Modelling local dispersal of Bluetongue virus serotype 8 using random walk.

NARCIS (Netherlands)

Gerbier, G.; Baldet, T.; Tran, A.; Hendrickx, G.; Guis, H.; Mintiens, K.; Elbers, A.R.W.; Staubach, C.

2008-01-01

The knowledge of the place where a disease is first introduced and from where it later spreads is a key element for the understanding of an epizootic. For a contagious disease, the main method is back tracing. For a vector-borne disease such as the Bluetongue virus serotype 8 epizootic that occurred

Financial Evaluation of Different Vaccination Strategies for Controlling the Bluetongue Virus Serotype 8 Epidemic in the Netherlands in 2008

NARCIS (Netherlands)

Velthuis, A.G.J.; Mourits, M.C.M.; Saatkamp, H.W.; Koeijer, de A.; Elbers, A.R.W.

2011-01-01

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

Evaluation of cross-protection of bluetongue virus serotype 4 with other serotypes in sheep

Directory of Open Access Journals (Sweden)

Gcwalisile B. Zulu

2014-10-01

Full Text Available Bluetongue (BT is a non-contagious disease of sheep and other domestic and wild ruminants caused by the bluetongue virus (BTV. Currently 26 serotypes of the virus have been identified. In South Africa, 22 serotypes have been identified and BT is controlled mainly by annual vaccinations using a freeze-dried live attenuated polyvalent BTV vaccine. The vaccine is constituted of 15 BTV serotypes divided into three separate bottles and the aim is to develop a vaccine using fewer serotypes without compromising the immunity against the disease. This study is based on previously reported cross-neutralisation of specific BTV serotypes in in vitro studies. Bluetongue virus serotype 4 was selected for this trial and was tested for cross-protection against serotype 4 (control, 1 (unrelated serotype, 9, 10 and 11 in sheep using the serum neutralisation test. The purpose of the study was to determine possible cross-protection of different serotypes in sheep. Of those vaccinated with BTV-4 and challenged with BTV-1, which is not directly related to BTV-4, 20% were completely protected and 80% showed clinical signs, but the reaction was not as severe as amongst the unvaccinated animals. In the group challenged with BTV-10, some showed good protection and some became very sick. Those challenged with BTV-9 and BTV-11 had good protection. The results showed that BTV-4 does not only elicit a specific immune response but can also protect against other serotypes.

The molecular biology of Bluetongue virus replication.

Science.gov (United States)

Patel, Avnish; Roy, Polly

2014-03-01

The members of Orbivirus genus within the Reoviridae family are arthropod-borne viruses which are responsible for high morbidity and mortality in ruminants. Bluetongue virus (BTV) which causes disease in livestock (sheep, goat, cattle) has been in the forefront of molecular studies for the last three decades and now represents the best understood orbivirus at a molecular and structural level. The complex nature of the virion structure has been well characterised at high resolution along with the definition of the virus encoded enzymes required for RNA replication; the ordered assembly of the capsid shell as well as the protein and genome sequestration required for it; and the role of host proteins in virus entry and virus release. More recent developments of Reverse Genetics and Cell-Free Assembly systems have allowed integration of the accumulated structural and molecular knowledge to be tested at meticulous level, yielding higher insight into basic molecular virology, from which the rational design of safe efficacious vaccines has been possible. This article is centred on the molecular dissection of BTV with a view to understanding the role of each protein in the virus replication cycle. These areas are important in themselves for BTV replication but they also indicate the pathways that related viruses, which includes viruses that are pathogenic to man and animals, might also use providing an informed starting point for intervention or prevention. Copyright © 2014 Elsevier B.V. All rights reserved.

Identification and characterization of a novel non-structural protein of bluetongue virus.

Directory of Open Access Journals (Sweden)

Maxime Ratinier

2011-12-01

Full Text Available Bluetongue virus (BTV is the causative agent of a major disease of livestock (bluetongue. For over two decades, it has been widely accepted that the 10 segments of the dsRNA genome of BTV encode for 7 structural and 3 non-structural proteins. The non-structural proteins (NS1, NS2, NS3/NS3a play different key roles during the viral replication cycle. In this study we show that BTV expresses a fourth non-structural protein (that we designated NS4 encoded by an open reading frame in segment 9 overlapping the open reading frame encoding VP6. NS4 is 77-79 amino acid residues in length and highly conserved among several BTV serotypes/strains. NS4 was expressed early post-infection and localized in the nucleoli of BTV infected cells. By reverse genetics, we showed that NS4 is dispensable for BTV replication in vitro, both in mammalian and insect cells, and does not affect viral virulence in murine models of bluetongue infection. Interestingly, NS4 conferred a replication advantage to BTV-8, but not to BTV-1, in cells in an interferon (IFN-induced antiviral state. However, the BTV-1 NS4 conferred a replication advantage both to a BTV-8 reassortant containing the entire segment 9 of BTV-1 and to a BTV-8 mutant with the NS4 identical to the homologous BTV-1 protein. Collectively, this study suggests that NS4 plays an important role in virus-host interaction and is one of the mechanisms played, at least by BTV-8, to counteract the antiviral response of the host. In addition, the distinct nucleolar localization of NS4, being expressed by a virus that replicates exclusively in the cytoplasm, offers new avenues to investigate the multiple roles played by the nucleolus in the biology of the cell.

Using remote sensing and machine learning for the spatial modelling of a bluetongue virus vector

Science.gov (United States)

Van doninck, J.; Peters, J.; De Baets, B.; Ducheyne, E.; Verhoest, N. E. C.

2012-04-01

Bluetongue is a viral vector-borne disease transmitted between hosts, mostly cattle and small ruminants, by some species of Culicoides midges. Within the Mediterranean basin, C. imicola is the main vector of the bluetongue virus. The spatial distribution of this species is limited by a number of environmental factors, including temperature, soil properties and land cover. The identification of zones at risk of bluetongue outbreaks thus requires detailed information on these environmental factors, as well as appropriate epidemiological modelling techniques. We here give an overview of the environmental factors assumed to be constraining the spatial distribution of C. imicola, as identified in different studies. Subsequently, remote sensing products that can be used as proxies for these environmental constraints are presented. Remote sensing data are then used together with species occurrence data from the Spanish Bluetongue National Surveillance Programme to calibrate a supervised learning model, based on Random Forests, to model the probability of occurrence of the C. imicola midge. The model will then be applied for a pixel-based prediction over the Iberian peninsula using remote sensing products for habitat characterization.

Enhanced infectivity of bluetongue virus in cell culture by centrifugation.

OpenAIRE

Sundin, D R; Mecham, J O

1989-01-01

The effects of centrifugation of the infection of cell culture with bluetongue virus (BTV) were investigated. Baby hamster kidney cells were infected with BTV with or without centrifugation. Viral antigen was detected by immunofluorescence at 24 h in both centrifuged and noncentrifuged cultures. However, after 24 h of infection, the production of PFU in centrifuged cell cultures was 10- to 20-fold greater than that seen in cultures not centrifuged. In addition, centrifugation enhanced the dir...

Validation of a commercial ELISA for the detection of bluetongue virus (BTV) specific antibodies in individual milk samples of Dutch dairy cows

NARCIS (Netherlands)

Kramps, J.A.; Maanen, van K.; Mars, M.H.; Popma, J.K.; Rijn, van P.A.

2008-01-01

recently developed indirect ELISA for the detection of bluetongue virus (BTV)-specific antibodies in bovine milk samples was compared to that of the routinely used competitive ELISA on serum samples. During the bluetongue outbreak in the Netherlands in 2006, caused by BTV serotype 8, coupled serum

Structural constraints in the packaging of bluetongue virus genomic segments

OpenAIRE

Burkhardt, Christiane; Sung, Po-Yu; Celma, Cristina C.; Roy, Polly

2014-01-01

: The mechanism used by bluetongue virus (BTV) to ensure the sorting and packaging of its 10 genomic segments is still poorly understood. In this study, we investigated the packaging constraints for two BTV genomic segments from two different serotypes. Segment 4 (S4) of BTV serotype 9 was mutated sequentially and packaging of mutant ssRNAs was investigated by two newly developed RNA packaging assay systems, one in vivo and the other in vitro. Modelling of the mutated ssRNA followed by bioche...

Transplacental transmission of Bluetongue virus serotype 8 in ewes in early and mid gestation

NARCIS (Netherlands)

Sluijs, van der M.; Timmermans, M.; Moulin, V.; Vonk Noordegraaf, C.; Vrijenhoek, M.; Debyser, I.; Smit, de A.J.; Moormann, R.J.M.

2011-01-01

The ability of Bluetongue virus serotype 8 (BTV-8) originating from the 2006 European outbreak to cross the ovine placenta during early and mid gestation was investigated in two separate experiments. In the first experiment, 16 ewes were infected with BTV-8 at 70–75 days gestation. The foetuses were

Transplacental Transmission of Bluetongue Virus Serotype 1 and Serotype 8 in Sheep: Virological and Pathological Findings

NARCIS (Netherlands)

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.

2013-01-01

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

Transplacental and oral transmission of wild-type bluetongue virus serotype 8 in cattle after experimental infection

NARCIS (Netherlands)

Backx, A.; Heutink, C.G.; Rooij, van E.M.A.; Rijn, van P.A.

2009-01-01

Potential vertical transmission of wild-type bluetongue virus serotype 8 (BTV-8) in cattle was explored in this experiment. We demonstrated transplacental transmission of wild-type BTV-8 in one calf and oral infection with BTV-8 in another calf. Following the experimental BTV-8 infection of seven

Did vaccination slow the spread of bluetongue in France?

Directory of Open Access Journals (Sweden)

Maryline Pioz

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.

9 CFR 113.303 - Bluetongue Vaccine.

Science.gov (United States)

2010-01-01

... 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. (2...

Economics of vaccinating extensively managed sheep flocks against Bluetongue disease

Science.gov (United States)

Bluetongue is a serious and recurring threat to sheep producers throughout the world. In the western United States, bluetongue virus (BTV) is transmitted by biting midges in late summer and early autumn, just before lambs are sent to market. No vaccine is currently sold for the most common serotype ...

Mapping the basic reproduction number (Ro) for vector-borne diseases: A case study on bluetongue virus.

NARCIS (Netherlands)

Hartemink, N.; Purse, B.V.; Meiswinkel, R.; Brown, H.E.; Koeijer, de A.A.; Elbers, A.R.W.; Boender, G.J.; Rogers, D.J.; Heesterbeek, J.A.P.

2009-01-01

Geographical maps indicating the value of the basic reproduction number, R0, can be used to identify areas of higher risk for an outbreak after an introduction. We develop a methodology to create R0 maps for vector-borne diseases, using bluetongue virus as a case study. This method provides a tool

European bluetongue serotype 8

NARCIS (Netherlands)

Drolet, Barbara S.; Reister-Hendricks, Lindsey M.; Podell, Brendan K.; Breitenbach, Jonathan E.; Mcvey, D.S.; Rijn, van Piet A.; Bowen, Richard A.

2016-01-01

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

Experimental infection of South American camelids with bluetongue virus serotype 8.

Science.gov (United States)

Schulz, Claudia; Eschbaumer, Michael; Rudolf, Miriam; König, Patricia; Keller, Markus; Bauer, Christian; Gauly, Matthias; Grevelding, Christoph G; Beer, Martin; Hoffmann, Bernd

2012-01-27

Bluetongue (BT) is an infectious, non-contagious disease of wild and domestic ruminants. It is caused by bluetongue virus (BTV) and transmitted by Culicoides biting midges. Since 1998, BT has been emerging throughout Europe, threatening not only the naïve ruminant population. Historically, South American camelids (SAC) were considered to be resistant to BT disease. However, recent fatalities related to BTV in captive SAC have raised questions about their role in BTV epidemiology. Data on the susceptibility of SAC to experimental infection with BTV serotype 8 (BTV-8) were collected in an animal experiment. Three alpacas (Vicugna pacos) and three llamas (Lama glama) were experimentally infected with BTV-8. They displayed very mild clinical signs. Seroconversion was first measured 6-8 days after infection (dpi) by ELISA, and neutralising antibodies appeared 10-13 dpi. BTV-8 RNA levels in blood were very low, and quickly cleared after seroconversion. However, spleens collected post-mortem were still positive for BTV RNA, over 71 days after the last detection in blood samples. Virus isolation was only possible from blood samples of two alpacas by inoculation of highly sensitive interferon alpha/beta receptor-deficient (IFNAR(-/-)) mice. An in vitro experiment demonstrated that significantly lower amounts of BTV-8 adsorb to SAC blood cells than to bovine blood cells. Although this experiment showed that SAC are generally susceptible to a BTV-8 infection, it indicates that these species play a negligible role in BTV epidemiology. Copyright © 2011 Elsevier B.V. All rights reserved.

Bluetongue virus in Lebanon.

Science.gov (United States)

El Hage, J; Lorusso, A; Carmine, I; Di Gennaro, A; Portanti, O; Olivieri, S; Casaccia, C; Pisciella, M; Teodori, L; Sghaier, S; Savini, G

2013-10-01

Since 2000, several incursions of bluetongue virus (BTV) occurred in the Mediterranean Basin involving European and surrounding Countries. The Middle East represents one of the most important gateways for the access of BTV in Europe. Limited data on the BTV situation in this area are available. In this perspective, an epidemiological survey on the presence of BTV in Lebanon was conducted. Of the 181 serum samples tested, 97 (mean = 53.6%; 95% CI: 46.3-60.7) resulted positive when tested for the presence of BTV antibodies by c-ELISA, of these 42 (mean = 42%; 95% CI: 32.8-51.8) serum samples were from sheep and 55 (mean = 67.9%; 95% CI: 57.1-77.1) serum samples were from goats. Fourteen blood samples (14/110; mean = 12.7%; 95% CI: 7.8-20.3), 6 (6/66; mean = 9.1%; 95% CI: 4.4-18.5) from sheep and 8 (8/44; mean = 18.2%; 95% CI: 9.6-32.0) from goats, were positive by qRT-PCR. The results with serum-neutralization assay and typing performed by RT-PCR confirmed that six BTV serotypes are currently circulating in Lebanon, and these serotypes are as follows: 1, 4, 6, 8, 16 and 24. This study is the first report that confirms the presence and circulation of BTV in Lebanon. © 2013 Blackwell Verlag GmbH.

The effect of temperature on the in vitro transcriptase reaction of bluetongue virus, epizootic haemorrhagic disease virus and African horsesickness virus

International Nuclear Information System (INIS)

Van Dijk, A.A.; Huismans, H.

1982-01-01

Virions of bluetongue virus (BTV), epizootic haemorrhagic disease virus (EHDV) and African horsesickness virus (AHSV) can be converted to core particles by treatment with chymotrypsin and magnesium. The conversion is characterized by the removal of the 2 outer capsid polypeptides of the virion. The loss of these 2 proteins results in an increase in density from 1,36 g/ml to 1,40 g/ml on CsCl gradients. The BTV, EHDV and AHSV core particles have an associated double-stranded RNA dependent RNA transcriptase that appears to transcribe mRNA optimally at 28 degrees Celsius. It was found, at least in the case of BTV, that this low temperature preference is not an intrinsic characteristic of the transcriptase, but is due to a temperature-dependent inhibition of transcription at high core concentrations

Sero-prevalence study of bluetongue infection in sheep and goats in ...

African Journals Online (AJOL)

Bluetongue is an infectious, a non-contagious, arthropod borne viral disease of ruminants and has been reported from most of the tropical and subtropical regions of the world. Seroprevalence study was carried from July, 2013 to January, 2015 to understand bluetongue virus infection in selected areas of sheep and

PREVALENCE OF BOVINE HERPESVIRUS-1,PARAINFLUENZA-3,BOVINE ROTAVIRUS, BOVINE VIRAL DIARRHEA, BOVINE ADENOVIRUS-7,BOVINE LEUKEMIA VIRUS AND BLUETONGUE VIRUS ANTIBODIES IN CATTLE IN MEXICO

OpenAIRE

SUZAN, Victor M.; ONUMA, Misao; AGUILAR, Romero E.; MURAKAMI, Yosuke

1983-01-01

Sera were collected from dairy and beef cattle in 19 different states of Mexico. These sera were tested for bovine herpesvirus-1 (BHV-1), parainfluenza-3 virus (PIV-3), bovine rotavirus (BRV), bovine leukemia virus (BLV), bovine adenovirus-7 (BAV-7), bluetongue virus (BTV) and bovine viral diarrhea virus (BVDV). Seropositive rates for each virus for dairy cattle tested were 158/277(57.0%) for BHV-1,217/286(75.0%) for PIV-3,541/1498(36.1%) for BLV, 134/144(93.1%) for BRV, 39/90(43.3%) for BTV,...

Seroprevalence of bluetongue disease in sheep in west and northwest provinces of Iran

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Mohammad Khezri

2013-09-01

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%.

Standardization and application of real-time polymerase chain reaction for rapid detection of bluetongue virus

Directory of Open Access Journals (Sweden)

I. Karthika Lakshmi

2018-04-01

Full Text Available Aim: The present study was designed to standardize real-time polymerase chain reaction (PCR for detecting the bluetongue virus from blood samples of sheep collected during outbreaks of bluetongue disease in the year 2014 in Andhra Pradesh and Telangana states of India. Materials and Methods: A 10-fold serial dilution of Plasmid PUC59 with bluetongue virus (BTV NS3 insert was used to plot the standard curve. BHK-21 and KC cells were used for in vitro propagation of virus BTV-9 at a TCID50/ml of 105 ml and RNA was isolated by the Trizol method. Both reverse transcription -PCR and real-time PCR using TaqMan probe were carried out with RNA extracted from virus-spiked culture medium and blood to compare the sensitivity by means of finding out the limit of detection (LoD. The results were verified by inoculating the detected and undetected dilutions onto cell cultures with further cytological (cytopathic effect and molecular confirmation (by BTV-NS1 group-specific PCR. The standardized technique was then applied to field samples (blood for detecting BTV. Results: The slope of the standard curve obtained was -3.23, and the efficiency was 103%. The LoD with RT-PCR was 8.269Ex103 number of copies of plasmid, whereas it was 13 with real-time PCR for plasmid dilutions. Similarly, LoD was determined for virus-spiked culture medium, and blood with both the types of PCR and the values were 103 TCID 50/ml and 104 TCID 50/ml with RT-PCR and 10° TCID 50/ml and 102 TCID 50/ml with real-time PCR, respectively. The standardized technique was applied to blood samples collected from BTV suspected animals; 10 among 20 samples were found positive with Cq values ranging from 27 to 39. The Cq value exhibiting samples were further processed in cell cultures and were confirmed to be BT positive. Likewise, Cq undetected samples on processing in cell cultures turned out to be BTV negative. Conclusion: Real-time PCR was found to be a very sensitive as well as reliable method

Deep sequencing as a method of typing bluetongue virus isolates.

Science.gov (United States)

Rao, Pavuluri Panduranga; Reddy, Yella Narasimha; Ganesh, Kapila; Nair, Shreeja G; Niranjan, Vidya; Hegde, Nagendra R

2013-11-01

Bluetongue (BT) is an economically important endemic disease of livestock in tropics and subtropics. In addition, its recent spread to temperate regions like North America and Northern Europe is of serious concern. Rapid serotyping and characterization of BT virus (BTV) is an essential step in the identification of origin of the virus and for controlling the disease. Serotyping of BTV is typically performed by serum neutralization, and of late by nucleotide sequencing. This report describes the near complete genome sequencing and typing of two isolates of BTV using Illumina next generation sequencing platform. Two of the BTV RNAs were multiplexed with ten other unknown samples. Viral RNA was isolated and fragmented, reverse transcribed, the cDNA ends were repaired and ligated with a multiplex oligo. The genome library was amplified using primers complementary to the ligated oligo and subjected to single and paired end sequencing. The raw reads were assembled using a de novo method and reference-based assembly was performed based on the contig data. Near complete sequences of all segments of BTV were obtained with more than 20× coverage, and single read sequencing method was sufficient to identify the genotype and serotype of the virus. The two viruses used in this study were typed as BTV-1 and BTV-9E. Copyright © 2013 Elsevier B.V. All rights reserved.

Culicoides and the global epidemiology of bluetongue virus infection.

Science.gov (United States)

Tabachnick, W J

2004-01-01

The distribution of the bluetongue viruses (BTV) is limited to geographic areas containing competent vector species. All BTV-competent species belong to the genus Culicoides. In the New World, two different BTV epidemiological systems (episystems) occur. Culicoides sonorensis is responsible for transmitting BTV serotypes in North America that differ from South American serotypes transmitted by C. insignis. There are other episystems in the world. The role of different Culicoides vector species and the underlying mechanisms governing their vector capacity for BTV are unknown. It is likely that these vary between Culicoides species and episystems. As a result, our ability to predict and/or mitigate BTV in different episystems will remain problematic. Several complex issues need to be resolved to provide risk assessment and mitigation for BTV. This will require a substantial investment in new research paradigms that investigate details of underlying controlling mechanisms in several species of Culicoides.

Susceptibility of in vitro produced hatched bovine blastocysts to infection with bluetongue virus serotype 8

Directory of Open Access Journals (Sweden)

Vandaele Leen

2011-01-01

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.

Farmers' Preferences For Bluetongue Vaccination Scheme Attributes

NARCIS (Netherlands)

Sok, Jaap; Lans, van der Ivo A.; Hogeveen, Henk; Elbers, Armin R.W.; Oude Lansink, Alfons G.J.M.

2017-01-01

Re-emergence of the bluetongue disease in Europe poses a continuous threat to European livestock production. Large-scale vaccination is the most effective intervention to control virus spread. Compared to command-and-control approaches, voluntary vaccination approaches can be effective at lower

Breeding sites and species association of the main Bluetongue and Schmallenberg virus vectors, the Culicoides species (Diptera: Ceratopogonidae), in northern Europe

OpenAIRE

Zimmer, Jean-Yves; Losson, Bertrand; Saegerman, Claude; Haubruge, Eric; Francis, Frédéric

2013-01-01

Several species of Culicoides (Diptera: Ceratopogonidae) biting midges are biological vectors of bluetongue virus (BTV) and, as recently discovered, Schmallenberg virus (SBV) in northern Europe. Since their recent emergence in this part of the continent, these diseases that affect domestic and wild ruminants have caused considerable economic losses to the sheep and cattle industries. The substrates that are suitable for larval development of the main vector species are still relatively unknow...

Bluetongue Disabled Infectious Single Animal (DISA) vaccine: Studies on the optimal route and dose in sheep

NARCIS (Netherlands)

Rijn, van P.A.; Daus, F.J.; Maris-Veldhuis, M.A.; Feenstra, Femke; Gennip, van H.G.P.

2016-01-01

Bluetongue (BT) is a disease of ruminants caused by bluetongue virus (BTV) transmitted by biting midges of the Culicoides genus. Outbreaks have been controlled successfully by vaccination, however, currently available BT vaccines have several shortcomings. Recently, we have developed BT Disabled

Novel serotype of bluetongue virus in South America and first report of epizootic haemorrhagic disease virus in Ecuador.

Science.gov (United States)

Verdezoto, J; Breard, E; Viarouge, C; Quenault, H; Lucas, P; Sailleau, C; Zientara, S; Augot, D; Zapata, S

2018-02-01

Bluetongue virus (BTV) and Epizootic haemorrhagic disease virus (EHDV) are closely related Orbiviruses that affect domestic and wild ruminants. In Ecuador previous serological studies reported the presence of BTV; however, no data are available about the presence of EHDV. In this study, 295 cattle without symptoms of infection were sampled from two farms located in Andean and Amazonian regions and from a slaughterhouse in the coastal region. ELISA analyses showed high prevalence of BTV (98.9%) and EHDV (81.3%) antibodies, and RT-qPCRs revealed the presence of EHDV (24.1%) and BTV (10.2%) genomes in cattle blood samples. Viral isolation allowed to identify EHDV serotype 1 (EHDV1) and BTV serotypes 9 (BTV9), 13 and 18. These findings suggest that BTV and EHDV are enzootic diseases in Ecuador. © 2017 Blackwell Verlag GmbH.

Transient Bluetongue virus serotype 8 capsid protein expression in Nicotiana benthamiana

Directory of Open Access Journals (Sweden)

Albertha R. van Zyl

2016-03-01

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.

Antigenic profile of African horse sickness virus serotype 4 VP5 and identification of a neutralizing epitope shared with bluetongue virus and epizootic hemorrhagic disease virus

DEFF Research Database (Denmark)

Martinez-Torrecuadrada, J.L.; Langeveld, J.P.M.; Venteo, A.

1999-01-01

African horse sickness virus (AHSV) causes a fatal disease in horses. The virus capsid is composed of a double protein layer, the outermost of which is formed by two proteins: VP2 and VP5. VP2 is known to determine the serotype of the virus and to contain the neutralizing epitopes. The biological...... in a plaque reduction assay were generated. To dissect the antigenic structure of AHSV VP5, the protein was cloned in Escherichia coil using the pET3 system. The immunoreactivity of both MAbs, and horse and rabbit polyclonal antisera, with 17 overlapping fragments from VP5 was analyzed. The most....... 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...

The use of recombinant DNA technology for the development of a bluetongue virus subunit vaccine

International Nuclear Information System (INIS)

Huismans, H.

1985-01-01

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 32 P-labelled DNA probe made with BTV-m RNA as template. Possible strategies for the development of a bluetongue virus submit vaccine are discussed

Financial evaluation of different vaccination strategies for controlling the bluetongue virus serotype 8 epidemic in The Netherlands in 2008.

Science.gov (United States)

Velthuis, Annet G J; Mourits, Monique C M; Saatkamp, Helmut W; de Koeijer, Aline A; Elbers, Armin R W

2011-05-04

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. 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. This study demonstrates that a financial analysis differentiates between vaccination strategies and indicates important decision rules based on efficiency.

Reverse transcription loop-mediated isothermal amplification assays for rapid identification of eastern and western strains of bluetongue virus in India.

Science.gov (United States)

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

2016-08-01

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

Sources of variation in an enzyme-linked immunoassay of bluetongue virus in Culicoides variipennis (Diptera: Ceratopogonidae).

Science.gov (United States)

Tabachnick, W J; Mecham, J O

1991-03-01

An enzyme-linked immunoassay for detecting bluetongue virus in infected Culicoides variipennis was evaluated using a nested analysis of variance to determine sources of experimental error in the procedure. The major source of variation was differences among individual insects (84% of the total variance). Storing insects at -70 degrees C for two months contributed to experimental variation in the ELISA reading (14% of the total variance) and should be avoided. Replicate assays of individual insects were shown to be unnecessary, since variation among replicate wells and plates was minor (2% of the total variance).

Financial evaluation of different vaccination strategies for controlling the bluetongue virus serotype 8 epidemic in The Netherlands in 2008.

Directory of Open Access Journals (Sweden)

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.

Development of a real-time RT-PCR assay based on primer-probe energy transfer for the detection of all serotypes of bluetongue virus

DEFF Research Database (Denmark)

Leblanc, N; Rasmussen, Thomas Bruun; Fernandez, J

2010-01-01

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...

Expected Net Benefit of Vaccinating Rangeland Sheep against Bluetongue Virus Using a Modified-Live versus Killed Virus Vaccine.

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Munsick, Tristram R; Peck, Dannele E; Ritten, John P; Jones, Randall; Jones, Michelle; Miller, Myrna M

2017-01-01

Recurring outbreaks of bluetongue virus in domestic sheep of the US Intermountain West have prompted questions about the economic benefits and costs of vaccinating individual flocks against bluetongue (BT) disease. We estimate the cost of a BT outbreak on a representative rangeland sheep operation in the Big Horn Basin of the state of Wyoming using enterprise budgets and stochastic simulation. The latter accounts for variability in disease severity and lamb price, as well as uncertainty about when an outbreak will occur. We then estimate the cost of purchasing and administering a BT vaccine. Finally, we calculate expected annual net benefit of vaccinating under various outbreak intervals. Expected annual net benefit is calculated for both a killed virus (KV) vaccine and modified-live virus vaccine, using an observed price of $0.32 per dose for modified-live and an estimated price of $1.20 per dose for KV. The modified-live vaccine's expected annual net benefit has a 100% chance of being positive for an outbreak interval of 5, 10, or 20 years, and a 77% chance of being positive for a 50-year interval. The KV vaccine's expected annual net benefit has a 97% chance of being positive for a 5-year outbreak interval, and a 42% chance of being positive for a 10-year interval. A KV vaccine is, therefore, unlikely to be economically attractive to producers in areas exposed less frequently to BT disease. A modified-live vaccine, however, requires rigorous authorization before legal use can occur in Wyoming. To date, no company has requested to manufacture a modified-live vaccine for commercial use in Wyoming. The KV vaccine poses less risk to sheep reproduction and less risk of unintentional spread, both of which facilitate approval for commercial production. Yet, our results show an economically consequential tradeoff between a KV vaccine's relative safety and higher cost. Unless the purchase price is reduced below our assumed $1.20 per dose, producer adoption of a KV

Bluetongue, Schmallenberg - what is next? Culicoides-borne viral diseases in the 21st Century

NARCIS (Netherlands)

Koenraadt, C.J.M.; Balenghien, T.; Carpenter, S.; Ducheyne, E.; Elbers, A.R.W.; Fife, M.; Garros, C.; Ibanez-Justicia, A.; Kampen, H.; Kormelink, R.J.M.; Losson, B.; Poel, van der W.H.M.; Regge, de N.; Rijn, van P.A.; Sanders, C.; Schaffner, F.; Sloet van Oldruitenborgh-Oosterbaan, M.M.; Takken, W.; Werner, D.; Seelig, F.

2014-01-01

In the past decade, two pathogens transmitted by Culicoides biting midges (Diptera: Ceratopogonidae), bluetongue virus and Schmallenberg virus, have caused serious economic losses to the European livestock industry, most notably affecting sheep and cattle. These outbreaks of arboviral disease have

Bluetongue, Schmallenberg - what is next? : Culicoides-borne viral diseases in the 21st Century

NARCIS (Netherlands)

Koenraadt, Constantianus Jm; Balenghien, Thomas; Carpenter, Simon; Ducheyne, Els; Elbers, Armin Rw; Fife, Mark; Garros, Claire; Ibáñez-Justicia, Adolfo; Kampen, Helge; Kormelink, Richard Jm; Losson, Bertrand; van der Poel, Wim Hm; De Regge, Nick; van Rijn, Piet A; Sanders, Christopher; Schaffner, Francis; Sloet van Oldruitenborgh-Oosterbaan, Marianne M|info:eu-repo/dai/nl/075234394; Takken, Willem; Werner, Doreen; Seelig, Frederik

2014-01-01

In the past decade, two pathogens transmitted by Culicoides biting midges (Diptera: Ceratopogonidae), bluetongue virus and Schmallenberg virus, have caused serious economic losses to the European livestock industry, most notably affecting sheep and cattle. These outbreaks of arboviral disease have

Handling small arbovirus vectors safely during biosafety level 3 containment: Culicoides variipennis sonorensis (Diptera:Ceratopogonidae) and exotic bluetongue viruses.

Science.gov (United States)

Hunt, G J; Tabachnick, W J

1996-05-01

Equipment and procedures are described for biosafety level 3 (BL-3) containment work with small, zoophilic arthropods. BL-3 classified pathogens always must be manipulated in biological safety cabinets. Procedures, including physical barriers and handling methods, that prevent the escape of potentially virus-infected insects are discussed, and the use of a monitoring system for insect security is explained. The inability to recover escaped minute, flying insects poses a major difference from similar work with larger insects, such as mosquitoes. Methods were developed for the safe and secure handling of Culicoides variipennis sonorensis Wirth & Jones infected with exotic bluetongue viruses during BL-3 containment.

Molecular detection of Bluetongue Virus (BTV and Bovine Leukemia Virus (BLV in uterine biopsies of dairy cows with or without reproductive problems

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Juliana Marques Bicalho

2016-10-01

Full Text Available Reproductive performance of dairy cows has a direct impact on herd productivity. Infectious agents, such as Bluetongue Virus (BTV and Bovine Leukemia Virus (BLV, are associated with reproductive failure. However, it remains unknown if these viruses are present in the uterus and cause gestational loss. This study used molecular methods to assess if BTV and BLV can be detected in the uterus of serologically positive dairy cows with a record of abortions, stillbirths and repeat breeding (n=23 and without a record of reproductive problems (n =23. The cows came from three dairy herds of the state of Minas Gerais, Brazil. BTV was not detected in any of the uterine biopsies. Proviral DNA of BLV was detected in 54.5 % of the seropositive cows, but positivity for BLV in the uterus was not associated with the existence of reproductive problems. In conclusion, this study shows that BLV, but not BTV, is present in the uterus of seropositive cows, regardless of reproductive performance.

Detection in and circulation of Bluetongue virus among domestic ruminants in Madagascar.

Science.gov (United States)

Andriamandimby, Soa Fy; Viarouge, Cyril; Ravalohery, Jean-Pierre; Reynes, Jean-Marc; Sailleau, Corinne; Tantely, Michael Luciano; Elissa, Nohal; Cardinale, Eric; Sall, Amadou Alpha; Zientara, Stephan; Heraud, Jean-Michel

2015-04-17

So far, no published data was available concerning the circulation of Bluetongue virus (BTV) in Madagascar. During a survey on Rift Valley Fever, we were able to detect a virus belonging to BTV. Therefore, we conducted a study aiming at characterizing molecularly the BTV isolated and assess the importance of circulation of BTV in Madagascar. A total of 4393 sera from ruminants selected randomly by stratification and sampled in 30 districts of Madagascar were tested for BTV. Moreover, 175 cattle were followed during 11 months. Phylogenetic analyses were performed from virus isolated from unfed pools of mosquitoes. Overall, the estimated mean seroprevalence of infection at the national level was 95.9% (95% CI: [95.2-96.5]) in cattle and 83.7% (95% CI: [81.4-85.9]) in small ruminants. Estimation of incidence rate was 54 per 100 cattle-years assuming that the incidence rate is constant all year along. Phylogenetic analyses revealed that BTV detected belong to serotype 2. In conclusion, our results showed that BTV is endemic in Madagascar and highly prevalent among cattle. In our study we did not work on the vector involved in transmission of BTV in cattle. Thus, research should be conducted to better describe epidemiology of BTV in Madagascar including vectors and assess economic impact of the disease associated to BTV infections. Copyright © 2015 Elsevier B.V. All rights reserved.

Structural constraints in the packaging of bluetongue virus genomic segments.

Science.gov (United States)

Burkhardt, Christiane; Sung, Po-Yu; Celma, Cristina C; Roy, Polly

2014-10-01

The mechanism used by bluetongue virus (BTV) to ensure the sorting and packaging of its 10 genomic segments is still poorly understood. In this study, we investigated the packaging constraints for two BTV genomic segments from two different serotypes. Segment 4 (S4) of BTV serotype 9 was mutated sequentially and packaging of mutant ssRNAs was investigated by two newly developed RNA packaging assay systems, one in vivo and the other in vitro. Modelling of the mutated ssRNA followed by biochemical data analysis suggested that a conformational motif formed by interaction of the 5' and 3' ends of the molecule was necessary and sufficient for packaging. A similar structural signal was also identified in S8 of BTV serotype 1. Furthermore, the same conformational analysis of secondary structures for positive-sense ssRNAs was used to generate a chimeric segment that maintained the putative packaging motif but contained unrelated internal sequences. This chimeric segment was packaged successfully, confirming that the motif identified directs the correct packaging of the segment. © 2014 The Authors.

An investigation into the possibility of bluetongue virus transmission by transfer of infected ovine embryos

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Estelle H. Venter

2011-02-01

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.

Climate change and the spread of vector-borne diseases: using approximate Bayesian computation to compare invasion scenarios for the bluetongue virus vector Culicoides imicola in Italy

NARCIS (Netherlands)

Mardulyn, P.; Goffredo, M.; Conte, A.; Hendrickx, G.; Meiswinkel, R.; Balenghien, T.; Sghaier, S.; Lohr, Y.; Gilbert, M.

2013-01-01

Bluetongue (BT) is a commonly cited example of a disease with a distribution believed to have recently expanded in response to global warming. The BT virus is transmitted to ruminants by biting midges of the genus Culicoides, and it has been hypothesized that the emergence of BT in Mediterranean

VP7: an attachment protein of bluetongue virus for cellular receptors in Culicoides variipennis.

Science.gov (United States)

Xu, G; Wilson, W; Mecham, J; Murphy, K; Zhou, E M; Tabachnick, W

1997-07-01

The importance of VP7 of bluetongue virus (BTV) in the binding of BTV to membrane proteins of the BTV vector Culicoides variipennis was investigated. Core BTV particles, prepared from whole viruses, lacked outer proteins VP2 and VP5 and had VP7 exposed. More core particles and whole viruses bound to membrane preparations of adults of C. variipennis and KC cells, which were cultured from this vector insect, than to membrane preparations of Manduca sexta larvae. More core particles than whole viruses bound to membrane preparations of adults of C. variipennis and KC cells. Polyclonal anti-idiotypic antibodies (anti-Id), which were made against an antigen-combining region of an anti-BTV-10 VP7 antibody and functionally mimicked VP7, bound more to the membrane preparations of adults of C. variipennis and KC cells, and less to cytosol preparations. In Western overalay analysis, the Culicoides plasma membrane preparation reduced binding of an anti-VP7 monoclonal antibody to VP7. Whole and core BTV particles and the anti-Id bound to a membrane protein with a molecular mass of 23 kDa that was present predominantly in membrane preparations of adults of C. variipennis and KC cells. This protein was present in much lower concentrations in membrane preparations of C6/36 and DM-2 insect cells.

Evidence for transmission of bluetongue virus serotype 26 through direct contact.

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Carrie Batten

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.

Transmission and epidemiology of bluetongue and epizootic hemorrhagic disease in North America: current perspectives, research gaps, and future directions

Science.gov (United States)

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...

Detection of bluetongue virus in the blood of inoculated calves: comparison of virus isolation, PCR assay, and in vitro feeding of Culicoides variipennis.

Science.gov (United States)

MacLachlan, N J; Nunamaker, R A; Katz, J B; Sawyer, M M; Akita, G Y; Osburn, B I; Tabachnick, W J

1994-01-01

The interval after infection when bluetongue virus (BTV) was present in the blood of calves inoculated with BTV serotype 10 (BTV 10) was evaluated by virus isolation (VI) in embryonated chicken eggs (ECE), BTV-specific polymerase chain reaction (PCR), and in vitro blood feeding of vector Culicoides variipennis (C.v.) sonorensis. BTV nucleic acid was detected by PCR in blood cells for 16 to 20 weeks after infection whereas infectious virus was detected by VI in ECE for 2 to 8 weeks. BTV was detected in calf blood by in vitro feeding of C.v. sonorensis for only 0 to 2 weeks after inoculation of calves with BTV 10. Selected bloods which were positive by PCR analysis but not by VI in ECE were not infectious for sheep. The data are consistent with the hypothesis that prolonged viremia in BTV-infected cattle results from association of the virus with blood cells, especially erythrocytes. The fact that calf blood that contained viral nucleic acid as determined by PCR analysis, but not infectious virus as determined by VI in ECE, was not infectious for either the insect vector or sheep suggests that cattle whose blood contains BTV nucleic acid but not infectious virus are unimportant to the epidemiology of BTV infection.

Seroprevalence and Risk Factors of Bluetongue Virus Infection in Tibetan Sheep and Yaks in Tibetan Plateau, China.

Science.gov (United States)

Ma, Jian-Gang; Zhang, Xiao-Xuan; Zheng, Wen-Bin; Xu, Ying-Tian; Zhu, Xing-Quan; Hu, Gui-Xue; Zhou, Dong-Hui

2017-01-01

Bluetongue (BT), caused by bluetongue virus (BTV), is an arthropod-borne viral disease in ruminants. However, information about BTV infection in yaks in China is limited. Moreover, no such data concerning BTV in Tibetan sheep is available. Therefore, 3771 serum samples were collected from 2187 Tibetan sheep and 1584 yaks between April 2013 and March 2014 from Tibetan Plateau, western China, and tested for BTV antibodies using a commercially available ELISA kit. The overall seroprevalence of BTV was 17.34% (654/3771), with 20.3% (443/2187) in Tibetan sheep and 13.3% (211/1584) in yaks. In the Tibetan sheep group, the seroprevalence of BTV in Luqu, Maqu, Tianzhu, and Nyingchi Prefecture was 20.3%, 20.8%, 20.5%, and 19.1%, respectively. The seroprevalence of BTV in different season groups varied from 16.5% to 23.4%. In the yak group, BTV seroprevalence was 12.6%, 15.5%, and 11.0% in Tianzhu, Maqu, and Luqu counties, respectively. The seroprevalence in different seasons was 12.6%, 15.5%, 15.4%, and 9.0% in spring, summer, autumn, and winter, respectively. The season was the major risk factor concerning BTV infection in yaks ( P Tibetan sheep and yaks provides baseline information for controlling BT in ruminants in western China.

Identification and differentiation of the twenty six bluetongue virus serotypes by RT-PCR amplification of the serotype-specific genome segment 2.

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Narender S Maan

Full Text Available Bluetongue (BT is an arthropod-borne viral disease, which primarily affects ruminants in tropical and temperate regions of the world. Twenty six bluetongue virus (BTV serotypes have been recognised worldwide, including nine from Europe and fifteen in the United States. Identification of BTV serotype is important for vaccination programmes and for BTV epidemiology studies. Traditional typing methods (virus isolation and serum or virus neutralisation tests (SNT or VNT are slow (taking weeks, depend on availability of reference virus-strains or antisera and can be inconclusive. Nucleotide sequence analyses and phylogenetic comparisons of genome segment 2 (Seg-2 encoding BTV outer-capsid protein VP2 (the primary determinant of virus serotype were completed for reference strains of BTV-1 to 26, as well as multiple additional isolates from different geographic and temporal origins. The resulting Seg-2 database has been used to develop rapid (within 24 h and reliable RT-PCR-based typing assays for each BTV type. Multiple primer-pairs (at least three designed for each serotype were widely tested, providing an initial identification of serotype by amplification of a cDNA product of the expected size. Serotype was confirmed by sequencing of the cDNA amplicons and phylogenetic comparisons to previously characterised reference strains. The results from RT-PCR and sequencing were in perfect agreement with VNT for reference strains of all 26 BTV serotypes, as well as the field isolates tested. The serotype-specific primers showed no cross-amplification with reference strains of the remaining 25 serotypes, or multiple other isolates of the more closely related heterologous BTV types. The primers and RT-PCR assays developed in this study provide a rapid, sensitive and reliable method for the identification and differentiation of the twenty-six BTV serotypes, and will be updated periodically to maintain their relevance to current BTV distribution and

Disa vaccines for Bluetongue: A novel vaccine approach for insect-borne diseases

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Bluetongue virus (BTV) lacking functional NS3/NS3a protein is named Disabled Infectious Single Animal (DISA) vaccine. The BT DISA vaccine platform is broadly applied by exchange of serotype specific proteins. BT DISA vaccines are produced in standard cell lines in established production facilities, ...

The NS3 proteins of global strains of bluetongue virus evolve into regional topotypes through negative (purifying) selection.

Science.gov (United States)

Balasuriya, U B R; Nadler, S A; Wilson, W C; Pritchard, L I; Smythe, A B; Savini, G; Monaco, F; De Santis, P; Zhang, N; Tabachnick, W J; Maclachlan, N J

2008-01-01

Comparison of the deduced amino acid sequences of the genes (S10) encoding the NS3 protein of 137 strains of bluetongue virus (BTV) from Africa, the Americas, Asia, Australia and the Mediterranean Basin showed limited variation. Common to all NS3 sequences were potential glycosylation sites at amino acid residues 63 and 150 and a cysteine at residue 137, whereas a cysteine at residue 181 was not conserved. The PPXY and PS/TAP late-domain motifs were conserved in all but three of the viruses. Phylogenetic analyses of these same sequences yielded two principal clades that grouped the viruses irrespective of their serotype or year of isolation (1900-2003). All viruses from Asia and Australia were grouped in one clade, whereas those from the other regions were present in both clades. Each clade segregated into distinct subclades that included viruses from single or multiple regions, and the S10 genes of some field viruses were identical to those of live-attenuated BTV vaccines. There was no evidence of positive selection on the S10 gene as assessed by reconstruction of ancestral codon states on the phylogeny, rather the functional constraints of the NS3 protein are expressed through substantial negative (purifying) selection.

Multiserotype protection elicited by a combinatorial prime-boost vaccination strategy against bluetongue virus.

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Eva Calvo-Pinilla

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.

Microgeographic and temporal genetic variation in populations of the bluetongue virus vector Culicoides variipennis (Diptera: Ceratopogonidae).

Science.gov (United States)

Tabachnick, W J

1992-05-01

Seven Colorado populations of the bluetongue virus vector Culicoides varipennis (Coquillett) were analyzed for genetic variation at 19-21 isozyme loci. Permanent populations, which overwinter as larvae, showed little temporal genetic change at 19 loci. PGD and MDH showed seasonal changes in gene frequencies, attributable to selection at two permanent populations. Two temporary populations showed low heterozygosity compared with permanent populations. Independent estimates of gene flow, calculated using FST and the private allele method, were Nm* = 2.15 and 6.95, respectively. Colorado C. variipennis permanent populations showed high levels of gene flow which prevented significant genetic differentiation due to genetic drift. Temporary populations showed significant gene frequency differences from nearby permanent populations due to the "founder effect" associated with chance colonization.

The role of wildlife in bluetongue virus maintenance in Europe: lessons learned after the natural infection in Spain.

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Ruiz-Fons, Francisco; Sánchez-Matamoros, Almudena; Gortázar, Christian; Sánchez-Vizcaíno, José Manuel

2014-03-01

Bluetongue (BT) is a re-emergent vector-borne viral disease of domestic and wild ruminants caused by bluetongue virus (BTV), a member of the genus Orbivirus. A complex multi-host, multi-vector and multi-pathogen (26 serotypes) transmission and maintenance network has recently emerged in Europe, and wild ruminants are regarded as an important node in this network. This review analyses the reservoir role of wild ruminants in Europe, identifying gaps in knowledge and proposing actions. Wild ruminant species are indicators of BTV circulation. Excepting the mouflon (Ovis aries musimon), European wild ungulates do not develop clinical disease. Diagnostic techniques used in wildlife do not differ from those used in domestic ruminants provided they are validated. Demographic, behavioural and physiological traits of wild hosts modulate their relationship with BTV vectors and with the virus itself. While BTV has been eradicated from central and northern Europe, it is still circulating in the Mediterranean Basin. We propose that currently two BTV cycles coexist in certain regions of the Mediterranean Basin, a wild one largely driven by deer of the subfamily Cervinae and a domestic one. These are probably linked through shared Culicoides vectors of several species. We suggest that wildlife might be contributing to this situation through vector maintenance and virus maintenance. Additionally, differences in temperature and other environmental factors add complexity to the Mediterranean habitats as compared to central and northern European ones. Intervention options in wildlife populations are limited. There is a need to know the role of wildlife in maintaining Culicoides populations, and to know which Culicoides species mediate the wildlife-livestock-BTV transmission events. There is also a clear need to study more in depth the links between Cervinae deer densities, environmental factors and BTV maintenance. Regarding disease control, we suggest that research efforts should be

Seroprevalence of Bluetongue Virus in small ruminants in Balochistan province, Pakistan.

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Sohail, T; Yaqub, T; Shafee, M; Abbas, T; Nazir, J; Ullah, N; Rabbani, M; Chaudhary, M H; Mukhtar, N; Habib, M; Ul Rahman, A; Malik, A I; Ghafoor, A; Zahoor, M Y; Shabbir, M Z

2018-03-31

Bluetongue (BT), caused by bluetongue virus (BTV), is a vector-borne disease of small ruminants that has the potential to spread across international borders. Despite large populations of susceptible animals and borders with BTV endemic countries, little is known of the disease burden and prevalent serotypes in the province of Balochistan in Pakistan. We conducted a cross-sectional study to determine seroconversion and prevalent serotypes in selected districts of the province using a competitive enzyme-linked immunosorbent assay (cELISA) and real-time polymerase chain reaction (RT-PCR). Sera (n = 876) were collected from clinically healthy sheep and goats originating from the districts of Quetta (n = 300), Mastung (n = 201), Killa Saifullah (n = 75) and Kech (n = 300). None of the study herds (n = 97) were seronegative for BTV, and at the individual level, the overall prevalence of BTV seroconversion was 47.26% (n = 414/876, 95% CI = 43.92%-50.63%). A higher percentage of goats (50.87%, 95% CI = 45.99%-55.73%) were seropositive for anti-VP7 immunoglobulins (IgG) than sheep (44.21%, 95% CI = 39.81%-48.70%). Odds ratios of seroconversion for goats were associated with breed type (χ 2  = 16.84, p = .01), parity (χ 2  = 23.66, p = .00) and presence of vector (χ 2  = 2.63, p = .10), whereas for sheep, it was associated with breed type (χ 2  = 13.80, p = .01) and parity (χ 2  = 53.40, p = .00). Serotype 8 was the most prevalent (26.82%, 95% CI = 14.75%-43.21%) followed by an equal prevalence of serotypes 2 and 9 (7.31%, 95% CI = 1.91%-21.01%). To the best of our knowledge, this is the first study conducted in Balochistan province and the results indicate that there is a necessity to initiate intervention strategies to control BT disease burden not only in this region of Pakistan but also in adjacent areas of the neighbouring countries, Iran and Afghanistan. © 2018 Blackwell Verlag GmbH.

