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Sample records for equine encephalitis viruses

  1. Eastern Equine Encephalitis Virus

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    Borucki, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2010-08-05

    Eastern equine encephalitis virus (EEEV) is a mosquito-borne virus capable of causing large outbreaks of encephalitis in humans and horses. In North America, EEEV infection has a very high mortality rate in humans, and survivors often suffer severe neurological sequelae. Interestingly, EEEV infections from South American isolates are generally subclinical. Although EEEV is divided into two antigenic varieties and four lineages, only eleven isolates have been sequenced and eight of these are from the North American variety (Lineage I). Most sequenced strains were collected from mosquitoes and only one human isolate has been sequenced. EEEV isolates exist from a variety of hosts, vectors, years, and geographical locations and efforts should focus on sequencing strains that represent this diversity.

  2. Testosterone correlates with Venezuelan equine encephalitis virus infection in macaques

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    Koterski James

    2006-03-01

    Full Text Available Abstract Here we briefly report testosterone and cytokine responses to Venezuelan equine encephalitis virus (VEEV in macaques which were used as part of a larger study conducted by the Department of Defense to better characterize pathological responses to aerosolized VEEV in non-human primates. Serial samples were collected and analyzed for testosterone and cytokines prior to and during infection in 8 captive male macaques. Infected animals exhibited a febrile response with few significant changes in cytokine levels. Baseline testosterone levels were positively associated with viremia following exposure and were significantly higher than levels obtained during infection. Such findings suggest that disease-induced androgen suppression is a reasonable area for future study. Decreased androgen levels during physiological perturbations may function, in part, to prevent immunosuppression by high testosterone levels and to prevent the use of energetic resources for metabolically-expensive anabolic functions.

  3. Rabies direct fluorescent antibody test does not inactivate rabies or eastern equine encephalitis viruses.

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    Jarvis, Jodie A; Franke, Mary A; Davis, April D

    2016-08-01

    An examination using the routine rabies direct fluorescent antibody test was performed on rabies or Eastern equine encephalitis positive mammalian brain tissue to assess inactivation of the virus. Neither virus was inactivated with acetone fixation nor the routine test, thus laboratory employees should treat all samples as rabies and when appropriate Eastern equine encephalitis positive throughout the whole procedure. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Venezuelan equine encephalitis virus infection causes modulation of inflammatory and immune response genes in mouse brain

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    Sharma, Anuj; Bhattacharya, Bhaskar; Puri, Raj K; Maheshwari, Radha K

    2008-01-01

    Abstract Background Neurovirulent Venezuelan equine encephalitis virus (VEEV) causes lethal encephalitis in equines and is transmitted to humans by mosquitoes. VEEV is highly infectious when transmitted by aerosol and has been developed as a bio-warfare agent, making it an important pathogen to study from a military and civilian standpoint. Molecular mechanisms of VEE pathogenesis are poorly understood. To study these, the gene expression profile of VEEV infected mouse brains was investigated...

  5. Replicon particles of Venezuelan equine encephalitis virus as a reductionist murine model for encephalitis.

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    Schäfer, Alexandra; Whitmore, Alan C; Konopka, Jennifer L; Johnston, Robert E

    2009-05-01

    Venezuelan equine encephalitis virus (VEE) replicon particles (VRP) were used to model the initial phase of VEE-induced encephalitis in the mouse brain. VRP can target and infect cells as VEE, but VRP do not propagate beyond the first infected cell due to the absence of the structural genes. Direct intracranial inoculation of VRP into mice induced acute encephalitis with signs similar to the neuronal phase of wild-type VEE infection and other models of virus-induced encephalitis. Using the previously established VRP-mRNP tagging system, a new method to distinguish the host responses in infected cells from those in uninfected bystander cell populations, we detected a robust and rapid innate immune response in the central nervous system (CNS) by infected neurons and uninfected bystander cells. Moreover, this innate immune response in the CNS compromised blood-brain barrier integrity, created an inflammatory response, and directed an adaptive immune response characterized by proliferation and activation of microglia cells and infiltration of inflammatory monocytes, in addition to CD4(+) and CD8(+) T lymphocytes. Taken together, these data suggest that a naïve CNS has an intrinsic potential to induce an innate immune response that could be crucial to the outcome of the infection by determining the composition and dynamics of the adaptive immune response. Furthermore, these results establish a model for neurotropic virus infection to identify host and viral factors that contribute to invasion of the brain, the mechanism(s) whereby the adaptive immune response can clear the infection, and the role of the host innate response in these processes.

