | 2016 | 25073549 |
| drivers and risk factors for circulating african swine fever virus in uganda, 2012-2013. | we explored observed risk factors and drivers of infection possibly associated with african swine fever (asf) epidemiology in uganda. representative sub-populations of pig farms and statistics were used in a case-control model. indiscriminate disposal of pig viscera and waste materials after slaughter, including on open refuse dumps, farm-gate buyers collecting pigs and pig products from within a farm, and retention of survivor pigs were plausible risk factors. wire mesh-protected windows in pig ... | 2014 | 25066802 |
| suitability of faeces and tissue samples as a basis for non-invasive sampling for african swine fever in wild boar. | a challenging aspect of asfv control in wild boar populations is the design and implementation of effective surveillance and monitoring programmes, both for early warning, and to determine the ongoing epidemiological situation in an infected population. testing blood samples requires invasive sampling strategies like hunting or capture of wild boar. besides being biased towards healthy animals, such strategies are also linked to further spread of the virus. non-invasive sampling strategies would ... | 2014 | 25017975 |
| no evidence of african swine fever virus replication in hard ticks. | african swine fever (asf) is caused by african swine fever virus (asfv), a tick-borne dna virus. soft ticks of the genus ornithodoros are the only biological vectors of asfv recognized so far. although other hard ticks have been tested for vector competence, two commonly found tick species in europe, ixodes ricinus and dermacentor reticulatus, have not been assessed for their vector competence for asfv. in this study, we aimed to determine whether virus replication can occur in any of these two ... | 2014 | 24980962 |
| modern adjuvants do not enhance the efficacy of an inactivated african swine fever virus vaccine preparation. | african swine fever (asf) is among the most devastating viral diseases of pigs. in recent years, the disease has spread alarmingly. despite intensive research activities, promising vaccine candidates are still lacking. for this reason, a study was undertaken to re-assess inactivated asfv preparations with state-of-the-art adjuvants. inactivated preparations of asf virus (asfv) "armenia08" were adjuvanted with either polygen™ or emulsigen(®)-d, respectively, and used to immunize six weaner pigs t ... | 2014 | 24877766 |
| a novel bromodeoxyuridine-resistant wild boar lung cell line facilitates generation of african swine fever virus recombinants. | 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 lun ... | 2014 | 24793370 |
| arboviruses pathogenic for domestic and wild animals. | the objective of this chapter is to provide an updated and concise systematic review on taxonomy, history, arthropod vectors, vertebrate hosts, animal disease, and geographic distribution of all arboviruses known to date to cause disease in homeotherm (endotherm) vertebrates, except those affecting exclusively man. fifty arboviruses pathogenic for animals have been documented worldwide, belonging to seven families: togaviridae (mosquito-borne eastern, western, and venezuelan equine encephaliliti ... | 2014 | 24751197 |
| a new nanopcr molecular assay for detection of porcine bocavirus. | nanoparticle-assisted polymerase chain reaction (nanopcr) is a novel method for the rapid amplification of dna and has been used for the detection of virus. for detection of porcine bocavirus (pbov), a sensitive and specific nanopcr assay was developed with a pair of primers that were designed based on ns1 gene sequences available in genbank. under the optimized conditions of the pbov nanopcr assay, the nanopcr assay was 100-fold more sensitive than a conventional pcr assay. the lower detection ... | 2014 | 24642242 |
| how a low-fidelity dna polymerase chooses non-watson-crick from watson-crick incorporation. | a dogma for dna polymerase catalysis is that the enzyme binds dna first, followed by mgdntp. this mechanism contributes to the selection of correct dntp by watson-crick base pairing, but it cannot explain how low-fidelity dna polymerases overcome watson-crick base pairing to catalyze non-watson-crick dntp incorporation. dna polymerase x from the deadly african swine fever virus (pol x) is a half-sized repair polymerase that catalyzes efficient dg:dgtp incorporation in addition to correct repair. ... | 2014 | 24617852 |
| correlation of cell surface marker expression with african swine fever virus infection. | the expression of surface markers on african swine fever virus (asfv) infected cells was evaluated to assess their involvement in infection. previous findings indicated cd163 expression was correlated with asfv susceptibility. however, in this study the expression of porcine cd163 on cell lines did not increase the infection rate of these cells indicating other factors are likely to be important in determining susceptibility to infection. on adherent porcine bone marrow (pbm) cells the expressio ... | 2014 | 24398227 |