Humoral response to 2 inactivated bluetongue virus serotype-8 vaccines in South American camelids.

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Zanolari, P; Bruckner, L; Fricker, R; Kaufmann, C; Mudry, M; Griot, C; Meylan, M

2010-01-01

Bluetongue virus serotype 8 (BTV-8) has caused disease in domestic ruminants in several countries of northern Europe since 2006. In 2008 a mass-vaccination program was launched in most affected countries using whole virus inactivated vaccines. To evaluate 2 inactivated vaccines (Bovilis BTV 8; BTVPUR AlSap8) for immunogenicity and safety against BTV-8 in South American camelids (SAC) in a field trial. Forty-two SAC (25 Alpacas, 17 Llamas) aged between 1 and 16 years. The animals were vaccinated twice at intervals of 21 days. They were observed clinically for adverse local, systemic, or both reactions throughout the trial. Blood samples collected on days 0, 14, 21, 43, and 156 after vaccination were tested for the presence of BTV-8 virus by real time-polymerase chain reaction and of specific antibodies by competitive ELISA and a serum neutralization test. All vaccinated animals developed antibodies to BTV-8 after the 2nd administration of the vaccine. No adverse effects were observed except for moderate local swellings at the injection site, which disappeared within 21 days. Slightly increased body temperatures were only observed in the first 2 days after vaccination. The BTV was not detected in any of the samples analyzed. The administration of the 2 inactivated commercial vaccines was safe and induced seroconversion against BTV-8 in all vaccinated animals. The results of this study suggest that 2 doses injected 3 weeks apart is a suitable vaccination regimen for SAC.

Simulating spread of Bluetongue Virus by flying vectors between hosts on pasture

DEFF Research Database (Denmark)

Græsbøll, Kaare; Bødker, Rene; Enøe, Claes

2012-01-01

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 freely...

Bluetongue disease and seroprevalence in South American camelids from the northwestern region of the United States.

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Allen, Andrew J; Stanton, James B; Evermann, James F; Fry, Lindsay M; Ackerman, Melissa G; Barrington, George M

2015-03-01

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. © 2015 The Author(s).

Prevalência de anticorpos contra o vírus da língua azul em bovinos e ovinos do Sudoeste e Sudeste do Rio Grande do Sul Bluetongue virus antibodies in cattle and sheep in Southwest and Southeast regions of Rio Grande do Sul, Brazil

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J.R.R. Costa

2006-04-01

Full Text Available It was studied bluetongue virus antibodies prevalence for sheep and cattle in Southwest and Southeast regions of Rio Grande do Sul State. A total of 2613 serum samples (1272 bovine and 1341 ovine were tested by agar gel immunodiffusion. Eight bovine and two ovine samples were positive meaning a prevalence of 0.63% and 0.15%, respectively. These results show that most of animals in these regions are negative to bluetongue.

Identification of a salivary vasodilator in the primary North American vector of bluetongue viruses, Culicoides variipennis.

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Perez de Leon, A A; Ribeiro, J M; Tabachnick, W J; Valenzuela, J G

1997-09-01

Several species of Culicoides biting midges are important pests and vectors of pathogens affecting humans and other animals. Bluetongue is the most economically important arthropod-borne animal disease in the United States. Culicoides variipennis is the primary North American vector of the bluetongue viruses. A reddish halo surrounding a petechial hemorrhage was noticed at the site of C. variipennis blood feeding in previously unexposed sheep and rabbits. Salivary gland extracts of nonblood-fed C. variipennis injected intradermally into sheep and rabbits induced cutaneous vasodilation in the form of erythema. A local, dose-dependent erythema, without edema or pruritus, was noted 30 min after injection. Erythema was inapparent with salivary gland extracts obtained after blood feeding. This observation suggested that the vasodilatory activity was inoculated into the host skin at the feeding site. The vasodilatory activity was insoluble in ethanol and destroyed by trypsin or chymotrypsin, which indicated that vasodilation was due to a protein. The association of cutaneous vasodilation with a salivary protein was corroborated by reversed-phase, high-performance liquid chromatography (HPLC). Fractionation of salivary gland extracts by molecular sieving HPLC resulted in maximal vasodilatory activity that coeluted with a protein having a relative molecular weight (MWr) of 22.45 kD. The C. variipennis vasodilator appears to be biologically active at the nanogram level. This vasodilator likely assists C. variipennis during feeding by increasing blood flow from host superficial blood vessels surrounding the bite site. The identification of a salivary vasodilator in C. variipennis may have implications for the transmission of Culicoides-borne pathogens and in the development of dermatitis resulting from the sensitization of humans and animals to Culicoides salivary antigens.

Vector competence of Culicoides bolitinos and C. imicola for South African bluetongue virus serotypes 1, 3 and 4.

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Venter, G J; Paweska, J T; Van Dijk, A A; Mellor, P S; Tabachnick, W J

1998-10-01

The susceptibility of field-collected Culicoides bolitinos to infection by oral ingestion of bluetongue virus serotypes 1, 3 and 4 (BLU 1, 3 and 4) was compared with that of field-collected C. imicola and laboratory reared C. variipennis sonorensis. The concentration of the virus per millilitre of bloodmeal was 10(5.0) and 10(6.0)TCID50 for BLU 4 and 10(7.2)TCID50 for BLU 1 and 3. Of 4927 C. bolitinos and 9585 C. imicola fed, 386 and 287 individual midges survived 10 days extrinsic incubation, respectively. Midges were assayed for the presence of virus using a microtitration assay on BHK-21 cells and/or an antigen capture ELISA. Infection prevalences for the different serotypes as determined by virus isolation ranged from 22.7 to 82.0% in C. bolitinos and from 1.9 to 9.8% in C. imicola; infection prevalences were highest for BLU 1, and lowest for BLU 4 in both species. The mean log10 TCID50 titre of the three BLU viruses per single fly was higher in C. bolitinos than in C. imicola. The results suggested that C. bolitinos populations are capable vectors of the BLU viruses in South Africa. A high correlation was found between virus isolation and ELISA results for the detection of BLU 1, and less for BLU 4; the ELISA failed to detect the presence of BLU 3 in infected flies. The C. v. sonorensis colonies had a significantly lower susceptibility to infection with BLU 1, 3 and 4 than C. bolitinos and C. imicola. However, since infection prevalence of C. v. sonorensis was determined only by ELISA, this finding may merely reflect the insensitivity of this assay at low virus titres, compared to virus isolation.

Possible over-wintering of bluetongue virus in Culicoides populations in the Onderstepoort area, Gauteng, South Africa

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Jumari Steyn

2016-10-01

Full Text Available Several studies have demonstrated the ability of certain viruses to overwinter in arthropod vectors. The over-wintering mechanism of bluetongue virus (BTV is unknown. One hypothesis is over-wintering within adult Culicoides midges (Diptera; Ceratopogonidae that survive mild winters where temperatures seldom drop below 10 °C. The reduced activity of midges and the absence of outbreaks during winter may create the impression that the virus has disappeared from an area. Light traps were used in close association with horses to collect Culicoides midges from July 2010 to September 2011 in the Onderstepoort area, in Gauteng Province, South Africa. More than 500 000 Culicoides midges were collected from 88 collections and sorted to species level, revealing 26 different Culicoides species. Culicoides midges were present throughout the 15 month study. Nine Culicoides species potentially capable of transmitting BTV were present during the winter months. Midges were screened for the presence of BTV ribonucleic acid (RNA with the aid of a real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR assay. In total 91.2% of midge pools tested positive for BTV RNA. PCR results were compared with previous virus isolation results (VI that demonstrated the presence of viruses in summer and autumn months. The results indicate that BTV-infected Culicoides vectors are present throughout the year in the study area. Viral RNA-positive midges were also found throughout the year with VI positive midge pools only in summer and early autumn. Midges that survive mild winter temperatures could therefore harbour BTV but with a decreased vector capacity. When the population size, biting rate and viral replication decrease, it could stop BTV transmission. Over-wintering of BTV in the Onderstepoort region could therefore result in re-emergence because of increased vector activity rather than reintroduction from outside the region.

Aanzet tot een risk analysis m.b.t. introductie van bluetongue virus en West Nile virus in Nederland

NARCIS (Netherlands)

Elbers, A.R.W.; Rijn, van P.A.; Rooij, van E.M.A.

2003-01-01

Door het CIDC-Lelystad is een risicoanalyse m.b.t. de mogelijke introductie in Nederland opgesteld. De conclusie was dat er een zeker risico is voor introductie van bluetongue in Nederland. De introductie kan het gevolg zijn van steeds uitgebreidere verspreiding van geïnfecteerde insecten, maar ook

Prevalence of bluetongue virus antibodies and associated risk factors among cattle in East Darfur State, Western Sudan.

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Khair, Hadia Om; Adam, Ibrahim A; Bushara, Shakir B; Eltom, Kamal H; Musa, Nasreen O; Aradaib, Imadeldin E

2014-02-07

Bluetongue virus (BTV) is an insect-transmitted virus, which causes bluetongue disease (BT) in sheep and a fatal hemorrhagic infection in North American white-tailed deer. However, in cattle the disease is typically asymptomatic and no overt clinical signs of disease appear to be associated with BTV infection. Serological evidence and isolation of different BTV serotypes have been reported in Sudan, however, no information is currently available in regard to previous exposure of Sudanese livestock to BTV infection in East Darfur State, Sudan. To determine the prevalence of BTV antibodies and to identify the potential risk factors associated with BTV infection among cattle in East Darfur State, Sudan. A total of 224 blood samples were collected randomly from five localities in East Darfur State, Sudan. The serum samples were screened for detection of BTV-specific immunoglobulin G (IgG) antibodies using a competitive enzyme-linked immunosorbent assay (c-ELISA). Serological evidence of BTV infection was observed in 150 out of 224 animals accounting for a 67% prevalence rate among cattle in East Darfur State. Older cattle (>2 years of age) were six times more likely to be infected with BTV (OR = 6.62, CI = 2.87-15.26, p-value = 0.01). Regarding animal source (contact with other herds) as a risk factor, it was shown that cattle purchased from market or introduced from other herds were 3 times at higher risk of being infected with BTV (OR = 3.87, CI = 1.07-13.87, p value = 0.03). Exposure of cattle to the insect vector increased the risk of contracting BTV infection by six times compared to non-exposed cattle (OR = 6.44, CI = 1.53-27.08, p value = 0.01). The present study indicated that age, animal source and the intensity of the insect vector are influential risk factors for BTV infection in cattle in the Darfur region. Surveillance for BTV infection should be extended to include other susceptible ruminants and to study the distribution of the insect vectors to better

Occurrence of Bluetongue in ruminants in Tamil Nadu, South India.

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Reddy, Y Krishnamohan; Brindha, K; Ganesan, P I; Srinivas, K; Reddy, G S; Minakshi, P

2016-09-30

Tamil Nadu is located in the South-Eastern part of Indian peninsula, between 8.087° and 13.09°N and 76.50° and 80.27°E. Bluetongue (BT) was first reported in this region in sheep during 1982 with regular occurrence thereafter. In 1989-1990, 1997-1998 and 2005-2006, there was wide spread occurrence of BT resulting in huge mortality of sheep. The present study had the goal of isolating the BTV from outbreaks in sheep occurred in Tamil Naadu between 2003-2011 and comparing the VP2 gene sequences of the BTV isolates involved in such outbreaks. Serotypes 1, 2, 16, and 23 of the Bluetongue virus (BTV) have been isolated from sheep during BT outbreaks. BTV-16 has also been isolated in goats and cattle in the region; BTV-2 isolated in Tamil Nadu has homology with BTV-2 isolated in Africa; whereas the BTV-23 isolated in this area has homology with BTV-23 from South East Asia, indicating that both Eastern and Western topotypes of BTV are circulating in ruminant population in Tamil Nadu.

Bluetongue virus non-structural protein 1 is a positive regulator of viral protein synthesis

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Boyce Mark

2012-08-01

Full Text Available Abstract Background Bluetongue virus (BTV is a double-stranded RNA (dsRNA virus of the Reoviridae family, which encodes its genes in ten linear dsRNA segments. BTV mRNAs are synthesised by the viral RNA-dependent RNA polymerase (RdRp as exact plus sense copies of the genome segments. Infection of mammalian cells with BTV rapidly replaces cellular protein synthesis with viral protein synthesis, but the regulation of viral gene expression in the Orbivirus genus has not been investigated. Results Using an mRNA reporter system based on genome segment 10 of BTV fused with GFP we identify the protein characteristic of this genus, non-structural protein 1 (NS1 as sufficient to upregulate translation. The wider applicability of this phenomenon among the viral genes is demonstrated using the untranslated regions (UTRs of BTV genome segments flanking the quantifiable Renilla luciferase ORF in chimeric mRNAs. The UTRs of viral mRNAs are shown to be determinants of the amount of protein synthesised, with the pre-expression of NS1 increasing the quantity in each case. The increased expression induced by pre-expression of NS1 is confirmed in virus infected cells by generating a replicating virus which expresses the reporter fused with genome segment 10, using reverse genetics. Moreover, NS1-mediated upregulation of expression is restricted to mRNAs which lack the cellular 3′ poly(A sequence identifying the 3′ end as a necessary determinant in specifically increasing the translation of viral mRNA in the presence of cellular mRNA. Conclusions NS1 is identified as a positive regulator of viral protein synthesis. We propose a model of translational regulation where NS1 upregulates the synthesis of viral proteins, including itself, and creates a positive feedback loop of NS1 expression, which rapidly increases the expression of all the viral proteins. The efficient translation of viral reporter mRNAs among cellular mRNAs can account for the observed

Bluetongue virus non-structural protein 1 is a positive regulator of viral protein synthesis.

Science.gov (United States)

Boyce, Mark; Celma, Cristina C P; Roy, Polly

2012-08-29

Bluetongue virus (BTV) is a double-stranded RNA (dsRNA) virus of the Reoviridae family, which encodes its genes in ten linear dsRNA segments. BTV mRNAs are synthesised by the viral RNA-dependent RNA polymerase (RdRp) as exact plus sense copies of the genome segments. Infection of mammalian cells with BTV rapidly replaces cellular protein synthesis with viral protein synthesis, but the regulation of viral gene expression in the Orbivirus genus has not been investigated. Using an mRNA reporter system based on genome segment 10 of BTV fused with GFP we identify the protein characteristic of this genus, non-structural protein 1 (NS1) as sufficient to upregulate translation. The wider applicability of this phenomenon among the viral genes is demonstrated using the untranslated regions (UTRs) of BTV genome segments flanking the quantifiable Renilla luciferase ORF in chimeric mRNAs. The UTRs of viral mRNAs are shown to be determinants of the amount of protein synthesised, with the pre-expression of NS1 increasing the quantity in each case. The increased expression induced by pre-expression of NS1 is confirmed in virus infected cells by generating a replicating virus which expresses the reporter fused with genome segment 10, using reverse genetics. Moreover, NS1-mediated upregulation of expression is restricted to mRNAs which lack the cellular 3' poly(A) sequence identifying the 3' end as a necessary determinant in specifically increasing the translation of viral mRNA in the presence of cellular mRNA. NS1 is identified as a positive regulator of viral protein synthesis. We propose a model of translational regulation where NS1 upregulates the synthesis of viral proteins, including itself, and creates a positive feedback loop of NS1 expression, which rapidly increases the expression of all the viral proteins. The efficient translation of viral reporter mRNAs among cellular mRNAs can account for the observed replacement of cellular protein synthesis with viral protein

Variation in Bluetongue virus real-time reverse transcription polymerase chain reaction assay results in blood samples of sheep, cattle, and alpaca.

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Brito, Barbara P; Gardner, Ian A; Hietala, Sharon K; Crossley, Beate M

2011-07-01

Bluetongue is a vector-borne viral disease that affects domestic and wild ruminants. The epidemiology of this disease has recently changed, with occurrence in new geographic areas. Various real-time quantitative reverse transcription polymerase chain reaction (real-time qRT-PCR) assays are used to detect Bluetongue virus (BTV); however, the impact of biologic differences between New World camelids and domestic ruminant samples on PCR efficiency, for which the BTV real-time qRT-PCR was initially validated are unknown. New world camelids are known to have important biologic differences in whole blood composition, including hemoglobin concentration, which can alter PCR performance. In the present study, sheep, cattle, and alpaca blood were spiked with BTV serotypes 10, 11, 13, and 17 and analyzed in 10-fold dilutions by real-time qRT-PCR to determine if species affected nucleic acid recovery and assay performance. A separate experiment was performed using spiked alpaca blood subsequently diluted in 10-fold series in sheep blood to assess the influence of alpaca blood on performance efficiency of the BTV real-time qRT-PCR assay. Results showed that BTV-specific nucleic acid detection from alpaca blood was consistently 1-2 logs lower than from sheep and cattle blood, and results were similar for each of the 4 BTV serotypes analyzed.

Analysis of bluetongue serotype 3 spread in Tunisia and discovery of a novel strain related to the bluetongue virus isolated from a commercial sheep pox vaccine.

Science.gov (United States)

Lorusso, Alessio; Sghaier, Soufien; Di Domenico, Marco; Barbria, Mohamed Elias; Zaccaria, Guendalina; Megdich, Aida; Portanti, Ottavio; Seliman, Imed Ben; Spedicato, Massimo; Pizzurro, Federica; Carmine, Irene; Teodori, Liana; Mahjoub, Mejdi; Mangone, Iolanda; Leone, Alessandra; Hammami, Salah; Marcacci, Maurilia; Savini, Giovanni

2018-04-01

Bluetongue (BT), is one of the OIE-listed major diseases of ruminants. Following the official report of BT virus serotype 3 (BTV-3) in a sheep in Cap Bon (Tunisia), blood and serum samples of ruminants were collected from some areas of Tunisia to further investigate the presence of this virus in the country. A quantitative real time RT-PCR has been first developed for the detection and quantitation of BTV-3 RNA from field specimens. Out of 62 collected blood samples, 23 were shown to be positive for BTV-3 RNA. Isolation on cell cultures was also possible from six samples. Genome sequencing revealed the circulation of two unrelated western strains of BTV-3, one circulating in Cap Bon and neighboring areas, and the other circulating nearby the border with Libya. The presence of a putative novel BTV serotype (BTV-Y TUN2017) in sheep introduced from Libya to Tunisia, genomically related to the BTV strain contaminating a commercially-available sheep pox vaccine and to BTV-26, has been also demonstrated. This finding highlights the pressing need for a prompt production and release of a novel inactivated BTV-3 vaccine to be used in case of emergence or proactively in the areas of Southern Europe at major risk of BTV introduction. The assessment of a novel vaccine will certainly exalt the role and importance of surveillance activities and collaboration with Northern African countries. Copyright © 2018 Elsevier B.V. All rights reserved.

Seasonal and interseasonal dynamics of bluetongue virus infection of dairy cattle and Culicoides sonorensis midges in northern California--implications for virus overwintering in temperate zones.

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Christie E Mayo

Full Text Available Bluetongue virus (BTV is the cause of an economically important arboviral disease of domestic and wild ruminants. The occurrence of BTV infection of livestock is distinctly seasonal in temperate regions of the world, thus we determined the dynamics of BTV infection (using BTV-specific real time reverse transcriptase polymerase chain reaction among sentinel cattle and vector Culicoides sonorensis (C. sonorensis midges on a dairy farm in northern California throughout both the seasonal and interseasonal (overwintering periods of BTV activity from August 2012 until March 2014. The data confirmed widespread infection of both sentinel cattle and vector midges during the August-November period of seasonal BTV transmission, however BTV infection of parous female midges captured in traps set during daylight hours also was detected in February of both 2013 and 2014, during the interseasonal period. The finding of BTV-infected vector midges during mid-winter suggests that BTV may overwinter in northern California by infection of long-lived female C. sonorensis midges that were infected during the prior seasonal period of virus transmission, and reemerged sporadically during the overwintering period; however the data do not definitively preclude other potential mechanisms of BTV overwintering that are also discussed.

A survey of free-ranging deer in Ireland for serological evidence of exposure to bovine viral diarrhoea virus, bovine herpes virus-1, bluetongue virus and Schmallenberg virus.

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Graham, David A; Gallagher, Clare; Carden, Ruth F; Lozano, Jose-Maria; Moriarty, John; O'Neill, Ronan

2017-01-01

Deer are an important wildlife species in both the Republic of Ireland and Northern Ireland having colonised most regions across the island of Ireland. In comparison to cattle and sheep which represent the main farmed ruminant species on the island, there is a lack of data concerning their exposure, as measured by the presence of antibodies, to important viral pathogens of ruminants. A study was therefore undertaken to investigate the seroprevalence of wild deer to four viruses, namely bovine viral diarrhoea virus (BVDV), bovine herpesvirus-1 (BoHV-1), Schmallenberg virus (SBV) and bluetongue virus (BTV). Two panels of sera were assembled; Panel 1 comprised 259 samples (202 collected in the Republic of Ireland and 57 in Northern Ireland) between 2013 and 2015, while Panel 2 comprised 131 samples collected in the Republic of Ireland between 2014 and 2015. Overall sika deer ( Cervus nippon ) were sampled most commonly (54.8%), followed by fallow deer ( Dama dama ) (35.3%), with red deer ( Cervus elaphus ) (4.3%) and hybrid species (0.3%) sampled less frequently, with the species not being recorded for the remaining 5.3% of deer sampled. Age was not recorded for 96 of the 390 deer sampled. 196 of the remainder were adults, while 68 and 30 were yearlings and calves, respectively. Using commercially available enzyme-linked immunosorbent assays, true prevalence and 95% confidence intervals were calculated as 9.9%, (6.8-13.0% CI), SBV; 1.5% (0.1-3.0% CI), BoHV-1; 0.0%, 0-1.7% CI), BVDV; and 0.0%, (0.01-0.10% CI), BTV. The results indicate a very low seroprevalence for both BVDV and BoHV-1 in the wild deer tested within the study and, are consistent with a very low prevalence in Ireland. While serological cross-reaction with cervid herpesviruses cannot be excluded, the results in both cases suggest that the presence of these viruses in deer is not a significant risk to their control and eradication from the cattle population. This is important given the ongoing programme

Assessing the consequences of an incursion of a vector-borne disease. II. Spread of bluetongue in Scotland and impact of vaccination

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Camille Szmaragd

2010-09-01

Full Text Available Bluetongue is a viral disease of ruminants transmitted by Culicoides biting midges, which has spread across Europe over the past decade. The disease arrived in south-east England in 2007, raising the possibility that it could pose a risk to the valuable Scottish livestock industry. As part of an assessment of the economic consequences of a bluetongue virus incursion into Scotland commissioned by Scottish Government, we investigated a defined set of feasible incursion scenarios under different vaccination strategies. Our epidemiological simulations, based on expert knowledge, highlighted that infection will rarely spread in Scotland after the initial incursion and will be efficiently controlled by vaccination. Keywords: Epidemiology, modelling, disease control

Culicoides-virus interactions: infection barriers and possible factors underlying vector competence

Science.gov (United States)

In the United States, Culicoides midges vector arboviruses of economic importance such as Bluetongue Virus and Epizootic Hemorrhagic Disease Virus. A limited number of studies have demonstrated the complexities of midge-virus interactions, including dynamic changes in virus titer and prevalence over...

Preliminary bluetongue Transmission with the sheep ked Melophagus ovinus (L.).

Science.gov (United States)

Luedke, A J; Jochim, M M; Bowne, J G

1965-09-01

Five experiments indicated that the sheep ked MELOPHAGUS OVINUS (L.), can transmit bluetongue virus (BTV) in sheep. It was not determined whether these were mechanical or biological transmissions, although the results suggested mechanical transmission. Sheep keds were manually transferred from a BTV-host sheep to 18 susceptible test sheep. Of these, 10 were positive (5 with mild reactions), 6 questionable, and 2 negative for BTV. Three of the mildly reacting sheep and 3 of the questionable sheep had highly intensified reactions on challenge inoculation. Five of the positive sheep were immune on challenge inoculation. Blood from 2 positive reactors was subpassaged into susceptible sheep, which reacted with typical disease signs.

Structure based modification of Bluetongue virus helicase protein VP6 to produce a viable VP6-truncated BTV

Energy Technology Data Exchange (ETDEWEB)

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: polly.roy@lshtm.ac.uk [Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT (United Kingdom)

2014-09-05

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.

Environmental heterogeneity and variations in the velocity of bluetongue virus spread in six European epidemics.

Science.gov (United States)

Nicolas, Gaëlle; Tisseuil, Clément; Conte, Annamaria; Allepuz, Alberto; Pioz, Maryline; Lancelot, Renaud; Gilbert, Marius

2018-01-01

Several epidemics caused by different bluetongue virus (BTV) serotypes occurred in European ruminants since the early 2000. Studies on the spatial distribution of these vector-borne infections and the main vector species highlighted contrasted eco-climatic regions characterized by different dominant vector species. However, little work was done regarding the factors associated with the velocity of these epidemics. In this study, we aimed to quantify and compare the velocity of BTV epidemic that have affected different European countries under contrasted eco-climatic conditions and to relate these estimates to spatial factors such as temperature and host density. We used the thin plate spline regression interpolation method in combination with trend surface analysis to quantify the local velocity of different epidemics that have affected France (BTV-8 2007-2008, BTV-1 2008-2009), Italy (BTV-1 2014), Andalusia in Spain (BTV-1 2007) and the Balkans (BTV-4 2014). We found significant differences in the local velocity of BTV spread according to the country and epidemics, ranging from 7.9km/week (BTV-1 2014 Italy) to 24.4km/week (BTV-1 2008 France). We quantify and discuss the effect of temperature and local host density on this velocity. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Preliminary Bluetongue Transmissions with the Sheep Ked Melophagus Ovinus (L.)*

Science.gov (United States)

Luedke, A. J.; Jochim, M. M.; Bowne, J. G.

1965-01-01

Five experiments indicated that the sheep ked MELOPHAGUS OVINUS (L.), can transmit bluetongue virus (BTV) in sheep. It was not determined whether these were mechanical or biological transmissions, although the results suggested mechanical transmission. Sheep keds were manually transferred from a BTV-host sheep to 18 susceptible test sheep. Of these, 10 were positive (5 with mild reactions), 6 questionable, and 2 negative for BTV. Three of the mildly reacting sheep and 3 of the questionable sheep had highly intensified reactions on challenge inoculation. Five of the positive sheep were immune on challenge inoculation. Blood from 2 positive reactors was subpassaged into susceptible sheep, which reacted with typical disease signs. PMID:4221988

Antigenic evidence of bluetongue virus from small ruminant population of two different geographical regions of Odisha, India

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Shaswati Subhadarsini Pany

2016-03-01

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.

Genetic characterization of the non-structural protein-3 gene of bluetongue virus serotype-2 isolate from India

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Raghavendra Sumanth Pudupakam

2017-03-01

Full Text Available Aim: Sequence analysis and phylogenetic studies based on non-structural protein-3 (NS3 gene are important in understanding the evolution and epidemiology of bluetongue virus (BTV. This study was aimed at characterizing the NS3 gene sequence of Indian BTV serotype-2 (BTV2 to elucidate its genetic relationship to global BTV isolates. Materials and Methods: The NS3 gene of BTV2 was amplified from infected BHK-21 cell cultures, cloned and subjected to sequence analysis. The generated NS3 gene sequence was compared with the corresponding sequences of different BTV serotypes across the world, and a phylogenetic relationship was established. Results: The NS3 gene of BTV2 showed moderate levels of variability in comparison to different BTV serotypes, with nucleotide sequence identities ranging from 81% to 98%. The region showed high sequence homology of 93-99% at amino acid level with various BTV serotypes. The PPXY/PTAP late domain motifs, glycosylation sites, hydrophobic domains, and the amino acid residues critical for virus-host interactions were conserved in NS3 protein. Phylogenetic analysis revealed that BTV isolates segregate into four topotypes and that the Indian BTV2 in subclade IA is closely related to Asian and Australian origin strains. Conclusion: Analysis of the NS3 gene indicated that Indian BTV2 isolate is closely related to strains from Asia and Australia, suggesting a common origin of infection. Although the pattern of evolution of BTV2 isolate is different from other global isolates, the deduced amino acid sequence of NS3 protein demonstrated high molecular stability.

Genetic characterization of the non-structural protein-3 gene of bluetongue virus serotype-2 isolate from India.

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Pudupakam, Raghavendra Sumanth; Raghunath, Shobana; Pudupakam, Meghanath; Daggupati, Sreenivasulu

2017-03-01

Sequence analysis and phylogenetic studies based on non-structural protein-3 (NS3) gene are important in understanding the evolution and epidemiology of bluetongue virus (BTV). This study was aimed at characterizing the NS3 gene sequence of Indian BTV serotype-2 (BTV2) to elucidate its genetic relationship to global BTV isolates. The NS3 gene of BTV2 was amplified from infected BHK-21 cell cultures, cloned and subjected to sequence analysis. The generated NS3 gene sequence was compared with the corresponding sequences of different BTV serotypes across the world, and a phylogenetic relationship was established. The NS3 gene of BTV2 showed moderate levels of variability in comparison to different BTV serotypes, with nucleotide sequence identities ranging from 81% to 98%. The region showed high sequence homology of 93-99% at amino acid level with various BTV serotypes. The PPXY/PTAP late domain motifs, glycosylation sites, hydrophobic domains, and the amino acid residues critical for virus-host interactions were conserved in NS3 protein. Phylogenetic analysis revealed that BTV isolates segregate into four topotypes and that the Indian BTV2 in subclade IA is closely related to Asian and Australian origin strains. Analysis of the NS3 gene indicated that Indian BTV2 isolate is closely related to strains from Asia and Australia, suggesting a common origin of infection. Although the pattern of evolution of BTV2 isolate is different from other global isolates, the deduced amino acid sequence of NS3 protein demonstrated high molecular stability.

Seroepidemiology of bluetongue in South Bengal

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Arkendu Halder

2016-01-01

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 Genome Characterisation of Bluetonge Virus Seroptype 6 from the Netherlands 2008 and Comparison to Other Field and Vaccine Strains

NARCIS (Netherlands)

Maan, S.; Maan, N.S.; Rijn, van P.A.; Gennip, van H.G.P.; Sanders, A.A.; Wright, I.M.; Batten, C.; Hoffmann, B.; Eschbaumer, M.; Oura, C.A.L.; Potgieter, C.; Nomikou, K.; Mertens, P.P.C.

2010-01-01

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)

Bluetongue Disabled Infectious Single Animal (DISA) vaccine: Studies on the optimal route and dose in sheep.

Science.gov (United States)

van Rijn, Piet A; Daus, Franz J; Maris-Veldhuis, Mieke A; Feenstra, Femke; van Gennip, René G P

2017-01-05

Bluetongue (BT) is a disease of ruminants caused by bluetongue virus (BTV) transmitted by biting midges of the Culicoides genus. Outbreaks have been controlled successfully by vaccination, however, currently available BT vaccines have several shortcomings. Recently, we have developed BT Disabled Infectious Single Animal (DISA) vaccines based on live-attenuated BTV without expression of dispensable non-structural NS3/NS3a protein. DISA vaccines are non-pathogenic replicating vaccines, do not cause viremia, enable DIVA and are highly protective. NS3/NS3a protein is involved in virus release, cytopathogenic effect and suppression of Interferon-I induction, suggesting that the vaccination route can be of importance. A standardized dose of DISA vaccine for serotype 8 has successfully been tested by subcutaneous vaccination. We show that 10 and 100times dilutions of this previously tested dose did not reduce the VP7 humoral response. Further, the vaccination route of DISA vaccine strongly determined the induction of VP7 directed antibodies (Abs). Intravenous vaccination induced high and prolonged humoral response but is not practical in field situations. VP7 seroconversion was stronger by intramuscular vaccination than by subcutaneous vaccination. For both vaccination routes and for two different DISA vaccine backbones, IgM Abs were rapidly induced but declined after 14days post vaccination (dpv), whereas the IgG response was slower. Interestingly, intramuscular vaccination resulted in an initial peak followed by a decline up to 21dpv and then increased again. This second increase is a steady and continuous increase of IgG Abs. These results indicate that intramuscular vaccination is the optimal route. The protective dose of DISA vaccine has not been determined yet, but it is expected to be significantly lower than of currently used BT vaccines. Therefore, in addition to the advantages of improved safety and DIVA compatibility, the novel DISA vaccines will be cost

Surveillance of bluetongue virus antibody in goats using a recombinant VP7-based indirect ELISA in the coastal saline area of West Bengal, India

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Raj K. Singh

2009-06-01

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.

Emerging vector-borne diseases in dromedaries in Tunisia: West Nile, bluetongue, epizootic haemorrhagic disease and Rift Valley fever

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Thameur B. Hassine

2017-03-01

Full Text Available A total of 118 sera were collected during 2016 from two groups of dromedaries from Kebili and Medenine governorates in the south of Tunisia. The aim of this study was to provide the first serological investigation of four emerging vector-borne diseases in two groups of dromedaries in Tunisia. Sera were tested by ELISA and serum neutralisation test to identify West Nile virus (WNV, bluetongue virus (BTV, epizootic haemorrhagic disease virus (EHDV and Rift Valley fever virus (RVFV. In the first group, the seroprevalence for BTV was 4.6%, while in the second group, it was 25.8% for WNV and 9.7% for BTV. Only serotype 1 was detected for BTV in the two groups. No evidence for circulation of RVF and EHD viruses was revealed. Results indicated that dromedaries can be infected with BTV and WNV, suggesting that this species might play a significant role in the epizootiology of these viral diseases in Tunisia and neighbouring countries.

Emerging vector-borne diseases in dromedaries in Tunisia: West Nile, bluetongue, epizootic haemorrhagic disease and Rift Valley fever.

Science.gov (United States)

Hassine, Thameur B; Amdouni, Jihane; Monaco, Federica; Savini, Giovanni; Sghaier, Soufien; Selimen, Imed B; Chandoul, Walid; Hamida, Khaled B; Hammami, Salah

2017-03-31

A total of 118 sera were collected during 2016 from two groups of dromedaries from Kebili and Medenine governorates in the south of Tunisia. The aim of this study was to provide the first serological investigation of four emerging vector-borne diseases in two groups of dromedaries in Tunisia. Sera were tested by ELISA and serum neutralisation test to identify West Nile virus (WNV), bluetongue virus (BTV), epizootic haemorrhagic disease virus (EHDV) and Rift Valley fever virus (RVFV). In the first group, the seroprevalence for BTV was 4.6%, while in the second group, it was 25.8% for WNV and 9.7% for BTV. Only serotype 1 was detected for BTV in the two groups. No evidence for circulation of RVF and EHD viruses was revealed. Results indicated that dromedaries can be infected with BTV and WNV, suggesting that this species might play a significant role in the epizootiology of these viral diseases in Tunisia and neighbouring countries.

Monitoring of biting midges (Diptera: Ceratopogonidae: Culicoides Latreille) on farms in Sweden during the emergence of the 2008 epidemic of bluetongue

DEFF Research Database (Denmark)

Nielsen, Søren Achim; Nielsen, Boy Overgaard; Chirico, Jan

2010-01-01

In light of the emergence of bluetongue in northern Europe, populations of Culicoides species were monitored in 2007-2008 by means of Onderstepoort blacklight suction traps operating at livestock farms in Sweden. The location of the 22 sampling sites ranged from about latitude 55°N to about 68°N....... A total of 61,669 male and female Culicoides were captured, of which, 52,319 were trapped outside the farms and 9,350 in byres or livestock sheds. Thirty-three Culicoides species were recorded, of which, 30 were new to Sweden. The species and their relative abundance and spatial distribution on sites...... are presented. Two species incriminated as vectors of bluetongue virus, viz. Culicoides obsoletus (about 38%) and Culicoides scoticus (about 36%), were predominant and common in the environment of livestock farms practically all over the Swedish mainland, penetrating far north to at least 65°N. The two species...

Using serological studies to reconstruct the history of bluetongue epidemic in French cattle under successive vaccination campaigns.

Science.gov (United States)

Courtejoie, Noémie; Salje, Henrik; Durand, Benoît; Zanella, Gina; Cauchemez, Simon

2018-05-17

Bluetongue virus is a vector-borne pathogen affecting ruminants that has caused major epidemics in France. Reconstructing the history of bluetongue in French cattle under control strategies such as vaccination has been hampered by the high level of sub-clinical infection, incomplete case data and poor understanding of vaccine uptake over time and space. To tackle these challenges, we used three age-structured serological surveys carried out in cattle (N = 22,342) from ten administrative subdivisions called departments. We fitted catalytic models within a Bayesian MCMC framework to reconstruct the force of seroconversion from infection or vaccination, and the population-level susceptibility per semester between 2007 and 2016. In the departments of the study area, we estimated that 36% of cattle had been infected prior to vaccine rollout that became compulsory from July 2008. The last outbreak case was notified in December 2009, at which time 83% of the animals were seropositive, under the cumulative effect of vaccination and infection. The probability of seroconversion per semester dropped below 10% after 2010 when vaccination became optional. Vaccine uptake was smaller during the 2012 campaign than during the one in 2011, with strong regional contrasts. Eighty four percent of cattle were susceptible when bluetongue re-emerged in 2015. Thus, serological surveys can be used to estimate vaccine uptake and the magnitude of infection, the relative effect of which can sometimes be inferred using prior knowledge on reported incidence and vaccination dates. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Animal viral diseases and global change: Bluetongue and West Nile fever as paradigms

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Miguel Angel eJimenez-Clavero

2012-06-01

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?

EFSA Panel on Animal Health and Welfare (AHAW); Scientific Opinion on bluetongue serotype 8

DEFF Research Database (Denmark)

Bøtner, Anette; Oura, Chris; Saegerman, Claude

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......To answer a question from the European Commission on the potential special characteristics of bluetongue virus (BTV) serotype 8 (BTV-8) compared to other serotypes and their possible impact on the epidemiology of the disease, a systematic literature review was carried out by a working group...... 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...

Genetic characterization of epizootic hemorrhagic disease virus strains isolated from cattle in Israel

Science.gov (United States)

Epizootic hemorrhagic disease virus (EHDV), an Orbivirus not previously reported in Israel, was isolated from Israeli cattle during a “bluetongue like” disease outbreak in 2006. To ascertain the origin of this new virus, three isolates from the outbreak were fully sequenced and compared with availab...

Seroprevalence and S7 gene characterization of bluetongue virus in the West of Iran

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Mohammad Khezri

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

Determination of the minimum protective dose for bluetongue virus serotype 2 and 8 vaccines in sheep.

Science.gov (United States)

Modumo, Jacob; Venter, Estelle H

2012-08-03

Recent outbreaks of bluetongue virus (BTV) serotypes 2 and 8 in many European countries provided an opportunity to investigate the possibility of improving the safety of the modified live vaccines administered mainly in South Africa. Modified live vaccines (MLV) released at a titre of 5 x 104 PFU/mL, raised concerns and prompted the need to determine the minimum titre which will still be protective and also safe. The BTV serotypes 2 and 8 vaccines were produced at the following titres: 102 PFU/mL, 103 PFU/mL and 104 PFU/mL, and were injected into 24 sheep which were then monitored. Blood was collected on days 0, 3, 6, 9, 12, 15, 18, 21, 25, 28 and 4 months post vaccination, for seroconversion and viraemia studies. These sheep were later challenged at 4 months post vaccination using BTV infected cell culture material, they were then observed and bled and again tested for viraemia. There was no viraemia post vaccination, however, a febrile reaction did occur and seroconversion was demonstrated at low titres for both BTV 2 and 8. Although viraemia was demonstrated post challenge, sheep vaccinated with the low titre BTV 2 vaccine showed more than a 90% protection index at a lower titre of 103 PFU/mL, compared with BTV 8 that showed a protection index above 90% at all the titres used. It is recommended that for BTV 2 vaccine, sheep should be vaccinated at a titre of 103 PFU/mL and at a titre of 102 PFU/mL with BTV 8 vaccine.

Entomological research on the vectors of bluetongue disease and the monitoring of activity of Culicoides in the Prishtinë region of Kosova

OpenAIRE

Betim Berisha; Izedin Goga; William P. Taylor; Kurtesh Sherifi; Anthony J. Wilsmore; Driton Çaushi; Beqë Hulaj

2010-01-01

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 plotte...

Sero-epidemiology of bluetongue in Algerian ruminants

African Journals Online (AJOL)

BMH Labo SPA

2016-05-18

May 18, 2016 ... the herds and lack of Culicoides controls strategies were the major risk factors for bluetongue sero- positivity in Algerian ruminant ... coastline at the Mediterranean Sea; most of the coastal area. (northern region) is hilly, .... Culicoides control measures in disease prevention strategy may play a key role in ...

Serological and molecular evidence of bluetongue in sheep and ...

African Journals Online (AJOL)

Dr Molalegne Bitew

2013-05-08

May 8, 2013 ... Organisation for Animal Health (OIE, 2013) and notifiable to veterinary .... The data was collected and stored in Microsoft excel spreadsheet format and analyzed ..... Office International des Epizooties (OIE) (2008). Bluetongue.

Protection of Spanish Ibex (Capra pyrenaica) against Bluetongue Virus Serotypes 1 and 8 in a Subclinical Experimental Infection

Science.gov (United States)

Lorca-Oró, Cristina; Pujols, Joan; García-Bocanegra, Ignacio; Mentaberre, Gregorio; Granados, José Enrique; Solanes, David; Fandos, Paulino; Galindo, Iván; Domingo, Mariano; Lavín, Santiago; López-Olvera, Jorge Ramón

2012-01-01

Many wild ruminants such as Spanish ibex (Capra pyrenaica) are susceptible to Bluetongue virus (BTV) infection, which causes disease mainly in domestic sheep and cattle. Outbreaks involving either BTV serotypes 1 (BTV-1) and 8 (BTV-8) are currently challenging Europe. Inclusion of wildlife vaccination among BTV control measures should be considered in certain species. In the present study, four out of fifteen seronegative Spanish ibexes were immunized with a single dose of inactivated vaccine against BTV-1, four against BTV-8 and seven ibexes were non vaccinated controls. Seven ibexes (four vaccinated and three controls) were inoculated with each BTV serotype. Antibody and IFN-gamma responses were evaluated until 28 days after inoculation (dpi). The vaccinated ibexes showed significant (P<0.05) neutralizing antibody levels after vaccination compared to non vaccinated ibexes. The non vaccinated ibexes remained seronegative until challenge and showed neutralizing antibodies from 7 dpi. BTV RNA was detected in the blood of non vaccinated ibexes from 2 to the end of the study (28 dpi) and in target tissue samples obtained at necropsy (8 and 28 dpi). BTV-1 was successfully isolated on cell culture from blood and target tissues of non vaccinated ibexes. Clinical signs were unapparent and no gross lesions were found at necropsy. Our results show for the first time that Spanish ibex is susceptible and asymptomatic to BTV infection and also that a single dose of vaccine prevents viraemia against BTV-1 and BTV-8 replication. PMID:22666321

Determination of the minimum protective dose for bluetongue virus serotype 2 and 8 vaccines in sheep

Directory of Open Access Journals (Sweden)

Jacob Modumo

2012-08-01

Full Text Available Recent outbreaks of bluetongue virus (BTV serotypes 2 and 8 in many European countries provided an opportunity to investigate the possibility of improving the safety of the modified live vaccines administered mainly in South Africa. Modified live vaccines (MLV released at a titre of 5 x 104 PFU/mL, raised concerns and prompted the need to determine the minimum titre which will still be protective and also safe. The BTV serotypes 2 and 8 vaccines were produced at the following titres: 102 PFU/mL, 103 PFU/mL and 104 PFU/mL, and were injected into 24 sheep which were then monitored. Blood was collected on days 0, 3, 6, 9, 12, 15, 18, 21, 25, 28 and 4 months post vaccination, for seroconversion and viraemia studies. These sheep were later challenged at 4 months post vaccination using BTV infected cell culture material, they were then observed and bled and again tested for viraemia. There was no viraemia post vaccination, however, a febrile reaction did occur and seroconversion was demonstrated at low titres for both BTV 2 and 8. Although viraemia was demonstrated post challenge, sheep vaccinated with the low titre BTV 2 vaccine showed more than a 90% protection index at a lower titre of 103 PFU/mL, compared with BTV 8 that showed a protection index above 90% at all the titres used. It is recommended that for BTV 2 vaccine, sheep should be vaccinated at a titre of 103 PFU/mL and at a titre of 102 PFU/mL with BTV 8 vaccine.

Status of sheep sera to bluetongue, peste des petits ruminants and sheep pox in a few northern states of India

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Vinayagamurthy Balamurugan

2008-09-01

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.

BLUETONGUE VIRUS ANTIBODIES DETECTIONS IN SHEEP FROM ARAÇATUBA REGION –SAO PAULO, BRAZIL DETECÇÃO DE ANTICORPOS CONTRA O VÍRUS DA LÍNGUA AZUL EM OVINOS NA REGIÃO DE ARAÇATUBA – SÃO PAULO, BRASIL

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Adriana Hellmeister de Campos Nogueira

2009-12-01

Full Text Available

Indoor activity of Culicoides associated with livestock in the bluetongue virus (BTV) affected region of northern France during autumn 2006.

Science.gov (United States)

Baldet, T; Delécolle, J C; Cêtre-Sossah, C; Mathieu, B; Meiswinkel, R; Gerbier, G

2008-10-15

In August 2006, bluetongue virus (BTV) was detected in the Netherlands, Belgium, western Germany, Luxembourg and northern France for the first time. Consequently, a longitudinal entomological study was conducted in the affected region of northern France (Ardennes) throughout the autumn of 2006. Data on the spatio-temporal distribution of Culicoides (Diptera: Ceratopogonidae) associated with livestock were collected and an attempt was made to identify the vector(s) involved in BTV transmission by means of virus detection in wild-caught biting midges. Weekly sampling using standardized Onderstepoort-type blacklight traps were performed simultaneously both outdoors and indoors in one BTV-free and three BTV-affected farms between September and December 2006. Culicoides were sorted according to farm, location (outdoors vs. indoors), time point (in weeks), species and physiological stage. BTV detection was conducted by RT-PCR on monospecific pools of non-bloodfed parous female Culicoides. The principal results showed: (i) the absence of the Mediterranean vector, C. imicola, (ii) the relatively low abundance of C. dewulfi and C. pulicaris, (iii) the widespread occurrence and abundance of C. obsoletus/C. scoticus with longevity and behaviour compatible with BTV transmission, and (iv) all Culicoides pools tested for BTV were negative. In France, the very low levels of BTV-8 circulation were probably due to the limited introduction of the virus from affected neighbouring countries, and not due to the absence of local vector populations. A key finding has been the substantiation, for the first time, that Culicoides, and particularly the potential vectors C. obsoletus/C. scoticus and C. dewulfi, can be active at night inside livestock buildings and not only outside, as originally believed. The endophagic tendencies of members of the Obsoletus group are discussed in light of the prolonged period of BTV transmission during the autumn of 2006 and the risk of BTV overwintering and

Epidemiological analysis of the 2006 bluetongue virus serotype 8 epidemic in north-western Europe, A risk map for epidemic potential in the Netherlands

NARCIS (Netherlands)

Koeijer, de A.; Hartemink, N.; Boender, G.J.; Elbers, A.R.W.; Hesterbeek, J.A.P.

2007-01-01

One of the most important aspects of vector-borne infections is the strong influence of weather and climate on the transmission. In response to the major epidemic of bluetongue in north western Europe between summer and autumn 2006, an interest in BTV control issues developed. In this context, a map

Economic comparison of the monitoring programmes for bluetongue vectors in Austria and Switzerland.

