The overwintering mechanism of bluetongue virus (BTV) has eluded researchers for many years. While overwintering in the vertebrate host has been the favored hypothesis, it has been shown that several arboviruses overwinter in their invertebrate vectors. Overwintering _Culicoides sonorensis_ larvae...
Maclachlan, N J; Mayo, C E; Daniels, P W; Savini, G; Zientara, S; Gibbs, E P J
Summary Bluetongue (BT) is an arthropod-transmitted viral disease of non-African ungulates, principally sheep. The disease results from vascular injury analogous to that of human haemorrhagic viral fevers, with characteristic tissue infarction, haemorrhage, vascular leakage, oedema, and hypovolaemic shock. Importantly, BT is not zoonotic. Bluetongue virus (BTV) infection of ruminants and vector Culicoides midges is endemic throughout many tropical and temperate regions of the world; however, within this global range the virus exists within relatively discrete ecosystems (syn. episystems) where specific constellations of BTV serotypes are spread by different species of biting Culicoides midges. Recently discovered goat-associated BTVs, notably BTV serotype 25 (BTV-25) in central Europe, appear to have distinctive biological properties and an epidemiology that is not reliant on Culicoides midges as vectors for virus transmission. Bluetongue virus infection of ruminants is often subclinical, but outbreaks of severe disease occur regularly at the upper and lower limits of the virus's global range, where infection is distinctly seasonal. There have been recent regional alterations in the global distribution of BTV infection, particularly in Europe. It is proposed that climate change is responsible for these events through its impact on vector midges. However, the role of anthropogenic factors in mediating emergence of BTV into new areas remains poorly defined; for example, it is not clear to what extent anthropogenic factors were responsible for the recent translocation to northern and eastern Europe of live attenuated vaccine viruses and an especially virulent strain of BTV-8 with distinctive properties. Without thorough characterisation of all environmental and anthropogenic drivers of the recent emergence of BT in northern Europe and elsewhere, it is difficult to predict what the future holds in terms of global emergence of BTV infection. Accurate and convenient
Lee, Fan; Ting, Lu-Jen; Lee, Ming-Shiuh; Chang, Wei-Ming; Wang, Fun-In
BTV2/KM/2003 and BTV12/PT/2003 are the first identified bluetongue viruses in Taiwan. The prototype virus BTV2/KM/2003 was previously characterized in various respects as low virulent. In the present study, nucleotide sequences of the ten genome segments and their coding regions of the Taiwan strains were determined and analyzed. The two strains had >96.8% nucleotide and >97.9% deduced amino acid identities to each other, except for the VP2 genes. Their genome sequences, except for NS1 and VP2 genes, clustered overall in the Asian lineage, and were closely related to strains from China, India, Indonesia, and Japan. The phylogenetic trees and nucleotide identities of six BTV genes were suggestive of the geographical origin of the bluetongue virus strains analyzed, with a few exceptions. To examine which genes better distinguished strains from different origins (topography), the distribution of and the levels of differences in nucleotide identities were analyzed, revealing that VP3, NS2, and NS3 genes were more suitable for topotyping of BTVs. Analysis of ratios of non-synonymous/synonymous substitutions (dN/dS values) between putative ancestry and their descendant strains suggested that most BTV genes evolved under a negative selection, whereas the VP7 gene evolved under positive selection, and its non-synonymous substitutions accumulated more rapidly in strains from the Mediterranean region. PMID:20855174
Bouwknegt, C.; Rijn, van, Michela; Schipper, J.M.J.; Holzel, D.R.; Boonstra, J.; Nijhof, A.; de, Rooij, R.; Jongejan, F.
When the first outbreak of bluetongue virus serotype 8 (BTV8) was recorded in North-West Europe in August 2006 and renewed outbreaks occurred in the summer of 2007 and again in 2008, the question was raised how the virus survived the winter. Since most adult Culicoides vector midges are assumed not to survive the northern European winter, and transovarial transmission in Culicoides is not recorded, we examined the potential vector role of ixodid and argasid ticks for bluetongue virus. Four sp...
Bouwknegt, C.; Rijn, van P.A.; Schipper, J.M.J.; Holzel, D.R.; Boonstra, J.; Nijhof, A.; Rooij, van E.M.A.; Jongejan, F.
When the first outbreak of bluetongue virus serotype 8 (BTV8) was recorded in North-West Europe in August 2006 and renewed outbreaks occurred in the summer of 2007 and again in 2008, the question was raised how the virus survived the winter. Since most adult Culicoides vector midges are assumed not
Bluetongue viruses (BTVs) are economically important arboviruses that affect sheep and cattle. The overwintering mechanism of BTVs in temperate climates has eluded researchers for many years. Many arboviruses overwinter in their invertebrate vectors. To test the hypothesis that BTVs overwinter in...
Osmani, A; Murati, B; Kabashi, Q; Goga, I; Berisha, B; Wilsmore, A J; Hamblin, C
In 2001, clinical cases of bluetongue were observed in Kosovo, and in that year and in 2003 and 2004, serum samples were collected from cattle and small ruminants and tested for antibodies to bluetongue virus. The results provide evidence that bluetongue virus was not present in Kosovo before the summer of 2001, but that the virus circulated subclinically among the cattle and sheep populations of Kosovo in 2002, 2003 and 2004. PMID:16565337
Bluetongue virus (BTV) is an arthropod-borne Orbivirus that infects domestic and wild ruminants. Worldwide, there are at least 24 serotypes and numerous strains within each serotype. Bluetongue virus has 10 double-stranded genome segments that encode the viral structural and non-structural proteins...
Rijn, van Piet A.; Water, van de Sandra G.P.; Feenstra, Femke; Gennip, van René G.P.
Background: Bluetongue virus (BTV) and African horse sickness virus (AHSV) are distinct arthropod borne virus species in the genus Orbivirus (Reoviridae family), causing the notifiable diseases Bluetongue and African horse sickness of ruminants and equids, respectively. Reverse genetics systems f
Drolet, B.S.; Reister, L.M.; Mecham, J.O.; Wilson, W.C.; Nol, P.; Vercauteren, K.C.; Rijn, van P.A.; Bowen, R.A.
Bluetongue (BT) is an insect-transmitted, economically important disease of domestic and wild ruminants. Although only five of the 26 reported bluetongue virus (BTV) serotypes are considered endemic to the USA, 10 exotic serotypes have been isolated primarily in the southeastern region of the countr
Poli, G.; Stott, J.; Liu, Y. S.; Manning, J S
Comparative studies on the detection of bovine serum immunoglobulin G antibodies to bluetongue virus with an enzyme-linked immunosorbent assay, an immunodiffusion method, and a serum neutralization assay demonstrated complete concordance between the enzyme-linked immunosorbent assay and the serum neutralization assay results. However, the immunodiffusion method failed to detect bluetongue virus antibody in a substantial number of sera found to possess bluetongue virus immunoglobulin G with th...
Virus isolation, antigen detection, and in situ hybridization were compared in their abilities to detect in cell culture, the five serotypes of bluetongue virus (BTV) occurring in the United States, serotypes 2, 10, 11, 13, and 17. For isolation, virus was propagated in baby hamster kidney (BHK-21) cell culture. For antigen detection, two techniques, indirect fluorescent-antibody (IFA) and enzyme immunocytoassay (EICA) were used. For in situ hybridization, a complementary DNA (cDNA) of the L3 RNA genome segment of BTV, serotype 17 (BTV-17) labeled with 35S was used as a group-specific probe. Virus isolation was the most sensitive technique, often detecting input virus and then detecting virus throughout the course of the study. IFA and EICA were of similar sensitivity and detected BTV antigen shortly after detection of virus by isolation. A direct-blot hybridization technique using a 32P-labeled, strand-specific RNA transcript probe was developed, optimized, and used to detect BTV in pools of infected Culicoides variipennis midges. The technique was able to detect as few as one infected Culicoides midge in a pool of 100 and as little as 3.5 log10 TCID50 per ml of virus. A sandwich hybridization technique was developed and used to detect BTV in pools of infected Culicoides variipennis midges. The sandwich hybridization technique used a single-stranded DNA catcher sequence bound to a solid support and a 32P-labeled, single-stranded RNA detector sequence. Sandwich hybridization was compared to direct blot hybridization using a strand-specific RNA transcript probe or a cDNA probe. Sandwich hybridization was able to detect as few as one infected Culicoides midge in a pool of 50; however, the technique was approximately tenfold less sensitive than direct blot hybridization
Venter, Estelle H; Truuske Gerdes; Isabel Wright; Johan Terblanche
Bluetongue (BT), a disease that affects mainly sheep, causes economic losses owing to not only its deleterious effects on animals but also its associated impact on the restriction of movement of livestock and livestock germplasm. The causative agent, bluetongue virus (BTV), can occur in the semen of rams and bulls at the time of peak viraemia and be transferred to a developing foetus. The risk of the transmission of BTV by bovine embryos is negligible if the embryos are washed according ...
Bluetongue (BT) is a Culicoides-born infectious disease caused by bluetongue virus (BTV). From 2006 to 2010, BTV serotype 8 (BTV-8) spread throughout Europe, causing severe disease in domestic and some wild ruminant species and in an alpaca. Compulsory vaccination of susceptible animals was the most effective strategy to control and eradicate the BTV-8 epizootic in Europe. However, South American camelids (SAC) were not included in the BTV-8 vaccination programmes in Europe. The presented...
Veerakyathappa Bhanuprakash; Madhusudhan Hosamani; Vinayagamurthy Balamurugan; Pradeep Narayan Gandhale; Gnanavel Venkatesan; Raj Kumar Singh
In the present study, a total of 24 Mabs were produced against bluetongue virus (BTV) by polyethyleneglycol (PEG) mediated fusion method using sensitized lymphocytes and myeloma cells. All these clones were characterized for their reactivity to whole virus and recombinant BTV-VP7 protein, titres, isotypes and their reactivity with 24 BTV-serotype specific sera in cELISA. Out of 24 clones, a majority of them (n = 18)belong to various IgG subclasses and the remaining (n = 6) to the IgM class. A panel of eight clones reactive to both whole BTV and purified rVP7 protein were identified based on their reactivity in iELISA. For competitive ELISA, the clone designated as 4A10 showed better inhibition to hyperimmune serum of BTV serotype 23. However, this clone showed a variable percent of inhibition ranging from 16.6% with BTV 12 serotype to 78.9% with BTV16 serotype using 24 serotype specific sera of BTV originating from guinea pig at their lowest dilutions. From the available panel of clones, only 4A 10 was found to have a possible diagnostic application.
Wechsler, S J; Luedke, A. J.
Two systems, inoculation of bovine endothelial cells and of embryonated chicken eggs, were compared for detection of bluetongue virus (BTV) in blood specimens from experimentally inoculated sheep. For all BTV serotypes tested, embryonated chicken eggs detected longer periods of viremia than did bovine endothelial cells, primarily by detecting BTV in samples containing lower virus concentrations.
Bumbarov, Velizar; Golender, Natalia; Erster, Oran; Khinich, Yevgeny
In this report we describe the detection and identification of Bluetongue virus (BTV) contaminations in commercial vaccines. BTV RNA was detected in vaccine batches of Lumpy skin disease (LSD) and Sheep pox (SP) using quantitative PCR (qPCR) for VP1 and NS3 genes. Both batches were positive for VP1 and NS3 in qPCR. The LSD vaccine-derived sample was positive for VP1 and VP2 in conventional PCR. The SP vaccine-derived sample was examined by amplification of VP1, VP4, VP6, VP7, NS2 and NS3 gene segments in conventional PCR. The SP vaccine-derived sample was further propagated in embryonated chicken eggs (ECE) and Vero cells. Preliminary sequence analysis showed that the LSD vaccine-derived sequence was 98-99% similar to BTV9. Analysis of the six genomic segments from the SP vaccine-derived isolate showed the highest similarity to BTV26 (66.3-97.8%). These findings are particularly important due to the effect of BTV on cattle and sheep, for which the vaccines are intended. They also demonstrate the necessity of rigorous vaccine inspection and strict vaccine production control. PMID:27171751
In monitoring of sentinel cattle in West Java, seroconversions to orbiviruses occurred mostly at the end of the wet season. A low altitude site gave more reactors than did a high altitude site. Due to perceived inefficiencies of the agar gel immunodiffusion (AGID) test, a competitive ELISA (C-ELISA) was applied and the results compared with the AGID test results. C-ELISA detected antibodies at an earlier stage of infection than did the AGID test. Not all sera reacting in the AGID test reacted in C-ELISA, suggesting that the C-ELISA is more specific in detecting bluetongue virus (BTV) antibodies than the AGID. However, as the infection status of most field sera was not known, this could not be confirmed conclusively from the available data. A comparison of isolation methods indicated that isolates were obtained more frequently if samples were passaged in embryonated eggs before blind passage in A edes albopictus cells followed by passage in BHK-21 cells. Six BTV serotypes, 1,7,9,12,20,21 and 23 were identified and confirmed from apparently healthy sentinel cattle blood at low altitudes; BTV serotype 21 was also isolated from a pool of the Avaritia sub-genus of the Culicoides spp which contained 227 C. fulvus and 20 C. orientalis. (author). 17 refs, 2 figs, 1 tab
A competitive enzyme-linked immunosorbent assay (C-ELISA) was used to conduct surveillance of bluetongue virus antibodies (BTV) in sheep, goats and cattle in Mongolia. The highest prevalence was recorded in goats (86%) followed by sheep (51%) and cattle (9%). The results are the first confirmation of the presence of such antibodies in Mongolian livestock. Studies are now underway to conduct more detailed investigations concerning bluetongue, including to determine the virus serotypes that are and have been circulating in the country. (author)
Mayo, Christie E.; Crossley, Beate M.; Hietala, Sharon K.; Gardner, Ian A; Breitmeyer, Richard E.; Maclachlan, N. James
There have been substantial recent changes in the global distribution and nature of bluetongue virus (BTV) infection of ungulates, perhaps as a result of climate change. To evaluate the epidemiology of BTV infection in California, an area historically endemic for the virus, we monitored newborn dairy calves at different sites for one year for the presence of BTV RNA and virus-specific antibodies. The data confirm both localized, vector-mediated, seasonal transmission of BTV as well as dissemi...
Sluijs, van der M.T.W.; Schroer-Joosten, D.P.H.; Fid-Fourkour, A.; Vrijenhoek, M.P.; Debyser, I.; Moulin, V.; Moormann, R.J.M.; Smit, de A.J.
The Bluetongue virus serotype 8 (BTV-8) strain, which emerged in Europe in 2006, had an unusually high ability to cause foetal infection in pregnant ruminants. Other serotypes of BTV had already been present in Europe for more than a decade, but transplacental transmission of these strains had never
Ali Asghar Mozaffari; Mohammad Khalili
Objective: Bluetongue virus is an arthropod-borne Orbivirus in the family Reoviridae which infects both domestic and wild ruminants. Bluetongue disease is a "List A" disease of the Office of International Epizootics. To the best of our knowledge, no report has been published on bluetongue disease of sheep flocks of Southeast of Iran. The objective of this study was to describe the seroprevalence rates of BTV in sheep flocks in southeast of Iran. Methods: The blood samples were collected randomly from herds of Southeast of Iran. A total of 188 sera samples (94 male, 94 female) collected between 2009 and 2010, were available. Antibodies to BTV in sera were detected by using a commercial competitive ELISA (Institute Pourquier, Montpellier, France) according to manufacturer’s instructions. Results: The seroprevalence rates were 6.57 %for sheep herds. Within a herd, prevalence of BTV seropositive animals ranged from 0% to 42.85%. 33.3% sheep flocks were positive to BTV antibodies. Sex didn't affect the rate of seropositivity, but the rate of seropositivity was significantly changed in different age groups. Conclusion: This study describes the seroprevalence rates of Bluetongue virus (BTV) in sheep flocks in southeast of Iran for the first time.
Balaro, Mario Felipe Alvarez; Dos Santos Lima, Michele; Del Fava, Claudia; de Oliveira, Glenda Ribeiro; Pituco, Edviges Maristela; Brandão, Felipe Zandonadi
In late January 2013, 10 nonpregnant Lacaune dairy ewes raised under extensive husbandry management on a farm in Rio de Janeiro, Brazil, presented with the general clinical signs of lethargy, hyporexia, edema of the face, hyperemia of the exposed parts of the skin, mouth lesions, pyrexia, and lameness. Additionally, 2 pregnant ewes died suddenly after the onset of respiratory signs. The complete blood counts and biochemistry analyses showed neutrophilic leukocytosis with monocytosis and reactive lymphocytes, normocytic normochromic anemia and increased aspartate aminotransferase levels. Postmortem examination revealed erosions on the lingual mucosa, bilateral submandibular ganglia infarctions, yellow foamy fluid accumulation in the trachea and bronchial bifurcation, pulmonary congestion, and edema associated with hemorrhagic lesions on the pulmonary artery and heart. The clinical and pathological findings were suggestive of bluetongue. For a molecular and virological diagnosis, tissue samples were analyzed by Bluetongue virus-specific real-time reverse transcription polymerase chain reaction (qRT-PCR), and viral isolation was performed in embryonated chicken eggs. For viral typing, positive tissue and egg-isolated samples were analyzed by qRT-PCR using primers and probes specific for the structural VP2 gene in genome segment 2 of all 26 serotypes. There are still no contingency plans for responding to an outbreak of bluetongue disease in Brazil, and this episode emphasizes the need for continuing serological and entomological surveillance programs. Additionally, this report describes the isolation of Bluetongue virus serotype 4 in sheep in the Americas. PMID:24916443
Mayo, C E; Crossley, B M; Hietala, S K; Gardner, I A; Breitmeyer, R E; Maclachlan, N James
There have been substantial recent changes in the global distribution and nature of bluetongue virus (BTV) infection of ungulates, perhaps as a result of climate change. To evaluate the epidemiology of BTV infection in California, an area historically endemic for the virus, we monitored newborn dairy calves at different sites for 1 year for the presence of BTV RNA and virus-specific antibodies. The data confirm both localized, vector-mediated, seasonal transmission of BTV as well as dissemination of BTV and/or viral nucleic acid to newborn calves following ingestion of colostrum. PMID:20557494
Gamma irradiation is being tested as a means of inactivating bluetongue virus (BTV) for use in vaccines. Exposure of BTV 17 to various levels of irradiation revealed that a dose of approximately 0.6 megarad was required to reduce the virus titer by one log10, or 90%. To test the immunogenicity of irradiated BTV, mouse brain passaged virus and concentrated cell culture passaged virus were inactivated by 6 megarads of gamma irradiation, and vaccines were prepared by emulsifying the virus preparations in equal volumes of a modified incomplete Freund's adjuvant. These vaccines stimulated the production of neutralizing antibodies in mice and sheep, a cell mediated immune response in mice, and a protective immune response in sheep. The results suggest that gamma irradiation would be an effective means of inactivating BTV for the preparation of vaccines
Full Text Available Abstract Background The VP2 outer capsid protein Bluetongue Virus (BTV is responsible for receptor binding, haemagglutination and eliciting host-specific immunity. However, the assembly of this outer capsid protein on the transcriptionally active viral core would block transcription of the virus. Thus assembly of the outer capsid on the core particle must be a tightly controlled process during virus maturation. Earlier studies have detected mature virus particles associated with intermediate filaments in virus infected cells but the viral determinant for this association and the effect of disrupting intermediate filaments on virus assembly and release are unknown. Results In this study it is demonstrated that BTV VP2 associates with vimentin in both virus infected cells and in the absence of other viral proteins. Further, the determinants of vimentin localisation are mapped to the N-terminus of the protein and deletions of aminio acids between residues 65 and 114 are shown to disrupt VP2-vimentin association. Site directed mutation also reveals that amino acid residues Gly 70 and Val 72 are important in the VP2-vimentin association. Mutation of these amino acids resulted in a soluble VP2 capable of forming trimeric structures similar to unmodified protein that no longer associated with vimentin. Furthermore, pharmacological disruption of intermediate filaments, either directly or indirectly through the disruption of the microtubule network, inhibited virus release from BTV infected cells. Conclusion The principal findings of the research are that the association of mature BTV particles with intermediate filaments are driven by the interaction of VP2 with vimentin and that this interaction contributes to virus egress. Furthermore, i the N-terminal 118 amino acids of VP2 are sufficient to confer vimentin interaction. ii Deletion of amino acids 65–114 or mutation of amino acids 70–72 to DVD abrogates vimentin association. iii Finally
Bluetongue is caused by an arbovirus which produces widespread edema and tissue necrosis in domestic and wild ruminants that can be fatal. Bluetongue virus serotypes 10, 11, 13, and 17 are typically found throughout the United States (US), while serotype 2 was previously only detected in the southea...
The double-standed RNA gene coding for the surface antigen responsible for inducing neutralising anti-bodies has been isolated, converted to DNA, and cloned in the plasmid pBR322. So far, only plasmids containing inserts smaller than the gene have been obtained. The recombinant plasmids were isolated by screening for specific antibiotic resistance markers and characterized by size, restriction enzymes and hybridization with a 32P-labelled DNA probe made with BTV-m RNA as template. Possible strategies for the development of a bluetongue virus submit vaccine are discussed
Van der Saag, Matthew; Nicholas, Adrian; Ward, Michael; Kirkland, Peter
Biting midges from the genus Culicoides (Diptera: Ceratopogonidae) are the vectors of several globally important arboviruses that affect livestock. These include orbiviruses from the bluetongue virus (BTV) and African horse sickness virus (AHSV) groups and members of the Simbu serogroup of orthobunyaviruses, such as the recently emerged Schmallenberg virus. In this article, the authors evaluate several methods for feeding wild‑caught Australian Culicoides on BTV infected preparations of blood and sucrose. Feeding Culicoides on the membrane of embryonated chicken eggs was identified as the preferred feeding method. Although, cotton wool pads soaked in either virus‑infected blood or virus‑sucrose mixtures were also successful. A non‑destructive nucleic acid extraction technique for the detection of viral RNA in Culicoides was also evaluated as it allows for readily differentiating infected from non‑infected Culicoides. PMID:26741248
Patel, Avnish; Mohl, Bjorn-Patrick; Roy, Polly
The entry of viruses into host cells is one of the key processes of infection. The mechanisms of cellular entry for enveloped virus have been well studied. The fusion proteins as well as the facilitating cellular lipid factors involved in the viral fusion entry process have been well characterized. The process of non-enveloped virus cell entry, in comparison, remains poorly defined, particularly for large complex capsid viruses of the family Reoviridae, which comprises a range of mammalian pathogens. These viruses enter cells without the aid of a limiting membrane and thus cannot fuse with host cell membranes to enter cells. Instead, these viruses are believed to penetrate membranes of the host cell during endocytosis. However, the molecular mechanism of this process is largely undefined. Here we show, utilizing an in vitro liposome penetration assay and cell biology, that bluetongue virus (BTV), an archetypal member of the Reoviridae, utilizes the late endosome-specific lipid lysobisphosphatidic acid for productive membrane penetration and viral entry. Further, we provide preliminary evidence that lipid lysobisphosphatidic acid facilitates pore expansion during membrane penetration, suggesting a mechanism for lipid factor requirement of BTV. This finding indicates that despite the lack of a membrane envelope, the entry process of BTV is similar in specific lipid requirements to enveloped viruses that enter cells through the late endosome. These results are the first, to our knowledge, to demonstrate that a large non-enveloped virus of the Reoviridae has specific lipid requirements for membrane penetration and host cell entry. PMID:27036941
Full Text Available Abstract Bluetongue virus serotype 8 (BTV-8, which caused an epidemic in ruminants in central Western Europe in 2006 and 2007, seems to differ from other bluetongue serotypes in that it can spread transplacentally and has been associated with an increased incidence of abortion and other reproductive problems. For these reasons, and also because BTV-8 is threatening to spread to other parts of the world, there is a need for more information on the consequences of infection during pregnancy. The aim of the present study was to investigate whether hatched (i.e. zona pellucida-free in vitro produced bovine blastocysts at 8-9 days post insemination are susceptible to BTV-8 and whether such infection induces cell death as indicated by apoptosis. Exposure of hatched in vitro produced bovine blastocysts for 1 h to a medium containing 103.8 or 104.9 TCID50 of the virus resulted in active viral replication in between 25 and 100% of the cells at 72 h post exposure. The infected blastocysts also showed growth arrest as evidenced by lower total cell numbers and a significant level of cellular apoptosis. We conclude from this in vitro study that some of the reproductive problems that are reported when cattle herds are infected with BTV-8 may be attributed to direct infection of blastocysts and other early-stage embryos in utero.
Legisa, D; Gonzalez, F; De Stefano, G; Pereda, A; Dus Santos, M J
Bluetongue is an insect-transmitted viral disease of ruminant species, which represents a major barrier to the international trade of animals and their products. Bluetongue virus (BTV) has a genome composed of ten linear segments of dsRNA, which code for at least ten different viral proteins. In South America, serological evidence for the presence of BTV has been found in Peru, Argentina, Brazil, Ecuador and Chile. Brazil and Argentina are the only South American countries where BTV has been isolated. In Brazil, only one BTV isolate, serotype 12, has been reported, whereas in Argentina five BTV serotype 4 isolates have been obtained from cattle without clinical signs. Three of these five isolates were isolated during 1999-2001, whereas two of them were obtained as part of the present work. This study describes sequence comparisons and phylogenetic analyses of segment (Seg)-2, Seg-3, Seg-6, Seg-7 and Seg-10 of the first Argentinian field isolates of BTV. The analysis of Seg-2 and Seg-6 resulted in a single cluster of Argentinian sequences into the serotype 4 clade. In addition, the Argentinian sequences grouped within the nucleotype A clade, along with reference strains. The analysis of Seg-3, Seg-7 and Seg-10 showed that the Argentinian isolates grouped into the western topotype, indicating that the circulating virus had an African/European origin. Phylogenetic analysis revealed that the Argentinian sequences present a South American genetic identity, suggesting an independent lineage evolution. PMID:23152367
Full Text Available Abstract Even though bluetongue virus (BTV transmission is apparently interrupted during winter, bluetongue outbreaks often reappear in the next season (overwintering. Several mechanisms for BTV overwintering have been proposed, but to date, their relative importance remain unclear. In order to assess the probability of BTV overwintering by persistence in adult vectors, ruminants (through prolonged viraemia or a combination of both, a quantitative risk assessment model was developed. Furthermore, the model allowed the role played by the residual number of vectors present during winter to be examined, and the effect of a proportion of Culicoides living inside buildings (endophilic behaviour to be explored. The model was then applied to a real scenario: overwintering in Germany between 2006 and 2007. The results showed that the limited number of vectors active during winter seemed to allow the transmission of BTV during this period, and that while transmission was favoured by the endophilic behaviour of some Culicoides, its effect was limited. Even though transmission was possible, the likelihood of BTV overwintering by the mechanisms studied seemed too low to explain the observed re-emergence of the disease. Therefore, other overwintering mechanisms not considered in the model are likely to have played a significant role in BTV overwintering in Germany between 2006 and 2007.
Coetzee, Peter; van Vuuren, Moritz; Venter, Estelle H; Stokstad, Maria
Experimental infection studies with bluetongue virus (BTV) in the mammalian host have a history that stretches back to the late 18th century. Studies in a wide range of ruminant and camelid species as well as mice have been instrumental in understanding BTV transmission, bluetongue (BT) pathogenicity/pathogenesis, viral virulence, the induced immune response, as well as reproductive failures associated with BTV infection. These studies have in many cases been complemented by in vitro studies with BTV in different cell types in tissue culture. Together these studies have formed the basis for the understanding of BTV-host interaction and have contributed to the design of successful control strategies, including the development of effective vaccines. This review describes some of the fundamental and contemporary infection studies that have been conducted with BTV in the mammalian host and provides an overview of the principal animal welfare issues that should be considered when designing experimental infection studies with BTV in in vivo infection models. Examples are provided from the authors' own laboratory where the three Rs (replacement, reduction and refinement) have been implemented in the design of experimental infection studies with BTV in mice and goats. The use of the ARRIVE guidelines for the reporting of data from animal infection studies is emphasized. PMID:24462840
Feenstra, Femke; Drolet, B.S.; Boonstra, Jan; Rijn, van, C.J.M.
Background: Bluetongue virus (BTV) causes non-contagious haemorrhagic disease in ruminants and is transmitted by Culicoides spp. biting midges. BTV encodes four non-structural proteins of which NS3/NS3a is functional in virus release. NS3/NS3a is not essential for in vitro virus replication. However, deletion of NS3/NS3a leads to delayed virus release from mammalian cells and largely reduces virus release from insect cells. NS3/NS3a knockout BTV in sheep causes no viremia, but induces sterile...
Chand, Karam; Biswas, Sanchay K; Mondal, Bimalendu
An immuno-affinity chromatography technique for purification of infective bluetongue virus (BTV) has been descried using anti-core antibodies. BTV anti-core antibodies (prepared in guinea pig) were mixed with cell culture-grown BTV-1 and then the mixture was added to the cyanogens bromide-activated protein-A Sepharose column. Protein A binds to the antibody which in turn binds to the antigen (i.e. BTV). After thorough washing, antigen-antibody and antibody-protein A couplings were dissociated with 4M MgCl2, pH6.5. Antibody molecules were removed by dialysis and virus particles were concentrated by spin column ultrafiltration. Dialyzed and concentrated material was tested positive for BTV antigen by a sandwich ELISA and the infectivity of the chromatography-purified virus was demonstrated in cell culture. This method was applied for selective capture of BTV from a mixture of other viruses. As group-specific antibodies (against BTV core) were used to capture the virus, it is expected that virus of all BTV serotypes could be purified by this method. This method will be helpful for selective capture and enrichment of BTV from concurrently infected blood or tissue samples for efficient isolation in cell culture. Further, this method can be used for small scale purification of BTV avoiding ultracentrifugation. PMID:26925450
Ali Asghar Mozaffari; Mohammad Khalili; Sina Sabahi
Objective: To describe the seroprevalence rate of bluetongue virus (BTV) in goat flocks in southeast of Iran.Methods:93 sera samples were collected between 2011 and 2012. Antibodies to BTV in sera were detected by using a commercial competitive ELISA 3 according to manufacturer’s instructions. The blood samples were collected randomly from herds of southeast of Iran. A total of Results: The seroprevalence rates were 67.7% for goats. Within a herd, prevalence of BTV seropositive animals ranged from 33.3% to 100.0%. All goat flocks were positive to BTV antibodies.Conclusions:This study describes a high seroprevalence rate of BTV in goat flocks in southeast of Iran for the first time.
Estelle H. Venter
Full Text Available Bluetongue (BT, a disease that affects mainly sheep, causes economic losses owing to not only its deleterious effects on animals but also its associated impact on the restriction of movement of livestock and livestock germplasm. The causative agent, bluetongue virus (BTV, can occur in the semen of rams and bulls at the time of peak viraemia and be transferred to a developing foetus. The risk of the transmission of BTV by bovine embryos is negligible if the embryos are washed according to the International Embryo Transfer Society (IETS protocol. Two experiments were undertaken to determine whether this holds for ovine embryos that had been exposed to BTV. Firstly, the oestrus cycles of 12 ewes were synchronised and the 59 embryos that were obtained were exposed in vitro to BTV-2 and BTV-4 at a dilution of 1 x 102.88 and 1 x 103.5 respectively. In the second experiment, embryos were recovered from sheep at the peak of viraemia. A total of 96 embryos were collected from BTV-infected sheep 21 days after infection. In both experiments half the embryos were washed and treated with trypsin according to the IETS protocol while the remaining embryos were neither washed nor treated. All were tested for the presence of BTV using cell culture techniques. The virus was detected after three passages in BHK-21 cells only in one wash bath in the first experiment and two unwashed embryos exposed to BTV-4 at a titre of 1 x 103.5. No embryos or uterine flush fluids obtained from viraemic donors used in the second experiment were positive for BTV after the standard washing procedure had been followed. The washing procedure of the IETS protocol can thus clear sheep embryos infected with BTV either in vitro or in vivo.
Albertha R. van Zyl
Full Text Available Bluetongue virus (BTV causes severe disease in domestic and wild ruminants, and has recently caused several outbreaks in Europe. Current vaccines include live-attenuated and inactivated viruses; while these are effective, there is risk of reversion to virulence by mutation or reassortment with wild type viruses. Subunit or virus-like particle (VLP vaccines are safer options: VLP vaccines produced in insect cells by expression of the four BTV capsid proteins are protective against challenge; however, this is a costly production method. We investigated production of BTV VLPs in plants via Agrobacterium-mediated transient expression, an inexpensive production system very well suited to developing country use. Leaves infiltrated with recombinant pEAQ-HT vectors separately encoding the four BTV-8 capsid proteins produced more proteins than recombinant pTRA vectors. Plant expression using the pEAQ-HT vector resulted in both BTV-8 core-like particles (CLPs and VLPs; differentially controlling the concentration of infiltrated bacteria significantly influenced yield of the VLPs. In situ localisation of assembled particles was investigated by using transmission electron microscopy (TEM and it was shown that a mixed population of core-like particles (CLPs, consisting of VP3 and VP7 and VLPs were present as paracrystalline arrays in the cytoplasm of plant cells co-expressing all four capsid proteins.
Martinez-Torrecuadrada, J.L.; Langeveld, J.P.M.; Venteo, A.;
function of VP5, the other component of the capsid, is unknown. In this report, AHSV VP5, expressed in insect cells alone or together with VP2, was able to induce AHSV-specific neutralizing antibodies. Moreover, two VP5-specific monoclonal antibodies (MAbs) that were able to neutralize the virus in a....... Neutralizing epitopes were defined at positions 85-92 (PDPLSPGE) for MAb 10AE12 and at 179-185 (EEDLRTR) for MAb 10AC6. Epitope 10AE12 is highly conserved between the different orbiviruses. MAb 10AE12 was able to recognize bluetongue virus VP5 and epizootic hemorrhagic disease virus VP5 by several techniques...
Kumar, Lalit; Batra, Kanisht; Chaudhary, Deepika; Gupta, Akhil Kumar; Dalal, Anita; Kalyanaraman, Brindha; Irulappan, Ganesan P.; Kumar, Vinay
The complete genome sequence of a reassortant field strain (IND2014/01) of Bluetongue virus (BTV) serotype 16, isolated from sheep from southern India in 2014, was sequenced. The total genome size was 19,186 bp. Sequence comparisons of all genome segments, except segment 5 (Seg-5), showed that IND2014/01 belonged to the major eastern topotype of BTV. PMID:27540057
Bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV) are arthropod-borne viruses of significant animal agriculture importance. Clinical disease caused by BTV is most commonly observed in sheep and some wild ruminants; however, the recent outbreak in European Union has resulted in se...
Full Text Available Genetic exchange by a process of genome-segment 'reassortment' represents an important mechanism for evolutionary change in all viruses with segmented genomes, yet in many cases a detailed understanding of its frequency and biological consequences is lacking. We provide a comprehensive assessment of reassortment in bluetongue virus (BTV, a globally important insect-borne pathogen of livestock, during recent outbreaks in Europe. Full-genome sequences were generated and analysed for over 150 isolates belonging to the different BTV serotypes that have emerged in the region over the last 5 decades. Based on this novel dataset we confirm that reassortment is a frequent process that plays an important and on-going role in evolution of the virus. We found evidence for reassortment in all ten segments without a significant bias towards any particular segment. However, we observed biases in the relative frequency at which particular segments were associated with each other during reassortment. This points to selective constraints possibly caused by functional relationships between individual proteins or genome segments and genome-wide epistatic interactions. Sites under positive selection were more likely to undergo amino acid changes in newly reassorted viruses, providing additional evidence for adaptive dynamics as a consequence of reassortment. We show that the live attenuated vaccines recently used in Europe have repeatedly reassorted with field strains, contributing to their genotypic, and potentially phenotypic, variability. The high degree of plasticity seen in the BTV genome in terms of segment origin suggests that current classification schemes that are based primarily on serotype, which is determined by only a single genome segment, are inadequate. Our work highlights the need for a better understanding of the mechanisms and epidemiological consequences of reassortment in BTV, as well as other segmented RNA viruses.
Mirjam T W van der Sluijs
Full Text Available The Bluetongue virus serotype 8 (BTV-8 strain, which emerged in Europe in 2006, had an unusually high ability to cause foetal infection in pregnant ruminants. Other serotypes of BTV had already been present in Europe for more than a decade, but transplacental transmission of these strains had never been demonstrated. To determine whether transplacental transmission is a unique feature of BTV-8 we compared the incidence and pathological consequences of transplacental transmission of BTV-8 to that of BTV-1. Nine pregnant ewes were infected with either BTV-8 or BTV-1. The BTV strains used for the infection were field strains isolated on embryonated chicken eggs and passaged twice on mammalian cells. Blood samples were taken to monitor the viraemia in the ewes. Four weeks after the infection, the foetuses were examined for pathological changes and for the presence of BTV. BTV-8 could be demonstrated in 12 foetuses (43% from 5 ewes (56%. %. BTV-1 was detected in 14 foetuses (82% from 6 ewes (67%. Pathological changes were mainly found in the central nervous system. In the BTV-8 group, lympho-histiocytic infiltrates, gliosis and slight vacuolation of the neuropil were found. BTV-1 infection induced a severe necrotizing encephalopathy and severe meningitis, with macroscopic hydranencephaly or porencephaly in 8 foetuses. In our experimental setting, using low passaged virus strains, BTV-1 was able to induce transplacental transmission to a higher incidence compared to BTV-8, causing more severe pathology.
Full Text Available Bluetongue virus (BTV belongs to the genus Orbivirus within the family Reoviridae. The development of vector-based vaccines expressing conserved protective antigens results in increased immune activation and could reduce the number of multiserotype vaccinations required, therefore providing a cost-effective product. Recent recombinant DNA technology has allowed the development of novel strategies to develop marker and safe vaccines against BTV. We have now engineered naked DNAs and recombinant modified vaccinia virus Ankara (rMVA expressing VP2, VP7 and NS1 proteins from BTV-4. IFNAR((-/- mice inoculated with DNA/rMVA-VP2,-VP7-NS1 in an heterologous prime boost vaccination strategy generated significant levels of antibodies specific of VP2, VP7, and NS1, including those with neutralizing activity against BTV-4. In addition, vaccination stimulated specific CD8(+ T cell responses against these three BTV proteins. Importantly, the vaccine combination expressing NS1, VP2 and VP7 proteins of BTV-4, elicited sterile protection against a lethal dose of homologous BTV-4 infection. Remarkably, the vaccine induced cross-protection against lethal doses of heterologous BTV-8 and BTV-1 suggesting that the DNA/rMVA-VP2,-VP7,-NS1 marker vaccine is a promising multiserotype vaccine against BTV.
Full Text Available The aim of this study was to assess the mechanisms of transmission of bluetongue virus serotype 26 (BTV-26 in goats. A previous study, which investigated the pathogenicity and infection kinetics of BTV-26 in goats, unexpectedly revealed that one control goat may have been infected through a direct contact transmission route. To investigate the transmission mechanisms of BTV-26 in more detail an experimental infection study was carried out in which three goats were infected with BTV-26, three goats were kept uninfected, but were housed in direct contact with the infected goats, and an additional four goats were kept in indirect contact separated from infected goats by metal gates. This barrier allowed the goats to have occasional face-to-face contact in the same airspace, but feeding, watering, sampling and environmental cleaning was carried out separately. The three experimentally infected goats did not show clinical signs of BTV, however high levels of viral RNA were detected and virus was isolated from their blood. At 21 dpi viral RNA was detected in, and virus was isolated from the blood of the three direct contact goats, which also seroconverted. The four indirect barrier contact goats remained uninfected throughout the duration of the experiment. In order to assess replication in a laboratory model species of Culicoides biting midge, more than 300 Culicoides sonorensis were fed a BTV-26 spiked blood meal and incubated for 7 days. The dissemination of BTV-26 in individual C. sonorensis was inferred from the quantity of virus RNA and indicated that none of the insects processed at day 7 possessed transmissible infections. This study shows that BTV-26 is easily transmitted through direct contact transmission between goats, and the strain does not seem to replicate in C. sonorensis midges using standard incubation conditions.
Maan, Narender S.; Belaganahalli, Manjunatha N.; Kumar, Aman; Batra, Kanisht; Rao, Pavuluri Panduranga; Hemadri, Divakar; Reddy, Yella Narasimha; Putty, Kalyani; Krishnajyothi, Yadlapati; Reddy, G. Hanmanth; Singh, Karam Pal; Hegde, Nagendra R.; Nomikou, Kyriaki; Sreenivasulu, Daggupati
Southern Indian isolate IND1994/01 of bluetongue virus serotype 2 (BTV-2), from the Orbivirus Reference Collection at the Pirbright Institute (http://www.reoviridae.org/dsRNA_virus_proteins/ReoID/btv-2.htm#IND1994/01), was sequenced. Its genome segment 6 (Seg-6) [encoding VP5(OCP2)] is identical to that of the Indian BTV-1 isolate (IND2003/05), while Seg-5 and Seg-9 are closely related to isolates from South Africa and the United States, respectively. PMID:25858823
Abdallah M Samy
Full Text Available The geographic distribution of arboviruses has received considerable attention after several dramatic emergence events around the world. Bluetongue virus (BTV is classified among category "A" diseases notifiable to the World Organization of Animal Health (OIE, and is transmitted among ruminants by biting midges of the genus Culicoides. Here, we developed a comprehensive occurrence data set to map the current distribution, estimate the ecological niche, and explore the future potential distribution of BTV globally using ecological niche modeling and based on diverse future climate scenarios from general circulation models (GCMs for four representative concentration pathways (RCPs. The broad ecological niche and potential geographic distribution of BTV under present-day conditions reflected the disease's current distribution across the world in tropical, subtropical, and temperate regions. All model predictions were significantly better than random expectations. As a further evaluation of model robustness, we compared our model predictions to 331 independent records from most recent outbreaks from the Food and Agriculture Organization Emergency Prevention System for Transboundary Animal and Plant Pests and Diseases Information System (EMPRES-i; all were successfully anticipated by the BTV model. Finally, we tested ecological niche similarity among possible vectors and BTV, and could not reject hypotheses of niche similarity. Under future-climate conditions, the potential distribution of BTV was predicted to broaden, especially in central Africa, United States, and western Russia.