| first molecular assessment of the african swine fever virus status of ornithodoros ticks from swaziland. | african swine fever (asf) is an economically significant haemorrhagic disease of domestic pigs. it is caused by the african swine fever virus (asfv), a deoxyribonucleic acid (dna)arbovirus. argasid ticks of the genus ornithodoros, which are widely distributed throughout southern africa, play a primary role in virus maintenance and spread within the endemic sylvatic cycle. the asf status of swaziland is unknown, but this land-locked country is surrounded by asf-positive countries, has a burgeonin ... | 2014 | 26304186 |
| [real-time pcr kits for the detection of the african swine fever virus]. | the results obtained using the diagnostic kit based on real-time polymerase chain reaction to detect the dna of the african swine fever in the pathological material, as well as in the culture fluid, are presented. a high sensitivity and specificity for detection of the dna in the organs and tissues of animals was shown to be useful for detection in the european union referentiality reagent kits for dna detection by real time pcr of asfv. more rapid and effective method of dna extraction using co ... | 2014 | 25895212 |
| prevalence of african swine fever virus in apparently healthy domestic pigs in uganda. | 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 ... | 2013 | 24369729 |
| how dna polymerase x preferentially accommodates incoming datp opposite 8-oxoguanine on the template. | the modified base 8-oxo-7,8-dihydro-2'-deoxyguanosine (oxog) is a common dna adduct produced by the oxidation of dna by reactive oxygen species. kinetic data reveal that dna polymerase x (pol x) from the african swine fever virus incorporates adenine (datp) opposite to oxog with higher efficiency than the non-damaged g:c basepair. to help interpret the kinetic data, we perform molecular dynamics simulations of pol x/dna complexes, in which the template base opposite to the incoming dntp (dctp, d ... | 2013 | 24314086 |
| 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. | 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 f ... | 2013 | 24076499 |
| african swine fever virus: on the move and dangerous. | | 2013 | 24038277 |
| comprehensive phylogenetic reconstructions of african swine fever virus: proposal for a new classification and molecular dating of the virus. | 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 s ... | 2013 | 23936068 |
| development and validation of a multiplex, real-time rt pcr assay for the simultaneous detection of classical and african swine fever viruses. | a single-step, multiplex, real-time polymerase chain reaction (rt-pcr) was developed for the simultaneous and differential laboratory diagnosis of classical swine fever virus (csfv) and african swine fever virus (asfv) alongside an exogenous internal control rna (ic-rna). combining a single extraction methodology and primer and probe sets for detection of the three target nucleic acids csfv, asfv and ic-rna, had no effect on the analytical sensitivity of the assay and the new triplex rt-pcr was ... | 2013 | 23923045 |
| a nanoparticle-assisted pcr assay to improve the sensitivity for rapid detection and differentiation of wild-type pseudorabies virus and gene-deleted vaccine strains. | nanoparticle-assisted polymerase chain reaction (nanopcr) is a novel method for the rapid amplification of dna and has been adopted for the detection of virus because of its simplicity, rapidity, and specificity. a nanopcr assay was developed to detect and differentiate wild-type and gene-deleted pseudorabies virus (prv). three pairs of primers for nanopcr developed in this study were selected from conserved regions of prv, producing specific amplicons of 431 bp (gb), 316 bp (ge), and 202 bp (gg ... | 2013 | 23872268 |
| involvement of the reparative dna polymerase pol x of african swine fever virus in the maintenance of viral genome stability in vivo. | the function of the african swine fever virus (asfv) reparative dna polymerase, pol x, was investigated in the context of virus infection. pol x is a late structural protein that localizes at cytoplasmic viral factories during dna replication. using an asfv deletion mutant lacking the pol x gene, we have shown that pol x is not required for virus growth in vero cells or swine macrophages under one-step growth conditions. however, at a low multiplicity of infection, when multiple rounds of replic ... | 2013 | 23824796 |