Science.gov (United States)

Pinior, B; Brugger, K; Köfer, J; Schwermer, H; Stockreiter, S; Loitsch, A; Rubel, F

2015-05-02

With the bluetongue virus serotype 8 (BTV-8) outbreak in 2006, vector monitoring programmes (according to EU regulation 1266/2007) were implemented by European countries to obtain information on the spatial distribution of vectors and the vector-free period. This study investigates the vector monitoring programmes in Austria and Switzerland by performing a retrospective cost analysis for the period 2006-2010. Two types of costs were distinguished: costs financed directly via the national bluetongue programmes and costs contributed in-kind by the responsible institutions and agricultural holdings. The total net costs of the monitoring programme in Austria amounted to €1,415,000, whereby in Switzerland the costs were valued at €94,000. Both countries followed the legislation complying with requirements, but differed in regard to sampling frequency, number of trap sites and sampling strategy. Furthermore, the surface area of Austria is twice the area of Switzerland although the number of ruminants is almost the same in both countries. Thus, for comparison, the costs were normalised with regard to the sampling frequency and the number of trap sites. Resulting costs per trap sample comprised €164 for Austria and €48 for Switzerland. In both countries, around 50 per cent of the total costs can be attributed to payments in-kind. The benefit of this study is twofold: first, veterinary authorities may use the results to improve the economic efficiency of future vector monitoring programmes. Second, the analysis of the payment in-kind contribution is of great importance to public authorities as it makes the available resources visible and demonstrates how they have been used. British Veterinary Association.

Susceptibility of North American white-tailed deer to the Netherlands strain of BTV serotype 8

Science.gov (United States)

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 ...

Epidemiological characteristics and clinicopathological features of bluetongue in sheep and cattle, during the 2014 BTV serotype 4 incursion in Greece.

Science.gov (United States)

Katsoulos, Panagiotis-Dimitrios; Giadinis, Nektarios D; Chaintoutis, Serafeim C; Dovas, Chrysostomos I; Kiossis, Evangelos; Tsousis, Georgios; Psychas, Vassilios; Vlemmas, Ioannis; Papadopoulos, Theologos; Papadopoulos, Orestis; Zientara, Stéphan; Karatzias, Harilaos; Boscos, Constantinos

2016-03-01

During 2014, an outbreak of Bluetongue virus (BTV) infections attributed to serotype 4 occurred in Greece and spread to south-eastern Europe. In the present article, the clinical and epidemiological data of 15 sheep flocks and 5 dairy cattle herds affected in Greece are described. In sheep, the most frequent clinical signs observed were fever, hyporexia, and edema of the face. A number of clinically affected sheep had chronic laminitis resulting in chronic lameness. Confirmation of suspect clinical cases was performed using BTV-specific real-time RT-PCR, and serotype 4-specific RT-PCR. The average morbidity of bluetongue in the sheep flocks was estimated to be 15.3 % (95 % C.I. 6.8-23.8 %) and the average mortality and case fatality were 4.5 % (95 % C.I. 1.5-7.6 %) and 32.0 % (95 % C.I. 18.1-42.9 %), respectively. The BTV seroprevalence and the ratio of clinical manifestations-to-infections determined in seven of these flocks, were on average 36.5 % (95 % C.I. 15.7-57.3 %) and 24.6 % (95 % C.I. 12.8-36.3 %). BTV ratio of clinical manifestations-to-infections was higher in the imported western European sheep breeds examined compared to the local ones. In dairy cattle, the average herd prevalence of viremia was 48.8 % (95 % C.I. 15.3-82.4 %) and none had signs associated with bluetongue. The results of this study indicate that the 2014 Greek BTV-4 has significant impact on the health status and the viability of sheep in affected flocks but does not cause clinical signs in cattle, despite the high prevalence of viremia.

Les porcheries : réservoirs des Culicoides (Diptera : Ceratopogonidae, vecteurs des virus de la Maladie de la Langue bleue et de Schmallenberg ?

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Zimmer, JY.

2014-01-01

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.

Cost analysis of bluetongue virus serotype 8 surveillance and vaccination programmes in Austria from 2005 to 2013.

Science.gov (United States)

Pinior, Beate; Lebl, Karin; Firth, Clair; Rubel, Franz; Fuchs, Reinhard; Stockreiter, Simon; Loitsch, Angelika; Köfer, Josef

2015-11-01

This study was designed to evaluate the costs between 2005 and 2013 of the national bluetongue virus (BTV) surveillance and vaccination programmes before, during and after the BTV serotype 8 (BTV-8) outbreak in Austria commencing in 2008. In addition to an assessment of the temporal development of costs, a spatial cost analysis was performed. Within the context of this study, the term 'costs' refers to actual financial expenditure and imputed monetary costs for contributions in-kind. Costs were financed directly by the private-public sectors, by the European Commission (EC), and (in-kind) by responsible national institutions and individuals (e.g. blood sampling by veterinarians). The total net cost of the BTV-8 surveillance and vaccination programmes arising from the outbreak amounted to €22.8 million (0.86% of the national agricultural Gross Value Added), of which 32% was allocated to surveillance and 68% to the vaccination programme. Of the total programme costs, the EC supplied €4.9 million, while the remaining costs (€18 million) were directly financed from national resources. Of the latter, €14.5 million was classed as public costs, including €2 million contributions in-kind, and €3.4 million as private costs. The assessment of the costs revealed heterogeneous temporal and spatial distributions. The methodology of this analysis might assist decision makers in calculating costs for other surveillance and intervention programmes. The assessment of contributions in-kind is of importance to public authorities as it increases visibility of the available resources and shows how they have been employed. This study also demonstrates the importance of tracking changing costs per payer over time. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Estimating front-wave velocity of infectious diseases: a simple, efficient method applied to bluetongue.

Science.gov (United States)

Pioz, Maryline; Guis, Hélène; Calavas, Didier; Durand, Benoît; Abrial, David; Ducrot, Christian

2011-04-20

Understanding the spatial dynamics of an infectious disease is critical when attempting to predict where and how fast the disease will spread. We illustrate an approach using a trend-surface analysis (TSA) model combined with a spatial error simultaneous autoregressive model (SAR(err) model) to estimate the speed of diffusion of bluetongue (BT), an infectious disease of ruminants caused by bluetongue virus (BTV) and transmitted by Culicoides. In a first step to gain further insight into the spatial transmission characteristics of BTV serotype 8, we used 2007-2008 clinical case reports in France and TSA modelling to identify the major directions and speed of disease diffusion. We accounted for spatial autocorrelation by combining TSA with a SAR(err) model, which led to a trend SAR(err) model. Overall, BT spread from north-eastern to south-western France. The average trend SAR(err)-estimated velocity across the country was 5.6 km/day. However, velocities differed between areas and time periods, varying between 2.1 and 9.3 km/day. For more than 83% of the contaminated municipalities, the trend SAR(err)-estimated velocity was less than 7 km/day. Our study was a first step in describing the diffusion process for BT in France. To our knowledge, it is the first to show that BT spread in France was primarily local and consistent with the active flight of Culicoides and local movements of farm animals. Models such as the trend SAR(err) models are powerful tools to provide information on direction and speed of disease diffusion when the only data available are date and location of cases.

Inactivation by gamma irradiation of animal viruses in simulated laboratory effluent

International Nuclear Information System (INIS)

Thomas, F.C.; Ouwerkerk, T.; McKercher, P.

1982-01-01

Several animal viruses were treated with gamma radiation from a 60 Co source under conditions which might be found in effluent from an animal disease laboratory. Swine vesicular disease virus, vesicular stomatitis virus, and blue-tongue virus were irradiated in tissues from experimentally infected animals. Pseudorabies virus, fowl plague virus, swine vesicular disease virus, and vesicular stomatitis virus were irradiated in liquid animal feces. All were tested in animals and in vitro. The D 10 values, that is, the doses required to reduce infectivity by 1 log 10 , were not apparently different from those expected from predictions based on other data and theoretical considerations. The existence of the viruses in pieces of tissues or in liquid feces made no differences in the efficacy of the gamma radiation for inactivating them. Under the ''worst case'' conditions (most protective for virus) simulated in this study, no infectious agents would survive 4.0 Mrads

Culicoides and the Tartar Steppe: Il Deserto dei Tartari Culicoides and the spread of blue tongue virus.

Science.gov (United States)

Houin, R

2008-12-01

Culicoides were described for the first time in England in 1713, but named by Latreille in 1809 only. Even so, they were better known as Ceratopogon until Kieffer reintroduced the name Culicoides. The family name became Ceratopogonidae, the description by Meigen (1803) being better adapted to that systematic level. Culicoides were considered simply as biting insects until it was found that they can carry filaria and viruses. In 1944, du Toit in Transvaal described their role in the transmission of blue-tongue virus. Blue-tongue disease has since extended progressively northward from South Africa, disseminated by Culicoides imicola. At the end of the 20th century, it reached the southern shores of the Mediterranean sea, and has since threatened the southern Europe. Surveillance and prevention procedures were put in place, but fortress Europe was taken breached when a different strain of the virus entered through Belgium in 2006. Transmitted by local Culicoides species that were aggressive and abundant, the disease spread quickly, in a disastrous epizootic southward through more than half of France. Westward, infected insects have been carried by wind over the Channel, introducing the disease to England.

Inactivation of RNA viruses by gamma irradiation

International Nuclear Information System (INIS)

Nonomiya, Takashi; Morimoto, Akinori; Iwatsuki, Kazuo; Tsutsumi, Takamasa; Ito, Hitoshi; Yamashiro, Tomio; Ishigaki, Isao.

1992-01-01

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 D 10 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)

Inactivation of RNA viruses by gamma irradiation

Energy Technology Data Exchange (ETDEWEB)

Nonomiya, Takashi; Morimoto, Akinori; Iwatsuki, Kazuo; Tsutsumi, Takamasa (Ministry of Agriculture, Forestry and fisheries, Yokohama, Kanagawa (Japan). Animal Quarantine Service); Ito, Hitoshi; Yamashiro, Tomio; Ishigaki, Isao

1992-09-01

Four kinds of RNA viruses, Bluetongue virus (BT), Bovine Virus Diarrhea-Mucosal Disease virus (BVD[center dot]MD), Bovine Respiratory Syncytial virus (RS), Vesicular Stmatitis virus (VS), were subjected to various doses of gamma irradiation to determine the lethal doses. The D[sub 10] 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).

Infección por el virus de la Lengua azul: activación de señales celulares que inducen apoptosis Bluetongue virus infection: signaling pathway activated during apoptosis

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E. Mortola

2009-09-01

Full Text Available El virus de la Lengua azul (VLA es un ARN virus de doble cadena que induce apoptosis tanto en cultivos celulares como en tejidos blanco. Con el fin de dilucidar el mecanismo de apoptosis en la infección por el VLA, en el presente trabajo examinamos en detalle, por la técnica de Western blot, las señales celulares de caspasas, Bax, citocromo c, Smac/DIABLO y factor nuclear kappa B (NF-kB que se activan en la infección viral. Hemos comprobado que luego de la infección in vitro con el VLA, se detectó la activación de la caspasa 8 y con ello el mecanismo extrínseco de la apoptosis. También detectamos por primera vez no sólo la activación de miembros de la familia Bcl-2 (Bax, sino también la liberación del citocromo c y la proteína Smac/DIABLO, confirmando que en la infección por el VLA está involucrado el mecanismo secuencial intrínseco de la apoptosis. Asimismo, demostramos que la infección por el VLA activa el NF-kB y que la apoptosis es sustancialmente reducida mediante la inhibición del mismo. La activación de las señales celulares tales como Bax, citocromo c, Smac/DIABLO y NF-kB presentados en este trabajo, esclarecen los mecanismos apoptóticos durante la infección por el VLA para una mayor comprensión del papel primario que juega la apoptosis en la patogénesis del virus.Bluetongue (BTV is a double-stranded RNA virus that induces apoptosis both in mammalian cell cultures and in target tissues. To elucidate the apoptosis pathways in BTV infection, we have examined in detail the apoptosis mechanism by examination of caspases, Bax, cytochrome c, Smac/DIABLO and NF-kB signalling pathways. In this report, after cell infection with BTV, the activation of caspase 8 was detected, proving the extrinsic receptor binding apoptotic pathway. Apoptosis followed a sequential pathway involving the detection of activated Bcl-2 family members. Furthermore, its translocation to the mitochondria, as well as the release of cytochrome c and

Why did bluetongue spread the way it did? Environmental factors influencing the velocity of bluetongue virus serotype 8 epizootic wave in France.

Science.gov (United States)

Pioz, Maryline; Guis, Hélène; Crespin, Laurent; Gay, Emilie; Calavas, Didier; Durand, Benoît; Abrial, David; Ducrot, Christian

2012-01-01

Understanding where and how fast an infectious disease will spread during an epidemic is critical for its control. However, the task is a challenging one as numerous factors may interact and drive the spread of a disease, specifically when vector-borne diseases are involved. We advocate the use of simultaneous autoregressive models to identify environmental features that significantly impact the velocity of disease spread. We illustrate this approach by exploring several environmental factors influencing the velocity of bluetongue (BT) spread in France during the 2007-2008 epizootic wave to determine which ones were the most important drivers. We used velocities of BT spread estimated in 4,495 municipalities and tested sixteen covariates defining five thematic groups of related variables: elevation, meteorological-related variables, landscape-related variables, host availability, and vaccination. We found that ecological factors associated with vector abundance and activity (elevation and meteorological-related variables), as well as with host availability, were important drivers of the spread of the disease. Specifically, the disease spread more slowly in areas with high elevation and when heavy rainfall associated with extreme temperature events occurred one or two months prior to the first clinical case. Moreover, the density of dairy cattle was correlated negatively with the velocity of BT spread. These findings add substantially to our understanding of BT spread in a temperate climate. Finally, the approach presented in this paper can be used with other infectious diseases, and provides a powerful tool to identify environmental features driving the velocity of disease spread.

Bluetongue virus serotype 1 outbreak in the Basque Country (Northern Spain 2007-2008. Data support a primary vector windborne transport.

Directory of Open Access Journals (Sweden)

Rodrigo García-Lastra

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.

Anticorpos contra o vírus da língua azul em bovinos do sertão da Paraíba

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Melo C.B.

2000-01-01

Full Text Available In June of 1997 the prevalence of antibodies to bluetongue virus was between 3.94 and 4.82% in 137 bovine serum samples from 12 herds in Paraiba State, Brazil. This is the first report of antibodies to bluetongue virus in Paraiba State herds.

Prevalence and Risk Factors of Brucellosis, Chlamydiosis, and Bluetongue Among Sika Deer in Jilin Province in China.

Science.gov (United States)

Liu, Fei; Li, Jian-Ming; Zeng, Fan-Li; Zong, Ying; Leng, Xue; Shi, Kun; Diao, Nai-Chao; Li, Dong; Li, Bo-Yu; Zhao, Quan; Du, Rui

2018-04-01

Brucellosis and chlamydiosis are important zoonotic diseases and bluetongue virus (BTV) is an arthropod-borne viral disease of ruminants. They are widely distributed around the world, cause large economic losses, and significant harmful effects on humans. However, epidemiological information relating to transmission from commercial sika deer in China is limited. Therefore, from 2016 to 2017, 458 sika deer blood samples were collected from three cities in Jilin Province in China. The Brucella antigen and specific antibodies to Chlamydia and BTV were examined using RT-PCR, indirect hemagglutination assay, and ELISA, respectively. The prevalence of Brucella was found to be 12.9% (59/458) and the seroprevalence of Chlamydia and BTV was 14.4% (66/458) and 17.0% (78/458), respectively. Seasonality was considered a risk factor for the presence of Brucella or BTV in sika deer and the region was considered a risk factor for Chlamydia infection. These data provides reference values for both further research and disease control.

Bluetongue Virus Serotype 1 Outbreak in the Basque Country (Northern Spain) 2007–2008. Data Support a Primary Vector Windborne Transport

Science.gov (United States)

García-Lastra, Rodrigo; Leginagoikoa, Iratxe; Plazaola, Jose M.; Ocabo, Blanca; Aduriz, Gorka; Nunes, Telmo; Juste, Ramón A.

2012-01-01

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. PMID:22479628

Comparisons of competitive enzyme-linked immunosorbent assay ...

African Journals Online (AJOL)

Bluetongue is a noncontagious, arthropod-borne viral disease of both domestic and wild ruminants. Bluetongue virus (BTV) is the type of species of the genus Orbivirus within the family Reoviridae. BTV is endemic in some areas with cattle and wild ruminants serving as reservoirs for the virus. Clinical symptoms are often ...

Climate change and the spread of vector-borne diseases: using approximate Bayesian computation to compare invasion scenarios for the bluetongue virus vector Culicoides imicola in Italy.

Science.gov (United States)

Mardulyn, Patrick; Goffredo, Maria; Conte, Annamaria; Hendrickx, Guy; Meiswinkel, Rudolf; Balenghien, Thomas; Sghaier, Soufien; Lohr, Youssef; Gilbert, Marius

2013-05-01

Bluetongue (BT) is a commonly cited example of a disease with a distribution believed to have recently expanded in response to global warming. The BT virus is transmitted to ruminants by biting midges of the genus Culicoides, and it has been hypothesized that the emergence of BT in Mediterranean Europe during the last two decades is a consequence of the recent colonization of the region by Culicoides imicola and linked to climate change. To better understand the mechanism responsible for the northward spread of BT, we tested the hypothesis of a recent colonization of Italy by C. imicola, by obtaining samples from more than 60 localities across Italy, Corsica, Southern France, and Northern Africa (the hypothesized source point for the recent invasion of C. imicola), and by genotyping them with 10 newly identified microsatellite loci. The patterns of genetic variation within and among the sampled populations were characterized and used in a rigorous approximate Bayesian computation framework to compare three competing historical hypotheses related to the arrival and establishment of C. imicola in Italy. The hypothesis of an ancient presence of the insect vector was strongly favoured by this analysis, with an associated P ≥ 99%, suggesting that causes other than the northward range expansion of C. imicola may have supported the emergence of BT in southern Europe. Overall, this study illustrates the potential of molecular genetic markers for exploring the assumed link between climate change and the spread of diseases. © 2013 Blackwell Publishing Ltd.

Schmallenberg virus infection of ruminants: challenges and opportunities for veterinarians

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Claine F

2015-06-01

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

Retrospective analysis of Bluetongue farm risk profile definition, based on biology, farm management practices and climatic data.

Science.gov (United States)

Cappai, Stefano; Loi, Federica; Coccollone, Annamaria; Contu, Marino; Capece, Paolo; Fiori, Michele; Canu, Simona; Foxi, Cipriano; Rolesu, Sandro

2018-07-01

Bluetongue (BT) is a vector-borne disease transmitted by species of Culicoides midges (Diptera: Ceratopogonidae). Many studies have contributed to clarifying various aspects of its aetiology, epidemiology and vector dynamic; however, BT remains a disease of epidemiological and economic importance that affects ruminants worldwide. Since 2000, the Sardinia region has been the most affected area of the Mediterranean basin. The region is characterised by wide pastoral areas for sheep and represents the most likely candidate region for the study of Bluetongue virus (BTV) distribution and prevalence in Italy. Furthermore, specific information on the farm level and epidemiological studies needs to be provided to increase the knowledge on the disease's spread and to provide valid mitigation strategies in Sardinia. This study conducted a punctual investigation into the spatial patterns of BTV transmission to define a risk profile for all Sardinian farmsby using a logistic multilevel mixed model that take into account agro-meteorological aspects, as well as farm characteristics and management. Data about animal density (i.e. sheep, goats and cattle), vaccination, previous outbreaks, altitude, land use, rainfall, evapotranspiration, water surface, and farm management practices (i.e. use of repellents, treatment against insect vectors, storage of animals in shelter overnight, cleaning, presence of mud and manure) were collected for 12,277 farms for the years 2011-2015. The logistic multilevel mixed model showed the fundamental role of climatic factors in disease development and the protective role of good management, vaccination, outbreak in the previous year and altitude. Regional BTV risk maps were developed, based on the predictor values of logistic model results, and updated every 10 days. These maps were used to identify, 20 days in advance, the areas at highest risk. The risk farm profile, as defined by the model, would provide specific information about the role of each

Modelling spread of Bluetongue and other vector borne diseases in Denmark and evaluation of intervention strategies

DEFF Research Database (Denmark)

Græsbøll, Kaare

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......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....... 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 predictive power...

Current and next-generation bleutongue vaccines

NARCIS (Netherlands)

Feenstra, Femke; Rijn, van P.A.

2017-01-01

Bluetongue virus (BTV) causes the hemorrhagic disease bluetongue (BT) in ruminants. The best way to control outbreaks is vaccination. Currently, conventionally modified-live and inactivated vaccines are commercially available, which have been successfully used to control BT, but nonetheless have

The Dutch strain of BTV-8 in white-tailed deer

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Bluetongue virus (BTV), family Reoviridae, genus Orbivirus, contains ten double stranded RNA segments encoding at least ten viral proteins. Bluetongue (BT) is an arthropod-borne disease; transmission to ruminants, including cattle, sheep, goats, and deer species by bites of species of Culicoides. In...

Multiplex RT-PCR and Automated Microarray for Detection of Eight Bovine Viruses.

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Lung, O; Furukawa-Stoffer, T; Burton Hughes, K; Pasick, J; King, D P; Hodko, D

2017-12-01

Microarrays can be a useful tool for pathogen detection as it allow for simultaneous interrogation of the presence of a large number of genetic sequences in a sample. However, conventional microarrays require extensive manual handling and multiple pieces of equipment for printing probes, hybridization, washing and signal detection. In this study, a reverse transcription (RT)-PCR with an accompanying novel automated microarray for simultaneous detection of eight viruses that affect cattle [vesicular stomatitis virus (VSV), bovine viral diarrhoea virus type 1 and type 2, bovine herpesvirus 1, bluetongue virus, malignant catarrhal fever virus, rinderpest virus (RPV) and parapox viruses] is described. The assay accurately identified a panel of 37 strains of the target viruses and identified a mixed infection. No non-specific reactions were observed with a panel of 23 non-target viruses associated with livestock. Vesicular stomatitis virus was detected as early as 2 days post-inoculation in oral swabs from experimentally infected animals. The limit of detection of the microarray assay was as low as 1 TCID 50 /ml for RPV. The novel microarray platform automates the entire post-PCR steps of the assay and integrates electrophoretic-driven capture probe printing in a single user-friendly instrument that allows array layout and assay configuration to be user-customized on-site. © 2016 Her Majesty the Queen in Right of Canada.

Functional validation of Apoptosis Genes IAP1 and DRONC in midgut tissue of the biting midge Culicoides sonorensis (Diptera: Ceratopogonidae) by RNAi

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Background: Culicoides biting midges transmit multiple ruminant viruses, including bluetongue virus and epizootic hemorrhagic disease virus, causing significant economic burden worldwide due to trade restrictions and production loss. To limit the spread of these viruses, control strategies focus on ...

Cost distribution of bluetongue surveillance and vaccination programmes in Austria and Switzerland (2007–2016)

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Pinior, Beate; Loitsch, Angelika; Stockreiter, Simon; Hutter, Sabine; Richter, Veronika; Lebl, Karin; Schwermer, Heinzpeter; Käsbohrer, Annemarie

2018-01-01

Bluetongue virus (BTV) is an emerging transboundary disease in Europe, which can cause significant production losses among ruminants. The analysis presented here assessed the costs of BTV surveillance and vaccination programmes in Austria and Switzerland between 2007 and 2016. Costs were compared with respect to time, type of programme, geographical area and who was responsible for payment. The total costs of the BTV vaccination and surveillance programmes in Austria amounted to €23.6 million, whereas total costs in Switzerland were €18.3 million. Our analysis demonstrates that the costs differed between years and geographical areas, both within and between the two countries. Average surveillance costs per animal amounted to approximately €3.20 in Austria compared with €1.30 in Switzerland, whereas the average vaccination costs per animal were €6.20 in Austria and €7.40 in Switzerland. The comparability of the surveillance costs is somewhat limited, however, due to differences in each nation’s surveillance (and sampling) strategy. Given the importance of the export market for cattle production, investments in such programmes are more justified for Austria than for Switzerland. The aim of the retrospective assessment presented here is to assist veterinary authorities in planning and implementing cost-effective and efficient control strategies for emerging livestock diseases. PMID:29363572

Seasonal drivers of the epidemiology of arthropod-borne viruses in Australia.

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Jemma L Geoghegan

2014-11-01

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.

Apyrase activity and adenosine diphosphate induced platelet aggregation inhibition by the salivary gland proteins of Culicoides variipennis, the North American vector of bluetongue viruses.

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Pérez de León, A A; Tabachnick, W J

1996-02-01

Salivary gland homogenates of Culicoides variipennis, the primary vector of bluetongue (BLU) viruses in North America, were analyzed for apyrase activity. Apyrase (ATP diphosphohydrolase, EC 3.6.1.5) is an anti-hemostatic and anti-inflammatory salivary enzyme of most hematophagous arthropods. The enzyme activity was measured by the release of orthophosphate using ATP, ADP, and AMP as substrates with Ca2+ as the divalent cation. ATPase (11.5 +/- 1 mU/pair of glands), ADPase (7.3 +/- 0.7 mU/pair of glands), and insignificant (P < 0.05) AMPase (0.07 mU/pair of glands) activities were detected in female salivary glands. Male salivary glands contained lower amounts of ATPase and ADPase activity (P < 0.05). The ATPase and ADPase activities were greatest at pH 8.5, and were similarly activated by Mg2+. Molecular sieving HPLC of salivary gland homogenates generated a single peak which coincided with ATPase and ADPase, but no AMPase, activity; the protein has an estimated molecular mass of 35,000 Da. ATPase and ADPase activity, and total protein concentration, were reduced (P < 0.05) in the salivary glands of females after taking a blood meal from a sheep. Salivary gland homogenates also inhibited ADP-induced platelet aggregation in vitro. It is concluded that the salivary ATPase and ADPase activities of C. variipennis reside in one enzyme, and that this enzyme is likely an apyrase. The apyrase activity is thought to be responsible for the inhibition of ADP-induced platelet aggregation, as indicated by the apparent discharge of apyrase from salivary glands into the host during blood feeding. This suggests that apyrase is one of the salivary proteins present in C. variipennis acting as antigens in the development of Culicoides hypersensitivity in ruminants and horses. Apyrase may inhibit an inflammatory response at the feeding site through the subsequent degradation of its end-product, AMP, to adenosine, a potent anti-inflammatory substance, by the ecto-5' nucleotidase

Cost distribution of bluetongue surveillance and vaccination programmes in Austria and Switzerland (2007-2016).

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Pinior, Beate; Firth, Clair L; Loitsch, Angelika; Stockreiter, Simon; Hutter, Sabine; Richter, Veronika; Lebl, Karin; Schwermer, Heinzpeter; Käsbohrer, Annemarie

2018-03-03

Bluetongue virus (BTV) is an emerging transboundary disease in Europe, which can cause significant production losses among ruminants. The analysis presented here assessed the costs of BTV surveillance and vaccination programmes in Austria and Switzerland between 2007 and 2016. Costs were compared with respect to time, type of programme, geographical area and who was responsible for payment. The total costs of the BTV vaccination and surveillance programmes in Austria amounted to €23.6 million, whereas total costs in Switzerland were €18.3 million. Our analysis demonstrates that the costs differed between years and geographical areas, both within and between the two countries. Average surveillance costs per animal amounted to approximately €3.20 in Austria compared with €1.30 in Switzerland, whereas the average vaccination costs per animal were €6.20 in Austria and €7.40 in Switzerland. The comparability of the surveillance costs is somewhat limited, however, due to differences in each nation's surveillance (and sampling) strategy. Given the importance of the export market for cattle production, investments in such programmes are more justified for Austria than for Switzerland. The aim of the retrospective assessment presented here is to assist veterinary authorities in planning and implementing cost-effective and efficient control strategies for emerging livestock diseases. © British Veterinary Association (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Two-host, two-vector basic reproduction ratio (R(0 for bluetongue.

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Joanne Turner

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.

An early warning system for incursions of Bluetongue disease to the UK

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Burgin, Laura; Sanders, Christopher; Carpenter, Simon; Mellor, Philip; Gloster, John

2010-05-01

Since 2006 northern Europe has been in the midst of an extensive epidemic of the animal disease, Bluetongue, which has cost the European economy hundreds of millions of euros due to death, sickness and movement restrictions of livestock. Bluetongue is spread by biting midges which can be carried for hundreds of kilometers on the wind. A scheme within the UK Met Office's dispersion model, the Numerical Atmospheric-dispersion Modelling Environment (NAME), has been developed to reflect the effects of meteorology on the long-distance transport of these midge vectors. The scheme is based on data from field and laboratory experiments carried out at the Institute for Animal Health, Pirbright. From these experiments, certain threshold values which define when midges do not become airborne have been obtained for several meteorological variables. Within NAME, particles representing midges are removed from the model atmosphere if these thresholds are exceeded. Following outbreaks of the disease in Belgium and the Netherlands in 2006, an early-warning website was developed based on the model, to provide the UK Department for Environment, Food and Rural Affairs (Defra) advance knowledge of potential disease incursions by infected midges carried on the wind across the English Channel. The service has been in daily operation since April 2007 and correctly warned of the high risk of an incursion of infected midges causing the first UK outbreak in Suffolk on 4 August 2007. The website has since been expanded to predict potential incursions of disease into the Channel Islands and Northern Ireland and was used to inform on vaccination policy decisions by Defra and the Scottish government.

Using animal performance data to evidence the under-reporting of case herds during an epizootic: application to an outbreak of bluetongue in cattle.

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Simon Nusinovici

Full Text Available Following the emergence of the Bluetongue virus serotype 8 (BTV-8 in France in 2006, a surveillance system (both passive and active was implemented to detect and follow precociously the progression of the epizootic wave. This system did not allow a precise estimation of the extent of the epizootic. Infection by BTV-8 is associated with a decrease of fertility. The objective of this study was to evaluate whether a decrease in fertility can be used to evidence the under-reporting of cases during an epizootic and to quantify to what extent non-reported cases contribute to the total burden of the epizootic. The cow fertility in herds in the outbreak area (reported or not was monitored around the date of clinical signs. A geostatistical interpolation method was used to estimate a date of clinical signs for non-reported herds. This interpolation was based on the spatiotemporal dynamic of confirmed case herds reported in 2007. Decreases in fertility were evidenced for both types of herds around the date of clinical signs. In non-reported herds, the decrease fertility was large (60% of the effect in reported herds, suggesting that some of these herds have been infected by the virus during 2007. Production losses in non-reported infected herds could thus contribute to an important part of the total burden of the epizootic. Overall, results indicate that performance data can be used to evidence the under-reporting during an epizootic. This approach could be generalized to pathogens that affect cattle's performance, including zoonotic agents such as Coxiella burnetii or Rift Valley fever virus.

Spatial and temporal variation in the abundance of Culicoides biting midges (Diptera: Ceratopogonidae) in nine European countries

DEFF Research Database (Denmark)

Cuellar, Ana Carolina; Kjær, Lene Jung; Kirkeby, Carsten Thure

2018-01-01

Biting midges of the genus Culicoides (Diptera: Ceratopogonidae) are vectors of bluetongue virus (BTV), African horse sickness virus and Schmallenberg virus (SBV). Outbreaks of both BTV and SBV have affected large parts of Europe. The spread of these diseases depends largely on vector distributio...

Prevalence of serotype specific antibody to equine encephalosis virus in Thoroughbred yearlings South Africa (1999-2004

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P. G. Howell

2008-08-01

Full Text Available Cohorts of yearlings were sampled over a period of 6 years in a retrospective serological survey to establish the annual prevalence of serotype specific antibody to equine encephalosis virus on Thoroughbred stud farms distributed within defined geographical regions of South Africa. Seasonal seroprevalence varied between 3.6% and 34.7%, revealing both single and multiple serotype infections in an individual yearling. During the course of this study serotypes 1 and 6 were most frequently and extensively identified while the remaining serotypes 2, 3, 4, 5 and 7 were all identified as sporadic and localized in fections affecting only individual horses. This study of the seasonal prevalence of equine encephalosis virus has a corollary and serves as a useful model in the seasonal incidence of the serotypes of African horse sickness and bluetongue in regions where the respective diseases are endemic.

Bluetongue control using vaccines: the experience of Emilia Romagna, Italy.

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Santi, A; Piccolomini, L Loli; Viappiani, P; Tamba, M; Calabrese, R; Massirio, I

2004-01-01

In 2003, thirty municipalities of the provinces of Parma, Reggio Emilia and Modena in the Emilia Romagna region of Italy, bordering the region of Tuscany, were included in the national bluetongue (BT) vaccination programme, using monovalent live-attenuated type 2 vaccine. The purpose of the study was to evaluate the organisation of a vaccination programme designed by the Regional Veterinary Service and the relative cost of the campaign, as a large number of animals were involved. To better evaluate the real cost of the campaign, costs sustained by the Reggio Emilia Local Sanitary Unit were specifically analysed. BT vaccination of all domestic ruminants is a very expensive operation (euro9.20 per vaccinated animal). Consequently, to evaluate the need for a vaccination campaign in a new area, the risk of disease spread, as well as the cost of the operation, should be considered.

Entomological research on the vectors of bluetongue disease and the monitoring of activity of Culicoides in the Prishtinë region of Kosova

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Betim Berisha

2010-12-01

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.

Molecular and Serological Survey of Selected Viruses in Free-Ranging Wild Ruminants in Iran.

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Farhid Hemmatzadeh

Full Text Available A molecular and serological survey of selected viruses in free-ranging wild ruminants was conducted in 13 different districts in Iran. Samples were collected from 64 small wild ruminants belonging to four different species including 25 Mouflon (Ovis orientalis, 22 wild goat (Capra aegagrus, nine Indian gazelle (Gazella bennettii and eight Goitered gazelle (Gazella subgutturosa during the national survey for wildlife diseases in Iran. Serum samples were evaluated using serologic antibody tests for Peste de petits ruminants virus (PPRV, Pestiviruses [Border Disease virus (BVD and Bovine Viral Diarrhoea virus (BVDV], Bluetongue virus (BTV, Bovine herpesvirus type 1 (BHV-1, and Parainfluenza type 3 (PI3. Sera were also ELISA tested for Pestivirus antigen. Tissue samples including spleen, liver, lung, tonsils, mesenteric and mediastinal lymph nodes and white blood cells (WBCs were tested using polymerase chain reaction (PCR for PPRV, Foot and Mouth Disease virus (FMDV, Pestivirus, BTV, Ovine herpesvirus type 2 (OvHV-2 and BHV-1. Serologic tests were positive for antibodies against PPRV (17%, Pestiviruses (2% and BTV (2%. No antibodies were detected for BHV-1 or PI3, and no Pestivirus antigen was detected. PCR results were positive for PPRV (7.8%, FMDV (11%, BTV (3%, OvHV-2 (31% and BHV-1 (1.5%. None of the samples were positive for Pestiviruses.

Description and implementation of a surveillance network for bluetongue in the Balkans and in adjoining areas of south-eastern Europe.

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Dall'Acqua, F; Paladini, C; Meiswinkel, R; Savini, L; Calistri, P

2006-01-01

During the recent severe outbreaks of bluetongue (BT) in the Mediterranean Basin, the BT virus (BTV) spread beyond its historical limits into the Balkan region. One of the primary impacts of BT is the cessation in livestock trade which can have severe economic and social consequences. The authors briefly describe the development of the collaborative East-BTnet programme which aims to assist all affected and at-risk Balkan states and adjoining countries in the management of BT, and in the development of individual national surveillance systems. The beneficiary countries involved, and led by the World organisation for animal health (Office International des Epizooties) Collaborating Centre for veterinary training, epidemiology, food safety and animal welfare of the Istituto Zooprofilattico dell'Abruzzo e del Molise 'G. Caporale' in collaboration with the Institute for the Protection and the Security of the Citizen, the European Commission Joint Research Centre (IPSC-JRC), were Albania, Bosnia-Herzegovina, Bulgaria, Croatia, Cyprus, the Former Yugoslavia Republic of Macedonia, Kosovo, Malta, Romania, Serbia and Montenegro, Slovenia and Turkey. A regional web-based surveillance network is a valuable tool for controlling and managing transboundary animal diseases such as BT. Its implementation in the Balkan region and in adjoining areas of south-eastern Europe is described and discussed.

A serosurvey of bluetongue and epizootic haemorrhagic disease in a convenience sample of sheep and cattle herds in Zimbabwe.

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Gordon, Stuart J G; Bolwell, Charlotte; Rogers, Chris W; Musuka, Godfrey; Kelly, Patrick; Guthrie, Alan; Mellor, Philip S; Hamblin, Chris

2017-11-14

A convenience sample of sheep and cattle herds around the cities of Harare, Kwekwe and Bulawayo, located in the Highveld region of Zimbabwe, was used to estimate the seroprevalence and sero-incidence of bluetongue virus (BTV) and epizootic haemorrhagic disease virus (EHDV) antibodies. A competitive enzyme-linked immunosorbent assay was used to identify serum antibodies against BTV and EHDV across three rainy seasons. The median sero-prevalence of BTV and EHDV antibodies in cattle was 62% (interquartile range [IQR]: 30-89) and 56% (IQR: 5-77), respectively. In sheep, the median sero-prevalence of BTV and EHDV was 41% (IQR: 19-63) and 0% (IQR: 0-21), respectively. Median sero-incidences of BTV and EHDV antibodies in cattle of 43% (IQR: 22-67) and 27% (IQR: 9-57) respectively were recorded. The median sero-incidence of BTV in sheep was 14% (IQR: 6-23). Based on these preliminary findings, animal health workers in Zimbabwe should continue to monitor the exposure rates of cattle and sheep to BTV and consider the possibility of strains emerging with increased pathogenicity. There are no previous published reports of antibodies against EHDV in Zimbabwe so the possibility of epizootic haemorrhagic disease existing in domestic livestock should now be considered by Zimbabwean animal health officials. Seroconversions to BTV and EHDV occurred predominantly at the end of each rainy season (March and April), which generally corresponds to high numbers of the Culicoides vectors. BTV isolations were made from three individual cows in two of the sentinel herds and all three were identified as serotype 3. This is the first time BTV serotype 3 has been recorded in Zimbabwe, although its presence in neighbouring South Africa is well documented.

Animal viral diseases and global change: bluetongue and West Nile fever as paradigms.

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Jiménez-Clavero, Miguel Á

2012-01-01

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 (BT) and West Nile fever/encephalitis (WNF), 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. BT, affecting domestic ruminants, has recently afflicted livestock in Europe in an unprecedented epizootic, causing enormous economic losses. WNF 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 (WNV) 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, WNV is known long time ago, but it is since the last years of the twentieth 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?

Companion Animals as a Source of Viruses for Human Beings and Food Production Animals.

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Reperant, L A; Brown, I H; Haenen, O L; de Jong, M D; Osterhaus, A D M E; Papa, A; Rimstad, E; Valarcher, J-F; Kuiken, T

2016-07-01

Companion animals comprise a wide variety of species, including dogs, cats, horses, ferrets, guinea pigs, reptiles, birds and ornamental fish, as well as food production animal species, such as domestic pigs, kept as companion animals. Despite their prominent place in human society, little is known about the role of companion animals as sources of viruses for people and food production animals. Therefore, we reviewed the literature for accounts of infections of companion animals by zoonotic viruses and viruses of food production animals, and prioritized these viruses in terms of human health and economic importance. In total, 138 virus species reportedly capable of infecting companion animals were of concern for human and food production animal health: 59 of these viruses were infectious for human beings, 135 were infectious for food production mammals and birds, and 22 were infectious for food production fishes. Viruses of highest concern for human health included hantaviruses, Tahyna virus, rabies virus, West Nile virus, tick-borne encephalitis virus, Crimean-Congo haemorrhagic fever virus, Aichi virus, European bat lyssavirus, hepatitis E virus, cowpox virus, G5 rotavirus, influenza A virus and lymphocytic choriomeningitis virus. Viruses of highest concern for food production mammals and birds included bluetongue virus, African swine fever virus, foot-and-mouth disease virus, lumpy skin disease virus, Rift Valley fever virus, porcine circovirus, classical swine fever virus, equine herpesvirus 9, peste des petits ruminants virus and equine infectious anaemia virus. Viruses of highest concern for food production fishes included cyprinid herpesvirus 3 (koi herpesvirus), viral haemorrhagic septicaemia virus and infectious pancreatic necrosis virus. Of particular concern as sources of zoonotic or food production animal viruses were domestic carnivores, rodents and food production animals kept as companion animals. The current list of viruses provides an objective

Effectiveness and Cost Efficiency of Different Surveillance Components for Proving Freedom and Early Detection of Disease: Bluetongue Serotype 8 in Cattle as Case Study for Belgium, France and the Netherlands.

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Welby, S; van Schaik, G; Veldhuis, A; Brouwer-Middelesch, H; Peroz, C; Santman-Berends, I M; Fourichon, C; Wever, P; Van der Stede, Y

2017-12-01

Quick detection and recovery of country's freedom status remain a constant challenge in animal health surveillance. The efficacy and cost efficiency of different surveillance components in proving the absence of infection or (early) detection of bluetongue serotype 8 in cattle populations within different countries (the Netherlands, France, Belgium) using surveillance data from years 2006 and 2007 were investigated using an adapted scenario tree model approach. First, surveillance components (sentinel, yearly cross-sectional and passive clinical reporting) within each country were evaluated in terms of efficacy for substantiating freedom of infection. Yearly cross-sectional survey and passive clinical reporting performed well within each country with sensitivity of detection values ranging around 0.99. The sentinel component had a sensitivity of detection around 0.7. Secondly, how effective the components were for (early) detection of bluetongue serotype 8 and whether syndromic surveillance on reproductive performance, milk production and mortality data available from the Netherlands and Belgium could be of added value were evaluated. Epidemic curves were used to estimate the timeliness of detection. Sensitivity analysis revealed that expected within-herd prevalence and number of herds processed were the most influential parameters for proving freedom and early detection. Looking at the assumed direct costs, although total costs were low for sentinel and passive clinical surveillance components, passive clinical surveillance together with syndromic surveillance (based on reproductive performance data) turned out most cost-efficient for the detection of bluetongue serotype 8. To conclude, for emerging or re-emerging vectorborne disease that behaves such as bluetongue serotype 8, it is recommended to use passive clinical and syndromic surveillance as early detection systems for maximum cost efficiency and sensitivity. Once an infection is detected and eradicated

First molecular identification of the vertebrate hosts of Culicoides imicola in Europe and a review of its blood-feeding patterns worldwide: implications for the transmission of bluetongue disease and African horse sickness.

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Martínez-DE LA Puente, J; Navarro, J; Ferraguti, M; Soriguer, R; Figuerola, J

2017-12-01

Culicoides (Diptera: Ceratopogonidae) are vectors of pathogens that affect wildlife, livestock and, occasionally, humans. Culicoides imicola (Kieffer, 1913) is considered to be the main vector of the pathogens that cause bluetongue disease (BT) and African horse sickness (AHS) in southern Europe. The study of blood-feeding patterns in Culicoides is an essential step towards understanding the epidemiology of these pathogens. Molecular tools that increase the accuracy and sensitivity of traditional methods have been developed to identify the hosts of potential insect vectors. However, to the present group's knowledge, molecular studies that identify the hosts of C. imicola in Europe are lacking. The present study genetically characterizes the barcoding region of C. imicola trapped on farms in southern Spain and identifies its vertebrate hosts in the area. The report also reviews available information on the blood-feeding patterns of C. imicola worldwide. Culicoides imicola from Spain feed on blood of six mammals that include species known to be hosts of the BT and AHS viruses. This study provides evidence of the importance of livestock as sources of bloodmeals for C. imicola and the relevance of this species in the transmission of BT and AHS viruses in Europe. © 2017 The Royal Entomological Society.

Coinfections of Sudanese dairy cattle with bovine herpes virus 1, bovine viral diarrhea virus, bluetongue virus and bovine herpes virus 4 and their relation to reproductive disorders

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Amira M. Elhassan

2016-12-01

Reults: The meta-analysis of the data indicated high seroprevalence of coinfections with various combinations of these agents; only few animals were singly infected. An infection with BHV-1 was observed to be higher than the prevalence of associations between BHV-1 and the other three viral agents. Prevalence of seropositivities to coinfection with BHV-1/BTV; BHV-1/BVD; BHV-1/BTV/BVD were the highest while seropositivities prevalences that involved BHV-4 were much lower. The highest abortion rates were encountered in coinfections with BHV-1/BVD/BTV (31% and BHV-1/BVD/BTV/BHV-4 (30% while most infertility cases were noticed in coinfection with BHV-1/BVD/BTV (44% and BHV-1/BVD/BTV/BHV-4 (21%, and coinfections with the four viruses were encountered in most of the death after birth cases (25%. Overall mixed infections with BHV-1/BVD/BTV (34% and BHV-1/BVD/BTV/BHV-4 (22.5% were involved in the majority of reproductive problems studied. Conclusion: Mixed infections constitutes the vast majority of cases and are involved in the majority of reproductive disorders investigated. The high prevalence of seropositivity to all of the four viruses should call for an intervention strategy to reduce the impact of these viruses. [J Adv Vet Anim Res 2016; 3(4.000: 332-337

Culicoides variipennis (Diptera: Ceratopogonidae) complex in Virginia.

Science.gov (United States)

Schmidtmann, E T; Holbrook, F R; Day, E; Taylor, T; Tabachnick, W J

1998-09-01

Immature Culicoides variipennis (Coquillett) were sampled from aquatic habitats throughout Virginia, reared to adults, and examined by isozyme electrophoresis to assess their taxonomic status. Data from 22 counties showed that C. v. variipennis is widespread and common, the predominant taxon throughout Virginia, and genetically similar to C. v. variipennis in Maryland. Because C. v. variipennis is considered an inefficient vector of the bluetongue viruses, this observation is consistent with the low seroprevalence of bluetongue in indigenous livestock of the mid-Atlantic region. Culicoides v. sonorensis Wirth & Jones, considered to be the primary North American vector of the bluetongue viruses, was recovered in large numbers only from a wastewater lagoon at a dairy in southeastern Virginia, but also was detected at low levels in 6 other counties. Comparison of genetic distances and patterns of discriminating alleles among Virginia populations of C. v. variipennis and C. v. sonorensis showed that respective subspecies are genetically distinct and show no evidence of introgression, irrespective of geographic- and habitat-level sympatry. The persistence of a pure C. v. sonorensis population in a dairy wastewater lagoon may reflect physico-chemical factors that influence the distribution of immature C. variipennis complex populations. A better understanding of the distribution of the C. variipennis complex will benefit regionalization of U.S. exports of livestock and livestock germplasm to bluetongue-free countries.

Disruption of Specific RNA-RNA Interactions in a Double-Stranded RNA Virus Inhibits Genome Packaging and Virus Infectivity.

Science.gov (United States)

Fajardo, Teodoro; Sung, Po-Yu; Roy, Polly

2015-12-01

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

Characterization of Viral Communities of Biting Midges and Identification of Novel Thogotovirus Species and Rhabdovirus Genus

Directory of Open Access Journals (Sweden)

Sarah Temmam

2016-03-01

Full Text Available More than two thirds of emerging viruses are of zoonotic origin, and among them RNA viruses represent the majority. Ceratopogonidae (genus Culicoides are well-known vectors of several viruses responsible for epizooties (bluetongue, epizootic haemorrhagic disease, etc.. They are also vectors of the only known virus infecting humans: the Oropouche virus. Female midges usually feed on a variety of hosts, leading to possible transmission of emerging viruses from animals to humans. In this context, we report here the analysis of RNA viral communities of Senegalese biting midges using next-generation sequencing techniques as a preliminary step toward the identification of potential viral biohazards. Sequencing of the RNA virome of three pools of Culicoides revealed the presence of a significant diversity of viruses infecting plants, insects and mammals. Several novel viruses were detected, including a novel Thogotovirus species, related but genetically distant from previously described tick-borne thogotoviruses. Novel rhabdoviruses were also detected, possibly constituting a novel Rhabdoviridae genus, and putatively restricted to insects. Sequences related to the major viruses transmitted by Culicoides, i.e., African horse sickness, bluetongue and epizootic haemorrhagic disease viruses were also detected. This study highlights the interest in monitoring the emergence and circulation of zoonoses and epizooties using their arthropod vectors.

Characterization of Viral Communities of Biting Midges and Identification of Novel Thogotovirus Species and Rhabdovirus Genus

Science.gov (United States)

Temmam, Sarah; Monteil-Bouchard, Sonia; Robert, Catherine; Baudoin, Jean-Pierre; Sambou, Masse; Aubadie-Ladrix, Maxence; Labas, Noémie; Raoult, Didier; Mediannikov, Oleg; Desnues, Christelle

2016-01-01

More than two thirds of emerging viruses are of zoonotic origin, and among them RNA viruses represent the majority. Ceratopogonidae (genus Culicoides) are well-known vectors of several viruses responsible for epizooties (bluetongue, epizootic haemorrhagic disease, etc.). They are also vectors of the only known virus infecting humans: the Oropouche virus. Female midges usually feed on a variety of hosts, leading to possible transmission of emerging viruses from animals to humans. In this context, we report here the analysis of RNA viral communities of Senegalese biting midges using next-generation sequencing techniques as a preliminary step toward the identification of potential viral biohazards. Sequencing of the RNA virome of three pools of Culicoides revealed the presence of a significant diversity of viruses infecting plants, insects and mammals. Several novel viruses were detected, including a novel Thogotovirus species, related but genetically distant from previously described tick-borne thogotoviruses. Novel rhabdoviruses were also detected, possibly constituting a novel Rhabdoviridae genus, and putatively restricted to insects. Sequences related to the major viruses transmitted by Culicoides, i.e., African horse sickness, bluetongue and epizootic haemorrhagic disease viruses were also detected. This study highlights the interest in monitoring the emergence and circulation of zoonoses and epizooties using their arthropod vectors. PMID:26978389

Insects and disease in the 21st century : a wind of change

NARCIS (Netherlands)

Takken, W.