Xu, Q Y; Sun, E C; Feng, Y F; Li, J P; Lv, S; Zhang, Q; Wang, H X; Zhang, J K; Wu, D L
Bluetongue (BT), which is caused by the BT virus (BTV), is an important disease in ruminants that leads to significant economic losses in the husbandry industry. To detect BTV-specific antibodies in serum, a protein chip detection method based on a novel solid supporting material known as polymer-coated initiator-integrated poly (dimethyl siloxane) (iPDMS) was developed. With a threshold of 25% (signal-to-noise percentage), the sensitivity and specificity of the protein chip were 98.6% and 94.8%, respectively. Furthermore, spot serum samples obtained from six provinces of China were tested with the protein chip and a commercially available BTV enzyme-linked immunosorbent assay (ELISA) kit (IDEXX). Of 615 samples, BTV-specific antibodies were detected in 200 (32.52%) by the protein chip and in 176 (28.62%) by the IDEXX BTV ELISA kit. Comparison of the protein chip with the commercial IDEXX BTV ELISA kit yielded the following spot serum detection results: a total coincidence, a negative coincidence and a positive coincidence of 95.12%, 99.28% and 86.5%, respectively. With the protein chip, the BTV-specific serum antibody was detected in samples from all six provinces, and the positive rates ranged from 4.12 to 74.4%. These results indicate that this protein chip detection method based on iPDMS is useful for the serological diagnosis of BTV infection and for epidemiological investigation. PMID:27063641
Samy, Abdallah M; Peterson, A Townsend
The geographic distribution of arboviruses has received considerable attention after several dramatic emergence events around the world. Bluetongue virus (BTV) is classified among category "A" diseases notifiable to the World Organization of Animal Health (OIE), and is transmitted among ruminants by biting midges of the genus Culicoides. Here, we developed a comprehensive occurrence data set to map the current distribution, estimate the ecological niche, and explore the future potential distribution of BTV globally using ecological niche modeling and based on diverse future climate scenarios from general circulation models (GCMs) for four representative concentration pathways (RCPs). The broad ecological niche and potential geographic distribution of BTV under present-day conditions reflected the disease's current distribution across the world in tropical, subtropical, and temperate regions. All model predictions were significantly better than random expectations. As a further evaluation of model robustness, we compared our model predictions to 331 independent records from most recent outbreaks from the Food and Agriculture Organization Emergency Prevention System for Transboundary Animal and Plant Pests and Diseases Information System (EMPRES-i); all were successfully anticipated by the BTV model. Finally, we tested ecological niche similarity among possible vectors and BTV, and could not reject hypotheses of niche similarity. Under future-climate conditions, the potential distribution of BTV was predicted to broaden, especially in central Africa, United States, and western Russia. PMID:26959424
Samy, Abdallah M.; Peterson, A. Townsend
The geographic distribution of arboviruses has received considerable attention after several dramatic emergence events around the world. Bluetongue virus (BTV) is classified among category “A” diseases notifiable to the World Organization of Animal Health (OIE), and is transmitted among ruminants by biting midges of the genus Culicoides. Here, we developed a comprehensive occurrence data set to map the current distribution, estimate the ecological niche, and explore the future potential distribution of BTV globally using ecological niche modeling and based on diverse future climate scenarios from general circulation models (GCMs) for four representative concentration pathways (RCPs). The broad ecological niche and potential geographic distribution of BTV under present-day conditions reflected the disease’s current distribution across the world in tropical, subtropical, and temperate regions. All model predictions were significantly better than random expectations. As a further evaluation of model robustness, we compared our model predictions to 331 independent records from most recent outbreaks from the Food and Agriculture Organization Emergency Prevention System for Transboundary Animal and Plant Pests and Diseases Information System (EMPRES-i); all were successfully anticipated by the BTV model. Finally, we tested ecological niche similarity among possible vectors and BTV, and could not reject hypotheses of niche similarity. Under future-climate conditions, the potential distribution of BTV was predicted to broaden, especially in central Africa, United States, and western Russia. PMID:26959424
Hui-qiong YIN; Gai-ping ZHANG; Hong ZHANG; Jin-gang ZHANG
Twenty five serotypes of Bluetongue virus (BTV) have been identified worldwide. Rapid and reliable methods of virus universal detection are essential for fighting against bluetongue (BT). We have therefore developed and evaluated a pair of primers which can detect various serotypes of BTV by RT-PCR. Analysis of the viral protein 7 (VP7) and the non-structural protein (NS1) gene from different serotypes of BTV by DNAstar showed that the 5' end of the NS1 gene is the most conserved region. The primer pairs (P1 and P2) were designed based on the highly conserved region of NS1. The novel primers were evaluated by detecting BTV serotypes 1, 3, 5, 8, 10, 11, 21 and 22. The specificity of the primers was estimated by comparing to gene sequences of viruses published in GenBank, and further assessed by detecting BTV serotype 1-12 and Epizootic hemorrhagic disease virus (EHDV) serotype 1-4. The sensitivity and repeatability of PCR with the novel primers were evaluated by successfully detecting the recombinant plasmid pGEM-T121 containing the diagnosed nucleotide sequence. Our results suggest that these unique primers can be used in high throughout and universal detection of the NS1 gene from various BTV serotypes.
de Koeijer Aline A
Full Text Available Abstract The recent bluetongue virus serotype 8 (BTV-8 epidemic in Western Europe struck hard. Controlling the infection was difficult and a good and safe vaccine was not available until the spring of 2008. Little was known regarding BTV transmission in Western Europe or the efficacy of control measures. Quantitative details on transmission are essential to assess the potential and efficacy of such measures. To quantify virus transmission between herds, a temporal and a spatio-temporal analysis were applied to data on reported infected herds in 2006. We calculated the basic reproduction number between herds (Rh: expected number of new infections, generated by one initial infected herd in a susceptible environment. It was found to be of the same order of magnitude as that of an infection with Foot and Mouth Disease (FMD in The Netherlands, e.g. around 4. We concluded that an average day temperature of at least 15°C is required for BTV-8 transmission between herds in Western Europe. A few degrees increase in temperature is found to lead to a major increase in BTV-8 transmission. We also found that the applied disease control (spatial zones based on 20 km radius restricting animal transport to outside regions led to a spatial transmission pattern of BTV-8, with 85% of transmission restricted to a 20 km range. This 20 km equals the scale of the protection zones. We concluded that free animal movement led to substantial faster spread of the BTV-8 epidemic over space as compared to a situation with animal movement restrictions.
Chand, Karam; Biswas, Sanchay Kumar; Sharma, Gaurav; Saxena, Arpit; Tewari, Neha; Mahajan, Sonalika; Pandey, Awadh Bihari
This communication reports full genome sequencing of the bluetongue virus-1 (BTV-1) isolate MKD20/08/Ind from goat in northern India. The total BTV-1 genome size was found to be 19,190bp. A comparison study between the Indian isolate and other global isolates revealed that it belongs to the 'Eastern' BTV topotype. The full genome sequence of BTV-1 will provide vital information on its geographical origin and it will also be proved useful for comparing the Indian isolate with global isolates from other host species. PMID:27266632
De Leeuw, I; Garigliany, M; Bertels, G; Willems, T; Desmecht, D; De Clercq, K
Bluetongue virus serotype 8 (BTV-8) was responsible for a large outbreak among European ruminant populations in 2006-2009. In spring 2008, a massive vaccination campaign was undertaken, leading to the progressive disappearance of the virus. During surveillance programmes in Western Europe in 2010-2011, a low but significant number of animals were found weakly positive using BTV-specific real-time RT-PCR, raising questions about a possible low level of virus circulation. An interference of the BTV-8 inactivated vaccine on the result of the real-time RT-PCR was also hypothesized. Several studies specifically addressed the potential association between a recent vaccination and BTV-8 RNA detection in the blood of sheep. Results were contradictory and cattles were not investigated. To enlighten this point, a large study was performed to determine the risks of detection of bluetongue vaccine-associated RNA in the blood and spleen of cattle using real-time RT-PCR. Overall, the results presented clearly demonstrate that vaccine viral RNA can reach the blood circulation in sufficient amounts to be detected by real-time RT-PCR in cattle. This BTV-8 vaccine RNA carriage appears as short lasting. PMID:23611408
Drolet, Barbara S.; Reister-Hendricks, Lindsey M.; Podell, Brendan K.; Breitenbach, Jonathan E.; Mcvey, D.S.; Rijn, van Piet A.; Bowen, Richard A.
Bluetongue virus (BTV) is an orbivirus transmitted by biting midges (Culicoides spp.) that can result in moderate to high morbidity and mortality primarily in sheep and white-tailed deer. Although only 5 serotypes of BTV are considered endemic to the United States, as many as 11 incursive serotyp
Annet G J Velthuis
Full Text Available BACKGROUND: Bluetongue (BT is a vector-borne disease of ruminants caused by bluetongue virus that is transmitted by biting midges (Culicoides spp.. In 2006, the introduction of BTV serotype 8 (BTV-8 caused a severe epidemic in Western and Central Europe. The principal effective veterinary measure in response to BT was believed to be vaccination accompanied by other measures such as movement restrictions and surveillance. As the number of vaccine doses available at the start of the vaccination campaign was rather uncertain, the Dutch Ministry of Agriculture, Nature and Food Quality and the Dutch agricultural industry wanted to evaluate several different vaccination strategies. This study aimed to rank eight vaccination strategies based on their efficiency (i.e. net costs in relation to prevented losses or benefits for controlling the bluetongue virus serotype 8 epidemic in 2008. METHODOLOGY/PRINCIPAL FINDINGS: An economic model was developed that included the Dutch professional cattle, sheep and goat sectors together with the hobby farms. Strategies were evaluated based on the least cost - highest benefit frontier, the benefit-cost ratio and the total net returns. Strategy F, where all adult sheep at professional farms in The Netherlands would be vaccinated was very efficient at lowest costs, whereas strategy D, where additional to all adult sheep at professional farms also all adult cattle in the four Northern provinces would be vaccinated, was also very efficient but at a little higher costs. Strategy C, where all adult sheep and cattle at professional farms in the whole of The Netherlands would be vaccinated was also efficient but again at higher costs. CONCLUSIONS/SIGNIFICANCE: This study demonstrates that a financial analysis differentiates between vaccination strategies and indicates important decision rules based on efficiency.
Full Text Available Since 1998 there have been significant changes in the global distribution of bluetongue virus (BTV. Ten previously exotic BTV serotypes have been detected in Europe, causing severe disease outbreaks in naïve ruminant populations. Previously exotic BTV serotypes were also identified in the USA, Israel, Australia and India. BTV is transmitted by biting midges (Culicoides spp. and changes in the distribution of vector species, climate change, increased international travel and trade are thought to have contributed to these events. Thirteen BTV serotypes have been isolated in India since first reports of the disease in the country during 1964. Efficient methods for preparation of viral dsRNA and cDNA synthesis, have facilitated full-genome sequencing of BTV strains from the region. These studies introduce a new approach for BTV characterization, based on full-genome sequencing and phylogenetic analyses, facilitating the identification of BTV serotype, topotype and reassortant strains. Phylogenetic analyses show that most of the equivalent genome-segments of Indian BTV strains are closely related, clustering within a major eastern BTV 'topotype'. However, genome-segment 5 (Seg-5 encoding NS1, from multiple post 1982 Indian isolates, originated from a western BTV topotype. All ten genome-segments of BTV-2 isolates (IND2003/01, IND2003/02 and IND2003/03 are closely related (>99% identity to a South African BTV-2 vaccine-strain (western topotype. Similarly BTV-10 isolates (IND2003/06; IND2005/04 show >99% identity in all genome segments, to the prototype BTV-10 (CA-8 strain from the USA. These data suggest repeated introductions of western BTV field and/or vaccine-strains into India, potentially linked to animal or vector-insect movements, or unauthorised use of 'live' South African or American BTV-vaccines in the country. The data presented will help improve nucleic acid based diagnostics for Indian serotypes/topotypes, as part of control strategies.
Full Text Available Aim: The objective of this study was conducted to determine the seroprevalence and S7 gene characterization of BTV of sheep in the West of Iran, during 2007-2008. Materials and Methods: A total 372 sheep blood samples were collected from known seropositive regions in the West of Iran. Anti-BTV antibodies were detected in the serum samples by group specific, c-ELISA. Extractions of the dsRNA from whole blood samples were carried out. The One-step RT-PCR kit was used for the detection of S7 BTV gene in the blood samples. PCR products of the first amplification (RT-PCR were used; template in the nested PCR. Products were separated by 1.2% Agarose gel electrophoresis. Nested PCR products of S7 segment from positive samples and the reference strain; BTV1 (RSA vvvv/01 were prepared for sequencing. All sequences were subjected to multiple sequence alignments and phylogenetic analysis. Results: The results showed widespread presence of the anti-BTV antibodies in the province's sheep population, where 46.77% of the tested sera were positive on ELISA. Bluetongue viruses were diagnosed in some animals by RT-PCR and nested PCR, by targeting S7 segment. This genome segment was sequenced and analyzed in four samples as a conserved gene in BTV serogroup. This group was very similar to the West BTV strains from US, Africa and Europe. This clustered was categorized with BTV4 from Turkey. Conclusion: Increases in epidemic disease may constitute a serious problem for Iran's rural economy in future, and the situation is likely to worsen in the next few years as the proportion of unvaccinated livestock increases. [Vet World 2012; 5(9.000: 549-555
Full text: Arthropod-borne animal viruses (arboviruses) cause significant livestock and economic losses to world agriculture. This paper discusses the current and potential impact of these viruses, as well as the current and developing molecular diagnostic tools for these emerging and re-emerging insect transmitted viruses affecting livestock and wildlife. The emphasis will be on those viruses which there have been significant recent outbreaks in livestock including bluetongue virus (BTV), epizootic hemorrhagic disease virus (EHDV), vesicular stomatitis virus (VSV), and Rift Valley fever virus (RVFV). The current readiness for rapid detection of arboviruses is fairly high, but there is a need for global harmonization and continued evaluation due to the genetic variation of these unique pathogens. The tool chest for molecular detection contains a range of assays from low technology to high-throughput sophisticated devices. Biting midges in the genus Culicoides transmit arboviruses affecting livestock, including BTV and EHDV. These viruses cause sub-acute to lethal disease cattle, sheep, goats and/or wild ungulates resulting in worldwide losses attributed to BTV alone estimated at $3 billion annually. There was a fairly good understanding of the epidemiology of BTV until recent introduction of BTV into Europe. Of particular concern is the economic and unique disease impact BTV-8 has had on Europe and the fact that there have been multiple isolations of exotic BTV serotypes in the U.S. over the past 3 years. In Europe, killed BTV-8 vaccines are being utilized to control and potential eradicate the disease. In the U.S., there is only one commercial vaccine available nation-wide, and it is specific to BTV type 10. There is limited or no cross protection between serotypes thus complicates the control of the disease. The related orbivirus, EHDV, is of considerable interest to the captive cervid industry, and EHDV serotype 7 has been associated with clinical disease in
Græsbøll, Kaare; Bødker, Rene; Enøe, Claes; Christiansen, Lasse Engbo
Bluetongue is a disease of ruminants which reached Denmark in 2007. We present a process-based stochastic simulation model of vector-borne diseases, where host animals are not confined to a central geographic farm coordinate, but can be distributed onto pasture areas. Furthermore vectors fly free...
Græsbøll, Kaare; Bødker, Rene; Enøe, Claes; Christiansen, Lasse Engbo
of such changes are: vaccinations, acquired immunity, vector density and control, meteorological variations, wind pattern, and so on. Including more and more variables leads to a more process oriented model. A full process oriented approach simulates the movement of virus between vectors and host......, describing density and motion of vectors/hosts, climatic variables, and so on will theoretically be able to describe an outbreak under any circumstances. It will most likely contain parameters not very well established, and is also very heavy in computer time. Nevertheless, we have tried to create a...... relatively detailed simulation spread model. And by using empirical spread kernels from past outbreaks we have fitted some of the more uncertain parameters for this case study. A stochastic simulation model was developed for the spread of bluetongue virus. In the model hosts (cattle) and vectors (Culicoides...
Maan, Sushila; Maan, Narender S.; Belaganahalli, Manjunatha N.; Rao, Pavuluri Panduranga; Singh, Karam Pal; Hemadri, Divakar; Putty, Kalyani; Kumar, Aman; Batra, Kanisht; Krishnajyothi, Yadlapati; Chandel, Bharat S.; Reddy, G. Hanmanth; Nomikou, Kyriaki; Reddy, Yella Narasimha; Attoui, Houssam; Hegde, Nagendra R.; Mertens, Peter P. C.
Since 1998 there have been significant changes in the global distribution of bluetongue virus (BTV). Ten previously exotic BTV serotypes have been detected in Europe, causing severe disease outbreaks in naïve ruminant populations. Previously exotic BTV serotypes were also identified in the USA, Israel, Australia and India. BTV is transmitted by biting midges (Culicoides spp.) and changes in the distribution of vector species, climate change, increased international travel and trade are thought to have contributed to these events. Thirteen BTV serotypes have been isolated in India since first reports of the disease in the country during 1964. Efficient methods for preparation of viral dsRNA and cDNA synthesis, have facilitated full-genome sequencing of BTV strains from the region. These studies introduce a new approach for BTV characterization, based on full-genome sequencing and phylogenetic analyses, facilitating the identification of BTV serotype, topotype and reassortant strains. Phylogenetic analyses show that most of the equivalent genome-segments of Indian BTV strains are closely related, clustering within a major eastern BTV ‘topotype’. However, genome-segment 5 (Seg-5) encoding NS1, from multiple post 1982 Indian isolates, originated from a western BTV topotype. All ten genome-segments of BTV-2 isolates (IND2003/01, IND2003/02 and IND2003/03) are closely related (>99% identity) to a South African BTV-2 vaccine-strain (western topotype). Similarly BTV-10 isolates (IND2003/06; IND2005/04) show >99% identity in all genome segments, to the prototype BTV-10 (CA-8) strain from the USA. These data suggest repeated introductions of western BTV field and/or vaccine-strains into India, potentially linked to animal or vector-insect movements, or unauthorised use of ‘live’ South African or American BTV-vaccines in the country. The data presented will help improve nucleic acid based diagnostics for Indian serotypes/topotypes, as part of control strategies. PMID
Full Text Available Bluetongue is a viral, infectious, non-contiguous, vector transmitted disease of ruminants animals, caused by an Orbivurus. Despite the disease is not zoonoses, it is with high economic importance and as other OIE listed disease, significantly interfere with animal health and trade. Clinically, most affected species are sheep, however cattle serve as reservoir of infection and play major role on epidemiology of disease. Presence of Blue tongue disease proved only when it is based on laboratory tests.
Full Text Available In mid September 2008, clinical signs of bluetongue (particularly coronitis were observed in cows on three different farms in eastern Netherlands (Luttenberg, Heeten, and Barchem, two of which had been vaccinated with an inactivated BTV-8 vaccine (during May-June 2008. Bluetongue virus (BTV infection was also detected on a fourth farm (Oldenzaal in the same area while testing for export. BTV RNA was subsequently identified by real time RT-PCR targeting genome-segment (Seg- 10, in blood samples from each farm. The virus was isolated from the Heeten sample (IAH "dsRNA virus reference collection" [dsRNA-VRC] isolate number NET2008/05 and typed as BTV-6 by RT-PCR targeting Seg-2. Sequencing confirmed the virus type, showing an identical Seg-2 sequence to that of the South African BTV-6 live-vaccine-strain. Although most of the other genome segments also showed very high levels of identity to the BTV-6 vaccine (99.7 to 100%, Seg-10 showed greatest identity (98.4% to the BTV-2 vaccine (RSAvvv2/02, indicating that NET2008/05 had acquired a different Seg-10 by reassortment. Although Seg-7 from NET2008/05 was also most closely related to the BTV-6 vaccine (99.7/100% nt/aa identity, the Seg-7 sequence derived from the blood sample of the same animal (NET2008/06 was identical to that of the Netherlands BTV-8 (NET2006/04 and NET2007/01. This indicates that the blood contained two different Seg-7 sequences, one of which (from the BTV-6 vaccine was selected during virus isolation in cell-culture. The predominance of the BTV-8 Seg-7 in the blood sample suggests that the virus was in the process of reassorting with the northern field strain of BTV-8. Two genome segments of the virus showed significant differences from the BTV-6 vaccine, indicating that they had been acquired by reassortment event with BTV-8, and another unknown parental-strain. However, the route by which BTV-6 and BTV-8 entered northern Europe was not established.
Bluetongue is a disease of sheep, but cattle are the principal vertebrate reservoirs of the virus. Once established, "it is impossible to actively eradicate bluetongue virus". The virus will circulate, generally subclinically, in cattle and other ruminants, and in midges. The objective of this study was to examine the correlation between the bluetongue incidence data(2006) and the mortality data(2006). To achieve the main objective of this report, the difference in the 2006 mortality and mean...
Boyle, David B; Bulach, Dieter M; Amos-Ritchie, Rachel; Adams, Mathew M; Walker, Peter J; Weir, Richard
Bluetongue virus (BTV) is transmitted by biting midges (Culicoides spp.). It causes disease mainly in sheep and occasionally in cattle and other species. BTV has spread into northern Europe, causing disease in sheep and cattle. The introduction of new serotypes, changes in vector species, and climate change have contributed to these changes. Ten BTV serotypes have been isolated in Australia without apparent associated disease. Simplified methods for preferential isolation of double-stranded RNA (dsRNA) and template preparation enabled high-throughput sequencing of the 10 genome segments of all Australian BTV prototype serotypes. Phylogenetic analysis reinforced the Western and Eastern topotypes previously characterized but revealed unique features of several Australian BTVs. Many of the Australian BTV genome segments (Seg-) were closely related, clustering together within the Eastern topotypes. A novel Australian topotype for Seg-5 (NS1) was identified, with taxa spread across several serotypes and over time. Seg-1, -2, -3, -4, -6, -7, -9, and -10 of BTV_2_AUS_2008 were most closely related to the cognate segments of viruses from Taiwan and Asia and not other Australian viruses, supporting the conclusion that BTV_2 entered Australia recently. The Australian BTV_15_AUS_1982 prototype was revealed to be unusual among the Australian BTV isolates, with Seg-3 and -8 distantly related to other BTV sequences from all serotypes. PMID:22514341
Matsuo, Eiko [Microbiology and Immunology, Division of Animal Science, Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, 1-1, Rokkodai, Nada-ku, Kobe-City 657-8501 (Japan); Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT (United Kingdom); Leon, Esther; Matthews, Steve J. [Division of Molecular Biosciences, Centre for Structural Biology, Imperial College London, South Kensington, London SW7 2AZ (United Kingdom); Roy, Polly, E-mail: email@example.com [Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT (United Kingdom)
Highlights: • NMR analysis on BTV VP6 reveals two large loop regions. • The loss of a loop (aa 34–130) does not affect the overall fold of the protein. • A region of VP6 (aa 34–92) is not required for BTV replication. • A region of VP6 (aa 93–130) plays an essential role in the virus replication. - Abstract: Bluetongue virus core protein VP6 is an ATP hydrolysis dependent RNA helicase. However, despite much study, the precise role of VP6 within the viral capsid and its structure remain unclear. To investigate the requirement of VP6 in BTV replication, we initiated a structural and biological study. Multinuclear nuclear magnetic resonance spectra were assigned on his-tagged full-length VP6 (329 amino acid residues) as well as several truncated VP6 variants. The analysis revealed a large structured domain with two large loop regions that exhibit significant conformational exchange. One of the loops (amino acid position 34–130) could be removed without affecting the overall fold of the protein. Moreover, using a BTV reverse genetics system, it was possible to demonstrate that the VP6-truncated BTV was viable in BHK cells in the absence of any helper VP6 protein, suggesting that a large portion of this loop region is not absolutely required for BTV replication.
Highlights: • NMR analysis on BTV VP6 reveals two large loop regions. • The loss of a loop (aa 34–130) does not affect the overall fold of the protein. • A region of VP6 (aa 34–92) is not required for BTV replication. • A region of VP6 (aa 93–130) plays an essential role in the virus replication. - Abstract: Bluetongue virus core protein VP6 is an ATP hydrolysis dependent RNA helicase. However, despite much study, the precise role of VP6 within the viral capsid and its structure remain unclear. To investigate the requirement of VP6 in BTV replication, we initiated a structural and biological study. Multinuclear nuclear magnetic resonance spectra were assigned on his-tagged full-length VP6 (329 amino acid residues) as well as several truncated VP6 variants. The analysis revealed a large structured domain with two large loop regions that exhibit significant conformational exchange. One of the loops (amino acid position 34–130) could be removed without affecting the overall fold of the protein. Moreover, using a BTV reverse genetics system, it was possible to demonstrate that the VP6-truncated BTV was viable in BHK cells in the absence of any helper VP6 protein, suggesting that a large portion of this loop region is not absolutely required for BTV replication
Boyce, M; McCrae, M A
The regulatory elements which control the processes of virus replication and gene expression in the Orbivirus genus are uncharacterized in terms of both their locations within genome segments and their specific functions. The reverse genetics system for the type species, Bluetongue virus, has been used in combination with RNA secondary structure prediction to identify and map the positions of cis-acting regions within genome segment 10. Through the simultaneous introduction of variability at multiple nucleotide positions in the rescue RNA population, the functional contribution of these positions was used to map regions containing cis-acting elements essential for virus viability. Nucleotides that were individually lethal when varied mapped within a region of predicted secondary structure involving base pairing between the 5' and 3' ends of the transcript. An extended region of predicted perfect base pairing located within the 3' untranslated region of the genome segment was also found to be required for virus viability. In contrast to the identification of individually lethal mutations, gross alteration of the composition of this predicted stem region was possible, providing the base-pairing potential between the two strands was maintained, identifying a structural feature predicted to be conserved throughout the Orbivirus genus. The approach of identifying cis-acting sequences through sequencing the recovered virus following the rescue of a degenerate RNA population is broadly applicable to viruses where reverse genetics is available. PMID:26248463
Shaswati Subhadarsini Pany
Full Text Available Aim: The aim of the present study was to carry out antigenic detection of bluetongue virus (BTV among the small ruminant population of two different geographical regions of Odisha (coastal and central using recombinant VP7 (r-VP-7 based sandwich enzyme-linked immunosorbent assay (s-ELISA. Materials and Methods: Blood samples (n=274 were collected from two different geographical pockets of Odisha, which covered mostly the coastal and central regions. Of the total samples under study 185 were from goat and 89 were from sheep. The blood samples were tested for the presence of BTV antigen by r-VP7 based s-ELISA. Results: r-VP-7 s-ELISA detected BTV antigen in 52.43% and 44.94% of the goat and sheep population under study, respectively. This study highlights the antigenic persistence of BTV in the state for the 1st time. Conclusion: This high antigenic presence in both sheep and goat population suggests an alarming BTV infection in field conditions which warrants more systematic study directed toward isolation and characterization studies as well as the implementation of control strategy for BT in Odisha.
Feenstra, Femke; Maris-Veldhuis, Mieke; Daus, Franz J; Tacken, Mirriam G J; Moormann, Rob J M; van Gennip, René G P; van Rijn, Piet A
Bluetongue virus (BTV) causes Bluetongue in ruminants and is transmitted by Culicoides biting midges. Vaccination is the most effective measure to control vector borne diseases; however, there are 26 known BTV serotypes showing little cross protection. The BTV serotype is mainly determined by genome segment 2 encoding the VP2 protein. Currently, inactivated and live-attenuated Bluetongue vaccines are available for a limited number of serotypes, but each of these have their specific disadvantages, including the inability to differentiate infected from vaccinated animals (DIVA). BTV non-structural proteins NS3 and NS3a are not essential for virus replication in vitro, but are important for cytopathogenic effect in mammalian cells and for virus release from insect cells in vitro. Recently, we have shown that virulent BTV8 without NS3/NS3a is non-virulent and viremia in sheep is strongly reduced, whereas local in vivo replication leads to seroconversion. Live-attenuated BTV6 without NS3/NS3a expression protected sheep against BTV challenge. Altogether, NS3/NS3a knockout BTV6 is a promising vaccine candidate and has been named Disabled Infectious Single Animal (DISA) vaccine. Here, we show serotype-specific protection in sheep by DISA vaccine in which only genome segment 2 of serotype 8 was exchanged. Similarly, DISA vaccines against other serotypes could be developed, by exchange of only segment 2, and could therefore safely be combined in multi-serotype cocktail vaccines with respect to reassortment between vaccine viruses. Additionally, NS3 antibody responses are raised after natural BTV infection and NS3-based ELISAs are therefore appropriate tools for DIVA testing accompanying the DISA vaccine. To enable DIVA, we developed an experimental NS3 ELISA. Indeed, vaccinated sheep remained negative for NS3 antibodies, whereas seroconversion for NS3 antibodies was associated with viremia after heterologous BTV challenge. PMID:25454873
Bagley, Clell V, DVM; Burrell, W. Craig
Bluetongue (BT) is a viral disease that is spread mainly by one specific type of gnat. Other gnats and blood sucking insects may occasionally transmit BT, but they are much less important in its transfer. Cattle are the main reservoir for overwintering of the virus in temperate climates. The gnats become infected from cattle and then spread the disease to other cattle and sheep as they take blood meals. It is also spread through infected semen and may be spread by blood sucking lice and a sof...
Maan, S; Maan, N S; Batra, K; Kumar, A; Gupta, A; Rao, Panduranga P; Hemadri, Divakar; Reddy, Yella Narasimha; Guimera, M; Belaganahalli, M N; Mertens, P P C
Bluetongue virus (BTV) infects all ruminants, including cattle, goats and camelids, causing bluetongue disease (BT) that is often severe in naïve deer and sheep. Reverse-transcription-loop-mediated-isothermal-amplification (RT-LAMP) assays were developed to detect eastern or western topotype of BTV strains circulating in India. Each assay uses four primers recognizing six distinct sequences of BTV genome-segment 1 (Seg-1). The eastern (e)RT-LAMP and western (w)RT-LAMP assay detected BTV RNA in all positive isolates that were tested (n=52, including Indian BTV-1, -2, -3, -5, -9, -10, -16, -21 -23, and -24 strains) with high specificity and efficiency. The analytical sensitivity of the RT-LAMP assays is comparable to real-time RT-PCR, but higher than conventional RT-PCR. The accelerated eRT-LAMP and wRT-LAMP assays generated detectable levels of amplified DNA, down to 0.216 fg of BTV RNA template or 108 fg of BTV RNA template within 60-90min respectively. The assays gave negative results with RNA from foot-and-mouth-disease virus (FMDV), peste des petits ruminants virus (PPRV), or DNA from Capripox viruses and Orf virus (n=10), all of which can cause clinical signs similar to BT. Both RT-LAMP assays did not show any cross-reaction among themselves. The assays are rapid, easy to perform, could be adapted as a 'penside' test making them suitable for 'front-line' diagnosis, helping to identify and contain field outbreaks of BTV. PMID:27054888
... virus titer using the titration method used in paragraph (c)(2) of this section. To be eligible for... Master Seed shall be tested for transmissibility and reversion to virulence in sheep using a method... TCID50 of bluetongue virus or another method acceptable to Animal and Plant Health Inspection Service....
Purse, B V; Tatem, A J; Caracappa, S; Rogers, D J; Mellor, P S; Baylis, M; Torina, A
Surveillance data from 268 sites in Sicily are used to develop climatic models for prediction of the distribution of the main European bluetongue virus (BTV) vector Culicoides imicola Kieffer (Diptera: Ceratopogonidae) and of potential novel vectors, Culicoides pulicaris Linnaeus, Culicoides obsoletus group Meigen and Culicoides newsteadi Austen. The models containing the 'best' climatic predictors of distribution for each species, were selected from combinations of 40 temporally Fourier-processed remotely sensed variables and altitude at a 1 km spatial resolution using discriminant analysis. Kappa values of around 0.6 for all species models indicated substantial levels of agreement between model predictions and observed data. Whilst the distributions of C. obsoletus group and C. newsteadi were predicted by temperature variables, those of C. pulicaris and C. imicola were determined mainly by normalized difference vegetation index (NDVI), a variable correlated with soil moisture and vegetation biomass and productivity. These models were used to predict species presence in unsampled pixels across Italy and for C. imicola across Europe and North Africa. The predicted continuous presence of C. pulicaris along the appenine mountains, from north to south Italy, suggests BTV transmission may be possible in a large proportion of this region and that seasonal transhumance (seasonal movement of livestock between upland and lowland pastures) even in C. imicola-free areas should not generally be considered safe. The predicted distribution of C. imicola distribution shows substantial agreement with observed surveillance data from Greece and Iberia (including the Balearics) and parts of mainland Italy (Lazio, Tuscany and areas of the Ionian coast) but is generally much more restricted than the observed distribution (in Sardinia, Corsica and Morocco). The low number of presence sites for C. imicola in Sicily meant that only a restricted range of potential C. imicola habitats were
Mintiens, K; Méroc, E; Mellor, P S; Staubach, C; Gerbier, G; Elbers, A R W; Hendrickx, G; De Clercq, K
In August 2006, bluetongue (BT) was notified in The Netherlands on several animal holdings. This was the onset of a rapidly spreading BT-epidemic in north-western Europe (latitude >51 degrees N) that affected cattle and sheep holdings in The Netherlands, Belgium, Germany, France and Luxembourg. The outbreaks were caused by bluetongue virus (BTV) serotype 8, which had not been identified in the European Union before. Bluetongue virus can be introduced into a free area by movement of infected ruminants, infected midges or by infected semen and embryos. In this study, information on animal movements or transfer of ruminant germ plasms (semen and embryos) into the Area of First Infection (AFI), which occurred before and during the onset of the epidemic, were investigated in order to establish the conditions for the introduction of this virus. All inbound transfers of domestic or wild ruminants, non-susceptible mammal species and ruminant germ plasms into the AFI during the high-risk period (HRP), registered by the Trade Control and Expert System (TRACES) of the EC, were obtained. Imports originating from countries with a known or suspected history of BTV-incidence of any serotype were identified. The list of countries with a reported history of BTV incidence was obtained from the OIE Handistatus II for the period from 1996 until 2004. No ruminants were imported from a Member State (MS) with a known history of BTV-8 or from any other country with a known or suspected history of BTV incidence of any serotype. Of all non-susceptible mammal species only 233 horses were transported directly into the AFI during the HRP. No importations of semen or embryos into the AFI were registered in TRACES during the period of interest. An obvious source for the introduction of BTV-8, such as import of infected ruminants, could not be identified and the exact origin and route of the introduction of BTV-8 thus far remains unknown. However, the absence of legal import of ruminants from
Leblanc, N; Rasmussen, Thomas Bruun; Fernandez, J;
A real-time RT-PCR assay based on the primer–probe energy transfer (PriProET) was developed to detect all 24 serotypes of bluetongue virus (BTV). BTV causes serious disease, primarily in sheep, but in other ruminants as well. A distinguishing characteristic of the assay is its tolerance toward...... tests showed no positive results for heterologous pathogens. The assay was tested on clinical samples from BTV 8 outbreaks in Sweden and Denmark in 2008. The lowest detection limit for that serotype, determined with PCR standards, was 57 genome copies. The assay sensitivity for some other serotypes that...... circulate currently in Europe was also determined. BTV 2, 4, 9 and 16 were tested on available cell culture samples and the detection limits were 109, 12, 13 and 24 copies, respectively. This assay provides an important tool for early and rapid detection of a wide range of BTV strains, including emerging...
Raj K. Singh
Full Text Available The authors describe the serological surveillance of bluetongue virus (BTV group-specific antibody in goats of the coastal saline (Sunderban area of West Bengal, India. A recombinant viral protein 7 (rVP7-based indirect enzyme-linked immunosorbent assay (ELISA was used to detect the antibody in sera. The bacterially expressed rVP7 was purified by affinity chromatography. The diagnostic performance of the assay was assessed by comparing it to the commercially available previously validated competitive ELISA. Using the control and 1 202 test sera, the cut-off value, sensitivity and specificity as well as other performance characteristics e.g. the Youden index, efficiency, positive and negative predictive value and prevalence were estimated. Field-collected goat sera (n = 1 202 were tested and a serological prevalence rate of 47% was observed in the study area.
Veldhuis, Anouk; Brouwer-Middelesch, Henriëtte; Marceau, Alexis; Madouasse, Aurélien; Van der Stede, Yves; Fourichon, Christine; Welby, Sarah; Wever, Paul; van Schaik, Gerdien
This study aimed to evaluate the use of routinely collected reproductive and milk production data for the early detection of emerging vector-borne diseases in cattle in the Netherlands and the Flanders region of Belgium (i.e., the northern part of Belgium). Prospective space-time cluster analyses on residuals from a model on milk production were carried out to detect clusters of reduced milk yield. A CUSUM algorithm was used to detect temporal aberrations in model residuals of reproductive performance models on two indicators of gestation length. The Bluetongue serotype-8 (BTV-8) epidemics of 2006 and 2007 and the Schmallenberg virus (SBV) epidemic of 2011 were used as case studies to evaluate the sensitivity and timeliness of these methods. The methods investigated in this study did not result in a more timely detection of BTV-8 and SBV in the Netherlands and BTV-8 in Belgium given the surveillance systems in place when these viruses emerged. This could be due to (i) the large geographical units used in the analyses (country, region and province level), and (ii) the high level of sensitivity of the surveillance systems in place when these viruses emerged. Nevertheless, it might be worthwhile to use a syndromic surveillance system based on non-specific animal health data in real-time alongside regular surveillance, to increase the sense of urgency and to provide valuable quantitative information for decision makers in the initial phase of an emerging disease outbreak. PMID:26732291
Gu, Xingnian; Davis, Rodney J; Walsh, Susan J; Melville, Lorna F; Kirkland, Peter D
Infection with Bluetongue virus (BTV) is a significant impediment to the global movement of bovine semen. Repeat testing of blood from donor animals is specified in the World Organization for Animal Health (OIE) Manual for the export of semen from regions where BTV may be present. Screening of blood or semen samples has usually been carried out by virus isolation (VI) either by inoculation of chicken embryos followed by passage onto insect and mammalian cell cultures or in vivo inoculation of sheep followed by serology to detect seroconversion. Direct testing of semen for BTV would enable earlier release of semen samples and avoid repeat testing of the donor, as well as provide an option for releasing batches of semen that were collected without certification of the donor. Quantitative (real-time) reverse transcription polymerase chain reaction (qRT-PCR) assays overcome most of the limitations of other methods and have the potential to provide higher sensitivity. The present study compared 5 qRT-PCR assays, including 2 commercially available kits, for the detection of BTV in semen serially collected from 8 bulls over a period of 90 days after experimental infection. The results of the study show that at least one of the qRT-PCR assays is extremely reproducible and has both very high sensitivity and specificity to reliably detect all available serotypes. The preferred qRT-PCR gave consistently superior results to VI, sheep inoculation, and conventional RT-PCR. Therefore, the assay can be recommended for the screening of bovine semen for freedom from BTV. PMID:24532692
Lorusso, Alessio; Baba, Doumbia; Spedicato, Massimo; Teodori, Liana; Bonfini, Barbara; Marcacci, Maurilia; Di Provvido, Andrea; Isselmou, Katia; Marini, Valeria; Carmine, Irene; Scacchia, Massimo; Di Sabatino, Daria; Petrini, Antonio; Bezeid, Beyatt Ahmed; Savini, Giovanni
In March 2013, EDTA-blood and serum samples were collected from 119 cattle and 159 dromedaries at the slaughterhouse of Nouakchott, the capital city of the Islamic Republic of Mauritania. Serum samples were screened for the presence of Bluetongue (BT) antibodies by competitive ELISA (cELISA). Positive samples were then tested by serum-neutralization (SN) to determine BTV serotype. RNA from blood samples was first tested by a genus-specific quantitative RT-PCR assay which is able to detect all 27 existing BTV serotypes (RT-qPCR1-27). Positive samples were further screened by a RT-qPCR assay which, instead, is able to detect the classical 24 BTV serotypes only (RT-qPCR1-24). Of the 278 serum samples tested, 177 (mean=63.7%; 95% CI: 57.9%-69.1%) resulted positive by cELISA. Of these, 69 were from cattle (mean=58.0%; 95% CI: 49.0%-66.5%) and 108 from dromedaries (mean=67.9%; 95% CI: 60.3%-74.7%). BTV-26 neutralizing antibodies were by far the most frequently found as they were detected in 146 animals with titres ranging from 1:10 to 1:80. Out of 278 blood samples, 25 (mean=9.0%; 95% CI: 6.2%-12.9%) were found positive for BTV by RT-qPCR1-27, 20 (mean=16.8%; 95% CI: 11.2%-24.6%) were from cattle and 5 (mean=3.1%; 95% CI: 1.4%-7.1%) from dromedaries. When tested by RT-qPCR1-24 the 25 BTV positive samples were negative. Unfortunately, no genetic information by molecular typing or by next generation sequencing has been obtained as for the very low levels of RNA in the blood samples. PMID:26932578
Ali Ahmed Al-Eesa
Full Text Available Aim: To estimate the prevalence and distribution of serum antibodies to BTV in different domesticated animals in different localities of Saudi Arabia. Materials and Methods: A total of 4845 field sera collected from different animal species within 10 districts in the Kingdom of Saudi Arabia were screened for the presence of group-specific BTV antibodies by competitive ELISA (c ELISA. Results: The overall BTV antibody prevalence was 54.1%, 53.3%, 44.8% and 25.7% in sheep, goat, cattle and camel respectively (at 95% confidence level. The Jizan and Eastern Province districts were the regions with the highest prevalence resulting 65.8% of sheep, 68.2% of goats, 49.3% of cattle, 44% of camel in Jizan and 65.8% of sheep, 62.5% of goats, 53.4% of cattle, 28.5% of camel in Eastern Province positive to c-ELISA. The second highest rate was in Najran district where the seropositivity for Bluetongue was found to be 60% of sheep, 57.9% of goats, 47.2% of cattle and 29.3% of camel. Our results recorded positive animals in all examined districts which indicate serological evidence of exposure to infection was widely distributed all over the country. Conclusions: These results demonstrate the high occurrence of the BTV that emphasize the necessity to a well-defined control strategy for preventing and controlling the BTV in Saudi Arabia. [Vet. World 2012; 5(7.000: 389-393
Full Text Available BACKGROUND: Bluetongue (BT is a vector-borne disease of ruminants that has expanded its traditional global distribution in the last decade. Recently, BTV-1 emerged in Southern Spain and caused several outbreaks in livestock reaching the north of the country. The aim of this paper was to review the emergence of BTV-1 in the Basque Country (Northern Spain during 2007 and 2008 analyzing the possibility that infected Culicoides were introduced into Basque Country by winds from the infected areas of Southern Spain. METHODOLOGY/PRINCIPAL FINDINGS: We use a complex HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory model to draw wind roses and backward wind trajectories. The analysis of winds showed September 28 to October 2 as the only period for the introduction of infected midges in the Basque Country. These wind trajectories crossed through the areas affected by serotype 1 on those dates in the South of the Iberian Peninsula. Additionally meteorological data, including wind speed and humidity, and altitude along the trajectories showed suitable conditions for Culicoides survival and dispersion. CONCLUSIONS/SIGNIFICANCE: An active infection in medium-long distance regions, wind with suitable speed, altitude and trajectory, and appropriate weather can lead to outbreaks of BTV-1 by transport of Culicoides imicola, not only over the sea (as reported previously but also over the land. This shows that an additional factor has to be taken into account for the control of the disease which is currently essentially based on the assumption that midges will only spread the virus in a series of short hops. Moreover, the epidemiological and serological data cannot rule out the involvement of other Culicoides species in the spread of the infection, especially at a local level.
Full Text Available Vaccination is one of the most efficient ways to control the spread of infectious diseases. Simulations are now widely used to assess how vaccination can limit disease spread as well as mitigate morbidity or mortality in susceptible populations. However, field studies investigating how much vaccines decrease the velocity of epizootic wave-fronts during outbreaks are rare. This study aimed at investigating the effect of vaccination on the propagation of bluetongue, a vector-borne disease of ruminants. We used data from the 2008 bluetongue virus serotype 1 (BTV-1 epizootic of southwest France. As the virus was newly introduced in this area, natural immunity of livestock was absent. This allowed determination of the role of vaccination in changing the velocity of bluetongue spread while accounting for environmental factors that possibly influenced it. The average estimated velocity across the country despite restriction on animal movements was 5.4 km/day, which is very similar to the velocity of spread of the bluetongue virus serotype 8 epizootic in France also estimated in a context of restrictions on animal movements. Vaccination significantly reduced the propagation velocity of BTV-1. In comparison to municipalities with no vaccine coverage, the velocity of BTV-1 spread decreased by 1.7 km/day in municipalities with immunized animals. For the first time, the effect of vaccination has been quantified using data from a real epizootic whilst accounting for environmental factors known to modify the velocity of bluetongue spread. Our findings emphasize the importance of vaccination in limiting disease spread across natural landscape. Finally, environmental factors, specifically those related to vector abundance and activity, were found to be good predictors of the velocity of BTV-1 spread, indicating that these variables need to be adequately accounted for when evaluating the role of vaccination on bluetongue spread.
Characterizing the Epidemiology of Bluetongue Virus Serotype 1 in Southern Louisiana. Will K. Reeves, Mike Becker, Cecilia Kato, Richard Mayer, and Lane D. Foil. In November 2004, BTV-1 was isolated from the tissues of a hunter-killed white tailed deer from southern Louisiana. There was signif...
Vahid Najarnezhad; Mahin Rajae
To estimate the prevalence and distribution of bluetongue virus antibody in sheep and goats in 25 townships of Khorasan Razavi. Bluetongue is an infectious, non-contagious, arthropod born viral disease of ruminants and has been reported from most of the tropical and subtropical regions of the world. Methods: A total number of 1 034 serum samples from sheep and goats were collected and transmitted to Serological Laboratory of Veterinary Council of Khorasan Razavi. Serums were screened for the presence of group-specific bluetongue virus antibody using competitive Enzyme Linked Immuno Sorbent Assay (c-ELISA). Results: The seropositivity of sheep and goats for bluetongue was found to be 89.2%. The highest prevalence rate was seen in Taybad, Khalil-abad and Torbat-jam (100%) and the least prevalence rate was seen in Jovein (55%). Conclusions: The results showed that the majority of animals in the north-east of Iran are infected with bluetongue virus. High correlation between abortion history and seroposivity emphasize the economical importance of bluetongue virus in the sheep herds of the region.
Bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV) are arthropod-transmitted viruses in the genus Orbivirus of the family Reoviridae. These viruses infect a variety of domestic and wild ruminant hosts, although the susceptibility to clinical disease associated with BTV or EHDV inf...
MacLachlan, N J; Crafford, J E; Vernau, W; Gardner, I A; Goddard, A; Guthrie, A J; Venter, E H
Sheep inoculated with a virulent South African strain of bluetongue (BT) virus serotype 4 developed severe clinical signs and lesions characteristic of fulminant BT, including coronitis, hemorrhage and ulceration of the mucosal lining of the oral cavity and forestomaches, hemorrhage in the wall of the pulmonary artery, and focally extensive necrosis of skeletal muscle, especially of the neck. At necropsy, up to 14 days after infection, the infected sheep exhibited striking pulmonary edema, edema of the subcutaneous tissues and fascial planes of the head and neck, and pleural and pericardial effusion of varying severity. A reliable model for experimental reproduction of fulminant BT in sheep will facilitate future studies to better characterize the pathogenesis of this disease, particularly as it regards the mechanisms responsible for the increased vascular permeability that characterizes BT and related orbiviral diseases such as African horse sickness. PMID:18487487
Full Text Available Aim: With the aim of revealing the epidemiological intricacies of bluetongue (BT in the southern part of West Bengal state, the present study was undertaken to assess seroprevalence of BT along with identification of the vector of the disease, i.e., Culicoides midges available in the region in their breeding season with conducive environmental factors, if any. Materials and Methods: A total of 1509 (sheep-504, goat-1005 samples were collected from three different agroclimatic zones of South Bengal viz. new alluvial, red laterite and coastal saline. To detect anti-BT antibodies in the collected serum samples, indirect-enzyme-linked immunosorbent assay (i-ELISA was performed. Culicoides midges were collected from those agro-climatic zones of South Bengal for species identification. The meteorological parameters, viz. temperature (maximum and minimum, rainfall and relative humidity of three agro-climatic zones of South Bengal were analyzed for the months of July to December during 2010-2013. Results: The overall seropositivity was 33.13% and 30.24% in sheep and goat, respectively as assessed by i-ELISA. In South Bengal, the predominant species of Culicoides found were Culicoides schultzei, Culicoides palpifer and Culicoides definitus. Conclusion: Since virus transmitting species of Culicoides midges could be detected in South Bengal, besides high seropositivity in ruminants, the possibility of circulating BT virus in South Bengal is quite imminent.