| phytochemical analysis and in-vitro anti-african swine fever virus activity of extracts and fractions of ancistrocladus uncinatus, hutch and dalziel (ancistrocladaceae). | african swine fever (asf), a highly contagious fatal acute haemorrhagic viral disease of pigs currently has no treatment or vaccination protocol and it threatens the pig industry worldwide. recent outbreaks were managed by farmers with ethnoveterinary preparations with various claims of effectiveness. | 2013 | 23777548 |
| prospects for development of african swine fever virus vaccines. | african swine fever virus is a large dna virus which can cause an acute haemorrhagic fever in pigs resulting in high mortality. no vaccine is available, limiting options for control. the virus encodes up to 165 genes and virus particles are multi-layered and contain more than 50 proteins. pigs immunised with natural low virulence isolates or attenuated viruses produced by passage in tissue culture and by targeted gene deletions can be protected against challenge with virulent viruses. cd8+ cells ... | 2013 | 23689892 |
| transmission rate of african swine fever virus under experimental conditions. | african swine fever (asf) is a highly lethal, viral disease of swine. no vaccine is available, so controlling an asf outbreak is highly dependent on zoosanitary measures, such as stamping out infected herds and quarantining of affected areas. information on asf transmission parameters could allow for more efficient application of outbreak control measures. three transmission experiments were carried out to estimate the transmission parameters of two asf virus isolates: malta'78 (in two doses) an ... | 2013 | 23664069 |
| antigen targeting to apc: from mice to veterinary species. | antigen delivery to receptors expressed on antigen presenting cells (apc) has shown to improve immunogenicity of vaccines in mice. an enhancement of cytotoxic t lymphocyte (ctl), helper t cell or humoral responses was obtained depending on the type of apc and the surface molecule targeted. although this strategy is being also evaluated in livestock animals with promising results, some discrepancies have been found between species and pathogens. the genetic diversity of livestock animals, the dif ... | 2013 | 23648645 |
| quantification of airborne african swine fever virus after experimental infection. | knowledge on african swine fever (asf) transmission routes can be useful when designing control measures against the spread of asf virus (asfv). few studies have focused on the airborne transmission route, and until now no data has been available on quantities of asf virus (asfv) in the air. our aim was to validate an air sampling technique for asf virus (asfv) that could be used to detect and quantify virus excreted in the air after experimental infection of pigs. in an animal experiment with t ... | 2013 | 23608475 |
| detection of african swine fever virus dna in blood samples stored on fta cards from asymptomatic pigs in mbeya region, tanzania. | 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 duplica ... | 2015 | 23472656 |
| bacmam immunization partially protects pigs against sublethal challenge with african swine fever virus. | 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 protei ... | 2013 | 23428670 |
| in vitro antiviral activity of fluoroquinolones against african swine fever virus. | african swine fever (asf) is a viral swine disease against which neither an effective vaccine nor a treatment is available. the antiviral effect of thirty fluoroquinolones on the infectivity of african swine fever virus (asfv) was screened in vitro. there was a severe reduction of the cytopathic effect in asfv-infected vero cells when exposed to six independent fluoroquinolones, or to some of their combinations, from an early phase of infection. moreover, after 7-day treatments, asfv genome coul ... | 2013 | 23415476 |
| asfv in tanzania: asymptomatic pigs harbor virus of molecular similarity to georgia 2007. | in 2011 african swine fever virus (asfv) genome was detected in asymptomatic pigs in field samples in mbeya, tanzania. the aim of this paper is to partly characterize the virus that was harbored in these pigs and furthermore to confirm, by a second sampling, the latest occurrence of asfv in the study area. asfv genome was detected in serum from 10 out of 127 healthy european/crossbreed pigs. asfv dna was polymerase chain reaction (pcr) amplified and sequenced from sera with high viral loads usin ... | 2013 | 23398669 |
| host dna damage response facilitates african swine fever virus infection. | studies with different viral infection models on virus interactions with the host cell nucleus have opened new perspectives on our understanding of the molecular basis of these interactions in african swine fever virus (asfv) infection. the present study aims to characterize the host dna damage response (ddr) occurring upon in vitro infection with the asfv-ba71v isolate. we evaluated protein levels during asfv time-course infection, of several signalling cascade factors belonging to ddr pathways ... | 2013 | 23398667 |