2008-01-01

In recent years, several other vectors have become world news: the sheep tick was discovered to be the vector of Lyme disease in 1980; the mosquito Culex pipiens began transmitting West Nile virus in North America in 1999; in August 2006, bluetongue virus was discovered in Belgium and the

A spatial simulation model for the dispersal of the bluetongue vector Culicoides brevitarsis in Australia.

Directory of Open Access Journals (Sweden)

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.

Field observations during the Bluetongue serotype 8 epidemic in 2006 II. Morbidity and mortality rate, case fatality and clinical recovery in sheep and cattle in the Netherlands

NARCIS (Netherlands)

Elbers, A.R.W.; Backx, A.; Mintiens, K.; Gerbier, G.; Staubach, C.; Hendrickx, G.; Spek, van der A.N.

2008-01-01

Data collected in the Netherlands during the Bluetongue serotype 8 (BTV-8) epidemic indicated that in outbreak cattle herds, predominantly dairy and nursing cows were clinically affected and not young stock, beef cattle, beef calves, or breeding animals. In outbreak sheep flocks, mainly ewes and ¿

[Arbovirus circulation in the Republic of Guinea].

Science.gov (United States)

Butenko, A M

1996-01-01

In 1978-1991 the USSR-Guinea Virological and Microbiological Laboratory functioned in Kindia, the Republic of Guinea. Arbovirus activity in this country was studied by a number of virologists and other specialists. Their personal contribution and achievements in this collaboration are reflected in the present paper. About 74,000 mosquitoes, 100,000 Ixodidae ticks, 1,500 wild birds, 2,700 bats, 106 monkeys, and 308 other mammals, 927 blood samples collected from febrile patients were examined in 1978-1989, using inoculation of new-born white mice. As a result of this work 127 strains of the following arboviruses were isolated: Chikungunia (1 strain), Dengue 2 (4), Saboya (7), Wesselsbron (1), Bunyamwera (4), M'Poko (5), Rift Valley Fever (6), CHF-Congo (9), Dugbe (22), Bhanja (6), Forecariah (2), Jos (26), Abadina (15), Kindia (2), Ark 6956 (1), Fomede (2), Bluetongue (9), Mossuril (2), AnK 6009 (1), and Kolente (2). Dengue 2, Wesselsbron, Bunyamwera, M'Poko, Kindia, Mossuril viruses were isolated from mosquitoes. Ixodidae ticks were sources for isolation of Chikungunia, Saboya, CCHF, Dugbe, Bhanja, Forecaciah, Jos, Abadina, Kindia, Ark 6956, Fomede, Bluetongue, and Kolente viruses. Saboya, RVF, Fomede, Kolente, AnK 6909 were isolated from bats (Chiroptera); Saboya, Abadina, and Bluetongue viruses from birds. One strain of Dugbe virus was originated from the brain of Cercopithecus patas. Bunyamwera and Abadina viruses were isolated from the blood of two febrile patients. Serological identification of many strains was kindly conducted at the Pasteur Institute, Dakar (J. P.Digoutte) and some at the YARU, USA (R. Shope). Kindia and Ark 6956 (Reovirus, gr. Palyam), Fomede (gr. Chobar Gorge), Forecariah (Bunyavirus, gr. Bhanja), Kolente (Rhabdovirus) were identified as an original type of Lagos bat virus. The results of seroepidemiological surveys are also presented.

The range of attraction for light traps catching Culicoides biting midges (Diptera: Ceratopogonidae)

DEFF Research Database (Denmark)

Kirkeby, Carsten; Græsbøll, Kaare; Stockmarr, Anders

2013-01-01

Background Culicoides are vectors of e.g. bluetongue virus and Schmallenberg virus in northern Europe. Light trapping is an important tool for detecting the presence and quantifying the abundance of vectors in the field. Until now, few studies have investigated the range of attraction of light tr...... light trap was estimated to be approximately 15.25 meters. The attraction towards light traps is different from the attraction to host animals and thus light trap catches may not represent the vector species and numbers attracted to hosts.......Background Culicoides are vectors of e.g. bluetongue virus and Schmallenberg virus in northern Europe. Light trapping is an important tool for detecting the presence and quantifying the abundance of vectors in the field. Until now, few studies have investigated the range of attraction of light...... traps. Methods Here we test a previously described mathematical model (Model I) and two novel models for the attraction of vectors to light traps (Model II and III). In Model I, Culicoides fly to the nearest trap from within a fixed range of attraction. In Model II Culicoides fly towards areas...

Epizootic of ovine congenital malformations associated with Schmallenberg virus infection.

Science.gov (United States)

van den Brom, R; Luttikholt, S J M; Lievaart-Peterson, K; Peperkamp, N H M T; Mars, M H; van der Poel, W H M; Vellema, P

2012-02-01

Epizootic outbreaks of congenital malformations in sheep are rare and have, to the best of our knowledge, never been reported before in Europe. This paper describes relevant preliminary findings from the first epizootic outbreak of ovine congenital malformations in the Netherlands. Between 25 November and 20 December 2011, congenital malformations in newborn lambs on sheep farms throughout the country were reported to the Animal Health Service in Deventer. Subsequently, small ruminant veterinary specialists visited these farms and collected relevant information from farmers by means of questionnaires. The deformities varied from mild to severe, and ewes were reported to have given birth to both normal and deformed lambs; both male and female lambs were affected. Most of the affected lambs were delivered at term. Besides malformed and normal lambs, dummy lambs, unable to suckle, were born also on these farms. None of the ewes had shown clinical signs during gestation or at parturition. Dystocia was common, because of the lambs' deformities. Lambs were submitted for post-mortem examination, and samples of brain tissue were collected for virus detection. The main macroscopic findings included arthrogryposis, torticollis, scoliosis and kyphosis, brachygnathia inferior, and mild-to-marked hypoplasia of the cerebrum, cerebellum and spinal cord. Preliminary data from the first ten affected farms suggest that nutritional deficiencies, intoxication, and genetic factors are not likely to have caused the malformations. Preliminary diagnostic analyses of precolostral serum samples excluded border disease virus, bovine viral diarrhoea virus, and bluetongue virus. In December 2011, samples of brain tissue from 54 lambs were sent to the Central Veterinary Institute of Wageningen University Research, Lelystad. Real-time PCR detected the presence of a virus, provisionally named the Schmallenberg virus, in brain tissue from 22 of the 54 lambs, which originated from seven of eight

Development and Characterization of a Multiplexed RT-PCR Species Specific Assay for Bovine and one for Porcine Foot-and-Mouth Disease Virus Rule-Out Supplemental Materials

Energy Technology Data Exchange (ETDEWEB)

Smith, S; Danganan, L; Tammero, L; Lenhoff, R; Naraghi-arani, P; Hindson, B

2007-08-06

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

Combining dispersion modelling with synoptic patterns to understand the wind-borne transport into the UK of the bluetongue disease vector.

Science.gov (United States)

Burgin, Laura; Ekström, Marie; Dessai, Suraje

2017-07-01

Bluetongue, an economically important animal disease, can be spread over long distances by carriage of insect vectors (Culicoides biting midges) on the wind. The weather conditions which influence the midge's flight are controlled by synoptic scale atmospheric circulations. A method is proposed that links wind-borne dispersion of the insects to synoptic circulation through the use of a dispersion model in combination with principal component analysis (PCA) and cluster analysis. We illustrate how to identify the main synoptic situations present during times of midge incursions into the UK from the European continent. A PCA was conducted on high-pass-filtered mean sea-level pressure data for a domain centred over north-west Europe from 2005 to 2007. A clustering algorithm applied to the PCA scores indicated the data should be divided into five classes for which averages were calculated, providing a classification of the main synoptic types present. Midge incursion events were found to mainly occur in two synoptic categories; 64.8% were associated with a pattern displaying a pressure gradient over the North Atlantic leading to moderate south-westerly flow over the UK and 17.9% of the events occurred when high pressure dominated the region leading to south-easterly or easterly winds. The winds indicated by the pressure maps generally compared well against observations from a surface station and analysis charts. This technique could be used to assess frequency and timings of incursions of virus into new areas on seasonal and decadal timescales, currently not possible with other dispersion or biological modelling methods.

The in vitro transcription and translation of bluetongue virus mRNA

International Nuclear Information System (INIS)

Van Dijk, A.A.

1985-12-01

The review of the literature on BTV and related viruses indicates that a detailed knowledge of the in vitro synthesis of BTV proteins is still lacking. A primary objective of this investigation was therefore to study this process. In order to achieve this objective, the in vitro transcription reaction also had to be investigated, since BTV mRNAs were required for the translational studies. Sulfur 35 and phosphorus 32 were used in this study. It was considered of particular importance to investigate factors that influence the efficiency of the in vitro transcription reaction, such as core concentration and incubation temperature. Knowledge of the in vitro translation of BTV mRNAs opens the possibility to obtain further detailed information on BTV as such, and BTV related aspects. The aim of the in vitro translation study of BTV was to identify all the proteins that are encoded by the 10 BTV mRNA species, and prove the viral origin of the non-structural proteins, as well as determinig the coding assignments of the 10 dsRNA genome segments. The last aspect of the study was to investigate whether in vitro synthesised NS2 differed from its in vivo synthesised counterpart with respect to phosphorylation and affinity for ssRNA, and to carry out experiments in order to identify the kinase phosphorylating NS2. The significance of the results obtained for each of these objectives is discussed in detail at the end of the relevent chapter. Finally, some concluding remarks are presented relating the overall findings of this investigation, as well as suggestions for future investigations

Innate Mammalian Immune Response to Culicoides Feeding

Science.gov (United States)

Hematophagous Culicoides spp. biting midges are of great agricultural importance as livestock and wildlife pests and as vectors of orbiviruses such as bluetongue, epizootic hemorrhagic disease, and African horse sickness viruses, as well as vesicular stomatitis, bovine ephemeral fever and Schmallenb...

Role of mammalian immune responses in vector-enhanced orbiviral transmission

Science.gov (United States)

Culicoides sonorensis biting midges are vectors of several emerging and re-emerging orbiviruses including bluetongue, epizootic hemorrhagic disease, and African horse sickness viruses. They feed primarily on domestic sheep and cattle, but opportunistically feed on a variety of wildlife and on humans...

Serologic survey for selected arboviruses and other potential pathogens in wildlife from Mexico.

Science.gov (United States)

Aguirre, A A; McLean, R G; Cook, R S; Quan, T J

1992-07-01

During 1988 and 1989, a serologic survey of wildlife was conducted in northeastern Mexico to determine the presence, prevalence, and distribution of arboviruses and other selected disease agents. Eighty mammal specimens were tested. Antibodies to vesicular stomatitis-Indiana, Venezuelan equine encephalitis-Mena II, Rio Grande virus, and vesicular stomatitis-New Jersey were detected predominantly in small mammals. Deer and mouflon (Ovis musimon) had antibodies to bluetongue and epizootic hemorrhagic disease. Two species had serologic evidence of recent exposure to Francisella tularensis. A white-tailed deer (Odocoileus virginianus) had antibodies to Anaplasma marginale. All specimens tested for antibodies against Yersinia pestis and Brucella abortus were negative. Sera from 315 birds were tested for antibody against five equine encephalitis viruses and six avian pathogens. During 1988, antibodies to Venezuelan equine encephalitis-Mena II, Venezuelan equine encephalitis-TC83, St. Louis encephalitis, eastern equine encephalitis, and western equine encephalitis were detected in birds of several species. Antibodies to Pasteurella multocida and Newcastle disease virus were also detected. Birds from five species presented antibodies to Mycoplasma meleagridis. Specimens tested for M. gallisepticum, M. synoviae, and Chlamydia psittaci were negative. To the best of our knowledge, this survey represents the first serologic evidence of bluetongue, Cache Valley virus, epizootic hemorrhagic disease, Jamestown Canyon virus, vesicular stomatitis-Indiana, vesicular stomatitis-New Jersey, Rio Grande virus, and tularemia reported among wildlife in Mexico.

Genetic variation in populations of Culicoides variipennis complex in the six New England states, U.S.A.

Science.gov (United States)

Holbrook, F R; Tabachnick, W J; Brady, R

1996-04-01

We investigated the identity and distribution of members of the Culicoides variipennis complex in the six New England states of the U.S.A., a region where bluetongue transmission has not been detected. Analyses of seven polymorphic isozyme-encoding loci showed that only C.v.variipennis, not considered to be a vector of the bluetongue viruses, was present. The populations of C.v.variipennis were significantly more hetero-zygous than C.v.sonorensis and C.v.occidentalis populations from similar studies in the state of California. Estimates of genetic diversity among populations of C.v.variipennis in New England were similar to C.v.sonorensis in the state of Colorado, but were significantly more genetically divergent than California populations of C.v.occidentalis. The impact of these findings on the status of New England as a possible bluetongue-free region for the purpose of international trade in ruminant livestock and their germplasm is discussed.

Development of a GeXP-multiplex PCR assay for the simultaneous detection and differentiation of six cattle viruses.

Directory of Open Access Journals (Sweden)

Qing Fan

Full Text Available Foot-and-mouth disease virus (FMDV, Bluetongue virus (BTV, Vesicular stomatitis Virus (VSV, Bovine viral diarrheal (BVDV, Bovine rotavirus (BRV, and Bovine herpesvirus 1 (IBRV are common cattle infectious viruses that cause a great economic loss every year in many parts of the world. A rapid and high-throughput GenomeLab Gene Expression Profiler (GeXP analyzer-based multiplex PCR assay was developed for the simultaneous detection and differentiation of these six cattle viruses. Six pairs of chimeric primers consisting of both the gene-specific primer and a universal primer were designed and used for amplification. Then capillary electrophoresis was used to separate the fluorescent labeled PCR products according to the amplicons size. The specificity of GeXP-multiplex PCR assay was examined with samples of the single template and mixed template of six viruses. The sensitivity was evaluated using the GeXP-multiplex PCR assay on serial 10-fold dilutions of ssRNAs obtained via in vitro transcription. To further evaluate the reliability, 305 clinical samples were tested by the GeXP-multiplex PCR assay. The results showed that the corresponding virus specific fragments of genes were amplified. The detection limit of the GeXP-multiplex PCR assay was 100 copies/μL in a mixed sample of ssRNAs containing target genes of six different cattle viruses, whereas the detection limit for the Gexp-mono PCR assay for a single target gene was 10 copies/μL. In detection of viruses in 305 clinical samples, the results of GeXP were consistent with simplex real-time PCR. Analysis of positive samples by sequencing demonstrated that the GeXP-multiplex PCR assay had no false positive samples of nonspecific amplification. In conclusion, this GeXP-multiplex PCR assay is a high throughput, specific, sensitive, rapid and simple method for the detection and differentiation of six cattle viruses. It is an effective tool that can be applied for the rapid differential diagnosis

Effect of vaccination with an inactivated vaccine on transplacental transmission of BTV-8 in mid term pregnant ewes and heifers

NARCIS (Netherlands)

Sluijs, van der M.T.W.; Schroer-Joosten, D.P.H.; Fid-Fourkour, A.; Vrijenhoek, M.; Debyser, I.; Gregg, D.A.; Dufe, D.M.; Moulin, V.; Moormann, R.J.M.; Smit, de A.J.

2012-01-01

The effect of vaccination with a commercial inactivated Bluetongue virus serotype 8 (BTV-8) vaccine on the ability of BTV-8 to cross the ruminant placenta was investigated in two experiments. Ten pregnant ewes (Experiment 1) or heifers (Experiment 2) were vaccinated according to the manufacturer's

Estimating the temporal and spatial risk of bluetongue related to the incursion of infected vectors into Switzerland

Directory of Open Access Journals (Sweden)

Griot C

2008-10-01

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

Development and Characterization of A Multiplexed RT-PCR Species Specific Assay for Bovine and one for Porcine Foot-and-Mouth Disease Virus Rule-Out

Energy Technology Data Exchange (ETDEWEB)

Smith, S M; Danganan, L; Tammero, L; Vitalis, B; Lenhoff, R; Naraghi-arani, P; Hindson, B

2007-08-06

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

Etiology, pathogenesis and future prospects for developing ...

African Journals Online (AJOL)

BTV serotypes are known to occur in Africa, Asia, South America, North America, Middle East, India, and Australia generally between latitudes 35°S and 50°N. It occurs around the Mediterranean in summer, subsiding when temperatures drop in winter. The replication phase of the bluetongue virus (BTV) infection cycle is ...

Sellers’ Revisited: A Big Data Reassessment of Historical Outbreaks of Bluetongue and African Horse Sickness due to the Long-Distance Wind Dispersion of Culicoides Midges

Directory of Open Access Journals (Sweden)

Peter A. Durr

2017-07-01

Full Text Available The possibility that outbreaks of bluetongue (BT and African horse sickness (AHS might occur via long-distance wind dispersion (LDWD of their insect vector (Culicoides spp. was proposed by R. F. Sellers in a series of papers published between 1977 and 1991. These investigated the role of LDWD by means of visual examination of the wind direction of synoptic weather charts. Based on the hypothesis that simple wind direction analysis, which does not allow for wind speed, might have led to spurious conclusions, we reanalyzed six of the outbreak scenarios described in Sellers’ papers. For this reanalysis, we used a custom-built Big Data application (“TAPPAS” which couples a user-friendly web-interface with an established atmospheric dispersal model (“HYSPLIT”, thus enabling more sophisticated modeling than was possible when Sellers undertook his analyzes. For the two AHS outbreaks, there was strong support from our reanalysis of the role of LDWD for that in Spain (1966, and to a lesser degree, for the outbreak in Cyprus (1960. However, for the BT outbreaks, the reassessments were more complex, and for one of these (western Turkey, 1977 we could discount LDWD as the means of direct introduction of the virus. By contrast, while the outbreak in Cyprus (1977 showed LDWD was a possible means of introduction, there is an apparent inconsistency in that the outbreaks were localized while the dispersion events covered much of the island. For Portugal (1956, LDWD from Morocco on the dates suggested by Sellers is very unlikely to have been the pathway for introduction, and for the detection of serotype 2 in Florida (1982, LDWD from Cuba would require an assumption of a lengthy survival time of the midges in the air column. Except for western Turkey, the BT reanalyses show the limitation of LDWD modeling when used by itself, and indicates the need to integrate susceptible host population distribution (and other covariate data into the modeling process

Sellers' Revisited: A Big Data Reassessment of Historical Outbreaks of Bluetongue and African Horse Sickness due to the Long-Distance Wind Dispersion of Culicoides Midges.

Science.gov (United States)

Durr, Peter A; Graham, Kerryne; van Klinken, Rieks D

2017-01-01

The possibility that outbreaks of bluetongue (BT) and African horse sickness (AHS) might occur via long-distance wind dispersion (LDWD) of their insect vector ( Culicoides spp.) was proposed by R. F. Sellers in a series of papers published between 1977 and 1991. These investigated the role of LDWD by means of visual examination of the wind direction of synoptic weather charts. Based on the hypothesis that simple wind direction analysis, which does not allow for wind speed, might have led to spurious conclusions, we reanalyzed six of the outbreak scenarios described in Sellers' papers. For this reanalysis, we used a custom-built Big Data application (" TAPPAS ") which couples a user-friendly web-interface with an established atmospheric dispersal model (" HYSPLIT "), thus enabling more sophisticated modeling than was possible when Sellers undertook his analyzes. For the two AHS outbreaks, there was strong support from our reanalysis of the role of LDWD for that in Spain (1966), and to a lesser degree, for the outbreak in Cyprus (1960). However, for the BT outbreaks, the reassessments were more complex, and for one of these (western Turkey, 1977) we could discount LDWD as the means of direct introduction of the virus. By contrast, while the outbreak in Cyprus (1977) showed LDWD was a possible means of introduction, there is an apparent inconsistency in that the outbreaks were localized while the dispersion events covered much of the island. For Portugal (1956), LDWD from Morocco on the dates suggested by Sellers is very unlikely to have been the pathway for introduction, and for the detection of serotype 2 in Florida (1982), LDWD from Cuba would require an assumption of a lengthy survival time of the midges in the air column. Except for western Turkey, the BT reanalyses show the limitation of LDWD modeling when used by itself, and indicates the need to integrate susceptible host population distribution (and other covariate) data into the modeling process. A further

Serosurvey for selected pathogens in Iberian roe deer

OpenAIRE

Boadella, Mariana; Carta, Tania; Oleaga, ?lvaro; Pajares, Gerardo; Mu?oz, Marta; Gort?zar, Christian

2010-01-01

Abstract Background The roe deer is the most abundant and widespread wild Eurasian cervid. Its populations are expanding and increasingly in contact with livestock. This may affect the distribution of infectious diseases shared with other wild and domestic ungulates. Methods We investigated the antibody seroprevalence against Pestivirus, Herpesvirus, Bluetongue (BT) virus, M. avium paratuberculosis (MAP), and Brucella sp. in 519 roe deer from different regions in Spain, south-western Europe. ...

Modelling the distributions and spatial coincidence of bluetongue vectors Culicoides imicola and the Culicoides obsoletus group throughout the Iberian peninsula.

Science.gov (United States)

Calvete, C; Estrada, R; Miranda, M A; Borrás, D; Calvo, J H; Lucientes, J

2008-06-01

Data obtained by a Spanish national surveillance programme in 2005 were used to develop climatic models for predictions of the distribution of the bluetongue virus (BTV) vectors Culicoides imicola Kieffer (Diptera: Ceratopogonidae) and the Culicoides obsoletus group Meigen throughout the Iberian peninsula. Models were generated using logistic regression to predict the probability of species occurrence at an 8-km spatial resolution. Predictor variables included the annual mean values and seasonalities of a remotely sensed normalized difference vegetation index (NDVI), a sun index, interpolated precipitation and temperature. Using an information-theoretic paradigm based on Akaike's criterion, a set of best models accounting for 95% of model selection certainty were selected and used to generate an average predictive model for each vector. The predictive performances (i.e. the discrimination capacity and calibration) of the average models were evaluated by both internal and external validation. External validation was achieved by comparing average model predictions with surveillance programme data obtained in 2004 and 2006. The discriminatory capacity of both models was found to be reasonably high. The estimated areas under the receiver operating characteristic (ROC) curve (AUC) were 0.78 and 0.70 for the C. imicola and C. obsoletus group models, respectively, in external validation, and 0.81 and 0.75, respectively, in internal validation. The predictions of both models were in close agreement with the observed distribution patterns of both vectors. Both models, however, showed a systematic bias in their predicted probability of occurrence: observed occurrence was systematically overestimated for C. imicola and underestimated for the C. obsoletus group. Average models were used to determine the areas of spatial coincidence of the two vectors. Although their spatial distributions were highly complementary, areas of spatial coincidence were identified, mainly in

How does increasing immunity change spread kernel parameters in subsequent outbreaks? – A simulation study on Bluetongue Virus

DEFF Research Database (Denmark)

Græsbøll, Kaare; Bødker, Rene; Enøe, Claes

Modelling the spatial spread of vector borne diseases, one may choose methods ranging from statistic to process oriented. One often used statistic tool is the empirical spread kernel. An empiric spread kernel fitted to outbreak data provides hints on the spread mechanisms, and may provide a good...... estimate on how future epidemics could proceed under similar conditions. However, a number of variables influence the spread of vector borne diseases. If one of these changes significantly after an outbreak, it needs to be incorporated into the model to improve the prediction on future outbreaks. Examples...... 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...

Optimal vaccination strategies against vector-borne diseases

DEFF Research Database (Denmark)

Græsbøll, Kaare; Enøe, Claes; Bødker, Rene

2014-01-01

Using a process oriented semi-agent based model, we simulated the spread of Bluetongue virus by Culicoides, biting midges, between cattle in Denmark. We evaluated the minimum vaccination cover and minimum cost for eight different preventive vaccination strategies in Denmark. The simulation model ...... results when index cases were in the vaccinated areas. However, given that the long-range spread of midge borne disease is still poorly quantified, more robust national vaccination schemes seem preferable....

Field evaluation of the efficacy and safety of a deltamethrin pour on formulation (Butox® 7.5 mg/ml pour on) for the control of Culicoides midges in sheep

OpenAIRE

Weiher, Wiebke

2014-01-01

Culicoides spp. (Diptera: Ceratopogonidae) are the main vectors of Bluetongue and Schmallenberg virus disease, which are infectious diseases of ruminants. Recently, both viral diseases occurred for the first time in Germany and caused substantial suffering and large economic losses, primarily in sheep flocks. None of the currently available insecticides is registered to control infestations with Culicoides midges in ruminants. This study aimed to assess the safety and efficacy of a pour on fo...

The economic impact of Bluetongue and other orbiviruses in sub-Saharan Africa, with special reference to Southern Africa.

Science.gov (United States)

Grewar, John Duncan

2016-09-30

Bluetongue (BT) and African horse sickness (AHS) are considered the most important orbiviral diseases in Southern Africans countries. The general endemic status makes these diseases challenging to be quanti ed in terms of their economic impact. Using country reported data from BT and AHS outbreaks and cases, as well as international trade data, the economic impact of BT and AHS is evaluated on local, regional, and global scales. Local scale impact in the Southern African region is underestimated as shown by the underreporting of BT and AHS. Exceptions occur during epidemic cycles of the diseases and when the diseases impact regional animal movement and global trade, as in the case of AHS in South Africa. While BT is not directly implicated as a signi cant non-tari barrier for regional movement, there are unspeci ed clauses in import permits which refer to the 'OIE listed diseases' and the freedom thereof includes endemic diseases like BT. African horse sickness has a much more tangible regional and global economic impact because of movement restrictions within AHS control zones in South Africa and through international movement of horses from this country.

Geographic range of vector-borne infections and their vectors: the role of African wildlife.

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van Vuuren, M; Penzhorn, B L

2015-04-01

The role of African wildlife in the occurrence of vector-borne infections in domestic animals has gained renewed interest as emerging and re-emerging infections occur worldwide at an increasing rate. In Africa, biodiversity conservation and the expansion of livestock production have increased the risk of transmitting vector-borne infections between wildlife and livestock. The indigenous African pathogens with transboundary potential, such as Rift Valley fever virus, African horse sickness virus, bluetongue virus, lumpy skin disease virus, African swine fever virus, and blood-borne parasites have received the most attention. There is no evidence for persistent vector-borne viral infections in African wildlife. For some viral infections, wildlife may act as a reservoir through the inter-epidemic circulation of viruses with mild or subclinical manifestations. Wildlife may also act as introductory or transporting hosts when moved to new regions, e.g. for lumpy skin disease virus, Rift Valley fever virus and West Nile virus. Wildlife may also act as amplifying hosts when exposed to viruses in the early part of the warm season when vectors are active, with spillover to domestic animals later in the season, e.g. with bluetongue and African horse sickness. Some tick species found on domestic animals are more abundant on wildlife hosts; some depend on wildlife hosts to complete their life cycle. Since the endemic stability of a disease depends on a sufficiently large tick population to ensure that domestic animals become infected at an early age, the presence of wildlife hosts that augment tick numbers may be beneficial. Many wild ungulate species are reservoirs of Anaplasma spp., while the role of wildlife in the epidemiology of heartwater (Ehrlichia ruminantium infection) has not been elucidated. Wild ungulates are not usually reservoirs of piroplasms that affect livestock; however, there are two exceptions: zebra, which are reservoirs of Babesia caballi and Theileria

A Comparison of Dynamics in Two Models for the Spread of a Vector-Borne Disease

DEFF Research Database (Denmark)

Græsbøll, Kaare; Sumner, T.; Enøe, Claes

2016-01-01

In 2007, bluetongue virus (BTV) was introduced to both Denmark (DK) and the United Kingdom (UK). For this reason, simulation models were built to predict scenarios for future incursions. The DK and UK models have a common description of within-herd dynamics, but differ greatly in their descriptio...... sensitivity to the level of vaccine uptake and has lower variability compared with a kernel-based model. However, a model using a transmission kernel requires less detailed data and is often faster....

Agricultural production - Phase 2. Indonesia. Isolation of arboviruses, their identification and the identification of their culicoides vectors in Indonesia

International Nuclear Information System (INIS)

Mellor, P.S.

1991-01-01

The aims of the two-week mission were to provide assistance in studies to determine the incidence and importance of arbovirus infection in ruminants in Indonesia, specifically to help with identification of the vectors tat transmit bluetongue and related arbovirus infections, and to develop work plans for future studies under the project. The report contains detailed information on handling systems for Culicoides species, on identification of Culicoides to be used for viral isolation and on the isolation of virus from Culicoides

Modelling the effects of past and future climate on the risk of bluetongue emergence in Europe

Science.gov (United States)

Guis, Helene; Caminade, Cyril; Calvete, Carlos; Morse, Andrew P.; Tran, Annelise; Baylis, Matthew

2012-01-01

Vector-borne diseases are among those most sensitive to climate because the ecology of vectors and the development rate of pathogens within them are highly dependent on environmental conditions. Bluetongue (BT), a recently emerged arboviral disease of ruminants in Europe, is often cited as an illustration of climate's impact on disease emergence, although no study has yet tested this association. Here, we develop a framework to quantitatively evaluate the effects of climate on BT's emergence in Europe by integrating high-resolution climate observations and model simulations within a mechanistic model of BT transmission risk. We demonstrate that a climate-driven model explains, in both space and time, many aspects of BT's recent emergence and spread, including the 2006 BT outbreak in northwest Europe which occurred in the year of highest projected risk since at least 1960. Furthermore, the model provides mechanistic insight into BT's emergence, suggesting that the drivers of emergence across Europe differ between the South and the North. Driven by simulated future climate from an ensemble of 11 regional climate models, the model projects increase in the future risk of BT emergence across most of Europe with uncertainty in rate but not in trend. The framework described here is adaptable and applicable to other diseases, where the link between climate and disease transmission risk can be quantified, permitting the evaluation of scale and uncertainty in climate change's impact on the future of such diseases. PMID:21697167

Ebola Virus and Marburg Virus

Science.gov (United States)

Ebola virus and Marburg virus Overview Ebola virus and Marburg virus are related viruses that cause hemorrhagic fevers — illnesses marked by severe bleeding (hemorrhage), organ failure and, in many ...

Virus-Vectored Influenza Virus Vaccines

Science.gov (United States)

Tripp, Ralph A.; Tompkins, S. Mark

2014-01-01

Despite the availability of an inactivated vaccine that has been licensed for >50 years, the influenza virus continues to cause morbidity and mortality worldwide. Constant evolution of circulating influenza virus strains and the emergence of new strains diminishes the effectiveness of annual vaccines that rely on a match with circulating influenza strains. Thus, there is a continued need for new, efficacious vaccines conferring cross-clade protection to avoid the need for biannual reformulation of seasonal influenza vaccines. Recombinant virus-vectored vaccines are an appealing alternative to classical inactivated vaccines because virus vectors enable native expression of influenza antigens, even from virulent influenza viruses, while expressed in the context of the vector that can improve immunogenicity. In addition, a vectored vaccine often enables delivery of the vaccine to sites of inductive immunity such as the respiratory tract enabling protection from influenza virus infection. Moreover, the ability to readily manipulate virus vectors to produce novel influenza vaccines may provide the quickest path toward a universal vaccine protecting against all influenza viruses. This review will discuss experimental virus-vectored vaccines for use in humans, comparing them to licensed vaccines and the hurdles faced for licensure of these next-generation influenza virus vaccines. PMID:25105278

Information management and ante-mortem inspection procedures for the emerging diseases control: Experiences acquired in the epidemiological surveillance of bluetongue and lumpy skin disease.

Science.gov (United States)

Corradini, Alessandra; Trevisani, Marcello; Dosa, Geremia; Padovani, Anna

2018-03-31

The spread of exotic, emerging and reemerging diseases, has become, in the last years, one of the most important threats to the animal productions and public health, representing a new challenge for the European Community. In a global-market framework, where trade and contacts between countries are simplified, effective and well-developed surveillance systems are necessary. Multiple factors are, in fact, associated with the emergence of new, known or exotic diseases in this new economic panorama and for these reasons controls on animal imports, traceability and timeliness detection of infected animals should be considered the basis of a sound surveillance. In this work, we focused our attention on the management of Bluetongue and on the risk of introduction of the Lumpy Skin Disease in Italy, in order to describe the national and European surveillance systems for these diseases. In particular, we underlined the crucial role of information that reach the Official Veterinarian at the slaughterhouse concerning the epidemiological situation of the sending countries. Information that are important for the management of the ante-mortem inspection and for increasing the awareness of the Veterinary Inspectors of their role in the surveillance.

Information management and ante-mortem inspection procedures for the emerging diseases control: Experiences acquired in the epidemiological surveillance of bluetongue and lumpy skin disease

Directory of Open Access Journals (Sweden)

Alessandra Corradini

2018-03-01

Full Text Available The spread of exotic, emerging and reemerging diseases, has become, in the last years, one of the most important threats to the animal productions and public health, representing a new challenge for the European Community. In a global-market framework, where trade and contacts between countries are simplified, effective and well-developed surveillance systems are necessary. Multiple factors are, in fact, associated with the emergence of new, known or exotic diseases in this new economic panorama and for these reasons controls on animal imports, traceability and timeliness detection of infected animals should be considered the basis of a sound surveillance. In this work, we focused our attention on the management of Bluetongue and on the risk of introduction of the Lumpy Skin Disease in Italy, in order to describe the national and European surveillance systems for these diseases. In particular, we underlined the crucial role of information that reach the Official Veterinarian at the slaughterhouse concerning the epidemiological situation of the sending countries. Information that are important for the management of the ante-mortem inspection and for increasing the awareness of the Veterinary Inspectors of their role in the surveillance.

Detection and analysis of six lizard adenoviruses by consensus primer PCR provides further evidence of a reptilian origin for the atadenoviruses.

Science.gov (United States)

Wellehan, James F X; Johnson, April J; Harrach, Balázs; Benkö, Mária; Pessier, Allan P; Johnson, Calvin M; Garner, Michael M; Childress, April; Jacobson, Elliott R

2004-12-01

A consensus nested-PCR method was designed for investigation of the DNA polymerase gene of adenoviruses. Gene fragments were amplified and sequenced from six novel adenoviruses from seven lizard species, including four species from which adenoviruses had not previously been reported. Host species included Gila monster, leopard gecko, fat-tail gecko, blue-tongued skink, Tokay gecko, bearded dragon, and mountain chameleon. This is the first sequence information from lizard adenoviruses. Phylogenetic analysis indicated that these viruses belong to the genus Atadenovirus, supporting the reptilian origin of atadenoviruses. This PCR method may be useful for obtaining templates for initial sequencing of novel adenoviruses.

Viral diseases of northern ungulates

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K. Frölich

2000-03-01

Full Text Available This paper describes viral diseases reported in northern ungulates and those that are a potential threat to these species. The following diseases are discussed: bovine viral diarrhoea/mucosal disease (BVD/MD, alphaherpesvirus infections, malignant catarrhal fever (MCF, poxvirus infections, parainfluenza type 3 virus infection, Alvsborg disease, foot-and-mouth disease, epizootic haemorrhage disease of deer and bluetongue disease, rabies, respiratory syncytial virus infection, adenovirus infection, hog-cholera, Aujeszky's disease and equine herpesvirus infections. There are no significant differences in antibody prevalence to BVDV among deer in habitats with high, intermediate and low density of cattle. In addition, sequence analysis from the BVDV isolated from roe deer (Capreolus capreolus showed that this strain was unique within BVDV group I. Distinct BVDV strains might circulate in free-ranging roe deer populations in Germany and virus transmission may be independent of domestic livestock. Similar results have been obtained in a serological survey of alpha-herpesviruses in deer in Germany. Malignant catarrhal fever was studied in fallow deer (Cervus dama in Germany: the seroprevalence and positive PCR results detected in sheep originating from the same area as the antibody-positive deer might indicate that sheep are the main reservoir animals. Contagious ecthyma (CE is a common disease in domestic sheep and goats caused by the orf virus. CE has been diagnosed in Rocky Mountain bighorn sheep (Ovis canadensis, mountain goats (Oreamnos americanus, Dall sheep (Ovis dalli, chamois (Rupkapra rupi-capra, muskox {Ovibos moschatus and reindeer (Rangifer tarandus. Most parainfluenza type 3 virus infections are mild or clinically undetectable. Serological surveys in wildlife have been successfully conducted in many species. In 1985, a new disease was identified in Swedish moose (Alces alces, designated as Alvsborg disease. This wasting syndrome probably

Sensitive detection of novel Indian isolate of BTV 21 using ns1 gene based real-time PCR assay

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Gaya Prasad

2013-06-01

Full Text Available Aim: The study was conducted to develop ns1 gene based sensitive real-time RT-PCR assay for diagnosis of India isolates of bluetongue virus (BTV. Materials and Methods: The BTV serotype 21 isolate (KMNO7 was isolated from Andhra Pradesh and propagated in BHK-21 cell line in our laboratory. The Nucleic acid (dsRNA of virus was extracted using Trizol method and cDNA was prepared using a standard protocol. The cDNA was allowed to ns1 gene based group specific PCR to confirm the isolate as BTV. The viral RNA was diluted 10 folds and the detection limit of ns1 gene based RT-PCR was determined. Finally the tenfold diluted viral RNA was subjected to real-time RT-PCR using ns1 gene primer and Taq man probe to standardized the reaction and determine the detection limit. Results: The ns1 gene based group specific PCR showed a single 366bp amplicon in agarose gel electrophoresis confirmed the sample as BTV. The ns1 gene RT-PCR using tenfold diluted viral RNA showed the detection limit of 70.0 fg in 1%agarose gel electrophoresis. The ns1 gene based real time RT-PCR was successfully standardized and the detection limit was found to be 7.0 fg. Conclusion: The ns1 gene based real-time RT-PCR was successfully standardized and it was found to be 10 times more sensitive than conventional RT-PCR. Key words: bluetongue, BTV21, RT-PCR, Real time RT-PCR, ns1 gene [Vet World 2013; 6(8.000: 554-557

Infectious disease survey of gemsbok in New Mexico

Science.gov (United States)

Bender, L.C.; Li, H.; Thompson, B.C.; Morrow, P.C.; Valdez, R.

2003-01-01

Exotic wildlife can introduce new diseases or act as reservoirs of endemic diseases. On White Sands Missile Range, New Mexico (USA), significant declines in populations of native ungulates generally correspond to increases in range and population density of the exotic gemsbok (Oryx gazella gazella), introduced beginning in 1969. We surveyed gemsbok in 2001 for exposure to a variety of diseases potentially important for native ungulates. High seroprevalence was found for malignant catarrhal fever virus (49 [98%] of 50 sera; 43 [96%] of 45 plasma samples), bluetongue virus (48 [96%] of 50), bovine respiratory syncytial virus (33 [66%] of 50), and parainfluenza-3 virus (10 [20%] of 50). Low numbers of Nematodirus spp. eggs in a few individuals were the only parasites detected in gemsbok. Exposure to the above diseases in gemsbok is of interest to managers because of potential implications for recovery of desert bighorn sheep (Ovis canadensis mexicana) and desert mule deer (Odocoileus hemionus crooki) in the White Sands area because each has been implicated in mortality in these species either in the White Sands area or elsewhere in the western/southwestern United States. ?? Wildlife Disease Association 2003.

Culicoides midges (Diptera: Ceratopogonidae as vectors of orbiviruses in Slovakia

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Adela Sarvašová

2014-09-01

Full Text Available In recent years, rapid spread of Culicoides-borne pathogens such as bluetongue (BT and Schmallenberg viruses have been reported in Europe. In this study we examined the Culicoides populations in farms with wild and domestic ruminants in Eastern Slovakia with the aim to confirm the presence of biting midges serving as potential vectors of important pathogens. The main vector complexes were the Obsoletus complex (54%; n=4,209 and the Pulicaris complex (23%; n=1,796. To estimate the relative abundance of the cryptic species of the Obsoletus complex (Culicoides obsoletus, Culicoides scoticus and Culicoides montanus, we performed the multiplex polymerase chain reaction (PCR based on ITS-2 and ITS-1 segments, on 125 midges randomly sampled. The relative abundance of C. obsoletus ranged from 5.26% in the farm with wild ruminants to 85.71% in another farm with cattle and sheep. A total of 112 pools of parous and gravid females belonging to the Obsoletus and Pulicaris complexes were tested for virus detection by the real-time reverse transcription polymerase chain reaction (RT-PCR for BT virus, as well as for the Epizootic Hemorrhagic Disease Virus (EHDV, with negative results.

Nairobi sheep disease virus/Ganjam virus.

Science.gov (United States)

M D, Baron; B, Holzer

2015-08-01

Nairobi sheep disease virus (NSDV) is a tick-borne virus which causes a severe disease in sheep and goats, and has been responsible for several outbreaks of disease in East Africa. The virus is also found in the Indian subcontinent, where it is known as Ganjam virus. The virus only spreads through the feeding of competent infected ticks, and is therefore limited in its geographic distribution by the distribution of those ticks, Rhipicephalus appendiculata in Africa and Haemaphysalis intermedia in India. Animals bred in endemic areas do not normally develop disease, and the impact is therefore primarily on animals being moved for trade or breeding purposes. The disease caused by NSDV has similarities to several other ruminant diseases, and laboratory diagnosis is necessary for confirmation. There are published methods for diagnosis based on polymerase chain reaction, for virus growth in cell culture and for other simple diagnostic tests, though none has been commercialised. There is no established vaccine against NSDV, although cell-culture attenuated strains have been developed which show promise and could be put into field trials if it were deemed necessary. The virus is closely related to Crimean-Congo haemorrhagic fever virus, and studies on NSDV may therefore be useful in understanding this important human pathogen.

Culicoides Species Communities Associated with Wild Ruminant Ecosystems in Spain: Tracking the Way to Determine Potential Bridge Vectors for Arboviruses.

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Sandra Talavera

Full Text Available The genus Culicoides Latreille 1809 is a well-known vector for protozoa, filarial worms and, above all, numerous viruses. The Bluetongue virus (BTV and the recently emerged Schmallenberg virus (SBV are responsible for important infectious, non-contagious, insect-borne viral diseases found in domestic ruminants and transmitted by Culicoides spp. Both of these diseases have been detected in wild ruminants, but their role as reservoirs during the vector-free season still remains relatively unknown. In fact, we tend to ignore the possibility of wild ruminants acting as a source of disease (BTV, SBV and permitting its reintroduction to domestic ruminants during the following vector season. In this context, a knowledge of the composition of the Culicoides species communities that inhabit areas where there are wild ruminants is of major importance as the presence of a vector species is a prerequisite for disease transmission. In this study, samplings were conducted in areas inhabited by different wild ruminant species; samples were taken in both 2009 and 2010, on a monthly basis, during the peak season for midge activity (in summer and autumn. A total of 102,693 specimens of 40 different species of the genus Culicoides were trapped; these included major BTV and SBV vector species. The most abundant vector species were C. imicola and species of the Obsoletus group, which represented 15% and 11% of total numbers of specimens, respectively. At the local scale, the presence of major BTV and SBV vector species in areas with wild ruminants coincided with that of the nearest sentinel farms included in the Spanish Bluetongue Entomological Surveillance Programme, although their relative abundance varied. The data suggest that such species do not exhibit strong host specificity towards either domestic or wild ruminants and that they could consequently play a prominent role as bridge vectors for different pathogens between both types of ruminants. This finding

DIAGNOSTICS OF VIRUS PHYTOPATHOGENS FRUIT TREE PLUM POX VIRUS, PRUNUS NECROTIC RINGSPOT VIRUS AND PRUNUS DWARF VIRUS BY BIOLOGICAL AND MOLECULAR DIAGNOSTICS

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Július Rozák

2013-02-01

Full Text Available The aim of this study was to determine the incidence of viral phytopathogen Plum pox virus, Prunus necrotic ringspot virus and Prunus dwarf virus in selected localities of Slovakia and diagnose them using a molecular and biological methods. Forty samples of fruit trees of the genus Prunus, twenty samples from intensive plantings and twenty samples from wild subject were analysed. Biological diagnostic by using biological indicators Prunus persica cv. GF 305, Prunus serrulata cv. Schirofugen and molecular diagnostic by mRT-PCR were applied. Five samples with Plum pox virus were infected. The two samples positive for Prunus necrotic ringspot virus and one sample for Prunus dwarf virus were confirmed. The two samples were found to be infected with two viruses Prunus necrotic ringspot virus and Prunus dwarf virus. This work focuses on two techniques, their application to the diagnosis of stone fruit viruses and their routinely used for sanitary and certification programmes.

Spatial and Temporal Evolution of Bluetongue Virus in Wild Ruminants, Spain

OpenAIRE

Ruiz-Fons, Francisco; Reyes-García, Álvaro R.; Alcaide, Vicente; Gortázar, Christian

2008-01-01

This study was supported by Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria–Ministerio de Educación (ACF2006-00001) and Comisión Interministerial de Ciencia y Tecnología–Ministerio de Educación (AGL2005-07401); and grants and contracts from Principado de Asturias Castilla–La Mancha, Médica Mutua Madrileña, Ministerio de Agricultura Pesca y Alimentación, and Grupo Santander–Fundación Marcelino Botín.

Oncogenic Viruses and Breast Cancer: Mouse Mammary Tumor Virus (MMTV, Bovine Leukemia Virus (BLV, Human Papilloma Virus (HPV, and Epstein–Barr Virus (EBV

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James S. Lawson

2018-01-01

Full Text Available BackgroundAlthough the risk factors for breast cancer are well established, namely female gender, early menarche and late menopause plus the protective influence of early pregnancy, the underlying causes of breast cancer remain unknown. The development of substantial recent evidence indicates that a handful of viruses may have a role in breast cancer. These viruses are mouse mammary tumor virus (MMTV, bovine leukemia virus (BLV, human papilloma viruses (HPVs, and Epstein–Barr virus (EBV-also known as human herpes virus type 4. Each of these viruses has documented oncogenic potential. The aim of this review is to inform the scientific and general community about this recent evidence.The evidenceMMTV and human breast cancer—the evidence is detailed and comprehensive but cannot be regarded as conclusive. BLV and human breast cancer—the evidence is limited. However, in view of the emerging information about BLV in human breast cancer, it is prudent to encourage the elimination of BLV in cattle, particularly in the dairy industry. HPVs and breast cancer—the evidence is substantial but not conclusive. The availability of effective preventive vaccines is a major advantage and their use should be encouraged. EBV and breast cancer—the evidence is also substantial but not conclusive. Currently, there are no practical means of either prevention or treatment. Although there is evidence of genetic predisposition, and cancer in general is a culmination of events, there is no evidence that inherited genetic traits are causal.ConclusionThe influence of oncogenic viruses is currently the major plausible hypothesis for a direct cause of human breast cancer.

Oncogenic Viruses and Breast Cancer: Mouse Mammary Tumor Virus (MMTV), Bovine Leukemia Virus (BLV), Human Papilloma Virus (HPV), and Epstein-Barr Virus (EBV).

Science.gov (United States)

Lawson, James S; Salmons, Brian; Glenn, Wendy K

2018-01-01

Although the risk factors for breast cancer are well established, namely female gender, early menarche and late menopause plus the protective influence of early pregnancy, the underlying causes of breast cancer remain unknown. The development of substantial recent evidence indicates that a handful of viruses may have a role in breast cancer. These viruses are mouse mammary tumor virus (MMTV), bovine leukemia virus (BLV), human papilloma viruses (HPVs), and Epstein-Barr virus (EBV-also known as human herpes virus type 4). Each of these viruses has documented oncogenic potential. The aim of this review is to inform the scientific and general community about this recent evidence. MMTV and human breast cancer-the evidence is detailed and comprehensive but cannot be regarded as conclusive. BLV and human breast cancer-the evidence is limited. However, in view of the emerging information about BLV in human breast cancer, it is prudent to encourage the elimination of BLV in cattle, particularly in the dairy industry. HPVs and breast cancer-the evidence is substantial but not conclusive. The availability of effective preventive vaccines is a major advantage and their use should be encouraged. EBV and breast cancer-the evidence is also substantial but not conclusive. Currently, there are no practical means of either prevention or treatment. Although there is evidence of genetic predisposition, and cancer in general is a culmination of events, there is no evidence that inherited genetic traits are causal. The influence of oncogenic viruses is currently the major plausible hypothesis for a direct cause of human breast cancer.