Full Text Available The objective of this study was to describe the seroprevalence rates of bluetongue virus (BTV in sheep in west and northwest provinces of Iran. Bluetongue virus, an economically important orbivirus of the Reoviridae family, causes a hemorrhagic disease mainly in sheep and occasionally in cattle and some species of deer. Bluetongue virus is transmitted between its mammalian hosts by certain species of biting midges (Culicoides spp. and it can infect all ruminant species. Overall, 26 serotypes have been reported around the world. Due to its economic impact, bluetongue (BT is an Office of International des Epizooties (OIE-listed disease. A total of 756 sera samples collected during 2007-2008, were available. Sera were tested with competitive enzyme-linked immunosorbent assay (C-ELISA. The seroprevalence rate in sheep was 40.87%. The rate of positivity in sheep in west and northwest was 46.10% and 33.75%, respectively. The highest prevalence of antibodies in serum was in West Azerbaijan (64.86%, and lower was in Ardabil (23.77%.
Allen, Andrew J; Stanton, James B; Evermann, James F; Fry, Lindsay M; Ackerman, Melissa G; Barrington, George M
In late summer/early fall of 2013, 2 South American camelids from central Washington were diagnosed with fatal bluetongue viral disease, an event which is rarely reported. A 9-year-old intact male llama (Lama glama), with a 1-day history of anorexia, recumbency, and dyspnea before death. Abundant foam discharged from the mouth and nostrils, and the lungs were severely edematous on postmortem examination. Histologically, there was abundant intra-alveolar edema with fibrin. Hemorrhage and edema disrupted several other organs. Bluetongue viral RNA was detected by reverse transcription polymerase chain reaction (RT-PCR), and serotype 11 was identified by sequencing a segment of the VP2 outer capsid gene. Approximately 1 month later, at a site 150 miles north of the index case, a 2-year-old female alpaca with similar, acutely progressive clinical signs was reported. A postmortem examination was performed, and histologic lesions from the alpaca were similar to those of the llama, and again serotype 11 was detected by PCR. The occurrence of bluetongue viral infection and disease is described in the context of seasonal Bluetongue virus activity within the northwestern United States and southwestern Canada. PMID:25680921
Adriana Hellmeister de Campos Nogueira
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Zimmer, JY.; Saegerman, C; Martinelle, L.; Losson, B.; Leroy, P.; Haubruge, E.; Francis, F.
Pig farms: reservoirs of vectors of Bluetongue and Schmallenberg viruses?. Bluetongue (BT) is a vector-borne disease that affects domestic and wild ruminants. Since its recent outbreak in northern Europe, this viral disease has caused considerable economic losses. The biological vectors of the bluetongue virus are biting midges belonging to the genus Culicoides (Diptera: Ceratopogonidae). Several light trapping campaigns targeting these adult midges have been previously conducted in Belgium w...
New strategies for preventing bluetongue in sheep, W.K. Reeves. Bluetongue disease is a sporadic and unpredictable disease in the northern Rocky Mountains. Epizootics can be separated by decades of little to no disease activity. Woolgrowers need access to control technologies that can be used after ...
This paper presents the report of the `Bluetongue and Bovine Retrovirus Committee' meeting held October 21, 2002 during the annual meeting of the United States Animal Health Association in St. Louis, Missouri. An update was given on diagnostic observations for bluetongue, epizootic hemorrhagic dise...
Nigel Gibbens, the UK's Chief Veterinary Officer, gives an update on the developing bluetongue situation in France and explains how vets can help their clients prepare for possible outbreaks in the UK this summer. PMID:27103689
Drolet, B.S.; Reister, L.M.; Lehiy, C.J.; Rijn, van P.A.; Bowen, R.A.
The severity of Bluetongue clinical disease in ruminants varies greatly depending on the outbreak serotype/strain, animal species/breed, and immune status of the herd. To predict disease risk from any of the 26 Bluetongue virus (BTV) serotypes identified to date, experimental animal susceptibility s
王肖; 张杰; 杜贤进; 周晓光
Objective: To investigate the characteristics and the mechanism of bluetongue virus strain HbC3(HCMV) infecting mouse prostate cancer RM-1 cells in vitro.Methods: BTV-HbC3 was used to infect RM-1 cells, the the cytopathic effect (CPE) was observed, and the inhibition activity of RM-1 cell infected with BTV-HbC3 was determined by MTT.Transmission electron microscope (TEM) was adopted to study the changes of cell ultrastructure.DNA Ladder was taken to detect the apoptosis of RM-1 cells induced by BTV-HbC3.The apoptosis was detected by flow cytometry (FCM).Results: RM-1 cells were sensitive to BTV-HbC3 infection, CPE was found in BTV-HbC3 infected RM-1 cells, and lots of virus particles were found in cytoplasm by TEM.Apoptotic cells were detected by FCM.Conclusion: BTV-HbC3 could infect RM-1 cells and replicate efficiently, and induce apoptosis in tumor cells.%目的:体外研究蓝舌病毒湖北株3(BTV-HbC3)对小鼠前列腺癌细胞RM-1的感染性并探讨BTV-HbC3靶向性溶瘤的机制.方法:观察RM-1细胞感染BTV-HbC3的细胞病变效应;MTT法研究病毒致细胞病变率的特征;透射电镜观察感染病毒后细胞超微结构的变化;DNA Ladder分析病毒诱导细胞凋亡的情况;流式细胞仪测定病毒对RM-1细胞凋亡的影响.结果:BTV-HbC3感染RM-1细胞后有明显的细胞病变效应;DNA Ladder分析为阶梯状条带;透射电镜发现胞质内有大量病毒颗粒和典型细胞凋亡形态变化;流式细胞仪可见明显的细胞凋亡.结论:BTV-HbCs在体外能有效的感染RM-1细胞,并能诱导RM-1细胞凋亡.
This technical report was produced to make public the code produced as the main project of the PhD project by Kaare Græsbøll, with the title: "Modelling spread of Bluetongue and other vector borne diseases in Denmark and evaluation of intervention strategies".......This technical report was produced to make public the code produced as the main project of the PhD project by Kaare Græsbøll, with the title: "Modelling spread of Bluetongue and other vector borne diseases in Denmark and evaluation of intervention strategies"....
Miguel Angel eJimenez-Clavero
Full Text Available Environmental changes have an undoubted influence on the appearance, distribution and evolution of infectious diseases, and notably on those transmitted by vectors. Global change refers to environmental changes arising from human activities affecting the fundamental mechanisms operating in the biosphere. This paper discusses the changes observed in recent times with regard to some important arboviral (arthropod-borne viral diseases of animals, and the role global change could have played in these variations. Two of the most important arboviral diseases of animals, bluetongue and West Nile fever/encephalitis, have been selected as models. In both cases, in the last 15 years an important leap forward has been observed, which has lead to considering them emerging diseases in different parts of the world. Bluetongue, affecting domestic ruminants, has recently afflicted livestock in Europe in an unprecedented epizootic, causing enormous economic losses. West Nile fever/encephalitis affects wildlife (birds, domestic animals (equines and humans, thus, beyond the economic consequences of its occurrence, as a zoonotic disease, it poses an important public health threat. West Nile virus has expanded in the last 12 years worldwide, and particularly in the Americas, where it first occurred in 1999, extending throughout the Americas relentlessly since then, causing a severe epidemic of disastrous consequences for public health, wildlife and livestock. In Europe, West Nile virus is known long time ago, but it is since the last years of the XXth century that its incidence has risen substantially. Circumstances such as global warming, changes in land use and water management, increase in travel, trade of animals, and others, can have an important influence in the observed changes in both diseases. The following question is raised: What is the contribution of global changes to the current increase of these diseases in the world?
Full Text Available Bluetongue is an arboviral disease of ruminants causing significant economic losses. Our risk assessment is based on the epidemiological key parameter, the basic reproduction number. It is defined as the number of secondary cases caused by one primary case in a fully susceptible host population, in which values greater than one indicate the possibility, i.e., the risk, for a major disease outbreak. In the course of the Bluetongue virus serotype 8 (BTV-8 outbreak in Europe in 2006 we developed such a risk assessment for the University of Veterinary Medicine Vienna, Austria. Basic reproduction numbers were calculated using a well-known formula for vector-borne diseases considering the population densities of hosts (cattle and small ruminants and vectors (biting midges of the Culicoides obsoletus spp. as well as temperature dependent rates. The latter comprise the biting and mortality rate of midges as well as the reciprocal of the extrinsic incubation period. Most important, but generally unknown, is the spatio-temporal distribution of the vector density. Therefore, we established a continuously operating daily monitoring to quantify the seasonal cycle of the vector population by a statistical model. We used cross-correlation maps and Poisson regression to describe vector densities by environmental temperature and precipitation. Our results comprise time series of observed and simulated Culicoides obsoletus spp. counts as well as basic reproduction numbers for the period 2009-2011. For a spatio-temporal risk assessment we projected our results from the location of Vienna to the entire region of Austria. We compiled both daily maps of vector densities and the basic reproduction numbers, respectively. Basic reproduction numbers above one were generally found between June and August except in the mountainous regions of the Alps. The highest values coincide with the locations of confirmed BTV cases.
Kyriakis, C S; Billinis, C; Papadopoulos, E; Vasileiou, N G C; Athanasiou, L V; Fthenakis, G C
Bluetongue is an arthropod-borne viral disease of ruminants, especially of sheep, caused by Bluetongue virus, which belongs to the genus Orbivirus of the family Reoviridae and is classified into 26 antigenically distinct serotypes. Once thought to be restricted in Africa and parts of the Middle East, bluetongue has now become a concern in sheep-rearing countries around the world. In the past 10 years, severe outbreaks have occurred in Europe with important economic consequences; of these, the 2006-20008 outbreak in Europe was caused by a serotype 8 strain and the 2014 outbreak in Greece and the other countries of south-east Europe was caused by a serotype 4 strain, suggested to be a reassortant strain with genome segments from lineages of serotype 1, 2 and 4. Immunisation campaigns can be implemented for successful control and limiting of the disease. Nevertheless, in both of the above outbreaks, late application of vaccinations led to a wide spread of the disease, which subsequently resulted in significant losses in livestock in the affected regions. In view of that, standardisation of control measures in the future will be beneficial for efficiently limiting outbreaks of the disease. PMID:26304745
M. A. Mahmoud
Full Text Available Aim: The study was undertaken to understand the epidemiological status of bluetongue infection in Egypt. Materials and Methods: Serum samples were collected from clinically healthy as well as suspected sheep and goats. Samples were collected during the vector breeding season from September to November 2010, from 14 Egyptian governorates which represent different geographical regions of Egypt, and were tested by Agar Gel Immuno-precipitation Test (AGPT. Results: Out of total 1293 animal serum samples (sheep-1028 and goats-265, 17.5% of sheep and 14.7% of goats serum samples were found positive. The overall prevalence of anti-BT antibodies in different governorates was 16.9%. The highest prevalence of bluetongue group specific antibodies was detected in Beni-Suef, Giza, and Al Sharqia governorates (13.2%. The results indicate that there is a necessity to run further studies to identify the negative governorates. In addition, there is a lack in information regarding the BTV serotypes in Egypt. Conclusion: This study reflected high seroprevalence of bluetongue infection in sheep than goats. The results indicated that further studies are needed to identify the vectors from different agro-climatic zones, in addition, the BTV serotypes that are circulating in Egypt.
Full Text Available Bluetongue (BT, peste des petits ruminants (PPR and sheep pox are the most economically important viral diseases of sheep in India. Serum samples obtained from sheep in five northern states of the country were screened for antibody against these agents to explore the extent of spread of these infections. A total of 516 serum samples were screened for the presence of antibodies against BT and PPR viruses. Of these, 155 samples were also tested for antibodies against sheep pox virus. BT antibodies were found in 293 (56.8% animals, PPR virus antibodies in 215 (41.7% and sheep pox virus antibodies in 106 (68.3%. Of the serum samples tested, 25.2% were positive for antibodies against all three viruses. These findings clearly demonstrated not only the enzootic nature of disease, but also the co-existence of antibodies to more than one of these viruses which would indicate that concurrent infections were common. Therefore, control measures should focus in combating all three diseases simultaneously by exploring the possibility of a trivalent vaccine or the use of multiple genes expressing vectored vaccine.
Drolet, Barbara S; Reister-Hendricks, Lindsey M; Podell, Brendan K; Breitenbach, Jonathan E; McVey, D Scott; van Rijn, Piet A; Bowen, Richard A
Bluetongue virus (BTV) is an orbivirus transmitted by biting midges (Culicoides spp.) that can result in moderate to high morbidity and mortality primarily in sheep and white-tailed deer. Although only 5 serotypes of BTV are considered endemic to the United States, as many as 11 incursive serotypes have been detected in livestock and wildlife in the past 16 years. Introductions of serotypes, with unknown virulence and disease risk, are constant threats to US agriculture. One potential incursive serotype of particular concern is the European strain of BTV-8, which was introduced into Northern Europe in 2006 and caused unprecedented livestock disease and mortality during the 2006-2007 vector seasons. To assess disease risk of BTV-8 in a common white-faced American sheep breed, eight Polled Dorset yearlings were experimentally infected and monitored for clinical signs. Viremia and viral tissue distribution were detected and quantified by real-time qRT-PCR. Overall, clinical disease was moderate with no mortality. Viremia reached as high as 9.7 log10 particles/mL and persisted at 5 logs or higher through the end of the study (28 days). Virus distribution in tissues was extensive with the highest mean titers at the peak of viremia (day 8) in the kidney (8.38 log10 particles/mg) and pancreas (8.37 log10 particles/mg). Virus persisted in tissues of some sheep at 8 logs or higher by day 28. Results of this study suggest that should BTV-8 emerge in the United States, clinical disease in this common sheep breed would likely be similar in form, duration, and severity to what is typically observed in severe outbreaks of endemic serotypes, not the extraordinary disease levels seen in Northern Europe. In addition, a majority of exposed sheep would be expected to survive and act as significant BTV-8 reservoirs with high titer viremias for subsequent transmission to other livestock and wildlife populations. PMID:27111674
Udbruddene i Nordvesteuropa af tropesygdommene bluetongue type 8 (2006-2009), bluetongue type 1 (2008) og schmallenberg (2011-12) er overraskende. Det er især overraskende, fordi de alle har spredt sig voldsomt og hurtigt, mens sygdomme, der spreder sig til nye miljøer og klimazoner, forventes at...
Joel K Kelso
Full Text Available The spread of Bluetongue virus (BTV among ruminants is caused by movement of infected host animals or by movement of infected Culicoides midges, the vector of BTV. Biologically plausible models of Culicoides dispersal are necessary for predicting the spread of BTV and are important for planning control and eradication strategies.A spatially-explicit simulation model which captures the two underlying population mechanisms, population dynamics and movement, was developed using extensive data from a trapping program for C. brevitarsis on the east coast of Australia. A realistic midge flight sub-model was developed and the annual incursion and population establishment of C. brevitarsis was simulated. Data from the literature was used to parameterise the model.The model was shown to reproduce the spread of C. brevitarsis southwards along the east Australian coastline in spring, from an endemic population to the north. Such incursions were shown to be reliant on wind-dispersal; Culicoides midge active flight on its own was not capable of achieving known rates of southern spread, nor was re-emergence of southern populations due to overwintering larvae. Data from midge trapping programmes were used to qualitatively validate the resulting simulation model.The model described in this paper is intended to form the vector component of an extended model that will also include BTV transmission. A model of midge movement and population dynamics has been developed in sufficient detail such that the extended model may be used to evaluate the timing and extent of BTV outbreaks. This extended model could then be used as a platform for addressing the effectiveness of spatially targeted vaccination strategies or animal movement bans as BTV spread mitigation measures, or the impact of climate change on the risk and extent of outbreaks. These questions involving incursive Culicoides spread cannot be simply addressed with non-spatial models.
Guis, Hélène; Tran, Annelise; de La Rocque, Stéphane; Baldet, Thierry; Gerbier, Guillaume; Barragué, Bruno; Biteau-Coroller, Fabienne; Roger, François; Viel, Jean-François; Mauny, Frédéric
The recent and rapid spread in the Mediterranean Basin of bluetongue, a viral disease of ruminants transmitted by some species of Culicoides (biting midges), highlights the necessity of determining the conditions of its emergence. This study uses high spatial resolution satellite imagery and methods from landscape ecology science to identify environmental parameters related to bluetongue occurrence in Corsica, a French Mediterranean island where the disease occurred for the first time in 2000. A set of environmental variables recorded in the neighborhood of 80 sheep farms were related to case occurrence through a logistic regression model computed within three subsequent buffer distances of 0.5, 1 and 2 km. The results reveal the role of landscape metrics, particularly those characterizing land-use units such as prairies and woodlands, as well as farm type, latitude and sunshine to explain the presence of bluetongue. Internal and external validation both indicate that the best results are obtained with the 1 km buffer size model (area under Receiver Operating Characteristic curve = 0.9 for internal validation and 0.81 for external validation). The results show that high spatial resolution remote sensing (i.e. 10 m pixels) and landscape ecology approaches contribute to improving the understanding of bluetongue epidemiology. PMID:17583664
The main outcome of this PhD project is a generic model for non-contagious infectious vector-borne disease spread by one vector species between up to two species of hosts distributed on farms and pasture. The model features a within-herd model of disease, combined with a triple movement kernel that...... describes spread of disease using vectors or hosts as agents of the spread. The model is run with bluetongue as the primary case study, and it is demonstrated how an epidemic outbreak of bluetongue 8 in Denmark is sensitive to the use of pasture, climate, vaccination, vector abundance, and flying parameters....... In constructing a more process oriented agent-based approach to spread modeling new parameters describing vector behavior were introduced. When these vector flying parameters have been quantified by experiments, this model can be implemented on areas naïve to the modeled disease with a high...
Full Text Available Abstract Background The design of veterinary and public health surveillance systems has been improved by the ability to combine Geographical Information Systems (GIS, mathematical models and up to date epidemiological knowledge. In Switzerland, an early warning system was developed for detecting the incursion of the bluetongue disease virus (BT and to monitor the frequency of its vectors. Based on data generated by this surveillance system, GIS and transmission models were used in order to determine suitable seasonal vector habitat locations and risk periods for a larger and more targeted surveillance program. Results Combined thematic maps of temperature, humidity and altitude were created to visualize the association with Culicoides vector habitat locations. Additional monthly maps of estimated basic reproduction number transmission rates (R0 were created in order to highlight areas of Switzerland prone to higher BT outbreaks in relation to both vector activity and transmission levels. The maps revealed several foci of higher risk areas, especially in northern parts of Switzerland, suitable for both vector presence and vector activity for 2006. Results showed a variation of R0 values comparing 2005 and 2006 yet suggested that Switzerland was at risk of an outbreak of BT, especially if the incursion arrived in a suitable vector activity period. Since the time of conducting these analyses, this suitability has proved to be the case with the recent outbreaks of BT in northern Switzerland. Conclusion Our results stress the importance of environmental factors and their effect on the dynamics of a vector-borne disease. In this case, results of this model were used as input parameters for creating a national targeted surveillance program tailored to both the spatial and the temporal aspect of the disease and its vectors. In this manner, financial and logistic resources can be used in an optimal way through seasonally and geographically adjusted
Hendrickx, Guy; Gilbert, Marius; Staubach, Christoph; Elbers, Armin; Mintiens, Koen; Gerbier, Guillaume; Ducheyne, Els
Increased transport and trade as well as climate shifts play an important role in the introduction, establishment and spread of new pathogens. Arguably, the introduction of bluetongue virus (BTV) serotype 8 in Benelux, Germany and France in 2006 is such an example. After its establishment in receptive local vector and host populations the continued spread of such a disease in a suitable environment will mainly depend on movement of infected vectors and animals. In this paper we explore how wind models can contribute to explain the spread of BTV in a temperate eco-climatic setting. Based on previous work in Greece and Bulgaria filtered wind density maps were computed using data from the European Centre for Medium-Range Weather Forecasts (ECMWF). Six hourly forward wind trajectories were computed at pressure levels of 850 hPa for each infected farm as from the recorded onset of symptoms. The trajectories were filtered to remove wind events that do not contribute to possible spread of the vector. The suitable wind events were rastered and aggregated on a weekly basis to obtain weekly wind density maps. Next to this, cumulated wind density maps were also calculated to assess the overall impact of wind dispersal of vectors. A strong positive correlation was established between wind density data and the horizontal asymmetrical spread pattern of the 2006 BTV8 epidemic. It was shown that short (31 km) distance spread had a different impact on disease spread. Computed wind densities were linked to the medium/long-distance spread whilst short range spread was mainly driven by active Culicoides flight. Whilst previous work in the Mediterranean basin showed that wind driven spread of Culicoides over sea occurred over distances of up to 700 km, this phenomenon was not observed over land. Long-distance spread over land followed a hopping pattern, i.e. with intermediary stops and establishment of local virus circulation clusters at distances of 35-85 km. Despite suitable wind
Berisha, Betim; Goga, Izedin; Hulaj, Beqë; Çaushi, Driton; Sherifi, Kurtesh; Wilsmore, Anthony J; Taylor, William P
Clinical bluetongue (BT) caused by BT virus serotype 9 (BTV-9) was observed in Kosova in 2001 and, although subsequently no further clinical cases was diagnosed, its continuing presence has been demonstrated by serological tests in cattle, sheep and goats. In this study, light traps were placed in stables near Prishtinë to identify possible vectors of BTV in Kosova. Samples were collected from October 2004 until the end of 2006. Culicoides were identified and speciated and results were plotted against temperature data. Samples contained Obsoletus and Pulicaris Complexes but not C. imicola. The first specimens of Culicoides were collected in April and they continued to be detected until November. Generally, Obsoletus Complex was present in the largest numbers, with the exception of the middle of the year when the Pulicaris Complex predominated. The number of Culicoides trapped was directly linked to temperature (p<0.05) and records indicated that Culicoides activity ceased when minimum temperatures fell below 0°C; activity recommenced when minimum temperatures rose to approximately 6°C. These results indicate that there was a lack of a vector for BTV during winter for a period lasting approximately five months. PMID:21132628
Full Text Available Clinical bluetongue (BT caused by BT virus serotype 9 (BTV‑9 was observed in Kosova in 2001 and, although subsequently no further clinical cases was diagnosed, its continuing presence has been demonstrated by serological tests in cattle, sheep and goats. In this study, light traps were placed in stables near Prishtinë to identify possible vectors of BTV in Kosova. Samples were collected from October 2004 until the end of 2006. Culicoides were identified and speciated and results were plotted against temperature data. Samples contained Obsoletus and Pulicaris Complexes but not C. imicola. The first specimens of Culicoides were collected in April and they continued to be detected until November. Generally, Obsoletus Complex was present in the largest numbers, with the exception of the middle of the year when the Pulicaris Complex predominated. The number of Culicoides trapped was directly linked to temperature (p<0.05 and records indicated that Culicoides activity ceased when minimum temperatures fell below 0°C; activity recommenced when minimum temperatures rose to approximately 6°C. These results indicate that there was a lack of a vector for BTV during winter for a period lasting approximately five months.
Pacheco, Solange Almeida
RESUMO - Análise do risco da ocorrência de vectores da Língua Azul com base em Sistemas de Informação Geográfica e modelos estatísticos. - A Língua Azul (LA) está entre as doenças da lista da Organização Mundial de Saúde Animal (OIE) devido ao seu potencial de rápida disseminação e do grave impacto económico na pecuária. No passado, devido à sua epidemiologia, apenas os países do sul da Europa eram afectados pela doença. No entanto, no segundo semestre de 2006, um surto sem ...
Yin, Hui-Qiong; Xiao, Rui; Rong, Zhen; Jin, Pei-Pei; Ji, Chang-Fu; Zhang, Jin-Gang
The evanescent wave fiber immunosensors (EWFI) technique was developed for the real-time rapidly sensitive and specific detection of the monoclonal antibody 3E2 of BTV. The outer-core protein VP7 of BTV was labled on the surface of the exposed fiber-optic core. The monoclonal antibody 3E2 of BTV VP7 were added and then the goat ant-rat IgG conjugated with Cy3 was captured. After the 532nm pulse (excitation source) reached the fiber probe, evanescent wave was generated, which excited the Cy3 bound to the immuno-complex and produced the fluorescent signal, which was changed into electrical signals read through computer. The preliminary results suggested that a detection limit of 10ng/ml was measured for the monoclonal antibody 3E2, which is equal to the sensitivity of ELISA. The 3E2 sample was specifically detected through the EWFI assay in 15min, and the fiber can be recycled at least ten times through TEA solution condition. This developed EWFI was a real-time rapidly sensitive and specific way for the detection of BTV antibodies. PMID:25982137
Reperant, L A; Brown, I H; Haenen, O L; de Jong, M D; Osterhaus, A D M E; Papa, A; Rimstad, E; Valarcher, J-F; Kuiken, T
Companion animals comprise a wide variety of species, including dogs, cats, horses, ferrets, guinea pigs, reptiles, birds and ornamental fish, as well as food production animal species, such as domestic pigs, kept as companion animals. Despite their prominent place in human society, little is known about the role of companion animals as sources of viruses for people and food production animals. Therefore, we reviewed the literature for accounts of infections of companion animals by zoonotic viruses and viruses of food production animals, and prioritized these viruses in terms of human health and economic importance. In total, 138 virus species reportedly capable of infecting companion animals were of concern for human and food production animal health: 59 of these viruses were infectious for human beings, 135 were infectious for food production mammals and birds, and 22 were infectious for food production fishes. Viruses of highest concern for human health included hantaviruses, Tahyna virus, rabies virus, West Nile virus, tick-borne encephalitis virus, Crimean-Congo haemorrhagic fever virus, Aichi virus, European bat lyssavirus, hepatitis E virus, cowpox virus, G5 rotavirus, influenza A virus and lymphocytic choriomeningitis virus. Viruses of highest concern for food production mammals and birds included bluetongue virus, African swine fever virus, foot-and-mouth disease virus, lumpy skin disease virus, Rift Valley fever virus, porcine circovirus, classical swine fever virus, equine herpesvirus 9, peste des petits ruminants virus and equine infectious anaemia virus. Viruses of highest concern for food production fishes included cyprinid herpesvirus 3 (koi herpesvirus), viral haemorrhagic septicaemia virus and infectious pancreatic necrosis virus. Of particular concern as sources of zoonotic or food production animal viruses were domestic carnivores, rodents and food production animals kept as companion animals. The current list of viruses provides an objective
Nannini, D; Calistri, P; Giovannini, A; Di Ventura, M; Cafiero, M A; Ferrari, G; Santucci, U; Caporale, V
Transhumance, or seasonal grazing, in central Italy is a husbandry practice that is over two thousand years old. It involves the seasonal movement of sheep, goats and cattle from the southern lowlands of mainly the Puglia and Lazio regions, to summer pastures in the mountains of Abruzzo and Molise. Bluetongue (BT) made its appearance in Italy in 2000. In the early summer of 2001, disease was present in three regions: Sardinia, Sicily and Calabria. Neither an effective surveillance system nor a vaccination campaign had been implemented. Movement of ruminants to the disease-free regions of Abruzzo and Molise was therefore banned. The Italian Veterinary Services had to meet the challenge of the movement of ruminants from surveillance to disease-free zones, given the impossibility of stopping transhumance. The General Directorate of Veterinary Public Health, Food and Nutrition of the Ministry of Health developed a plan for both the Puglia and Abruzzo regions based on serological, virological and entomological surveillance. The plan was implemented between May and June 2001 when 7,000 animals moved from the Puglia surveillance zone to the infection-free summer pastures. In the early summer of 2002, eight regions were infected (Sardinia, Sicily, Calabria, Basilicata, Puglia, Campania, Lazio and Tuscany). Simultaneously, a nationwide surveillance system and a vaccination campaign, were implemented in infected regions. In the provinces where vaccination was compulsory, deviation from the animal movement ban was allowed if at least 80% of susceptible stock had been vaccinated. However, this objective was not achieved in the provinces of Rome and Viterbo (Lazio) where a large transhumant population was present and where sporadic virus circulation had been detected. A specific control plan to allow transhumance from Lazio to Abruzzo, Marche and Umbria was designed and implemented to increase the number of animals that could be moved. Between May and June 2002, authorisation
Brodie, Scott J.; Wilson, William C.; O’Hearn, Patricia M.; Muthui, David; Diem, Kurt; Pearson, Leonard D.
We investigated the effects of pharmacological and lentivirus-induced immunosuppression on bluetongue virus (BTV) pathogenesis as a mechanism for virus persistence and induction of clinical disease. Immunologically normal and immunosuppressed sheep were infected subcutaneously with BTV serotype 3 (BTV-3), a foreign isolate with unknown pathogenicity in North American livestock, and with North American serotype 11 (BTV-11). Erythrocyte-associated BTV RNA was detected earlier and at greater con...
Full Text Available Mathematical formulations for the basic reproduction ratio (R(0 exist for several vector-borne diseases. Generally, these are based on models of one-host, one-vector systems or two-host, one-vector systems. For many vector borne diseases, however, two or more vector species often co-occur and, therefore, there is a need for more complex formulations. Here we derive a two-host, two-vector formulation for the R(0 of bluetongue, a vector-borne infection of ruminants that can have serious economic consequences; since 1998 for example, it has led to the deaths of well over 1 million sheep in Europe alone. We illustrate our results by considering the situation in South Africa, where there are two major hosts (sheep, cattle and two vector species with differing ecologies and competencies as vectors, for which good data exist. We investigate the effects on R(0 of differences in vector abundance, vector competence and vector host preference between vector species. Our results indicate that R(0 can be underestimated if we assume that there is only one vector transmitting the infection (when there are in fact two or more and/or vector host preferences are overlooked (unless the preferred host is less beneficial or more abundant. The two-host, one-vector formula provides a good approximation when the level of cross-infection between vector species is very small. As this approaches the level of intraspecies infection, a combination of the two-host, one-vector R(0 for each vector species becomes a better estimate. Otherwise, particularly when the level of cross-infection is high, the two-host, two-vector formula is required for accurate estimation of R(0. Our results are equally relevant to Europe, where at least two vector species, which co-occur in parts of the south, have been implicated in the recent epizootic of bluetongue.
Full Text Available François Claine, Damien Coupeau, Laetitia Wiggers, Benoît Muylkens, Nathalie Kirschvink Veterinary Department, Faculty of Sciences, Namur Research Institute for Life Sciences (NARILIS, University of Namur (UNamur, Namur, Belgium Abstract: In 2011, European ruminant flocks were infected by Schmallenberg virus (SBV leading to transient disease in adult cattle but abortions and congenital deformities in calves, lambs, and goat kids. SBV belonging to the Simbu serogroup (family Bunyaviridae and genus Orthobunyavirus was first discovered in the same region where bluetongue virus serotype 8 (BTV-8 emerged 5 years before. Both viruses are transmitted by biting midges (Culicoides spp. and share several similarities. This paper describes the current knowledge of temporal and geographical spread, molecular virology, transmission and susceptible species, clinical signs, diagnosis, prevention and control, impact on ruminant health, and productivity of SBV infection in Europe, and compares SBV infection with BTV-8 infection in ruminants. Keywords: Schmallenberg virus, Europe, ruminants, review
Full Text Available Pig farms: reservoirs of vectors of Bluetongue and Schmallenberg viruses?. Bluetongue (BT is a vector-borne disease that affects domestic and wild ruminants. Since its recent outbreak in northern Europe, this viral disease has caused considerable economic losses. The biological vectors of the bluetongue virus are biting midges belonging to the genus Culicoides (Diptera: Ceratopogonidae. Several light trapping campaigns targeting these adult midges have been previously conducted in Belgium within cattle and sheep farms, but none have been performed inside pig farms. This study therefore aims to assess, using light traps, the levels of Culicoides populations that may have been present inside two Belgian pig farms during the fall and winter of 2008. The presence of (potential Culicoides vector species was demonstrated inside the pig buildings during the fall: 8 and 749 specimens belonging to 2 and 7 species were respectively trapped inside the pigsties, with the majority being Obsoletus complex females. The opening up of the buildings seemed to strongly influence their presence. Observation of the females' nutritional status suggests that these midges were likely to have fed or to have laid eggs inside the pig farms, despite the fact that pig's blood could not be identified in the abdomen of engorged females and that pig manure did not reveal the presence of larvae. Pigs could thus be involved in the maintenance of potential vector species populations of the BT virus, or of the new Schmallenberg virus.
Four kinds of RNA viruses, Bluetongue virus (BT), Bovine Virus Diarrhea-Mucosal Disease virus (BVD·MD), Bovine Respiratory Syncytial virus (RS), Vesicular Stmatitis virus (VS), were subjected to various doses of gamma irradiation to determine the lethal doses. The D10 values, which are the dose necessary to decimally reduce infectivity, ranged from 1.5 to 3.4 kGy under frozen condition at dry-ice temperature, and they increased to 2.6 to 5.0 kGy under frozen condition at dry-ice temperature. Serum neutralzing antibody titer of Infectious Bovine Rhinotracheitis (IBR) was not adversely changed by the exposure to 36 kGy of gamma-rays under frozen condition. Analysis of electrophoresis patterns of the bovine serum also reveales that the serum proteins were not remarkably affected, even when exposed to 36 kGy of gamma radiation under frozen condition. The results suggested that gamma irradiation under frozen condition is an effective means for inactivating both DNA and RNA viruses without adversely affecting serum proteins and neutralizing antibody titer. (author)
Guis, Hélène; Tran, Annelise; Mauny, Frédéric; Baldet, Thierry; Barragué, Bruno; Gerbier, Guillaume; Viel, Jean-François; Roger, François; de La Rocque, Stéphane
Landscape ecology is seldom used in epidemiology. The aim of this study is to assess the possible improvements that can be derived from the use of landscape approaches on several scales when exploring local differences in disease distribution, using bluetongue (BT) in Corsica as an example. The environment of BT-free and BT-infected sheep farms is described on a fine scale, using high resolution satellite images and a digital elevation model. Land-coverage is characterised by classifying the satellite image. Landscape metrics are calculated to quantify the number, diversity, length of edge and connectance of vegetation patches. The environment is described for three sizes of buffers around the farms. The models are tested with and without landscape metrics to see if such metrics improve the models. Internal and external validation of the models is performed and the relative impact of scale versus variables on the discriminatory ability of the models is explored. Results show that for all scales and irrespective of the number of parameters included, models with landscape metrics perform better than those without. The 1-km buffer model combines both the best scale of application and the best set of variables. It has a good discriminating ability and good sensitivity and specificity. PMID:20422549
... Vector-Borne Diseases (DVBD) NCEZID Share Compartir Heartland virus On this Page What is Heartland virus? How ... Do I Need to Know? What is Heartland virus? Heartland virus belongs to a family of viruses ...
Napp, S.; Allepuz, A.; Purse, B. V.; Casal, J.; García-Bocanegra, I.; Burgin, L. E.; Searle, K. R.
Andalusia (Southern Spain) is considered one of the main routes of introduction of bluetongue virus (BTV) into Europe, evidenced by a devastating epidemic caused by BTV-1 in 2007. Understanding the pattern and the drivers of BTV-1 spread in Andalusia is critical for effective detection and control of future epidemics. A long-standing metric for quantifying the behaviour of infectious diseases is the case-reproduction ratio (Rt), defined as the average number of secondary cases arising from a single infected case at time t (for t>0). Here we apply a method using epidemic trees to estimate the between-herd case reproduction ratio directly from epidemic data allowing the spatial and temporal variability in transmission to be described. We then relate this variability to predictors describing the hosts, vectors and the environment to better understand why the epidemic spread more quickly in some regions or periods. The Rt value for the BTV-1 epidemic in Andalusia peaked in July at 4.6, at the start of the epidemic, then decreased to 2.2 by August, dropped below 1 by September (0.8), and by October it had decreased to 0.02. BTV spread was the consequence of both local transmission within established disease foci and BTV expansion to distant new areas (i.e. new foci), which resulted in a high variability in BTV transmission, not only among different areas, but particularly through time, which suggests that general control measures applied at broad spatial scales are unlikely to be effective. This high variability through time was probably due to the impact of temperature on BTV transmission, as evidenced by a reduction in the value of Rt by 0.0041 for every unit increase (day) in the extrinsic incubation period (EIP), which is itself directly dependent on temperature. Moreover, within the range of values at which BTV-1 transmission occurred in Andalusia (20.6°C to 29.5°C) there was a positive correlation between temperature and Rt values, although the relationship was
Full Text Available Andalusia (Southern Spain is considered one of the main routes of introduction of bluetongue virus (BTV into Europe, evidenced by a devastating epidemic caused by BTV-1 in 2007. Understanding the pattern and the drivers of BTV-1 spread in Andalusia is critical for effective detection and control of future epidemics. A long-standing metric for quantifying the behaviour of infectious diseases is the case-reproduction ratio (Rt, defined as the average number of secondary cases arising from a single infected case at time t (for t>0. Here we apply a method using epidemic trees to estimate the between-herd case reproduction ratio directly from epidemic data allowing the spatial and temporal variability in transmission to be described. We then relate this variability to predictors describing the hosts, vectors and the environment to better understand why the epidemic spread more quickly in some regions or periods. The Rt value for the BTV-1 epidemic in Andalusia peaked in July at 4.6, at the start of the epidemic, then decreased to 2.2 by August, dropped below 1 by September (0.8, and by October it had decreased to 0.02. BTV spread was the consequence of both local transmission within established disease foci and BTV expansion to distant new areas (i.e. new foci, which resulted in a high variability in BTV transmission, not only among different areas, but particularly through time, which suggests that general control measures applied at broad spatial scales are unlikely to be effective. This high variability through time was probably due to the impact of temperature on BTV transmission, as evidenced by a reduction in the value of Rt by 0.0041 for every unit increase (day in the extrinsic incubation period (EIP, which is itself directly dependent on temperature. Moreover, within the range of values at which BTV-1 transmission occurred in Andalusia (20.6°C to 29.5°C there was a positive correlation between temperature and Rt values, although the
Meiswinkel, R; Labuschagne, K; Baylis, M; Mellor, P S
Blacklight traps were used to collect Culicoides biting midges weekly between September 1996 and August 1998 at 40 sites distributed equidistantly across South Africa. The seasonal and geographic prevalences of 86 species of Culicoides were elucidated simultaneously, and included C. imicola Kieffer and C. bolitinos Meiswinkel the principal vectors of bluetongue (BT) and African horse sickness (AHS) in the region. These two species were amongst the most prevalent Culicoides to be found and, together, comprised >50% of the more than three million biting midges captured. The data are presented as coloured matrices, and are transformed also into inverse distance weighting (IDW) interpolative maps. The data reveal that the prevalence of each vector is somewhat fractured and it is posited that this is (in part) due to significant differences in their respective breeding habitats. The results illustrate also that the presence of multiple vectors (in any region of the world) will complicate both the epidemiology of the orbiviral diseases they transmit and the formulation of rational livestock movement and disease control strategies. This is especially true for southern Europe where the recent devastating cycle of BT has been shown to involve at least three vectors. Finally, the influence that man has on the development of large foci of vector Culicoides around livestock may be less important than previously suggested but must be investigated further. PMID:20419682
Jemma L Geoghegan
Full Text Available Arthropod-borne viruses are a major cause of emerging disease with significant public health and economic impacts. However, the factors that determine their activity and seasonality are not well understood. In Australia, a network of sentinel cattle herds is used to monitor the distribution of several such viruses and to define virus-free regions. Herein, we utilize these serological data to describe the seasonality, and its drivers, of three economically important animal arboviruses: bluetongue virus, Akabane virus and bovine ephemeral fever virus. Through epidemiological time-series analyses of sero-surveillance data of 180 sentinel herds between 2004-2012, we compared seasonal parameters across latitudes, ranging from the tropical north (-10°S to the more temperate south (-40°S. This analysis revealed marked differences in seasonality between distinct geographic regions and climates: seasonality was most pronounced in southern regions and gradually decreased as latitude decreased toward the Equator. Further, we show that both the timing of epidemics and the average number of seroconversions have a strong geographical component, which likely reflect patterns of vector abundance through co-varying climatic factors, especially temperature and rainfall. Notably, despite their differences in biology, including insect vector species, all three viruses exhibited very similar seasonality. By revealing the factors that shape spatial and temporal distributions, our study provides a more complete understanding of arbovirus seasonality that will enable better risk predictions.
Wright, Isabella Maria
Alpacas were first introduced into South Africa during the year 2000. They are valuable because of the fine quality wool they produce which has much better insulation properties than that of merino wool fibres. Alpacas are also used to act as guards of sheep herds against predators. During 2008, blood samples from an alpaca that died acutely with severe lung oedema, respiratory distress and froth exuding from the nose were received at Elsenburg Veterinary Laboratory. The alp...
Bøtner, Anette; Oura, Chris; Saegerman, Claude; MacLachlan, James; Van Rijn, Piet; Sharp, James Michael; Stegeman, Jan Arend; Dhollander, Sofie; Gervelmeyer, Andrea; Lefebvre, Diane
insemination or mating, so there is no subsequent risk of transplacental infection of their offspring. Furthermore, pregnant animals are effectively restricted in their movement. More research is needed to determine whether oral transmission and/or transmission through embryo transfer are more likely to occur...... established by the Animal Health and Welfare Panel. Currently, three special features can be assigned to BTV-8, which are the ability to cause serious disease in cattle and goats, the ability to be transmitted transplacentally, and the ability to contaminate semen. The transplacental transmission and the...... contamination of semen are also observed for several serotypes of modified live virus (MLV) vaccines and for some cell culture/egg passaged strains. These two features may have an impact on the epidemiology of the disease, since they may increase the ability of BTV-8 to survive the winter period, for example...