  6. Eastern Equine Encephalitis

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    ... bite of an infected mosquito. Eastern equine encephalitis (EEE) is a rare illness in humans, and only ... EEEV have no apparent illness. Severe cases of EEE (involving encephalitis, an inflammation of the brain) begin ...

  7. West nile virus and equine encephalitis viruses: new perspectives.

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    Long, Maureen T

    2014-12-01

    Mosquito-borne diseases affect horses worldwide. Mosquito-borne diseases generally cause encephalomyelitis in the horse and can be difficult to diagnose antemortem. In addition to general disease, and diagnostic and treatment aspects, this review article summarizes the latest information on these diseases, covering approximately the past 5 years, with a focus on new equine disease encroachments, diagnostic and vaccination aspects, and possible therapeutics on the horizon. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Field Investigations of Winter Transmission of Eastern Equine Encephalitis Virus in Florida

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    Bingham, Andrea M.; Burkett-Cadena, Nathan D.; HASSAN, HASSAN K.; McClure, Christopher J.W.; Unnasch, Thomas R

    2014-01-01

    Studies investigating winter transmission of Eastern equine encephalitis virus (EEEV) were conducted in Hillsborough County, Florida. The virus was detected in Culiseta melanura and Anopheles quadrimaculatus in February 2012 and 2013, respectively. During the winter months, herons were the most important avian hosts for all mosquito species encountered. In collections carried out in the summer of 2011, blood meals taken from herons were still common, but less frequently encountered than in wi...

  9. Venezuelan Equine Encephalitis Virus Activity in the Gulf Coast Region of Mexico, 2003–2010

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    Adams, A. Paige; Navarro-Lopez, Roberto; Ramirez-Aguilar, Francisco J.; Lopez-Gonzalez, Irene; Leal, Grace; Flores-Mayorga, Jose M.; Travassos da Rosa, Amelia P. A.; Saxton-Shaw, Kali D.; Singh, Amber J.; Borland, Erin M.; Powers, Ann M.; Tesh, Robert B.; Weaver, Scott C.; Estrada-Franco, Jose G.

    2012-01-01

    Venezuelan equine encephalitis virus (VEEV) has been the causative agent for sporadic epidemics and equine epizootics throughout the Americas since the 1930s. In 1969, an outbreak of Venezuelan equine encephalitis (VEE) spread rapidly from Guatemala and through the Gulf Coast region of Mexico, reaching Texas in 1971. Since this outbreak, there have been very few studies to determine the northward extent of endemic VEEV in this region. This study reports the findings of serologic surveillance in the Gulf Coast region of Mexico from 2003–2010. Phylogenetic analysis was also performed on viral isolates from this region to determine whether there have been substantial genetic changes in VEEV since the 1960s. Based on the findings of this study, the Gulf Coast lineage of subtype IE VEEV continues to actively circulate in this region of Mexico and appears to be responsible for infection of humans and animals throughout this region, including the northern State of Tamaulipas, which borders Texas. PMID:23133685

  10. Demographics of natural oral infection of mosquitos by Venezuelan equine encephalitis virus.

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    Gutiérrez, Serafín; Thébaud, Gaël; Smith, Darci R; Kenney, Joan L; Weaver, Scott C

    2015-04-01

    The within-host diversity of virus populations can be drastically limited during between-host transmission, with primary infection of hosts representing a major constraint to diversity maintenance. However, there is an extreme paucity of quantitative data on the demographic changes experienced by virus populations during primary infection. Here, the multiplicity of cellular infection (MOI) and population bottlenecks were quantified during primary mosquito infection by Venezuelan equine encephalitis virus, an arbovirus causing neurological disease in humans and equids. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  11. The ubiquitin proteasome system plays a role in venezuelan equine encephalitis virus infection.