A transversal study on antibodies against selected pathogens in dromedary camels in the Canary Islands, Spain.

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Mentaberre, Gregorio; Gutiérrez, Carlos; Rodríguez, Noé F; Joseph, Sunitha; González-Barrio, David; Cabezón, Oscar; de la Fuente, José; Gortazar, Christian; Boadella, Mariana

2013-12-27

The Canary Islands contain the most important dromedary camel (Camelus dromedarius) population in the European Union and are the main export point of dromedaries to continental Europe and Latin America. We investigated the presence of antibodies against relevant disease agents in 100 Canarian camel sera. Selected blood samples of the same animals were also tested by PCR. Sera were tested for antibodies against Bluetongue virus (BTV; 0%), Bovine Viral Diarrhoea virus (BVDV; 0%), Camelpox virus (CPV; 8% by serum neutralization, 16% by ELISA), Peste des Petits Ruminants virus (PPRV, 0%), Rift Valley Fever virus (RVFV; 0%) and West Nile Fever virus (WNV; 3%), the bacterial pathogens Anaplasma sp. (3%), Brucella sp. (1%), Coxiella burnetii (19%), Mycobacterium avium paratuberculosis (MAP; 22%), Mycobacterium tuberculosis complex (MTC; 10%) and Rickettsia sp. (83%), and the parasites Toxoplasma gondii (36%) and Neospora caninum (86%). The most remarkable findings were the detection of antibodies against CPV and the high antibody prevalence against C. burnetii, Rickettsia sp., T. gondii and N. caninum. By PCR, we found no C. burnetii, N. caninum and Anaplasma sp. DNA in the tested samples. However, Rickettsia sp. DNA was detected in six antibody positive tested samples. These results should be taken into consideration in order to implement adequate control measures and avoid a potential dissemination of infections to other territories. Copyright © 2013 Elsevier B.V. All rights reserved.

Evolutionary relationship of alfalfa mosaic virus with cucumber mosaic virus and brome mosaic virus

OpenAIRE

Savithri, HS; Murthy, MRN

1983-01-01

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...

Comparative analysis of chrysanthemum transcriptome in response to three RNA viruses: Cucumber mosaic virus, Tomato spotted wilt virus and Potato virus X.

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Choi, Hoseong; Jo, Yeonhwa; Lian, Sen; Jo, Kyoung-Min; Chu, Hyosub; Yoon, Ju-Yeon; Choi, Seung-Kook; Kim, Kook-Hyung; Cho, Won Kyong

2015-06-01

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.

Competitive virus assay method for titration of noncytopathogenic bovine viral diarrhea viruses (END⁺ and END⁻ viruses).

Science.gov (United States)

Muhsen, Mahmod; Ohi, Kota; Aoki, Hiroshi; Ikeda, Hidetoshi; Fukusho, Akio

2013-03-01

A new, reliable and secure virus assay method, named the competitive virus assay (CVA) method, has been established for the titration of bovine viral diarrhea viruses (BVDVs) that either show the exaltation of Newcastle disease virus (END) phenomenon or heterologous interference phenomenon (but not the END phenomenon). This method is based on the principle of (1) homologous interference between BVDVs, by using BVDV RK13/E(-) or BVDV RK13/E(+) strains as competitor virus, and (2) END phenomenon and heterologous interference, by using attenuated Newcastle disease virus (NDV) TCND strain as challenge virus. In titration of BVDV END(+) and BVDV END(-) viruses, no significant difference in estimated virus titer was observed between CVA and conventional methods. CVA method demonstrated comparable levels of sensitivity and accuracy as conventional END and interference methods, which require the use of a velogenic Miyadera strain of NDV and vesicular stomatitis virus (VSV), both of which are agents of high-risk diseases. As such, the CVA method is a safer alternative, with increased bio-safety and bio-containment, through avoidance of virulent strains that are commonly employed with conventional methods. Copyright © 2012 Elsevier B.V. All rights reserved.

Virus wars: using one virus to block the spread of another

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Matthew L. Paff

2016-06-01

Full Text Available The failure of traditional interventions to block and cure HIV infections has led to novel proposals that involve treating infections with therapeutic viruses–infectious viruses that specifically inhibit HIV propagation in the host. Early efforts in evaluating these proposals have been limited chiefly to mathematical models of dynamics, for lack of suitable empirical systems. Here we propose, develop and analyze an empirical system of a therapeutic virus that protects a host cell population against a lethal virus. The empirical system uses E. coli bacteria as the host cell population, an RNA phage as the lethal virus and a filamentous phage as the therapeutic virus. Basic dynamic properties are established for each virus alone and then together. Observed dynamics broadly agree with those predicted by a computer simulation model, although some differences are noted. Two cases of dynamics are contrasted, differing in whether the therapeutic virus is introduced before the lethal virus or after the lethal virus. The therapeutic virus increases in both cases but by different mechanisms. With the therapeutic virus introduced first, it spreads infectiously without any appreciable change in host dynamics. With the therapeutic virus introduced second, host abundance is depressed at the time therapy is applied; following an initial period of therapeutic virus spread by infection, the subsequent rise of protection is through reproduction by hosts already protected. This latter outcome is due to inheritance of the therapeutic virus state when the protected cell divides. Overall, the work establishes the feasibility and robustness to details of a viral interference using a therapeutic virus.

Zika virus disease

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Adel I Al-Afaleq

2017-01-01

Full Text Available The Zika virus is an arbovirus belonging to the virus family Flaviviridae. The virus was isolated in 1947 from a rhesus monkey in the Zika Forest of Uganda. The virus causes sporadic mild human infections in Africa and later in Asia. However, by 2007 a major shift in its infection pattern was noticed and thousands of human infections were reported in the State of Yap and Federated States of Micronesia. In the last 3 years, major outbreaks have continued to occur and the virus has spread to several Pacific and American countries. These outbreaks were mostly asymptomatic; however, there were more severe clinical signs associated with the infections. Those signs included microcephaly and Guillain–Barre syndrome. It is believed that various species of mosquitoes can biologically transmit the virus. However, Aedes aegypti is most widely associated with the Zika virus. Recently, new modes of virus transmission have been reported, including mother-to-fetus, sexual, blood transfusion, animal bites, laboratory exposure and breast milk. Differential diagnosis is very important as some other arboviruses such as yellow fever virus, West Nile virus, dengue virus, and chikungunya virus have similar clinical manifestations to the Zika virus infection as well as relating serologically to some of these viruses. Established laboratory diagnostic tests to detect the Zika virus are limited, with reverse transcription polymerase chain reaction being the most widely used test. Taking into consideration the quickness of the spread of infection, size of the infected population and change of the infection severity pattern, the Zika virus infection merits collective efforts on all levels to prevent and control the disease. Limited research work and data, concurrent infection with other arboviruses, involvement of biological vectors, mass crowd events, human and trade movements and lack of vaccines are some of the challenges that we face in our efforts to prevent and

Dengue virus receptor

OpenAIRE

Hidari, Kazuya I.P.J.; Suzuki, Takashi

2011-01-01

Dengue virus is an arthropod-borne virus transmitted by Aedes mosquitoes. Dengue virus causes fever and hemorrhagic disorders in humans and non-human primates. Direct interaction of the virus introduced by a mosquito bite with host receptor molecule(s) is crucial for virus propagation and the pathological progression of dengue diseases. Therefore, elucidation of the molecular mechanisms underlying the interaction between dengue virus and its receptor(s) in both humans and mosquitoes is essent...

ECHO virus

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... page: //medlineplus.gov/ency/article/001340.htm ECHO virus To use the sharing features on this page, please enable JavaScript. Enteric cytopathic human orphan (ECHO) viruses are a group of viruses that can lead ...

Hepatitis E virus coinfection with hepatotropic viruses in Egyptian children.

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Zaki, Maysaa El Sayed; Salama, Osama Saad; Mansour, Fathy Awaad; Hossein, Shaimaa

2008-06-01

Major hepatotropic viruses continue to be important causes of acute viral hepatitis in developing countries. This work was carried out to detect the seroprevalence of hepatitis E virus (HEV) markers in children with acute viral hepatitis due to hepatotropic viruses (A, B and C) and non-A, non-B, non-C acute hepatitis, and to ascertain the influence of HEV superinfection in individuals infected with hepatitis viruses (A, B and C). We studied prospectively 162 children with sporadic acute hepatitis who reported to our hospital. Thirteen healthy controls were also included in the study. Laboratory investigations were performed, including complete liver function tests. Complete serological profiles for hepatitis viruses A, B, C and E were evaluated. HEV immunoglobulin G was detected with highest percentage among patients with hepatitis B (56.7%), followed by patients with hepatitis C virus (52.0%), hepatitis A virus (34.1%) and combined hepatitis B and C viruses (30.0%). The detection rate among patients with non-A, non-B, non-C hepatitis was 7.1%. HEV immunoglobulin M was found in 4.5% of hepatitis A virus patients and in 3.3% of hepatitis B patients. The prevalence of HEV immunoglobulin G and immunoglobulin M correlated with the levels of hepatic aspartate aminotransferase and alanine aminotransferase in patients with dual markers of infection with hepatitis E and other viruses compared to patients with acute hepatitis due to A and C viruses. HEV serological markers are common among children with acute viral hepatitis, especially from hepatitis C and B viruses. There may be increased sensitivity to HEV coinfection in association with hepatitis B and C infections. Dual infection with HEV and other hepatotropic viruses was associated with greater elevation of aspartate and alanine aminotransferases.

Phytophthora viruses.

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Cai, Guohong; Hillman, Bradley I

2013-01-01

Phytophthora sp. is a genus in the oomycetes, which are similar to filamentous fungi in morphology and habitat, but phylogenetically more closely related to brown algae and diatoms and fall in the kingdom Stramenopila. In the past few years, several viruses have been characterized in Phytophthora species, including four viruses from Phytophthora infestans, the late blight pathogen, and an endornavirus from an unnamed Phytophthora species from Douglas fir. Studies on Phytophthora viruses have revealed several interesting systems. Phytophthora infestans RNA virus 1 (PiRV-1) and PiRV-2 are likely the first members of two new virus families; studies on PiRV-3 support the establishment of a new virus genus that is not affiliated with established virus families; PiRV-4 is a member of Narnaviridae, most likely in the genus Narnavirus; and Phytophthora endornavirus 1 (PEV1) was the first nonplant endornavirus at the time of reporting. Viral capsids have not been found in any of the above-mentioned viruses. PiRV-1 demonstrated a unique genome organization that requires further examination, and PiRV-2 may have played a role in late blight resurgence in 1980s-1990s. Copyright © 2013 Elsevier Inc. All rights reserved.

A Serological Survey of Ruminant Livestock in Kazakhstan During Post-Soviet Transitions in Farming and Disease Control

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Corteyn A

2004-12-01

Full Text Available The results of a serological survey of livestock in Kazakhstan, carried out in 1997–1998, are reported. Serum samples from 958 animals (cattle, sheep and goats were tested for antibodies to foot and mouth disease (FMD, bluetongue (BT, epizootic haemorrhagic disease (EHD, rinderpest (RP and peste des petits ruminants (PPR viruses, and to Brucella spp. We also investigated the vaccination status of livestock and related this to changes in veterinary provision since independence in 1991. For the 2 diseases under official surveillance (FMD and brucellosis our results were similar to official data, although we found significantly higher brucellosis levels in 2 districts and widespread ignorance about FMD vaccination status. The seroprevalence for BT virus was 23%, and seropositive animals were widespread suggesting endemicity, despite the disease not having being previously reported. We found a few seropositives for EHDV and PPRV, which may suggest that these diseases are also present in Kazakhstan. An hierarchical model showed that seroprevalence to FMD and BT viruses were clustered at the farm/village level, rather than at a larger spatial scale. This was unexpected for FMD, which is subject to vaccination policies which vary at the raion (county level.

Viruses infecting reptiles.

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Marschang, Rachel E

2011-11-01

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.

Viruses Infecting Reptiles

Directory of Open Access Journals (Sweden)

Rachel E. Marschang

2011-11-01

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.

Characterization of uncultivable bat influenza virus using a replicative synthetic virus.

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Bin Zhou

2014-10-01

Full Text Available Bats harbor many viruses, which are periodically transmitted to humans resulting in outbreaks of disease (e.g., Ebola, SARS-CoV. Recently, influenza virus-like sequences were identified in bats; however, the viruses could not be cultured. This discovery aroused great interest in understanding the evolutionary history and pandemic potential of bat-influenza. Using synthetic genomics, we were unable to rescue the wild type bat virus, but could rescue a modified bat-influenza virus that had the HA and NA coding regions replaced with those of A/PR/8/1934 (H1N1. This modified bat-influenza virus replicated efficiently in vitro and in mice, resulting in severe disease. Additional studies using a bat-influenza virus that had the HA and NA of A/swine/Texas/4199-2/1998 (H3N2 showed that the PR8 HA and NA contributed to the pathogenicity in mice. Unlike other influenza viruses, engineering truncations hypothesized to reduce interferon antagonism into the NS1 protein didn't attenuate bat-influenza. In contrast, substitution of a putative virulence mutation from the bat-influenza PB2 significantly attenuated the virus in mice and introduction of a putative virulence mutation increased its pathogenicity. Mini-genome replication studies and virus reassortment experiments demonstrated that bat-influenza has very limited genetic and protein compatibility with Type A or Type B influenza viruses, yet it readily reassorts with another divergent bat-influenza virus, suggesting that the bat-influenza lineage may represent a new Genus/Species within the Orthomyxoviridae family. Collectively, our data indicate that the bat-influenza viruses recently identified are authentic viruses that pose little, if any, pandemic threat to humans; however, they provide new insights into the evolution and basic biology of influenza viruses.

Characterization of uncultivable bat influenza virus using a replicative synthetic virus.

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Zhou, Bin; Ma, Jingjiao; Liu, Qinfang; Bawa, Bhupinder; Wang, Wei; Shabman, Reed S; Duff, Michael; Lee, Jinhwa; Lang, Yuekun; Cao, Nan; Nagy, Abdou; Lin, Xudong; Stockwell, Timothy B; Richt, Juergen A; Wentworth, David E; Ma, Wenjun

2014-10-01

Bats harbor many viruses, which are periodically transmitted to humans resulting in outbreaks of disease (e.g., Ebola, SARS-CoV). Recently, influenza virus-like sequences were identified in bats; however, the viruses could not be cultured. This discovery aroused great interest in understanding the evolutionary history and pandemic potential of bat-influenza. Using synthetic genomics, we were unable to rescue the wild type bat virus, but could rescue a modified bat-influenza virus that had the HA and NA coding regions replaced with those of A/PR/8/1934 (H1N1). This modified bat-influenza virus replicated efficiently in vitro and in mice, resulting in severe disease. Additional studies using a bat-influenza virus that had the HA and NA of A/swine/Texas/4199-2/1998 (H3N2) showed that the PR8 HA and NA contributed to the pathogenicity in mice. Unlike other influenza viruses, engineering truncations hypothesized to reduce interferon antagonism into the NS1 protein didn't attenuate bat-influenza. In contrast, substitution of a putative virulence mutation from the bat-influenza PB2 significantly attenuated the virus in mice and introduction of a putative virulence mutation increased its pathogenicity. Mini-genome replication studies and virus reassortment experiments demonstrated that bat-influenza has very limited genetic and protein compatibility with Type A or Type B influenza viruses, yet it readily reassorts with another divergent bat-influenza virus, suggesting that the bat-influenza lineage may represent a new Genus/Species within the Orthomyxoviridae family. Collectively, our data indicate that the bat-influenza viruses recently identified are authentic viruses that pose little, if any, pandemic threat to humans; however, they provide new insights into the evolution and basic biology of influenza viruses.

Prevalence of human immunodeficiency virus, hepatitis C virus ...

African Journals Online (AJOL)

Background. Human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV) and syphilis remain major infections around the world. In Angola, about 166 000 individuals are living with HIV, representing a prevalence of 1.98% in adults between 15 and 49 years of age. In a 2003 study in Luanda, 4.5% ...

Epstein - Barr Virus

OpenAIRE

Štorkánová, Lenka

2011-01-01

Epstein-Barr virus Bachelor thesis summarizes the findings of Epstein-Barr virus (EBV), its general characteristics, transmission and spread of the virus, symptoms of disease and subsequent therapy and recovery. More specifically, it focuses on infectious mononucleosis, as well as more generally to other diseases, which the Epstein-Barr virus causes. It includes details of the vaccine against EB virus. There are the statistics on the incidence of infectious mononucleosis.

Emerging influenza viruses and the prospect of a universal influenza virus vaccine.

Science.gov (United States)

Krammer, Florian

2015-05-01

Influenza viruses cause annual seasonal epidemics and pandemics at irregular intervals. Several cases of human infections with avian and swine influenza viruses have been detected recently, warranting enhanced surveillance and the development of more effective countermeasures to address the pandemic potential of these viruses. The most effective countermeasure against influenza virus infection is the use of prophylactic vaccines. However, vaccines that are currently in use for seasonal influenza viruses have to be re-formulated and re-administered in a cumbersome process every year due to the antigenic drift of the virus. Furthermore, current seasonal vaccines are ineffective against novel pandemic strains. This paper reviews zoonotic influenza viruses with pandemic potential and technological advances towards better vaccines that induce broad and long lasting protection from influenza virus infection. Recent efforts have focused on the development of broadly protective/universal influenza virus vaccines that can provide immunity against drifted seasonal influenza virus strains but also against potential pandemic viruses. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Virus-host interaction in feline immunodeficiency virus (FIV) infection.

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Taniwaki, Sueli Akemi; Figueiredo, Andreza Soriano; Araujo, João Pessoa

2013-12-01

Feline immunodeficiency virus (FIV) infection has been the focus of several studies because this virus exhibits genetic and pathogenic characteristics that are similar to those of the human immunodeficiency virus (HIV). FIV causes acquired immunodeficiency syndrome (AIDS) in cats, nevertheless, a large fraction of infected cats remain asymptomatic throughout life despite of persistent chronic infection. This slow disease progression may be due to the presence of factors that are involved in the natural resistance to infection and the immune response that is mounted by the animals, as well as due to the adaptation of the virus to the host. Therefore, the study of virus-host interaction is essential to the understanding of the different patterns of disease course and the virus persistence in the host, and to help with the development of effective vaccines and perhaps the cure of FIV and HIV infections. Copyright © 2013 Elsevier Ltd. All rights reserved.

Systematic analysis of protein identity between Zika virus and other arthropod-borne viruses.

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Chang, Hsiao-Han; Huber, Roland G; Bond, Peter J; Grad, Yonatan H; Camerini, David; Maurer-Stroh, Sebastian; Lipsitch, Marc

2017-07-01

To analyse the proportions of protein identity between Zika virus and dengue, Japanese encephalitis, yellow fever, West Nile and chikungunya viruses as well as polymorphism between different Zika virus strains. We used published protein sequences for the Zika virus and obtained protein sequences for the other viruses from the National Center for Biotechnology Information (NCBI) protein database or the NCBI virus variation resource. We used BLASTP to find regions of identity between viruses. We quantified the identity between the Zika virus and each of the other viruses, as well as within-Zika virus polymorphism for all amino acid k -mers across the proteome, with k ranging from 6 to 100. We assessed accessibility of protein fragments by calculating the solvent accessible surface area for the envelope and nonstructural-1 (NS1) proteins. In total, we identified 294 Zika virus protein fragments with both low proportion of identity with other viruses and low levels of polymorphisms among Zika virus strains. The list includes protein fragments from all Zika virus proteins, except NS3. NS4A has the highest number (190 k -mers) of protein fragments on the list. We provide a candidate list of protein fragments that could be used when developing a sensitive and specific serological test to detect previous Zika virus infections.

Blueberry (Vaccinium corymbosum)-Virus Diseases

Science.gov (United States)

At least six viruses have been found in highbush blueberry plantings in the Pacific Northwest: Blueberry mosaic virus, Blueberry red ringspot virus, Blueberry scorch virus, Blueberry shock virus, Tobacco ringspot virus, and Tomato ringspot virus. Six other virus and virus-like diseases of highbush b...

Single virus genomics: a new tool for virus discovery.

Directory of Open Access Journals (Sweden)

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.

Resistance to Two Heterologous Neurotropic Oncolytic Viruses, Semliki Forest Virus and Vaccinia Virus, in Experimental Glioma

Science.gov (United States)

Le Boeuf, Fabrice; Lemay, Chantal; De Silva, Naomi; Diallo, Jean-Simon; Cox, Julie; Becker, Michelle; Choi, Youngmin; Ananth, Abhirami; Sellers, Clara; Breton, Sophie; Roy, Dominic; Falls, Theresa; Brun, Jan; Hemminki, Akseli; Hinkkanen, Ari; Bell, John C.

2013-01-01

Attenuated Semliki Forest virus (SFV) may be suitable for targeting malignant glioma due to its natural neurotropism, but its replication in brain tumor cells may be restricted by innate antiviral defenses. We attempted to facilitate SFV replication in glioma cells by combining it with vaccinia virus, which is capable of antagonizing such defenses. Surprisingly, we found parenchymal mouse brain tumors to be refractory to both viruses. Also, vaccinia virus appears to be sensitive to SFV-induced antiviral interference. PMID:23221568

Detection of sweet potato virus C, sweet potato virus 2 and sweet potato feathery mottle virus in Portugal.

Science.gov (United States)

Varanda, Carla M R; Santos, Susana J; Oliveira, Mônica D M; Clara, Maria Ivone E; Félix, Maria Rosário F

2015-06-01

Field sweet potato plants showing virus-like symptoms, as stunting, leaf distortion, mosaic and chlorosis, were collected in southwest Portugal and tested for the presence of four potyviruses, sweet potato virus C (SPVC), sweet potato virus 2 (SPV2), sweet potato feathery mottle virus (SPFMV), sweet potato virus G (SPVG), and the crinivirus sweet potato chlorotic stunt virus (SPCSV). DsRNA fractions were extracted from symptomatic leaves and used as templates in single and multiplex RT-PCR assays using previously described specific primers for each analyzed virus. The amplified reaction products for SPVC, SPV2 and SPFMV were of expected size, and direct sequencing of PCR products revealed that they correspond to the coat protein gene (CP) and showed 98%, 99% and 99% identity, respectively, to those viruses. Comparison of the CP genomic and amino acid sequences of the Portuguese viral isolates recovered here with those of ten other sequences of isolates obtained in different countries retrieved from the GenBank showed very few differences. The application of the RT-PCR assays revealed for the first time the presence of SPVC and SPFMV in the sweet potato crop in Portugal, the absence of SPVG and SPCSV in tested plants, as well as the occurrence of triple virus infections under field conditions.

Hepatitis E virus and fulminant hepatitis--a virus or host-specific pathology?

Science.gov (United States)

Smith, Donald B; Simmonds, Peter

2015-04-01

Fulminant hepatitis is a rare outcome of infection with hepatitis E virus. Several recent reports suggest that virus variation is an important determinant of disease progression. To critically examine the evidence that virus-specific factors underlie the development of fulminant hepatitis following hepatitis E virus infection. Published sequence information of hepatitis E virus isolates from patients with and without fulminant hepatitis was collected and analysed using statistical tests to identify associations between virus polymorphisms and disease outcome. Fulminant hepatitis has been reported following infection with all four hepatitis E virus genotypes that infect humans comprising multiple phylogenetic lineages within genotypes 1, 3 and 4. Analysis of virus sequences from individuals infected by a common source did not detect any common substitutions associated with progression to fulminant hepatitis. Re-analysis of previously reported associations between virus substitutions and fulminant hepatitis suggests that these were probably the result of sampling biases. Host-specific factors rather than virus genotype, variants or specific substitutions appear to be responsible for the development of fulminant hepatitis. © 2014 The Authors. Liver International Published by John Wiley & Sons Ltd.

Circulating avian influenza viruses closely related to the 1918 virus have pandemic potential

Science.gov (United States)

Watanabe, Tokiko; Zhong, Gongxun; Russell, Colin A.; Nakajima, Noriko; Hatta, Masato; Hanson, Anthony; McBride, Ryan; Burke, David F.; Takahashi, Kenta; Fukuyama, Satoshi; Tomita, Yuriko; Maher, Eileen A.; Watanabe, Shinji; Imai, Masaki; Neumann, Gabriele; Hasegawa, Hideki; Paulson, James C.; Smith, Derek J.; Kawaoka, Yoshihiro

2014-01-01

Summary Wild birds harbor a large gene pool of influenza A viruses that have the potential to cause influenza pandemics. Foreseeing and understanding this potential is important for effective surveillance. Our phylogenetic and geographic analyses revealed the global prevalence of avian influenza virus genes whose proteins differ only a few amino acids from the 1918 pandemic influenza virus, suggesting that 1918-like pandemic viruses may emerge in the future. To assess this risk, we generated and characterized a virus composed of avian influenza viral segments with high homology to the 1918 virus. This virus exhibited higher pathogenicity in mice and ferrets than an authentic avian influenza virus. Further, acquisition of seven amino acid substitutions in the viral polymerases and the hemagglutinin surface glycoprotein conferred respiratory droplet transmission to the 1918-like avian virus in ferrets, demonstrating that contemporary avian influenza viruses with 1918 virus-like proteins may have pandemic potential. PMID:24922572

Lack of Durable Cross-Neutralizing Antibodies Against Zika Virus from Dengue Virus Infection.

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Collins, Matthew H; McGowan, Eileen; Jadi, Ramesh; Young, Ellen; Lopez, Cesar A; Baric, Ralph S; Lazear, Helen M; de Silva, Aravinda M

2017-05-01

Cross-reactive antibodies elicited by dengue virus (DENV) infection might affect Zika virus infection and confound serologic tests. Recent data demonstrate neutralization of Zika virus by monoclonal antibodies or human serum collected early after DENV infection. Whether this finding is true in late DENV convalescence (>6 months after infection) is unknown. We studied late convalescent serum samples from persons with prior DENV or Zika virus exposure. Despite extensive cross-reactivity in IgG binding, Zika virus neutralization was not observed among primary DENV infections. We observed low-frequency (23%) Zika virus cross-neutralization in repeat DENV infections. DENV-immune persons who had Zika virus as a secondary infection had distinct populations of antibodies that neutralized DENVs and Zika virus, as shown by DENV-reactive antibody depletion experiments. These data suggest that most DENV infections do not induce durable, high-level Zika virus cross-neutralizing antibodies. Zika virus-specific antibody populations develop after Zika virus infection irrespective of prior DENV immunity.

Ganjam virus.

Science.gov (United States)

Sudeep, A B; Jadi, R S; Mishra, A C

2009-11-01

Ganjam virus (GANV), a member of genus Nairovirus of family Bunyavirdae is of considerable veterinary importance in India. Though, predominantly tick borne, GANV was also isolated from mosquitoes, man and sheep. Neutralizing and complement fixing antibodies to GANV have been detected in animal and human sera collected from different parts of the country. Thirty three strains of GANV have been isolated from India, mainly from Haemaphysalis ticks. The virus replicated in certain vertebrate and mosquito cell lines and found pathogenic to laboratory animals. One natural infection and five laboratory-acquired infections in men were also reported. GANV is antigenically related to Nairobi sheep disease virus (NSDV) of Africa, which is highly pathogenic for sheep and goats causing 70-90 per cent mortality among the susceptible population. Recent molecular studies have demonstrated that GANV is an Asian variant of NSDV and both these viruses are related to the dreaded Crimean Congo haemorrhagic fever (CCHF) group viruses. The versatility of the virus to replicate in different arthropod species, its ability to infect sheep, goat and man makes it an important zoonotic agent.

The Drosophila Nora virus is an enteric virus, transmitted via feces.

Science.gov (United States)

Habayeb, Mazen S; Cantera, Rafael; Casanova, Gabriela; Ekström, Jens-Ola; Albright, Shannon; Hultmark, Dan

2009-04-01

The biology of the Drosophila viruses has not been intensely investigated. Here we have investigated the biology of the Nora virus, a persistent Drosophila virus. We find that injected Nora virus is able to replicate in the files, reaching a high titer that is maintained in the next generation. There is a remarkable variation in the viral loads of individual flies in persistently infected stocks; the titers can differ by three orders of magnitude. The Nora virus is mainly found in the intestine of infected flies, and the histology of these infected intestines show increased vacuolization. The virus is excreted in the feces and is horizontally transmitted. The Nora virus infection has a very mild effect on the longevity of the flies, and no significant effect on the number of eggs laid and the percent of eggs that develop to adults.

Herpes viruses and human papilloma virus in nasal polyposis and controls

Directory of Open Access Journals (Sweden)

Dimitrios Ioannidis

2015-12-01

Full Text Available ABSTRACT INTRODUCTION: Chronic rhinosinusitis with nasal polyps is a multifactorial disease entity with an unclear pathogenesis. Contradictory data exist in the literature on the potential implication of viral elements in adult patients with chronic rhinosinusitis. OBJECTIVE: To compare the prevalence of human herpes viruses (1-6 and Human Papilloma Virus in adult patients with chronic rhinosinusitis with nasal polyps and healthy controls. METHODS: Viral DNA presence was evaluated by real-time polymerase chain reaction application to nasal polyps specimens from 91 chronic rhinosinusitis with nasal polyps patients and nasal turbinate mucosa from 38 healthy controls. RESULTS: Epstein-Barr virus positivity was higher in nasal polyps (24/91; 26.4% versus controls (4/38; 10.5%, but the difference did not reach significance (p = 0.06. Human herpes virus-6 positivity was lower in nasal polyps (13/91; 14.29% versus controls (10/38; 26.32%,p = 0.13. In chronic rhinosinusitis with nasal polyps group, 1 sample was herpes simplex virus-1-positive (1/91; 1.1%, and another was cytomegalovirus-positive (1/91; 1.1%, versus none in controls. No sample was positive for herpes simplex virus-2, varicella-zoster virus, high-risk-human papilloma viruses (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59 and low-risk-human papilloma viruses (6, 11. CONCLUSION: Differences in Epstein-Barr virus and human herpes virus-6 positivity among patients with chronic rhinosinusitis with nasal polyps and healthy controls are not statistically significant, weakening the likelihood of their implication in chronic rhinosinusitis with nasal polyps pathogenesis.

Evaluation of recombinant influenza virus-simian immunodeficiency virus vaccines in macaques.

Science.gov (United States)

Sexton, Amy; De Rose, Robert; Reece, Jeanette C; Alcantara, Sheilajen; Loh, Liyen; Moffat, Jessica M; Laurie, Karen; Hurt, Aeron; Doherty, Peter C; Turner, Stephen J; Kent, Stephen J; Stambas, John

2009-08-01

There is an urgent need for human immunodeficiency virus (HIV) vaccines that induce robust mucosal immunity. Influenza A viruses (both H1N1 and H3N2) were engineered to express simian immunodeficiency virus (SIV) CD8 T-cell epitopes and evaluated following administration to the respiratory tracts of 11 pigtail macaques. Influenza virus was readily detected from respiratory tract secretions, although the infections were asymptomatic. Animals seroconverted to influenza virus and generated CD8 and CD4 T-cell responses to influenza virus proteins. SIV-specific CD8 T-cell responses bearing the mucosal homing marker beta7 integrin were induced by vaccination of naïve animals. Further, SIV-specific CD8 T-cell responses could be boosted by recombinant influenza virus-SIV vaccination of animals with already-established SIV infection. Sequential vaccination with influenza virus-SIV recombinants of different subtypes (H1N1 followed by H3N2 or vice versa) produced only a limited boost in immunity, probably reflecting T-cell immunity to conserved internal proteins of influenza A virus. SIV challenge of macaques vaccinated with an influenza virus expressing a single SIV CD8 T cell resulted in a large anamnestic recall CD8 T-cell response, but immune escape rapidly ensued and there was no impact on chronic SIV viremia. Although our results suggest that influenza virus-HIV vaccines hold promise for the induction of mucosal immunity to HIV, broader antigen cover will be needed to limit cytotoxic T-lymphocyte escape.

Schmallenberg virus – et nyt virus hos drøvtyggere

DEFF Research Database (Denmark)

Lohse, Louise

undersøgelser på laboratoriet, blev alle prøver i en længere periode testet negative for kendte patogener, der evt. kunne tænkes at knytte sig til disse sygdomsudbrud. Efterfølgende fandt man ved sekvensanalyse på DNA/RNA oprenset fra prøvematerialet lighed med virus fra orthobunyavirusgruppen. Disse virus er...... normalt vektorbårne og er kendt som årsag til sygdom i drøvtyggere i Australien, Asien, Afrika og Mellemøsten. Det nye virus blev kaldt Schmallenberg virus (SBV) efter stedet hvor det første tilfælde blev påvist. Siden har Schmallenberg virus spredt sig og er nu påvist i får, kvæg og geder i Tyskland......, Holland, Belgien, Luxembourg, Frankrig, Spanien, Italien og Storbritannien (status april 2012). Det antages, at virus overføres med mitter og myg og inkubationstiden har fra eksperimentelle forsøg vist sig at være kort (1-4 dage). Virus cirkulerer få dage i blodet og manifesterer sig ved milde uspecifikke...

Analysis of spatial dynamic of epizootic process of bluetongue and its risk factors.

Science.gov (United States)

Bouchemla, Fayssal; Popova, Olga Mikhailovna; Agoltsov, Valerey Alexandrovich

2017-10-01

The study was undertaken to find out the spatial dynamic occurrence and patterns of the global spread of bluetongue (BT) disease for the period from 1996 to 2016, as well as the assessment of the risk of occurrence and its spread in 2017-2018. Outbreaks (serum samples were collected from clinically healthy as well as suspected animals in infected points) were confirmed and reported officially by veterinary departments which represent different geographical regions in the world to World Organization for Animal Health. These reports explained that ELISA and polymerase chain reaction were used to identify the BT disease, taking in the account number of infected, dead animals, and focus of BT infection in all susceptible animals from 1996 to 2016. Once conventional statistical population was defined (an observational study), we had classified data as well as possible to answer to our aim, using descriptive statistics methods, including the test of the relationship between different epizootiological indicators. The spatial dynamic study of BT's occurrence and its spread in the world over the two past decades was presented by different epizootic indicators. The given analysis includes assessment and measurement of risk factors. It was built too, regression models, and allowed to put different forecasts on the different epizootic indicators in the years 2017-2018 by the extrapolation method. We had also determined that, in 2017, BT continues to spread with the total expectancy of 3.4 focus of infection (number of diseased animals in a single unfavorable point) and mortality of about 26 %; these rates tend to decrease in 2018. At abused points by BT, up to 78.4% of animals are mixed (more than one type) and in 21.6% - uniform. By this way, the relative risk of the incidence of appearance-abused points in mixed households has 3.64, which might be considered higher for the BT dissemination. Moreover, between the enzootic index and other epizootiological indicators had

Analysis of spatial dynamic of epizootic process of bluetongue and its risk factors

Directory of Open Access Journals (Sweden)

Fayssal Bouchemla

2017-10-01

Full Text Available Aim: The study was undertaken to find out the spatial dynamic occurrence and patterns of the global spread of bluetongue (BT disease for the period from 1996 to 2016, as well as the assessment of the risk of occurrence and its spread in 2017-2018. Materials and Methods: Outbreaks (serum samples were collected from clinically healthy as well as suspected animals in infected points were confirmed and reported officially by veterinary departments which represent different geographical regions in the world to World Organization for Animal Health. These reports explained that ELISA and polymerase chain reaction were used to identify the BT disease, taking in the account number of infected, dead animals, and focus of BT infection in all susceptible animals from 1996 to 2016. Once conventional statistical population was defined (an observational study, we had classified data as well as possible to answer to our aim, using descriptive statistics methods, including the test of the relationship between different epizootiological indicators. Results: The spatial dynamic study of BT's occurrence and its spread in the world over the two past decades was presented by different epizootic indicators. The given analysis includes assessment and measurement of risk factors. It was built too, regression models, and allowed to put different forecasts on the different epizootic indicators in the years 2017-2018 by the extrapolation method. We had also determined that, in 2017, BT continues to spread with the total expectancy of 3.4 focus of infection (number of diseased animals in a single unfavorable point and mortality of about 26 %; these rates tend to decrease in 2018. At abused points by BT, up to 78.4% of animals are mixed (more than one type and in 21.6% - uniform. By this way, the relative risk of the incidence of appearance-abused points in mixed households has 3.64, which might be considered higher for the BT dissemination. Moreover, between the enzootic

Sensitive radioimmunosorbent assay for the detection of plant viruses. [Cauliflower mosaic virus, lettuce mosaic virus

Energy Technology Data Exchange (ETDEWEB)

Ghabrial, S A; Shepherd, R J [Kentucky Univ., Lexington (USA); California Univ., Davis (USA))

1980-06-01

A simple and highly sensitive radioimmunosorbent assay (RISA) for the detection of plant viruses is described. The RISA procedure is a microplate method based on the principle of 'double-antibody sandwich' and follows essentially the protocol of the enzyme-linked immunosorbent assay (ELISA) (Clark and Adams, 1977), with the exception that /sup 125/I-labelled ..gamma..-globulin is substituted for the ..gamma..-globulin enzyme conjugate; the bound /sup 125/I-..gamma..-globulin is dissociated by acidification from the double-antibody sandwich. The radioactivity is proportional to virus concentration, and cauliflower mosaic virus (CaMV) and lettuce mosaic virus (LMV) could be detected at concentrations as low as 5 and 2 ng/ml, respectively. Direct evidence of the adverse effects of conjugation with enzyme on the binding abilities of antibodies is presented. The RISA procedure should prove valuable with viruses for which the ELISA values are too low to be dependable.

Release of Virus from Lymphoid Tissue Affects Human Immunodeficiency Virus Type 1 and Hepatitis C Virus Kinetics in the Blood

NARCIS (Netherlands)

Müller, Viktor; Marée, Athanasius F.M.; Boer, R.J. de

2000-01-01

Kinetic parameters of human immunodeficiency virus type 1 (HIV-1) and hepatitis C virus (HCV) infections have been estimated from plasma virus levels following perturbation of the chronically infected (quasi-) steady state. We extend previous models by also considering the large pool of virus

Hepatitis E Virus and Related Viruses in Animals.

Science.gov (United States)

Thiry, D; Mauroy, A; Pavio, N; Purdy, M A; Rose, N; Thiry, E; de Oliveira-Filho, E F

2017-02-01

Hepatitis E is an acute human liver disease in healthy individuals which may eventually become chronic. It is caused by the hepatitis E virus (HEV) and can have a zoonotic origin. Nearly 57,000 people die yearly from hepatitis E-related conditions. The disease is endemic in both developing and developed countries with distinct epidemiologic profiles. In developing countries, the disease is associated with inadequate water treatment, while in developed countries, transmission is associated with animal contact and the ingestion of raw or uncooked meat, especially liver. All human HEV are grouped into at least four genotypes, while HEV or HEV-related viruses have been identified in an increasing number of domestic and wild animal species. Despite a high genetic diversity, only one single HEV serotype has been described to date for HEV genotypes 1-4. The discovery of new HEV or HEV-related viruses leads to a continuing increase in the number of genotypes. In addition, the genome organization of all these viruses is variable with overlapping open reading frames (ORF) and differences in the location of ORF3. In spite of the role of some domestic and wild animals as reservoir, the origin of HEV and HEV-related viruses in humans and animals is still unclear. This review discusses aspects of the detection, molecular virology, zoonotic transmission and origin of HEV and HEV-related viruses in the context of 'One Health' and establishes a link between the previous and the new taxonomy of this growing virus family. © 2015 Blackwell Verlag GmbH.

"The evil virus cell": Students' knowledge and beliefs about viruses.

Science.gov (United States)

Simon, Uwe K; Enzinger, Sonja M; Fink, Andreas

2017-01-01

Education about virus biology at school is of pivotal interest to raise public awareness concerning means of disease transmission and, thus, methods to prevent infection, and to reduce unnecessary antibiotic treatment due to patient pressure on physicians in case of viral diseases such as influenza. This study aimed at making visible the knowledge of Austrian high school and university students with respect to virus biology, virus structure and health-education issues. The data presented here stem from comprehensive questionnaire analyses, including the task to draw a virus, from a cross-sectional study with 133 grade 7 and 199 grade 10 high school students, and 133 first-year biology and 181 first-year non-biology university students. Analyses were performed both quantitatively and qualitatively. ANOVA revealed a highly significant group effect for total knowledge relating to virus biology and health issues (F(3, 642) = 44.17, p students and grade 10 high school students. Students enrolled in university-level biology outperformed all other groups, even though they had not yet encountered this topic at their courses; part of this phenomenon might be due to their affinity for learning about biological topics. However, even many first-year biology students had a high number of severe misconceptions, e.g., defining a virus as a pro- or eukaryotic cell, or falsely naming malaria as a viral disease. Since there was no significant difference in virus-related knowledge between high schools, virus biology seems to have been taught similarly among the tested schools. However, the majority of participants stated that the virus-related knowledge they had acquired at school was not sufficient. Based on the results presented here we urgently suggest improving and intensifying teaching this topic at school, since virus-related knowledge was by far too fragmentary among many participants. Such lack of health-relevant knowledge may contribute to pressure on physicians by patients

Herpes viruses and human papilloma virus in nasal polyposis and controls.

Science.gov (United States)

Ioannidis, Dimitrios; Lachanas, Vasileios A; Florou, Zoe; Bizakis, John G; Petinaki, Efthymia; Skoulakis, Charalampos E

2015-01-01

Chronic rhinosinusitis with nasal polyps is a multifactorial disease entity with an unclear pathogenesis. Contradictory data exist in the literature on the potential implication of viral elements in adult patients with chronic rhinosinusitis. To compare the prevalence of human herpes viruses (1-6) and Human Papilloma Virus in adult patients with chronic rhinosinusitis with nasal polyps and healthy controls. Viral DNA presence was evaluated by real-time polymerase chain reaction application to nasal polyps specimens from 91 chronic rhinosinusitis with nasal polyps patients and nasal turbinate mucosa from 38 healthy controls. Epstein-Barr virus positivity was higher in nasal polyps (24/91; 26.4%) versus controls (4/38; 10.5%), but the difference did not reach significance (p=0.06). Human herpes virus-6 positivity was lower in nasal polyps (13/91; 14.29%) versus controls (10/38; 26.32%, p=0.13). In chronic rhinosinusitis with nasal polyps group, 1 sample was herpes simplex virus-1-positive (1/91; 1.1%), and another was cytomegalovirus-positive (1/91; 1.1%), versus none in controls. No sample was positive for herpes simplex virus-2, varicella-zoster virus, high-risk-human papilloma viruses (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59) and low-risk-human papilloma viruses (6, 11). Differences in Epstein-Barr virus and human herpes virus-6 positivity among patients with chronic rhinosinusitis with nasal polyps and healthy controls are not statistically significant, weakening the likelihood of their implication in chronic rhinosinusitis with nasal polyps pathogenesis. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Computer Virus and Trends

OpenAIRE

Tutut Handayani; Soenarto Usna,Drs.MMSI

2004-01-01

Since its appearance the first time in the mid-1980s, computer virus has invited various controversies that still lasts to this day. Along with the development of computer systems technology, viruses komputerpun find new ways to spread itself through a variety of existing communications media. This paper discusses about some things related to computer viruses, namely: the definition and history of computer viruses; the basics of computer viruses; state of computer viruses at this time; and ...

Viruses in reptiles

Directory of Open Access Journals (Sweden)

Ariel Ellen

2011-09-01

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

Genomic characterisation of Almpiwar virus, Harrison Dam virus and Walkabout Creek virus; three novel rhabdoviruses from northern Australia

Directory of Open Access Journals (Sweden)

Jane McAllister

2014-09-01

Full Text Available Rhabdoviridae represent a diverse group of viruses with the potential to cause disease in humans, animals and plants. Currently there are nine genera in the family; however a large number of rhabdoviruses remain unassigned. Here we characterise three novel rhabdoviruses genomes. Almpiwar virus (ALMV, isolated from skinks in northern Queensland, is the first completely sequenced rhabdovirus from squamates, with serological studies indicating multiple animal host species. Harrison Dam virus (HARDV and Walkabout Creek virus (WACV were isolated from mosquitoes in the Northern Territory and biting midges in southern Queensland respectively and their vertebrate hosts remain unknown. Serological cross-neutralisation tests with other Australian rhabdoviruses indicate that ALMV, WACV and HARDV are distinct viruses with little antigenic cross-reactivity. Next-generation sequencing revealed that all viruses encode the core proteins common to rhabdoviruses (N, P, M, G and L, plus additional ORFs between the M and G genes. HARDV also contains a small ORF between the G and L genes. Phylogenetic analysis of N and L proteins suggests that HARDV and WACV share a common lineage with the tupaviruses and Sandjimba group, whereas ALMV is a distinct and divergent virus showing no clear relationship to any rhabdovirus except the recently characterised Niahka virus (NIAV.

Powassan (POW) Virus Basics

Science.gov (United States)

... Health Professionals Related Topics For International Travelers Powassan Virus Disease Basics Download this fact sheet formatted for ... Virus Disease Fact Sheet (PDF) What is Powassan virus? Powassan virus is a tickborne flavivirus that is ...

Initial characterization of Vaccinia Virus B4 suggests a role in virus spread

Energy Technology Data Exchange (ETDEWEB)

Burles, Kristin; Irwin, Chad R.; Burton, Robyn-Lee [Li Ka Shing Institute of Virology, Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada T6G 2S2 (Canada); Schriewer, Jill [Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, St. Louis, MO (United States); Evans, David H. [Li Ka Shing Institute of Virology, Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada T6G 2S2 (Canada); Buller, R. Mark [Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, St. Louis, MO (United States); Barry, Michele, E-mail: michele.barry@ualberta.ca [Li Ka Shing Institute of Virology, Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada T6G 2S2 (Canada)

2014-05-15

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.

Initial characterization of Vaccinia Virus B4 suggests a role in virus spread

International Nuclear Information System (INIS)

Burles, Kristin; Irwin, Chad R.; Burton, Robyn-Lee; Schriewer, Jill; Evans, David H.; Buller, R. Mark; Barry, Michele

2014-01-01

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

How Hepatitis D Virus Can Hinder the Control of Hepatitis B Virus

NARCIS (Netherlands)

Xiridiou, M.; Borkent-Raven, B.; Hulshof, J.; Wallinga, J.

2009-01-01

Background: Hepatitis D (or hepatitis delta) virus is a defective virus that relies on hepatitis B virus (HBV) for transmission; infection with hepatitis D can occur only as coinfection with HBV or superinfection of an existing HBV infection. Because of the bond between the two viruses, control

9 CFR 113.215 - Bovine Virus Diarrhea Vaccine, Killed Virus.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Bovine Virus Diarrhea Vaccine, Killed Virus. 113.215 Section 113.215 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD...

Influenza (Flu) Viruses

Science.gov (United States)

... Types Seasonal Avian Swine Variant Pandemic Other Influenza (Flu) Viruses Language: English (US) Español Recommend on Facebook ... influenza circulate and cause illness. More Information about Flu Viruses Types of Influenza Viruses Influenza A and ...

[The growth of attenuated strains of canine parvovirus, mink enteritis virus, feline panleukopenia virus, and rabies virus on various types of cell cultures].

Science.gov (United States)

Zuffa, T

1987-10-01

The growth characteristics were studied in the attenuated strains of canine parvovirus CPVA-BN 80/82, mink enteritis virus MEVA-BN 63/82 and feline panleucopenia virus FPVA-BN 110/83 on the stable feline kidney cell line FE, and in the attenuated canine distemper virus CDV-F-BN 10/83 on chicken embryo cell cultures (KEB) and cultures of the stable cell line VERO. When the FE cultures were infected with different parvoviruses in cell suspension at MOI 2-4 TKID50 per cell, the first multiplication of the intracellular virus was recorded 20 hours p. i. In the canine parvovirus, the content of intracellular and extracellular virus continued increasing parallelly until the fourth day; then, from the fourth to the sixth day, the content of extracellular virus still increased whereas that of intracellular virus fell rapidly. In the case of the mink enteritis virus the release of the virus into the culture medium continued parallelly with the production of the cellular virus until the sixth day. In the case of the feline panleucopenia virus the values concerning free virus and virus bound to cells were lower, starting from the second day p. i. When KEB or VERO cultures were infected in cell suspension with the canine distemper virus at MOI about 0.004 per 1 cell, the replicated intracellular virus was first recorded in the KEB cultures five hours after infection but in the VERO cultures only 20 hours after infection, with a timely release of the virus into the culture medium in both kinds of tissue. In the KEB and VERO cultures the highest values of infection titres were recorded on the fourth day p. i., the course of virus multiplication on the cells being parallel with its release into the culture medium.