Wilson, W C; Ruder, M G; Jasperson, D; Smith, T P L; Naraghi-Arani, P; Lenhoff, R; Stallknecht, D E; Valdivia-Granda, W A; Sheoran, D
Epizootic hemorrhagic disease virus (EHDV) is an orbivirus of the Reoviridae family that has significant impact on wild and captive white-tailed deer. Although closely related to bluetongue virus that can cause disease in sheep and cattle, North American EHDV historically has not been associated with disease in cattle or sheep. Severe disease in cattle has been reported with other EHDV strains from East Asia and the Middle East. To understand the potential role of viral genetics in the epidemiology of epizootic hemorrhagic disease, a molecular characterization of North American EHDV strains from 1955 to 2012 was conducted via conventional phylogenetic analysis and a new classification approach using motif fingerprint patterns. Overall, this study indicates that the genetic make-up of EHDV populations in North America have slowly evolved over time. The data also suggested limited reassortment events between serotypes 1 and 2 and introduces a new analysis tool for more detailed sequence pattern analysis. PMID:27107856
Fajardo, Teodoro; Sung, Po-Yu; Roy, Polly
Bluetongue virus (BTV) causes hemorrhagic disease in economically important livestock. The BTV genome is organized into ten discrete double-stranded RNA molecules (S1-S10) which have been suggested to follow a sequential packaging pathway from smallest to largest segment during virus capsid assembly. To substantiate and extend these studies, we have investigated the RNA sorting and packaging mechanisms with a new experimental approach using inhibitory oligonucleotides. Putative packaging signals present in the 3'untranslated regions of BTV segments were targeted by a number of nuclease resistant oligoribonucleotides (ORNs) and their effects on virus replication in cell culture were assessed. ORNs complementary to the 3' UTR of BTV RNAs significantly inhibited virus replication without affecting protein synthesis. Same ORNs were found to inhibit complex formation when added to a novel RNA-RNA interaction assay which measured the formation of supramolecular complexes between and among different RNA segments. ORNs targeting the 3'UTR of BTV segment 10, the smallest RNA segment, were shown to be the most potent and deletions or substitution mutations of the targeted sequences diminished the RNA complexes and abolished the recovery of viable viruses using reverse genetics. Cell-free capsid assembly/RNA packaging assay also confirmed that the inhibitory ORNs could interfere with RNA packaging and further substitution mutations within the putative RNA packaging sequence have identified the recognition sequence concerned. Exchange of 3'UTR between segments have further demonstrated that RNA recognition was segment specific, most likely acting as part of the secondary structure of the entire genomic segment. Our data confirm that genome packaging in this segmented dsRNA virus occurs via the formation of supramolecular complexes formed by the interaction of specific sequences located in the 3' UTRs. Additionally, the inhibition of packaging in-trans with inhibitory ORNs
Sedda, Luigi; Brown, Heidi E; Purse, Bethan V; Burgin, Laura; Gloster, John; Rogers, David J
The 2006 bluetongue (BT) outbreak in northwestern Europe had devastating effects on cattle and sheep in that intensively farmed area. The role of wind in disease spread, through its effect on Culicoides dispersal, is still uncertain, and remains unquantified. We examine here the relationship between farm-level infection dates and wind speed and direction within the framework of a novel model involving both mechanistic and stochastic steps. We consider wind as both a carrier of host semio-chemicals, to which midges might respond by upwind flight, and as a transporter of the midges themselves, in a more or less downwind direction. For completeness, we also consider midge movement independent of wind and various combinations of upwind, downwind and random movements. Using stochastic simulation, we are able to explain infection onset at 94 per cent of the 2025 affected farms. We conclude that 54 per cent of outbreaks occurred through (presumably midge) movement of infections over distances of no more than 5 km, 92 per cent over distances of no more than 31 km and only 2 per cent over any greater distances. The modal value for all infections combined is less than 1 km. Our analysis suggests that previous claims for a higher frequency of long-distance infections are unfounded. We suggest that many apparent long-distance infections resulted from sequences of shorter-range infections; a 'stepping stone' effect. Our analysis also found that downwind movement (the only sort so far considered in explanations of BT epidemics) is responsible for only 39 per cent of all infections, and highlights the effective contribution to disease spread of upwind midge movement, which accounted for 38 per cent of all infections. The importance of midge flight speed is also investigated. Within the same model framework, lower midge active flight speed (of 0.13 rather than 0.5 m s(-1)) reduced virtually to zero the role of upwind movement, mainly because modelled wind speeds in the area
Kumar, Amit; Yogisharadhya, Revanaiah; Venkatesan, Gnanavel; Bhanuprakash, Veerakyathappa; Shivachandra, Sathish Bhadravati
Buffalopox virus, a zoonotic Indian vaccinia-like virus, is responsible for contagious disease affecting mainly buffaloes, cattle and humans. H3L gene, encoding for an immunodominant major envelope protein of intracellular mature virion of orthopoxviruses, is highly conserved and found to elicit neutralizing antibodies. Therefore in the present study, the immunogenicity and protective efficacy of the recombinant H3L protein of buffalopox virus in laboratory animal models has been evaluated. A partial H3L gene encoding for the C-terminal truncated ectodomain of H3L protein (1M to I280) of BPXV-Vij/96 strain was cloned, over-expressed and purified as histidine-tagged fusion protein (50 kDa) from Escherichia coli using Ni-NTA affinity chromatography. The purified rH3L protein was further used for active immunization of guinea pig (250 μg/dose) and adult mice (10 μg and 50 μg/dose) with or without adjuvants (alum, Freund's Complete Adjuvant and CpG). Subsequently, a gradual increase in antigen specific serum IgG as well as neutralizing antibody titres measured by using indirect-ELISA and serum neutralization test respectively, was noted in both guinea pigs and mouse models. Suckling mice immunized passively with anti-H3L serum showed 80% pre-exposure prophylaxis upon challenge with virulent buffalopox virus strain. An indirect-ELISA based on rH3L protein showed no cross-reactivity with hyperimmune sera against sheeppox virus (SPPV), goatpox virus (GTPV), orf virus (ORFV), foot- and- mouth disease virus (FMDV), peste des petits ruminants virus (PPRV) and bluetongue virus (BTV) during the course of study. The study highlights the potential utility of rH3L protein as a safer prophylactic and diagnostic reagent for buffalopox. PMID:26723250
... Gaines, PhD, MPH, MA, CHES Differentiating Chikungunya From Dengue: A Clinical Challenge For Travelers CDC Travelers' Health Chikungunya Virus Home Prevention Transmission Symptoms & Treatment Geographic Distribution Chikungunya virus in ...
Zika is a virus that is spread mostly by mosquitoes. A pregnant mother can pass it to ... through blood transfusions. There have been outbreaks of Zika virus in the United States, Africa, Southeast Asia, ...
Chikungunya virus infection; Chikungunya ... Where Chikungunya is found Before 2013, the virus was found in Africa, Asia, Europe, and the Indian and Pacific oceans. In late 2013, outbreaks occurred for the first time in the ...
Enteric cytopathic human orphan (ECHO) viruses are a group of viruses that lead to gastrointestinal infection and skin rashes. ... Echovirus is one of several families of viruses that affect the ... are common. In the United States, they are most common in ...
... Zika Virus | See Q&A —June 21, 2016 Zika Virus Protein Could Be Vaccine Target —May 19, 2016 Research Conducted and Supported by the National Institutes of Health (NIH) in Addressing Zika Virus Disease. Testimony before the House Democratic Steering ...
Abramjan, Andran; Bauerová, Anna; Somerová, Barbora; Frynta, Daniel
Blue-tongued skinks of the genus Tiliqua (Scincidae) are characterized by their large blue melanin-pigmented tongues, often displayed during open-mouth threats, when the animal feels endangered. It is not clear whether this unusual coloration is a direct anti-predation adaptation or it may rather serve intraspecific communication, as ultraviolet-blue color is a frequent visual signal in a number of lizard species. We used spectrophotometry and visual modeling to compare blue tongues of Tiliqua gigas with tongues and skin coloration of other lizard species, and to examine their appearance through the eyes of both the conspecifics and avian predators. Our results show that (1) the tongue coloration is probably not substantially influenced by the amount of melanin in the skin, (2) lingual and oral tissues are UV-reflective in general, with blue colored tongues having chromatic qualities similar to UV-blue skin patches of other lizard species, (3) UV-blue tongues are more conspicuous than pink tongues, especially in the visual model of conspecifics. We hypothesize that blue tongues may possibly serve as a semantic (honest) signal analogous to UV-blue skin patches of other lizard species due to greater UV-bias in the vision of diurnal lizards. Regarding the social behavior and high aggressiveness in Tiliqua and their relatives, such signal might serve, e.g., in intraspecific long-distance communication between conspecifics in order to avoid aggression, and its anti-predation effect may only be a secondary function (exaptation).
Computer viruses are small software programs that are designed to spread from one computerto another and to interfere with computer operation.A virus might delete data on your computer,use your e-mail program to spread itself to othercomputers,or even erase everything on your hard disk.Viruses are most easily spread by attach-ments in e-mail messages or instant messaging messages.That is why it is essential that you never
World-wide there are at least 24 serotypes of bluetongue virus (BTV), a complex non-enveloped virus in the family Reoviridae, genus Orbivirus. Bluetongue (BT) is an arthropod-borne disease of cattle, sheep, goats, and deer and is transmitted by Culicoides biting midges. In 2006, bluetongue serotype ...
Denning, Peter J.
The worm, Trojan horse, bacterium, and virus are destructive programs that attack information stored in a computer's memory. Virus programs, which propagate by incorporating copies of themselves into other programs, are a growing menace in the late-1980s world of unprotected, networked workstations and personal computers. Limited immunity is offered by memory protection hardware, digitally authenticated object programs,and antibody programs that kill specific viruses. Additional immunity can be gained from the practice of digital hygiene, primarily the refusal to use software from untrusted sources. Full immunity requires attention in a social dimension, the accountability of programmers.
Phillips, Jennan A; Neyland, Anavernyel
Zika virus (ZIKV) infections are the latest global public health emergency. Occupational health nurses can protect society by educating workers, women of childbearing age, and others traveling in ZIKV-infected areas about prevention strategies. PMID:27411846
... A - Z Index SMALLPOX FACT SHEET The Live Virus Smallpox Vaccine The vaccinia virus is the "live ... it cannot cause smallpox. What is a "live virus" vaccine? A "live virus" vaccine is a vaccine ...
Ponder, Tim, Comp.; Ropog, Marty, Comp.; Keating, Joseph, Comp.
This document provides general information on computer viruses, how to help protect a computer network from them, measures to take if a computer becomes infected. Highlights include the origins of computer viruses; virus contraction; a description of some common virus types (File Virus, Boot Sector/Partition Table Viruses, Trojan Horses, and…
Zwart, Lizahn; Potgieter, Christiaan A; Clift, Sarah J; van Staden, Vida
African horse sickness is a serious equid disease caused by the orbivirus African horse sickness virus (AHSV). The virus has ten double-stranded RNA genome segments encoding seven structural and three non-structural proteins. Recently, an additional protein was predicted to be encoded by genome segment 9 (Seg-9), which also encodes VP6, of most orbiviruses. This has since been confirmed in bluetongue virus and Great Island virus, and the non-structural protein was named NS4. In this study, in silico analysis of AHSV Seg-9 sequences revealed the existence of two main types of AHSV NS4, designated NS4-I and NS4-II, with different lengths and amino acid sequences. The AHSV NS4 coding sequences were in the +1 reading frame relative to that of VP6. Both types of AHSV NS4 were expressed in cultured mammalian cells, with sizes close to the predicted 17-20 kDa. Fluorescence microscopy of these cells revealed a dual cytoplasmic and nuclear, but not nucleolar, distribution that was very similar for NS4-I and NS4-II. Immunohistochemistry on heart, spleen, and lung tissues from AHSV-infected horses showed that NS4 occurs in microvascular endothelial cells and mononuclear phagocytes in all of these tissues, localising to the both the cytoplasm and the nucleus. Interestingly, NS4 was also detected in stellate-shaped dendritic macrophage-like cells with long cytoplasmic processes in the red pulp of the spleen. Finally, nucleic acid protection assays using bacterially expressed recombinant AHSV NS4 showed that both types of AHSV NS4 bind dsDNA, but not dsRNA. Further studies will be required to determine the exact function of AHSV NS4 during viral replication. PMID:25915516
Anusha Rangare Lakshman
Full Text Available The disease Ebola takes its name from the Ebola River situated near a village in the Democratic Republic of Congo, where the disease first appeared in 1976. It is caused by a virus from the Filoviridae family (filovirus. The present outbreak of Ebola Virus Disease (EVD concerns four countries in West Africa, namely Guinea, Liberia, Sierra Leone and Nigeria till date. Further to widespread transmission of the disease, it has been declared as a Public Health Emergency of International Concern by the World Health Organisation on 8 August 2014. As of 4 August 2014, countries have reported 1,711 cases (1,070 confirmed, 436 probable, 205 suspect, including 932 deaths. This review paper enlightens about the awareness of Ebola virus and its preventive measures. [Archives Medical Review Journal 2015; 24(3.000: 296-305
Leite, Juliana A.; Drumond, Betânia P.; Trindade, Giliane S; Zélia I P Lobato; da Fonseca, Flávio G.; dos Santos, João R.; Madureira, Marieta C.; Guedes, Maria I.M.C.; Ferreira, Jaqueline M. S.; Bonjardim, Cláudio A.; Ferreira, Paulo C. P.; Kroon, Erna G.
Passatempo virus was isolated during a zoonotic outbreak. Biologic features and molecular characterization of hemagglutinin, thymidine kinase, and vaccinia growth factor genes suggested a vaccinia virus infection, which strengthens the idea of the reemergence and circulation of vaccinia virus in Brazil. Molecular polymorphisms indicated that Passatempo virus is a different isolate.
Salim Mattar V.
Full Text Available Bunyaviruses are RNA viruses that affect animals and plants; they have five genera and four of them affect humans: Orthobunyavirus, Nairovirus, Phlebovirus and Hantavirus. All of them are Arbovirus, except Hantavirus. The Orthobunyaviruses comprise Oropouche, Tahyna, La Crosse virus, California encephalitis virus and Heartland virus recently discovered (1. Except for Heartland virus which is transmitted by ticks of the genus Amblyoma, these Phleboviruses have as vectors mosquitoes, which bite small mammals which are able to be as reservoirs amplifiers.
Roossinck, Marilyn J; Martin, Darren P; Roumagnac, Philippe
In recent years plant viruses have been detected from many environments, including domestic and wild plants and interfaces between these systems-aquatic sources, feces of various animals, and insects. A variety of methods have been employed to study plant virus biodiversity, including enrichment for virus-like particles or virus-specific RNA or DNA, or the extraction of total nucleic acids, followed by next-generation deep sequencing and bioinformatic analyses. All of the methods have some shortcomings, but taken together these studies reveal our surprising lack of knowledge about plant viruses and point to the need for more comprehensive studies. In addition, many new viruses have been discovered, with most virus infections in wild plants appearing asymptomatic, suggesting that virus disease may be a byproduct of domestication. For plant pathologists these studies are providing useful tools to detect viruses, and perhaps to predict future problems that could threaten cultivated plants. PMID:26056847
Musso, Didier; Gubler, Duane J
Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) in the genus Flavivirus and the family Flaviviridae. ZIKV was first isolated from a nonhuman primate in 1947 and from mosquitoes in 1948 in Africa, and ZIKV infections in humans were sporadic for half a century before emerging in the Pacific and the Americas. ZIKV is usually transmitted by the bite of infected mosquitoes. The clinical presentation of Zika fever is nonspecific and can be misdiagnosed as other infectious diseases, especially those due to arboviruses such as dengue and chikungunya. ZIKV infection was associated with only mild illness prior to the large French Polynesian outbreak in 2013 and 2014, when severe neurological complications were reported, and the emergence in Brazil of a dramatic increase in severe congenital malformations (microcephaly) suspected to be associated with ZIKV. Laboratory diagnosis of Zika fever relies on virus isolation or detection of ZIKV-specific RNA. Serological diagnosis is complicated by cross-reactivity among members of the Flavivirus genus. The adaptation of ZIKV to an urban cycle involving humans and domestic mosquito vectors in tropical areas where dengue is endemic suggests that the incidence of ZIKV infections may be underestimated. There is a high potential for ZIKV emergence in urban centers in the tropics that are infested with competent mosquito vectors such as Aedes aegypti and Aedes albopictus. PMID:27029595
Discusses the early history and current proliferation of computer viruses that occur on Macintosh and DOS personal computers, mentions virus detection programs, and offers suggestions for how libraries can protect themselves and their users from damage by computer viruses. (LRW)
Marschang, Rachel E.
A large number of viruses have been described in many different reptiles. These viruses include arboviruses that primarily infect mammals or birds as well as viruses that are specific for reptiles. Interest in arboviruses infecting reptiles has mainly focused on the role reptiles may play in the epidemiology of these viruses, especially over winter. Interest in reptile specific viruses has concentrated on both their importance for reptile medicine as well as virus taxonomy and evolution. The ...
Guangxiang; George; Luo; Jing-hsiung; James; Ou
<正>This special issue of the journal is dedicated to the important topic of oncogenic viruses and cancer.It contains seven review articles covering all known oncogenic viruses except for human T-lymphotropic virus type1(HTLV-1).These review articles are contributed by experts on specific viruses and their associated human cancers.Viruses account for about 20%of total human cancer cases.Although many viruses can cause various tumors in animals,only seven of them
Smith, S; Danganan, L; Tammero, L; Lenhoff, R; Naraghi-arani, P; Hindson, B
Lawrence Livermore National Laboratory (LLNL), in collaboration with the Department of Homeland Security (DHS) and the United States Department of Agriculture (USDA), Animal and Plant Health Inspection Services (APHIS) has developed advanced rapid diagnostics that may be used within the National Animal Health Laboratory Network (NAHLN), the National Veterinary Services Laboratory (Ames, Iowa) and the Plum Island Animal Disease Center (PIADC). This effort has the potential to improve our nation's ability to discriminate between foreign animal diseases and those that are endemic using a single assay, thereby increasing our ability to protect animal populations of high economic importance in the United States. Under 2005 DHS funding we have developed multiplexed (MUX) nucleic-acid-based PCR assays that combine foot-and-mouth disease virus (FMDV) detection with rule-out tests for two other foreign animal diseases Vesicular Exanthema of Swine (VESV) and Swine Vesicular Disease (SVD) and four other domestic viral diseases Bovine Viral Diarrhea Virus (BVDV), Bovine Herpes Virus 1 (BHV-1 or Infectious Bovine Rhinotracheitus IBR), Bluetongue virus (BTV) and Parapox virus complex (which includes Bovine Papular Stomatitis Virus BPSV, Orf of sheep, and Pseudocowpox). Under 2006 funding we have developed a Multiplexed PCR [MUX] porcine assay for detection of FMDV with rule out tests for VESV and SVD foreign animal diseases in addition to one other domestic vesicular animal disease vesicular stomatitis virus (VSV) and one domestic animal disease of swine porcine reproductive and respiratory syndrome (PRRS). We have also developed a MUX bovine assay for detection of FMDV with rule out tests for the two bovine foreign animal diseases malignant catarrhal fever (MCF), rinderpest virus (RPV) and the domestic diseases vesicular stomatitis virus (VSV), bovine viral diarrhea virus (BVDV), infectious bovine rhinotracheitus virus (BHV-1), bluetongue virus (BTV), and the Parapox
J. Snyder; B. Wiedenheft; M. Lavin; F. Roberto; J. Spuhler; A. Ortmann; T. Douglas; M. Young
Viruses are the largest reservoir of genetic material on the planet, yet little is known about the population dynamics of any virus within its natural environment. Over a 2-year period, we monitored the diversity of two archaeal viruses found in hot springs within Yellowstone National Park (YNP). Both temporal phylogeny and neutral biodiversity models reveal that virus diversity in these local environments is not being maintained by mutation but rather by high rates of immigration from a globally distributed metacommunity. These results indicate that geographically isolated hot springs are readily able to exchange viruses. The importance of virus movement is supported by the detection of virus particles in air samples collected over YNP hot springs and by their detection in metacommunity sequencing projects conducted in the Sargasso Sea. Rapid rates of virus movement are not expected to be unique to these archaeal viruses but rather a common feature among virus metacommunities. The finding that virus immigration rather than mutation can dominate community structure has significant implications for understanding virus circulation and the role that viruses play in ecology and evolution by providing a reservoir of mobile genetic material.
De Regge, Nick; Madder, Maxime; Deblauwe, Isra; Losson, Bertrand; Fassotte, Christiane; Demeulemeester, Julie; Smeets, François; Tomme, Marie; Cay, Ann Brigitte
Indigenous Culicoides biting midges are suggested to be putative vectors for the recently emerged Schmallenberg virus (SBV) based on SBV RNA detection in field-caught midges. Furthermore, SBV replication and dissemination has been evidenced in C. sonorensis under laboratory conditions. After SBV had been detected in Culicoides biting midges from Belgium in August 2011, it spread all over the country by the end of 2011, as evidenced by very high between-herd seroprevalence rates in sheep and cattle. This study investigated if a renewed SBV circulation in midges occurred in 2012 in the context of high seroprevalence in the animal host population and evaluated if a recently proposed realtime RT-PCR approach that is meant to allow assessing the vector competence of Culicoides for SBV and bluetongue virus under laboratory conditions was applicable to field-caught midges. Therefore midges caught with 12 OVI traps in four different regions in Belgium between May and November 2012, were morphologically identified, age graded, pooled and tested for the presence of SBV RNA by realtime RT-PCR. The results demonstrate that although no SBV could be detected in nulliparous midges caught in May 2012, a renewed but short lived circulation of SBV in parous midges belonging to the subgenus Avaritia occured in August 2012 at all four regions. The infection prevalence reached up to 2.86% in the south of Belgium, the region where a lower seroprevalence was found at the end of 2011 than in the rest of the country. Furthermore, a frequency analysis of the Ct values obtained for 31 SBV-S segment positive pools of Avaritia midges showed a clear bimodal distribution with peaks of Ct values between 21–24 and 33–36. This closely resembles the laboratory results obtained for SBV infection of C. sonorensis and implicates indigenous midges belonging to the subgenus Avaritia as competent vectors for SBV. PMID:24466312
［1］Suzuki, N., Sugawara, M., Kusano, T. et al., Immunodetection of rice dwarf phytoreoviral protein in both insect and plant hosts, Virology, 1994, 202: 41.［2］Omura, T., Ishikawa, K., Hirano, H. et al., The outer capid protein of rice dwarf virus is encoded by genome segment S8, J. Gen. Virol., 1989, 70: 2759.［3］Lu, G. Y., Zhou, Z. H., Baker, M. L. et al., Structure of double-shelled rice dwarf virus, J.Virol., 1998, 72: 8541.［4］Reinisch, K. M., Nibert, M. L., Harrison, S. C., Structure of the reovirus core at 3.6 ? resolution, Nature, 2000, 404: 960.［5］Zhang, H., Zhang, J., Yu, X. et al., Visualization of protein-RNA interactions in cytoplasmic polyhedrosis virus, J. Virol., 1999, 73: 1624.［6］Zhou, Z. H., Hardt, S., Wang, B. et al., CTF determination of images of ice-embedded single particles using a graphics inter-face, J. Struct. Biol., 1996, 116: 216.［7］Zhou, Z. H., Chiu, W., Haskell, K. et al., Refinement of herpesvirus B-capsid using parallel supercomputers, Biophys. J., 1998, 74: 576.［8］Zhou, Z. H., He, J., Jakana, J. et al., Assembly of VP26 in HSV-1 inferred from structures of wild-type and recombinant cap-sids, Nature Struct. Biol., 1995, 2: 1026.［9］Grimes, J. M., Burroughs, J. N., Patrice, G. et al., The atomic structure of the bluetongue virus core, Nature, 1998, 395: 470.［10］ Lawton, J. A., Estes, M. K., Prasad, B. V. V., Three-dimensional visualization of mRNA release from actively transcribing rotavirus particles, Nat. Struc. Bio., 1997, 4: 118.［11］ Ueda, S., Masuta, C., Uyeda, I., Hypothesis on particle structure and assembly of rice dwarf phytoreovirus: interactions among multiple structural proteins, J.Gen.Virol., 1997, 78: 3135.［12］ Kano, H., Koizumi, M., Noda, H. et al., Nucleotide sequence of rice dwarf virus(RDV) genome segment S3 coding for 114 K major core protein, Nucleic Acids Res., 1990, 18: 6700.［13］ Nakata, M., Fukunaga, K., Suzuki, N., Polypeptide components of rice dwarf virus, Ann
Andrade, Sara; Pinho, Filipa; Ribeiro, Andreia M; Carreira, Marcos; Casanueva, Felipe F; Roy, Polly; Monteiro, Mariana P
Ghrelin is a gut hormone that stimulates food intake. In physiological conditions, ghrelin plasma levels rise with fasting and decrease after meals. Obese individuals have low fasting ghrelin levels that rise after food restriction, which is pointed out as a reason for the difficulty in maintaining weight loss. Some bariatric surgery procedures prevent rise in ghrelin levels with weight loss and this has been hypothesised to contribute to the long-term success of the treatment. The main goal of this study was to develop a safe and effective anti-ghrelin vaccine for obesity, through the chemical conjugation of ghrelin with a virus like particle, namely NS1 protein tubules from the Bluetongue Virus (BTV) using a hetero-bifunctional cross linker. Male adult C57BL/6 mice, with a normal weight and with diet-induced obesity (DIO), were randomized into six weight matched groups (n=6/group) and each group of mice received three intra-peritoneal injections with two weeks intervals, containing either 75 μg of ghrelin- NS1 immunoconjugate, 75 μg of NS1 or PBS. Our data show that immunized animals present increasing titres of anti-ghrelin antibodies, while their cumulative food intake significantly decreased and energy expenditure was significantly enhanced, although there were no significative changes in body weight.Vaccinated DIO mice also displayed significant decrease of NPY gene expression in the basal hypothalamus reflecting a decrease in central orexigenic signals. This study suggests that this anti-ghrelin vaccine has a positive impact on energy homeostasis and may be an additional therapeutical tool to be used with diet and exercise for obesity treatment. PMID:23859551
Rachel E. Marschang
Full Text Available A large number of viruses have been described in many different reptiles. These viruses include arboviruses that primarily infect mammals or birds as well as viruses that are specific for reptiles. Interest in arboviruses infecting reptiles has mainly focused on the role reptiles may play in the epidemiology of these viruses, especially over winter. Interest in reptile specific viruses has concentrated on both their importance for reptile medicine as well as virus taxonomy and evolution. The impact of many viral infections on reptile health is not known. Koch’s postulates have only been fulfilled for a limited number of reptilian viruses. As diagnostic testing becomes more sensitive, multiple infections with various viruses and other infectious agents are also being detected. In most cases the interactions between these different agents are not known. This review provides an update on viruses described in reptiles, the animal species in which they have been detected, and what is known about their taxonomic positions.
... education Fact Sheet PFS005: Testing for Human Immunodeficiency Virus AUGUST 2015 • Reasons for Getting Tested • Who Should ... For More Information • Glossary Testing for Human Immunodeficiency Virus Human immunodeficiency virus (HIV) is the virus that ...
Full Text Available Security of wired and wireless networks is the most challengeable in today's computer world. The aim of this study was to give brief introduction about viruses and worms, their creators and characteristics of algorithms used by viruses. Here wired and wireless network viruses are elaborated. Also viruses are compared with human immune system. On the basis of this comparison four guidelines are given to detect viruses so that more secure systems are made. While concluding this study it is found that the security is most challengeable, thus it is required to make more secure models which automatically detect viruses and prevent the system from its affect.
Carolina Alves; Cristina Branco; Celso Cunha
The hepatitis delta virus (HDV) is distributed worldwide and related to the most severe form of viral hepatitis. HDV is a satellite RNA virus dependent on hepatitis B surface antigens to assemble its envelope and thus form new virions and propagate infection. HDV has a small 1.7 Kb genome making it the smallest known human virus. This deceivingly simple virus has unique biological features and many aspects of its life cycle remain elusive. The present review endeavors to gather the available ...
Full Text Available Of 168 patients with chronic hepatitis B virus (HBV infection-related liver disease, 20 patients who had received 100 mg of lamivudine plus 10 mg/day of adefovir dipivoxil (ADV (ADV group and 124 patients who had received 0.5 mg/day of entecavir or 100 mg/day of lamivudine (non-ADV group for >1 year were enrolled. For comparative analyses, 19 well-matched pairs were obtained from the groups by propensity scores. At the time of enrollment, serum creatinine and phosphate concentrations were similar between the ADV and non-ADV groups; however, urinary phosphate ( and serum bone-specific alkaline phosphatase (BAP ( concentrations were significantly higher in the ADV group than in the non-ADV group. Serum BAP was significantly higher at the time of enrollment than before ADV administration in the ADV group (, although there was no significant change in serum BAP concentration in the non-ADV group. There was a significant positive correlation between the period of ADV therapy and ΔBAP (, . Serum BAP concentration increased before increase in serum creatinine concentration and was useful for early detection of adverse events and for developing adequate measures for continuing ADV for chronic HBV infection-related liver disease.
The hepatitis virus panel is a series of blood tests used to detect current or past infection by hepatitis A , hepatitis ... samples for more than one kind of hepatitis virus at the same time. Antibody and antigen tests ...
The eighth volume of Advances in Viral Oncology focuses on the three major DNA virus groups with a postulated or proven tumorigenic potential: papillomaviruses, animal hepatitis viruses, and the Epstein-Bar virus. In the opening chapters, the contributors analyze the evidence that papillomaviruses and animal hepatitis viruses are involved in tumorigenesis and describe the mechanisms that trigger virus-host cell interactions. A detailed section on the Epstein-Barr virus (EBV) - comprising more than half the book - examines the transcription and mRNA processing patterns of the virus genome; the mechanisms by which EBV infects lymphoid and epithelial cells; the immunological aspects of the virus; the actions of EBV in hosts with Acquired Immune Deficiency Syndrome; and the involvement of EBV in the etiology of Burkitt's lymphoma.
Viruses are the accepted cause of many important cancers including cancers of the cervix and anogenital area, the liver, some lymphomas, head and neck cancers and indirectly human immunodeficiency virus associated cancers. For over 50 years, there have been serious attempts to identify viruses which may have a role in breast cancer. Despite these efforts, the establishment of conclusive evidence for such a role has been elusive. However, the development of extremely sophisticated new experimental techniques has allowed the recent development of evidence that human papilloma virus, Epstein-Barr virus, mouse mammary tumor virus and bovine leukemia virus may each have a role in the causation of human breast cancers. This is potentially good news as effective vaccines are already available to prevent infections from carcinogenic strains of human papilloma virus, which causes cancer of the uterine cervix
Gallo, R.C.; Haseltine, W.; Klein, G.; Zur Hausen, H.
This book contains papers on the following topics: Immunology and Epidemiology, Biology and Pathogenesis, Models of Pathogenesis and Treatment, Simian and Bovine Retroviruses, Human Papilloma Viruses, EBV and Herpesvirus, and Hepatitis B Virus.
... rashes clinical tools newsletter | contact Share | Herpes Simplex Virus (HSV) A parent's guide to condition and treatment ... skin or mouth sores with the herpes simplex virus (HSV) is called primary herpes. This may be ...
Lawson, James S., E-mail: firstname.lastname@example.org; Heng, Benjamin [School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney (Australia)
Viruses are the accepted cause of many important cancers including cancers of the cervix and anogenital area, the liver, some lymphomas, head and neck cancers and indirectly human immunodeficiency virus associated cancers. For over 50 years, there have been serious attempts to identify viruses which may have a role in breast cancer. Despite these efforts, the establishment of conclusive evidence for such a role has been elusive. However, the development of extremely sophisticated new experimental techniques has allowed the recent development of evidence that human papilloma virus, Epstein-Barr virus, mouse mammary tumor virus and bovine leukemia virus may each have a role in the causation of human breast cancers. This is potentially good news as effective vaccines are already available to prevent infections from carcinogenic strains of human papilloma virus, which causes cancer of the uterine cervix.
Ozawa, Makoto; Kawaoka, Yoshihiro
Plasmid-based reverse genetics systems allow the artificial generation of viruses with cloned cDNA-derived genomes. Since the establishment of such systems for influenza virus, numerous attempts have been made to tame this pathogenic agent. In particular, several types of viruses expressing foreign genes have been generated and used to further our knowledge of influenza virus replication and pathogenicity and to develop novel influenza vaccines. Here, we review these achievements and discuss ...
Seth Judson; Joseph Prescott; Vincent Munster
An unprecedented number of Ebola virus infections among healthcare workers and patients have raised questions about our understanding of Ebola virus transmission. Here, we explore different routes of Ebola virus transmission between people, summarizing the known epidemiological and experimental data. From this data, we expose important gaps in Ebola virus research pertinent to outbreak situations. We further propose experiments and methods of data collection that will enable scientists to fil...
Taylor, John M
This work reviews specific related aspects of hepatitis delta virus (HDV) reproduction, including virion structure, the RNA genome, the mode of genome replication, the delta antigens, and the assembly of HDV using the envelope proteins of its helper virus, hepatitis B virus (HBV). These topics are considered with perspectives ranging from a history of discovery through to still-unsolved problems. HDV evolution, virus entry, and associated pathogenic potential and treatment of infections are considered in other articles in this collection. PMID:26525452
Roossinck, Marilyn J.
The vast majority of well-characterized eukaryotic viruses are those that cause acute or chronic infections in humans and domestic plants and animals. However, asymptomatic persistent viruses have been described in animals, and are thought to be sources for emerging acute viruses. Although not previously described in these terms, there are also many viruses of plants that maintain a persistent lifestyle. They have been largely ignored because they do not generally cause disease. The persisten...
Peyrefitte, Christophe N.; Rousset, Dominique; Pastorino, Boris A.M.; Pouillot, Regis; Bessaud, Maël; Tock, Fabienne; Mansaray, Helene; Merle, Olivier L.; Pascual, Aurelie M.; Paupy, Christophe; Vessiere, Aurelia; Imbert, Patrice; Tchendjou, Patrice; Durand, Jean-Paul; Tolou, Hugues J.
We report the isolation of chikungunya virus from a patient during an outbreak of a denguelike syndrome in Cameroon in 2006. The virus was phylogenetically grouped in the Democratic Republic of the Congo cluster, indicating a continuous circulation of a genetically similar chikungunya virus population during 6 years in Central Africa.
Rajala, Judith B.
A computer virus is a program--a piece of executable code--that has the unique ability to replicate. Like biological viruses, computer viruses can spread quickly and are often difficult to eradicate. They can attach themselves to just about any type of file, and are spread by replicating and being sent from one individual to another. Simply having…
... Help White House Lunch Recipes What's West Nile Virus? KidsHealth > For Kids > What's West Nile Virus? Print A A A Text Size en español ¿Qué es el Virus del Nilo Occidental? What exactly is the West ...
... Things to Know About Zika & Pregnancy Respiratory Syncytial Virus KidsHealth > For Parents > Respiratory Syncytial Virus Print A A A Text Size What's in ... RSV When to Call the Doctor en español Virus respiratorio sincitial About RSV Respiratory syncytial (sin-SISH- ...
Bovine viral diarrhea virus (BVDV) is an umbrella term for two species of viruses, BVDV1 and BVDV2, within the Pestivirus genus of the Flavivirus family. BVDV viruses are further subclassified as cytopathic and noncytopathic based on their activity in cultured epithelial cells. Noncytopathic BVDV p...
Full Text Available An unprecedented number of Ebola virus infections among healthcare workers and patients have raised questions about our understanding of Ebola virus transmission. Here, we explore different routes of Ebola virus transmission between people, summarizing the known epidemiological and experimental data. From this data, we expose important gaps in Ebola virus research pertinent to outbreak situations. We further propose experiments and methods of data collection that will enable scientists to fill these voids in our knowledge about the transmission of Ebola virus.
Tomassoli, Laura; Tiberini, Antonio; Vetten, Heinrich-Josef
The current knowledge on viruses infecting asparagus (Asparagus officinalis) is reviewed. Over half a century, nine virus species belonging to the genera Ilarvirus, Cucumovirus, Nepovirus, Tobamovirus, Potexvirus, and Potyvirus have been found in this crop. The potyvirus Asparagus virus 1 (AV1) and the ilarvirus Asparagus virus 2 (AV2) are widespread and negatively affect the economic life of asparagus crops reducing yield and increasing the susceptibility to biotic and abiotic stress. The main properties and epidemiology of AV1 and AV2 as well as diagnostic techniques for their detection and identification are described. Minor viruses and control are briefly outlined. PMID:22682173
Kolaskar, A S; Naik, P S
A computerized animal virus information system is developed in the Sequence Retrieval System (SRS) format. This database is available on the Word Wide Web (WWW) at the site http://bioinfo.ernet.in/www/avis/avis++ +.html. The database has been used to generate large number of identification matrices for each family. The software is developed in C. Unix shell scripts and Hypertext Marked-up Language (HTML) to assign the family to an unknown virus deterministically and to identify the virus probabilistically. It has been shown that such web based virus identification approach provides results with high confidence in those cases where identification matrix uses large number of independent characters. Protein sequence data for animal viruses have been analyzed and oligopeptides specific to each virus family and also specific to each virus species are identified for several viruses. These peptides thus could be used to identify the virus and to assign the virus family with high confidence showing the usefulness of sequence data in virus identification. PMID:10917875
The use of protoplasts in the study of plant viruses has attracted considerable attention since its inception in the late 1960s. This article is an attempt to assess the current status of protoplasts (primarily) and all cell cultures (in some instances) in studies of virus infection, virus replication, cytopathology, cross-protection, virus resistance, and the use of in vitro methods and genetic engineering to recover virus-resistant plants. These areas of study proved difficult to do entirely with whole plants or plant parts. However, because protoplasts could be synchronously infected with virus, they provided a valuable alternative means of following biochemical and cytological events in relation to the virus growth cycle in a more precise manner than previously possible
RNA viruses are viruses whose genetic material is ribonucleic acid (RNA). RNA viruses may be double or single-stranded based on the type of RNA they contain. Single-stranded RNA viruses can be further grouped into negative sense or positive-sense viruses according to the polarity of their RNA. Fur...
Goldberg, L.A. [Warwick Univ., Coventry (United Kingdom) Dept. of Computer Science; Goldberg, P.W. [Aston Univ., Birmingham (United Kingdom) Dept. of Applied Mathematics; Phillips, C.A. [Sandia National Labs., Albuquerque, NM (United States); Sorkin, G.B. [International Business Machines Corp., Yorktown Heights, NY (United States). Thomas J. Watson Research Center
There has been much recent algorithmic work on the problem of reconstructing the evolutionary history of biological species. Computer virus specialists are interested in finding the evolutionary history of computer viruses--a virus is often written using code fragments from one or more other viruses, which are its immediate ancestors. A phylogeny for a collection of computer viruses is a directed acyclic graph whose nodes are the viruses and whose edges map ancestors to descendants and satisfy the property that each code fragment is ``invented`` only once. To provide a simple explanation for the data, we consider the problem of constructing such a phylogeny with a minimal number of edges. In general, this optimization problem cannot be solved in quasi-polynomial time unless NQP=QP; we present positive and negative results for associated approximated problems. When tree solutions exist, they can be constructed and randomly sampled in polynomial time.
Sulfated polysaccharides are potent and selective inhibitors of various enveloped viruses, including herpes simplex virus, cytomegalovirus, vesicular stomatitis virus, and human immunodeficiency virus.
Baba, M.; Snoeck, R; Pauwels, R; De Clercq, E
Several sulfated polysaccharides (dextran sulfate, pentosan polysulfate, fucoidan, and carrageenans) proved to be potent inhibitors for herpes simplex virus, human cytomegalovirus, vesicular stomatitis virus, Sindbis virus, and human immunodeficiency virus. They were moderately inhibitory to vaccinia virus but not inhibitory to adenovirus, coxsackievirus, poliovirus, parainfluenza virus, and reovirus. These results indicate that, with the exception of parainfluenza virus, enveloped viruses ar...
Zanluca, Camila; Dos Santos, Claudia Nunes Duarte
Zika virus (ZIKV) is currently one of the most important emerging viruses in the world. Recently, it has caused outbreaks and epidemics, and has been associated with severe clinical manifestations and congenital malformations. However to date, little is known about the pathogenicity of the virus and the consequences of ZIKV infection. In this paper, we provide an overview of the current knowledge on ZIKV. PMID:26993028
Salomon, Rachelle; Webster, Robert G.
Both seasonal and pandemic influenza continue to challenge both scientists and clinicians. Drug-resistant H1N1 influenza viruses have dominated the 2009 flu season, and the H5N1 avian influenza virus continues to kill both people and poultry in Eurasia. Here, we discuss the pathogenesis and transmissibility of influenza viruses and we emphasize the need to find better predictors of both seasonal and potentially pandemic influenza.
Lakadamyali, Melike; Rust, Michael J.; Zhuang, Xiaowei
Receptor-mediated endocytosis is known to play an important role in the entry of many viruses into host cells. However, the exact internalization mechanism has, until recently, remained poorly understood for many medically important viruses, including influenza. Developments in real-time imaging of single viruses as well as the use of dominant negative mutants to selectively block specific endocytic pathways, have improved our understanding of the influenza infection process.
Dadonaite, Bernadeta; Vijyakrishnan, Swetha; Fodor, Ervin; Bhella, David; Hutchinson, Edward C.
Clinical isolates of influenza virus produce pleomorphic virus particles, including extremely long filamentous virions. In contrast, strains of influenza that have adapted to laboratory growth typically produce only spherical virions. As a result, the filamentous phenotype has been overlooked in most influenza virus research. Recent advances in imaging and improved animal models have highlighted the distinct structure and functional relevance of filamentous virions. In this review we summaris...
Kjær, Peter; Frankel, Christian
The virus metaphor may be used in studies of management knowledge not only as a way of describing diffusion processes but also as a way of thinking about viral elements of knowledge production. In the present article, organizational viruses are viewed as ensembles of basic distinctions that are constitutive of concrete bodies of knowledge and which form mutable engines of organizational self-descriptions. Organizational viruses, we contend, are both characterized by stability i...
Cohen and his supervisor Adleman defined a virus as follows: "A virus is a program that is able to infect other programs by modifying them to include a possibly evolved copy to itself". This definition seems to be well accepted by the computer security community as a foundational definition. Thus, a virus is a self-replicating program, whose offspring may be a mutation of the original program. Viruses thrive in our computers, which are based on Turing's model of computation. We discuss the fu...
McKercher, P D; Hess, W R; Hamdy, F
Partly cooked canned hams and dried pepperoni and salami sausages were prepared from the carcasses of pigs infected with African swine fever virus and pigs infected with hog cholera virus. Virus was not recovered from the partly cooked canned hams; however, virus was recovered in the hams before heating in both instances. Both African swine fever virus and hog cholera virus were recovered from the dried salami and pepperoni sausages, but not after the required curing period. PMID:564162
... Public Service Videos General Questions About West Nile Virus Recommend on Facebook Tweet Share Compartir On this ... West Nile virus cases? What is West Nile virus? West Nile virus is an arthropod-borne virus ( ...
Olesen, Niels Jørgen; Skall, Helle Frank
This chapter covers the genetics (genotypes and serotypes), clinical signs, host species, transmission, prevalence, diagnosis, control and prevention of viral haemorrhagic septicaemia virus.......This chapter covers the genetics (genotypes and serotypes), clinical signs, host species, transmission, prevalence, diagnosis, control and prevention of viral haemorrhagic septicaemia virus....
Avian influenza virus (AIV) is normally found in wild birds, particularly in ducks and shorebirds, where it does not cause any perceptible clinical disease. However, poultry, including chickens and turkeys, are not normal hosts for avian influenza, but if the virus is introduced it can result in mi...
Stagg, Denise; Hurst, Helen M
Recent outbreaks of Zika virus and reports linking infection in pregnant women with microcephaly in newborns have caused concern worldwide. Information has been evolving rapidly. Nurses and other clinicians, especially those who work with women of childbearing age, play a pivotal role in disseminating accurate information and identifying potential cases of Zika virus infection. PMID:27287356
Papaya ringspot virus, a member of the family Potyviridae, is single stranded RNA plant virus with a monocistronic genome of about 10,326 nucleotides that is expressed via a large polyprotein subsequently cleaved into functional proteins. It causes severe damage on cucurbit crops such as squash and...
Olesen, Niels Jørgen; Skall, Helle Frank
This chapter covers the genetics (genotypes and serotypes), clinical signs, host species, transmission, prevalence, diagnosis, control and prevention of viral haemorrhagic septicaemia virus.......This chapter covers the genetics (genotypes and serotypes), clinical signs, host species, transmission, prevalence, diagnosis, control and prevention of viral haemorrhagic septicaemia virus....
Rift Valley fever virus (RVFV) is a mosquito-transmitted virus or arbovirus that is endemic in sub-Saharan Africa. In the last decade, Rift Valley fever (RVF) outbreaks have resulted in loss of human and animal life, as well as had significant economic impact. The disease in livestock is primarily a...
Maxwell, John R.; Lamon, William E.
Explains how computer viruses were originally created, how a computer can become infected by a virus, how viruses operate, symptoms that indicate a computer is infected, how to detect and remove viruses, and how to prevent a reinfection. A sidebar lists eight antivirus resources. (four references) (LRW)
Prescott, Joseph; Bushmaker, Trenton; Fischer, Robert; Miazgowicz, Kerri; Judson, Seth; Vincent J. Munster
The ongoing Ebola virus outbreak in West Africa has highlighted questions regarding stability of the virus and detection of RNA from corpses. We used Ebola virus–infected macaques to model humans who died of Ebola virus disease. Viable virus was isolated
A description is presented of a radioimmunoassay designed to prove the presence of the antibody against the hepatitis A virus (HA Ab, anti-Ha) using an Abbott HAVAB set. This proof as well as the proof of the antibody against the nucleus of the hepatitis B virus is based on competition between a normal antibody against hepatitis A virus and a 125I-labelled antibody for the binding sites of a specific antigen spread all over the surface of a tiny ball; this is then indirect proof of the antibody under investigation. The method is described of reading the results from the number of impulses per 60 seconds: the higher the titre of the antibody against the hepatitis A virus in the serum examined, the lower the activity of the specimen concerned. The rate is reported of incidence of the antibody against the hepatitis A virus in a total of 68 convalescents after hepatitis A; the antibody was found in 94.1%. The immunoglobulin made from the convalescents' plasma showed the presence of antibodies in dilutions as high as 1:250 000 while the comparable ratio for normal immunoglobulin Norga was only 1:2500. Differences are discussed in the time incidence of the antibodies against the hepatitis A virus, the antibodies against the surface antigen of hepatitis B, and the antibody against the nucleus of the hepatitis V virus. (author)
Smith, S M; Danganan, L; Tammero, L; Vitalis, B; Lenhoff, R; Naraghi-arani, P; Hindson, B
Lawrence Livermore National Laboratory (LLNL), in collaboration with the Department of Homeland Security (DHS) and the United States Department of Agriculture (USDA), Animal and Plant Health Inspection Services (APHIS) has developed candidate multiplexed assays that may potentially be used within the National Animal Health Laboratory Network (NAHLN), the National Veterinary Services Laboratory (Ames, Iowa) and the Plum Island Animal Disease Center (PIADC). This effort has the ability to improve our nation's capability to discriminate between foreign animal diseases and those that are endemic using a single assay, thereby increasing our ability to protect food and agricultural resources with a diagnostic test which could enhance the nation's capabilities for early detection of a foreign animal disease. In FY2005 with funding from the DHS, LLNL developed the first version (Version 1.0) of a multiplexed (MUX) nucleic-acid-based RT-PCR assay that included signatures for foot-and-mouth disease virus (FMDV) detection with rule-out tests for two other foreign animal diseases (FADs) of swine, Vesicular Exanthema of Swine (VESV) and Swine Vesicular Disease Virus (SVDV), and four other domestic viral diseases Bovine Viral Diarrhea Virus (BVDV), Bovine Herpes Virus 1 (BHV-1), Bluetongue virus (BTV) and Parapox virus complex (which includes Bovine Papular Stomatitis Virus [BPSV], Orf of sheep, and Pseudocowpox). In FY06, LLNL has developed Bovine and Porcine species-specific panel which included existing signatures from Version 1.0 panel as well as new signatures. The MUX RT-PCR porcine assay for detection of FMDV includes the FADs, VESV and SVD in addition to vesicular stomatitis virus (VSV) and porcine reproductive and respiratory syndrome (PRRS). LLNL has also developed a MUX RT-PCR bovine assay for detection of FMDV with rule out tests for the two bovine FADs malignant catarrhal fever (MCF), rinderpest virus (RPV) and the domestic diseases vesicular stomatitis
The work presented in this thesis provides novel insights in several aspects of the molecular biology of archaea, bacteria and their viruses. Three fundamentally different groups of viruses are associated with the three domains of life. Archaeal viruses are characterized by a particularly high morphological and genetic diversity. Some archaeal viruses, such as Sulfolobus islandicus rod-shaped virus 2 (SIRV2), have quite remarkable infection cycles. As described in Chapter 1, infection ...