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    Moushimi Amaya

    Full Text Available Many viruses have been implicated in utilizing or modulating the Ubiquitin Proteasome System (UPS to enhance viral multiplication and/or to sustain a persistent infection. The mosquito-borne Venezuelan equine encephalitis virus (VEEV belongs to the Togaviridae family and is an important biodefense pathogen and select agent. There are currently no approved vaccines or therapies for VEEV infections; therefore, it is imperative to identify novel targets for therapeutic development. We hypothesized that a functional UPS is required for efficient VEEV multiplication. We have shown that at non-toxic concentrations Bortezomib, a FDA-approved inhibitor of the proteasome, proved to be a potent inhibitor of VEEV multiplication in the human astrocytoma cell line U87MG. Bortezomib inhibited the virulent Trinidad donkey (TrD strain and the attenuated TC-83 strain of VEEV. Additional studies with virulent strains of Eastern equine encephalitis virus (EEEV and Western equine encephalitis virus (WEEV demonstrated that Bortezomib is a broad spectrum inhibitor of the New World alphaviruses. Time-of-addition assays showed that Bortezomib was an effective inhibitor of viral multiplication even when the drug was introduced many hours post exposure to the virus. Mass spectrometry analyses indicated that the VEEV capsid protein is ubiquitinated in infected cells, which was validated by confocal microscopy and immunoprecipitation assays. Subsequent studies revealed that capsid is ubiquitinated on K48 during early stages of infection which was affected by Bortezomib treatment. This study will aid future investigations in identifying host proteins as potential broad spectrum therapeutic targets for treating alphavirus infections.

  12. Candidate Vectors and Rodent Hosts of Venezuelan Equine Encephalitis Virus, Chiapas, 2006–2007

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    Deardorff, Eleanor R.; Estrada-Franco, Jose G.; Freier, Jerome E.; Navarro-Lopez, Roberto; Da Rosa, Amelia Travassos; Tesh, Robert B.; Weaver, Scott C.

    2011-01-01

    Enzootic Venezuelan equine encephalitis virus (VEEV) has been known to occur in Mexico since the 1960s. The first natural equine epizootic was recognized in Chiapas in 1993 and since then, numerous studies have characterized the etiologic strains, including reverse genetic studies that incriminated a specific mutation that enhanced infection of epizootic mosquito vectors. The aim of this study was to determine the mosquito and rodent species involved in enzootic maintenance of subtype IE VEEV in coastal Chiapas. A longitudinal study was conducted over a year to discern which species and habitats could be associated with VEEV circulation. Antibody was rarely detected in mammals and virus was not isolated from mosquitoes. Additionally, Culex (Melanoconion) taeniopus populations were found to be spatially related to high levels of human and bovine seroprevalence. These mosquito populations were concentrated in areas that appear to represent foci of stable, enzootic VEEV circulation. PMID:22144461

  13. Eastern equine encephalitis.

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    Berlin, Daniel; Gilani, Ahmed I; Grewal, Amrit K; Fowkes, Mary

    2017-10-01

    We describe a patient who died from a fulminant presentation of encephalitis. After an exhaustive search, we found no treatable cause. Postmortem PCR analysis of brain tissue led to a diagnosis of eastern equine encephalitis. We have identified several clinical pearls that may assist others in making the diagnosis earlier in the disease course. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  14. Replicon Particles of Venezuelan Equine Encephalitis Virus as a Reductionist Murine Model for Encephalitis▿

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    Schäfer, Alexandra; Whitmore, Alan C.; Konopka, Jennifer L.; Johnston, Robert E.