Understanding Spatio-Temporal Variability in the Reproduction Ratio of the Bluetongue (BTV-1 Epidemic in Southern Spain (Andalusia in 2007 Using Epidemic Trees.

Directory of Open Access Journals (Sweden)

S Napp

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

Viruses of asparagus.

Science.gov (United States)

Tomassoli, Laura; Tiberini, Antonio; Vetten, Heinrich-Josef

2012-01-01

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. Copyright © 2012 Elsevier Inc. All rights reserved.

Viruses and Breast Cancer

Science.gov (United States)

Lawson, James S.; Heng, Benjamin

2010-01-01

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. PMID:24281093

Viruses and Breast Cancer

International Nuclear Information System (INIS)

Lawson, James S.; Heng, Benjamin

2010-01-01

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

Viruses and Breast Cancer

Energy Technology Data Exchange (ETDEWEB)

Lawson, James S., E-mail: james.lawson@unsw.edu.au; Heng, Benjamin [School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney (Australia)

2010-04-30

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.

"The evil virus cell": Students‘ knowledge and beliefs about viruses

Science.gov (United States)

Enzinger, Sonja M.; Fink, Andreas

2017-01-01

Education about virus biology at school is of pivotal interest to raise public awareness concerning means of disease transmission and, thus, methods to prevent infection, and to reduce unnecessary antibiotic treatment due to patient pressure on physicians in case of viral diseases such as influenza. This study aimed at making visible the knowledge of Austrian high school and university students with respect to virus biology, virus structure and health-education issues. The data presented here stem from comprehensive questionnaire analyses, including the task to draw a virus, from a cross-sectional study with 133 grade 7 and 199 grade 10 high school students, and 133 first-year biology and 181 first-year non-biology university students. Analyses were performed both quantitatively and qualitatively. ANOVA revealed a highly significant group effect for total knowledge relating to virus biology and health issues (F(3, 642) = 44.17, p students and grade 10 high school students. Students enrolled in university-level biology outperformed all other groups, even though they had not yet encountered this topic at their courses; part of this phenomenon might be due to their affinity for learning about biological topics. However, even many first-year biology students had a high number of severe misconceptions, e.g., defining a virus as a pro- or eukaryotic cell, or falsely naming malaria as a viral disease. Since there was no significant difference in virus-related knowledge between high schools, virus biology seems to have been taught similarly among the tested schools. However, the majority of participants stated that the virus-related knowledge they had acquired at school was not sufficient. Based on the results presented here we urgently suggest improving and intensifying teaching this topic at school, since virus-related knowledge was by far too fragmentary among many participants. Such lack of health-relevant knowledge may contribute to pressure on physicians by patients

Influenza virus inactivated by artificial ribonucleases as a prospective killed virus vaccine.

Science.gov (United States)

Fedorova, Antonina A; Goncharova, Elena P; Kovpak, Mikhail P; Vlassov, Valentin V; Zenkova, Marina A

2012-04-19

The inactivation of viral particles with agents causing minimal damage to the structure of surface epitopes is a well-established approach for the production of killed virus vaccines. Here, we describe new agents for the inactivation of influenza virus, artificial ribonucleases (aRNases), which are chemical compounds capable of cleaving RNA molecules. Several aRNases were identified, exhibiting significant virucidal activity against the influenza A virus and causing a minimal effect on the affinity of monoclonal antibodies for the inactivated virus. Using a murine model of the influenza virus infection, a high protective activity of the aRNase-inactivated virus as a vaccine was demonstrated. The results of the experiments demonstrate the efficacy of novel chemical agents in the preparation of vaccines against influenza and, perhaps, against other infections caused by RNA viruses. Copyright © 2012 Elsevier Ltd. All rights reserved.

RNA interference targets arbovirus replication in Culicoides cells.

Science.gov (United States)

Schnettler, Esther; Ratinier, Maxime; Watson, Mick; Shaw, Andrew E; McFarlane, Melanie; Varela, Mariana; Elliott, Richard M; Palmarini, Massimo; Kohl, Alain

2013-03-01

Arboviruses are transmitted to vertebrate hosts by biting arthropod vectors such as mosquitoes, ticks, and midges. These viruses replicate in both arthropods and vertebrates and are thus exposed to different antiviral responses in these organisms. RNA interference (RNAi) is a sequence-specific RNA degradation mechanism that has been shown to play a major role in the antiviral response against arboviruses in mosquitoes. Culicoides midges are important vectors of arboviruses, known to transmit pathogens of humans and livestock such as bluetongue virus (BTV) (Reoviridae), Oropouche virus (Bunyaviridae), and likely the recently discovered Schmallenberg virus (Bunyaviridae). In this study, we investigated whether Culicoides cells possess an antiviral RNAi response and whether this is effective against arboviruses, including those with double-stranded RNA (dsRNA) genomes, such as BTV. Using reporter gene-based assays, we established the presence of a functional RNAi response in Culicoides sonorensis-derived KC cells which is effective in inhibiting BTV infection. Sequencing of small RNAs from KC and Aedes aegypti-derived Aag2 cells infected with BTV or the unrelated Schmallenberg virus resulted in the production of virus-derived small interfering RNAs (viRNAs) of 21 nucleotides, similar to the viRNAs produced during arbovirus infections of mosquitoes. In addition, viRNA profiles strongly suggest that the BTV dsRNA genome is accessible to a Dicer-type nuclease. Thus, we show for the first time that midge cells target arbovirus replication by mounting an antiviral RNAi response mainly resembling that of other insect vectors of arboviruses.

Health assessment of wild lowland tapir (Tapirus terrestris) populations in the Atlantic Forest and Pantanal biomes, Brazil (1996-2012).

Science.gov (United States)

Medici, Emília Patrícia; Mangini, Paulo Rogerio; Fernandes-Santos, Renata Carolina

2014-10-01

Abstract The lowland tapir (Tapirus terrestris) is found in South America and is listed as Vulnerable to Extinction by the International Union for Conservation of Nature, Red List of Threatened Species. Health issues, particularly infectious diseases, are potential threats for the species. Health information from 65 wild tapirs from two Brazilian biomes, Atlantic Forest (AF) and Pantanal (PA), were collected during a long-term study (1996-2012). The study included physic, hematologic and biochemical evaluations, microbiologic cultures, urinalysis, and serologic analyses for antibodies against 13 infectious agents (viral and bacterial). The AF and PA tapirs were significantly different for several hematologic and biochemical parameters. Ten bacteria taxa were identified in the AF and 26 in the PA. Antibodies against five viruses were detected: Bluetongue virus, eastern equine encephalitis virus, western equine encephalitis virus, infectious bovine rhinotracheitis virus, and porcine parvovirus. A high prevalence of exposure to Leptospira interrogans (10 serovars: Autumnalis, Bratislava, Canicola, Copenhageni, Grippotyphosa, Hardjo, Hebdomadis, Icterohaemorrhagiae, Pomona, and Pyrogenes) was detected in both the AF and PA sites. A greater diversity of serovars and higher antibody titers were found in the PA. Statistically significant differences between sites were found for L. interrogans, equine encephalitis virus, and porcine parvovirus. Based on physical evaluations, both AF and PA populations were healthy. The differences in the overall health profile of the AF and PA tapir populations appear to be associated with environmental factors and infectious diseases ecology. The extensive datasets on hematology, biochemistry, urinalysis, and microbiology results from this paper can be used as reference values for wild tapirs.

[The great virus comeback].

Science.gov (United States)

Forterre, Patrick

2013-01-01

Viruses have been considered for a long time as by-products of biological evolution. This view is changing now as a result of several recent discoveries. Viral ecologists have shown that viral particles are the most abundant biological entities on our planet, whereas metagenomic analyses have revealed an unexpected abundance and diversity of viral genes in the biosphere. Comparative genomics have highlighted the uniqueness of viral sequences, in contradiction with the traditional view of viruses as pickpockets of cellular genes. On the contrary, cellular genomes, especially eukaryotic ones, turned out to be full of genes derived from viruses or related elements (plasmids, transposons, retroelements and so on). The discovery of unusual viruses infecting archaea has shown that the viral world is much more diverse than previously thought, ruining the traditional dichotomy between bacteriophages and viruses. Finally, the discovery of giant viruses has blurred the traditional image of viruses as small entities. Furthermore, essential clues on virus history have been obtained in the last ten years. In particular, structural analyses of capsid proteins have uncovered deeply rooted homologies between viruses infecting different cellular domains, suggesting that viruses originated before the last universal common ancestor (LUCA). These studies have shown that several lineages of viruses originated independently, i.e., viruses are polyphyletic. From the time of LUCA, viruses have coevolved with their hosts, and viral lineages can be viewed as lianas wrapping around the trunk, branches and leaves of the tree of life. Although viruses are very diverse, with genomes encoding from one to more than one thousand proteins, they can all be simply defined as organisms producing virions. Virions themselves can be defined as infectious particles made of at least one protein associated with the viral nucleic acid, endowed with the capability to protect the viral genome and ensure its

Protoplasts and plant viruses

International Nuclear Information System (INIS)

Murakishi, H.; Lesney, M.S.; Carlson, P.

1984-01-01

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

Hepatitis A Virus and Hepatitis E Virus: Emerging and Re-Emerging Enterically Transmitted Hepatitis Viruses.

Science.gov (United States)

Lemon, Stanley M; Walker, Christopher M

2018-05-07

Over the past two decades, progress in understanding human infections with hepatitis A virus (HAV) and hepatitis E virus (HEV) has been eclipsed by the priority of combating persistent hepatitis B virus (HBV) and hepatitis C virus (HCV) infections. During that time, the global burden of liver disease caused by enteric hepatitis viruses has not abated. Because of vaccines, hepatitis A has become increasingly a disease of adults instead of early childhood in many regions of the world, resulting in an age-related shift toward more severe disease. HEV has remained endemic in many developing countries, and in well-developed, economically advanced countries it is now recognized as a cause of chronic, progressive liver disease in individuals with compromised immunity. The goal of this collection of articles is to review recent progress and to shine a bright light on gaps in our understanding of how these viruses replicate, cause disease, interact with the liver and host immune system, and are transmitted, along with prospects for improved control in human populations. Renewed efforts to study and compare HAV and HEV biology in humans and animal models have high potential to enhance our understanding of host-pathogen balance in the liver, and may contribute ultimately to the control of other infectious diseases of the liver. Copyright © 2018 Cold Spring Harbor Laboratory Press; all rights reserved.

Evolutionary ecology of virus emergence.

Science.gov (United States)

Dennehy, John J

2017-02-01

The cross-species transmission of viruses into new host populations, termed virus emergence, is a significant issue in public health, agriculture, wildlife management, and related fields. Virus emergence requires overlap between host populations, alterations in virus genetics to permit infection of new hosts, and adaptation to novel hosts such that between-host transmission is sustainable, all of which are the purview of the fields of ecology and evolution. A firm understanding of the ecology of viruses and how they evolve is required for understanding how and why viruses emerge. In this paper, I address the evolutionary mechanisms of virus emergence and how they relate to virus ecology. I argue that, while virus acquisition of the ability to infect new hosts is not difficult, limited evolutionary trajectories to sustained virus between-host transmission and the combined effects of mutational meltdown, bottlenecking, demographic stochasticity, density dependence, and genetic erosion in ecological sinks limit most emergence events to dead-end spillover infections. Despite the relative rarity of pandemic emerging viruses, the potential of viruses to search evolutionary space and find means to spread epidemically and the consequences of pandemic viruses that do emerge necessitate sustained attention to virus research, surveillance, prophylaxis, and treatment. © 2016 New York Academy of Sciences.

A virus of hyperthermophilic archaea with a unique architecture among DNA viruses.

Science.gov (United States)

Rensen, Elena Ilka; Mochizuki, Tomohiro; Quemin, Emmanuelle; Schouten, Stefan; Krupovic, Mart; Prangishvili, David

2016-03-01

Viruses package their genetic material in diverse ways. Most known strategies include encapsulation of nucleic acids into spherical or filamentous virions with icosahedral or helical symmetry, respectively. Filamentous viruses with dsDNA genomes are currently associated exclusively with Archaea. Here, we describe a filamentous hyperthermophilic archaeal virus, Pyrobaculum filamentous virus 1 (PFV1), with a type of virion organization not previously observed in DNA viruses. The PFV1 virion, 400 ± 20 × 32 ± 3 nm, contains an envelope and an inner core consisting of two structural units: a rod-shaped helical nucleocapsid formed of two 14-kDa major virion proteins and a nucleocapsid-encompassing protein sheath composed of a single major virion protein of 18 kDa. The virion organization of PFV1 is superficially similar to that of negative-sense RNA viruses of the family Filoviridae, including Ebola virus and Marburg virus. The linear dsDNA of PFV1 carries 17,714 bp, including 60-bp-long terminal inverted repeats, and contains 39 predicted ORFs, most of which do not show similarities to sequences in public databases. PFV1 is a lytic virus that completely disrupts the host cell membrane at the end of the infection cycle.

DIAGNOSTICS OF VIRUS PHYTOPATHOGENS FRUIT TREE PLUM POX VIRUS, PRUNUS NECROTIC RINGSPOT VIRUS AND PRUNUS DWARF VIRUS BY BIOLOGICAL AND MOLECULAR DIAGNOSTICS

OpenAIRE

Július Rozák; Zdenka Gálová

2013-01-01

The aim of this study was to determine the incidence of viral phytopathogen Plum pox virus, Prunus necrotic ringspot virus and Prunus dwarf virus in selected localities of Slovakia and diagnose them using a molecular and biological methods. Forty samples of fruit trees of the genus Prunus, twenty samples from intensive plantings and twenty samples from wild subject were analysed. Biological diagnostic by using biological indicators Prunus persica cv. GF 305, Prunus serrulata cv. Schirofugen a...

Functional properties of Virus-Encoded and Virus-Regulated 7TM Receptors

DEFF Research Database (Denmark)

Spiess, Katja; Rosenkilde, Mette Marie

2014-01-01

During co-evolution with their hosts, viruses have developed several survival strategies that involve exploitation of 7TM receptors. These include virus-encoded 7TM receptors and ligands and viral regulation of endogenous receptors. Many functional properties have been ascribed to virus-exploited...

Electron microscopic identification of Zinga virus as a strain of Rift Valley fever virus.

Science.gov (United States)

Olaleye, O D; Baigent, C L; Mueller, G; Tomori, O; Schmitz, H

1992-01-01

Electron microscopic examination of a negatively stained suspension of Zinga virus showed particles 90-100 nm in diameter, enveloped with spikes 12-20 nm in length and 5 nm in diameter. Further identification of the virus by immune electron microscopy showed the reactivity of human Rift Valley fever virus-positive serum with Zinga virus. Results of this study are in agreement with earlier reports that Zinga virus is a strain of Rift Valley fever virus.

Nonhuman Primate Models of Hepatitis A Virus and Hepatitis E Virus Infections.

Science.gov (United States)

Lanford, Robert E; Walker, Christopher M; Lemon, Stanley M

2018-04-23

Although phylogenetically unrelated, human hepatitis viruses share an exclusive or near exclusive tropism for replication in differentiated hepatocytes. This narrow tissue tropism may contribute to the restriction of the host ranges of these viruses to relatively few host species, mostly nonhuman primates. Nonhuman primate models thus figure prominently in our current understanding of the replication and pathogenesis of these viruses, including the enterically transmitted hepatitis A virus (HAV) and hepatitis E virus (HEV), and have also played major roles in vaccine development. This review draws comparisons of HAV and HEV infection from studies conducted in nonhuman primates, and describes how such studies have contributed to our current understanding of the biology of these viruses. Copyright © 2018 Cold Spring Harbor Laboratory Press; all rights reserved.

Zika Virus

Science.gov (United States)

... Funding CDC Activities For Healthcare Providers Clinical Evaluation & Disease Sexual Transmission HIV Infection & Zika Virus Testing for Zika Test Specimens – At Time of Birth Diagnostic Tests Understanding Zika Virus Test Results ...

Hepatitis C virus infection in the human immunodeficiency virus infected patient

DEFF Research Database (Denmark)

Clausen, Louise Nygaard; Lundbo, Lene Fogt; Benfield, Thomas

2014-01-01

Human immunodeficiency virus (HIV) and hepatitis C virus (HCV) share the same transmission routes; therefore, coinfection is frequent. An estimated 5-10 million individuals alone in the western world are infected with both viruses. The majority of people acquire HCV by injection drug use and...

Immunological responses against human papilloma virus and human papilloma virus induced laryngeal cancer.

Science.gov (United States)

Chitose, Shun-ichi; Sakazaki, T; Ono, T; Kurita, T; Mihashi, H; Nakashima, T

2010-06-01

This study aimed to clarify the local immune status in the larynx in the presence of infection or carcinogenesis associated with human papilloma virus. Cytological samples (for human papilloma virus detection) and laryngeal secretions (for immunoglobulin assessment) were obtained from 31 patients with laryngeal disease, during microscopic laryngeal surgery. On histological examination, 12 patients had squamous cell carcinoma, four had laryngeal papilloma and 15 had other benign laryngeal disease. Cytological samples were tested for human papilloma virus DNA using the Hybrid Capture 2 assay. High risk human papilloma virus DNA was detected in 25 per cent of patients (three of 12) with laryngeal cancer. Low risk human papilloma virus DNA was detected only in three laryngeal papilloma patients. The mean laryngeal secretion concentrations of immunoglobulins M, G and A and secretory immunoglobulin A in human papilloma virus DNA positive patients were more than twice those in human papilloma virus DNA negative patients. A statistically significant difference was observed between the secretory immunoglobulin A concentrations in the two groups. Patients with laryngeal cancer had higher laryngeal secretion concentrations of each immunoglobulin type, compared with patients with benign laryngeal disease. The study assessed the mean laryngeal secretion concentrations of each immunoglobulin type in the 12 laryngeal cancer patients, comparing human papilloma virus DNA positive patients (n = 3) and human papilloma virus DNA negative patients (n = 9); the mean concentrations of immunoglobulins M, G and A and secretory immunoglobulin A tended to be greater in human papilloma virus DNA positive cancer patients, compared with human papilloma virus DNA negative cancer patients. These results suggest that the local laryngeal immune response is activated by infection or carcinogenesis due to human papilloma virus. The findings strongly suggest that secretory IgA has inhibitory activity

Deep-Sea Hydrothermal Vent Viruses Compensate for Microbial Metabolism in Virus-Host Interactions.

Science.gov (United States)

He, Tianliang; Li, Hongyun; Zhang, Xiaobo

2017-07-11

Viruses are believed to be responsible for the mortality of host organisms. However, some recent investigations reveal that viruses may be essential for host survival. To date, it remains unclear whether viruses are beneficial or harmful to their hosts. To reveal the roles of viruses in the virus-host interactions, viromes and microbiomes of sediment samples from three deep-sea hydrothermal vents were explored in this study. To exclude the influence of exogenous DNAs on viromes, the virus particles were purified with nuclease (DNase I and RNase A) treatments and cesium chloride density gradient centrifugation. The metagenomic analysis of viromes without exogenous DNA contamination and microbiomes of vent samples indicated that viruses had compensation effects on the metabolisms of their host microorganisms. Viral genes not only participated in most of the microbial metabolic pathways but also formed branched pathways in microbial metabolisms, including pyrimidine metabolism; alanine, aspartate, and glutamate metabolism; nitrogen metabolism and assimilation pathways of the two-component system; selenocompound metabolism; aminoacyl-tRNA biosynthesis; and amino sugar and nucleotide sugar metabolism. As is well known, deep-sea hydrothermal vent ecosystems exist in relatively isolated environments which are barely influenced by other ecosystems. The metabolic compensation of hosts mediated by viruses might represent a very important aspect of virus-host interactions. IMPORTANCE Viruses are the most abundant biological entities in the oceans and have very important roles in regulating microbial community structure and biogeochemical cycles. The relationship between virus and host microbes is broadly thought to be that of predator and prey. Viruses can lyse host cells to control microbial population sizes and affect community structures of hosts by killing specific microbes. However, viruses also influence their hosts through manipulation of bacterial metabolism. We found

Viruses in reptiles.

Science.gov (United States)

Ariel, Ellen

2011-09-21

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.

A REVIEW ON ZIKA VIRUS (ZIKV) -A DREADFUL MEMBER OF THE VIRUS FAMILY FLAVIVIRIDAE

OpenAIRE

1Rafiya Begum, 2 Raafia Aseena, 3Nuha Rasheed and 4 Abdul Saleem Mohammad

2017-01-01

Research on zika virus examine the virus that is spread to humans through a mosquito bite, with symptoms that include fever, rash, joint pain, and conjuctivities. For most people zika virus is not necessarily anything to worry, as it is not fatal and symptoms are generally mild for period up to a week. Hospitalization because of zika virus is almost always not necessary. However, the zika virus can be extremely dangerous to pregnant womes. Key Words: Zika, virus, transmission, fatal, flavivir...

Type C virus activation in nontransformed mouse cells by uv-irradiated herpes simplex virus

Energy Technology Data Exchange (ETDEWEB)

Hampar, B. (National Institutes of Health, Bethesda, MD); Hatanaka, M.; Aulakh, G.; Derge, J.G.; Lee, L.; Showalter, S.

1977-02-01

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.

Type C virus activation in nontransformed mouse cells by uv-irradiated herpes simplex virus

International Nuclear Information System (INIS)

Hampar, B.; Hatanaka, M.; Aulakh, G.; Derge, J.G.; Lee, L.; Showalter, S.

1977-01-01

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

Chikungunya virus

Science.gov (United States)

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 ...

Perinatal hepatitis B virus detection by hepatitis B virus-DNA analysis.

OpenAIRE

De Virgiliis, S; Frau, F; Sanna, G; Turco, M P; Figus, A L; Cornacchia, G; Cao, A

1985-01-01

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.

Virus like particle-based vaccines against emerging infectious disease viruses.

Science.gov (United States)

Liu, Jinliang; Dai, Shiyu; Wang, Manli; Hu, Zhihong; Wang, Hualin; Deng, Fei

2016-08-01

Emerging infectious diseases are major threats to human health. Most severe viral disease outbreaks occur in developing regions where health conditions are poor. With increased international travel and business, the possibility of eventually transmitting infectious viruses between different countries is increasing. The most effective approach in preventing viral diseases is vaccination. However, vaccines are not currently available for numerous viral diseases. Virus-like particles (VLPs) are engineered vaccine candidates that have been studied for decades. VLPs are constructed by viral protein expression in various expression systems that promote the selfassembly of proteins into structures resembling virus particles. VLPs have antigenicity similar to that of the native virus, but are non-infectious as they lack key viral genetic material. VLP vaccines have attracted considerable research interest because they offer several advantages over traditional vaccines. Studies have shown that VLP vaccines can stimulate both humoral and cellular immune responses, which may offer effective antiviral protection. Here we review recent developments with VLP-based vaccines for several highly virulent emerging or re-emerging infectious diseases. The infectious agents discussed include RNA viruses from different virus families, such as the Arenaviridae, Bunyaviridae, Caliciviridae, Coronaviridae, Filoviridae, Flaviviridae, Orthomyxoviridae, Paramyxoviridae, and Togaviridae families.

Immunogenicity of a modified-live virus vaccine against bovine viral diarrhea virus types 1 and 2, infectious bovine rhinotracheitis virus, bovine parainfluenza-3 virus, and bovine respiratory syncytial virus when administered intranasally in young calves.

Science.gov (United States)

Xue, Wenzhi; Ellis, John; Mattick, Debra; Smith, Linda; Brady, Ryan; Trigo, Emilio

2010-05-14

The immunogenicity of an intranasally-administered modified-live virus (MLV) vaccine in 3-8 day old calves was evaluated against bovine viral diarrhea virus (BVDV) types 1 and 2, infectious bovine rhinotracheitis (IBR) virus, parainfluenza-3 (PI-3) virus and bovine respiratory syncytial virus (BRSV). Calves were intranasally vaccinated with a single dose of a multivalent MLV vaccine and were challenged with one of the respective viruses three to four weeks post-vaccination in five separate studies. There was significant sparing of diseases in calves intranasally vaccinated with the MLV vaccine, as indicated by significantly fewer clinical signs, lower rectal temperatures, reduced viral shedding, greater white blood cell and platelet counts, and less severe pulmonary lesions than control animals. This was the first MLV combination vaccine to demonstrate efficacy against BVDV types 1 and 2, IBR, PI-3 and BRSV in calves 3-8 days of age. Copyright 2010 Elsevier Ltd. All rights reserved.

Ocular Tropism of Respiratory Viruses

Science.gov (United States)

Rota, Paul A.; Tumpey, Terrence M.

2013-01-01

SUMMARY Respiratory viruses (including adenovirus, influenza virus, respiratory syncytial virus, coronavirus, and rhinovirus) cause a broad spectrum of disease in humans, ranging from mild influenza-like symptoms to acute respiratory failure. While species D adenoviruses and subtype H7 influenza viruses are known to possess an ocular tropism, documented human ocular disease has been reported following infection with all principal respiratory viruses. In this review, we describe the anatomical proximity and cellular receptor distribution between ocular and respiratory tissues. All major respiratory viruses and their association with human ocular disease are discussed. Research utilizing in vitro and in vivo models to study the ability of respiratory viruses to use the eye as a portal of entry as well as a primary site of virus replication is highlighted. Identification of shared receptor-binding preferences, host responses, and laboratory modeling protocols among these viruses provides a needed bridge between clinical and laboratory studies of virus tropism. PMID:23471620

Understanding Ebola Virus Transmission

Directory of Open Access Journals (Sweden)

Seth Judson

2015-02-01

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.

Ganjam virus/Nairobi sheep disease virus induces a pro-inflammatory response in infected sheep

OpenAIRE

bin Tarif, Abid; Lasecka, Lidia; Holzer, Barbara; Baron, Michael D

2012-01-01

Abstract Partly due to climate change, and partly due to changes of human habitat occupation, the impact of tick-borne viruses is increasing. Nairobi sheep disease virus (NSDV) and Ganjam virus (GV) are two names for the same virus, which causes disease in sheep and goats and is currently known to be circulating in India and East Africa. The virus is transmitted by ixodid ticks and causes a severe hemorrhagic disease. We have developed a real-time PCR assay for the virus genome and validated ...

Zika Virus

Science.gov (United States)

... through blood transfusions. There have been outbreaks of Zika virus in the United States, Africa, Southeast Asia, the ... not travel to areas where there is a Zika virus outbreak. If you do decide to travel, first ...

Ganjam virus/Nairobi sheep disease virus induces a pro-inflammatory response in infected sheep

Directory of Open Access Journals (Sweden)

bin Tarif Abid

2012-10-01

Full Text Available Abstract Partly due to climate change, and partly due to changes of human habitat occupation, the impact of tick-borne viruses is increasing. Nairobi sheep disease virus (NSDV and Ganjam virus (GV are two names for the same virus, which causes disease in sheep and goats and is currently known to be circulating in India and East Africa. The virus is transmitted by ixodid ticks and causes a severe hemorrhagic disease. We have developed a real-time PCR assay for the virus genome and validated it in a pilot study of the pathogenicity induced by two different isolates of NSDV/GV. One isolate was highly adapted to tissue culture, grew in most cell lines tested, and was essentially apathogenic in sheep. The second isolate appeared to be poorly adapted to cell culture and retained pathogenicity in sheep. The real-time PCR assay for virus easily detected 4 copies or less of the viral genome, and allowed a quantitative measure of the virus in whole blood. Measurement of the changes in cytokine mRNAs showed similar changes to those observed in humans infected by the closely related virus Crimean Congo hemorrhagic fever virus.

Ganjam virus/Nairobi sheep disease virus induces a pro-inflammatory response in infected sheep.

Science.gov (United States)

Bin Tarif, Abid; Lasecka, Lidia; Holzer, Barbara; Baron, Michael D

2012-10-19

Partly due to climate change, and partly due to changes of human habitat occupation, the impact of tick-borne viruses is increasing. Nairobi sheep disease virus (NSDV) and Ganjam virus (GV) are two names for the same virus, which causes disease in sheep and goats and is currently known to be circulating in India and East Africa. The virus is transmitted by ixodid ticks and causes a severe hemorrhagic disease. We have developed a real-time PCR assay for the virus genome and validated it in a pilot study of the pathogenicity induced by two different isolates of NSDV/GV. One isolate was highly adapted to tissue culture, grew in most cell lines tested, and was essentially apathogenic in sheep. The second isolate appeared to be poorly adapted to cell culture and retained pathogenicity in sheep. The real-time PCR assay for virus easily detected 4 copies or less of the viral genome, and allowed a quantitative measure of the virus in whole blood. Measurement of the changes in cytokine mRNAs showed similar changes to those observed in humans infected by the closely related virus Crimean Congo hemorrhagic fever virus.

Transmission of Influenza A Viruses

Science.gov (United States)

Neumann, Gabriele; Kawaoka, Yoshihiro

2015-01-01

Influenza A viruses cause respiratory infections that range from asymptomatic to deadly in humans. Widespread outbreaks (pandemics) are attributable to ‘novel’ viruses that possess a viral hemagglutinin (HA) gene to which humans lack immunity. After a pandemic, these novel viruses form stable virus lineages in humans and circulate until they are replaced by other novel viruses. The factors and mechanisms that facilitate virus transmission among hosts and the establishment of novel lineages are not completely understood, but the HA and basic polymerase 2 (PB2) proteins are thought to play essential roles in these processes by enabling avian influenza viruses to infect mammals and replicate efficiently in their new host. Here, we summarize our current knowledge of the contributions of HA, PB2, and other viral components to virus transmission and the formation of new virus lineages. PMID:25812763

New frontiers in oncolytic viruses: optimizing and selecting for virus strains with improved efficacy

Directory of Open Access Journals (Sweden)

Lundstrom K

2018-02-01

Full Text Available Kenneth Lundstrom PanTherapeutics, Lutry, Switzerland Abstract: Oncolytic viruses have demonstrated selective replication and killing of tumor cells. Different types of oncolytic viruses – adenoviruses, alphaviruses, herpes simplex viruses, Newcastle disease viruses, rhabdoviruses, Coxsackie viruses, and vaccinia viruses – have been applied as either naturally occurring or engineered vectors. Numerous studies in animal-tumor models have demonstrated substantial tumor regression and prolonged survival rates. Moreover, clinical trials have confirmed good safety profiles and therapeutic efficacy for oncolytic viruses. Most encouragingly, the first cancer gene-therapy drug – Gendicine, based on oncolytic adenovirus type 5 – was approved in China. Likewise, a second-generation oncolytic herpes simplex virus-based drug for the treatment of melanoma has been registered in the US and Europe as talimogene laherparepvec. Keywords: immunotherapy, viral vectors, clinical trials, drug approval

Postmortem stability of Ebola virus.

Science.gov (United States)

Prescott, Joseph; Bushmaker, Trenton; Fischer, Robert; Miazgowicz, Kerri; Judson, Seth; Munster, Vincent J

2015-05-01

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 <7 days posteuthanasia; viral RNA was detectable for 10 weeks.

A Foxtail mosaic virus Vector for Virus-Induced Gene Silencing in Maize.

Science.gov (United States)

Mei, Yu; Zhang, Chunquan; Kernodle, Bliss M; Hill, John H; Whitham, Steven A

2016-06-01

Plant viruses have been widely used as vectors for foreign gene expression and virus-induced gene silencing (VIGS). A limited number of viruses have been developed into viral vectors for the purposes of gene expression or VIGS in monocotyledonous plants, and among these, the tripartite viruses Brome mosaic virus and Cucumber mosaic virus have been shown to induce VIGS in maize (Zea mays). We describe here a new DNA-based VIGS system derived from Foxtail mosaic virus (FoMV), a monopartite virus that is able to establish systemic infection and silencing of endogenous maize genes homologous to gene fragments inserted into the FoMV genome. To demonstrate VIGS applications of this FoMV vector system, four genes, phytoene desaturase (functions in carotenoid biosynthesis), lesion mimic22 (encodes a key enzyme of the porphyrin pathway), iojap (functions in plastid development), and brown midrib3 (caffeic acid O-methyltransferase), were silenced and characterized in the sweet corn line Golden × Bantam. Furthermore, we demonstrate that the FoMV infectious clone establishes systemic infection in maize inbred lines, sorghum (Sorghum bicolor), and green foxtail (Setaria viridis), indicating the potential wide applications of this viral vector system for functional genomics studies in maize and other monocots. © 2016 American Society of Plant Biologists. All Rights Reserved.

Efficient production of infectious viruses requires enzymatic activity of Epstein-Barr virus protein kinase.

Science.gov (United States)

Murata, Takayuki; Isomura, Hiroki; Yamashita, Yoriko; Toyama, Shigenori; Sato, Yoshitaka; Nakayama, Sanae; Kudoh, Ayumi; Iwahori, Satoko; Kanda, Teru; Tsurumi, Tatsuya

2009-06-20

The Epstein-Barr virus (EBV) BGLF4 gene product is the only protein kinase encoded by the virus genome. In order to elucidate its physiological roles in viral productive replication, we here established a BGLF4-knockout mutant and a revertant virus. While the levels of viral DNA replication of the deficient mutant were equivalent to those of the wild-type and the revertant, virus production was significantly impaired. Expression of the BGLF4 protein in trans fully complemented the low yield of the mutant virus, while expression of a kinase-dead (K102I) form of the protein failed to restore the virus titer. These results demonstrate that BGLF4 plays a significant role in production of infectious viruses and that the kinase activity is crucial.

Propagation Effect of a Virus Outbreak on a Network with Limited Anti-Virus Ability.

Directory of Open Access Journals (Sweden)

Yonghong Xu

Full Text Available This paper describes a new computer virus spreading model which takes into account the possibility of a virus outbreak on a network with limited anti-virus ability. Then, the model is investigated for the existence of equilibria and their stabilities are proved and illustrated. Moreover, it is found that these two factors are not only relative to the threshold value determining whether the virus becomes extinct or not, but that they are also relative to the virus epidemic levels. Theoretical and experimental results indicate that, in some ways, it would be practically possible to eradicate the virus or suppress its prevalence below a suitable level. Consequently, some suggestions are proposed that may help eradicate or suppress virus propagation over a real computer network.

An introduction to computer viruses

Energy Technology Data Exchange (ETDEWEB)

Brown, D.R.

1992-03-01

This report on computer viruses is based upon a thesis written for the Master of Science degree in Computer Science from the University of Tennessee in December 1989 by David R. Brown. This thesis is entitled An Analysis of Computer Virus Construction, Proliferation, and Control and is available through the University of Tennessee Library. This paper contains an overview of the computer virus arena that can help the reader to evaluate the threat that computer viruses pose. The extent of this threat can only be determined by evaluating many different factors. These factors include the relative ease with which a computer virus can be written, the motivation involved in writing a computer virus, the damage and overhead incurred by infected systems, and the legal implications of computer viruses, among others. Based upon the research, the development of a computer virus seems to require more persistence than technical expertise. This is a frightening proclamation to the computing community. The education of computer professionals to the dangers that viruses pose to the welfare of the computing industry as a whole is stressed as a means of inhibiting the current proliferation of computer virus programs. Recommendations are made to assist computer users in preventing infection by computer viruses. These recommendations support solid general computer security practices as a means of combating computer viruses.

Viruses infecting marine molluscs.

Science.gov (United States)

Arzul, Isabelle; Corbeil, Serge; Morga, Benjamin; Renault, Tristan

2017-07-01

Although a wide range of viruses have been reported in marine molluscs, most of these reports rely on ultrastructural examination and few of these viruses have been fully characterized. The lack of marine mollusc cell lines restricts virus isolation capacities and subsequent characterization works. Our current knowledge is mostly restricted to viruses affecting farmed species such as oysters Crassostrea gigas, abalone Haliotis diversicolor supertexta or the scallop Chlamys farreri. Molecular approaches which are needed to identify virus affiliation have been carried out for a small number of viruses, most of them belonging to the Herpesviridae and birnaviridae families. These last years, the use of New Generation Sequencing approach has allowed increasing the number of sequenced viral genomes and has improved our capacity to investigate the diversity of viruses infecting marine molluscs. This new information has in turn allowed designing more efficient diagnostic tools. Moreover, the development of experimental infection protocols has answered some questions regarding the pathogenesis of these viruses and their interactions with their hosts. Control and management of viral diseases in molluscs mostly involve active surveillance, implementation of effective bio security measures and development of breeding programs. However factors triggering pathogen development and the life cycle and status of the viruses outside their mollusc hosts still need further investigations. Copyright © 2017 Elsevier Inc. All rights reserved.

Coinfection with Epstein–Barr Virus (EBV), Human Papilloma Virus (HPV) and Polyoma BK Virus (BKPyV) in Laryngeal, Oropharyngeal and Oral Cavity Cancer

OpenAIRE

Drop, Bartłomiej; Strycharz-Dudziak, Małgorzata; Kliszczewska, Ewa; Polz-Dacewicz, Małgorzata

2017-01-01

Most research providing evidence for the role of oncogenic viruses in head and neck squamous cell carcinoma (SCC) development is focused on one type of virus without analyzing possible interactions between two or more types of viruses. The aim of this study was to analyse the prevalence of co-infection with human papillomavirus (HPV), Epstein–Barr virus (EBV) and polyoma BK virus (BKPyV) in oral, oropharyngeal and laryngeal squamous cell carcinomas in Polish patients. The correlations between...

RNA viruses in the sea.

Science.gov (United States)

Lang, Andrew S; Rise, Matthew L; Culley, Alexander I; Steward, Grieg F

2009-03-01

Viruses are ubiquitous in the sea and appear to outnumber all other forms of marine life by at least an order of magnitude. Through selective infection, viruses influence nutrient cycling, community structure, and evolution in the ocean. Over the past 20 years we have learned a great deal about the diversity and ecology of the viruses that constitute the marine virioplankton, but until recently the emphasis has been on DNA viruses. Along with expanding knowledge about RNA viruses that infect important marine animals, recent isolations of RNA viruses that infect single-celled eukaryotes and molecular analyses of the RNA virioplankton have revealed that marine RNA viruses are novel, widespread, and genetically diverse. Discoveries in marine RNA virology are broadening our understanding of the biology, ecology, and evolution of viruses, and the epidemiology of viral diseases, but there is still much that we need to learn about the ecology and diversity of RNA viruses before we can fully appreciate their contributions to the dynamics of marine ecosystems. As a step toward making sense of how RNA viruses contribute to the extraordinary viral diversity in the sea, we summarize in this review what is currently known about RNA viruses that infect marine organisms.

Reverse genetics of measles virus and resulting multivalent recombinant vaccines: applications of recombinant measles viruses.

Science.gov (United States)

Billeter, M A; Naim, H Y; Udem, S A

2009-01-01

An overview is given on the development of technologies to allow reverse genetics of RNA viruses, i.e., the rescue of viruses from cDNA, with emphasis on nonsegmented negative-strand RNA viruses (Mononegavirales), as exemplified for measles virus (MV). Primarily, these technologies allowed site-directed mutagenesis, enabling important insights into a variety of aspects of the biology of these viruses. Concomitantly, foreign coding sequences were inserted to (a) allow localization of virus replication in vivo through marker gene expression, (b) develop candidate multivalent vaccines against measles and other pathogens, and (c) create candidate oncolytic viruses. The vector use of these viruses was experimentally encouraged by the pronounced genetic stability of the recombinants unexpected for RNA viruses, and by the high load of insertable genetic material, in excess of 6 kb. The known assets, such as the small genome size of the vector in comparison to DNA viruses proposed as vectors, the extensive clinical experience of attenuated MV as vaccine with a proven record of high safety and efficacy, and the low production cost per vaccination dose are thus favorably complemented.

Schmallenberg Virus

Indian Academy of Sciences (India)

IAS Admin

explore the potential of this infection crossing the species barrier and thereby .... The virus targets mainly the brain of the unborn animal resulting in neurological ... The virus is located in the blood of the adult infected animal or in the central ...

A combination in-ovo vaccine for avian influenza virus and Newcastle disease virus.

Science.gov (United States)

Steel, John; Burmakina, Svetlana V; Thomas, Colleen; Spackman, Erica; García-Sastre, Adolfo; Swayne, David E; Palese, Peter

2008-01-24

The protection of poultry from H5N1 highly pathogenic avian influenza A (HPAI) and Newcastle disease virus (NDV) can be achieved through vaccination, as part of a broader disease control strategy. We have previously generated a recombinant influenza virus expressing, (i) an H5 hemagglutinin protein, modified by the removal of the polybasic cleavage peptide and (ii) the ectodomain of the NDV hemagglutinin-neuraminidase (HN) protein in the place of the ectodomain of influenza neuraminidase (Park MS, et al. Proc Natl Acad Sci USA 2006;103(21):8203-8). Here we show this virus is attenuated in primary normal human bronchial epithelial (NHBE) cell culture, and demonstrate protection of C57BL/6 mice from lethal challenge with an H5 HA-containing influenza virus through immunisation with the recombinant virus. In addition, in-ovo vaccination of 18-day-old embryonated chicken eggs provided 90% and 80% protection against highly stringent lethal challenge by NDV and H5N1 virus, respectively. We propose that this virus has potential as a safe in-ovo live, attenuated, bivalent avian influenza and Newcastle disease virus vaccine.

Evaluation of the suitability of a plant virus, pepper mild mottle virus, as a surrogate of human enteric viruses for assessment of the efficacy of coagulation-rapid sand filtration to remove those viruses.

Science.gov (United States)

Shirasaki, N; Matsushita, T; Matsui, Y; Yamashita, R

2018-02-01

Here, we evaluated the removal of three representative human enteric viruses - adenovirus (AdV) type 40, coxsackievirus (CV) B5, and hepatitis A virus (HAV) IB - and one surrogate of human caliciviruses - murine norovirus (MNV) type 1 - by coagulation-rapid sand filtration, using water samples from eight water sources for drinking water treatment plants in Japan. The removal ratios of a plant virus (pepper mild mottle virus; PMMoV) and two bacteriophages (MS2 and φX174) were compared with the removal ratios of human enteric viruses to assess the suitability of PMMoV, MS2, and φX174 as surrogates for human enteric viruses. The removal ratios of AdV, CV, HAV, and MNV, evaluated via the real-time polymerase chain reaction (PCR) method, were 0.8-2.5-log 10 when commercially available polyaluminum chloride (PACl, basicity 1.5) and virgin silica sand were used as the coagulant and filter medium, respectively. The type of coagulant affected the virus removal efficiency, but the age of silica sand used in the rapid sand filtration did not. Coagulation-rapid sand filtration with non-sulfated, high-basicity PACls (basicity 2.1 or 2.5) removed viruses more efficiently than the other aluminum-based coagulants. The removal ratios of MS2 were sometimes higher than those of the three human enteric viruses and MNV, whereas the removal ratios of φX174 tended to be smaller than those of the three human enteric viruses and MNV. In contrast, the removal ratios of PMMoV were similar to and strongly correlated with those of the three human enteric viruses and MNV. Thus, PMMoV appears to be a suitable surrogate for human enteric viruses for the assessment of the efficacy of coagulation-rapid sand filtration to remove viruses. Copyright © 2017 Elsevier Ltd. All rights reserved.

An inactivated whole-virus porcine parvovirus vaccine protects pigs against disease but does not prevent virus shedding even after homologous virus challenge.

Science.gov (United States)

Foerster, Tessa; Streck, André Felipe; Speck, Stephanie; Selbitz, Hans-Joachim; Lindner, Thomas; Truyen, Uwe

2016-06-01

Inactivated whole-virus vaccines against porcine parvovirus (PPV) can prevent disease but not infection and virus shedding after heterologous virus challenge. Here, we showed that the same is true for a homologous challenge. Pregnant sows were vaccinated with an experimental inactivated vaccine based on PPV strain 27a. They were challenged on day 40 of gestation with the virulent porcine parvovirus PPV-27a from which the vaccine was prepared (homologous challenge). On day 90 of gestation, the fetuses from vaccinated sows were protected against disease, while the fetuses of the non-vaccinated sows (control group) exhibited signs of parvovirus disease. All gilts, whether vaccinated or not vaccinated, showed a boost of PPV-specific antibodies indicative of virus infection and replication. Low DNA copy numbers, but not infectious virus, could be demonstrated in nasal or rectal swabs of immunized sows, but high copy numbers of challenge virus DNA as well as infectious virus could both be demonstrated in non-vaccinated sows.

Dinucleotide Composition in Animal RNA Viruses Is Shaped More by Virus Family than by Host Species.

Science.gov (United States)

Di Giallonardo, Francesca; Schlub, Timothy E; Shi, Mang; Holmes, Edward C

2017-04-15

Viruses use the cellular machinery of their hosts for replication. It has therefore been proposed that the nucleotide and dinucleotide compositions of viruses should match those of their host species. If this is upheld, it may then be possible to use dinucleotide composition to predict the true host species of viruses sampled in metagenomic surveys. However, it is also clear that different taxonomic groups of viruses tend to have distinctive patterns of dinucleotide composition that may be independent of host species. To determine the relative strength of the effect of host versus virus family in shaping dinucleotide composition, we performed a comparative analysis of 20 RNA virus families from 15 host groupings, spanning two animal phyla and more than 900 virus species. In particular, we determined the odds ratios for the 16 possible dinucleotides and performed a discriminant analysis to evaluate the capability of virus dinucleotide composition to predict the correct virus family or host taxon from which it was isolated. Notably, while 81% of the data analyzed here were predicted to the correct virus family, only 62% of these data were predicted to their correct subphylum/class host and a mere 32% to their correct mammalian order. Similarly, dinucleotide composition has a weak predictive power for different hosts within individual virus families. We therefore conclude that dinucleotide composition is generally uniform within a virus family but less well reflects that of its host species. This has obvious implications for attempts to accurately predict host species from virus genome sequences alone. IMPORTANCE Determining the processes that shape virus genomes is central to understanding virus evolution and emergence. One question of particular importance is why nucleotide and dinucleotide frequencies differ so markedly between viruses. In particular, it is currently unclear whether host species or virus family has the biggest impact on dinucleotide frequencies and

Monoclonal antibodies against plant viruses

International Nuclear Information System (INIS)

Sandler, E.; Dietzgen, R.G.

1984-01-01

Ever since antigenic properties of plant viruses were discovered antisera have been raised and used for plant virus diagnosis and for the analysis of virus structure as well. From the early qualitative diagnosis method of precipitating the virus in clarified sap of an infected plant and the first quantitative application of the precipitin test vast progress has been made with regard to the development of highly sensitive and highly quantitative methods for virus detection. Of equal importance was the improvement of methods for separating virus from host cell components since the specificity of antisera raised against a virus could be increased by using an antigen for immunization highly concentrated and largely freed from contaminating host substances. The introduction of the enzyme-linked immunosorbent assay (ELISA) into plant virology allows detection of virus in nanogram quantities. Still, the conventionally raised antisera, no matter how pure an antigen was used for immunization, are polyclonal. They contain products of thousands of different antibody-secreting plasma cell clones which can be directed against all antigenic determinants (epitopes) of the virus, but also against antigens of the host plant that may not have been entirely separated from the immunizing virus during the purification procedure. Even after cross adsorption of polyclonal antisera some residual heterogeneity can be expected to remain. Within these boundaries the information gained with polyclonal antisera on virus structure and on virus diagnosis has to be interpreted

Zika Virus and Pregnancy

Science.gov (United States)

... Management Education & Events Advocacy For Patients About ACOG Zika Virus and Pregnancy Home For Patients Zika Virus and ... Patient Education Pamphlets - Spanish Share: PEV002, September 2016 Zika Virus and Pregnancy There are risks to your fetus ...

Zika Virus

Science.gov (United States)

... with facebook share with twitter share with linkedin Zika Virus Credit: NIAID A female Aedes mosquito. This type of mosquito can transmit Zika, ... transmitted to humans through the bite of infected Aedes aegypti mosquitoes. Zika virus can be transmitted from an infected pregnant woman ...

CHANDIPURA VIRUS

Indian Academy of Sciences (India)

First page Back Continue Last page Overview Graphics. CHANDIPURA VIRUS. First isolated from a village called Chandipura near Nagpur in 1965 in India. Belongs to rhabdoviridae family. Used as a Model System to study RNA virus multiplication in the infected cell at molecular level. Notes:

Clinical and biological differences between recurrent herpes simplex virus and varicella-zoster virus infections

International Nuclear Information System (INIS)

Straus, S.E.

1989-01-01

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

Zika Virus and Pregnancy

Medline Plus

Full Text Available ... Management Education & Events Advocacy For Patients About ACOG Zika Virus and Pregnancy Home For Patients Zika Virus ... Patient Education Pamphlets - Spanish Share: PEV002, September 2016 Zika Virus and Pregnancy There are risks to your ...

Zika Virus and Pregnancy

Medline Plus

Full Text Available ... Education & Events Advocacy For Patients About ACOG Zika Virus and Pregnancy Home For Patients Zika Virus and ... Education Pamphlets - Spanish Share: PEV002, September 2016 Zika Virus and Pregnancy There are risks to your fetus ...