Full Text Available Abstract The etiology of reptilian viral diseases can be attributed to a wide range of viruses occurring across different genera and families. Thirty to forty years ago, studies of viruses in reptiles focused mainly on the zoonotic potential of arboviruses in reptiles and much effort went into surveys and challenge trials of a range of reptiles with eastern and western equine encephalitis as well as Japanese encephalitis viruses. In the past decade, outbreaks of infection with West Nile virus in human populations and in farmed alligators in the USA has seen the research emphasis placed on the issue of reptiles, particularly crocodiles and alligators, being susceptible to, and reservoirs for, this serious zoonotic disease. Although there are many recognised reptilian viruses, the evidence for those being primary pathogens is relatively limited. Transmission studies establishing pathogenicity and cofactors are likewise scarce, possibly due to the relatively low commercial importance of reptiles, difficulties with the availability of animals and permits for statistically sound experiments, difficulties with housing of reptiles in an experimental setting or the inability to propagate some viruses in cell culture to sufficient titres for transmission studies. Viruses as causes of direct loss of threatened species, such as the chelonid fibropapilloma associated herpesvirus and ranaviruses in farmed and wild tortoises and turtles, have re-focused attention back to the characterisation of the viruses as well as diagnosis and pathogenesis in the host itself. 1. Introduction 2. Methods for working with reptilian viruses 3. Reptilian viruses described by virus families 3.1. Herpesviridae 3.2. Iridoviridae 3.2.1 Ranavirus 3.2.2 Erythrocytic virus 3.2.3 Iridovirus 3.3. Poxviridae 3.4. Adenoviridae 3.5. Papillomaviridae 3.6. Parvoviridae 3.7. Reoviridae 3.8. Retroviridae and inclusion body disease of Boid snakes 3.9. Arboviruses 3.9.1. Flaviviridae 3
Olesen, Niels Jørgen; Skall, Helle Frank
worldwide distribution of the disease will be given. Virus evolution: Recent studies indicate that only a few amino acid changes in the structural proteins of VHSV can change the virulence patterns significantly, thereby coming closer to assessing the risk of none to low virulent viruses becoming high...... virulent. Virulence factors both depend on the ability of VHSV to enter a cell and on the speed and efficiency of virus replication in the cells. Apparently the viral nucleocapsid protein plays a very important role for the later and seems to be the target for determination of a virulence marker....
Skall, Helle Frank; Olesen, Niels Jørgen
worldwide distribution of the disease will be given. Virus evolution: Recent studies indicate that only a few amino acid changes in the structural proteins of VHSV can change the virulence patterns significantly, thereby coming closer to assessing the risk of none to low virulent viruses becoming high...... virulent. Virulence factors both depend on the ability of VHSV to enter a cell and on the speed and efficiencyof virus replication in the cells. Apparently the viral nucleocapsid protein plays a very important role for the later and seems to be the target for determination of a virulence marker....
... medical care and advice. There is currently no vaccine available. Prevention Mosquito bites Protection against mosquito bites is a key measure to prevent Zika virus infection. This can be done by wearing ...
Vasiliy Ivanovich Reshetnyak; Tatiana Igorevna Karlovich; Ljudmila Urievna Ilchenko
A number of new hepatitis viruses (G,TT,SEN) were discovered late in the past century.We review the data available in the literature and our own findings suggesting that the new hepatitis G virus (HGV),disclosed in the late 1990s,has been rather well studied.Analysis of many studies dealing with HGV mainly suggests the lymphotropicity of this virus.HGV or GBV-C has been ascertained to influence course and prognosis in the HIV-infected patient.Until now,the frequent presence of GBV-C in coinfections,hematological diseases,and biliary pathology gives no grounds to determine it as an "accidental tourist" that is of no significance.The similarity in properties of GBV-C and hepatitis C virus (HCV) offers the possibility of using HGV,and its induced experimental infection,as a model to study hepatitis C and to develop a hepatitis C vaccine.
Del Carpio-Orantes, Luis
In this paper, the neurotropism potential Zika virus is discussed, by comparison with viruses both RNA and DNA are neurotropic known, also it is said that compared with the new viruses that have affected the Americas, as the chikungunya, Zika has shown great affinity by brain tissue, manifested by a high incidence of acute neurological conditions, such as Guillain-Barré syndrome, among others, as well as the reported incidence of microcephaly that is abnormally high compared with the previous incidence, which, in a stillborn subject necropsied significant alterations demonstrated in brain tissue, identifying viral material and live virus in the fetoplacental complex, and demonstrating the impact both white matter and gray matter as well as basal ganglia, corpus callosum, ventricles and spinal cord, which could explain the microcephaly that concerns him. Although not a direct cause-effect relationship is demonstrated, however current evidence supports that relationship, hoping to be supported scientifically. PMID:27197113
Konvalinka, Jan; Kräusslich, H. G.
Amsterdam: Academic Press, 2013 - (Salvesen, G.), s. 204-207 ISBN 978-0-12-382219-2 Institutional support: RVO:61388963 Keywords : simian immunodeficiency virus * retropepsin * protease Subject RIV: CE - Biochemistry
... long as their blood contains the virus. Sexual transmission More surveillance data and research are needed on the risks of sexual transmission, and particularly on the prevalence of viable and ...
Hayes, Edward B
Zika virus (ZIKV) is a flavivirus related to yellow fever, dengue, West Nile, and Japanese encephalitis viruses. In 2007 ZIKV caused an outbreak of relatively mild disease characterized by rash, arthralgia, and conjunctivitis on Yap Island in the southwestern Pacific Ocean. This was the first time that ZIKV was detected outside of Africa and Asia. The history, transmission dynamics, virology, and clinical manifestations of ZIKV disease are discussed, along with the possibility for diagnostic ...
Mahalingam, Ravi; Messaoudi, Ilhem; Gilden, Don
Because varicella zoster virus (VZV) is an exclusively human pathogen, the development of an animal model is necessary to study pathogenesis, latency, and reactivation. The pathological, virological, and immunological features of simian varicella virus (SVV) infection in nonhuman primates are similar to those of VZV infection in humans. Both natural infection of cynomolgus and African green monkeys as well as intrabronchial inoculation of rhesus macaques with SVV provide the most useful model...
Respiratory Syncytial Virus, or RSV, causes cold-like symptoms but can be serious for infants and older adults. In this podcast, CDCâs Dr. Eileen Schneider discusses this common virus and offers tips to prevent its spread. Created: 2/4/2013 by National Center for Immunization and Respiratory Diseases (NCIRD), Division of Viral Diseases (DVD). Date Released: 2/13/2013.
As the anti-viruses run in a trusted kernel level any loophole in the anti-virus program can enable attackers to take full control over the computer system and steal data or do serious damages. Hence the anti-virus engines must be developed with proper security in mind. The ant-virus should be able to any type of specially created executable files, compression packages or documents that are intentionally created to exploit the anti-virus weakness. Viruses are present in almost every system ev...
Aljabali, Alaa A. A.; Barclay, J. Elaine; Lomonossoff, George P.; Evans, David J.
Plant viruses are considered as nanobuilding blocks that can be used as synthons or templates for novel materials. Cowpea mosaic virus (CPMV) particles have been shown to template the fabrication of metallic nanoparticles by an electroless deposition metallization process. Palladium ions were electrostatically bound to the virus capsid and, when reduced, acted as nucleation sites for the subsequent metal deposition from solution. The method, although simple, produced highly monodisperse metallic nanoparticles with a diameter of ca. templated particles were prepared with cobalt, nickel, iron, platinum, cobalt-platinum and nickel-iron.Plant viruses are considered as nanobuilding blocks that can be used as synthons or templates for novel materials. Cowpea mosaic virus (CPMV) particles have been shown to template the fabrication of metallic nanoparticles by an electroless deposition metallization process. Palladium ions were electrostatically bound to the virus capsid and, when reduced, acted as nucleation sites for the subsequent metal deposition from solution. The method, although simple, produced highly monodisperse metallic nanoparticles with a diameter of ca. templated particles were prepared with cobalt, nickel, iron, platinum, cobalt-platinum and nickel-iron. Electronic supplementary information (ESI) available: Additional experimental detail, agarose gel electrophoresis results, energy dispersive X-ray spectra, ζ-potential measurements, dynamic light scattering data, nanoparticle tracking analysis and an atomic force microscopy image of Ni-CPMV. See DOI: 10.1039/c0nr00525h
... Past Newsletters Avian Influenza A Virus Infections in Humans Language: English EspaÃ±ol Recommend on Facebook Tweet ... A Viruses Avian Influenza A Virus Infections in Humans Although avian influenza A viruses usually do not ...
HE Hongjun; CAO Sihua; LUO Li; FENG Tao; PAN Li; ZOU Zhiji
Security experts have not formally defined the distinction between viruses and normal programs. The paper takes user's intension as the criteria for malice, gives a formal definition of viruses that aim at stealing or destroying files, and proposes an algorithm to detect virus correctly. Compared with traditional definitions, this new definition is easy to understand, covers more malwares, adapts development of virus technology, and defines virus on the spot. The paper has also analyzed more than 250 real viruses and finds that they are all in the domain of the new definition, this implies that the new definition has great practical significance.
Picone, O; Vauloup-Fellous, C; D'Ortenzio, E; Huissoud, C; Carles, G; Benachi, A; Faye, A; Luton, D; Paty, M-C; Ayoubi, J-M; Yazdanpanah, Y; Mandelbrot, L; Matheron, S
A Zika virus epidemic is currently ongoing in the Americas. This virus is linked to congenital infections with potential severe neurodevelopmental dysfunction. However, incidence of fetal infection and whether this virus is responsible of other fetal complications are still unknown. National and international public health authorities recommend caution and several prevention measures. Declaration of Zika virus infection is now mandatory in France. Given the available knowledge on Zika virus, we suggest here a review of the current recommendations for management of pregnancy in case of suspicious or infection by Zika virus in a pregnant woman. PMID:27079865
Purcell, R H
Viral hepatitis is a disease of antiquity, but evidence for more than one etiologic agent has been recognized only since the 1940s, when two viruses (hepatitis A virus and hepatitis B virus) were thought to account for all disease. In the past 20 years, three additional hepatitis agents (hepatitis C virus, hepatitis D virus, and hepatitis E virus) have been discovered, and there is evidence for at least one additional virus. Each of the five recognized hepatitis viruses belongs to a different...
Acute respiratory illness (ARI) due to various viruses is not only the most common cause of upper respiratory infection in humans but is also a major cause of morbidity and mortality, leading to diseases such as bronchiolitis and pneumonia. Previous studies have shown that respiratory syncytial virus (RSV), human rhinovirus (HRV), human metapneumovirus (HMPV), human parainfluenza virus (HPIV), and human enterovirus (HEV) infections may be associated with virus-induced asthma. For example, it ...
Perkus, Marion E.; Piccini, Antonia; Lipinskas, Bernard R.; Paoletti, Enzo
The coding sequences for the hepatitis B virus surface antigen, the herpes simplex virus glycoprotein D, and the influenza virus hemagglutinin were inserted into a single vaccinia virus genome. Rabbits inoculated intravenously or intradermally with this polyvalent vaccinia virus recombinant produced antibodies reactive to all three authentic foreign antigens. In addition, the feasibility of multiple rounds of vaccination with recombinant vaccinia virus was demonstrated.
Full Text Available Viruses are known to be abundant, ubiquitous, and to play a very important role in the health and evolution of life organisms. However, most biologists have considered them as entities separate from the realm of life and acting merely as mechanical artifacts that can exchange genes between different organisms. This article reviews some definitions of life organisms to determine if viruses adjust to them, and additionally, considers new discoveries to challenge the present definition of viruses. Definitions of life organisms have been revised in order to validate how viruses fit into them. Viral factories are discussed since these mini-organelles are a good example of the complexity of viral infection, not as a mechanical usurpation of cell structures, but as a driving force leading to the reorganization and modification of cell structures by viral and cell enzymes. New discoveries such as the Mimivirus, its virophage and viruses that produce filamentous tails when outside of their host cell, have stimulated the scientific community to analyze the current definition of viruses. One way to be free for innovation is to learn from life, without rigid mental structures or tied to the past, in order to understand in an integrated view the new discoveries that will be unfolded in future research. Life processes must be looked from the complexity and trans-disciplinarity perspective that includes and accepts the temporality of the active processes of life organisms, their interdependency and interrelation among them and their environment. New insights must be found to redefine life organisms, especially viruses, which still are defined using the same concepts and knowledge of the fifties. Rev. Biol. Trop. 59 (3: 993-998. Epub 2011 September 01.Los virus son abundantes, ubicuos, y juegan un papel muy importante en la salud y en la evolución de los organismos vivos. Sin embargo, la mayoría de los biólogos los siguen considerado como entidades separadas
Full Text Available Pollination of flowering plants is an important ecosystem service provided by wild insect pollinators and managed honey bees. Hence, losses and declines of pollinating insect species threaten human food security and are of major concern not only for apiculture or agriculture but for human society in general. Honey bee colony losses and bumblebee declines have attracted intensive research interest over the last decade and although the problem is far from being solved we now know that viruses are among the key players of many of these bee losses and bumblebee declines. With this special issue on bee viruses we, therefore, aimed to collect high quality original papers reflecting the current state of bee virus research. To this end, we focused on newly discovered viruses (Lake Sinai viruses, bee macula-like virus, or a so far neglected virus species (Apis mellifera filamentous virus, and cutting edge technologies (mass spectrometry, RNAi approach applied in the field.
J Gordon Millichap
A Task Force established by the Brazil Ministry of Health investigated the possible association of microcephaly with Zika virus infection during pregnancy and a registry for microcephaly cases among women suspected to have had Zika virus infection during pregnancy.
Malik Peiris, J S
Past pandemics arose from low pathogenic avian influenza (LPAI) viruses. In more recent times, highly pathogenic avian influenza (HPAI) H5N1, LPAI H9N2 and both HPAI and LPAI H7 viruses have repeatedly caused zoonotic disease in humans. Such infections did not lead to sustained human-to-human transmission. Experimental infection of human volunteers and seroepidemiological studies suggest that avian influenza viruses of other subtypes may also infect humans. Viruses of the H7 subtype appear to...
Arding, Petter; Hedelin, Hugo
Computer viruses uses a few different techniques, with various intentions, toinfect files. However, what most of them have in common is that they wantto avoid detection by anti-malware software. To not get detected and stay unnoticed,virus creators have developed several methods for this. Anti-malwaresoftware is constantly trying to counter these methods of virus infections withtheir own detection-techniques. In this paper we have analyzed the differenttypes of viruses and their infection tec...
Wiktor, TJ; Koprowski, H
Antigenic variants of CVS-11 strain of rabies virus were selected after treatment of virus populations with monoclonal antibodies directed against the glycoprotein antigen of the virus. These variants resisted neutralization by the hybridoma antibody used for their selection. Two independently mutating antigenic sites could be distinguished when five variants were tested with nine hybridoma antibodies. The frequency of single epitope variants in a cloned rabies virus seed was approximately 1:...
Full Text Available Influenza virus is the most frequently reported viral cause of rhabdomyolysis. A 7-year-old child is presented with rhabdomyolysis associated with parainfluenza type 2 virus. Nine cases of rhabdomyolysis associated with parainfluenza virus have been reported. Complications may include electrolyte disturbances, acute renal failure, and compartment syndrome.
The work presented in this thesis provides novel insights in several aspects of the molecular biology of archaea, bacteria and their viruses. Three fundamentally different groups of viruses are associated with the three domains of life. Archaeal viruses are characterized by a particularly
Descy, Don E.
A computer virus is defined as a software program capable of reproducing itself and usually capable of causing great harm to files or other programs on the same computer. The existence of computer viruses--or the necessity of avoiding viruses--is part of using a computer. With the advent of the Internet, the door was opened wide for these…
Ipomoviruses including Squash vein yellowing virus, Cucumber vein yellowing virus and Cassava brown streak virus are currently causing significant economic impact on crop production in several regions of the world. Only recently have results of detailed characterization of their whitefly transmissi...
Bouvier, Nicole M.; Palese, Peter
The influenza viruses are characterized by segmented, negative-strand RNA genomes requiring an RNA-dependent RNA polymerase of viral origin for replication. The particular structure of the influenza virus genome and function of its viral proteins enable antigenic drift and antigenic shift. These processes result in viruses able to evade the long-term adaptive immune responses in many hosts.
The efficient extraction and purification of viral RNA is critical for down-stream molecular applications whether it is the sensitive and specific detection of virus in clinical samples, virus gene cloning and expression, or quantification of avian influenza (AI) virus by molecular methods from expe...
Schupp, Dorothee Carolin
Viruses are known to cause many diseases, from the common cold and cold sores to more serious diseases such as the Ebola virus disease and AIDS. Viruses have evolved different strategies to enter and infect cells. In order to infect a cell, viruses have to overcome the cell membrane barrier to deliver their genome to the site of replication. Enveloped viruses can either fuse directly at the plasma membrane or with an endosomal membrane after endocytic uptake. In this work, I studied the early...
Hunter, B G; Smith, J; Fattouh, F; Jackson, A O
Barley stripe mosaic virus (BSMV), poa semilatent virus (PSLV), and lychnis ringspot virus (LRSV) have previously been assigned to the hordeivirus group because of similarities in their particle morphology, physicochemical properties and serological analyses. However, the serological relationships of the three viruses have not been determined by direct comparison. The present study evaluated the relatedness of these viruses by Western and dot immunoblotting and by nucleic acid hybridizations. Serological analyses of the coat proteins separated by gel electrophoresis and of intact virus particles bound to nitrocellulose membranes revealed that BSMV and PSLV are distantly related, but that they are more closely related to each other than to LRSV. The genomic RNAs of the viruses failed to cross-hybridize in northern hybridization tests conducted at different temperatures. These comparisons showed that BSMV, PSLV and LRSV are distinct viruses with little nucleotide sequence relatedness. Thus our data provide additional support for their inclusion as separate members of the hordeivirus group. PMID:2722469
The growing proliferation of computer viruses becomes the lethal threat and research focus of the security of network information. While new virus is emerging, the number of viruses is growing, virus classification increasing complex. Virus naming because of agencies' capture time differences can not be unified. Although each agency has its own virus database, the communication between each other lacks, or virus information is incomplete, or a small number of sample information. This paper introduces the current construction status of the virus database at home and abroad, analyzes how to standardize and complete description of virus characteristics, and then gives the information integrity, storage security and manageable computer virus database design scheme.
Hernández Vigueras, Scarlette; Salazar Navarrete, Luis; Pérez Tomás, Ricardo E.; Segura Egea, Juan José; Viñas, Miquel; López López, José
La infección endodóntica es la infección que afecta al sistema de conductos radiculares y, sin duda, es el principal agente etiológico de las periodontitis apicales. Además, de las bacterias patógenas endodónticas, se ha buscado en los últimos años asociar la presencia de virus en distintos tipos de patología endodóntica. Los virus que más se han buscado y asociado son los pertenecientes a la familia herpesvirus, los cuales se han encontrado presentes en patologías periapicales principalmente...
Mourya, Devendra T.; Shil, Pratip; Sapkal, Gajanan N.; Yadav, Pragya D.
The emergence of Zika virus (ZiV), a mosquito borne Flavivirus like dengue (DEN) and chikungunya (CHIK), in Brazil in 2014 and its spread to various countries have led to a global health emergency. Aedes aegypti is the major vector for ZiV. Fast dissemination of this virus in different geographical areas posses a major threat especially to regions where the population lacks herd immunity against the ZiV and there is abundance of Aedes mosquitoes. In this review, we focus on current global scenario, epidemiology, biology, diagnostic challenges and remedial measures for ZiVconsidering the Indian perspective. PMID:27487998
This review summarizes the knowledge of the scientific community for Zika-virus infection. It became popular because of severe congenital damage causes of CNS in newborns whose mothers are infected during pregnancy, as well as the risk of pandemic distribution. Discusses the peculiarities of the biology and ecology of vectors--blood-sucking mosquitoes Aedes; stages in the spread of infection and practical problems which caused during pregnancy. Attention is paid to the recommendations that allow leading national and international medical organizations to deal with the threat Zika-virus infection. PMID:27509655
Mourya, Devendra T; Shil, Pratip; Sapkal, Gajanan N; Yadav, Pragya D
The emergence of Zika virus (ZiV), a mosquito borne Flavivirus like dengue (DEN) and chikungunya (CHIK), in Brazil in 2014 and its spread to various countries have led to a global health emergency. Aedes aegypti is the major vector for ZiV. Fast dissemination of this virus in different geographical areas posses a major threat especially to regions where the population lacks herd immunity against the ZiV and there is abundance of Aedes mosquitoes. In this review, we focus on current global scenario, epidemiology, biology, diagnostic challenges and remedial measures for ZiVconsidering the Indian perspective. PMID:27487998
Jensen, Søren; Thomsen, Allan Randrup
Our knowledge regarding the contribution of the innate immune system in recognizing and subsequently initiating a host response to an invasion of RNA virus has been rapidly growing over the last decade. Descriptions of the receptors involved and the molecular mechanisms they employ to sense viral...... pathogen-associated molecular patterns have emerged in great detail. This review presents an overview of our current knowledge regarding the receptors used to detect RNA virus invasion, the molecular structures these receptors sense, and the involved downstream signaling pathways....
Full Text Available Se presenta a la consulta un hombre proveniente de la República Dominicana con una tenosinovitis del extensor del dedo medio derecho; en la convalecencia inmediata, segunda curva febril luego de 48 horas de permanecer asintomático de una enfermedad febril aguda, y marcada astenia, exantema pruriginoso, poliartralgias con impotencia funcional y rigidez articular generalizada. Los exámenes bioquímicos no aportaron datos de interés para el diagnóstico. La serología para virus dengue fue negativa. La detección de IgM y de anticuerpos neutralizantes para virus Chikungunya (CHIKV fueron positivos.
Devendra T Mourya
Full Text Available The emergence of Zika virus (ZiV, a mosquito borne Flavivirus like dengue (DEN and chikungunya (CHIK, in Brazil in 2014 and its spread to various countries have led to a global health emergency. Aedes aegypti is the major vector for ZiV. Fast dissemination of this virus in different geographical areas posses a major threat especially to regions where the population lacks herd immunity against the ZiV and there is abundance of Aedes mosquitoes. In this review, we focus on current global scenario, epidemiology, biology, diagnostic challenges and remedial measures for ZiVconsidering the Indian perspective.
Hoar, Bruce R.
Bovine virus diarrhea (BVD) is a complicated disease to discuss as it can result in a wide variety of disease problems from very mild to very severe. BVD can be one of the most devastating diseases cattle encounter and one of the hardest to get rid of when it attacks a herd. The viruses that cause BVD have been grouped into two genotypes, Type I and Type II. The disease syndrome caused by the two genotypes is basically the same, however disease caused by Type II infection is often more severe...
Culicoides sonorensis is the primary vector of bluetongue and epizootic hemorrhagic disease viruses in North America. Bluetongue disease is considered one of the most economically important arthropod-borne diseases of sheep in North America because it causes significant morbidity and mortality and ...
Huang, Ying; Chen, Zhenhai; Huang, Junhua; Fu, Zhenfang; He, Biao
Rabies remains a major public health threat around the world. Once symptoms appear, there is no effective treatment to prevent death. In this work, we tested a recombinant parainfluenza virus 5 (PIV5) strain expressing the glycoprotein (G) of rabies (PIV5-G) as a therapy for rabies virus infection: we have found that PIV5-G protected mice as late as 6 days after rabies virus infection. PIV5-G is a promising vaccine for prevention and treatment of rabies virus infection.
Francis, Roy Mathew; Kryger, Per
A new RT-PCR primer pair designed to identify Acute Bee Paralysis Virus (ABPV), Kashmir Bee Virus (KBV) or Israeli Acute Bee Paralysis Virus (IAPV) of honey bees (Apis mellifera L.) in a single assay is described. These primers are used to screen samples for ABPV, KBV, or IAPV in a single RT...
van Rijn, Patrick; Schirhagl, Romana
Nanobiomaterials such as virus particles and artificial virus particles offer tremendous opportunities to develop new biomedical applications such as drug- or gene-delivery, imaging and sensing but also improve understanding of biological mechanisms. Recent advances within the field of virus-based s
O'Shea, Thomas; Cryan, Paul M.; Cunningham, Andrew A.; Fooks, Anthony R.; Hayman, David T.S.; Luis, Angela D.; Peel, Alison J.; Plowright, Raina K.; Wood, James L.N.
Bats are sources of high viral diversity and high-profile zoonotic viruses worldwide. Although apparently not pathogenic in their reservoir hosts, some viruses from bats severely affect other mammals, including humans. Examples include severe acute respiratory syndrome coronaviruses, Ebola and Marburg viruses, and Nipah and Hendra viruses. Factors underlying high viral diversity in bats are the subject of speculation. We hypothesize that flight, a factor common to all bats but to no other mammals, provides an intensive selective force for coexistence with viral parasites through a daily cycle that elevates metabolism and body temperature analogous to the febrile response in other mammals. On an evolutionary scale, this host–virus interaction might have resulted in the large diversity of zoonotic viruses in bats, possibly through bat viruses adapting to be more tolerant of the fever response and less virulent to their natural hosts.
Discussion of human performance technology (HPT) interventions focuses on requests for solutions to problems that involve conflict between the FEFM ("Fix 'em for me") Virus and the WIIFM ("What's in it for me?") Requirement. Building a relationship of mutual trust and confidence with the client and demonstrating responsiveness are advocated. (LRW)
The Panda, a computer infection that wreaked havoc on computers across China, brought attention to the country’s underground computer virus business, but it was just the tip of a growing iceberg The cute and cuddly panda, a nation- al treasure of China
Alison W. S. Luk
Full Text Available In hypersaline environments, haloarchaea (halophilic members of the Archaea are the dominant organisms, and the viruses that infect them, haloarchaeoviruses are at least ten times more abundant. Since their discovery in 1974, described haloarchaeoviruses include head-tailed, pleomorphic, spherical and spindle-shaped morphologies, representing Myoviridae, Siphoviridae, Podoviridae, Pleolipoviridae, Sphaerolipoviridae and Fuselloviridae families. This review overviews current knowledge of haloarchaeoviruses, providing information about classification, morphotypes, macromolecules, life cycles, genetic manipulation and gene regulation, and host-virus responses. In so doing, the review incorporates knowledge from laboratory studies of isolated viruses, field-based studies of environmental samples, and both genomic and metagenomic analyses of haloarchaeoviruses. What emerges is that some haloarchaeoviruses possess unique morphological and life cycle properties, while others share features with other viruses (e.g., bacteriophages. Their interactions with hosts influence community structure and evolution of populations that exist in hypersaline environments as diverse as seawater evaporation ponds, to hot desert or Antarctic lakes. The discoveries of their wide-ranging and important roles in the ecology and evolution of hypersaline communities serves as a strong motivator for future investigations of both laboratory-model and environmental systems.
Luk, Alison W S; Williams, Timothy J; Erdmann, Susanne; Papke, R Thane; Cavicchioli, Ricardo
In hypersaline environments, haloarchaea (halophilic members of the Archaea) are the dominant organisms, and the viruses that infect them, haloarchaeoviruses are at least ten times more abundant. Since their discovery in 1974, described haloarchaeoviruses include head-tailed, pleomorphic, spherical and spindle-shaped morphologies, representing Myoviridae, Siphoviridae, Podoviridae, Pleolipoviridae, Sphaerolipoviridae and Fuselloviridae families. This review overviews current knowledge of haloarchaeoviruses, providing information about classification, morphotypes, macromolecules, life cycles, genetic manipulation and gene regulation, and host-virus responses. In so doing, the review incorporates knowledge from laboratory studies of isolated viruses, field-based studies of environmental samples, and both genomic and metagenomic analyses of haloarchaeoviruses. What emerges is that some haloarchaeoviruses possess unique morphological and life cycle properties, while others share features with other viruses (e.g., bacteriophages). Their interactions with hosts influence community structure and evolution of populations that exist in hypersaline environments as diverse as seawater evaporation ponds, to hot desert or Antarctic lakes. The discoveries of their wide-ranging and important roles in the ecology and evolution of hypersaline communities serves as a strong motivator for future investigations of both laboratory-model and environmental systems. PMID:25402735
Basta, T.; Garrett, Roger Antony; Prangishvili,, David
Double-stranded deoxyribonucleic acid (DNA) viruses that infect members of the third domain of life, the Archaea, are diverse and exceptional in both their morphotypes and their genomic properties. The majority of characterized species infect hyperthermophilic hosts and carry morphological features...
Kjær, Peter; Frankel, Christian
concrete management knowledge and practice. The article isstructured as follows. After the introduction, we first develop the notion of organizational virus asinto an analytical approach. Second, we discern in the work of Frederick Taylor on scientificmanagement and Max Weber on bureaucracy, two quite...
Zeijl, J.H. van
We conclude that viral infections are the main cause of febrile seizures, with an important role for influenza A, HHV-6 and HHV-7. We showed that several viral infections not only contribute to initial febrile seizures, but also to recurrences. Viruses could not be detected in the CSF of children wi
Savithri, HS; Murthy, MRN
The amino acid sequences of the non-structural protein (molecular weight 35,000; 3a protein) from three plant viruses - cucumber mosaic, brome mosaic and alfalfa mosaic have been systematically compared using the partial genomic sequences for these three viruses already available. The 3a protein of cucumber mosaic virus has an amino acid sequence homology of 33.7% with the corresponding protein of brome mosaic virus. A similar protein from alfalfa mosaic virus has a homology of 18.2% and 14.2...
Full Text Available Acute respiratory illness (ARI due to various viruses is not only the most common cause of upper respiratory infection in humans but is also a major cause of morbidity and mortality, leading to diseases such as bronchiolitis and pneumonia. Previous studies have shown that respiratory syncytial virus (RSV, human rhinovirus (HRV, human metapneumovirus (HMPV, human parainfluenza virus (HPIV, and human enterovirus (HEV infections may be associated with virus-induced asthma. For example, it has been suggested that HRV infection is detected in the acute exacerbation of asthma and infection is prolonged. Thus it is believed that the main etiological cause of asthma is ARI viruses. Furthermore, the number of asthma patients in most industrial countries has greatly increased, resulting in a morbidity rate of around 10-15% of the population. However, the relationships between viral infections, host immune response, and host factors in the pathophysiology of asthma remain unclear. To gain a better understanding of the epidemiology of virus-induced asthma, it is important to assess both the characteristics of the viruses and the host defense mechanisms. Molecular epidemiology enables us to understand the pathogenesis of microorganisms by identifying specific pathways, molecules, and genes that influence the risk of developing a disease. However, the epidemiology of various respiratory viruses associated with virus-induced asthma is not fully understood. Therefore, in this article, we review molecular epidemiological studies of RSV, HRV, HPIV, and HMPV infection associated with virus-induced asthma.
Nataša Duduk; Aleksandra Bulajić; Janoš Berenji; Ivana Đekić; Bojan Duduk; Branka Krstić
Infection with a large number of plant viruses could imperil tobacco yield and quality. Tobacco is a natural host for more than 20 viruses, among which the most important and economically harmful are tobacco mosaic virus (TMV), tomato spotted wilt virus (TSWV), cucumber mosaic virus (CMV), potato virus Y (PVY), alfalfa mosaic virus (AMV), tobacco ringspot virus (TRSV), tobacco each virus (TEV) and tobacco vein mottling virus (TVMV).The occurence and distribution of tobacco viruses were invest...
Lisa Zeigler Allen
Full Text Available Whole genome amplification and sequencing of single microbial cells has significantly influenced genomics and microbial ecology by facilitating direct recovery of reference genome data. However, viral genomics continues to suffer due to difficulties related to the isolation and characterization of uncultivated viruses. We report here on a new approach called 'Single Virus Genomics', which enabled the isolation and complete genome sequencing of the first single virus particle. A mixed assemblage comprised of two known viruses; E. coli bacteriophages lambda and T4, were sorted using flow cytometric methods and subsequently immobilized in an agarose matrix. Genome amplification was then achieved in situ via multiple displacement amplification (MDA. The complete lambda phage genome was recovered with an average depth of coverage of approximately 437X. The isolation and genome sequencing of uncultivated viruses using Single Virus Genomics approaches will enable researchers to address questions about viral diversity, evolution, adaptation and ecology that were previously unattainable.
Kim, Kenneth; Shresta, Sujan
The Centers for Disease Control and Prevention has confirmed that Zika virus (ZIKV) causes congenital microcephaly. ZIKV now joins five other neuroteratogenic (NT) viruses in humans and ZIKV research is in its infancy. In addition, there is only one other NT human arbovirus (Venezuelan equine encephalitis virus), which is also poorly understood. But further insight into ZIKV can be found by evaluating arboviruses in domestic animals, of which there are at least seven NT viruses, three of which have been well studied. Here we review two key anatomical structures involved in modeling transplacental NT virus transmission: the placenta and the fetal blood-brain barrier. We then survey major research findings regarding transmission of NT viruses for guidance in establishing a mouse model of Zika disease that is crucial for a better understanding of ZIKV transmission and pathogenesis. PMID:27387029
... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Bovine Virus Diarrhea Vaccine, Killed... REQUIREMENTS Killed Virus Vaccines § 113.215 Bovine Virus Diarrhea Vaccine, Killed Virus. Bovine Virus Diarrhea... paragraph. (i) Eight bovine virus diarrhea susceptible calves (five vaccinates and three controls) shall...
Rapid Detection and Quantification of RNA of Ebola and Marburg Viruses, Lassa Virus, Crimean-Congo Hemorrhagic Fever Virus, Rift Valley Fever Virus, Dengue Virus, and Yellow Fever Virus by Real-Time Reverse Transcription-PCR
Drosten, Christian; Göttig, Stephan; Schilling, Stefan; Asper, Marcel; Panning, Marcus; Schmitz, Herbert; Günther, Stephan
Viral hemorrhagic fevers (VHFs) are acute infections with high case fatality rates. Important VHF agents are Ebola and Marburg viruses (MBGV/EBOV), Lassa virus (LASV), Crimean-Congo hemorrhagic fever virus (CCHFV), Rift Valley fever virus (RVFV), dengue virus (DENV), and yellow fever virus (YFV). VHFs are clinically difficult to diagnose and to distinguish; a rapid and reliable laboratory diagnosis is required in suspected cases. We have established six one-step, real-time reverse transcripti...
Yang, Tao; Li, Shugang; Zhang, Xuming; Pang, Xiaowu; Lin, Qinlu; Cao, Jianzhong
Resveratrol is a natural phenolic product found in some plants in response to stress and has been linked to the many health benefits of red wine. Over the past several decades, a great deal of research has identified diverse biological roles associated with resveratrol, including anti-oxidant, anti-proliferation, anti-inflammation, anti-cancer, anti-fungal, and antiviral activities. Such biological activities of resveratrol are likely mediated through multiple cellular targets or pathways, such as sirtuins, a family of NAD(+)-dependent deacetylases. In this treatise, the literatures focusing on the roles of resveratrol and sirtuins in modulating infections by a broad-spectrum of viruses are reviewed, with an emphasis on its potential antiviral mechanisms. A working model about the effects of resveratrol on virus infection is proposed to stimulate further researches on this exciting topic. PMID:26479742
Avec l’aide de récents résultats de la virologie, le présent article se concentre sur les virus en tant que participants d’une possible redéfinition de la frontière inférieure de la vie, en tant que vie minimale. À l’heure du triomphe de la viralité dans la cyberculture contemporaine, l’auteur avance que l’on devrait considérer les virus comme les premières formes d’entités convergentes, c’est-à-dire existant par-delà la division du monde en deux phases distinctes et incompatibles, numérique ...
de la Calle-Prieto, Fernando; Arsuaga-Vicente, Marta; Mora-Rillo, Marta; Arnalich-Fernandez, Francisco; Arribas, Jose Ramon
The first known Ebola outbreak occurred in 1976. Since then, 24 limited outbreaks had been reported in Central Africa, but never affecting more than 425 persons. The current outbreak in Western Africa is the largest in history with 28,220 reported cases and 11,291 deaths. The magnitude of the epidemic has caused worldwide alarm. For the first time, evacuated patients were treated outside Africa, and secondary cases have occurred in Spain and the United States. Since the start of the current epidemic, our knowledge about the epidemiology, clinical picture, laboratory findings, and virology of Ebola virus disease has considerably expanded. For the first time, experimental treatment has been tried, and there have been spectacular advances in vaccine development. A review is presented of these advances in the knowledge of Ebola virus disease. PMID:26774254
Full Text Available Abstract Viruses with large genomes encode numerous proteins that do not directly participate in virus biogenesis but rather modify key functional systems of infected cells. We report that a distinct group of giant viruses infecting unicellular eukaryotes that includes Organic Lake Phycodnaviruses and Phaeocystis globosa virus encode predicted proteorhodopsins that have not been previously detected in viruses. Search of metagenomic sequence data shows that putative viral proteorhodopsins are extremely abundant in marine environments. Phylogenetic analysis suggests that giant viruses acquired proteorhodopsins via horizontal gene transfer from proteorhodopsin-encoding protists although the actual donor(s could not be presently identified. The pattern of conservation of the predicted functionally important amino acid residues suggests that viral proteorhodopsin homologs function as sensory rhodopsins. We hypothesize that viral rhodopsins modulate light-dependent signaling, in particular phototaxis, in infected protists. This article was reviewed by Igor B. Zhulin and Laksminarayan M. Iyer. For the full reviews, see the Reviewers’ reports section.
A review on the geographic distribution, vectors and hosts of Bhanja virus (Bunyaviridae) is based on reports about: isolations of the virus; antibody surveys. Bhanja virus has been isolated in 15 countries of Asia, Africa and Europe, and antibodies against it have been detected in 15 additional countries. Vector range includes ticks of the family Ixodidae (subfam. Amblyomminae; not subfam. Ixodinae): 13 species of 6 genera (Haemaphysalis, Dermacentor, Hyalomma, Amblyomma, Rhipicephalus and Boophilus) yielded the virus. Bhanja virus has only rarely been isolated from vertebrates (Atelerix, Xerus, Ovis, Bos; possibly bats), though antibodies have been detected frequently in a wide range of mammals (Ruminantia being the major hosts), in several species of birds (Passeriformes, Galliformes) and even reptiles (Ophisaurus apodus). Natural foci of the Bhanja virus infections are of the boskematic type (sensu Rosický), associated closely with pastures of domestic ruminants infested by ticks in the regions of tropical, subtropical and partly temperate climatic zones. PMID:3108117
This podcast provides general information about Ebola virus disease and the outbreak in West Africa. The program contains remarks from CDC Director Dr. Tom Frieden, as well as a brief description of CDCâs response efforts. Created: 8/8/2014 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID). Date Released: 8/8/2014.
The current outbreak of Ebola virus disease (EVD) in West Africa is the largest recognized outbreak of this disease to date. It is also the first such outbreak including cases infected outside of Africa. The risk of an introduction of EVD to Germany (defined as an infected person entering Germany and passing the infection to others) is very low. But it cannot be totally excluded that in isolated instances infected persons could enter unrecognizably during the incubation period, potentiall...
Cartwright, R Y
There is no evidence to indicate that there is a risk of acquiring a virus infection through the consumption of properly treated drinking water, provided the integrity of the distribution system is maintained and there is no post-treatment contamination. The consumption of inadequately treated, untreated or post-treatment contaminated water is, however, associated with a risk of hepatitis A, hepatitis E and viral gastroenteritis. The use of the standard bacterial indicators for water monitori...
Branche, Angela R; Falsey, Ann R
Human parainfluenza viruses (HPIVs) are single-stranded, enveloped RNA viruses of the Paramyoviridaie family. There are four serotypes which cause respiratory illnesses in children and adults. HPIVs bind and replicate in the ciliated epithelial cells of the upper and lower respiratory tract and the extent of the infection correlates with the location involved. Seasonal HPIV epidemics result in a significant burden of disease in children and account for 40% of pediatric hospitalizations for lower respiratory tract illnesses (LRTIs) and 75% of croup cases. Parainfluenza viruses are associated with a wide spectrum of illnesses which include otitis media, pharyngitis, conjunctivitis, croup, tracheobronchitis, and pneumonia. Uncommon respiratory manifestations include apnea, bradycardia, parotitis, and respiratory distress syndrome and rarely disseminated infection. Immunity resulting from disease in childhood is incomplete and reinfection with HPIV accounts for 15% of respiratory illnesses in adults. Severe disease and fatal pneumonia may occur in elderly and immunocompromised adults. HPIV pneumonia in recipients of hematopoietic stem cell transplant (HSCT) is associated with 50% acute mortality and 75% mortality at 6 months. Though sensitive molecular diagnostics are available to rapidly diagnose HPIV infection, effective antiviral therapies are not available. Currently, treatment for HPIV infection is supportive with the exception of croup where the use of corticosteroids has been found to be beneficial. Several novel drugs including DAS181 appear promising in efforts to treat severe disease in immunocompromised patients, and vaccines to decrease the burden of disease in young children are in development. PMID:27486735
Today the Internet is a valuable source of information as well as a powerful communication medium, with undoubted social and economic benefits, however it also poses some security risks. Virsuses may hide in email attachments or in appartently innocent applications directly downloadable from the Internet. In this work we give a brief overview of virus types and main defense techniques. Then we present statistical data of virus attacks revealed by an anti-virus SW activated on our e-mail serve...
Kuzmin, Ivan V.; Niezgoda, Michael; Franka, Richard; Agwanda, Bernard; Markotter, Wanda; Beagley, Janet C.; Urazova, Olga Y.; Breiman, Robert F.; Rupprecht, Charles E.
During lyssavirus surveillance, 1,221 bats of at least 30 species were collected from 25 locations in Kenya. One isolate of Lagos bat virus (LBV) was obtained from a dead Eidolon helvum fruit bat. The virus was most similar phylogenetically to LBV isolates from Senegal (1985) and from France (imported from Togo or Egypt; 1999), sharing with these viruses 100% nucleoprotein identity and 99.8 to 100% glycoprotein identity. This genome conservancy across space and time suggests that LBV is well ...
... Past Newsletters Variant (Swine Origin) Influenza Viruses in Humans Language: English EspaÃ±ol Recommend on Facebook Tweet ... Page Background Reporting Additional Information Key Facts about Human Infections with Variant Viruses (Swine Origin Influenza Viruses ...
Zhang, Summer; Chan, Kuan Rong; Tan, Hwee Cheng; Ooi, Eng Eong
The early events of the dengue virus life cycle involve virus binding, internalization, trafficking, and fusion. Fluorescently labeled viruses can be used to visualize these early processes. As dengue virus has 180 identical copies of the envelope protein attached to the membrane surface and is surrounded by a lipid membrane, amine-reactive (Alexa Fluor) or lipophilic (DiD) dyes can be used for virus labeling. These dyes are highly photostable and are ideal for studies involving cellular uptake and endosomal transport. To improve virus labeling efficiency and minimize the nonspecific labeling of nonviral proteins, virus concentration and purification precede fluorescent labeling of dengue viruses. Besides using these viruses for single-particle tracking, DiD-labeled viruses can also be used to distinguish serotype-specific from cross-neutralizing antibodies. Here the details of virus concentration, purification, virus labeling, applications, and hints of troubleshooting are described. PMID:24696327
... Feed Youtube Twitter Facebook Google + iTunes Play Store Zika virus and complications: Questions and answers Online Q& ... a cause of microcephaly and Guillain-Barré syndrome. Zika virus Updated! How do people catch Zika virus? ...
Chikungunya Virus: What you need to know Chikungunya (pronunciation: \\chik-en-gun-ye) is: A virus spread through Aedes species mosquito bites. Aedes mosquitoes also spread dengue and Zika viruses. A risk to anyone traveling to a region ...