    2009-01-01

    Venezuelan equine encephalitis virus (VEE) replicon particles (VRP) were used to model the initial phase of VEE-induced encephalitis in the mouse brain. VRP can target and infect cells as VEE, but VRP do not propagate beyond the first infected cell due to the absence of the structural genes. Direct intracranial inoculation of VRP into mice induced acute encephalitis with signs similar to the neuronal phase of wild-type VEE infection and other models of virus-induced encephalitis. Using the previously established VRP-mRNP tagging system, a new method to distinguish the host responses in infected cells from those in uninfected bystander cell populations, we detected a robust and rapid innate immune response in the central nervous system (CNS) by infected neurons and uninfected bystander cells. Moreover, this innate immune response in the CNS compromised blood-brain barrier integrity, created an inflammatory response, and directed an adaptive immune response characterized by proliferation and activation of microglia cells and infiltration of inflammatory monocytes, in addition to CD4+ and CD8+ T lymphocytes. Taken together, these data suggest that a naïve CNS has an intrinsic potential to induce an innate immune response that could be crucial to the outcome of the infection by determining the composition and dynamics of the adaptive immune response. Furthermore, these results establish a model for neurotropic virus infection to identify host and viral factors that contribute to invasion of the brain, the mechanism(s) whereby the adaptive immune response can clear the infection, and the role of the host innate response in these processes. PMID:19225006

  15. Development of a Genetically Engineered Venezuelan Equine Encephalitis Virus Vaccine

    Science.gov (United States)

    1991-04-15

    contributes to the virulence of TRD virus. To determine the contribution which the TRD 5’-noncoding region makes to virulence and the synergism between... chloramphenicol acetyl transferase gene by DEAE-dextran medicated DNA transfection coupled with a dimethyl sulfoxide or glycerol shock treatment. Nucleic Acids

  16. Field investigations of winter transmission of eastern equine encephalitis virus in Florida.

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    Bingham, Andrea M; Burkett-Cadena, Nathan D; Hassan, Hassan K; McClure, Christopher J W; Unnasch, Thomas R

    2014-10-01

    Studies investigating winter transmission of Eastern equine encephalitis virus (EEEV) were conducted in Hillsborough County, Florida. The virus was detected in Culiseta melanura and Anopheles quadrimaculatus in February 2012 and 2013, respectively. During the winter months, herons were the most important avian hosts for all mosquito species encountered. In collections carried out in the summer of 2011, blood meals taken from herons were still common, but less frequently encountered than in winter, with an increased frequency of mammalian- and reptile-derived meals observed in the summer. Four wading bird species (Black-crowned Night Heron [Nycticorax nycticorax], Yellow-crowned Night Heron [Nyctanassa violacea], Anhinga [Anhinga anhinga], and Great Blue Heron [Ardea herodias]) were most frequently fed upon by Cs. melanura and Culex erraticus, suggesting that these species may participate in maintaining EEEV during the winter in Florida. © The American Society of Tropical Medicine and Hygiene.

  17. Eastern equine encephalitis virus: high seroprevalence in horses from Southern Quebec, Canada, 2012.

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    Rocheleau, Jean-Philippe; Arsenault, Julie; Lindsay, L Robbin; DiBernardo, Antonia; Kulkarni, Manisha A; Côté, Nathalie; Michel, Pascal

    2013-10-01

    Eastern equine encephalitis virus (EEEV) is a highly pathogenic arbovirus that infects humans, horses, and other animals. There has been a significant increase in EEEV activity in southeastern Canada since 2008. Few data are available regarding nonlethal EEEV infections in mammals, and consequently the distribution and pathogenicity spectrum of EEEV infections in these hosts is poorly understood. This cross-sectional study focuses on the evaluation of viral activity in southern Quebec's horses by seroprevalence estimation. A total of 196 horses, 18 months and older, which had never been vaccinated against EEEV and have never traveled outside Canada, were sampled from 92 barns distributed throughout three administrative regions of southern Quebec. Blood samples were taken from each horse and titrated for EEEV antibodies by plaque reduction neutralization test (PRNT). Equine population vaccination coverage was estimated by surveying horse owners and equine practitioners. PRNT results revealed an EEEV seroprevalence up to 8.7%, with 95% confidence limits ranging from 4.4% to 13.0%. Vaccination coverage was estimated to be at least 79%. Our study reveals for the first time in Canada a measure of EEEV seroprevalence in horses. High seroprevalence in unvaccinated animals challenges the perception that EEEV is a highly lethal pathogen in horses. Monitoring high-risk vector-borne infections such as EEEV in animal populations can be an important element of a public health surveillance strategy, population risk assessment and early detection of epidemics.