| african swine fever virus conquers new territories. | | 2013 | 23376880 |
| detection of african swine fever virus-like sequences in ponds in the mississippi delta through metagenomic sequencing. | metagenomic characterization of water virome was performed in four mississippi catfish ponds. although differing considerably from african swine fever virus (asfv), 48 of 446,100 sequences from 12 samples were similar enough to indicate that they represent new members in the family asfarviridae. at present, asfv is the only member of asfarviridae, and this study presents the first indication of a similar virus in north america. at this point, there is no indication that the identified virus(es) ... | 2013 | 23338931 |
| standardization of pathological investigations in the framework of experimental asfv infections. | african swine fever is still one of the major viral diseases of swine for which a commercial vaccine is lacking. for the design and development of such preventive products, researchers involved in african swine fever virus (asfv) vaccinology need standardized challenge protocols and well characterized clinical, pathological and immunological responses of inbreed and outbreed pigs to different viral strains and vaccine-like products. the different approaches used should be assessed by immunologis ... | 2013 | 23313935 |
| african swine fever virus organelle rearrangements. | like most viruses african swine fever virus (asfv) subsumes the host cell apparatus in order to facilitate its replication. asfv replication is a highly orchestrated process with a least four stages of transcription, immediate-early, early, intermediate and late. as the infective cycle progresses through these stages most if not all of the organelles that comprise a nucleated cell are modified, adapted or in some cases destroyed. the entry of the virus is receptor-mediated, but the precise mecha ... | 2013 | 23291273 |
| a179l, a new viral bcl2 homolog targeting beclin 1 autophagy related protein. | autophagy is a relevant cellular defense mechanism that directly eliminates intracellular pathogens and has a crucial role for innate and adaptive immune responses. some viruses have developed tools to counteract this cellular response. a179l, the viral bcl2 homolog of african swine fever virus, interacts with proapoptotic bcl2 family proteins to inhibit apoptosis. here we report that this gene manipulates autophagy by interacting with beclin 1 through its bh3 homology domain. at subcellular lev ... | 2013 | 23228131 |
| comparison of african swine fever virus prevalence and risk in two contrasting pig-farming systems in south-west and central kenya. | we describe a horizontal survey of african swine fever virus (asfv) prevalence and risk factors associated with virus infection in domestic pigs in two contrasting production systems in kenya. a free range/tethering, low input production system in ndhiwa district of south-western kenya is compared with a medium input stall fed production system in kiambu district of central kenya. analysis of variance (anova) of data derived from cluster analysis showed that number of animals, number of breeding ... | 2013 | 23219357 |
| cellular immunity in asfv responses. | african swine fever virus (asfv) infection usually results in an acute haemorrhagic disease with a mortality rate approaching 100% in domestic pigs. however, pigs can survive infection with less-virulent isolates of asfv and may become chronically infected. surviving animals are resistant to challenge with homologous or, in some cases, closely related isolates of the virus indicating that pigs can develop protective immunity against asfv. during asymptomatic, non-virulent asfv infections natural ... | 2013 | 23201582 |
| african swine fever virus, tanzania, 2010-2012. | | 2012 | 23171814 |
| identification and utility of innate immune system evasion mechanisms of asfv. | the interferon (ifn) system is an early innate anti-virus host defense mechanism that takes place shortly after entry of the pathogen and long before the onset of adaptive immunity. thus, african swine fever virus (asfv), as an acute and persistent virus in pigs, is predicted to have evolved multiple genes for the manipulation and evasion of interferon. although, asfv is known to interfere with signaling pathways controlling the transcription of cytokines, surprisingly no individual virus gene m ... | 2013 | 23165138 |