Afonso, C L; Tulman, E R; Delhon, G; Lu, Z; Viljoen, G J; Wallace, D B; Kutish, G F; Rock, D L
Here, we present the genome sequence, with analysis, of a poxvirus infecting Nile crocodiles (Crocodylus niloticus) (crocodilepox virus; CRV). The genome is 190,054 bp (62% G+C) and predicted to contain 173 genes encoding proteins of 53 to 1,941 amino acids. The central genomic region contains genes conserved and generally colinear with those of other chordopoxviruses (ChPVs). CRV is distinct, as the terminal 33-kbp (left) and 13-kbp (right) genomic regions are largely CRV specific, containing 48 unique genes which lack similarity to other poxvirus genes. Notably, CRV also contains 14 unique genes which disrupt ChPV gene colinearity within the central genomic region, including 7 genes encoding GyrB-like ATPase domains similar to those in cellular type IIA DNA topoisomerases, suggestive of novel ATP-dependent functions. The presence of 10 CRV proteins with similarity to components of cellular multisubunit E3 ubiquitin-protein ligase complexes, including 9 proteins containing F-box motifs and F-box-associated regions and a homologue of cellular anaphase-promoting complex subunit 11 (Apc11), suggests that modification of host ubiquitination pathways may be significant for CRV-host cell interaction. CRV encodes a novel complement of proteins potentially involved in DNA replication, including a NAD(+)-dependent DNA ligase and a protein with similarity to both vaccinia virus F16L and prokaryotic serine site-specific resolvase-invertases. CRV lacks genes encoding proteins for nucleotide metabolism. CRV shares notable genomic similarities with molluscum contagiosum virus, including genes found only in these two viruses. Phylogenetic analysis indicates that CRV is quite distinct from other ChPVs, representing a new genus within the subfamily Chordopoxvirinae, and it lacks recognizable homologues of most ChPV genes involved in virulence and host range, including those involving interferon response, intracellular signaling, and host immune response modulation. These data
Metamorphic viruses are considered the most dangerous of all computer viruses. Unlike other computer viruses that can be detected statically using static signature technique or dynamically using emulators, metamorphic viruses change their code to avoid such detection techniques. This makes metamorphic viruses a real challenge for computer security researchers. In this thesis, we investigate the techniques used by metamorphic viruses to alter their code, such as trivial code insertion, instruc...
Poreba, Elzbieta; Broniarczyk, Justyna Karolina; Gozdzicka-Jozefiak, Anna
About 15–20% of human cancers worldwide have viral etiology. Emerging data clearly indicate that several human DNA and RNA viruses, such as human papillomavirus, Epstein–Barr virus, Kaposi’s sarcoma-associated herpesvirus, hepatitis B virus, hepatitis C virus, and human T-cell lymphotropic virus, contribute to cancer development. Human tumor-associated viruses have evolved multiple molecular mechanisms to disrupt specific cellular pathways to facilitate aberrant replication. Although oncogeni...
While CIAC periodically issues bulletins about specific computer viruses, these bulletins do not cover all the computer viruses that affect desktop computers. The purpose of this document is to identify most of the known viruses for the MS-DOS and Macintosh platforms and give an overview of the effects of each virus. The authors also include information on some windows, Atari, and Amiga viruses. This document is revised periodically as new virus information becomes available. This document replaces all earlier versions of the CIAC Computer virus Information Update. The date on the front cover indicates date on which the information in this document was extracted from CIAC`s Virus database.
Rad, Babak Bashari; Masrom, Maslin; Ibrahim, Suhaimi
This paper presents a general overview on evolution of concealment methods in computer viruses and defensive techniques employed by anti-virus products. In order to stay far from the anti-virus scanners, computer viruses gradually improve their codes to make them invisible. On the other hand, anti-virus technologies continually follow the virus tricks and methodologies to overcome their threats. In this process, anti-virus experts design and develop new methodologies to make them stronger, mo...
Full text: Reverse genetics of negative-strand RNA viruses (NSV), which allows generation of recombinant viruses entirely from cloned cDNA, has progressed rapidly in the past decade. NSV are a large and diverse group of enveloped viruses of both medical and veterinary importance. They differ widely in morphology, genome structure and host interactions. The first NSV that was completely amenable to genetic manipulation is the neurotropathogenic rabies virus of the rhabdovirus family. In subsequent years, vesicular stomatitis virus and a number of viruses belonging to the family Paramyxoviridae, including viruses causing important animal diseases such as rinderpest virus, canine distemper virus, bovine respiratory syncytial virus, bovine parainfluenza virus and Newcastle disease virus (NDV), succumbed to genetic engineering. The ability to genetically manipulate NSV opens a wide range of possibilities to study the virus biology and develop improved vaccines. Identification and analysis of attenuating mutations using the recombinant system could lead to generation of safe vaccine strains. Introduction of one of the previously studied mutation into an infectious rabies virus (RV) clone by replacing the arginine at position 333 of RV glycoprotein (G-protein) by an aspartic acid resulted in a dramatic attenuation. Combination of this mutation with a deletion that eliminates the interaction between RV P-protein and the cytoplasmic dynein light chain (LC8), which is presumably involved in retrograde transport of RV, further attenuates the rabies virus by 30-fold after intramuscular inoculation. Since extreme attenuation may adversely affect immunogenicity, reverse genetics was used to introduce an additional Gprotein to the step-wise attenuated RV to increase its effectiveness. The resultant recombinant virus may be helpful in developing a highly safe and effective live RV vaccine for oral immunizations of animals. Reverse genetics of NSV has also helped in providing
J. Gordon Millichap
Full Text Available A Task Force established by the Brazil Ministry of Health investigated the possible association of microcephaly with Zika virus infection during pregnancy and a registry for microcephaly cases among women suspected to have had Zika virus infection during pregnancy.
We tend to regard viruses only as pathogens and thereby dismiss their crucial importance for the evolution of life. Viruses were not only the probable precursors of the first cells, but they have helped to shape and build the genomes of all species, including humans.
Millichap, J Gordon
A Task Force established by the Brazil Ministry of Health investigated the possible association of microcephaly with Zika virus infection during pregnancy and a registry for microcephaly cases among women suspected to have had Zika virus infection during pregnancy. PMID:27004142
Sáez García, Cristina
El propósito de este trabajo es hacer una revisión sobre los datos conocidos actualmente relacionados con la infección por el virus Zika y sus consecuencias a nivel neurológico en el desarrollo fetal. La prevención se vuelve esencial contra esta enfermedad: Al no existir vacuna disponible, la actuación debe centrarse en evitar la picadura del mosquito, especialmente aquellas mujeres embarazadas. Las cifras actuales de infectados, y las de bebés nacidos con microcefalia resultan...
Afonso, C. L.; Tulman, E. R.; Delhon, G.; Lu, Z.; Viljoen, G. J.; Wallace, D. B.; Kutish, G. F.; Rock, D. L.
Here, we present the genome sequence, with analysis, of a poxvirus infecting Nile crocodiles (Crocodylus niloticus) (crocodilepox virus; CRV). The genome is 190,054 bp (62% G+C) and predicted to contain 173 genes encoding proteins of 53 to 1,941 amino acids. The central genomic region contains genes conserved and generally colinear with those of other chordopoxviruses (ChPVs). CRV is distinct, as the terminal 33-kbp (left) and 13-kbp (right) genomic regions are largely CRV specific, containin...
Alfredo Seijo; Victoria Luppo; Alejandra Morales; Elisa Gancedo; Yamila Romer; Jorge Correa; Gladys Poustis; Sergio Giamperetti; Cintia Fabbri; Delia Enría
Se presenta a la consulta un hombre proveniente de la República Dominicana con una tenosinovitis del extensor del dedo medio derecho; en la convalecencia inmediata, segunda curva febril luego de 48 horas de permanecer asintomático de una enfermedad febril aguda, y marcada astenia, exantema pruriginoso, poliartralgias con impotencia funcional y rigidez articular generalizada. Los exámenes bioquímicos no aportaron datos de interés para el diagnóstico. La serología para virus dengue fue negativa...
Pedersen, N C; Yamamoto, J K; Ishida, T; Hansen, H
Feline immunodeficiency virus (FIV) (formerly feline T-lymphotropic lentivirus or FTLV) was first isolated from a group of cats in Petaluma, California in 1986. The virus is a typical lentivirus in gross and structural morphology. It replicates preferentially but not exclusively in feline T-lymphoblastoid cells, where it causes a characteristic cytopathic effect. The major structural proteins are 10, 17 (small gag), 28 (major core), 31 (endonuclease?), 41 (transmembrane?), 52 (core precursor polyprotein), 54/62 (reverse transcriptase?), and 110/130 (major envelope) kilodaltons in size. The various proteins are antigenically distinguishable from those of other lentiviruses, although serum from EIAV-infected horses will cross-react with some FIV antigens. Kittens experimentally infected with FIV manifest a transient (several days to 2 weeks) fever and neutropenia beginning 4 to 8 weeks after inoculation. This is associated with a generalized lymphadenopathy that persists for up to 9 months. Most cats recover from this initial phase of the disease and become lifelong carriers of the virus. Complete recovery does not occur to any extent in nature or in the laboratory setting. One experimentally infected cat died from a myeloproliferative disorder several months after infection. The terminal AIDS-like phase of the illness has been seen mainly in naturally infected cats. It appears a year or more following the initial infection in an unknown proportion of infected animals. FIV has been identified in cats from all parts of the world. It is most prevalent in high density populations of free roaming cats (feral and pet), and is very uncommon in closed purebred catteries. Male cats are twice as likely to become infected as females. Older male cats adopted as feral or stray animals are at the highest risk of infection, therefore. The infection rate among freely roaming cats rises throughout life, and reaches levels ranging from less than 1% to 12% or more depending on the
Hyndman, Timothy H; Shilton, Cathy M; Doneley, Robert J T; Nicholls, Philip K
Sunshine virus is a recently discovered novel paramyxovirus that is associated with illness in snakes. It does not phylogenetically cluster within either of the two currently accepted paramyxoviral subfamilies. It is therefore only distantly related to the only other known genus of reptilian paramyxoviruses, Ferlavirus, which clusters within the Paramyxovirinae subfamily. Clinical and diagnostic aspects associated with Sunshine virus are as yet undescribed. The objective of this paper was to report the clinical presentation, virus isolation, PCR testing and pathology associated with Sunshine virus infection. Clinical records and samples from naturally occurring cases were obtained from two captive snake collections and the archives of a veterinary diagnostic laboratory. The clinical signs that are associated with Sunshine virus infection are localised to the neurorespiratory systems or are non-specific (e.g. lethargy, inappetence). Out of 15 snakes that were infected with Sunshine virus (detected in any organ by either virus isolation or PCR), the virus was isolated from four out of ten (4/10) sampled brains, 3/10 sampled lungs and 2/7 pooled samples of kidney and liver. In these same 15 snakes, PCR was able to successfully detect Sunshine virus in fresh-frozen brain (11/11), kidney (7/8), lung (8/11) and liver (5/8); and various formalin-fixed paraffin-embedded tissues (7/8). During a natural outbreak of Sunshine virus in a collection of 32 snakes, the virus could be detected in five out of 39 combined oral-cloacal swabs that were collected from 23 of these snakes over a 105 day period. All snakes that were infected with Sunshine virus were negative for reovirus and ferlavirus by PCR. Snakes infected with Sunshine virus reliably exhibited hindbrain white matter spongiosis and gliosis with extension to the surrounding grey matter and neuronal necrosis evident in severe cases. Five out of eight infected snakes also exhibited mild bronchointerstitial pneumonia
Prangishvili, P.; Basta, P.; Garrett, Roger Antony
not been observed among viruses from the other two domains of life, the Bacteria and the Eukarya. Also the sequences of circular and linear genomes of crenarchaeal viruses are remarkable because the vast majority of predicted genes have no homologs in the public sequence databases. Viruses of the...... demonstrated a simple transcriptional pattern with minimal temporal control. The replication of viral genomes has not been studied experimentally. Nevertheless, some plausible predictions about possible replication strategies could be made based on specific features of several viral genomes. The comparative...... genomics studies revealed that crenarchaeal viruses form a distinctive group, unrelated to any other viruses, with a small pool of shared genes and a unique origin, or more likely, multiple origins....
Fischer, Matthias G
Viruses with genomes up to a few megabases in length are a common occurrence in nature, even though they have escaped our notice until recently. These giant viruses infect mainly single-celled eukaryotes and isolation efforts concentrating on amoebal hosts alone have spawned hundreds of viral isolates, featuring viruses with previously unseen virion morphologies and the largest known viral genomes and particles. One of the challenges that lie ahead is to analyze and categorize the available data and to establish an approved classification system that reflects the evolutionary relationships and biological properties of these viruses. Extensive sampling of Acanthamoeba-infecting mimiviruses and initial characterization of their virophage parasites have provided a first blueprint of the genetic diversity and composition of a giant virus clade that will facilitate the taxonomic grouping of these fascinating microorganisms. PMID:26999382
Chahar, Harendra S; Bharaj, Preeti; Dar, Lalit; Guleria, Randeep; Kabra, Sushil K; Broor, Shobha
Aedes aegypti mosquitoes are common vectors for dengue virus and chikungunya virus. In areas where both viruses cocirculate, they can be transmitted together. During a dengue outbreak in Delhi in 2006, 17 of 69 serum samples were positive for chikungunya virus by reverse transcription–PCR; 6 samples were positive for both viruses.
Kevin J Olival; Islam, Ariful; YU, Meng; Anthony, Simon J.; Epstein, Jonathan H.; Khan, Shahneaz Ali; Khan, Salah Uddin; Crameri, Gary; Wang, Lin-Fa; Lipkin, W. Ian; Luby, Stephen P.; Daszak, Peter
To determine geographic range for Ebola virus, we tested 276 bats in Bangladesh. Five (3.5%) bats were positive for antibodies against Ebola Zaire and Reston viruses; no virus was detected by PCR. These bats might be a reservoir for Ebola or Ebola-like viruses, and extend the range of filoviruses to mainland Asia.
Nowadays viruses use polymorphic techniques to mutate their code on each replication, thus evading detection by antiviruses. However detection by emulation can defeat simple polymorphism: thus metamorphic techniques are used which thoroughly change the viral code, even after decryption. We briefly detail this evolution of virus protection techniques against detection and then study the MetaPHOR virus, today's most advanced metamorphic virus.
Savidis, George; Perreira, Jill M; Portmann, Jocelyn M; Meraner, Paul; Guo, Zhiru; Green, Sharone; Brass, Abraham L
Zika virus has emerged as a severe health threat with a rapidly expanding range. The IFITM family of restriction factors inhibits the replication of a broad range of viruses, including the closely related flaviruses West Nile virus and dengue virus. Here, we show that IFITM1 and IFITM3 inhibit Zika virus infection early in the viral life cycle. Moreover, IFITM3 can prevent Zika-virus-induced cell death. These results suggest that strategies to boost the actions and/or levels of the IFITMs might be useful for inhibiting a broad range of emerging viruses. PMID:27268505
Full Text Available Zika virus has emerged as a severe health threat with a rapidly expanding range. The IFITM family of restriction factors inhibits the replication of a broad range of viruses, including the closely related flaviruses West Nile virus and dengue virus. Here, we show that IFITM1 and IFITM3 inhibit Zika virus infection early in the viral life cycle. Moreover, IFITM3 can prevent Zika-virus-induced cell death. These results suggest that strategies to boost the actions and/or levels of the IFITMs might be useful for inhibiting a broad range of emerging viruses.
Weiss, B; Schlesinger, S
Defective interfering particles derived from wild-type Sindbis virus no longer interfere with the infectious virus cloned from BHK cells persistently infected with Sindbis virus for 16 months. These particles do interfere with the replication of Semliki Forest virus.
Full Text Available Joe Goldufsky,1 Shanthi Sivendran,3 Sara Harcharik,4 Michael Pan,4 Sebastian Bernardo,4 Richard H Stern,5 Philip Friedlander,4 Carl E Ruby,1,2 Yvonne Saenger,4 Howard L Kaufman1,2 Departments of 1Immunology & Microbiology and 2Surgery, Rush University Medical Center, Chicago IL, USA 3Hematology/Oncology Medical Specialists, Lancaster General Health, Lancaster, PA, USA, and Departments of 4Medical Oncology and 5Radiology, Tisch Cancer Institute, The Mount Sinai School of Medicine, New York, NY, USA Abstract: The use of oncolytic viruses to treat cancer is based on the selection of tropic tumor viruses or the generation of replication selective vectors that can either directly kill infected tumor cells or increase their susceptibility to cell death and apoptosis through additional exposure to radiation or chemotherapy. In addition, viral vectors can be modified to promote more potent tumor cell death, improve the toxicity profile, and/or generate host antitumor immunity. A variety of viruses have been developed as oncolytic therapeutics, including adenovirus, vaccinia virus, herpesvirus, coxsackie A virus, Newcastle disease virus, and reovirus. The clinical development of oncolytic viral therapy has accelerated in the last few years, with several vectors entering clinical trials for a variety of cancers. In this review, current strategies to optimize the therapeutic effectiveness and safety of the major oncolytic viruses are discussed, and a summary of current clinical trials is provided. Further investigation is needed to characterize better the clinical impact of oncolytic viruses, but there are increasing data demonstrating the potential promise of this approach for the treatment of human and animal cancers. Keywords: cancer, gene therapy, oncolytic therapy, virus, treatment
Nirav R. Soni
Zika virus (ZIKV) is a member of the virus family Flaviviridae and the genus Flavivirus, transmitted by daytime-active Aedes mosquitoes, such as A. aegypti. ZIKV will continue to spread and it will be difficult to determine how the virus will spread over time. Sign and symptoms of ZIKAVD (Zika virus disease) were conjunctivitis (red eyes), back pain, birth defect-abnormal brain development known as microcephaly and it is diagnosed through PCR (polymerase chain reaction) and virus isolation fr...
Xiaofan Yang; Lu-Xing Yang
Epidemic dynamics of computer viruses is an emerging discipline aiming to understand the way that computer viruses spread on networks. This paper is intended to establish a series of rational epidemic models of computer viruses. First, a close inspection of some common characteristics shared by all typical computer viruses clearly reveals the flaws of previous models. Then, a generic epidemic model of viruses, which is named as the SLBS model, is proposed. Finally, diverse generalizations of ...
In this thesis some new aspects of the infection process of nonenveloped viruses are reported. The interaction of a rod-shaped (TMV) and three spherical (CCMV, BMV, SBMV) plant viruses, of the filamentous bacteriophage M13, and of their coat proteins with membranes have been investigated. A comparison is made between the infection mechanisms of these non-enveloped viruses.1 EFFECT OF PLANT VIRUSES ON MEMBRANESAll plant viruses studied interact with membranes. This is demonstrated by turbidity...
Fauzi Adi Rafrastara; Faizal M. A.
This research proposed an architecture and a system which able to monitor the virus behavior and classify them as a traditional or polymorphic virus. Preliminary research was conducted to get the current virus behavior and to find the certain parameters which usually used by virus to attack the computer target. Finally, “test bed environment” is used to test our system by releasing the virus in a real environment, and try to capture their behavior, and followed by generating the conclusion th...
The techniques employed by viruses to avoid detection by antivirus scanners are becoming increasingly advanced. One technique commonly used by viruses to evade detection is polymorphism. The level of polymorphism in a virus indicates its ability to create different forms of itself. The use of junk instructions is a common technique to increase the level of polymorphism in a virus. Junk instructions are machine code instructions with no other function than to alter the appearance of a virus. J...
Effects of radiation on animal viruses are reviewed in terms of repair mechanisms and their possible relationship to virus transformation and carcinogenesis. Repair mechanisms are reviewed under the headings; multiplicity reactivation, photoreactivation, host-cell reactivation (dark repair), and uv reactivation. Other topics discussed are: transformation of cells in vitro by irradiated viruses, oncogenicity of virus-transformed cells in vivo, and possible role of repair mechanisms in virus transformation and oncogenesis
Lai, M M
An increasing number of animal and plant viruses have been shown to undergo RNA-RNA recombination, which is defined as the exchange of genetic information between nonsegmented RNAs. Only some of these viruses have been shown to undergo recombination in experimental infection of tissue culture, animals, and plants. However, a survey of viral RNA structure and sequences suggests that many RNA viruses were derived form homologous or nonhomologous recombination between viruses or between viruses ...
Saiz, Juan-Carlos; Vázquez-Calvo, Ángela; Blázquez, Ana B.; Merino-Ramos, Teresa; Escribano-Romero, Estela; Martín-Acebes, Miguel A.
Since the beginning of this century, humanity has been facing a new emerging, or re-emerging, virus threat almost every year: West Nile, Influenza A, avian flu, dengue, Chikungunya, SARS, MERS, Ebola, and now Zika, the latest newcomer. Zika virus (ZIKV), a flavivirus transmitted by Aedes mosquitoes, was identified in 1947 in a sentinel monkey in Uganda, and later on in humans in Nigeria. The virus was mainly confined to the African continent until it was detected in south-east Asia the 1980’s...
Juan-Carlos eSaiz; Angela eVazquez-Calvo; Ana Belen Blazquez; Teresa eMerino-Ramos; Estela eEscribano-Romero; Martín-Acebes, Miguel A.
Since the beginning of this century, humanity has been facing a new emerging, or re-emerging, virus threat almost every year: West Nile, Influenza A, avian flu, dengue, Chikungunya, SARS, MERS, Ebola, and now Zika, the latest newcomer. Zika virus (ZIKV), a flavivirus transmitted by Aedes mosquitoes, was identified in 1947 in a sentinel monkey in Uganda, and later on in humans in Nigeria. The virus was mainly confined to the African continent until it was detected in south-east Asia the 1980´s...
Kristina Maria Schmidt
Full Text Available The highly pathogenic Marburg virus (MARV is a member of the Filoviridae family and belongs to the group of nonsegmented negative-strand RNA viruses. Reverse genetics systems established for MARV have been used to study various aspects of the viral replication cycle, analyze host responses, image viral infection, and screen for antivirals. This article provides an overview of the currently established MARV reverse genetic systems based on minigenomes, infectious virus-like particles and full-length clones, and the research that has been conducted using these systems.
<正>Over the last several years,major efforts have been expended to study viral infection of honeybees mainly due to colony losses around the world(Allen M,et al.,1996).It seems that honeybees are infected with numerous viruses mounting to 18so far.Infection may be asymptomatic but could still have adverse effects on the bee and may even cause death resulting in colony collapse.Sacbrood virus(SBV)is the most widely distributed of all honey bee viruses.
Ikhsan, Laode Muhammad
Model of the dynamics of HIV infection with the mutan virus and the Immune System is a mathematical model that describes the interactions between healthy T cells, in infected cells, and the HIV virus. The models obtained three equilibrium points, which has an endemic equilibrium point and the point of equilibrium without the disease. By doing stability analysis, the stability of the equilibrium point has obtained depends on the model of the basic reproduction number (R01 dan R02). For the...
Martinelle, Ludovic; Haegeman, Andy; Lignereux, Louis; Chaber, Anne-Lise; Dal Pozzo, Fabiana; De Leeuw, Ilse; De Clercq, Kris; Saegerman, Claude
Objective: Following reintroduction and conservation programs of the Arabian oryx (Oryx leucoryx) and the scimitar horned oryx (SHO, Oryx dammah) in the United Arab Emirates (UAE), import of animals from wild game ranches in the United States of America (USA) is not uncommon. Bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV) are orbiviruses that are the causative agents of bluetongue disease (BT) and epizootic hemorrhagic disease (EHD), respectively. BTV and EHDV are en...
de Laval, F; Leparc-Goffart, I; Meynard, J-B; Daubigny, H; Simon, F; Briolant, S
Since its discovery in 1947 in Uganda, the Zika virus (ZIKV) remained in the shadows emerging in 2007 in Micronesia, where hundreds of dengue-like syndromes were reported. Then, in 2013-2014, it was rife in French Polynesia, where the first neurological effects were observed. More recently, its arrival in Brazil was accompanied by an unusually high number of children with microcephaly born to mothers infected with ZIKV during the first trimester of pregnancy. In 2016, the World Health Organization declared ZIKV infection to be a public health emergency and now talks about a ZIKV pandemic. This review aims to summarize the current knowledge about ZIKV infection, successively addressing its transmission, epidemiology, clinical aspects, diagnosis, treatment, and prevention before discussing some perspectives. PMID:27412976
Shivale Saurabh Anandrao
Full Text Available Traditionally, "Cryptography" is a benediction to information processing and communications, it helps people to store information securely and the private communications over long distances. Cryptovirology is the study of applications of cryptography to build the malicious software. It is an investigation, how modern cryptographic tools and paradigms can be used to strengthen, develop and improve new malicious software attacks. Cryptovirology attacks have been categorized as : give malware enhanced privacy andbe more robust against reverse-engineering, secondly give the attacker enhanced anonymity while communicating with deployed malware. This paper presents the idea of ``Cryptovirology'' which introduce a twist on how cryptography can also be used offensively. Being offensive means, it can be used to mount extortion based attacks that cause loss of access to information, loss of confidentiality, and information leakage, tasks which cryptography usually prevents. Also analyze threats and attacks that misuse of cryptography can cause when combined with fraudulent software (viruses, Trojans. Public-keycryptography is very essential for the attacks that based on cryptovirology. This paper also suggest some of the countermeasures, mechanisms to cope with and prevent such attacks. Even if the attackers actions on the host machine are being monitored, it still cannot be proven beyond reasonable doubt that he or she is the attacker; and it is an “originator-concealing attack”. Evidence should be collected from the “author’s own system which was used for the attack”. These attacks have implications on how the use ofcryptographic tools and techniques should be audited and managed in general purpose computing environments, and imply that access to the cryptographic tools should be in well control of the system(such as API routines. The experimental virus would demonstrate how cryptographic packages can be packed into a small space, which may
Gonçalves Manuel AFV
Full Text Available Abstract The initial discovery of adeno-associated virus (AAV mixed with adenovirus particles was not a fortuitous one but rather an expression of AAV biology. Indeed, as it came to be known, in addition to the unavoidable host cell, AAV typically needs a so-called helper virus such as adenovirus to replicate. Since the AAV life cycle revolves around another unrelated virus it was dubbed a satellite virus. However, the structural simplicity plus the defective and non-pathogenic character of this satellite virus caused recombinant forms to acquire centre-stage prominence in the current constellation of vectors for human gene therapy. In the present review, issues related to the development of recombinant AAV (rAAV vectors, from the general principle to production methods, tropism modifications and other emerging technologies are discussed. In addition, the accumulating knowledge regarding the mechanisms of rAAV genome transduction and persistence is reviewed. The topics on rAAV vectorology are supplemented with information on the parental virus biology with an emphasis on aspects that directly impact on vector design and performance such as genome replication, genetic structure, and host cell entry.
Copeland, N G; Cooper, G M
Chicken embryo fibroblasts and NIH 3T3 mouse cells were transformable by DNAs of chicken cells infected with avian myelocytomatosis virus strain MC29 or with avian erythroblastosis virus. Transfection of chicken cells appeared to require replication of MC29 or avian erythroblastosis virus in the presence of a nontransforming helper virus. In contrast, NIH 3T3 cells transformed by MC29 or avian erythroblastosis virus DNA contained only replication-defective transforming virus genomes.
Ecker, J R; Hyman, R W
The DNAs of a varicella-zoster virus vaccine and its parental virus were compared by CsCl buoyant density centrifugation and restriction enzyme cleavage analysis. The varicella-zoster virus vaccine DNA showed a heterogeneous buoyant profile and altered restriction enzyme cleavage patterns. These changed properties are probably the result of the accumulation of virus containing defective varicella-zoster virus DNA during extensive cell culture passage of the vaccine virus.
Rhim, J S; Trimmer, R; Arnstein, P; Huebner, R J
The adenovirus 12--simian virus 40 hybrid virus produced neoplastic transformation of chimpanzee skin fibroblasts in vitro. The transformed fibroblasts showed morphological alteration and became permanent lines. The transformed cells contained both adenovirus 12 and simian virus 40 large tumor antigens and were virus producers. However at passage 9, one line (WES) was found to be a nonproducer, producing neither infectious virus nor virus-specific antigen detectable by the complement fixation...
Foley, Heather D.; McGettigan, James P.; Siler, Catherine A.; Dietzschold, Bernhard; Schnell, Matthias J.
To investigate the importance of the rabies virus (RV) glycoprotein (G) in protection against rabies, we constructed a recombinant RV (rRV) in which the RV G ecto- and transmembrane domains were replaced with the corresponding regions of vesicular stomatitis virus (VSV) glycoprotein (rRV-VSV-G). We were able to recover rRV-VSV-G and found that particle production was equal to rRV. However, the budding of the chimeric virus was delayed and infectious titers were red...
Erdmann, Susanne; Garrett, Roger Antony
Infection of archaea with phylogenetically diverse single viruses, performed in different laboratories, has failed to activate spacer acquisition into host CRISPR loci. The first successful uptake of archaeal de novo spacers was observed on infection of Sulfolobus solfataricus P2 with an environm......Infection of archaea with phylogenetically diverse single viruses, performed in different laboratories, has failed to activate spacer acquisition into host CRISPR loci. The first successful uptake of archaeal de novo spacers was observed on infection of Sulfolobus solfataricus P2 with an...... CRISPR loci of Sulfolobus species from a second coinfecting conjugative plasmid or virus (Erdmann and Garrett, Mol Microbiol 85:1044-1056, 2012; Erdmann et al. Mol Microbiol 91:900-917, 2014). Here we describe, firstly, the isolation of archaeal virus mixtures from terrestrial hot springs and the...
Palomo, Adolfo Martinez
This Viewpoint discusses the World Health Organization's Declaration on 1 February 2016 that the epidemic infection caused by the Zika virus is a public health emergency of international concern - the basis of the decision and controversy surrounding it. PMID:26911655
Oncolytic viruses are investigational cancer treatments. They are currently being assessed as single agents or in combination with standard therapies such as external beam radiotherapy - a DNA damaging agent that is a standard of care for many tumour types. Preclinical data indicate that combinations of oncolytic viruses and radiation therapy are promising, showing additional or synergistic antitumour effects in in vitro and in vivo studies. This interaction has the potential to be multifaceted: viruses may act as radiosensitizing agents, but radiation may also enhance viral oncolysis by increasing viral uptake, replication, gene expression and cell death (apoptosis, autophagy or necrosis) in irradiated cells. Phase I and II clinical trials investigating combinations of viruses and radiation therapy have been completed, paving the way for ongoing phase III studies. The aim of this review is to focus on the therapeutic potential of these combinations and to highlight their mechanistic bases, with particular emphasis on the role of the DNA damage response.
Amarasinghe, Ananda; Kuritsky, Joel N.; Letson, G. William; Margolis, Harold S
Reported incidence of dengue has increased worldwide in recent decades, but little is known about its incidence in Africa. During 1960–2010, a total of 22 countries in Africa reported sporadic cases or outbreaks of dengue; 12 other countries in Africa reported dengue only in travelers. The presence of disease and high prevalence of antibody to dengue virus in limited serologic surveys suggest endemic dengue virus infection in all or many parts of Africa. Dengue is likely underrecognized and u...
During the past decade there has been extraordinary progress toward the development of vaccines for the prevention of type A and type B hepatitis. The successful propagation of hepatitis A virus in cell culture in 1979 was followed by the preparation of experimental live attenuated hepatitis A vaccines that have been shown to induce antibody in marmosets and chimpanzees and protect immunized marmosets against challenge with hepatitis A virus. The first human immunization trials will begin in ...
Hendra virus, a novel member of the family Paramyxovirus that has emerged from bats in Australia, causes fatal disease in livestock and humans. Eleven spillover events have been identified since the first description of the virus in 1994, resulting in a total of 37 equine cases and six human cases. All human cases have been attributed to exposure to infected horses; there is no evidence of bat-to-human or human-to-human transmission. Low infectivity and a high case fatality rate are features of Hendra virus infection in both horses and humans. The temporal pattern of spillover events suggests seasonal factors (plausibly be environmental, biological or ecological) as the proximate triggers for spillover. Minimisation of the future occurrence and impact of Hendra virus infections requires an understanding of the ecology of flying foxes, of virus infection dynamics in flying foxes, and of the factors that promote spillover. Management strategies seek to minimize the opportunity for effective contact between bats and horses, and limit potential horse-to-horse and horse-to-human transmission. Incomplete knowledge of the ecology of the virus, of the proximate factors associated with spillover, and the inherent difficulties of effectively managing wild populations, preclude a management approach targeted at bats.
... Frequently asked questions Updated: 25 March 2016 ABOUT ZIKA What is Zika virus infection? Zika virus infection is caused by ... possible to characterize the disease better. How is Zika virus transmitted? Zika virus is transmitted to people ...
George Savidis; Jill M. Perreira; Jocelyn M. Portmann; Paul Meraner; Zhiru Guo; Sharone Green; Abraham L. Brass
Zika virus has emerged as a severe health threat with a rapidly expanding range. The IFITM family of restriction factors inhibits the replication of a broad range of viruses, including the closely related flaviruses West Nile virus and dengue virus. Here, we show that IFITM1 and IFITM3 inhibit Zika virus infection early in the viral life cycle. Moreover, IFITM3 can prevent Zika-virus-induced cell death. These results suggest that strategies to boost the actions and/or levels of the IFITMs mig...
Garlic virus infection is an important disease which affects garlic production,with the increasing years of planting,harm of virus is serious year by year,which seriously affect yield and quality of garlic.In order to know the garlic virus effectively,the paper reviewed the research situation of several important garlic virus in virus species,origin,distribution,host range,symptom,route of transmission,classification,genome and detection technique and the prevention technology of garlic viruses.At the same ...
ShanXiuming; LiYing; JiaoJian; LiuYang; RenYong; QiuBen; CaoYiqun
The computer network is not only of benefit to people, but also helpful for the spreading of viruses. The net-viruses spread more widely and rapidly than the traditional viruses, and network has become the major path of the virus spreading. The author analyzes the mode of the net-virus spreading, including E-mail spreading, positive scanning spreading and through-server spreading. Then some defense strategies in the anti-virus field are introduced, and some countermeasures of the net computer users are discussed.
McClurkin, A W.; Littledike, E T; Cutlip, R C; Frank, G H; Coria, M F; Bolin, S R
Inoculation of bovine virus diarrhea virus into 58 to 125 day old fetuses of bovine virus diarrhea virus seropositive pregnant cows, or inoculation of bovine virus diarrhea virus into seronegative cows 42 to 114 days pregnant, may produce clinically normal calves which are persistently infected with the specific isolate of bovine virus diarrhea virus yet seronegative to the homologous and heterologous isolates. Reinoculation of these persistently infected cattle with their homologous isolate ...
Jelena Zindović; Nataša Dukić; Aleksandra Bulajić; Jelena Latinović; Ivana Đekić; Bojan Duduk; Branka Krstić
Seven important tobacco viruses were investigated in Montenegro in 2005: Tobacco Mosaic Virus (TMV), Tomato Spotted Wilt Virus (TSWV), Cucumber Mosaic Virus (CMV), Potato Virus Y (PVY), Alfalfa Mosaic Virus (AMV), Tobacco Ring Spot Virus (TRSV) and Potato Virus X(PVX). This investigation included sample collection from four tobacco growing regions in Montenegro and their serological testing by DAS-ELISA test. Presence of different strains of PVY was investigated as well using DAS ELISA test w...
Garry Robert F
Full Text Available Abstract Viral fusion proteins mediate cell entry by undergoing a series of conformational changes that result in virion-target cell membrane fusion. Class I viral fusion proteins, such as those encoded by influenza virus and human immunodeficiency virus (HIV, contain two prominent alpha helices. Peptides that mimic portions of these alpha helices inhibit structural rearrangements of the fusion proteins and prevent viral infection. The envelope glycoprotein (E of flaviviruses, such as West Nile virus (WNV and dengue virus (DENV, are class II viral fusion proteins comprised predominantly of beta sheets. We used a physio-chemical algorithm, the Wimley-White interfacial hydrophobicity scale (WWIHS 1 in combination with known structural data to identify potential peptide inhibitors of WNV and DENV infectivity that target the viral E protein. Viral inhibition assays confirm that several of these peptides specifically interfere with target virus entry with 50% inhibitory concentration (IC50 in the 10 μM range. Inhibitory peptides similar in sequence to domains with a significant WWIHS scores, including domain II (IIb, and the stem domain, were detected. DN59, a peptide corresponding to the stem domain of DENV, inhibited infection by DENV (>99% inhibition of plaque formation at a concentrations of 99% inhibition at
Thomsen, Allan Randrup; Volkert, M; Bro-Jørgensen, K
The immunological effector mechanism responsible for the elimination of virus in murine acute non-fatal extracranial lymphocytic choriomeningitis virus infection was studied. In this infection virus clearance is generally regarded as the result of a direct action of virus-specific cytotoxic T cells...... (Tc cells) on virus-producing target cells in the infected mouse. However, by manipulating the antiviral immune response by pretreatment with various doses of cyclophosphamide, we found lack of correlation between Tc-cell activity and the clearance of virus. In contrast, we observed a conspicuous...... correlation between the host's ability to mount a virus-specific delayed-type hypersensitivity (DTH) response and its capacity to combat virus. Moreover, pretreatment with silica and carrageenan prolonged viraemia without impairment of the peak Tc-cell response. These findings indicate that Tc cells have...
CERN Medical Service
The CERN Medical Service has been closely following, in particular via the WHO, the development of the Ebola virus outbreak currently affecting some African countries. This infectious disease may be passed on through direct contact with the bodily fluids of a sick person. Based on the recommendations of the WHO and the two Host States, Switzerland and France, as updated on their respective websites, so far there has been no ban on travel to the countries concerned. However, unless it is absolutely essential, you are advised not to visit any of the countries affected by Ebola (Guinea, Republic of Sierra Leone, Liberia, Nigeria). The two Host States have established an alert system, and a check is carried out on departure from the airports of those countries. It is strongly recommended that you contact the Medical Service if you are travelling to those countries. We remind you to observe the basic rules of hygiene such as frequent hand washing, whatever your destination. The Medical Service is...
Hepadnaviruses, including human hepatitis B virus (HBV), replicate through reverse transcription of an RNA intermediate, the pregenomic RNA (pgRNA). Despite this kinship to retroviruses, there are fundamental differences beyond the fact that hepadnavirions contain DNA instead of RNA. Most peculiar is the initiation of reverse transcription: it occurs by protein-priming, is strictly committed to using an RNA hairpin on the pgRNA,ε, as template, and depends on cellular chaperones;moreover, proper replication can apparently occur only in the specialized environment of intact nucleocapsids.This complexity has hampered an in-depth mechanistic understanding. The recent successful reconstitution in the test tube of active replication initiation complexes from purified components, for duck HBV (DHBV),now allows for the analysis of the biochemistry of hepadnaviral replication at the molecular level. Here we review the current state of knowledge at all steps of the hepadnaviral genome replication cycle, with emphasis on new insights that turned up by the use of such cellfree systems. At this time, they can, unfortunately,not be complemented by three-dimensional structural information on the involved components. However, at least for the s RNA element such information is emerging,raising expectations that combining biophysics with biochemistry and genetics will soon provide a powerful integrated approach for solving the many outstanding questions. The ultimate, though most challenging goal,will be to visualize the hepadnaviral reverse transcriptase in the act of synthesizing DNA, which will also have strong implications for drug development.
The hepatitis B virus (HBV) particle consists of an envelope containing three related surface proteins and probably lipid and an icosahedral nucleocapsid of approximately 30 nm diameter enclosing the viral DNA genome and DNA polymerase. The capsid is formed in the cytosol of the infected cell during packaging of an RNA pregenome replication complex by multiple copies of a 21-kDa C protein. The capsid gains the ability to bud during synthesis of the viral DNA genome by reverse transcription of the pregenome in the lumen of the particle. The three envelope proteins S,M, and L shape a complex transmembrane fold at the endoplasmic reticulum, and form disulfide-linked homoand heterodimers. The transmembrane topology of a fraction of the large envelope protein L changes posttranslationally, therefore, the N terminal domain of L (preS) finally appears on both sides of the membrane.During budding at an intracellular membrane, a short linear domain in the cytosolic preS region interacts with binding sites on the capsid surface. The virions are subsequently secreted into the blood. In addition, the surface proteins can bud in the absence of capsids and form subviral lipoprotein particles of 20 nm diameter which are also secreted.
Buonaguro, Franco Maria; Tornesello, Maria Lina; Izzo, Francesco; Buonaguro, Luigi
Oncolytic virus (OV) therapy currently represents one of the most promising approaches to cancer treatment for their dual anticancer mechanisms: direct lysis of cancer cells (oncolytic feature) and activation of the immunosystem (cancer vaccine aspect). The latter demonstrates the advantage of a multi-target approach against multiple tumor-associated antigens. Since the 2005 SFDA (the Chinese FDA) approval for the clinical use of Oncorine™, the first human OV-based cancer treatment, more than 200 patents have been filed worldwide and several Phase I/II studies have been conducted. This patent review analyzes patents and clinical studies of the most promising OV products to highlight the pros and cons of this innovative anticancer approach, which is currently being tested in several cancers (i.e., hepatocellular carcinoma, melanoma and glioblastoma) by systemic as well as intratumoral injection. Clinical results, although effective only for a limited period of time, are encouraging. Combined treatments with radio or chemotherapeutic protocols are also in progress. PMID:24236929
TAN Ying; ZHANG Pengtao
The computer virus is considered one of the most horrifying threats to the security of computer systems worldwide.The rapid development of evasion techniques used in virus causes the signature based computer virus detection techniques to be ineffective.Many novel computer virus detection approaches have been proposed in the past to cope with the ineffectiveness,mainly classified into three categories:static,dynamic and heuristics techniques.As the natural similarities between the biological immune system (BIS),computer security system (CSS),and the artificial immune system (AIS) were all developed as a new prototype in the community of anti-virus research.The immune mechanisms in the BIS provide the opportunities to construct computer virus detection models that are robust and adaptive with the ability to detect unseen viruses.In this paper,a variety of classic computer virus detection approaches were introduced and reviewed based on the background knowledge of the computer virus history.Next,a variety of immune based computer virus detection approaches were also discussed in detail.Promising experimental results suggest that the immune based computer virus detection approaches were able to detect new variants and unseen viruses at lower false positive rates,which have paved a new way for the anti-virus research.
Autophagy is a cellular response against stresses which include the infection of viruses and bacteria. We unravel that Dengue virus-2 (DV2) can trigger autophagic process in various infected cell lines demonstrated by GFP-LC3 dot formation and increased LC3-II formation. Autophagosome formation was also observed under the transmission electron microscope. DV2-induced autophagy further enhances the titers of extracellular and intracellular viruses indicating that autophagy can promote viral replication in the infected cells. Moreover, our data show that ATG5 protein is required to execute DV2-induced autophagy. All together, we are the first to demonstrate that DV can activate autophagic machinery that is favorable for viral replication
With more than 1 200 species, bats and flying foxes (Order Chiroptera) constitute the most important and diverse order of Mammals after Rodents. Many species of bats are insectivorous while others are frugivorous and few of them are hematophagous. Some of these animals fly during the night, others are crepuscular or diurnal. Some fly long distances during seasonal migrations. Many species are colonial cave-dwelling, living in a rather small home range while others are relatively solitary. However, in spite of the importance of bats for terrestrial biotic communities and ecosystem ecology, the diversity in their biology and lifestyles remain poorly known and underappreciated. More than sixty viruses have been detected or isolated in bats; these animals are therefore involved in the natural cycles of many of them. This is the case, for instance, of rabies virus and other Lyssavirus (Family Rhabdoviridae), Nipah and Hendra viruses (Paramyxoviridae), Ebola and Marburg viruses (Filoviridae), SARS-CoV and MERS-CoV (Coronaviridae). For these zoonotic viruses, a number of bat species are considered as important reservoir hosts, efficient disseminators or even directly responsible of the transmission. Some of these bat-borne viruses cause highly pathogenic diseases while others are of potential significance for humans and domestic or wild animals; so, bats are an important risk in human and animal public health. Moreover, some groups of viruses developed through different phylogenetic mechanisms of coevolution between viruses and bats. The fact that most of these viral infections are asymptomatic in bats has been observed since a long time but the mechanisms of the viral persistence are not clearly understood. The various bioecology of the different bat populations allows exchange of virus between migrating and non-migrating conspecific species. For a better understanding of the role of bats in the circulation of these viral zoonoses, epidemiologists must pay attention to
Discusses computer viruses that attack the Macintosh and describes Symantec AntiVirus for Macintosh (SAM), a commercial program designed to detect and eliminate viruses; sample screen displays are included. SAM is recommended for use in library settings as well as two public domain virus protection programs. (four references) (MES)
F. Condorelli; Ziegler, T.
A dot immunobinding assay was used to detect antibodies to measles virus, mumps virus, and rubella virus antigens. Filter paper soaked with serum or whole blood was directly applied to the antigen-coated nitrocellulose sheets. The test was easy to perform, and its results agreed very well with those obtained by standard enzyme immunoassay.
Rotem, Assaf; Cockrell, Shelley; Guo, Mira; Pipas, James; Weitz, David
The ability to detect, isolate, and characterize an infectious agent is important for diagnosing and curing infectious diseases. Detecting new viral diseases is a challenge because the number of virus particles is often low and/or localized to a small subset of cells. Even if a new virus is detected, it is difficult to isolate it from clinical or environmental samples where multiple viruses are present each with very different properties. Isolation is crucial for whole genome sequencing because reconstructing a genome from fragments of many different genomes is practically impossible. We present a Droplet Microfluidics platform that can detect, isolate and sequence single viral genomes from complex samples containing mixtures of many viruses. We use metagenomic information about the sample of mixed viruses to select a short genomic sequence whose genome we are interested in characterizing. We then encapsulate single virions from the same sample in picoliter volume droplets and screen for successful PCR amplification of the sequence of interest. The selected drops are pooled and their contents sequenced to reconstruct the genome of interest. This method provides a general tool for detecting, isolating and sequencing genetic elements in clinical and environmental samples.