  18. Serosurveillance of Eastern Equine Encephalitis Virus in Amphibians and Reptiles from Alabama, USA

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    Graham, Sean P.; Hassan, Hassan K.; Chapman, Taryn; White, Gregory; Guyer, Craig; Unnasch, Thomas R.

    2012-01-01

    Eastern equine encephalitis virus (EEEV) is among the most medically important arboviruses in North America, and studies suggest a role for amphibians and reptiles in its transmission cycle. Serum samples collected from 351 amphibians and reptiles (27 species) from Alabama, USA, were tested for the presence of antibodies against EEEV. Frogs, turtles, and lizards showed little or no seropositivity, and snakes had high seropositivity rates. Most seropositive species were preferred or abundant hosts of Culex spp. mosquitoes at Tuskegee National Forest, that target ectothermic hosts. The cottonmouth, the most abundant ectotherm sampled, displayed a high prevalence of seropositivity, indicating its possible role as an amplification and/or over-wintering reservoir for EEEV. PMID:22403333

  19. Venezuelan Equine Encephalitis Viruses (VEEV) in Argentina: Serological Evidence of Human Infection

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    Pisano, María Belén; Oria, Griselda; Beskow, Geraldine; Aguilar, Javier; Konigheim, Brenda; Cacace, María Luisa; Aguirre, Luis; Stein, Marina; Contigiani, Marta Silvia

    2013-01-01

    Venezuelan equine encephalitis viruses (VEEV) are responsible for human diseases in the Americas, producing severe or mild illness with symptoms indistinguishable from dengue and other arboviral diseases. For this reason, many cases remain without certain diagnosis. Seroprevalence studies for VEEV subtypes IAB, ID, IF (Mosso das Pedras virus; MDPV), IV (Pixuna virus; PIXV) and VI (Rio Negro virus; RNV) were conducted in persons from Northern provinces of Argentina: Salta, Chaco and Corrientes, using plaque reduction neutralization test (PRNT). RNV was detected in all studied provinces. Chaco presented the highest prevalence of this virus (14.1%). Antibodies against VEEV IAB and -for the first time- against MDPV and PIXV were also detected in Chaco province. In Corrientes, seroprevalence against RNV was 1.3% in the pediatric population, indicating recent infections. In Salta, this was the first investigation of VEEV members, and antibodies against RNV and PIXV were detected. These results provide evidence of circulation of many VEE viruses in Northern Argentina, showing that surveillance of these infectious agents should be intensified. PMID:24349588

  20. Venezuelan equine encephalitis viruses (VEEV in Argentina: serological evidence of human infection.

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    María Belén Pisano

    Full Text Available Venezuelan equine encephalitis viruses (VEEV are responsible for human diseases in the Americas, producing severe or mild illness with symptoms indistinguishable from dengue and other arboviral diseases. For this reason, many cases remain without certain diagnosis. Seroprevalence studies for VEEV subtypes IAB, ID, IF (Mosso das Pedras virus; MDPV, IV (Pixuna virus; PIXV and VI (Rio Negro virus; RNV were conducted in persons from Northern provinces of Argentina: Salta, Chaco and Corrientes, using plaque reduction neutralization test (PRNT. RNV was detected in all studied provinces. Chaco presented the highest prevalence of this virus (14.1%. Antibodies against VEEV IAB and -for the first time- against MDPV and PIXV were also detected in Chaco province. In Corrientes, seroprevalence against RNV was 1.3% in the pediatric population, indicating recent infections. In Salta, this was the first investigation of VEEV members, and antibodies against RNV and PIXV were detected. These results provide evidence of circulation of many VEE viruses in Northern Argentina, showing that surveillance of these infectious agents should be intensified.