| particle tracking analysis for the intracellular trafficking of nanoparticles modified with african swine fever virus protein p54-derived peptide. | previous studies showed that the cytoplasmic transport of nanoparticles to the nucleus is driven by a vesicular sorting system. artificial approaches for targeting a microtubule-associating motor complex is also a challenge. we describe herein the development of a liposomal nanoparticle, the surface of which is modified with stearylated octa-arginine (str-r8), and a dynein light chain (lc8)-associated peptide derived from an african swine fever virus protein p54 (p54(149-161)) with polyethyleneg ... | 2013 | 23164937 |
| a comparative analysis on the synonymous codon usage pattern in viral functional genes and their translational initiation region of asfv. | the synonymous codon usage pattern of african swine fever virus (asfv), the similarity degree of the synonymous codon usage between this virus and some organisms and the synonymous codon usage bias for the translation initiation region of viral functional genes in the whole genome of asfv have been investigated by some simply statistical analyses. although both gc12% (the gc content at the first and second codon positions) and gc3% (the gc content at the third codon position) of viral functional ... | 2013 | 23161403 |
| antibody-mediated neutralization of african swine fever virus: myths and facts. | almost all viruses can be neutralized by antibodies. however, there is some controversy about antibody-mediated neutralization of african swine fever virus (asfv) with sera from convalescent pigs and about the protective relevance of antibodies in experimentally vaccinated pigs. at present, there is no vaccine available for this highly lethal and economically relevant virus and all classical attempts to generate a vaccine have been unsuccessful. this failure has been attributed, in part, to what ... | 2013 | 23159730 |
| african swine fever virus controls the host transcription and cellular machinery of protein synthesis. | throughout a viral infection, the infected cell reprograms the gene expression pattern in order to establish a satisfactory antiviral response. african swine fever virus (asfv), like other complex dna viruses, sets up a number of strategies to evade the host's defense systems, such as apoptosis, inflammation and immune responses. the capability of the virus to persist in its natural hosts and in domestic pigs, which recover from infection with less virulent isolates, suggests that the virus disp ... | 2013 | 23154157 |
| african swine fever virus replication and genomics. | african swine fever virus (asfv) is a large icosahedral dna virus which replicates predominantly in the cytoplasm of infected cells. the asfv double-stranded dna genome varies in length from about 170 to 193 kbp depending on the isolate and contains between 150 and 167 open reading frames. these are closely spaced and read from both dna strands. the virus genome termini are covalently closed by imperfectly base-paired hairpin loops that are present in two forms that are complimentary and inverte ... | 2013 | 23142553 |
| african swine fever virus eradication in africa. | african swine fever was reported in domestic pigs in 26 african countries during the period 2009-2011. the virus exists in an ancient sylvatic cycle between warthogs (phacochoerus africanus) and argasid ticks of the ornithodoros moubata complex in many of the countries reporting outbreaks and in two further countries in the region. eradication of the virus from the countries in eastern and southern africa where the classic sylvatic cycle occurs is clearly not an option. however, the virus has be ... | 2013 | 23142552 |
| virological diagnosis of african swine fever--comparative study of available tests. | the rapid and reliable detection of african swine fever virus (asfv) is essential both for timely implementation of control measures to prevent the spread of disease, and to differentiate african swine fever (asf) from other pig disease with similar clinical presentations. many virological tests are currently available for the detection of asfv (live virus), antigen and genome, including virus isolation, elisa, fluorescent antibody, polymerase chain reaction (pcr) and isothermal assays. in recen ... | 2013 | 23131492 |
| african swine fever virus serodiagnosis: a general review with a focus on the analyses of african serum samples. | african swine fever (asf) is an infectious disease that causes heavy mortality in domestic pigs. at present there is no vaccine against asf, and eradication in countries where the disease is endemic is based only on competent diagnosis programs and the sacrifice of infected animals. due to the presence of natural attenuated strains, certain infection conditions may result in reduced mortality. in these situations, the disease can be diagnosed by detection of specific antibodies. the use of class ... | 2013 | 23131491 |