... 158128.html Scientists Try to Stop Another Deadly Virus Junin, an Ebola-like disease in Argentina, has ... drug could offer a new weapon against the virus that causes Argentine hemorrhagic fever -- a potentially fatal ...
Plourde, Anna R; Bloch, Evan M
Zika virus is a mosquitoborne flavivirus that is the focus of an ongoing pandemic and public health emergency. Previously limited to sporadic cases in Africa and Asia, the emergence of Zika virus in Brazil in 2015 heralded rapid spread throughout the Americas. Although most Zika virus infections are characterized by subclinical or mild influenza-like illness, severe manifestations have been described, including Guillain-Barre syndrome in adults and microcephaly in babies born to infected mothers. Neither an effective treatment nor a vaccine is available for Zika virus; therefore, the public health response primarily focuses on preventing infection, particularly in pregnant women. Despite growing knowledge about this virus, questions remain regarding the virus's vectors and reservoirs, pathogenesis, genetic diversity, and potential synergistic effects of co-infection with other circulating viruses. These questions highlight the need for research to optimize surveillance, patient management, and public health intervention in the current Zika virus epidemic. PMID:27070380
US Fish and Wildlife Service, Department of the Interior — Duck plague, also known as duck virus enteritis (DVE) is a highly contagious, extremely deadly epizootic virus with a potential for devastating continental...
... Research Making a Candidate Vaccine Virus Related Links Influenza Types Seasonal Avian Swine Variant Pandemic Other Get ... this? Submit What's this? Submit Button Past Newsletters Influenza Type A Viruses Language: English EspaÃ±ol Recommend ...
Bats, probably the most abundant, diverse and geographically dispersed vertebrates on earth, have recently been shown to be the reservoir hosts of a number of emerging viruses responsible for severe human and livestock disease outbreaks. Flying foxes have been demonstrated to be the natural reservoir for Hendra and Nipah viruses. Evidence supporting the possibility of bats as potential reservoirs for SARS coronavirus (SARS-CoV) and Ebola virus has also been reported. The recent discovery of these viruses and other viruses occurring naturally in the bat population provides a unique insight into a diverse pool of potentially emergent and pathogenic viruses. The factors which influence the ability of zoonotic viruses to effectively cross the species barrier from bats to other animal populations are poorly understood. A brief review is provided here on the recently emerged bat viruses and on current and future strategies for research in this area.
U.S. Department of Health & Human Services — This dataset contains positive cases of West Nile virus found in humans by county of residence, 2006-present. Humans usually become infected with West Nile virus by...
... Education Public Service Videos West Nile Virus & Dead Birds Recommend on Facebook Tweet Share Compartir On this ... dead bird sightings to local authorities. How do birds get infected with West Nile virus? West Nile ...
Kvisgaard, Lise Kirstine
This PhD thesis presents the diversity of Porcine Reproductive and Respiratory Syndrome viruses (PRRSV) circulating in the Danish pig population. PRRS is a disease in pigs caused by the PRRS virus resulting in reproductive failures in sows and gilts and respiratory diseases in pigs . Due to genetic...... heterogeneity, PRRSV is divided into two genotypes, Type 1 and Type 2. Type 1 PRRS viruses are further divided into at least 3 subtypes. The virus evolves rapidly and reports of high pathogenic variants of both Type 1 and Type 2 appearing in Europe, North America, and Asia have been reported within recent years...... viruses showed both a higher diversity to the other Danish viruses and to the vaccine strain and one virus harbored the largest deletion in NSP2 reported in Danish Type 2 PRRSV. Manuscript IV is focusing on an experimental infection study in pigs with a Type 2 PRRS virus causing significant clinical...
... nih.gov/medlineplus/news/fullstory_157799.html New Dengue Virus Vaccine Shows Promise Research may also aid ... 16, 2016 (HealthDay News) -- An experimental vaccine against dengue -- the mosquito-borne virus behind a very painful ...
... page: https://medlineplus.gov/news/fullstory_159534.html Dengue Virus May Bolster Zika's Attack Prior exposure to ... 23, 2016 (HealthDay News) -- Prior exposure to the dengue fever virus may increase the severity of Zika ...
Martin, Robert R; Tzanetakis, Ioannis E
Virus control in berry crops starts with the development of plants free of targeted pathogens, usually viruses, viroids, phytoplasmas, and systemic bacteria, through a combination of testing and therapy. These then become the top-tier plants in certification programs and are the source from which all certified plants are produced, usually after multiple cycles of propagation. In certification schemes, efforts are made to produce plants free of the targeted pathogens to provide plants of high health status to berry growers. This is achieved using a systems approach to manage virus vectors. Once planted in fruit production fields, virus control shifts to disease control where efforts are focused on controlling viruses or virus complexes that result in disease. In fruiting fields, infection with a virus that does not cause disease is of little concern to growers. Virus control is based on the use of resistance and tolerance, vector management, and isolation. PMID:25591882
Full Text Available Influenza viruses transcribe and replicate their genomes in the nuclei of infected host cells. The viral ribonucleoprotein (vRNP complex of influenza virus is the essential genetic unit of the virus. The viral proteins play important roles in multiple processes, including virus structural maintenance, mediating nucleocytoplasmic shuttling of the vRNP complex, virus particle assembly, and budding. Nucleocytoplasmic shuttling of viral proteins occurs throughout the entire virus life cycle. This review mainly focuses on matrix protein (M1, nucleoprotein (NP, nonstructural protein (NS1, and nuclear export protein (NEP, summarizing the mechanisms of their nucleocytoplasmic shuttling and the regulation of virus replication through their phosphorylation to further understand the regulation of nucleocytoplasmic shuttling in host adaptation of the viruses.
Full Text Available The past fifty years important advances have been made in the field of grapevine virus research, including characterization of pathogens and control measurements. Still the occurrence of Grapevine fanleaf virus (GFLV, Arabis mosaic virus (ArMV, Tomato black ring virus (TBRV, Grapevine chrome mosaic virus (GCMV, Alfalfa mosaic virus (AMV, Grapevine Bulgarian latent virus (GBLV, Grapevine fleck virus (GFkV, Grapevine leafroll- associated viruses (GLRaV1-4, Grapevine virus A (GVA, Grapevine virus B (GVB and Grapevine rupestris stem pitting- associated virus (GRSPaV have been reported in Hungary and characterized by conventional methods as woody indexing, herbaceous indexing and serological methods. Among grapevine viruses the Grapevine line pattern virus (GLPV seems to be uncial; because it was reported only in Hungary. Causal agents of several grapevine diseases, like enation, vein necrosis and vein mosaic remained undiscovered. These virus-like diseases occurred only sporadically, without economic importance.
Rad, Babak Bashari; Ibrahim, Suhaimi
This paper presents a general overview on evolution of concealment methods in computer viruses and defensive techniques employed by anti-virus products. In order to stay far from the anti-virus scanners, computer viruses gradually improve their codes to make them invisible. On the other hand, anti-virus technologies continually follow the virus tricks and methodologies to overcome their threats. In this process, anti-virus experts design and develop new methodologies to make them stronger, more and more, every day. The purpose of this paper is to review these methodologies and outline their strengths and weaknesses to encourage those are interested in more investigation on these areas.
Dawson, William O.; Garnsey, Stephen M.; Satyanarayana eTatineni; Folimonova, Svetlana Y.; Scott J Harper; S eGowda
Citrus tristeza virus (CTV) is a phloem-limited virus whose natural host range is restricted to citrus and related species. Although the virus has killed millions of trees, almost destroying whole industries, and continually limits production in many citrus growing areas, most isolates are mild or symptomless in most of their host range. There is little understanding of how the virus causes severe disease in some citrus and none in others. Movement and distribution of CTV differs considerably...
Muñoz-Jordán, Jorge L.; Sánchez-Burgos, Gilma G.; Laurent-Rolle, Maudry; García-Sastre, Adolfo
Dengue virus is a worldwide-distributed mosquito-borne flavivirus with a positive strand RNA genome. Its transcribed polyprotein is cleaved by host- and virus-encoded peptidases into 10 proteins, some of which are of unknown function. Although dengue virus-infected cells seem to be resistant to the antiviral action of IFN, the viral products that mediate this resistance are unknown. Therefore, we have analyzed the ability of the 10 dengue virus-encoded proteins to antagonize the IFN response....
Wickner, Reed B.; Fujimura, Tsutomu; Esteban, Rosa
Saccharomyces cerevisiae has been a key experimental organism for the study of infectious diseases, including dsRNA viruses, ssRNA viruses, and prions. Studies of the mechanisms of virus and prion replication, virus structure, and structure of the amyloid filaments that are the basis of yeast prions have been at the forefront of such studies in these classes of infectious entities. Yeast has been particularly useful in defining the interactions of the infectious elements with cellular compone...
Neu, Ursula; Bauer, Johannes; Stehle, Thilo
Viral infections are initiated by specific attachment of a virus particle to receptors at the surface of the host cell. For many viruses, these receptors are glycans that are linked to either a protein or a lipid. Glycans terminating in sialic acid and its derivatives serve as receptors for a large number of viruses, including several human pathogens. In combination with glycan array analyses, structural analyses of complexes of viruses with sialylated oligosaccharides have provided insights ...
Edward C Holmes
The increasing availability of complete genome sequences of RNA viruses has the potential to shed new light on fundamental aspects of their biology. Here, I use case studies of 3 RNA viruses to explore the impact of genomic sequence data, with particular emphasis on influenza A virus. Notably, the studies of RNA virus genomics undertaken to date largely focused on issues of evolution and epidemiology, and they have given these disciplines new impetus. However, genomic data have so far made fe...
Smith, Vincent P.; Alcami, Antonio
Ectromelia virus (EV) is an orthopoxvirus (OPV) that causes mousepox, a severe disease of laboratory mice. Mousepox is a useful model of OPV infection because EV is likely to be a natural mouse pathogen, unlike its close relatives vaccinia virus (VV) and variola virus. Several studies have highlighted the importance of mouse interferons (IFNs) in resistance to and recovery from EV infection, but little is known of the anti-IFN strategies encoded by the virus itself. We have determined that 12...
Beer, Brigitte; Kurth, Reinhard; Bukreyev, Alexander
Filoviruses are enveloped, nonsegmented negative-stranded RNA viruses. The two species, Marburg and Ebola virus, are serologically, biochemically, and genetically distinct. Marburg virus was first isolated during an outbreak in Europe in 1967, and Ebola virus emerged in 1976 as the causative agent of two simultaneous outbreaks in southern Sudan and northern Zaire. Although the main route of infection is known to be person-to-person transmission by intimate contact, the natural reservoir for filoviruses still remains a mystery.
Derbyshire, J. B.
The objective of this study was to compare the sensitivity of 11 porcine viruses to the antiviral effects of porcine interferon-alpha in serum from piglets which had been infected 19 h previously with transmissible gastroenteritis virus, and of porcine interferon-beta prepared in PK-15 cells by induction with polyinosinic:polycytidylic acid, in yield reduction assays in pig kidney cells which were treated with interferon before virus challenge, and both before and after virus challenge. The m...
Shen, Xintian; Zhang, Xuanxuan; Liu, Shuwen
Influenza virus has caused seasonal epidemics and worldwide pandemics, which caused tremendous loss of human lives and socioeconomics. Nowadays, only two classes of anti-influenza drugs, M2 ion channel inhibitors and neuraminidase inhibitors respectively, are used for prophylaxis and treatment of influenza virus infection. Unfortunately, influenza virus strains resistant to one or all of those drugs emerge frequently. Hemagglutinin (HA), the glycoprotein in influenza virus envelope, plays a c...
Salinas, Sara; Foulongne, Vincent; Loustalot, Fabien; Fournier-Wirth, Chantal; Molès, Jean-Pierre; Briant, Laurence; Nagot, Nicolas; Van de Perre, Philippe; Simonin, Yannick
Zika virus, discovered in 1947, is particularly publicized because of its involvement in a major epidemic that began in 2015 and which epicenter is located in Latin America, mainly in Brazil. In the majority of cases (70-80 %) the infection is asymptomatic, however in some patients, moderate fever, skin rash, conjunctivitis and myalgia may occur. More alarming, neurological complications are reported, in particular cases of microcephaly probably resulting from the infection of women in the first or second trimester of pregnancy. Moreover, Guillain-Barré syndromes have also been identified in patients whose infection was confirmed. The extent of the current outbreak reveals the very primitive state of knowledge about the pathophysiology of this virus. Thus, a global effort is being undertaken in order to quickly characterize the molecular interaction of the virus with human cells, but also to develop specific diagnostic assays and vaccinal approaches. PMID:27137695
Becker, Thealexa; Kontorovich, Leonid Aryeh; Miller, Steven J; Ravikumar, Pradeep; Shen, Karen
The field of epidemiology has presented fascinating and relevant questions for mathematicians, primarily concerning the spread of viruses in a community. The importance of this research has greatly increased over time as its applications have expanded to also include studies of electronic and social networks and the spread of information and ideas. We study virus propagation on a non-linear hub and spoke graph (which models well many airline networks). We determine the long-term behavior as a function of the cure and infection rates, as well as the number of spokes n. For each n we prove the existence of a critical threshold relating the two rates. Below this threshold, the virus always dies out; above this threshold, all non-trivial initial conditions iterate to a unique non-trivial steady state. We end with some generalizations to other networks.
Yugo, Danielle M; Hauck, Ruediger; Shivaprasad, H L; Meng, Xiang-Jin
Viral hepatitis in poultry is a complex disease syndrome caused by several viruses belonging to different families including avian hepatitis E virus (HEV), duck hepatitis B virus (DHBV), duck hepatitis A virus (DHAV-1, -2, -3), duck hepatitis virus Types 2 and 3, fowl adenoviruses (FAdV), and turkey hepatitis virus (THV). While these hepatitis viruses share the same target organ, the liver, they each possess unique clinical and biological features. In this article, we aim to review the common and unique features of major poultry hepatitis viruses in an effort to identify the knowledge gaps and aid the prevention and control of poultry viral hepatitis. Avian HEV is an Orthohepevirus B in the family Hepeviridae that naturally infects chickens and consists of three distinct genotypes worldwide. Avian HEV is associated with hepatitis-splenomegaly syndrome or big liver and spleen disease in chickens, although the majority of the infected birds are subclinical. Avihepadnaviruses in the family of Hepadnaviridae have been isolated from ducks, snow geese, white storks, grey herons, cranes, and parrots. DHBV evolved with the host as a noncytopathic form without clinical signs and rarely progressed to chronicity. The outcome for DHBV infection varies by the host's ability to elicit an immune response and is dose and age dependent in ducks, thus mimicking the pathogenesis of human hepatitis B virus (HBV) infections and providing an excellent animal model for human HBV. DHAV is a picornavirus that causes a highly contagious virus infection in ducks with up to 100% flock mortality in ducklings under 6 wk of age, while older birds remain unaffected. The high morbidity and mortality has an economic impact on intensive duck production farming. Duck hepatitis virus Types 2 and 3 are astroviruses in the family of Astroviridae with similarity phylogenetically to turkey astroviruses, implicating the potential for cross-species infections between strains. Duck astrovirus (DAstV) causes
Wool-Lewis, Rouven J.; Bates, Paul
Studies analyzing Ebola virus replication have been severely hampered by the extreme pathogenicity of this virus. To permit analysis of the host range and function of the Ebola virus glycoprotein (Ebo-GP), we have developed a system for pseudotyping these glycoproteins into murine leukemia virus (MLV). This pseudotyped virus, MLV(Ebola), can be readily concentrated to titers which exceed 5 × 106 infectious units/ml and is effectively neutralized by antibodies specific for Ebo-GP. Analysis of ...
Tracy D Reynolds; Buonocore, Linda; Rose, Nina F.; Rose, John K.; Robek, Michael D.
More than 500,000 people die each year from the liver diseases that result from chronic hepatitis B virus (HBV) infection. Therapeutic vaccines, which aim to elicit an immune response capable of controlling the virus, offer a potential new treatment strategy for chronic hepatitis B. Recently, an evolved, high-titer vaccine platform consisting of Semliki Forest virus RNA replicons that express the vesicular stomatitis virus glycoprotein (VSV G) has been described. This platform generates virus...
Norrby, E; Sheshberadaran, H; Rafner, B
Intergenic antigenic relationships between measles virus and respiratory syncytial (RS) virus-specific structural components were studied by using monoclonal antibodies. Of 75 monoclonal antibodies against these components, only one, an anti-measles virus hemagglutinin monoclonal antibody, cross-reacted. Immunofluorescence analysis of measles virus- and RS virus-infected cells with this monoclonal antibody showed qualitatively different staining patterns which indicated that the antigen invol...
Holm, Christian K.; Rahbek, Stine H.; Gad, Hans Henrik; Bak, Rasmus O.; Jakobsen, Martin R; Jiang, Zhaozaho; Hansen, Anne Louise; Jensen, Simon K.; Sun, Chenglong; Thomsen, Martin K.; Laustsen, Anders; Nielsen, Camilla G.; Severinsen, Kasper; Xiong, Yingluo; Burdette, Dara L.
Stimulator of interferon genes (STING) is known be involved in control of DNA viruses but has an unexplored role in control of RNA viruses. During infection with DNA viruses STING is activated downstream of cGAMP synthase (cGAS) to induce type I interferon. Here we identify a STING-dependent, cGAS-independent pathway important for full interferon production and antiviral control of enveloped RNA viruses, including influenza A virus (IAV). Further, IAV interacts with STING through its conserve...
Hughes, Austin L.; Hughes, Mary Ann K.
Analysis of the pattern of nucleotide diversity in 222 independent viral sequence datasets showed the prevalence of purifying selection. In spite of the higher mutation rate of RNA viruses, our analyses revealed stronger evidence of the action of purifying selection in RNA viruses than in DNA viruses. The ratio of nonsynonymous to synonymous nucleotide diversity was significantly lower in RNA viruses than in DNA viruses, indicating that nonsynonymous mutations have been removed at a greater r...
Petrzik, Karel; Koloniuk, Igor
Roč. 40, č. 2 (2010), s. 290-292. ISSN 0920-8569 R&D Projects: GA ČR GA522/07/0053 Institutional research plan: CEZ:AV0Z50510513 Keywords : Capsid proteins * plant virus * Radish mosaic virus * Turnip ringspot virus Subject RIV: EE - Microbiology, Virology Impact factor: 1.693, year: 2010
Viruses rapidly evolve and can emerge in unpredictable ways. Mechanisms by which food-borne viruses may enter human populations and become pathogens is discussed. It is known the majority of viruses emerge from zoonotic animal reservoirs, often by adapting and infecting intermediate hosts, such as ...
Fischer, Robert J.; Judson, Seth; Miazgowicz, Kerri; Bushmaker, Trent; Munster, Vincent J.
On March 20, 2015, a case of Ebola virus disease was identified in Liberia that most likely was transmitted through sexual contact. We assessed the efficiency of detecting Ebola virus in semen samples by molecular diagnostics and the stability of Ebola virus in ex vivo semen under simulated tropical conditions.
Špak, Josef; Kubelková, Darina
Bonn : DPG and BBA, 2002. s. 50. [Joint Conference of the International Working Groups on Legume Viruses and Vegetale Viruses /1./. 04.08.2002-09.08.2002, Bonn] Institutional research plan: CEZ:AV0Z5051902 Keywords : plant pathology * viruses Subject RIV: EE - Microbiology, Virology
Full Text Available The health and vigour of honeybee colonies are threatened by numerous parasites (such as Varroa destructor and Nosema spp. and pathogens, including viruses, bacteria, protozoa. Among honeybee pathogens, viruses are one of the major threats to the health and wellbeing of honeybees and cause serious concern for researchers and beekeepers. To tone down the threats posed by these invasive organisms, a better understanding of bee viral infections will be of crucial importance in developing effective and environmentally benign disease control strategies. Here we summarize recent progress in the understanding of the morphology, genome organization, transmission, epidemiology and pathogenesis of eight honeybee viruses: Deformed wing virus (DWV and Kakugo virus (KV; Sacbrood virus (SBV; Black Queen cell virus (BQCV; Acute bee paralysis virus (ABPV; Kashmir bee virus (KBV; Israeli Acute Paralysis Virus (IAPV; Chronic bee paralysis virus (CBPV. The review has been designed to provide researchers in the field with updated information about honeybee viruses and to serve as a starting point for future research.
Kuzmin, Ivan V; Niezgoda, Michael; Franka, Richard; Agwanda, Bernard; Markotter, Wanda; Beagley, Janet C; Urazova, Olga Y; Breiman, Robert F; Rupprecht, Charles E
During lyssavirus surveillance, 1,221 bats of at least 30 species were collected from 25 locations in Kenya. One isolate of Lagos bat virus (LBV) was obtained from a dead Eidolon helvum fruit bat. The virus was most similar phylogenetically to LBV isolates from Senegal (1985) and from France (imported from Togo or Egypt; 1999), sharing with these viruses 100% nucleoprotein identity and 99.8 to 100% glycoprotein identity. This genome conservancy across space and time suggests that LBV is well adapted to its natural host species and that populations of reservoir hosts in eastern and western Africa have sufficient interactions to share pathogens. High virus concentrations, in addition to being detected in the brain, were detected in the salivary glands and tongue and in an oral swab, suggesting that LBV is transmitted in the saliva. In other extraneural organs, the virus was generally associated with innervations and ganglia. The presence of infectious virus in the reproductive tract and in a vaginal swab implies an alternative opportunity for transmission. The isolate was pathogenic for laboratory mice by the intracerebral and intramuscular routes. Serologic screening demonstrated the presence of LBV-neutralizing antibodies in E. helvum and Rousettus aegyptiacus fruit bats. In different colonies the seroprevalence ranged from 40 to 67% and 29 to 46% for E. helvum and R. aegyptiacus, respectively. Nested reverse transcription-PCR did not reveal the presence of viral RNA in oral swabs of bats in the absence of brain infection. Several large bat roosts were identified in areas of dense human populations, raising public health concerns for the potential of lyssavirus infection. PMID:18305130
Full Text Available IntroductionHepatitis C virus (HCV is an important cause of chronic liver disease. HCV causes 20% of acute hepatitis cases, 70% of all chronic hepatitis cases, 40% of all cases of liver cirrhosis, 60% of hepatocellular carcinomas, and 30% of liver transplants in Europe(1. It is also recognized as the leading cause of liver transplantation in the world(2. Only 20% of infected individuals will recover from this viral infection, while the rest become chronically infected(3. While the majority of chronically infected individuals never exhibit symptoms, approximately 10-30% of these patients will eventually develop cirrhosis or hepatocellular carcinoma, both of which are associated with significant morbidity and mortality(4.More than 170 million people worldwide are chronically infected with HCV. According to WHO report in 2002, chronic liver diseases were responsible for 1.4 million deaths, including 796,000 due to cirrhosis and 616,000 due to primary liver cancer. At least 20% of these deaths are probably attributable to HCV infection- more than 280,000 deaths(5, 6. The prevalence of chronic HCV infection in general population varies greatly in different parts of the world, being estimated between 0.1 and 5%, with a peak prevalence of 20- 25% in Egypt. HCV prevalence seems to be less than 1% in Iran, which is much lower than most of the neighboring countries(7. HCV was the first virus discovered by molecular cloning method without the direct use of biologic or biophysical methods. This was accomplished by extracting, copying into cDNA, and cloning all the nucleic acid from the plasma of a chimpanzee infected with non- A, non-B hepatitis by contaminated factor XIII concentrate(8. The HCV genome is a positive-sense, singlestranded RNA genome approximately 10 kb long. It has marked similarities to those of members of the genera Pestivirus and Flavivirus. Different HCV isolates from around the world show substantial nucleotide sequence variability
Nucleic acids contain various amounts of trace elements. With divalent cations tobacco mosaic virus ribonucleic acid (TMV-RNA) undergoes changes in optical density at 258 mμ in both optical rotation and in sedimentation behaviour. These changes suggested the transformation from a random coil to a more orderly configuration. The connection between trace elements and the biological activity of TMV-RNA has been investigated. However, the relationship between metal ions and the virus infection process has not received much attention. This subject is discussed briefly in this paper. 8 refs
Overview:The aim of the studies described in this thesis was to obtain a thorough understanding of the main factors determining the spread of a potyvirus in a high plant density crop. The factors studied included the relationships between virus, host and vector, the spread of the virus around an initial virus source consisting of one or more infected plants, the spread of the virus by the prevailing aphid population, and the effect of plant density on the spread of the virus. A time-save samp...
Full text: The effects of gamma radiation on foot-and-mouth disease virus in vitro and in situ have been studied. The data so far obtained show that a dose of 2 Mrad is required to inactivate virus in infected animal carcasses. But the dose may adversely affect the organoleptic quality of the meat. Experiments in vitro and in situ are necessary to study the effects of ionizing radiation on other viruses, such as rinderpest, swine fever and African swine fever-viruses, associated with animal products. Radiation may offer a possible means of eliminating the virus titre in many animal products and solve consequent quarantine problems. (author)
Koonin Eugene V; Dolja Valerian V
Abstract In a recent BMC Evolutionary Biology article, Huiquan Liu and colleagues report two new genomes of double-stranded RNA (dsRNA) viruses from fungi and use these as a springboard to perform an extensive phylogenomic analysis of dsRNA viruses. The results support the old scenario of polyphyletic origin of dsRNA viruses from different groups of positive-strand RNA viruses and additionally reveal extensive horizontal gene transfer between diverse viruses consistent with the network-like r...
Graham Barney S
Full Text Available Abstract The interaction between viruses and dendritic cells (DCs is varied and complex. DCs are key elements in the development of a host response to pathogens such as viruses, but viruses have developed survival tactics to either evade or diminish the immune system that functions to kill and eliminate these micro-organisms. In the present review we summarize current concepts regarding the function of DCs in the immune system, our understanding of how viruses alter DC function to attenuate both the virus-specific and global immune response, and how we may be able to exploit DC function to prevent or treat viral infections.
Nirav R. Soni
Full Text Available Zika virus (ZIKV is a member of the virus family Flaviviridae and the genus Flavivirus, transmitted by daytime-active Aedes mosquitoes, such as A. aegypti. ZIKV will continue to spread and it will be difficult to determine how the virus will spread over time. Sign and symptoms of ZIKAVD (Zika virus disease were conjunctivitis (red eyes, back pain, birth defect-abnormal brain development known as microcephaly and it is diagnosed through PCR (polymerase chain reaction and virus isolation from blood samples.
The research was carried out, in the period 2002-2004 in order to determine the presence and distribution of potato viruses at 12 different locations and on 9 different potato varieties grown in Montenegro. The research included collecting of samples in seed potato crops and testing of six economically important potato viruses: Potato leaf roll virus (PLRV), Potato virus Y (PVY), Potato virus X (PVX), Potato virus S (PVS), Potato virus A (PVA) i Potato viru...
Ajiro, Masahiko; Zheng, Zhi-Ming
Approximately 10.8% of human cancers are associated with infection by an oncogenic virus. These viruses include human papillomavirus (HPV), Epstein–Barr virus (EBV), Merkel cell polyomavirus (MCV), human T-cell leukemia virus 1 (HTLV-1), Kaposi's sarcoma-associated herpesvirus (KSHV), hepatitis C virus (HCV) and hepatitis B virus (HBV). These oncogenic viruses, with the exception of HCV, require the host RNA splicing machinery in order to exercise their oncogenic activities, a strategy that a...
Jelena Zindović; Janoš Berenji; Milena Pauković; Ivana Đekić; Aleksandra Bulajić; Branka Krstić
Five viruses: Potato Virus Y (PVY), Tomato Spotted Wilt Virus, Cucumber Mosaic Virus, Tobacco Mosaic Virus and Alfalfa Mosaic Virus, of which PVY was predominant, were detected by serological testing of tobacco samples collected from many localities in Vojvodina in 2006. Viruses are the most important pathogens in tobacco and PVY causes considerable economic damages all over the world. A PVY population comprises several different strain groups, strain subgroups and recombinant strains. Among ...
Wallis, C; Melnick, J L; Rao, V C; Sox, T E
A simple method with poliovirus as the model was developed for recovering human enteric viruses from aerosols. Filterite filters (pore size, 0.45 micron; Filterite Corp., Timonium, Md.) moistened with glycine buffer (pH 3.5) were used for adsorbing the aerosolized virus. No virus passed the filter, even with air flow rates of 100 liters/min. Virus recovery from the filter was achieved by rapid elution with 800 ml of glycine buffer, pH 10. The virus in the primary eluate was reconcentrated by adjusting the pH to 3.5, adding AlCl3 to 0.0005 M, collecting the virus on a 0.25-micron-pore Filerite disk (diameter, 25 mm) and and eluting with 6 ml of buffer, pH 10. With this method, virus could be detected regularly in aerosols produced by flushing when 3 X 10(8) PFU of poliovirus were present in the toilet bowl. Poliovirus-containing fecal material from two of four infants who had recently received oral polio vaccine also yielded virus in the aerosols when feces containing 2.4 X 10(7) to 4.5 X 10(7) PFU of virus had been added to the toilet bowl. Persons infected with a variety of natural enteric viruses are known to excrete this amount of virus in their daily stools. PMID:3004329
The sensitiveness of viruses to gamma rays was compared using eight viruses suspended with low concentration in drinking water, and four viruses present in high concentrations in tissue culture medium. The results show that the following factors are responsible for the resistance of viruses to gamma rays: 1. type of virus: the specific radiation resistance varied considerably; in general, there was a closer correlation with the general resistance of the virus to chemico-physical influences than with the type of nucleic acid of the virus examined; 2. medium of suspension and state of aggregation: high protein content and lyophilisation increased the resistance to gamma rays widely; 3. virus concentration: the virus reduction by a factor of 10 in suspensions with high virus concentration needed a higher radiation dose compared with suspensions of low virus content. All the results demonstrate the kinetics of inactivation to be a 1st order reaction. The increase of temperature to 410C did not show any significant influence. (orig.)
Choi, Hoseong; Jo, Yeonhwa; Lian, Sen; Jo, Kyoung-Min; Chu, Hyosub; Yoon, Ju-Yeon; Choi, Seung-Kook; Kim, Kook-Hyung; Cho, Won Kyong
The chrysanthemum is one of popular flowers in the world and a host for several viruses. So far, molecular interaction studies between the chrysanthemum and viruses are limited. In this study, we carried out a transcriptome analysis of chrysanthemum in response to three different viruses including Cucumber mosaic virus (CMV), Tomato spotted wilt virus (TSWV) and Potato virus X (PVX). A chrysanthemum 135K microarray derived from expressed sequence tags was successfully applied for the expression profiles of the chrysanthemum at early stage of virus infection. Finally, we identified a total of 125, 70 and 124 differentially expressed genes (DEGs) for CMV, TSWV and PVX, respectively. Many DEGs were virus specific; however, 33 DEGs were commonly regulated by three viruses. Gene ontology (GO) enrichment analysis identified a total of 132 GO terms, and of them, six GO terms related stress response and MCM complex were commonly identified for three viruses. Several genes functioning in stress response such as chitin response and ethylene mediated signaling pathway were up-regulated indicating their involvement in establishment of host immune system. In particular, TSWV infection significantly down-regulated genes related to DNA metabolic process including DNA replication, chromatin organization, histone modification and cytokinesis, and they are mostly targeted to nucleosome and MCM complex. Taken together, our comparative transcriptome analysis revealed several genes related to hormone mediated viral stress response and DNA modification. The identified chrysanthemums genes could be good candidates for further functional study associated with resistant to various plant viruses. PMID:25904110
M Khanna; P Kumar; K Choudhary; B Kumar; V K Vijayan
Since 1918, influenza virus has been one of the major causes of morbidity and mortality, especially among young children. Though the commonly circulating strain of the virus is not virulent enough to cause mortality, the ability of the virus genome to mutate at a very high rate may lead to the emergence of a highly virulent strain that may become the cause of the next pandemic. Apart from the influenza virus strain circulating in humans (H1N1 and H3N2), the avian influenza H5N1 H7 and H9 virus strains have also been reported to have caused human infections, H5N1 H7 and H9 have shown their ability to cross the species barrier from birds to humans and further replicate in humans. This review addresses the biological and epidemiological aspects of influenza virus and efforts to have a control on the virus globally.
Koonin Eugene V
Full Text Available Abstract In a recent BMC Evolutionary Biology article, Huiquan Liu and colleagues report two new genomes of double-stranded RNA (dsRNA viruses from fungi and use these as a springboard to perform an extensive phylogenomic analysis of dsRNA viruses. The results support the old scenario of polyphyletic origin of dsRNA viruses from different groups of positive-strand RNA viruses and additionally reveal extensive horizontal gene transfer between diverse viruses consistent with the network-like rather than tree-like mode of viral evolution. Together with the unexpected discoveries of the first putative archaeal RNA virus and a RNA-DNA virus hybrid, this work shows that RNA viral genomics has major surprises to deliver. See research article: http://www.biomedcentral.com/1471-2148/12/91
KOU Zheng; LEI FuMin; WANG ShengYue; ZHOU YanHong; LI TianXian
Avian influenza A viruses could get across the species barrier and be fatal to humans. Highly patho-genic avian influenza H5N1 virus was an example. The mechanism of interspecies transmission is not clear as yet. In this research, the protein sequences of 237 influenza A viruses with different subtypes were transformed into pseudo-signals. The energy features were extracted by the method of wavelet packet decomposition and used for virus classification by the method of hierarchical clustering. The clustering results showed that five patterns existed in avian influenza A viruses, which associated with the phenotype of interspecies transmission, and that avian viruses with patterns C and E could across species barrier and those with patterns A, B and D might not have the abilities. The results could be used to construct an early warning system to predict the transmissibility of avian influenza A viruses to humans.
Full Text Available Avian influenza outbreaks in poultry have been reported in Java island since August 2003. A total of 14 isolates of avian influenza virus has been isolated from October 2003 to October 2004. The viruses have been identified as HPAI H5N1 subtype. All of them were characterized further at genetic level and also for their pathogenicity. Phylogenetic analysis showed all of the avian influenza virus isolates were closely related to avian influenza virus from China (A/Duck/China/E319-2/03(H5N1. Molecular basis of pathogenicity in HA cleavage site indicated that the isolates of avian influenza virus have multiple basic amino acid (B-X-B-R indicating that all of the isolates representing virulent avian influenza virus (highly pathogenic avian influenza virus.
Bloch, Evan M.
Zika virus is a mosquitoborne flavivirus that is the focus of an ongoing pandemic and public health emergency. Previously limited to sporadic cases in Africa and Asia, the emergence of Zika virus in Brazil in 2015 heralded rapid spread throughout the Americas. Although most Zika virus infections are characterized by subclinical or mild influenza-like illness, severe manifestations have been described, including Guillain-Barre syndrome in adults and microcephaly in babies born to infected mothers. Neither an effective treatment nor a vaccine is available for Zika virus; therefore, the public health response primarily focuses on preventing infection, particularly in pregnant women. Despite growing knowledge about this virus, questions remain regarding the virus’s vectors and reservoirs, pathogenesis, genetic diversity, and potential synergistic effects of co-infection with other circulating viruses. These questions highlight the need for research to optimize surveillance, patient management, and public health intervention in the current Zika virus epidemic. PMID:27070380
Špak, Josef; Fránová, Jana
Jokioinen : MTT Agrifood Research, 2008. s. 68. [COST863, WG2 and WG3 Joint SGM "Plant Health in Changing Environment . 19.05.2008-20.05.2008, Jokioinen] Institutional research plan: CEZ:AV0Z50510513 Keywords : plant disease * viruses * strawberry Subject RIV: EE - Microbiology, Virology
Full Text Available Oncolytic virotherapy has shown impressive results in preclinical studies and first promising therapeutic outcomes in clinical trials as well. Since viruses are known for a long time as excellent vaccination agents, oncolytic viruses are now designed as novel anticancer agents combining the aspect of lysis-dependent cytoreductive activity with concomitant induction of antitumoral immune responses. Antitumoral immune activation by oncolytic virus infection of tumor tissue comprises both, immediate effects of innate immunity and also adaptive responses for long lasting antitumoral activity which is regarded as the most prominent challenge in clinical oncology. To date, the complex effects of a viral tumor infection on the tumor microenvironment and the consequences for the tumor-infiltrating immune cell compartment are poorly understood. However, there is more and more evidence that a tumor infection by an oncolytic virus opens up a number of options for further immunomodulating interventions such as systemic chemotherapy, generic immunostimulating strategies, dendritic cell-based vaccines, and antigenic libraries to further support clinical efficacy of oncolytic virotherapy.
Reginald Tucker reads an abridged version of the EID perspective Bat Flight and Zoonotic Viruses. Created: 5/30/2014 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID). Date Released: 6/2/2014.
Reginald Tucker reads an abridged version of the commentary by CDC author Ronald Rosenberg, Threat from Emerging Vectorborne Viruses. Created: 6/9/2016 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID). Date Released: 6/9/2016.
K. Weijer (Kees); F.G.C.M. Uytdehaag (Fons); A.D.M.E. Osterhaus (Ab)
textabstractFeline leukaemia virus (FeLV) usually occurs in its natural species, the domestic cat. FeLV is also important to human individuals as a comparative model, as it may cause a variety of diseases, some malignant and some benign, such as immunosuppression, which bears a resemblance to AIDS (
Leruste, Amandine; Bouvier, Thierry; Bettarel, Yvan
The distribution of viruses inhabiting the coral mucus remains undetermined, as there is no suitable standardized procedure for their separation from this organic matrix, principally owing to its viscosity and autofluorescence. Seven protocols were tested, and the most efficient separations were obtained from a chemical treatment requiring potassium citrate.
Leruste, Amandine; Bouvier, Thierry; Bettarel, Yvan
The distribution of viruses inhabiting the coral mucus remains undetermined, as there is no suitable standardized procedure for their separation from this organic matrix, principally owing to its viscosity and autofluorescence. Seven protocols were tested, and the most efficient separations were obtained from a chemical treatment requiring potassium citrate. PMID:22729548
Louis H. Nel
Full Text Available The Duvenhage virus (DUVV constitutes one of the 11 species in the Lyssavirus genus and causes fatal rabies encephalitis. The virus is associated with insectivorous bat species and three human cases have been reported, all of which were linked to contact with bats. Few of these isolates have been studied and thus little is known about the phylogeny and epidemiology of this lyssavirus. Until 2007, when an isolate was made from the East African country of Kenya, all isolations of this virus had been from southern Africa. This discovery led to many questions regarding the spread and diversity of this lyssavirus. Phylogenetic analysis indicated that the DUVV isolates constitute two different lineages, in which the southern African isolates group together to form one lineage and the more recent isolate from Kenya constitutes a new, second lineage. We found that the new isolate has a genetic variation that has not yet been seen for DUVV. Not only is our lack of knowledge regarding the geographical distribution of this uniquely African virus emphasised, but we have also demonstrated the potential diversity within this genotype.
Izri, Arezki; Temmam, Sarah; Moureau, Grégory; Hamrioui, Boussad; de Lamballerie, Xavier; Charrel, Rémi N.
To determine whether sandfly fever Sicilian virus (SFSV) is present in Algeria, we tested sandflies for phlebovirus RNA. A sequence closely related to that of SFSV was detected in a Phlebotomus ariasi sandfly. Of 60 human serum samples, 3 contained immunoglobulin G against SFSV. These data suggest SFSV is present in Algeria.
Azevedo, Raimunda S. S.; Silva, Eliana V. P.; Carvalho, Valéria L.; Rodrigues, Sueli G.; Neto, Joaquim P. Nunes; Monteiro, Hamilton A. de O.; Peixoto, Victor S.; Chiang, Jannifer O.; Nunes, Márcio R. T.; Vasconcelos, Pedro F.C.
In February 2008, a Mayaro fever virus (MAYV) outbreak occurred in a settlement in Santa Barbara municipality, northern Brazil. Patients had rash, fever, and severe arthralgia lasting up to 7 days. Immunoglobulin M against MAYV was detected by ELISA in 36 persons; 3 MAYV isolates sequenced were characterized as genotype D.
In this thesis the isolation and characterization of a number of mutants of alfalfa mosaic virus, a plant virus with a coat protein dependent genome, is described. Thermo-sensitive (ts) mutants were selected since, at least theoretically, ts mutations can be present in all virus coded functions. It was found that a high percentage of spontaneous mutants, isolated because of their aberrant symptoms, were ts. The majority of these isolates could grow at the non-permissive temperature in the presence of a single wild type (wt) component. To increase the mutation rate virus preparations were treated with several mutagens. After nitrous acid treatment or irradiation with ultraviolet light, an increase in the level of mutations was observed. UV irradiation was preferred since it did not require large amounts of purified viral components. During the preliminary characterization of potential ts mutants the author also obtained one structural and several symptom mutants which were analysed further (chapter 7, 8 and 9). The properties of the ts mutants are described in chapter 3-7. (Auth.)
J Gordon Millichap
Full Text Available Epidemiological features of West Nile Virus (WNV disease among children (<18 years of age reported to the Centers for Disease Control and Prevention from 1999 through 2007 were analyzed and compared with those of adult WNV neuroinvasive disease (WNND, in a study at CDC&P, Fort Collins, CO.
Dr. Adam MacNeil, an epidemiologist at CDC, discusses Ebola virus. Created: 10/1/2012 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID); National Center for Immunization and Respiratory Diseases (NCIRD). Date Released: 10/1/2012.
Cases of microcephaly brought about by the Zika virus have brought professional and personal challenges for nurses in Brazil. Paediatric nurses, such as Roberta Seabra (pictured), take over as part of the multidisciplinary team once the baby is born. In this article health writer Jacqui Thornton presents some personal stories. PMID:27615590
Psoralen compounds covalently bind to nucleic acids when irradiated with long-wavelength ultraviolet light. This treatment can destroy the infectivity of deoxyribonucleic acid and ribonucleic acid viruses. Two psoralen compounds, 4'-hydroxymethyltrioxsalen and 4'-aminomethyltrioxsalen, were used with long-wavelength ultraviolet light to inactivate cell-free herpes simplex and influenza viruses and to render virus-infected cells noninfectious. This method of inactivation was compared with germicidal (short-wavelength) ultraviolet light irradiation. The antigenicity of the treated, virus-infected, antigen-bearing cells was examined by immunofluorescence and radioimmunoassay and by measuring the capacity of the herpes simplex virus-infected cells to stimulate virus-specific lymphocyte proliferation. The infectivity of the virus-infected cells could be totally eliminated without altering their viral antigenicity. The use of psoralen plus long-wavelength ultraviolet light is well suited to the preparation of noninfectious virus antigens and virus antigen-bearing cells for immunological assays
Stanković, I; Bulajić, A; Vučurović, A; Ristić, D; Milojević, K; Berenji, J; Krstić, B
In a four-year survey to determine the presence and distribution of viruses in tobacco crops at 17 localities of the Vojvodina Province and Central Serbia, 380 samples were collected and analyzed by DAS-ELISA. Out of the seven viruses tested, tomato spotted wilt virus (TSWV), potato virus Y (PVY), tobacco mosaic virus (TMV), cucumber mosaic virus (CMV), and alfalfa mosaic virus (AMV) were detected in 37.9, 33.4, 28.7, 23.9, and 15.5% of the total tested samples, respectively. TSWV was the most frequently found virus at the localities of Central Serbia, while PVY and CMV were the most frequent viruses in the Vojvodina Province. Single infections were prevalent in years 2005-2007 and the most frequent were those of PVY. A triple combination of those viruses was most frequent mixed infection type in 2008. The presence of all five detected viruses was confirmed in selected ELISA-positive samples by RT-PCR and sequencing. The comparisons of obtained virus isolate sequences with those available in NCBI, confirmed the authenticity of serologically detected viruses. Phylogenetic analysis based on partial nucleocapsid gene sequences revealed a joint clustering of Serbian, Bulgarian and Montenegrin TSWV isolates into one geographic subpopulation, which was distinct from the other subpopulation of TSWV isolates from the rest of the European countries. The high incidence of viruses in Serbian tobacco crops highlights the importance of enhancing farmers knowledge towards better implementation of control strategies for preventing serious losses. PMID:22149499
The major features that distinguish recurrent herpes simplex virus infections from zoster are illustrated in this article by two case histories. The clinical and epidemiologic features that characterize recurrent herpes simplex virus and varicella-zoster virus infections are reviewed. It is noted that herpesvirus infections are more common and severe in patients with cellular immune deficiency. Each virus evokes both humoral and cellular immune response in the course of primary infection. DNA hybridization studies with RNA probes labelled with sulfur-35 indicate that herpes simplex viruses persist within neurons, and that varicella-zoster virus is found in the satellite cells that encircle the neurons
Belser, Jessica A; Blixt, Ola; Chen, Li-Mei; Pappas, Claudia; Maines, Taronna R; Van Hoeven, Neal; Donis, Ruben; Busch, Julia; McBride, Ryan; Paulson, James C; Katz, Jacqueline M; Tumpey, Terrence M
viruses from The Netherlands in 2003 maintained the classic avian-binding preference for alpha2-3-linked sialic acids (SA) and are not readily transmissible in ferrets, as observed previously for highly pathogenic H5N1 viruses. However, H7N3 viruses isolated from Canada in 2004 and H7N2 viruses from the...... in the upper respiratory tract of ferrets and was capable of transmission in this species by direct contact. These results indicate that H7 influenza viruses from the North American lineage have acquired sialic acid-binding properties that more closely resemble those of human influenza viruses and...