What's West Nile Virus?

Science.gov (United States)

... for Educators Search English Español What's West Nile Virus? KidsHealth / For Kids / What's West Nile Virus? Print en español ¿Qué es el Virus del Nilo Occidental? What exactly is the West ...

Zika Virus and Pregnancy

Medline Plus

Full Text Available ... Advocacy For Patients About ACOG Zika Virus and Pregnancy Home For Patients Zika Virus and Pregnancy Page ... Spanish Share: PEV002, September 2016 Zika Virus and Pregnancy There are risks to your fetus if you ...

Human Immunodeficiency Virus and Hepatitis C Virus Co-infection ...

African Journals Online (AJOL)

Human Immunodeficiency Virus and Hepatitis C Virus Co-infection in Cameroon: Investigation of the Genetic Diversity and Virulent ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING AJOL · RESOURCES ... DNA sequencing, and bioinformatics tools for sequence management and analysis.

Virus world as an evolutionary network of viruses and capsidless selfish elements.

Science.gov (United States)

Koonin, Eugene V; Dolja, Valerian V

2014-06-01

Viruses were defined as one of the two principal types of organisms in the biosphere, namely, as capsid-encoding organisms in contrast to ribosome-encoding organisms, i.e., all cellular life forms. Structurally similar, apparently homologous capsids are present in a huge variety of icosahedral viruses that infect bacteria, archaea, and eukaryotes. These findings prompted the concept of the capsid as the virus "self" that defines the identity of deep, ancient viral lineages. However, several other widespread viral "hallmark genes" encode key components of the viral replication apparatus (such as polymerases and helicases) and combine with different capsid proteins, given the inherently modular character of viral evolution. Furthermore, diverse, widespread, capsidless selfish genetic elements, such as plasmids and various types of transposons, share hallmark genes with viruses. Viruses appear to have evolved from capsidless selfish elements, and vice versa, on multiple occasions during evolution. At the earliest, precellular stage of life's evolution, capsidless genetic parasites most likely emerged first and subsequently gave rise to different classes of viruses. In this review, we develop the concept of a greater virus world which forms an evolutionary network that is held together by shared conserved genes and includes both bona fide capsid-encoding viruses and different classes of capsidless replicons. Theoretical studies indicate that selfish replicons (genetic parasites) inevitably emerge in any sufficiently complex evolving ensemble of replicators. Therefore, the key signature of the greater virus world is not the presence of a capsid but rather genetic, informational parasitism itself, i.e., various degrees of reliance on the information processing systems of the host. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Replacement of Murine Leukemia Virus Readthrough Mechanism by Human Immunodeficiency Virus Frameshift Allows Synthesis of Viral Proteins and Virus Replication

Science.gov (United States)

Brunelle, Marie-Noëlle; Brakier-Gingras, Léa; Lemay, Guy

2003-01-01

Retroviruses use unusual recoding strategies to synthesize the Gag-Pol polyprotein precursor of viral enzymes. In human immunodeficiency virus, ribosomes translating full-length viral RNA can shift back by 1 nucleotide at a specific site defined by the presence of both a slippery sequence and a downstream stimulatory element made of an extensive secondary structure. This so-called frameshift mechanism could become a target for the development of novel antiviral strategies. A different recoding strategy is used by other retroviruses, such as murine leukemia viruses, to synthesize the Gag-Pol precursor; in this case, a stop codon is suppressed in a readthrough process, again due to the presence of a specific structure adopted by the mRNA. Development of antiframeshift agents will greatly benefit from the availability of a simple animal and virus model. For this purpose, the murine leukemia virus readthrough region was rendered inactive by mutagenesis and the frameshift region of human immunodeficiency virus was inserted to generate a chimeric provirus. This substitution of readthrough by frameshift allows the synthesis of viral proteins, and the chimeric provirus sequence was found to generate infectious viruses. This system could be a most interesting alternative to study ribosomal frameshift in the context of a virus amenable to the use of a simple animal model. PMID:12584361

[Mumps vaccine virus transmission].

Science.gov (United States)

Otrashevskaia, E V; Kulak, M V; Otrashevskaia, A V; Karpov, I A; Fisenko, E G; Ignat'ev, G M

2013-01-01

In this work we report the mumps vaccine virus shedding based on the laboratory confirmed cases of the mumps virus (MuV) infection. The likely epidemiological sources of the transmitted mumps virus were children who were recently vaccinated with the mumps vaccine containing Leningrad-Zagreb or Leningrad-3 MuV. The etiology of the described cases of the horizontal transmission of both mumps vaccine viruses was confirmed by PCR with the sequential restriction analysis.

Zika Virus and Pregnancy

Medline Plus

Full Text Available ... Management Education & Events Advocacy For Patients About ACOG Zika Virus and Pregnancy Home For Patients Zika Virus and ... Patient Education Pamphlets - Spanish Share: PEV002, September 2016 Zika Virus and Pregnancy There are risks to your fetus ...

Zika Virus Fact Sheet

Science.gov (United States)

... is caused by a virus transmitted primarily by Aedes mosquitoes. People with Zika virus disease can have symptoms including mild fever, skin ... framework. Q&A: Zika virus and complication ... mosquito from the Aedes genus, mainly Aedes aegypti in tropical regions. Aedes ...

Computer Viruses: An Overview.

Science.gov (United States)

Marmion, Dan

1990-01-01

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)

An infectious bat-derived chimeric influenza virus harbouring the entry machinery of an influenza A virus.

Science.gov (United States)

Juozapaitis, Mindaugas; Aguiar Moreira, Étori; Mena, Ignacio; Giese, Sebastian; Riegger, David; Pohlmann, Anne; Höper, Dirk; Zimmer, Gert; Beer, Martin; García-Sastre, Adolfo; Schwemmle, Martin

2014-07-23

In 2012, the complete genomic sequence of a new and potentially harmful influenza A-like virus from bats (H17N10) was identified. However, infectious influenza virus was neither isolated from infected bats nor reconstituted, impeding further characterization of this virus. Here we show the generation of an infectious chimeric virus containing six out of the eight bat virus genes, with the remaining two genes encoding the haemagglutinin and neuraminidase proteins of a prototypic influenza A virus. This engineered virus replicates well in a broad range of mammalian cell cultures, human primary airway epithelial cells and mice, but poorly in avian cells and chicken embryos without further adaptation. Importantly, the bat chimeric virus is unable to reassort with other influenza A viruses. Although our data do not exclude the possibility of zoonotic transmission of bat influenza viruses into the human population, they indicate that multiple barriers exist that makes this an unlikely event.

Zika virus infection.

Science.gov (United States)

Pougnet, Laurence; Thill, Chloé; Pougnet, Richard; Auvinet, Henri; Giacardi, Christophe; Drouillard, Isabelle

2016-12-01

A 21-year old woman from New-Caledonia had 40 ̊C fever with vomiting, arthralgia, myalgia, and measles-like rash. Etiological analyses showed primary infection with Zika virus. Because of severe clinical presentation, she was hospitalized in the intensive care unit of the Brest military Hospital. Zika virus is mainly transmitted by Aedes mosquitoes. If they settle in Metropolitan France, Zika virus might also spread there.

Comparative analysis of rabbit hemorrhagic disease virus (RHDV) and new RHDV2 virus antigenicity, using specific virus-like particles.

Science.gov (United States)

Bárcena, Juan; Guerra, Beatriz; Angulo, Iván; González, Julia; Valcárcel, Félix; Mata, Carlos P; Castón, José R; Blanco, Esther; Alejo, Alí

2015-09-24

In 2010 a new Lagovirus related to rabbit haemorrhagic disease virus (RHDV) emerged in France and has since rapidly spread throughout domestic and wild rabbit populations of several European countries. The new virus, termed RHDV2, exhibits distinctive genetic, antigenic and pathogenic features. Notably, RHDV2 kills rabbits previously vaccinated with RHDV vaccines. Here we report for the first time the generation and characterization of RHDV2-specific virus-like particles (VLPs). Our results further confirmed the differential antigenic properties exhibited by RHDV and RHDV2, highlighting the need of using RHDV2-specific diagnostic assays to monitor the spread of this new virus.

Structural and Functional Studies on the Fusion and Attachment Envelope Glycoproteins of Nipah Virus and Hendra Virus

Science.gov (United States)

2003-01-01

including measles virus (MeV), mumps virus, Sendai virus (SeV), Newcastle disease virus (NDV), rinderpest virus, canine distemper virus (CDV), human...Institute of Health, Bethesda, MD. Hut 102, MT2, MT4, and CEM human T cell lines were provided by Chou-Zen Giam, USUHS, Bethesda, MD. The human osteosarcoma

Single Assay Detection of Acute Bee Paralysis Virus, Kashmir Bee Virus and Israeli Acute Paralysis Virus

DEFF Research Database (Denmark)

Francis, Roy Mathew; Kryger, Per

2012-01-01

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-PCR ......-PCR reaction saving time and money. The primers are located in the predicted overlapping gene (pog/ORFX) which is highly conserved across ABPV, KBV, IAPV and other dicistroviruses of social insects. This study has also identified the first case of IAPV in Denmark....

Structure of viruses: a short history.

Science.gov (United States)

Rossmann, Michael G

2013-05-01

This review is a partially personal account of the discovery of virus structure and its implication for virus function. Although I have endeavored to cover all aspects of structural virology and to acknowledge relevant individuals, I know that I have favored taking examples from my own experience in telling this story. I am anxious to apologize to all those who I might have unintentionally offended by omitting their work. The first knowledge of virus structure was a result of Stanley's studies of tobacco mosaic virus (TMV) and the subsequent X-ray fiber diffraction analysis by Bernal and Fankuchen in the 1930s. At about the same time it became apparent that crystals of small RNA plant and animal viruses could diffract X-rays, demonstrating that viruses must have distinct and unique structures. More advances were made in the 1950s with the realization by Watson and Crick that viruses might have icosahedral symmetry. With the improvement of experimental and computational techniques in the 1970s, it became possible to determine the three-dimensional, near-atomic resolution structures of some small icosahedral plant and animal RNA viruses. It was a great surprise that the protecting capsids of the first virus structures to be determined had the same architecture. The capsid proteins of these viruses all had a 'jelly-roll' fold and, furthermore, the organization of the capsid protein in the virus were similar, suggesting a common ancestral virus from which many of today's viruses have evolved. By this time a more detailed structure of TMV had also been established, but both the architecture and capsid protein fold were quite different to that of the icosahedral viruses. The small icosahedral RNA virus structures were also informative of how and where cellular receptors, anti-viral compounds, and neutralizing antibodies bound to these viruses. However, larger lipid membrane enveloped viruses did not form sufficiently ordered crystals to obtain good X-ray diffraction

Computer Viruses: Pathology and Detection.

Science.gov (United States)

Maxwell, John R.; Lamon, William E.

1992-01-01

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)

Yeast for virus research

Science.gov (United States)

Zhao, Richard Yuqi

2017-01-01

Budding yeast (Saccharomyces cerevisiae) and fission yeast (Schizosaccharomyces pombe) are two popular model organisms for virus research. They are natural hosts for viruses as they carry their own indigenous viruses. Both yeasts have been used for studies of plant, animal and human viruses. Many positive sense (+) RNA viruses and some DNA viruses replicate with various levels in yeasts, thus allowing study of those viral activities during viral life cycle. Yeasts are single cell eukaryotic organisms. Hence, many of the fundamental cellular functions such as cell cycle regulation or programed cell death are highly conserved from yeasts to higher eukaryotes. Therefore, they are particularly suited to study the impact of those viral activities on related cellular activities during virus-host interactions. Yeasts present many unique advantages in virus research over high eukaryotes. Yeast cells are easy to maintain in the laboratory with relative short doubling time. They are non-biohazardous, genetically amendable with small genomes that permit genome-wide analysis of virologic and cellular functions. In this review, similarities and differences of these two yeasts are described. Studies of virologic activities such as viral translation, viral replication and genome-wide study of virus-cell interactions in yeasts are highlighted. Impacts of viral proteins on basic cellular functions such as cell cycle regulation and programed cell death are discussed. Potential applications of using yeasts as hosts to carry out functional analysis of small viral genome and to develop high throughput drug screening platform for the discovery of antiviral drugs are presented. PMID:29082230

Special Issue: Honey Bee Viruses

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Sebastian Gisder

2015-10-01

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.

Special Issue: Honey Bee Viruses

Science.gov (United States)

Gisder, Sebastian; Genersch, Elke

2015-01-01

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. PMID:26702462

Diversity of viruses in Ixodes ricinus, and characterization of a neurotropic strain of Eyach virus.

Science.gov (United States)

Moutailler, S; Popovici, I; Devillers, E; Vayssier-Taussat, M; Eloit, M

2016-05-01

Ticks transmit more pathogens-including bacteria, parasites and viruses-than any other arthropod vector. Although the epidemiological status of many tick-borne bacteria is very well characterized, tick-borne viruses are still relatively under-studied. Recently, several novel tick-borne viruses have been isolated from human febrile illnesses following tick bites, indicating the existence of other potential new and unknown tick-borne viruses. We used high-throughput sequencing to analyse the virome of Ixodes ricinus, the main vector of tick-borne pathogens in Europe. The majority of collected viral sequences were assigned to two potentially novel Nairovirus and Phlebovirus viruses, with prevalence rates ranging from 3.95% to 23.88% in adults and estimated to be between 0.14% and 72.16% in nymphs. These viruses could not be isolated from the brains of inoculated immunocompromised mice, perhaps indicating that they are unable to infect vertebrates. Within the I. ricinus virome, we also identified contigs with >90% identity to the known Eyach virus. Initially isolated in the 1980s, this virus was indirectly associated with human disease, but had never been extensively studied. Eyach virus prevalence varied between 0.07% and 5.26% in ticks from the French Ardennes and Alsace regions. Eyach virus was successfully isolated following intracerebral inoculation of immunocompromised mice with Eyach virus-positive tick extracts. This virus was also able to multiply and persist in the blood of immunocompetent mice inoculated by intraperitoneal injection, and caused brain infections in three of nine juveniles, without any obvious deleterious effects.

Zika Virus: An Emerging Worldwide Threat

OpenAIRE

Irfan A. Rather; Jameel B. Lone; Vivek K. Bajpai; Woon K. Paek; Jeongheui Lim

2017-01-01

ZIKA virus (ZIKV) poses a severe threat to the world. Recent outbreaks of ZIKV after 2007 along with its quick transmission have made this virus a matter of international concern. The virus shows symptoms that are similar to those caused in the wake of dengue virus (DENV) and other flaviviruses, which makes it difficult to discern the viral infection. Diagnosis is further complicated as the virus cross-reacts with antibodies of other viruses. Currently, molecular diagnosis of the virus is bei...

How hepatitis D virus can hinder the control of hepatitis B virus.

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Maria Xiridou

Full Text Available BACKGROUND: Hepatitis D (or hepatitis delta virus is a defective virus that relies on hepatitis B virus (HBV for transmission; infection with hepatitis D can occur only as coinfection with HBV or superinfection of an existing HBV infection. Because of the bond between the two viruses, control measures for HBV may have also affected the spread of hepatitis D, as evidenced by the decline of hepatitis D in recent years. Since the presence of hepatitis D is associated with suppressed HBV replication and possibly infectivity, it is reasonable to speculate that hepatitis D may facilitate the control of HBV. METHODOLOGY AND PRINCIPAL FINDINGS: We introduced a mathematical model for the transmission of HBV and hepatitis D, where individuals with dual HBV and hepatitis D infection transmit both viruses. We calculated the reproduction numbers of single HBV infections and dual HBV and hepatitis D infections and examined the endemic prevalences of the two viruses. The results show that hepatitis D virus modulates not only the severity of the HBV epidemic, but also the impact of interventions for HBV. Surprisingly we find that the presence of hepatitis D virus may hamper the eradication of HBV. Interventions that aim to reduce the basic reproduction number of HBV below one may not be sufficient to eradicate the virus, as control of HBV depends also on the reproduction numbers of dual infections. CONCLUSIONS AND SIGNIFICANCE: For populations where hepatitis D is endemic, plans for control programs ignoring the presence of hepatitis D may underestimate the HBV epidemic and produce overoptimistic results. The current HBV surveillance should be augmented with monitoring of hepatitis D, in order to improve accuracy of the monitoring and the efficacy of control measures.

Archaeal viruses of the sulfolobales

DEFF Research Database (Denmark)

Erdmann, Susanne; Garrett, Roger Antony

2015-01-01

in 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...... with an environmental virus mixture isolated from Yellowstone National Park (Erdmann and Garrett, Mol Microbiol 85:1044-1056, 2012). Experimental studies of isolated genetic elements from this mixture revealed that SMV1 (S ulfolobus Monocauda Virus 1), a tailed spindle-shaped virus, can induce spacer acquisition...... and the techniques used both to infect laboratory strains with these virus mixtures and to obtain purified virus particles. Secondly, we present the experimental conditions required for activating SMV1-induced spacer acquisition in two different Sulfolobus species....

Seasonal and pandemic human influenza viruses attach better to human upper respiratory tract epithelium than avian influenza viruses.

Science.gov (United States)

van Riel, Debby; den Bakker, Michael A; Leijten, Lonneke M E; Chutinimitkul, Salin; Munster, Vincent J; de Wit, Emmie; Rimmelzwaan, Guus F; Fouchier, Ron A M; Osterhaus, Albert D M E; Kuiken, Thijs

2010-04-01

Influenza viruses vary markedly in their efficiency of human-to-human transmission. This variation has been speculated to be determined in part by the tropism of influenza virus for the human upper respiratory tract. To study this tropism, we determined the pattern of virus attachment by virus histochemistry of three human and three avian influenza viruses in human nasal septum, conchae, nasopharynx, paranasal sinuses, and larynx. We found that the human influenza viruses-two seasonal influenza viruses and pandemic H1N1 virus-attached abundantly to ciliated epithelial cells and goblet cells throughout the upper respiratory tract. In contrast, the avian influenza viruses, including the highly pathogenic H5N1 virus, attached only rarely to epithelial cells or goblet cells. Both human and avian viruses attached occasionally to cells of the submucosal glands. The pattern of virus attachment was similar among the different sites of the human upper respiratory tract for each virus tested. We conclude that influenza viruses that are transmitted efficiently among humans attach abundantly to human upper respiratory tract, whereas inefficiently transmitted influenza viruses attach rarely. These results suggest that the ability of an influenza virus to attach to human upper respiratory tract is a critical factor for efficient transmission in the human population.

Mutagenesis-mediated virus extinction: virus-dependent effect of viral load on sensitivity to lethal defection.

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Héctor Moreno

Full Text Available BACKGROUND: Lethal mutagenesis is a transition towards virus extinction mediated by enhanced mutation rates during viral genome replication, and it is currently under investigation as a potential new antiviral strategy. Viral load and virus fitness are known to influence virus extinction. Here we examine the effect or the multiplicity of infection (MOI on progeny production of several RNA viruses under enhanced mutagenesis. RESULTS: The effect of the mutagenic base analogue 5-fluorouracil (FU on the replication of the arenavirus lymphocytic choriomeningitis virus (LCMV can result either in inhibition of progeny production and virus extinction in infections carried out at low multiplicity of infection (MOI, or in a moderate titer decrease without extinction at high MOI. The effect of the MOI is similar for LCMV and vesicular stomatitis virus (VSV, but minimal or absent for the picornaviruses foot-and-mouth disease virus (FMDV and encephalomyocarditis virus (EMCV. The increase in mutation frequency and Shannon entropy (mutant spectrum complexity as a result of virus passage in the presence of FU was more accentuated at low MOI for LCMV and VSV, and at high MOI for FMDV and EMCV. We present an extension of the lethal defection model that agrees with the experimental results. CONCLUSIONS: (i Low infecting load favoured the extinction of negative strand viruses, LCMV or VSV, with an increase of mutant spectrum complexity. (ii This behaviour is not observed in RNA positive strand viruses, FMDV or EMCV. (iii The accumulation of defector genomes may underlie the MOI-dependent behaviour. (iv LCMV coinfections are allowed but superinfection is strongly restricted in BHK-21 cells. (v The dissimilar effects of the MOI on the efficiency of mutagenic-based extinction of different RNA viruses can have implications for the design of antiviral protocols based on lethal mutagenesis, presently under development.

Coinfection of hepatitis E virus and other hepatitis virus in Colombia and its genotypic characterization.

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Peláez, Dioselina; Martínez-Vargas, Daniel; Escalante-Mora, Martha; Palacios-Vivero, Mariel; Contreras-Gómez, Lady

2015-12-04

Hepatitis E virus has emerged as a public health problem, particularly in developing countries. The four genotypes identified in mammals include the G3 found in indigenous hepatitis in countries and regions with high porcine population, and the G1, associated with maternal deaths.  To determine coinfection by hepatitis E virus and the circulating genotypes in Colombia in 1,097 samples using serological markers for hepatitis A, B and C.  Serum samples of 1,097 patients from different regions of Colombia stored at the Laboratorio de Virología of the Instituto Nacional de Salud were selected to detect IgG and IgM anti-hepatitis E virus antibodies. The viral genomes of positive samples were amplified by RT-PCR, and the products were sequenced and phylogenetically analyzed by comparing ORF2 sequences deposited in the GenBank.  IgG anti-hepatitis E virus antibodies were found in 278 samples, IgM in 62, and both markers in 64. Hepatitis E virus and hepatitis A virus coinfection determined by IgG anti-hepatitis E virus was 33.6% and 16.1% by IgM; hepatitis E virus and hepatitis B virus coinfection was 23.4% and 8.1%, and hepatitis E virus and hepatitis C virus coinfection was 35.4% and 5.83%, respectively. Among the 52 positive samples by PCR nine were sequenced and grouped within genotype 3A of the American porcine strain.  The highest seropositivity was observed for hepatitis A and E. The incidence of hepatitis E virus coinfection with other hepatotropic viruses indicated that this pathogen is more frequent than expected. The circulation of genotype 3A implies that this disease may occur in outbreaks and as zoonosis in Colombia.

Comparative Pathology of Hepatitis A Virus and Hepatitis E Virus Infection.

Science.gov (United States)

Cullen, John M; Lemon, Stanley M

2018-04-30

Hepatitis A virus (HAV) and hepatitis E virus (HEV) cause acute, self-limiting hepatic infections that are usually spread by the fecal-oral route in humans. Naturally occurring and experimental infections are possible in a variety of nonhuman primates and, in the case of HEV, a number of other species. Many advances in understanding the pathogenesis of these viruses have come from studies in experimental animals. In general, animals infected with these viruses recapitulate the histologic lesions seen in infected humans, but typically with less severe clinical and histopathological manifestations. This review describes the histopathologic changes associated with HAV and HEV infection in humans and experimental animals. Copyright © 2018 Cold Spring Harbor Laboratory Press; all rights reserved.

[Zika virus infection during pregnancy].

Science.gov (United States)

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

2016-05-01

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. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Computer virus information update CIAC-2301

Energy Technology Data Exchange (ETDEWEB)

Orvis, W.J.

1994-01-15

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.

Human immunodeficiency virus and hepatitus B virus co-infection ...

African Journals Online (AJOL)

Human immunodeficiency virus and hepatitus B virus co-infection amog patients in Kano Nigeria. EE Nwokedi, MA Emokpae, AI Dutse. Abstract. No Abstract. Nigerian Journal of Medicine Vol. 15(3) July-September 2006: 227-229. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD ...

Vaccination with Recombinant Parainfluenza Virus 5 Expressing Neuraminidase Protects against Homologous and Heterologous Influenza Virus Challenge.

Science.gov (United States)

Mooney, Alaina J; Gabbard, Jon D; Li, Zhuo; Dlugolenski, Daniel A; Johnson, Scott K; Tripp, Ralph A; He, Biao; Tompkins, S Mark

2017-12-01

Seasonal human influenza virus continues to cause morbidity and mortality annually, and highly pathogenic avian influenza (HPAI) viruses along with other emerging influenza viruses continue to pose pandemic threats. Vaccination is considered the most effective measure for controlling influenza; however, current strategies rely on a precise vaccine match with currently circulating virus strains for efficacy, requiring constant surveillance and regular development of matched vaccines. Current vaccines focus on eliciting specific antibody responses against the hemagglutinin (HA) surface glycoprotein; however, the diversity of HAs across species and antigenic drift of circulating strains enable the evasion of virus-inhibiting antibody responses, resulting in vaccine failure. The neuraminidase (NA) surface glycoprotein, while diverse, has a conserved enzymatic site and presents an appealing target for priming broadly effective antibody responses. Here we show that vaccination with parainfluenza virus 5 (PIV5), a promising live viral vector expressing NA from avian (H5N1) or pandemic (H1N1) influenza virus, elicited NA-specific antibody and T cell responses, which conferred protection against homologous and heterologous influenza virus challenges. Vaccination with PIV5-N1 NA provided cross-protection against challenge with a heterosubtypic (H3N2) virus. Experiments using antibody transfer indicate that antibodies to NA have an important role in protection. These findings indicate that PIV5 expressing NA may be effective as a broadly protective vaccine against seasonal influenza and emerging pandemic threats. IMPORTANCE Seasonal influenza viruses cause considerable morbidity and mortality annually, while emerging viruses pose potential pandemic threats. Currently licensed influenza virus vaccines rely on the antigenic match of hemagglutinin (HA) for vaccine strain selection, and most vaccines rely on HA inhibition titers to determine efficacy, despite the growing

Influenza A virus targets a cGAS-independent STING pathway that controls enveloped RNA viruses.

Science.gov (United States)

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; Hornung, Veit; Lebbink, Robert Jan; Duch, Mogens; Fitzgerald, Katherine A; Bahrami, Shervin; Mikkelsen, Jakob Giehm; Hartmann, Rune; Paludan, Søren R

2016-02-19

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 conserved hemagglutinin fusion peptide (FP). Interestingly, FP antagonizes interferon production induced by membrane fusion or IAV but not by cGAMP or DNA. Similar to the enveloped RNA viruses, membrane fusion stimulates interferon production in a STING-dependent but cGAS-independent manner. Abolishment of this pathway led to reduced interferon production and impaired control of enveloped RNA viruses. Thus, enveloped RNA viruses stimulate a cGAS-independent STING pathway, which is targeted by IAV.

Enhanced light microscopy visualization of virus particles from Zika virus to filamentous ebolaviruses.

Directory of Open Access Journals (Sweden)

George G Daaboul

Full Text Available Light microscopy is a powerful tool in the detection and analysis of parasites, fungi, and prokaryotes, but has been challenging to use for the detection of individual virus particles. Unlabeled virus particles are too small to be visualized using standard visible light microscopy. Characterization of virus particles is typically performed using higher resolution approaches such as electron microscopy or atomic force microscopy. These approaches require purification of virions away from their normal millieu, requiring significant levels of expertise, and can only enumerate small numbers of particles per field of view. Here, we utilize a visible light imaging approach called Single Particle Interferometric Reflectance Imaging Sensor (SP-IRIS that allows automated counting and sizing of thousands of individual virions. Virions are captured directly from complex solutions onto a silicon chip and then detected using a reflectance interference imaging modality. We show that the use of different imaging wavelengths allows the visualization of a multitude of virus particles. Using Violet/UV illumination, the SP-IRIS technique is able to detect individual flavivirus particles (~40 nm, while green light illumination is capable of identifying and discriminating between vesicular stomatitis virus and vaccinia virus (~360 nm. Strikingly, the technology allows the clear identification of filamentous infectious ebolavirus particles and virus-like particles. The ability to differentiate and quantify unlabeled virus particles extends the usefulness of traditional light microscopy and can be embodied in a straightforward benchtop approach allowing widespread applications ranging from rapid detection in biological fluids to analysis of virus-like particles for vaccine development and production.

Cowpea viruses: Effect of single and mixed infections on symptomatology and virus concentration

Directory of Open Access Journals (Sweden)

Nsa Imade Y

2007-09-01

Full Text Available Abstract Natural multiple viral infections of cultivated cowpeas have been reported in Nigeria. In this study, three Nigerian commercial cowpea cultivars ("Olo 11", "Oloyin" and "White" and two lines from the IITA (IT86D- 719 and TVU 76 were mechanically inoculated with Cowpea aphid-borne mosaic virus (CABMV, Bean southern mosaic virus (SBMV and Cowpea mottle virus (CMeV singly, as well as in all possible combinations at 10, 20 and 30 days after planting (DAP. Samples of leaves or stems were collected at 10, 20 and 30 days after inoculation (DAI and analyzed for relative virus concentration by Enzyme-Linked Immunosrbent Assay. All the cultivars and lines {CVS/L} were susceptible to the viruses but the commercial CVS showed more severe symptoms and had relatively higher viral concentration. In single virus infections, CABMV which induced the most severe symptoms had absorbance values (at 405 nm of 0.11 to 0.46 while SBMV and CMeV which induced moderate symptoms had virus titre of 0.74 to 1.99 and 0.11 to 0.90 respectively. Plants inoculated 10 DAP had significantly higher virus concentration than those inoculated 30 DAP. In mixed infections involving CABMV (10 DAP apical necrosis and death were observed in commercial cultivars "Olo 11" and "White". Enhancement of CMeV titers were observed in plants infected with CMeV + CABMV. Multiple viral infections of cowpeas may result in complete yield loss, hence, the availability of seeds of cultivars with a high level of multiple virus resistance is recommended as a means of control.

Genome Sequence of Bivens Arm Virus, a Tibrovirus Belonging to the Species Tibrogargan virus (Mononegavirales: Rhabdoviridae).

Science.gov (United States)

Lauck, Michael; Yú, Shu Qìng; Caì, Yíngyún; Hensley, Lisa E; Chiu, Charles Y; O'Connor, David H; Kuhn, Jens H

2015-03-19

The new rhabdoviral genus Tibrovirus currently has two members, Coastal Plains virus and Tibrogargan virus. Here, we report the coding-complete genome sequence of a putative member of this genus, Bivens Arm virus. A genomic comparison reveals Bivens Arm virus to be closely related to, but distinct from, Tibrogargan virus. Copyright © 2015 Lauck et al.

Replication and clearance of respiratory syncytial virus - Apoptosis is an important pathway of virus clearance after experimental infection with bovine respiratory syncytial virus

DEFF Research Database (Denmark)

Viuff, B.; Tjørnehøj, Kirsten; Larsen, Lars Erik

2002-01-01

and clearance in a natural target animal. Replication of BRSV was demonstrated in the luminal part of the respiratory epithelial cells and replication in the upper respiratory tract preceded the replication in the lower respiratory tract. Virus excreted to the lumen of the respiratory tract was cleared...... and the infections with human respiratory syncytial. virus and BRSV have similar clinical, pathological, and epidemiological characteristics. In this study we used experimental BRSV infection in calves as a model of respiratory syncytial virus infection to demonstrate important aspects of viral replication......Human respiratory syncytial virus is an important cause of severe respiratory disease in young children, the elderly, and in immunocompromised adults. Similarly, bovine respiratory syncytial virus (BRSV) is causing severe, sometimes fatal, respiratory disease in calves. Both viruses are pneumovirus...

Temporal Analysis of Andes Virus and Sin Nombre Virus Infections of Syrian Hamsters

Science.gov (United States)

2007-05-01

Microbiology . All Rights Reserved. Temporal Analysis of Andes Virus and Sin Nombre Virus Infections of Syrian Hamsters Victoria Wahl-Jensen,1 Jennifer...Ye, C., J. Prescott , R. Nofchissey, D. Goade, and B. Hjelle. 2004. Neutralizing antibodies and Sin Nombre virus RNA after recovery from hantavirus

Monitoring virus entry into living cells using DiD-labeled dengue virus particles

NARCIS (Netherlands)

Ayala Nunez, Vanesa; Wilschut, Jan; Smit, Jolanda M.

2011-01-01

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

Neutralizing antibodies against flaviviruses, Babanki virus, and Rift Valley fever virus in Ugandan bats.

Science.gov (United States)

Kading, Rebekah C; Kityo, Robert M; Mossel, Eric C; Borland, Erin M; Nakayiki, Teddie; Nalikka, Betty; Nyakarahuka, Luke; Ledermann, Jeremy P; Panella, Nicholas A; Gilbert, Amy T; Crabtree, Mary B; Peterhans, Julian Kerbis; Towner, Jonathan S; Amman, Brian R; Sealy, Tara K; Nichol, Stuart T; Powers, Ann M; Lutwama, Julius J; Miller, Barry R

2018-01-01

Introduction: A number of arboviruses have previously been isolated from naturally-infected East African bats, however the role of bats in arbovirus maintenance is poorly understood. The aim of this study was to investigate the exposure history of Ugandan bats to a panel of arboviruses. Materials and methods: Insectivorous and fruit bats were captured from multiple locations throughout Uganda during 2009 and 2011-2013. All serum samples were tested for neutralizing antibodies against West Nile virus (WNV), yellow fever virus (YFV), dengue 2 virus (DENV-2), Zika virus (ZIKV), Babanki virus (BBKV), and Rift Valley fever virus (RVFV) by plaque reduction neutralization test (PRNT). Sera from up to 626 bats were screened for antibodies against each virus. Results and Discussion:  Key findings include the presence of neutralizing antibodies against RVFV in 5/52 (9.6%) of little epauletted fruit bats ( Epomophorus labiatus ) captured from Kawuku and 3/54 (5.6%) Egyptian rousette bats from Kasokero cave. Antibodies reactive to flaviviruses were widespread across bat taxa and sampling locations. Conclusion: The data presented demonstrate the widespread exposure of bats in Uganda to arboviruses, and highlight particular virus-bat associations that warrant further investigation.

Seasonal Dynamics of Haptophytes and dsDNA Algal Viruses Suggest Complex Virus-Host Relationship.

Science.gov (United States)

Johannessen, Torill Vik; Larsen, Aud; Bratbak, Gunnar; Pagarete, António; Edvardsen, Bente; Egge, Elianne D; Sandaa, Ruth-Anne

2017-04-20

Viruses influence the ecology and diversity of phytoplankton in the ocean. Most studies of phytoplankton host-virus interactions have focused on bloom-forming species like Emiliania huxleyi or Phaeocystis spp. The role of viruses infecting phytoplankton that do not form conspicuous blooms have received less attention. Here we explore the dynamics of phytoplankton and algal viruses over several sequential seasons, with a focus on the ubiquitous and diverse phytoplankton division Haptophyta, and their double-stranded DNA viruses, potentially with the capacity to infect the haptophytes. Viral and phytoplankton abundance and diversity showed recurrent seasonal changes, mainly explained by hydrographic conditions. By 454 tag-sequencing we revealed 93 unique haptophyte operational taxonomic units (OTUs), with seasonal changes in abundance. Sixty-one unique viral OTUs, representing Megaviridae and Phycodnaviridae , showed only distant relationship with currently isolated algal viruses. Haptophyte and virus community composition and diversity varied substantially throughout the year, but in an uncoordinated manner. A minority of the viral OTUs were highly abundant at specific time-points, indicating a boom-bust relationship with their host. Most of the viral OTUs were very persistent, which may represent viruses that coexist with their hosts, or able to exploit several host species.

Reference gene selection for quantitative real-time PCR analysis in virus infected cells: SARS corona virus, Yellow fever virus, Human Herpesvirus-6, Camelpox virus and Cytomegalovirus infections

Directory of Open Access Journals (Sweden)

Müller Marcel A

2005-02-01

Full Text Available Abstract Ten potential reference genes were compared for their use in experiments investigating cellular mRNA expression of virus infected cells. Human cell lines were infected with Cytomegalovirus, Human Herpesvirus-6, Camelpox virus, SARS coronavirus or Yellow fever virus. The expression levels of these genes and the viral replication were determined by real-time PCR. Genes were ranked by the BestKeeper tool, the GeNorm tool and by criteria we reported previously. Ranking lists of the genes tested were tool dependent. However, over all, β-actin is an unsuitable as reference gene, whereas TATA-Box binding protein and peptidyl-prolyl-isomerase A are stable reference genes for expression studies in virus infected cells.

Filovirus pathogenesis and immune evasion: insights from Ebola virus and Marburg virus

Energy Technology Data Exchange (ETDEWEB)

Messaoudi, Ilhem; Amarasinghe, Gaya K.; Basler, Christopher F.

2015-10-06

Ebola viruses and Marburg viruses, members of the filovirus family, are zoonotic pathogens that cause severe disease in people, as highlighted by the latest Ebola virus epidemic in West Africa. Filovirus disease is characterized by uncontrolled virus replication and the activation of host responses that contribute to pathogenesis. Underlying these phenomena is the potent suppression of host innate antiviral responses, particularly the type I interferon response, by viral proteins, which allows high levels of viral replication. In this Review, we describe the mechanisms used by filoviruses to block host innate immunity and discuss the links between immune evasion and filovirus pathogenesis.

PREFACE The physics of virus assembly The physics of virus assembly

Science.gov (United States)

Stockley, Peter G.; Twarock, Reidun

2010-12-01

Viruses are pathogens in every kingdom of life and are major causes of human disease and suffering. They are known to encompass a size range that overlaps with that of the smallest bacterial cells, and the largest viruses now seem to be hosts of their own viral pathogens. Recent genomic sequencing efforts show that many organisms have genes that are likely to be descended in evolution from viral progenitors. Even more astonishingly, analysis of the world's oceans has shown that some of the simplest viruses, the tailed dsDNA phages, are the most common biological entities on the planet, with estimates of their numbers ranging up to 1031, with ~ 1021 infection events every second, leading to a turnover of around 20% of the biomass in the sea every few days. These cycles of infection and lysis of oceanic bacteria and algae provide the nutrients for the smallest organisms lying at the bottom of the food chain. Without viruses, therefore, life on Earth would probably not be sustainable. These are remarkable facts for systems that are non-living in the strict sense, and are composed of simple materials—nucleic acids, proteins and lipids. Many viruses consist of little more than a protective protein coat surrounding their genomic nucleic acids, which can be either DNA or RNA. Their simplicity leads to highly symmetrical structures with protein containers based on helical or icosahedral lattices. Many simple viruses self-assemble rapidly and with great fidelity, and many groups are busy trying to exploit these properties to make virus-like particles for a wide range of applications, including targeted drug-delivery, medical imaging and even novel materials. This issue of Physical Biology contains a series of papers describing some of the latest experimental and theoretical research on viruses, their structures and assembly, as well as their regulated disassembly during infection. These range from a dissection of the in vivo assembly mechanism of a filamentous virus

Coping with Computer Viruses: General Discussion and Review of Symantec Anti-Virus for the Macintosh.

Science.gov (United States)

Primich, Tracy

1992-01-01

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)

Presence and Distribution of Oilseed Pumpkin Viruses and Molecular Detection of Zucchini Yellow Mosaic Virus

Directory of Open Access Journals (Sweden)

Ana Vučurović

2009-01-01

Full Text Available Over the past decade, intensive spread of virus infections of oilseed pumpkin has resulted in significant economic losses in pumpkin crop production, which is currently expanding in our country. In 2007 and 2008, a survey for the presence and distribution of oilseed pumpkin viruses was carried out in order to identify viruses responsible for epidemics and incidences of very destructive symptoms on cucurbit leaves and fruits. Monitoring andcollecting samples of oil pumpkin, as well as other species such as winter and butternut squash and buffalo and bottle gourd with viral infection symptoms, was conducted in several localities of Vojvodina Province. The collected plant samples were tested by DAS-ELISA using polyclonal antisera specific for the detection of six most economically harmful pumpkin viruses: Cucumber mosaic virus (CMV, Zucchini yellow mosaic virus (ZYMV, Watermelon mosaic virus (WMW, Squash mosaic virus (SqMV, Papaya ringspot virus (PRSV and Tobaccoringspot virus (TRSV that are included in A1 quarantine list of harmful organisms in Serbia.Identification of viruses in the collected samples indicated the presence of three viruses, ZYMV, WMV and CMV, in individual and mixed infections. Frequency of the identified viruses varied depending on locality and year of investigations. In 2007, WMV was the most frequent virus (94.2%, while ZYMV was prevalent (98.04% in 2008. High frequency of ZYMV determined in both years of investigation indicated the need for its rapid and reliable molecular detection. During this investigation, a protocol for ZYMVdetection was developed and optimized using specific primers CPfwd/Cprev and commercial kits for total RNA extraction, as well as for RT-PCR. In RT-PCR reaction using these primers, a DNA fragment of approximately 1100 bp, which included coat protein gene, was amplified in the samples of infected pumkin leaves. Although serological methods are still useful for large-scale testing of a great number of

Archaeal virus-host interactions

NARCIS (Netherlands)

Quax, T.E.F.

2013-01-01

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

Prevalence of hepatitis A virus, hepatitis B virus, hepatitis C virus, hepatitis D virus and hepatitis E virus as causes of acute viral hepatitis in North India: a hospital based study.

Science.gov (United States)

Jain, P; Prakash, S; Gupta, S; Singh, K P; Shrivastava, S; Singh, D D; Singh, J; Jain, A

2013-01-01

Acute viral hepatitis (AVH) is a major public health problem and is an important cause of morbidity and mortality. The aim of the present study is to determine the prevalence of hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV) and hepatitis E virus (HEV) as causes of AVH in a tertiary care hospital of North India. Blood samples and clinical information was collected from cases of AVH referred to the Grade I viral diagnostic laboratory over a 1-year period. Samples were tested for hepatitis B surface antigen, anti-HCV total antibodies, anti-HAV immunoglobulin M (IgM) and anti-HEV IgM by the enzyme-linked immunosorbent assay. PCR for nucleic acid detection of HBV and HCV was also carried out. Those positive for HBV infection were tested for anti-HDV antibodies. Fisher's exact test was used and a P hepatitis cases, 62 (23.22%) patients presented as acute hepatic failure. HAV (26.96%) was identified as the most common cause of acute hepatitis followed by HEV (17.97%), HBV (16.10%) and HCV (11.98%). Co-infections with more than one virus were present in 34 cases; HAV-HEV co-infection being the most common. HEV was the most important cause of acute hepatic failure followed by co-infection with HAV and HEV. An indication towards epidemiological shift of HAV infection from children to adults with a rise in HAV prevalence was seen. To the best of our knowledge, this is the first report indicating epidemiological shift of HAV in Uttar Pradesh.

Epstein-Barr virus, human papillomavirus and mouse mammary tumour virus as multiple viruses in breast cancer.

Science.gov (United States)

Glenn, Wendy K; Heng, Benjamin; Delprado, Warick; Iacopetta, Barry; Whitaker, Noel J; Lawson, James S

2012-01-01

The purpose of this investigation is to determine if Epstein Barr virus (EBV), high risk human papillomavirus (HPV), and mouse mammary tumour viruses (MMTV) co-exist in some breast cancers. All the specimens were from women residing in Australia. For investigations based on standard PCR, we used fresh frozen DNA extracts from 50 unselected invasive breast cancers. For normal breast specimens, we used DNA extracts from epithelial cells from milk donated by 40 lactating women. For investigations based on in situ PCR we used 27 unselected archival formalin fixed breast cancer specimens and 18 unselected archival formalin fixed normal breast specimens from women who had breast reduction surgery. Thirteen of these fixed breast cancer specimens were ductal carcinoma in situ (dcis) and 14 were predominantly invasive ductal carcinomas (idc). EBV sequences were identified in 68%, high risk HPV sequences in 50%, and MMTV sequences in 78% of DNA extracted from 50 invasive breast cancer specimens. These same viruses were identified in selected normal and breast cancer specimens by in situ PCR. Sequences from more than one viral type were identified in 72% of the same breast cancer specimens. Normal controls showed these viruses were also present in epithelial cells in human milk - EBV (35%), HPV, 20%) and MMTV (32%) of 40 milk samples from normal lactating women, with multiple viruses being identified in 13% of the same milk samples. We conclude that (i) EBV, HPV and MMTV gene sequences are present and co-exist in many human breast cancers, (ii) the presence of these viruses in breast cancer is associated with young age of diagnosis and possibly an increased grade of breast cancer.

Inhibition of Interferon Induction and Action by the Nairovirus Nairobi Sheep Disease Virus/Ganjam Virus

OpenAIRE

Holzer, Barbara; Bakshi, Siddharth; Bridgen, Anne; Baron, Michael D.

2011-01-01

The Nairoviruses are an important group of tick-borne viruses that includes pathogens of man (Crimean Congo hemorrhagic fever virus) and livestock animals (Dugbe virus, Nairobi sheep disease virus (NSDV)). NSDV is found in large parts of East Africa and the Indian subcontinent (where it is known as Ganjam virus). We have investigated the ability of NSDV to antagonise the induction and actions of interferon. Both pathogenic and apathogenic isolates could actively inhibit the induction of type ...

Characterization of Ebola Virus Entry by Using Pseudotyped Viruses: Identification of Receptor-Deficient Cell Lines

OpenAIRE

Wool-Lewis, Rouven J.; Bates, Paul

1998-01-01

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 ...

Das Epstein-Barr-Virus ( = Epstein-Barr virus)

OpenAIRE

Niller, H. H.; Wolf, Hans J.

1993-01-01

Epstein-Barr virus is an ubiquitous humanpathogenic herpesvirus. It has been identified as the etiologic agent of infectious mononucleosis. In addition it is associated with the cancers nasopharyngeal carcinoma and Burkitt's lymphoma. Like other herpesviruses it infects cells in a lytic way or it persists in a latent state. Classically, the serologic diagnosis of Epstein-Barr virus infections is done by the agglutination of sheep erythrocytes according to Paul and Bunnell as a rapid testing m...

[Viruses and civilization].

Science.gov (United States)

Chastel, C

1999-01-01

A few million years ago, when primates moved from the east African forest to the savannah, they were already infected with endogenous viruses and occultly transmitted them to the prime Homo species. However it was much later with the building of the first large cities in Mesopotamia that interhuman viral transmission began in earnest. Spreading was further enhanced with the organization of the Egyptian, Greek, Roman, and Arab empires around the Mediterranean. Discovery of the New World in 1492 led to an unprecedented clash of civilizations and the destruction of pre-Columbian Indian civilizations. It also led to a rapid spread of viruses across the Atlantic Ocean with the emergence of yellow fever and appearance of smallpox and measles throughout the world. However the greatest opportunities for worldwide viral development have been created by our present, modern civilization. This fact is illustrated by epidemic outbreaks of human immunodeficiency virus, Venezuela hemorrhagic fever, Rift valley fever virus, and monkey pox virus. Close analysis underscores the major role of human intervention in producing these events.

Comparative analysis of rabbit hemorrhagic disease virus (RHDV) and new RHDV2 virus antigenicity, using specific virus-like particles

OpenAIRE

Bárcena, Juan; Guerra, Beatriz; Angulo, Iván; González, Julia; Valcárcel, Félix; Mata, Carlos P.; Castón, José R.; Blanco, Esther; Alejo, Alí

2015-01-01

International audience; In 2010 a new Lagovirus related to rabbit haemorrhagic disease virus (RHDV) emerged in France and has since rapidly spread throughout domestic and wild rabbit populations of several European countries. The new virus, termed RHDV2, exhibits distinctive genetic, antigenic and pathogenic features. Notably, RHDV2 kills rabbits previously vaccinated with RHDV vaccines. Here we report for the first time the generation and characterization of RHDV2-specific virus-like particl...

RECOVIR Software for Identifying Viruses

Science.gov (United States)

Chakravarty, Sugoto; Fox, George E.; Zhu, Dianhui

2013-01-01

Most single-stranded RNA (ssRNA) viruses mutate rapidly to generate a large number of strains with highly divergent capsid sequences. Determining the capsid residues or nucleotides that uniquely characterize these strains is critical in understanding the strain diversity of these viruses. RECOVIR (an acronym for "recognize viruses") software predicts the strains of some ssRNA viruses from their limited sequence data. Novel phylogenetic-tree-based databases of protein or nucleic acid residues that uniquely characterize these virus strains are created. Strains of input virus sequences (partial or complete) are predicted through residue-wise comparisons with the databases. RECOVIR uses unique characterizing residues to identify automatically strains of partial or complete capsid sequences of picorna and caliciviruses, two of the most highly diverse ssRNA virus families. Partition-wise comparisons of the database residues with the corresponding residues of more than 300 complete and partial sequences of these viruses resulted in correct strain identification for all of these sequences. This study shows the feasibility of creating databases of hitherto unknown residues uniquely characterizing the capsid sequences of two of the most highly divergent ssRNA virus families. These databases enable automated strain identification from partial or complete capsid sequences of these human and animal pathogens.

Hepatitis virus panel

Science.gov (United States)

... page: //medlineplus.gov/ency/article/003558.htm Hepatitis virus panel To use the sharing features on this page, please enable JavaScript. The hepatitis virus panel is a series of blood tests used ...