| epidemiology of african swine fever virus. | african swine fever virus used to occur primarily in africa. there had been occasional incursions into europe or america which apart from the endemic situation on the island of sardinia always had been successfully controlled. but following an introduction of the virus in 2007, it now has expanded its geographical distribution into caucasus and eastern europe where it has not been controlled, to date. african swine fever affects domestic and wild pig species, and can involve tick vectors. the ab ... | 2013 | 23123296 |
| african swine fever virus infection in ornithodoros ticks. | african swine fever virus (asfv) is an arbovirus which is vectored by soft ticks of the ornithodoros spp. and in the sylvatic cycle infects wart hogs and bush pigs. asfv infection of domestic swine causes a high mortality disease. on the other hand, asfv infection of the tick can result in a high-titered and persistent infection depending upon the asfv isolate and the tick combination. recently, morphological, classical virology (titration) and recombinant asfv have been used to study the cellul ... | 2013 | 23085123 |
| african swine fever virus morphogenesis. | this review summarizes recent structural and molecular biology studies related to the morphogenesis of african swine fever virus (asfv). asfv possesses icosahedral morphology and is constituted by four concentric layers: the central nucleoid, the core shell, the inner envelope and the icosahedral capsid. the extracellular virus acquires an external envelope by budding through the plasma membrane. the genes coding for 19 of the 54 structural proteins of the asfv particle are known and the localiz ... | 2013 | 23059353 |
| dna vaccination partially protects against african swine fever virus lethal challenge in the absence of antibodies. | the lack of available vaccines against african swine fever virus (asfv) means that the evaluation of new immunization strategies is required. here we show that fusion of the extracellular domain of the asfv hemagglutinin (sha) to p54 and p30, two immunodominant structural viral antigens, exponentially improved both the humoral and the cellular responses induced in pigs after dna immunization. however, immunization with the resulting plasmid (pcmv-shapq) did not confer protection against lethal c ... | 2012 | 23049728 |
| laboratory methods to study african swine fever virus. | we summarize findings of comparative studies in different cells cultures susceptible to asfv infection, through the analysis of virus components and infectious virus particles production, as alternative means to grow field and laboratory asfv strains. we also provide different methods to assay the infectivity of asfv samples and to purify the infective virus particles. finally we describe the general strategy to construct virus deletion mutants that can be engineered to obtain attenuated asfv st ... | 2013 | 23041357 |
| african swine fever virus transcription. | african swine fever virus (asfv), a large, enveloped, icosahedral dsdna virus, is currently the only known dna-containing arbovirus and the only recognized member of the family asfarviridae. its genome encodes more than 150 open reading frames that are densely distributed, separated by short intergenic regions. asfv gene expression follows a complex temporal programming. four classes of mrnas have been identified by its distinctive accumulation kinetics. gene transcription is coordinated with dn ... | 2013 | 23041356 |
| [dynamics of changes in the composition of leukocyte population of peripheral blood during the african swine fever]. | the comparison of the composition of leukocytes of peripheral blood of healthy and infected swine revealed the quantitative alterations, as well as the appearance of new cells in leukocyte population during african swine fever. it was determined that african swine fever virus induced mass-scale mortality of cells of peripheral blood, especially lymphocytes and neutrophiles. the number of the dead cells reaches 60% of the initial number of all cells at the end of infection. it was also revealed t ... | 2016 | 23012981 |
| comparative evaluation of novel african swine fever virus (asf) antibody detection techniques derived from specific asf viral genotypes with the oie internationally prescribed serological tests. | the presence of antibodies against african swine fever (asf), a complex fatal notifiable oie disease of swine, is always indicative of previous infection, since there is no vaccine that is currently used in the field. the early appearance and subsequent long-term persistence of antibodies combined with cost-effectiveness make antibody detection techniques essential in control programmes. recent reports appear to indicate that the serological tests recommended by the oie for asf monitoring are mu ... | 2013 | 22944073 |