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Herpes simplex virus serological assays. 866.3305... simplex virus serological assays. (a) Identification. Herpes simplex virus serological assays are devices... herpes simplex virus in serum. Additionally, some of the assays consist of herpes simplex virus...
A new, symptomless virus was identified in blueberry. The dsRNA genome of the virus, provisionally named Blueberry latent virus (BBLV), codes for two putative proteins and lacks a movement protein, a property only shared with cryptic viruses. More than 35 isolates of the virus from different cultiv...
... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Wart Vaccine, Killed Virus. 113.206... AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.206 Wart Vaccine, Killed Virus. Wart Vaccine, Killed Virus, shall be...
... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Bovine Virus Diarrhea Vaccine. 113.311... Virus Vaccines § 113.311 Bovine Virus Diarrhea Vaccine. Bovine Virus Diarrhea Vaccine shall be prepared... virus diarrhea susceptible calves shall be used as test animals (20 vaccinates and five controls)....
Li, Jiandong; Li, Dexin
Zika virus disease is an emerging mosquito-borne acute infectious disease caused by Zika virus, so far there have been no available vaccine or specific treatment. Currently, the outbreaks of Zika virus disease mainly occurs in the Americas, but the regional distribution of the disease is in rapid expansion, 34 countries and territories have reported autochthonous transmission of the virus. The illness is usually mild with very rarely death, but increased reports of birth defects and neurologic disorders in the areas affected by Zika virus has caused extensive concern worldwide. In China, the competent vectors for Zika virus are widely distributed, imported viraemic cases may become a source of local transmission of the virus. However, Zika virus disease is preventable, the spread of virus could be stopped when the effective prevention measures are taken. This paper summarizes the retrieval results from Medline database and the information from the reports of the governments of countries affected or health organizations about the epidemiological characteristics of Zika virus disease. PMID:27005530
Esfandiari, N; Kohi-Habibi, M; Mosahebi, Gh
A survey was conducted to determine the incidence of Alfalfa mosaic virus (AMV), Bean yellow mosaic virus (BYMV), Broad bean wilt virus-1 (BBWV), Pea leafroll virus (PLRV), Pea enation mosaic virus (PEMV), Pea seed borne mosaic virus (PSbMV), Potato virus x(PVX), Tomato mosaic virus (ToMV), Tomato spotted wilt virus (TSWV) on pea (Pisum sativum) in Iran. A Total of 1276 random and 684 symptomatic pea samples were collected during the spring and summer of 2002-2004 in Tehran province of Iran, where pea is grown, and tested by enzyme-linked immunosorbent assay (ELISA) using specific polyclonal antibodies. Serological diagnoses were confirmed by electron microscopy and host range studies. Incidence of viruses in decreasing order was PVX (69%), ToMV (59%), PSbMV (36.6%), BBWV-1 (26.1%), BYMV (20.3%), AMV (17.77%), TSWV (12.6%), PEMV (10.9%), PLRV (6.78%). In this survey, natural occurrence of AMV, BBWV-1, PSbMV, TSWV, PVX and ToMV was reported for the first time on the pea in Iran. PMID:17390891
Currently, little is known about the ankyrin/F-box protein B4. Here, we report that B4R-null viruses exhibited reduced plaque size in tissue culture, and decreased ability to spread, as assessed by multiple-step growth analysis. Electron microscopy indicated that B4R-null viruses still formed mature and extracellular virions; however, there was a slight decrease of virions released into the media following deletion of B4R. Deletion of B4R did not affect the ability of the virus to rearrange actin; however, VACV811, a large vaccinia virus deletion mutant missing 55 open reading frames, had decreased ability to produce actin tails. Using ectromelia virus, a natural mouse pathogen, we demonstrated that virus devoid of EVM154, the B4R homolog, showed decreased spread to organs and was attenuated during infection. This initial characterization suggests that B4 may play a role in virus spread, and that other unidentified mediators of actin tail formation may exist in vaccinia virus. - Highlights: • B4R-null viruses show reduced plaque size, and decreased ability to spread. • B4R-null viruses formed mature and extracellular virions; and rearranged actin. • Virus devoid of EVM154, the B4R homolog, was attenuated during infection. • Initial characterization suggests that B4 may play a role in virus spread. • Unidentified mediators of actin tail formation may exist in vaccinia virus
Flores, Sonia C.; Almodovar, Sharilyn
The following state-of-the-art seminar was delivered as part of the Aspen Lung Conference on Pulmonary Hypertension and Vascular Diseases held in Aspen, Colorado in June 2012. This paper will summarize the lecture and present results from a nonhuman primate model of infection with Simian (Human) Immunodeficiency Virus - nef chimeric virions as well as the idea that polymorphisms in the HIV-1 nef gene may be driving the immune response that results in exuberant inflammation and aberrant endoth...
Kate R. Searle; Barber, James; Stubbins, Francesca; Labuschagne, Karien; Carpenter, Simon; Butler, Adam; Denison, Eric; Sanders, Christopher; Mellor, Philip S.; Wilson, Anthony; Nelson, Noel; Gubbins, Simon; Purse, Bethan V.
Since 2006, arboviruses transmitted by Culicoides biting midges (Diptera: Ceratopogonidae) have caused significant disruption to ruminant production in northern Europe. The most serious incursions involved strains of bluetongue virus (BTV), which cause bluetongue (BT) disease. To control spread of BTV, movement of susceptible livestock is restricted with economic and animal welfare impacts. The timing of BTV transmission in temperate regions is partly determined by the seasonal presence of ad...
Kate R. Searle; Barber, James; Stubbins, Francesca; Labuschagne, Karien; Carpenter, Simon; Butler, Adam; Denison, Eric; Sanders, Christopher; Mellor, Philip S.; Wilson, Anthony; Nelson, Noel; Gubbins, Simon; Purse, Bethan V.
Since 2006, arboviruses transmitted by Culicoides biting midges (Diptera: Ceratopogonidae) have caused significant disruption to ruminant production in northern Europe. The most serious incursions involved strains of bluetongue virus (BTV), which cause bluetongue (BT) disease. To control spread of BTV, movement of susceptible livestock is restricted with economic and animal welfare impacts. The timing of BTV transmission in temperate regions is partly determined by the seasonal presence of ad...
Silvia Caprari; Saskia Metzler; Thomas Lengauer; Olga V Kalinina
The origin and evolution of viruses is a subject of ongoing debate. In this study, we provide a full account of the evolutionary relationships between proteins of significant sequence and structural similarity found in viruses that belong to different classes according to the Baltimore classification. We show that such proteins can be found in viruses from all Baltimore classes. For protein families that include these proteins, we observe two patterns of the taxonomic spread. In the first pat...
Infection of nontransformed mouse cells with uv-irradiated herpes simplex virus (uv-HSV) resulted in the activation of an endogenous xenotropic (x-tropic) type C virus. Synthesis of type C virus persisted for only a few days, with most of the virus remaining cell associated. The levels of type C virus activated by uv-HSV varied depending on the multiplicity of infection (m.o.i.) and the uv dose. At low uv doses, where cell killing occurred, little or no type C virus synthesis was observed. Maximum levels of type C virus synthesis were observed with the minimum uv dose which eliminated cell killing by HSV. Synthesis of type C virus, albeit at lower levels, was still observed at uv doses beyond those required to prevent cell killing
Sun, Mei; Li, Dandan; Han, Dun; Jia, Changsheng
The impact of anti-virus software on the spreading of computer virus is investigated via developing a mathematical model in this paper. Considering the anti-virus software may not be effective, as it may be an outdated version, and then the computers may be infected with a reduced incidence rate. According to the method of next generation matrix, the basic reproduction number is derived. By introducing appropriate Lyapunov function and the Routh stability criterion, acquiring the stability conditions of the virus-free equilibrium and virus equilibrium. The effect of anti-virus software and disconnecting rate on the spreading of virus are also analyzed. When combined with the numerical results, a set of suggestions are put forward for eradicating virus effectively.
Simões E Silva, Ana Cristina; Moreira, Janaina Matos; Romanelli, Roberta Maia Castro; Teixeira, Antonio Lucio
Before 2007, Zika virus (ZIKV) was generally considered as an arbovirus of low clinical relevance, causing a mild self-limiting febrile illness in tropical Africa and Southeast Asia. Currently, a large, ongoing outbreak of ZIKV that started in Brazil in 2015 is spreading across the Americas. Virus infection during pregnancy has been potentially linked to congenital malformations, including microcephaly. In addition to congenital malformations, a temporal association between ZIKV infection and an increase in cases of Guillain-Barré syndrome is currently being observed in several countries. The mechanisms underlying these neurological complications are still unknown. Emerging evidence, mainly from in vitro studies, suggests that ZIKV may have direct effects on neuronal cells. The aim of this study was to critically review the literature available regarding the neurobiology of ZIKV and its potential neuropsychiatric manifestations. PMID:27478378
Full Text Available Since its discovery in 1960 as a contaminant of poliovaccines, Simian Virus 40 (SV40 has been the object of extensive studies to assess whether this oncogenic virus plays a role in human carcinogenesis. Over the last two decades, this question has met with broad scepticism. However, there is increasing evidence linking SV40 to specific types of human cancer, especially malignant mesothelioma. Recently, two laboratories using different experimental approaches independently confirmed that SV40 acts synergistically with environmental fibers to promote mesothelial cell transformation and mesothelioma. Most of the scepticism concerning SV40 and cancer was due to the lack of clear epidemiologic data. However, it is still not clear how SV40 circulates in the human population, making the identification of SV40-exposed versus non-exposed cohorts problematic. Consequently, the most helpful insights into SV40-mediated carcinogenesis have come from molecular pathology, cell and molecular biology, and from animal studies.
Simões e Silva, Ana Cristina; Moreira, Janaina Matos; Romanelli, Roberta Maia Castro; Teixeira, Antonio Lucio
Before 2007, Zika virus (ZIKV) was generally considered as an arbovirus of low clinical relevance, causing a mild self-limiting febrile illness in tropical Africa and Southeast Asia. Currently, a large, ongoing outbreak of ZIKV that started in Brazil in 2015 is spreading across the Americas. Virus infection during pregnancy has been potentially linked to congenital malformations, including microcephaly. In addition to congenital malformations, a temporal association between ZIKV infection and an increase in cases of Guillain–Barré syndrome is currently being observed in several countries. The mechanisms underlying these neurological complications are still unknown. Emerging evidence, mainly from in vitro studies, suggests that ZIKV may have direct effects on neuronal cells. The aim of this study was to critically review the literature available regarding the neurobiology of ZIKV and its potential neuropsychiatric manifestations. PMID:27478378
Alain Alonso Remedios
Full Text Available Ebola virus belongs to the family Filoviridae and causes a highly lethal hemorrhagic fever. Affected patients show an impaired immune response as a result of the evasion mechanisms employed by the virus. Cathepsin is an enzyme present in the granules of phagocytes which cleaves viral surface glycoproteins, allowing virus entry into the host cell. In addition, this virus is resistant to the antiviral effects of type I interferon, promotes the synthesis of proinflammatory cytokines and induces apoptosis of monocytes and lymphocytes. It also induces an incomplete activation of dendritic cells, thus avoiding the presentation of viral antigens. Although specific antibodies are produced after the first week, their neutralizing capacity is doubtful. The virus evades the immune response and replicates uncontrollably in the host. This paper aims to summarize the main characteristics of the immune response to Ebola virus infection.
Fensterl, Volker; Chattopadhyay, Saurabh; Sen, Ganes C
The interferon system protects mammals against virus infections. There are several types of interferons, which are characterized by their ability to inhibit virus replication and resultant pathogenesis by triggering both innate and cell-mediated immune responses. Virus infection is sensed by a variety of cellular pattern-recognition receptors and triggers the synthesis of interferons, which are secreted by the infected cells. In uninfected cells, cell surface receptors recognize the secreted interferons and activate intracellular signaling pathways that induce the expression of interferon-stimulated genes; the proteins encoded by these genes inhibit different stages of virus replication. To avoid extinction, almost all viruses have evolved mechanisms to defend themselves against the interferon system. Consequently, a dynamic equilibrium of survival is established between the virus and its host, an equilibrium that can be shifted to the host's favor by the use of exogenous interferon as a therapeutic antiviral agent. PMID:26958928
European Food Safety Authority
This scientific report provides an overview of all research carried out on Schmallenberg virus (SBV), reviewing the current knowledge on SBV regarding genotyping findings, susceptible species, pathogenesis, transmission routes, immunity, seroprevalence, geographical and temporal SBV spread, improved within-herd transmission model, SBV impact assessment and within-herd and regional spread models. Metagenomic analysis identified SBV as a novel orthobunyavirus emerged in 2011 and it has been det...
Spanish investigators described recently the so-called occult hepatitis C virus (HCV) infection, emphasizing the detection of genomic and antigenomic HCV RNA strands in liver and peripheral blood mononuclear cells. Therefore, the persistence of viral replication in occult HCV infection should be considered as a putative source of infection among family members and patients undergoing invasive procedures, transfusion or transplantation. Additionally, the most worrisome finding is that an occult HCV infection may persist in patients with sustained virological response.
Brno : ÚBO AV ČR, 2006 - (Procházka, P.; Sedláček, J.). s. 22-24 ISBN 80-903329-5-1. [Workshop of the Southeastern European Bird Migration Network (SEEN) /8./. 02.02.2006-05.02.2006, Praha] Institutional research plan: CEZ:AV0Z60930519 Keywords : migratory birds * influenza virus Subject RIV: EG - Zoology
Kilgore, Paul E; Grabenstein, John D; Salim, Abdulbaset M; Rybak, Michael
In March 2014, the largest Ebola outbreak in history exploded across West Africa. As of November 14, 2014, the World Health Organization has reported a total of 21,296 Ebola virus disease (EVD) cases, including 13,427 laboratory-confirmed EVD cases reported from the three most affected countries (Guinea, Liberia, and Sierra Leone). As the outbreak of EVD has spread, clinical disease severity and national EVD case-fatality rates have remained high (21.2-60.8%). Prior to 2013, several EVD outbreaks were controlled by using routine public health interventions; however, the widespread nature of the current EVD outbreak as well as cultural practices in the affected countries have challenged even the most active case identification efforts. In addition, although treatment centers provide supportive care, no effective therapeutic agents are available for EVD-endemic countries. The ongoing EVD outbreak has stimulated investigation of several different therapeutic strategies that target specific viral structures and mechanisms of Ebola viruses. Six to eight putative pharmacotherapies or immunologically based treatments have demonstrated promising results in animal studies. In addition, agents composed of small interfering RNAs targeting specific proteins of Ebola viruses, traditional hyperimmune globulin isolated from Ebola animal models, monoclonal antibodies, and morpholino oligomers (small molecules used to block viral gene expression). A number of EVD therapeutic agents are now entering accelerated human trials in EVD-endemic countries. The goal of therapeutic agent development includes postexposure prevention and EVD cure. As knowledge of Ebola virus virology and pathogenesis grows, it is likely that new therapeutic tools will be developed. Deployment of novel Ebola therapies will require unprecedented cooperation as well as investment to ensure that therapeutic tools become available to populations at greatest risk for EVD and its complications. In this article, we
Glenn Wendy K; Heads Joy; Lawson James S; Whitaker Noel J
Abstract Background There is seemingly consistent and compelling evidence that there is no association between breastfeeding and breast cancer. An assumption follows that milk borne viruses cannot be associated with human breast cancer. We challenge this evidence because past breastfeeding studies did not determine "exposure" of newborn infants to colostrum and breast milk. Methods We conducted a prospective review of 100 consecutive births of infants in the same centre to determine the propo...
Afonso, C. L.; Tulman, E. R.; Lu, Z.; Zsak, L.; Osorio, F. A.; Balinsky, C.; Kutish, G. F.; Rock, D. L.
Swinepox virus (SWPV), the sole member of the Suipoxvirus genus of the Poxviridae, is the etiologic agent of a worldwide disease specific for swine. Here we report the genomic sequence of SWPV. The 146-kbp SWPV genome consists of a central coding region bounded by identical 3.7-kbp inverted terminal repeats and contains 150 putative genes. Comparison of SWPV with chordopoxviruses reveals 146 conserved genes encoding proteins involved in basic replicative functions, viral virulence, host range...
Ou, Shan-Chia; Giambrone, Joseph J.
Infectious laryngotracheitis (ILT) is an important respiratory disease of chickens and annually causes significant economic losses in the poultry industry world-wide. ILT virus (ILTV) belongs to alphaherpesvirinae and the Gallid herpesvirus 1 species. The transmission of ILTV is via respiratory and ocular routes. Clinical and post-mortem signs of ILT can be separated into two forms according to its virulence. The characteristic of the severe form is bloody mucus in the trachea with high morta...
Liu, Shelan; Sha, Jianping; Yu, Zhao; Hu, Yan; Chan, Ta-Chien; Wang, Xiaoxiao; Pan, Hao; Cheng, Wei; Mao, Shenghua; Zhang, Run Ju; Chen, Enfu
The unprecedented epizootic of avian influenza viruses, such as H5N1, H5N6, H7N1 and H10N8, has continued to cause disease in humans in recent years. In 2013, another novel influenza A (H7N9) virus emerged in China, and 30% of those patients died. Pregnant women are particularly susceptible to avian influenza and are more likely to develop severe complications and to die, especially when infection occurs in the middle and late trimesters. Viremia is believed to occur infrequently, and thus vertical transmission induced by avian influenza appears to be rare. However, avian influenza increases the risk of adverse pregnancy outcomes, including spontaneous abortion, preterm birth and fatal distress. This review summarises 39 cases of pregnant women and their fetuses from different countries dating back to 1997, including 11, 15 and 13 infections with H7N9, H5N1 and the 2009 pandemic influenza (H1N1), respectively. We analysed the epidemic features, following the geographical, population and pregnancy trimester distributions; underlying diseases; exposure history; medical timelines; human-to-human transmission; pathogenicity and vertical transmission; antivirus treatments; maternal severity and mortality and pregnancy outcome. The common experiences reported in different countries and areas suggest that early identification and treatment are imperative. In the future, vigilant virologic and epidemiologic surveillance systems should be developed to monitor avian influenza viruses during pregnancy. Furthermore, extensive study on the immune mechanisms should be conducted, as this will guide safe, rational immunomodulatory treatment among this high-risk population. Most importantly, we should develop a universal avian influenza virus vaccine to prevent outbreaks of the different subtypes. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27187752
Wang, Zhaoyang; Wang, Peigang; An, Jing
An emerging mosquito-borne arbovirus named Zika virus (ZIKV), of the family Flaviviridae and genus Flavivirus, is becoming a global health threat. ZIKV infection was long neglected due to its sporadic nature and mild symptoms. However, recently, with its rapid spread from Asia to the Americas, affecting more than 30 countries, accumulating evidences have demonstrated a close association between infant microcephaly and Zika infection in pregnant women. Here, we reviewed the virological, epidemiological, and clinical essentials of ZIKV infection. PMID:27129450
Marion, P L; Oshiro, L S; Regnery, D C; Scullard, G H; Robinson, W S
A virus given the name ground squirrel hepatitis virus (or GSHV), with many of the unique characteristics of human hepatitis B virus (HBV), has been found in Beechey ground squirrels in northern California. Common features include virus morphology, viral DNA size and structure, a virion DNA polymerase that repairs a single-stranded region in the viral DNA, crossreacting viral antigens, and persistent infection with viral antigen continuously in the blood. Although similar, GSHV and HBV Are no...
Heike Nowag; Bruno Guhl; Kerstin Thriene; Susana Romao; Urs Ziegler; Joern Dengjel; Christian Münz
Epstein Barr virus (EBV) persists as a latent herpes virus infection in the majority of the adult human population. The virus can reactivate from this latent infection into lytic replication for virus particle production. Here, we report that autophagic membranes, which engulf cytoplasmic constituents during macroautophagy and transport them to lysosomal degradation, are stabilized by lytic EBV replication in infected epithelial and B cells. Inhibition of autophagic membrane formation comprom...
Zweerink, H J; Corey, L
Virus-specific antibodies against a number of herpes simplex virus type 2 antigens were determined by radioimmunoprecipitation assays in sequential serum samples obtained from 12 patients with initial genital herpes simplex virus infection. The progressive appearance of antibodies to virus-specific antigens was observed; antibodies against a 130,000-molecular-weight glycoprotein complex appeared first, followed by antibodies against the major nucleocapsid polypeptide and then antibodies again...
Xu Feng; Zhao Chen; Li Yuhua; Li Jiang; Deng Youping; Shi Tieliu
Abstract Background Currently, several systems have been proposed to classify viruses and indicate the relationships between different ones, though each system has its limitations because of the complexity of viral origins and their rapid evolution rate. We hereby propose a new method to explore the relationships between different viruses. Method A new method, which is based on the virus-host protein-protein interaction network, is proposed in this paper to categorize viruses. The distances b...
Roux, Simon; Enault, Francois; Bronner, Gisèle; Vaulot, Daniel; Forterre, Patrick; Krupovic, Mart
Metagenomic studies have uncovered an astonishing diversity of ssDNA viruses encoding replication proteins (Reps) related to those of eukaryotic Circoviridae, Geminiviridae or Nanoviridae; however, exact evolutionary relationships among these viruses remain obscure. Recently, a unique chimeric virus (CHIV) genome, which has apparently emerged via recombination between ssRNA and ssDNA viruses, has been discovered. Here we report on the assembly of 13 new CHIV genomes recovered f...
Mihindukulasuriya, Kathie A.; Nguyen, Nang L.; Wu, Guang; Huang, Henry V.; Travassos da Rosa, Amelia P. A.; Popov, Vsevolod L.; Tesh, Robert B.; Wang, David
Here, we report the sequencing and classification of Nyamanini virus (NYMV) and Midway virus (MIDWV), two antigenically related viruses that were first isolated in 1957 and 1966, respectively. Although these viruses have been cultured multiple times from cattle egrets, seabirds, and their ticks, efforts to classify them taxonomically using conventional serological and electron microscopic approaches have failed completely. We used a random shotgun sequencing strategy to define the genomes of ...
Levy, D N; Refaeli, Y; Weiner, D B
The vpr gene product of human immunodeficiency virus (HIV) and simian immunodeficiency virus is a virion-associated regulatory protein that has been shown using vpr mutant viruses to increase virus replication, particularly in monocytes/macrophages. We have previously shown that vpr can directly inhibit cell proliferation and induce cell differentiation, events linked to the control of HIV replication, and also that the replication of a vpr mutant but not that of wild-type HIV type 1 (HIV-1) ...
Rose, J. K.; Doolittle, R. F.; Anilionis, A; Curtis, P J; Wunner, W H
We compared the predicted amino acid sequences of the vesicular stomatitis virus and rabies virus glycoproteins by using a computer program which provides an optimal alignment and a statistical significance for the match. Highly significant homology between these two proteins was detected, including identical positioning of one glycosylation site. A significant homology between the predicted amino acid sequences of vesicular stomatitis virus and influenza virus matrix proteins was also found.
Stavnezer, E; Gerhard, D S; Binari, R C; Balazs, I.
During serial passages of an avian leukosis virus (the transformation-defective, src deletion mutant of Bratislava 77 avian sarcoma virus, designated tdB77) in chicken embryo fibroblasts, viruses which transformed chicken embryo fibroblasts in vitro emerged. Chicken embryo fibroblasts infected with these viruses (SK770 and Sk780) had a distinctive morphology, formed foci in monolayer cultures, and grew independent of anchorage in semisolid agar. Bone marrow cells were not transformed by these...
Amann, Ralf; Rohde, Jörg; Wulle, Ulrich; Conlee, Douglas; Raue, Rudiger; Martinon, Olivier; Rziha, Hanns-Joachim
The present study describes the generation of a new Orf virus (ORFV) recombinant, D1701-V-RabG, expressing the rabies virus (RABV) glycoprotein that is correctly presented on the surface of infected cells without the need of replication or production of infectious recombinant virus. One single immunization with recombinant ORFV can stimulate high RABV-specific virus-neutralizing antibody (VNA) titers in mice, cats, and dogs, representing all nonpermissive hosts for the ORFV vector. The protec...
Full Text Available Oncolytic virotherapy has advanced since the days of its conception but therapeutic efficacy in the clinics does not seem to reach the same level as in animal models. One reason is premature oncolytic virus clearance in humans, which is a reasonable assumption considering the immune-stimulating nature of the oncolytic agents. However, several studies are beginning to reveal layers of restriction to oncolytic virotherapy that are present before an adaptive neutralizing immune response. Some of these barriers are present constitutively halting infection before it even begins, whereas others are raised by minute cues triggered by virus infection. Indeed, we and others have noticed that delivering viruses to tumors may not be the biggest obstacle to successful therapy, but instead the physical make-up of the tumor and its capacity to mount antiviral defenses seem to be the most important efficacy determinants. In this review, we summarize the constitutive and innate barriers to oncolytic virotherapy and discuss strategies to overcome them.
Kumar, Penmetcha K R
Viral diagnosis and surveillance are necessary steps in containing the spread of viral diseases, and they help in the deployment of appropriate therapeutic interventions. In the past, the commonly employed viral detection methods were either cell-culture or molecule-level assays. Most of these assays are laborious and expensive, require special facilities, and provide a slow diagnosis. To circumvent these limitations, biosensor-based approaches are becoming attractive, especially after the successful commercialization of glucose and other biosensors. In the present article, I have reviewed the current progress using the biosensor approach for detecting intact viruses. At the time of writing this review, three types of bioreceptor surfaces (antibody-, glycan-, and aptamer-based) have been explored on different sensing platforms for detecting intact viruses. Among these bioreceptors, aptamer-based sensors have been increasingly explored for detecting intact viruses using surface plasmon resonance (SPR) and other platforms. Special emphasis is placed on the aptamer-based SPR platform in the present review. PMID:27527230
Penmetcha K. R. Kumar
Full Text Available Viral diagnosis and surveillance are necessary steps in containing the spread of viral diseases, and they help in the deployment of appropriate therapeutic interventions. In the past, the commonly employed viral detection methods were either cell-culture or molecule-level assays. Most of these assays are laborious and expensive, require special facilities, and provide a slow diagnosis. To circumvent these limitations, biosensor-based approaches are becoming attractive, especially after the successful commercialization of glucose and other biosensors. In the present article, I have reviewed the current progress using the biosensor approach for detecting intact viruses. At the time of writing this review, three types of bioreceptor surfaces (antibody-, glycan-, and aptamer-based have been explored on different sensing platforms for detecting intact viruses. Among these bioreceptors, aptamer-based sensors have been increasingly explored for detecting intact viruses using surface plasmon resonance (SPR and other platforms. Special emphasis is placed on the aptamer-based SPR platform in the present review.
Simões e Silva AC
Full Text Available Ana Cristina Simões e Silva,1,2 Janaina Matos Moreira,1,2 Roberta Maia Castro Romanelli,2 Antonio Lucio Teixeira1,3 1Interdisciplinary Laboratory of Medical Investigation, 2Department of Pediatrics, Faculty of Medicine, Federal University of Minas Gerais (UFMG, Belo Horizonte, Brazil; 3Neuropsychiatry Program, Department of Psychiatry and Behavioral Sciences, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, USA Abstract: Before 2007, Zika virus (ZIKV was generally considered as an arbovirus of low clinical relevance, causing a mild self-limiting febrile illness in tropical Africa and Southeast Asia. Currently, a large, ongoing outbreak of ZIKV that started in Brazil in 2015 is spreading across the Americas. Virus infection during pregnancy has been potentially linked to congenital malformations, including microcephaly. In addition to congenital malformations, a temporal association between ZIKV infection and an increase in cases of Guillain–Barré syndrome is currently being observed in several countries. The mechanisms underlying these neurological complications are still unknown. Emerging evidence, mainly from in vitro studies, suggests that ZIKV may have direct effects on neuronal cells. The aim of this study was to critically review the literature available regarding the neurobiology of ZIKV and its potential neuropsychiatric manifestations. Keywords: Zika virus, microcephaly, Guillain–Barré syndrome, neurodevelopmental disorders
Siew Pheng Lim
Full Text Available The outbreak of West Nile virus (WNV in 1999 in the USA, and its continued spread throughout the Americas, parts of Europe, the Middle East and Africa, underscored the need for WNV antiviral development. Here, we review the current status of WNV drug discovery. A number of approaches have been used to search for inhibitors of WNV, including viral infection-based screening, enzyme-based screening, structure-based virtual screening, structure-based rationale design, and antibody-based therapy. These efforts have yielded inhibitors of viral or cellular factors that are critical for viral replication. For small molecule inhibitors, no promising preclinical candidate has been developed; most of the inhibitors could not even be advanced to the stage of hit-to-lead optimization due to their poor drug-like properties. However, several inhibitors developed for related members of the family Flaviviridae, such as dengue virus and hepatitis C virus, exhibited cross-inhibition of WNV, suggesting the possibility to re-purpose these antivirals for WNV treatment. Most promisingly, therapeutic antibodies have shown excellent efficacy in mouse model; one of such antibodies has been advanced into clinical trial. The knowledge accumulated during the past fifteen years has provided better rationale for the ongoing WNV and other flavivirus antiviral development.
Saiz, Juan-Carlos; Vázquez-Calvo, Ángela; Blázquez, Ana B.; Merino-Ramos, Teresa; Escribano-Romero, Estela; Martín-Acebes, Miguel A.
Since the beginning of this century, humanity has been facing a new emerging, or re-emerging, virus threat almost every year: West Nile, Influenza A, avian flu, dengue, Chikungunya, SARS, MERS, Ebola, and now Zika, the latest newcomer. Zika virus (ZIKV), a flavivirus transmitted by Aedes mosquitoes, was identified in 1947 in a sentinel monkey in Uganda, and later on in humans in Nigeria. The virus was mainly confined to the African continent until it was detected in south-east Asia the 1980’s, then in the Micronesia in 2007 and, more recently in the Americas in 2014, where it has displayed an explosive spread, as advised by the World Health Organization, which resulted in the infection of hundreds of thousands of people. ZIKV infection was characterized by causing a mild disease presented with fever, headache, rash, arthralgia, and conjunctivitis, with exceptional reports of an association with Guillain–Barre syndrome (GBS) and microcephaly. However, since the end of 2015, an increase in the number of GBS associated cases and an astonishing number of microcephaly in fetus and new-borns in Brazil have been related to ZIKV infection, raising serious worldwide public health concerns. Clarifying such worrisome relationships is, thus, a current unavoidable goal. Here, we extensively review what is currently known about ZIKV, from molecular biology, transmission routes, ecology, and epidemiology, to clinical manifestations, pathogenesis, diagnosis, prophylaxis, and public health. PMID:27148186
Glenn Wendy K
Full Text Available Abstract Background There is seemingly consistent and compelling evidence that there is no association between breastfeeding and breast cancer. An assumption follows that milk borne viruses cannot be associated with human breast cancer. We challenge this evidence because past breastfeeding studies did not determine "exposure" of newborn infants to colostrum and breast milk. Methods We conducted a prospective review of 100 consecutive births of infants in the same centre to determine the proportion of newborn infants who were "exposed" to colostrum or breast milk, as distinct from being fully breast fed. We also report a review of the breastfeeding practices of mothers of over 87,000 newborn infants in the Australian State of New South Wales. This study was approved by the Human Research Ethics Committee of the University of New South Wales (Sydney, Australia. Approval 05063, 29 September 2005. Results Virtually all (97 of 100 newborn infants in this centre were "exposed" to colostrum or breast milk whether or not they were fully breast fed. Between 82.2% to 98.7% of 87,000 newborn infants were "exposed" to colostrum or breast milk. Conclusion In some Western communities there is near universal exposure of new born infants to colostrum and breast milk. Accordingly it is possible for the transmission of human milk borne viruses. This is contrary to the widespread assumption that human milk borne viruses cannot be associated with breast cancer.
Ou, Shan-Chia; Giambrone, Joseph J
Infectious laryngotracheitis (ILT) is an important respiratory disease of chickens and annually causes significant economic losses in the poultry industry world-wide. ILT virus (ILTV) belongs to alphaherpesvirinae and the Gallid herpesvirus 1 species. The transmission of ILTV is via respiratory and ocular routes. Clinical and post-mortem signs of ILT can be separated into two forms according to its virulence. The characteristic of the severe form is bloody mucus in the trachea with high mortality. The mild form causes nasal discharge, conjunctivitis, and reduced weight gain and egg production. Conventional polymerase chain reaction (PCR), nested PCR, real-time PCR, and loop-mediated isothermal amplification were developed to detect ILTV samples from natural or experimentally infected birds. The PCR combined with restriction fragment length polymorphism (RFLP) can separate ILTVs into several genetic groups. These groups can separate vaccine from wild type field viruses. Vaccination is a common method to prevent ILT. However, field isolates and vaccine viruses can establish latent infected carriers. According to PCR-RFLP results, virulent field ILTVs can be derived from modified-live vaccines. Therefore, modified-live vaccine reversion provides a source for ILT outbreaks on chicken farms. Two recently licensed commercial recombinant ILT vaccines are also in use. Other recombinant and gene-deficient vaccine candidates are in the developmental stages. They offer additional hope for the control of this disease. However, in ILT endemic regions, improved biosecurity and management practices are critical for improved ILT control. PMID:24175219
Vimal Kumar Birendra
Full Text Available Mosquitoes transmit numerous arboviruses including dengue and chikungunya virus (CHIKV. Chikungunya is a re-emerging arthropod-borne viral disease caused by Chikungunya virus (CHIKV belonging to the Togaviridae family of genus Alphavirus. It is a virus with a single stranded, positive sense RNA, as its genome. It is maintained in a sylvatic and urban cycle involving humans and the mosquito species Aedes aegypti and Aedes albopictus. It has a major health impact on humans as it causes fever, rashes, arthralgia and myalgia. Polyarthralgia is the most important feature of CHIKV infection which primarily affects the small joints of the wrists and fingers along with the large joints like shoulders and knees. Currently, there are no vaccines or treatment regimens available for CHIKV infection. The molecular mechanism underlying the chronic polyarthralgia observed in patients is not well understood. The abundance of bacteria from the Enterobacteriaceae family increased with CHIKV infection whereas the abundance of known insect endosymbionts like Wolbachia and Blattabacterium decreased. In this review we have summarized the CHIKV organization, replication, epidemiology, clinical manifestations and pathogenesis with emphasis on the arthralgia.
Full Text Available Since the beginning of this century, humanity has been facing a new emerging, or re-emerging, virus threat almost every year: West Nile, Influenza A, avian flu, dengue, Chikungunya, SARS, MERS, Ebola, and now Zika, the latest newcomer. Zika virus (ZIKV, a flavivirus transmitted by Aedes mosquitoes, was identified in 1947 in a sentinel monkey in Uganda, and later on in humans in Nigeria. The virus was mainly confined to the African continent until it was detected in south-east Asia the 1980´s, then in the Micronesia in 2007 and, more recently in the Americas in 2014, where it has displayed an explosive spread, as advised by the World Health Organization (WHO, which resulted in the infection of hundreds of thousands of people. ZIKV infection was characterized by causing a mild disease presented with fever, headache, rash, arthralgia, and conjunctivitis, with exceptional reports of an association with Guillain-Barre syndrome (GBS and microcephaly. However, since the end of 2015, an increase in the number of GBS associated cases and an astonishing number of microcephaly in foetus and new-borns in Brazil have been related to ZIKV infection, raising serious worldwide public health concerns. Clarifying such worrisome relationships is, thus, a current unavoidable goal. Here, we extensively review what is currently known about ZIKV, from molecular biology, transmission routes, ecology and epidemiology, to clinical manifestations, pathogenesis, diagnosis, prophylaxis and public health.
Rossi, C P; Delcroix, M; Huitinga, I.; McAllister, A; Van Rooijen, N.; E. Claassen; Brahic, M
Theiler's virus, a murine picornavirus, causes a persistent infection of the central nervous system with chronic inflammation and primary demyelination. We examined the nature of infected cells at different times postinoculation (p.i.) with a combined immunocytochemistry-in situ hybridization assay. The virus was found in the gray matter of the brain, mostly in neurons, during the first week p.i. During the following weeks, the virus was present in the spinal cord, first in the gray and white...
Messina, Jane P; Kraemer, Moritz U.G.; Brady, Oliver J; Pigott, David M.; Shearer, Freya M.; Weiss, Daniel J.; Golding, Nick; Ruktanonchai, Corrine W; Gething, Peter W.; Cohn, Emily; John S Brownstein; Khan, Kamran; Tatem, Andrew J; Jaenisch, Thomas; Murray, Christopher J. L
Zika virus was discovered in Uganda in 1947 and is transmitted by Aedes mosquitoes, which also act as vectors for dengue and chikungunya viruses throughout much of the tropical world. In 2007, an outbreak in the Federated States of Micronesia sparked public health concern. In 2013, the virus began to spread across other parts of Oceania and in 2015, a large outbreak in Latin America began in Brazil. Possible associations with microcephaly and Guillain-Barré syndrome observed in this outbreak ...
Malone, Robert W.; Jane Homan; Michael V. Callahan; Jill Glasspool-Malone; Lambodhar Damodaran; Adriano de Bernardi Schneider; Rebecca Zimler; James Talton; Cobb, Ronald R; Ivan Ruzic; Julie Smith-Gagen; Daniel Janies; James Wilson
Introduction: Reports of high rates of primary microcephaly and Guillain–Barré syndrome associated with Zika virus infection in French Polynesia and Brazil have raised concerns that the virus circulating in these regions is a rapidly developing neuropathic, teratogenic, emerging infectious public health threat. There are no licensed medical countermeasures (vaccines, therapies or preventive drugs) available for Zika virus infection and disease. The Pan American Health Organization (PAHO) pred...
Carsten Münk; Jörg Zielonka
Lentiviruses are known for their narrow cell- and species-tropisms, which are determined by cellular proteins whose absence or presence either support viral replication (dependency factors, cofactors) or inhibit viral replication (restriction factors). Similar to Human immunodeficiency virus type 1 (HIV-1), the cat lentivirus Feline immunodeficiency virus (FIV) is sensitive to recently discovered cellular restriction factors from non-host species that are able to stop viruses from replicating...
Szomolanyi-Tsuda, Eva; Welsh, Raymond M.
The production of protective neutralizing antibodies occurs quickly in some viral infections but very slowly in others. In a new study, surface glycoproteins (the targets of neutralization) of 2 different viruses were genetically switched. Analysis of the neutralizing antibody response to each of the 2 parent and recombinant viruses in infected mice revealed that the speed of neutralizing antibody induction was intrinsically dependent on the surface glycoprotein and not the rest of the virus.
Zuniga, Armando; Wang, Zili; Liniger, Matthias; Hangartner, Lars; Caballero, Michael; Pavlovic, Jovan; Wild, Peter; Viret, Jean Francois; Glueck, Reinhard; Billeter, Martin A.; Naim, Hussein Y.
Live attenuated measles virus (MV) vaccines have an impressive record of safety, efficacy and ability to induce life-long immunity against measles infection. Using reverse genetics technology, such negative-strand RNA viruses can now be rescued from cloned DNA. This technology allows the insertion of exogenous genes encoding foreign antigens into the MV genome in such a way that they can be expressed by the MV vaccine strain, without affecting virus structure, propagation and cell targeting. ...
Francesco Piacente; Matteo Gaglianone; Maria Elena Laugieri; Tonetti, Michela G.
Glycosylation of surface molecules is a key feature of several eukaryotic viruses, which use the host endoplasmic reticulum/Golgi apparatus to add carbohydrates to their nascent glycoproteins. In recent years, a newly discovered group of eukaryotic viruses, belonging to the Nucleo-Cytoplasmic Large DNA Virus (NCLDV) group, was shown to have several features that are typical of cellular organisms, including the presence of components of the glycosylation machinery. Starting from initial observ...
Antunes, H; Macedo, M.; Estrada, A.
The hepatitis B virus is an important cause of morbidity and mortality in humans, thus making it a serious public health issue. The purpose of this study was to determine the hepatitis B virus vaccination rate with immunization, the risk of this population group becoming infected before vaccination and the prevalence of hepatitis B virus infection. The study involved randomly analyzing the serum of 311 adolescents of both sexes aged 14 from a total population of 536 adolescents attending scho...
Hasna Amdiouni; Hicham El Rhaffouli
Filoviruses, including Ebola and Marburg viruses, are recognized as a significant warning to public health. They are zoonotic agents with bats as primary reservoir. Those viruses can cause severe human infection with hemorrhagic syndrome leading to death. The mortality rate can be higher than 90%. In West Africa, recent Ebola virus outbreak occurred in March 2014, has caused more than 8300 infections with more than 4000 deaths. That shows the critical state of this country, and...
Shaw, Megan L.; Stone, Kathryn L.; Colangelo, Christopher M.; Gulcicek, Erol E.; Peter Palese
Virions are thought to contain all the essential proteins that govern virus egress from the host cell and initiation of replication in the target cell. It has been known for some time that influenza virions contain nine viral proteins; however, analyses of other enveloped viruses have revealed that proteins from the host cell can also be detected in virions. To address whether the same is true for influenza virus, we used two complementary mass spectrometry approaches to perform a comprehensi...
Tao Dong; Xing He; Mei Peng; Junjian Huang
Based on that the computer will be infected by infected computer and exposed computer, and some of the computers which are in suscepitible status and exposed status can get immunity by antivirus ability, a novel coumputer virus model is established. The dynamic behaviors of this model are investigated. First, the basic reproduction number R0, which is a threshold of the computer virus spreading in internet, is determined. Second, this model has a virus-free equilibrium P0, which means that th...
Mahony, James B.
Summary: Clinical laboratories historically diagnose seven or eight respiratory virus infections using a combination of techniques including enzyme immunoassay, direct fluorescent antibody staining, cell culture, and nucleic acid amplification tests. With the discovery of six new respiratory viruses since 2000, laboratories are faced with the challenge of detecting up to 19 different viruses that cause acute respiratory disease of both the upper and lower respiratory tracts. The application o...
Bushell, Martin; Sarnow, Peter
As invading viruses do not harbor functional ribosomes in their virions, successful amplification of the viral genomes requires that viral mRNAs compete with cellular mRNAs for the host cell translation apparatus. Several RNA viruses have evolved remarkable strategies to recruit the host translation initiation factors required for the first steps in translation initiation by host cell mRNAs. This review describes the ways that three families of RNA viruses effectively usurp limiting translati...
Biegel, Jason M; Pager, Cara T
During infection, positive-strand RNA viruses subvert cellular machinery involved in RNA metabolism to translate viral proteins and replicate viral genomes to avoid or disable the host defense mechanisms. Cytoplasmic RNA granules modulate the stabilities of cellular and viral RNAs. Understanding how hepatitis C virus and other flaviviruses interact with the host machinery required for protein synthesis, localization, and degradation of mRNAs is important for elucidating how these processes occur in both virus-infected and uninfected cells. PMID:26937026
Malone, Robert W.; Jane Homan; Michael V Callahan; Jill Glasspool-Malone; Lambodhar Damodaran; Adriano de Bernardi Schneider; Rebecca Zimler; James Talton; Cobb, Ronald R; Ivan Ruzic; Julie Smith-Gagen; Daniel Janies; James Wilson
Reports of high rates of primary microcephaly and Guillain-Barré syndrome associated with Zika virus infection in French Polynesia and Brazil have raised concerns that the virus circulating in these regions is a rapidly developing neuropathic, teratogenic, emerging infectious public health threat. There are no licensed medical countermeasures (vaccines, therapies or preventive drugs) available for Zika virus infection and disease. The Pan American Health Organization (PAHO) predicts that Zika...
Foot-and-mouth disease virus (FMDV), equine rhinitis A virus (ERAV) and bovine rhinitis B virus (BRBV) comprise the genus Aphthovirus of the Picornaviridae family. Seven genera within this family, Aphthoviruses, Cardioviruses, Erboviruses (ERBV), Kobuviruses, Senecaviruses, Sapeloviruses, and Tescho...
Turner, Judith Axler
Computer viruses are programs that propagate themselves from disk to disk and destroy programs or information files. Several universities have recently reported virus outbreaks. Some suggestions for avoiding the viruses are provided. (MLW)
de Virgiliis, S; Frau, F; Sanna, G.; Turco, M P; Figus, A L; Cornacchia, G; Cao, A.
Maternal transmission of hepatitis B virus infection in relation to the hepatitis B e antigen/antibody system and serum hepatitis B virus-DNA were evaluated. Results indicate that hepatitis B virus-DNA analysis can identify hepatitis B serum antigen positive mothers who may transmit infection to their offspring.
Smith, Donald B.; Gaunt, Eleanor R.; Digard, Paul; Templeton, Kate; Simmonds, Peter
Highlights • “Influenza D” virus was not detected in Scottish respiratory samples (n = 3000). • Influenza C virus infection was present in 0.2% of respiratory samples. • Six influenza C virus complete genomes were sequenced. • Influenza C isolates comprised multiple, reassortant lineages.
Ayala Nunez, Vanesa; Wilschut, Jan; Smit, Jolanda M.
A variety of approaches can be applied to investigate the multiple steps and interactions that occur during virus entry into the host cell. Single-virus tracking is a powerful real-time imaging technique that offers the possibility to monitor virus-cell binding, internalization, intracellular traffi