Polyomavirus specific cellular immunity: from BK-virus-specific cellular immunity to BK-virus-associated nephropathy ?

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manon edekeyser

2015-06-01

Full Text Available In renal transplantation, BK-virus-associated nephropathy has emerged as a major complication, with a prevalence of 5–10% and graft loss in >50% of cases. BK-virus is a member of the Polyomavirus family and rarely induces apparent clinical disease in the general population. However, replication of polyomaviruses, associated with significant organ disease, is observed in patients with acquired immunosuppression, which suggests a critical role for virus-specific cellular immunity to control virus replication and prevent chronic disease. Monitoring of specific immunity combined with viral load could be used to individually assess the risk of viral reactivation and virus control. We review the current knowledge on BK-virus specific cellular immunity and, more specifically, in immunocompromised patients. In the future, immune-based therapies could allow us to treat and prevent BK-virus-associated nephropathy.

Outbreaks of influenza A virus in farmed mink (Neovison vison) in Denmark: molecular characterization of the viruses

DEFF Research Database (Denmark)

Larsen, Lars Erik; Breum, Solvej Østergaard; Trebbien, Ramona

2012-01-01

that the virus was a human/swine reassortant, with the H and N gene most related to human H3N2 viruses circulating in 2005. The remaining 6 genes were most closely related to H1N2 influenza viruses circulating in Danish swine. This virus had not previously been described in swine, mink or humans. PCRs assays...... specifically targeting the new reassortant were developed and used to screen influenza positive samples from humans and swine in Denmark with negative results. Thus, there was no evidence that this virus had spread to humans or was circulating in Danish pigs. In 2010 and 2011, influenza virus was again...... diagnosed in diseased mink in a few farms. The genetic typing showed that the virus was similar to the pandemic H1N1 virus circulating in humans and swine. The H3N2 virus was not detected in 2010 and 2011. Taken together, these findings indicate that mink is highly susceptible for influenza A virus of human...

Diversity of viruses in Ixodes ricinus, and characterization of a neurotropic strain of Eyach virus

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S. Moutailler

2016-05-01

Full Text Available Ticks transmit more pathogens—including bacteria, parasites and viruses—than any other arthropod vector. Although the epidemiological status of many tick-borne bacteria is very well characterized, tick-borne viruses are still relatively under-studied. Recently, several novel tick-borne viruses have been isolated from human febrile illnesses following tick bites, indicating the existence of other potential new and unknown tick-borne viruses. We used high-throughput sequencing to analyse the virome of Ixodes ricinus, the main vector of tick-borne pathogens in Europe. The majority of collected viral sequences were assigned to two potentially novel Nairovirus and Phlebovirus viruses, with prevalence rates ranging from 3.95% to 23.88% in adults and estimated to be between 0.14% and 72.16% in nymphs. These viruses could not be isolated from the brains of inoculated immunocompromised mice, perhaps indicating that they are unable to infect vertebrates. Within the I. ricinus virome, we also identified contigs with >90% identity to the known Eyach virus. Initially isolated in the 1980s, this virus was indirectly associated with human disease, but had never been extensively studied. Eyach virus prevalence varied between 0.07% and 5.26% in ticks from the French Ardennes and Alsace regions. Eyach virus was successfully isolated following intracerebral inoculation of immunocompromised mice with Eyach virus-positive tick extracts. This virus was also able to multiply and persist in the blood of immunocompetent mice inoculated by intraperitoneal injection, and caused brain infections in three of nine juveniles, without any obvious deleterious effects.

Analysis of proteins of mouse sarcoma pseudotype viruses: type-specific radioimmunoassays for ecotropic virus p30's

International Nuclear Information System (INIS)

Kennel, S.J.; Tennant, R.W.

1979-01-01

Murine sarcoma virus pseudotypes were prepared by infection of nonproducer cells (A1-2), which were transformed by the Gazdar strain of mouse sarcoma virus, with Gross (N-tropic), WN1802B (B-tropic), or Moloney (NB-tropic) viruses. The respective host range pseudotype sarcoma viruses were defined by the tritration characteristics on cells with the appropriate Fv-1 genotype. Proteins from virus progeny were analyzed by sodium dodecyl sulfate--polyacrylamide gel electrophoresis. Bands present in both the 65,000- and the 10,000- to 20,000-molecular-weight regions of the gel distinguished the pseudotype viruses from their respective helpers. Furthermore, two protein bands were noted in the p30 region of murine sarcoma virus (Gross), one corresponding to Gross virus p30, and another of slightly slower mobility. However, since the mobility of the putative sarcoma p30 is nearly indentical to that of WN1802B, its presence could not be established by sodium dodecyl sulfate--polyacrylamide gel electrophoresis. Type-specific radioimmunossays for Gross virus p30 and for WN1802B p30 were applied for analysis of pseudotype preparations, and among several ecotropic viruses tested, only the homologous virus scored in the respective assay. By use of these assays, pseudotype viruses were found to contain only 8 to 48% helper-specific p30's; the remainder is presumably derived from the sarcoma virus

Characteristic of pandemic virus

Indian Academy of Sciences (India)

First page Back Continue Last page Graphics. Characteristic of pandemic virus. The virus was highly transmissible. Risk of hospitalization was 2X and risk of death was about 11X more in comparison to seasonal influenza. Virus continues to be susceptible to Osaltamivir, the only drug available. Vaccines are available but ...

Avian influenza viruses in humans.

Science.gov (United States)

Malik Peiris, J S

2009-04-01

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 have a predilection to cause conjunctivitis and influenza-like illness (ILI), although HPAI H7N7 virus has also caused fatal respiratory disease. Low pathogenic H9N2 viruses have caused mild ILI and its occurrence may be under-recognised for this reason. In contrast, contemporary HPAI H5N1 viruses are exceptional in their virulence for humans and differ from human seasonal influenza viruses in their pathogenesis. Patients have a primary viral pneumonia progressing to acute respiratory distress syndrome (ARDS) and multiple organ dysfunction syndrome. Over 380 human cases have been confirmed to date, with an overall case fatality of 63%. The zoonotic transmission of avian influenza is a rare occurrence, butthe greater public health concern is the adaptation of such viruses to efficient human transmission, which could lead to a pandemic. A better understanding of the ecology of avian influenza viruses and the biological determinants of transmissibility and pathogenicity in humans is important for pandemic preparedness.

Zika virus infection: a public health emergency!

OpenAIRE

Qureshi, Muhammad Salman Haider; Qureshi, Bakhtawar Wajeeha; Khan, Ramsha

2017-01-01

Zika virus belongs to the family of Flaviviridae. The Flaviviridae family also includes other human pathogens like West Nile virus (WNV), Yellow fever virus (YFV), mosquito transmitted Dengue virus (DENV), Tick borne encephalitic virus (TBEV) and Japanese encephalitis virus (JEV). Zika virus is a mosquito-borne disease and is transmitted by Aedes aegypti mosquito.

Human Parainfluenza Viruses

Science.gov (United States)

... Search Form Controls Cancel Submit Search The CDC Human Parainfluenza Viruses (HPIVs) Note: Javascript is disabled or ... CDC.gov . Recommend on Facebook Tweet Share Compartir Human parainfluenza viruses (HPIVs) commonly cause respiratory illnesses in ...

Respiratory Syncytial Virus

Science.gov (United States)

... with facebook share with twitter share with linkedin Respiratory Syncytial Virus (RSV) Credit: CDC This is the ... the United States. Why Is the Study of Respiratory Syncytial Virus (RSV) a Priority for NIAID? In ...

Antiviral Activity of Sukomycin Against Potato Virus Y And Tomato Mosaic Virus

Directory of Open Access Journals (Sweden)

Nikolay Petrov

2016-12-01

Full Text Available Potato virus Y (PVY and Tomato mosaic virus (ToMV are one of the most important plant viruses that strongly influence the quality and quantity of vegetable production and cause substantial losses to farmers. The most convetional and common method of pest and disease control is trough the use of pesticides. Unfortunately, most of them are synthetic compounds without antiviral activities and possess inherent toxicities that endanger the health of the farm operators, consumers and the environment. In order to carry out a control of viral infections in plants and to reduce the loss of production it is necessary the search for alternative and environmentally friendly methods for control. Sukomycin is a complex of substances with antimicrobial and antiviral activities produced from Streptomyces hygroscopicus isolated from soil. This natural complex reduces significantly symptoms and DAS-ELISA values of Potato virus Y and Tomato mosaic virus in tobacco plants.

Prevention of Hepatitis B Virus and Hepatitis C Virus Transmission ...

African Journals Online (AJOL)

Introduction: Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections in hemodialysis (HD) patients are associated with adverse outcomes, especially after kidney transplantation. Review: In the HD setting, cross-contamination to patients via environmental surfaces, supplies, equipment, multiple-dose medication vials ...

A fusion-inhibiting peptide against Rift Valley fever virus inhibits multiple, diverse viruses.

Directory of Open Access Journals (Sweden)

Jeffrey W Koehler

Full Text Available For enveloped viruses, fusion of the viral envelope with a cellular membrane is critical for a productive infection to occur. This fusion process is mediated by at least three classes of fusion proteins (Class I, II, and III based on the protein sequence and structure. For Rift Valley fever virus (RVFV, the glycoprotein Gc (Class II fusion protein mediates this fusion event following entry into the endocytic pathway, allowing the viral genome access to the cell cytoplasm. Here, we show that peptides analogous to the RVFV Gc stem region inhibited RVFV infectivity in cell culture by inhibiting the fusion process. Further, we show that infectivity can be inhibited for diverse, unrelated RNA viruses that have Class I (Ebola virus, Class II (Andes virus, or Class III (vesicular stomatitis virus fusion proteins using this single peptide. Our findings are consistent with an inhibition mechanism similar to that proposed for stem peptide fusion inhibitors of dengue virus in which the RVFV inhibitory peptide first binds to both the virion and cell membranes, allowing it to traffic with the virus into the endocytic pathway. Upon acidification and rearrangement of Gc, the peptide is then able to specifically bind to Gc and prevent fusion of the viral and endocytic membranes, thus inhibiting viral infection. These results could provide novel insights into conserved features among the three classes of viral fusion proteins and offer direction for the future development of broadly active fusion inhibitors.

Inactivated Recombinant Rabies Viruses Displaying Canine Distemper Virus Glycoproteins Induce Protective Immunity against Both Pathogens.

Science.gov (United States)

da Fontoura Budaszewski, Renata; Hudacek, Andrew; Sawatsky, Bevan; Krämer, Beate; Yin, Xiangping; Schnell, Matthias J; von Messling, Veronika

2017-04-15

The development of multivalent vaccines is an attractive methodology for the simultaneous prevention of several infectious diseases in vulnerable populations. Both canine distemper virus (CDV) and rabies virus (RABV) cause lethal disease in wild and domestic carnivores. While RABV vaccines are inactivated, the live-attenuated CDV vaccines retain residual virulence for highly susceptible wildlife species. In this study, we developed recombinant bivalent vaccine candidates based on recombinant vaccine strain rabies virus particles, which concurrently display the protective CDV and RABV glycoprotein antigens. The recombinant viruses replicated to near-wild-type titers, and the heterologous glycoproteins were efficiently expressed and incorporated in the viral particles. Immunization of ferrets with beta-propiolactone-inactivated recombinant virus particles elicited protective RABV antibody titers, and animals immunized with a combination of CDV attachment protein- and fusion protein-expressing recombinant viruses were protected from lethal CDV challenge. However, animals that were immunized with only a RABV expressing the attachment protein of CDV vaccine strain Onderstepoort succumbed to infection with a more recent wild-type strain, indicating that immune responses to the more conserved fusion protein contribute to protection against heterologous CDV strains. IMPORTANCE Rabies virus and canine distemper virus (CDV) cause high mortality rates and death in many carnivores. While rabies vaccines are inactivated and thus have an excellent safety profile and high stability, live-attenuated CDV vaccines can retain residual virulence in highly susceptible species. Here we generated recombinant inactivated rabies viruses that carry one of the CDV glycoproteins on their surface. Ferrets immunized twice with a mix of recombinant rabies viruses carrying the CDV fusion and attachment glycoproteins were protected from lethal CDV challenge, whereas all animals that received

Archaeal Viruses from High-Temperature Environments.

Science.gov (United States)

Munson-McGee, Jacob H; Snyder, Jamie C; Young, Mark J

2018-02-27

Archaeal viruses are some of the most enigmatic viruses known, due to the small number that have been characterized to date. The number of known archaeal viruses lags behind known bacteriophages by over an order of magnitude. Despite this, the high levels of genetic and morphological diversity that archaeal viruses display has attracted researchers for over 45 years. Extreme natural environments, such as acidic hot springs, are almost exclusively populated by Archaea and their viruses, making these attractive environments for the discovery and characterization of new viruses. The archaeal viruses from these environments have provided insights into archaeal biology, gene function, and viral evolution. This review focuses on advances from over four decades of archaeal virology, with a particular focus on archaeal viruses from high temperature environments, the existing challenges in understanding archaeal virus gene function, and approaches being taken to overcome these limitations.

Archaeal Viruses from High-Temperature Environments

Directory of Open Access Journals (Sweden)

Jacob H. Munson-McGee

2018-02-01

Full Text Available Archaeal viruses are some of the most enigmatic viruses known, due to the small number that have been characterized to date. The number of known archaeal viruses lags behind known bacteriophages by over an order of magnitude. Despite this, the high levels of genetic and morphological diversity that archaeal viruses display has attracted researchers for over 45 years. Extreme natural environments, such as acidic hot springs, are almost exclusively populated by Archaea and their viruses, making these attractive environments for the discovery and characterization of new viruses. The archaeal viruses from these environments have provided insights into archaeal biology, gene function, and viral evolution. This review focuses on advances from over four decades of archaeal virology, with a particular focus on archaeal viruses from high temperature environments, the existing challenges in understanding archaeal virus gene function, and approaches being taken to overcome these limitations.

A Foxtail mosaic virus Vector for Virus-Induced Gene Silencing in Maize1[OPEN

Science.gov (United States)

Mei, Yu; Kernodle, Bliss M.; Hill, John H.

2016-01-01

Plant viruses have been widely used as vectors for foreign gene expression and virus-induced gene silencing (VIGS). A limited number of viruses have been developed into viral vectors for the purposes of gene expression or VIGS in monocotyledonous plants, and among these, the tripartite viruses Brome mosaic virus and Cucumber mosaic virus have been shown to induce VIGS in maize (Zea mays). We describe here a new DNA-based VIGS system derived from Foxtail mosaic virus (FoMV), a monopartite virus that is able to establish systemic infection and silencing of endogenous maize genes homologous to gene fragments inserted into the FoMV genome. To demonstrate VIGS applications of this FoMV vector system, four genes, phytoene desaturase (functions in carotenoid biosynthesis), lesion mimic22 (encodes a key enzyme of the porphyrin pathway), iojap (functions in plastid development), and brown midrib3 (caffeic acid O-methyltransferase), were silenced and characterized in the sweet corn line Golden × Bantam. Furthermore, we demonstrate that the FoMV infectious clone establishes systemic infection in maize inbred lines, sorghum (Sorghum bicolor), and green foxtail (Setaria viridis), indicating the potential wide applications of this viral vector system for functional genomics studies in maize and other monocots. PMID:27208311

Avian influenza virus transmission to mammals.

Science.gov (United States)

Herfst, S; Imai, M; Kawaoka, Y; Fouchier, R A M

2014-01-01

Influenza A viruses cause yearly epidemics and occasional pandemics. In addition, zoonotic influenza A viruses sporadically infect humans and may cause severe respiratory disease and fatalities. Fortunately, most of these viruses do not have the ability to be efficiently spread among humans via aerosols or respiratory droplets (airborne transmission) and to subsequently cause a pandemic. However, adaptation of these zoonotic viruses to humans by mutation or reassortment with human influenza A viruses may result in airborne transmissible viruses with pandemic potential. Although our knowledge of factors that affect mammalian adaptation and transmissibility of influenza viruses is still limited, we are beginning to understand some of the biological traits that drive airborne transmission of influenza viruses among mammals. Increased understanding of the determinants and mechanisms of airborne transmission may aid in assessing the risks posed by avian influenza viruses to human health, and preparedness for such risks. This chapter summarizes recent discoveries on the genetic and phenotypic traits required for avian influenza viruses to become airborne transmissible between mammals.

Zika virus disease

Science.gov (United States)

... May 2015, the virus was discovered for the first time in Brazil. It has now spread to many territories, states, and countries in: Caribbean Islands Central America Mexico South America Pacific Islands Africa The virus ...

Isolation and characterization of a cDNA clone coding for a glutathione S-transferase class delta enzyme from the biting midge Culicoides variipennis sonorensis Wirth and Jones.

Science.gov (United States)

Abdallah, M A; Pollenz, R S; Droog, F N; Nunamaker, R A; Tabachnick, W J; Murphy, K E

2000-12-01

Culicoides variipennis sonorensis is the primary vector of bluetongue viruses in North America. Glutathione S-transferases (GSTs) are enzymes that catalyze nucleophilic substitutions, converting reactive lipophilic molecules into soluble conjugates. Increased GST activity is associated with development of insecticide resistance. Described here is the isolation of the first cDNA encoding a C. variipennis GST. The clone consists of 720 translated bases encoding a protein with a M(r) of approximately 24,800 composed of 219 amino acids. The deduced amino acid sequence is similar (64%-74%) to class Delta (previously named Theta) GSTs from the dipteran genera Musca, Drosophila, Lucilia and Anopheles. The cDNA was subcloned into pET-11b, expressed in Epicurian coli BL21 (DE3) and has a specific activity of approximately 28,000 units/mg for the substrate 1-chloro-2,4-dinitrobenzene.

A recombinant canine distemper virus expressing a modified rabies virus glycoprotein induces immune responses in mice.

Science.gov (United States)

Li, Zhili; Wang, Jigui; Yuan, Daoli; Wang, Shuang; Sun, Jiazeng; Yi, Bao; Hou, Qiang; Mao, Yaping; Liu, Weiquan

2015-06-01

Canine distemper virus (CDV) and rabies virus (RV) are two important pathogens of the dog. CDV, a member of the morbillivirus genus, has shown promise as an expression vector. The glycoprotein from RV is a main contributor to protective immunity and capable of eliciting the production of virus-neutralizing antibodies. In this study, we recovered an attenuated strain of canine distemper virus and constructed a recombinant virus, rCDV-RV-G, expressing a modified (R333Q) rabies virus glycoprotein (RV-G) of RV Flury strain LEP. RV-G expression by the recombinant viruses was confirmed. Furthermore, G was proved to be incorporated into the surface of CDV particles. While replication of the recombinant virus was slightly reduced compared with the parental CDV, it stably expressed the RV-G over ten serial passages. Inoculation of mice induced specific neutralizing antibodies against both RV-G and CDV. Therefore, the rCDV-RV-G has the potential as a vaccine that may be used to control rabies virus infection in dogs and other animals.

Identification and characterization of a virus-specific continuous B-cell epitope on the PrM/M protein of Japanese Encephalitis Virus: potential application in the detection of antibodies to distinguish Japanese Encephalitis Virus infection from West Nile Virus and Dengue Virus infections

OpenAIRE

Hua, Rong-Hong; Chen, Na-Sha; Qin, Cheng-Feng; Deng, Yong-Qiang; Ge, Jin-Ying; Wang, Xi-Jun; Qiao, Zu-Jian; Chen, Wei-Ye; Wen, Zhi-Yuan; Liu, Wen-Xin; Hu, Sen; Bu, Zhi-Gao

2010-01-01

Abstract Background Differential diagnose of Japanese encephalitis virus (JEV) infection from other flavivirus especially West Nile virus (WNV) and Dengue virus (DV) infection was greatly hindered for the serological cross-reactive. Virus specific epitopes could benefit for developing JEV specific antibodies detection methods. To identify the JEV specific epitopes, we fully mapped and characterized the continuous B-cell epitope of the PrM/M protein of JEV. Results To map the epitopes on the P...

Expression of varicella-zoster virus and herpes simplex virus in normal human trigeminal ganglia

International Nuclear Information System (INIS)

Vafai, A.; Wellish, M.; Devlin, M.; Gilden, D.H.; Murray, R.S.

1988-01-01

Lysates of radiolabeled explants from four human trigeminal ganglia were immunoprecipitated with antibodies to varicella-zoster virus (VZV) and to herpes simplex virus. Both herpes simplex virus- and VZV-specific proteins were detected in lysates of all four ganglia. Absence of reactivity in ganglion explants with monoclonal antibodies suggested that herpes simplex virus and VZV were not reactivated during the culture period. In situ hybridization studies demonstrated the presence of RNA transcripts from the VZV immediate early gene 63. This approach to the detection of herpes simplex virus and VZV expression in human ganglia should facilitate analysis of viral RNA and proteins in human sensory ganglia

Thermoactivation of viruses by microwaves

Energy Technology Data Exchange (ETDEWEB)

Mahnel, H.; von Brodorotti, H.S.

1981-01-01

Eight different viruses, suspended in drinking water, were examined for their ability to be inactivated by microwaves from a microwave oven. Up to a virus content of 10/sup 5/ TCID/sub 50//ml inactivation was successful within a few minutes of microwave treatment and occurred in parallel to the heat stability of the viruses. Evidence for direct effects of microwaves on viruses could not be detected. 7 of the viruses studied were inactivated rapidly when temperatures of 50 to 65/sup 0/C under microwave treatment were reached in the flowing water, while a bovine parvovirus was only inactivated by temperatures above 90/sup 0/C. The advantages of a thermal virus-decontamination of fluids and material by microwaves are discussed.

Autophagic machinery activated by dengue virus enhances virus replication

International Nuclear Information System (INIS)

Lee, Y.-R.; Lei, H.-Y.; Liu, M.-T.; Wang, J.-R.; Chen, S.-H.; Jiang-Shieh, Y.-F.; Lin, Y.-S.; Yeh, T.-M.; Liu, C.-C.; Liu, H.-S.

2008-01-01

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

Animal Models of Zika Virus

Science.gov (United States)

Bradley, Michael P; Nagamine, Claude M

2017-01-01

Zika virus has garnered great attention over the last several years, as outbreaks of the disease have emerged throughout the Western Hemisphere. Until quite recently Zika virus was considered a fairly benign virus, with limited clinical severity in both people and animals. The size and scope of the outbreak in the Western Hemisphere has allowed for the identification of severe clinical disease that is associated with Zika virus infection, most notably microcephaly among newborns, and an association with Guillian–Barré syndrome in adults. This recent association with severe clinical disease, of which further analysis strongly suggested causation by Zika virus, has resulted in a massive increase in the amount of both basic and applied research of this virus. Both small and large animal models are being used to uncover the pathogenesis of this emerging disease and to develop vaccine and therapeutic strategies. Here we review the animal-model–based Zika virus research that has been performed to date. PMID:28662753

78 FR 29755 - Human Immunodeficiency Virus Patient-Focused Drug Development and Human Immunodeficiency Virus...

Science.gov (United States)

2013-05-21

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2013-N-0473] Human Immunodeficiency Virus Patient-Focused Drug Development and Human Immunodeficiency Virus Cure... an opportunity for public comment on human immunodeficiency virus (HIV) Patient-Focused Drug...

Natural history and treatment of hepatitis B virus and hepatitis C virus coinfection

Directory of Open Access Journals (Sweden)

Keeffe Emmet B

2005-09-01

Full Text Available Abstract Hepatitis B virus (HBV and hepatitis C virus (HCV coinfection is not uncommon as a result of similar routes of infection. Patients who are coinfected represent a unique group with diverse serologic profiles. Combined chronic hepatitis B and C leads to more severe liver disease and an increased risk of hepatocellular carcinoma. Furthermore, coinfected patients represent a treatment challenge. No standard recommendations exist for treatment of viral hepatitis due to dual HBV/HCV infection, and therefore treatment must be individualized based on patient variables such as serologic and virologic profiles, patient's prior exposure to antiviral treatment, and the presence of other parenterally transmitted viruses such as hepatitis D virus and human immunodeficiency virus. The natural history and treatment of patients with HBV and HCV coinfection is reviewed.

Codon usage bias and the evolution of influenza A viruses. Codon Usage Biases of Influenza Virus

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Wong Emily HM

2010-08-01

Full Text Available Abstract Background The influenza A virus is an important infectious cause of morbidity and mortality in humans and was responsible for 3 pandemics in the 20th century. As the replication of the influenza virus is based on its host's machinery, codon usage of its viral genes might be subject to host selection pressures, especially after interspecies transmission. A better understanding of viral evolution and host adaptive responses might help control this disease. Results Relative Synonymous Codon Usage (RSCU values of the genes from segment 1 to segment 6 of avian and human influenza viruses, including pandemic H1N1, were studied via Correspondence Analysis (CA. The codon usage patterns of seasonal human influenza viruses were distinct among their subtypes and different from those of avian viruses. Newly isolated viruses could be added to the CA results, creating a tool to investigate the host origin and evolution of viral genes. It was found that the 1918 pandemic H1N1 virus contained genes with mammalian-like viral codon usage patterns, indicating that the introduction of this virus to humans was not through in toto transfer of an avian influenza virus. Many human viral genes had directional changes in codon usage over time of viral isolation, indicating the effect of host selection pressures. These changes reduced the overall GC content and the usage of G at the third codon position in the viral genome. Limited evidence of translational selection pressure was found in a few viral genes. Conclusions Codon usage patterns from CA allowed identification of host origin and evolutionary trends in influenza viruses, providing an alternative method and a tool to understand the evolution of influenza viruses. Human influenza viruses are subject to selection pressure on codon usage which might assist in understanding the characteristics of newly emerging viruses.

78 FR 46969 - Human Immunodeficiency Virus Patient-Focused Drug Development and Human Immunodeficiency Virus...

Science.gov (United States)

2013-08-02

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2013-N-0473] Human Immunodeficiency Virus Patient-Focused Drug Development and Human Immunodeficiency Virus Cure... for the notice of public meeting entitled ``Human Immunodeficiency Virus (HIV) Patient-Focused Drug...

Chimeric human parainfluenza virus bearing the Ebola virus glycoprotein as the sole surface protein is immunogenic and highly protective against Ebola virus challenge

International Nuclear Information System (INIS)

Bukreyev, Alexander; Marzi, Andrea; Feldmann, Friederike; Zhang Liqun; Yang Lijuan; Ward, Jerrold M.; Dorward, David W.; Pickles, Raymond J.; Murphy, Brian R.; Feldmann, Heinz; Collins, Peter L.

2009-01-01

We generated a new live-attenuated vaccine against Ebola virus (EBOV) based on a chimeric virus HPIV3/ΔF-HN/EboGP that contains the EBOV glycoprotein (GP) as the sole transmembrane envelope protein combined with the internal proteins of human parainfluenza virus type 3 (HPIV3). Electron microscopy analysis of the virus particles showed that they have an envelope and surface spikes resembling those of EBOV and a particle size and shape resembling those of HPIV3. When HPIV3/ΔF-HN/EboGP was inoculated via apical surface of an in vitro model of human ciliated airway epithelium, the virus was released from the apical surface; when applied to basolateral surface, the virus infected basolateral cells but did not spread through the tissue. Following intranasal (IN) inoculation of guinea pigs, scattered infected cells were detected in the lungs by immunohistochemistry, but infectious HPIV3/ΔF-HN/EboGP could not be recovered from the lungs, blood, or other tissues. Despite the attenuation, the virus was highly immunogenic, and a single IN dose completely protected the animals against a highly lethal intraperitoneal challenge of guinea pig-adapted EBOV

VIRUS instrument enclosures

Science.gov (United States)

Prochaska, T.; Allen, R.; Mondrik, N.; Rheault, J. P.; Sauseda, M.; Boster, E.; James, M.; Rodriguez-Patino, M.; Torres, G.; Ham, J.; Cook, E.; Baker, D.; DePoy, Darren L.; Marshall, Jennifer L.; Hill, G. J.; Perry, D.; Savage, R. D.; Good, J. M.; Vattiat, Brian L.

2014-08-01

The Visible Integral-Field Replicable Unit Spectrograph (VIRUS) instrument will be installed at the Hobby-Eberly Telescope† in the near future. The instrument will be housed in two enclosures that are mounted adjacent to the telescope, via the VIRUS Support Structure (VSS). We have designed the enclosures to support and protect the instrument, to enable servicing of the instrument, and to cool the instrument appropriately while not adversely affecting the dome environment. The system uses simple HVAC air handling techniques in conjunction with thermoelectric and standard glycol heat exchangers to provide efficient heat removal. The enclosures also provide power and data transfer to and from each VIRUS unit, liquid nitrogen cooling to the detectors, and environmental monitoring of the instrument and dome environments. In this paper, we describe the design and fabrication of the VIRUS enclosures and their subsystems.

Hepatitis A virus antibody

International Nuclear Information System (INIS)

Novak, J.; Kselikova, M.; Urbankova, J.

1980-01-01

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 125 I-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)

Avian influenza A virus and Newcastle disease virus mono- and co-infections in birds

Directory of Open Access Journals (Sweden)

Iv. Zarkov

2017-06-01

Full Text Available The main features of avian influenza viruses (AIV and Newcastle disease virus (APMV-1, the possibilities for isolation and identification in laboratory conditions, methods of diagnostics, main hosts, clinical signs and virus shedding are reviewed in chronological order. The other part of the review explains the mechanisms and interactions in cases of co-infection of AIV and APMV-1, either between them or with other pathogens in various indicator systems – cell cultures, chick embryos or birds. The emphasis is placed on quantitative data on the virus present mainly in the first ten days following experimental infection of birds, the periods of virus carrier ship and shedding, clinical signs, pathological changes, diagnostic challenges

BS-virus-finder

DEFF Research Database (Denmark)

Gao, Shengjie; Hu, Xuesong; Xu, Fengping

2018-01-01

Background: DNA methylation plays a key role in the regulation of gene expression and carcinogenesis. Bisulfite sequencing studies mainly focus on calling SNP, DMR, and ASM. Until now, only a few software tools focus on virus integration using bisulfite sequencing data. Findings: We have developed...... a new and easy-to-use software tool, named BS-virus-finder (BSVF, RRID:SCR_015727), to detect viral integration breakpoints in whole human genomes. The tool is hosted at https://github.com/BGI-SZ/BSVF. Conclusions: BS-virus-finder demonstrates high sensitivity and specificity. It is useful in epigenetic...

Ebola (Ebola Virus Disease): Diagnosis

Science.gov (United States)

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Ebola (Ebola Virus Disease): Transmission

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Ebola (Ebola Virus Disease): Treatment

Science.gov (United States)

... Search Form Controls Cancel Submit Search the CDC Ebola (Ebola Virus Disease) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Ebola (Ebola Virus Disease) What is Ebola Virus Disease? ...

Tomato ringspot virus and Tobacco ringspot virus in Highbush Blueberry in New York State

Science.gov (United States)

A survey of highbush blueberry (Vaccinium corymbosum L.) cultivars Patriot and Bluecrop showing virus-like symptoms and decline in vigor in New York was conducted to assess the occurrence of viruses. Leaf samples from symptomatic and asymptomatic bushes reacted positively to Tobacco ringspot virus ...

Protecting Anti-virus Programs From Viral Attacks

OpenAIRE

Mishra, Umakant

2013-01-01

During a fight between viruses and anti-viruses it is not always predictable that the anti-virus is going to win. There are many malicious viruses which target to attack and paralyze the anti-viruses. It is necessary for an anti-virus to detect and destroy the malware before its own files are detected and destroyed by the malware. The anti-virus may follow thorough testing and auditing procedures to fix all its bugs before releasing the software in the market. Besides the anti-virus may use a...

Remarkable morphological diversity of viruses and virus-like particles in hot terrestrial environments.

Science.gov (United States)

Rachel, R; Bettstetter, M; Hedlund, B P; Häring, M; Kessler, A; Stetter, K O; Prangishvili, D

2002-12-01

Electron microscopic studies of the viruses in two hot springs (85 degrees C, pH 1.5-2.0, and 75-93 degrees C, pH 6.5) in Yellowstone National Park revealed particles with twelve different morphotypes. This diversity encompassed known viruses of hyperthermophilic archaea, filamentous Lipothrixviridae, rod-shaped Rudiviridae, and spindle-shaped Fuselloviridae, and novel morphotypes previously not observed in nature. Two virus types resembled head-and-tail bacteriophages from the families Siphoviridae and Podoviridae, and constituted the first observation of these viruses in a hydrothermal environment. Viral hosts in the acidic spring were members of the hyperthermophilic archaeal genus Acidianus.

General properties of grapevine viruses occurring in Hungary

OpenAIRE

Eszter Cseh; András Takács; László Kocsis; Richard Gáborjányi

2012-01-01

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), Grape...

General properties of grapevine viruses occurring in Hungary

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Eszter Cseh

2012-03-01

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.

Control of sweet potato virus diseases.

Science.gov (United States)

Loebenstein, Gad

2015-01-01

Sweet potato (Ipomoea batatas) is ranked seventh in global food crop production and is the third most important root crop after potato and cassava. Sweet potatoes are vegetative propagated from vines, root slips (sprouts), or tubers. Therefore, virus diseases can be a major constrain, reducing yields markedly, often more than 50%. The main viruses worldwide are Sweet potato feathery mottle virus (SPFMV) and Sweet potato chlorotic stunt virus (SPCSV). Effects on yields by SPFMV or SPCSV alone are minor, or but in complex infection by the two or other viruses yield losses of 50%. The orthodox way of controlling viruses in vegetative propagated crops is by supplying the growers with virus-tested planting material. High-yielding plants are tested for freedom of viruses by PCR, serology, and grafting to sweet potato virus indicator plants. After this, meristem tips are taken from those plants that reacted negative. The meristems were grown into plants which were kept under insect-proof conditions and away from other sweet potato material for distribution to farmers after another cycle of reproduction. © 2015 Elsevier Inc. All rights reserved.

Autophagy in Measles Virus Infection

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Aurore Rozières

2017-11-01

Full Text Available Autophagy is a biological process that helps cells to recycle obsolete cellular components and which greatly contributes to maintaining cellular integrity in response to environmental stress factors. Autophagy is also among the first lines of cellular defense against invading microorganisms, including viruses. The autophagic destruction of invading pathogens, a process referred to as xenophagy, involves cytosolic autophagy receptors, such as p62/SQSTM1 (Sequestosome 1 or NDP52/CALCOCO2 (Nuclear Dot 52 KDa Protein/Calcium Binding And Coiled-Coil Domain 2, which bind to microbial components and target them towards growing autophagosomes for degradation. However, most, if not all, infectious viruses have evolved molecular tricks to escape from xenophagy. Many viruses even use autophagy, part of the autophagy pathway or some autophagy-associated proteins, to improve their infectious potential. In this regard, the measles virus, responsible for epidemic measles, has a unique interface with autophagy as the virus can induce multiple rounds of autophagy in the course of infection. These successive waves of autophagy result from distinct molecular pathways and seem associated with anti- and/or pro-measles virus consequences. In this review, we describe what the autophagy–measles virus interplay has taught us about both the biology of the virus and the mechanistic orchestration of autophagy.

Strategy as a Virus

DEFF Research Database (Denmark)

Obed Madsen, Søren

This article is based on virus theory (Røvik, 2007, 2011), and proposes to develop a framework that defines technology as a virus that penetrates the organism of an organization. The framework develops a new vocabulary, which can help in analyzing technologies and their negative effects on actors...... and organizations. In this paper, the virus theory is used to analyze a strategy process in an organization as an example of a technology. It shows how the strategy over time creates a memory loss, where the managers who are exposed to the virus forget their critique of the new strategy concept. The article also...... shows how resistant can be understood as being immune to a virus, since the strategy concepts bears resemblance to a former strategy concept. The article also argues that there should be more focus on the negative impacts of management tool and especially how organizations and managers are dealing...

Plant virus sensitivity to gamma irradiation

International Nuclear Information System (INIS)

Gyoergyne Czeck, B.

1979-01-01

Preliminary experiments for prevention were conducted with weakened plant viruses, namely with Arabis mosaic virus isolated from strawberries and tobacco mosaic virus. Treatment 24 hours prior to the infection with the radiation-weakened virus resulted in a 60-70% infection prevention. (author)

Unprecedented genomic diversity of RNA viruses in arthropods reveals the ancestry of negative-sense RNA viruses.

Science.gov (United States)

Li, Ci-Xiu; Shi, Mang; Tian, Jun-Hua; Lin, Xian-Dan; Kang, Yan-Jun; Chen, Liang-Jun; Qin, Xin-Cheng; Xu, Jianguo; Holmes, Edward C; Zhang, Yong-Zhen

2015-01-29

Although arthropods are important viral vectors, the biodiversity of arthropod viruses, as well as the role that arthropods have played in viral origins and evolution, is unclear. Through RNA sequencing of 70 arthropod species we discovered 112 novel viruses that appear to be ancestral to much of the documented genetic diversity of negative-sense RNA viruses, a number of which are also present as endogenous genomic copies. With this greatly enriched diversity we revealed that arthropods contain viruses that fall basal to major virus groups, including the vertebrate-specific arenaviruses, filoviruses, hantaviruses, influenza viruses, lyssaviruses, and paramyxoviruses. We similarly documented a remarkable diversity of genome structures in arthropod viruses, including a putative circular form, that sheds new light on the evolution of genome organization. Hence, arthropods are a major reservoir of viral genetic diversity and have likely been central to viral evolution.

Protection against myxomatosis and rabbit viral hemorrhagic disease with recombinant myxoma viruses expressing rabbit hemorrhagic disease virus capsid protein.

Science.gov (United States)

Bertagnoli, S; Gelfi, J; Le Gall, G; Boilletot, E; Vautherot, J F; Rasschaert, D; Laurent, S; Petit, F; Boucraut-Baralon, C; Milon, A

1996-08-01

Two myxoma virus-rabbit hemorrhagic disease virus (RHDV) recombinant viruses were constructed with the SG33 strain of myxoma virus to protect rabbits against myxomatosis and rabbit viral hemorrhagic disease. These recombinant viruses expressed the RHDV capsid protein (VP60). The recombinant protein, which is 60 kDa in size, was antigenic, as revealed by its reaction in immunoprecipitation with antibodies raised against RHDV. Both recombinant viruses induced high levels of RHDV- and myxoma virus-specific antibodies in rabbits after immunization. Inoculations by the intradermal route protected animals against virulent RHDV and myxoma virus challenges.

A Literature Review of Zika Virus.

Science.gov (United States)

Plourde, Anna R; Bloch, Evan M

2016-07-01

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.

Soroprevalência e fatores de risco para a língua azul em carneiros das mesorregiões do Sertão e da Borborema, semi-árido do Estado da Paraíba, Brasil Seroprevalence and risk factors for Bluetongue in rams of the Sertão and Borborema mesoregions, semi-arid of Paraíba state, Northeastern Brazil

Directory of Open Access Journals (Sweden)

Francisco de Assis Leandro Alves

2009-04-01

Full Text Available Neste estudo foi determinada a prevalência de anticorpos contra o vírus da língua azul em carneiros das mesorregiões do Sertão e da Borborema, semi-árido do Estado da Paraíba, bem como foram identificados os fatores de risco associados à infecção. A amostragem foi delineada para a determinação da prevalência de propriedades positivas (focos e de animais soropositivos por mesorregião. Foi realizada uma seleção aleatória de unidades primárias, composta por 189 propriedades no Sertão e 100 propriedades na Borborema. Dentro das unidades primárias, foram amostrados todos os carneiros (unidades secundárias, resultando em 321 animais no Sertão e 185 na Borborema. Na ocasião da coleta, foi aplicado um questionário epidemiológico por propriedade. Para o diagnóstico sorológico, foi utilizada a prova de imunodifusão em gel de ágar (IDGA, com antígeno produzido na Escola de Veterinária da Universidade Federal de Minas Gerais. Uma propriedade foi considerada foco quando apresentou pelo menos um animal soropositivo. Na mesorregião do Sertão, as prevalências de focos e de animais soropositivos foram de 11,6% [7,8% - 17,1%] e 8,4% [5,7% - 12,3%], respectivamente. Na mesorregião da Borborema, a prevalência de focos foi de 0,0% [0,0% - 3,6%] e a prevalência de animais soropositivos foi de 0,0% [0,0% - 2,0%]. Os fatores de risco associados à língua azul foram a não realização de higiene das instalações (OR = 5,51 e a vermifugação dos animais duas a quatro vezes ao ano (OR = 4,44.The prevalence of antibodies against Bluetongue virus in rams of the Sertão and Borborema mesoregions, semi-arid of the Paraíba state, Northeastern Brazil, was determined, and risk factors for the infection were identified. The sampling was delineated for the determination of the prevalence of positive herds and seropositive animals for each mesoregion. Herds (primary units were randomly selected in the Sertão mesoregion (n = 189 and in the

Tobacco ringspot virus

Science.gov (United States)

Tobacco ringspot virus (TRSV), and its vector, the dagger nematodes (Xiphinema americanum and related species) are widely distributed throughout the world. Cucumber, melon, and watermelon are particularly affected by TRSV. Symptoms can vary with plant age, the strain of the virus, and environment...

Viruses affecting lentil (Lens culinaris Medik. in Greece; incidence and genetic variability of Bean leafroll virus and Pea enation mosaic virus

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Elisavet K. CHATZIVASSILIOU

2016-07-01

Full Text Available In Greece, lentil (Lens culinaris Medik. crops are mainly established with non-certified seeds of local landraces, implying high risks for seed transmitted diseases. During April and May of the 2007–2012 growing seasons, surveys were conducted in eight regions of Greece (Attiki, Evros, Fthiotida, Korinthos, Kozani, Larissa, Lefkada and Viotia to monitor virus incidence in lentil fields. A total of 1216 lentil samples, from plants exhibiting symptoms suggestive of virus infection, were analyzed from 2007 to 2009, using tissue-blot immunoassays (TBIA. Pea seed-borne mosaic virus (PSbMV overall incidence was 4.9%, followed by Alfalfa mosaic virus (AMV (2.4% and Bean yellow mosaic virus (BYMV (1.0%. When 274 of the samples were tested for the presence of luteoviruses, 38.8% were infected with Bean leafroll virus (BLRV. Since BLRV was not identified in the majority of the samples collected from 2007 to 2009, representative symptomatic plants (360 samples were collected in further surveys performed from 2010 to 2012 and tested by ELISA. Two viruses prevailed in those samples: BLRV (36.1% was associated with stunting, yellowing, and reddening symptoms and Pea enation mosaic virus-1 (PEMV-1 (35.0% was associated with mosaic and mottling symptoms. PSbMV (2.2%, AMV (2.2%, BYMV (3.9% and CMV (2.8% were also detected. When the molecular variability was analyzed for representative isolates, collected from the main Greek lentil production areas, five BLRV isolates showed 95% identity for the coat protein (CP gene and 99% for the 3’ end region. Three Greek PEMV isolates co-clustered with an isolate from Germany when their CP sequence was compared with isolates with no mutation in the aphid transmission gene. Overall, limited genetic variability was detected among Greek isolates of BLRV and PEMV.

Virus-neutralizing antibody response of mice to consecutive infection with human and avian influenza A viruses.

Science.gov (United States)

Janulíková, J; Stropkovská, A; Bobišová, Z; Košík, I; Mucha, V; Kostolanský, F; Varečková, E

2015-06-01

In this work we simulated in a mouse model a naturally occurring situation of humans, who overcame an infection with epidemic strains of influenza A, and were subsequently exposed to avian influenza A viruses (IAV). The antibody response to avian IAV in mice previously infected with human IAV was analyzed. We used two avian IAV (A/Duck/Czechoslovakia/1956 (H4N6) and the attenuated virus rA/Viet Nam/1203-2004 (H5N1)) as well as two human IAV isolates (virus A/Mississippi/1/1985 (H3N2) of medium virulence and A/Puerto Rico/8/1934 (H1N1) of high virulence). Two repeated doses of IAV of H4 or of H5 virus elicited virus-specific neutralizing antibodies in mice. Exposure of animals previously infected with human IAV (of H3 or H1 subtype) to IAV of H4 subtype led to the production of antibodies neutralizing H4 virus in a level comparable with the level of antibodies against the human IAV used for primary infection. In contrast, no measurable levels of virus-neutralizing (VN) antibodies specific to H5 virus were detected in mice infected with H5 virus following a previous infection with human IAV. In both cases the secondary infection with avian IAV led to a significant increase of the titer of VN antibodies specific to the corresponding human virus used for primary infection. Moreover, cross-reactive HA2-specific antibodies were also induced by sequential infection. By virtue of these results we suggest that the differences in the ability of avian IAV to induce specific antibodies inhibiting virus replication after previous infection of mice with human viruses can have an impact on the interspecies transmission and spread of avian IAV in the human population.

Differential diagnosis of feline leukemia virus subgroups using pseudotype viruses expressing green fluorescent protein.

Science.gov (United States)

Nakamura, Megumi; Sato, Eiji; Miura, Tomoyuki; Baba, Kenji; Shimoda, Tetsuya; Miyazawa, Takayuki

2010-06-01

Feline leukemia virus (FeLV) is classified into three receptor interference subgroups, A, B and C. In this study, to differentiate FeLV subgroups, we developed a simple assay system using pseudotype viruses expressing green fluorescent protein (GFP). We prepared gfp pseudotype viruses, named gfp(FeLV-A), gfp(FeLV-B) and gfp(FeLV-C) harboring envelopes of FeLV-A, B and C, respectively. The gfp pseudotype viruses completely interfered with the same subgroups of FeLV reference strains on FEA cells (a feline embryonic fibroblast cell line). We also confirmed that the pseudotype viruses could differentiate FeLV subgroups in field isolates. The assay will be useful for differential diagnosis of FeLV subgroups in veterinary diagnostic laboratories in the future.

Interventions Against West Nile Virus, Rift Valley Fever Virus, and Crimean-Congo Hemorrhagic Fever Virus: Where Are We?

NARCIS (Netherlands)

Kortekaas, J.A.; Ergonul, O.; Moormann, R.J.M.

2010-01-01

ARBO-ZOONET is an international network financed by the European Commission's seventh framework program. The major goal of this initiative is capacity building for the control of emerging viral vector-borne zoonotic diseases, with a clear focus on West Nile virus, Rift Valley fever virus, and

West Nile virus: North American experience

Science.gov (United States)

Hofmeister, Erik K.

2011-01-01

West Nile virus, a mosquito-vectored flavivirus of the Japanese encephalitis serogroup, was first detected in North America following an epizootic in the New York City area in 1999. In the intervening 11 years since the arrival of the virus in North America, it has crossed the contiguous USA, entered the Canadian provinces bordering the USA, and has been reported in the Caribbean islands, Mexico, Central America and, more recently, South America. West Nile virus has been reported in over 300 species of birds in the USA and has caused the deaths of thousands of birds, local population declines of some avian species, the clinical illness and deaths of thousands of domestic horses, and the clinical disease in over 30 000 Americans and the deaths of over 1000. Prior to the emergence of West Nile virus in North America, St. Louis encephalitis virus and Dengue virus were the only other known mosquito-transmitted flaviviruses in North America capable of causing human disease. This review will discuss the North American experience with mosquito-borne flavivirus prior to the arrival of West Nile virus, the entry and spread of West Nile virus in North America, effects on wild bird populations, genetic changes in the virus, and the current state of West Nile virus transmission.

Drosophila Nora virus capsid proteins differ from those of other picorna-like viruses.

Science.gov (United States)

Ekström, Jens-Ola; Habayeb, Mazen S; Srivastava, Vaibhav; Kieselbach, Thomas; Wingsle, Gunnar; Hultmark, Dan

2011-09-01

The recently discovered Nora virus from Drosophila melanogaster is a single-stranded RNA virus. Its published genomic sequence encodes a typical picorna-like cassette of replicative enzymes, but no capsid proteins similar to those in other picorna-like viruses. We have now done additional sequencing at the termini of the viral genome, extending it by 455 nucleotides at the 5' end, but no more coding sequence was found. The completeness of the final 12,333-nucleotide sequence was verified by the production of infectious virus from the cloned genome. To identify the capsid proteins, we purified Nora virus particles and analyzed their proteins by mass spectrometry. Our results show that the capsid is built from three major proteins, VP4A, B and C, encoded in the fourth open reading frame of the viral genome. The viral particles also contain traces of a protein from the third open reading frame, VP3. VP4A and B are not closely related to other picorna-like virus capsid proteins in sequence, but may form similar jelly roll folds. VP4C differs from the others and is predicted to have an essentially α-helical conformation. In a related virus, identified from EST database sequences from Nasonia parasitoid wasps, VP4C is encoded in a separate open reading frame, separated from VP4A and B by a frame-shift. This opens a possibility that VP4C is produced in non-equimolar quantities. Altogether, our results suggest that the Nora virus capsid has a different protein organization compared to the order Picornavirales. Copyright © 2011 Elsevier B.V. All rights reserved.