  1. Infected dendritic cells are sufficient to mediate the adjuvant activity generated by Venezuelan equine encephalitis virus replicon particles

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    Tonkin, Daniel R; Whitmore, Alan; Johnston, Robert E; Barro, Mario

    2012-01-01

    Replicon particles derived from Venezuelan equine encephalitis virus (VEE) are infectious non-propagating particles which act as a safe and potent systemic, mucosal, and cellular adjuvant when delivered with antigen. VEE and VEE replicon particles (VRP) can target multiple cell types including dendritic cells (DCs). The role of these cell types in VRP adjuvant activity has not been previously evaluated, and for these studies we focused on the contribution of DCs to the response to VRP. By ana...

  2. Discovery of a novel compound with anti-venezuelan equine encephalitis virus activity that targets the nonstructural protein 2.

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    Dong-Hoon Chung

    2014-06-01

    Full Text Available Alphaviruses present serious health threats as emerging and re-emerging viruses. Venezuelan equine encephalitis virus (VEEV, a New World alphavirus, can cause encephalitis in humans and horses, but there are no therapeutics for treatment. To date, compounds reported as anti-VEEV or anti-alphavirus inhibitors have shown moderate activity. To discover new classes of anti-VEEV inhibitors with novel viral targets, we used a high-throughput screen based on the measurement of cell protection from live VEEV TC-83-induced cytopathic effect to screen a 340,000 compound library. Of those, we identified five novel anti-VEEV compounds and chose a quinazolinone compound, CID15997213 (IC50 = 0.84 µM, for further characterization. The antiviral effect of CID15997213 was alphavirus-specific, inhibiting VEEV and Western equine encephalitis virus, but not Eastern equine encephalitis virus. In vitro assays confirmed inhibition of viral RNA, protein, and progeny synthesis. No antiviral activity was detected against a select group of RNA viruses. We found mutations conferring the resistance to the compound in the N-terminal domain of nsP2 and confirmed the target residues using a reverse genetic approach. Time of addition studies showed that the compound inhibits the middle stage of replication when viral genome replication is most active. In mice, the compound showed complete protection from lethal VEEV disease at 50 mg/kg/day. Collectively, these results reveal a potent anti-VEEV compound that uniquely targets the viral nsP2 N-terminal domain. While the function of nsP2 has yet to be characterized, our studies suggest that the protein might play a critical role in viral replication, and further, may represent an innovative opportunity to develop therapeutic interventions for alphavirus infection.

  3. Discovery of a novel compound with anti-venezuelan equine encephalitis virus activity that targets the nonstructural protein 2.

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    Chung, Dong-Hoon; Jonsson, Colleen B; Tower, Nichole A; Chu, Yong-Kyu; Sahin, Ergin; Golden, Jennifer E; Noah, James W; Schroeder, Chad E; Sotsky, Julie B; Sosa, Melinda I; Cramer, Daniel E; McKellip, Sara N; Rasmussen, Lynn; White, E Lucile; Schmaljohn, Connie S; Julander, Justin G; Smith, Jeffrey M; Filone, Claire Marie; Connor, John H; Sakurai, Yasuteru; Davey, Robert A

    2014-06-01

    Alphaviruses present serious health threats as emerging and re-emerging viruses. Venezuelan equine encephalitis virus (VEEV), a New World alphavirus, can cause encephalitis in humans and horses, but there are no therapeutics for treatment. To date, compounds reported as anti-VEEV or anti-alphavirus inhibitors have shown moderate activity. To discover new classes of anti-VEEV inhibitors with novel viral targets, we used a high-throughput screen based on the measurement of cell protection from live VEEV TC-83-induced cytopathic effect to screen a 340,000 compound library. Of those, we identified five novel anti-VEEV compounds and chose a quinazolinone compound, CID15997213 (IC50 = 0.84 µM), for further characterization. The antiviral effect of CID15997213 was alphavirus-specific, inhibiting VEEV and Western equine encephalitis virus, but not Eastern equine encephalitis virus. In vitro assays confirmed inhibition of viral RNA, protein, and progeny synthesis. No antiviral activity was detected against a select group of RNA viruses. We found mutations conferring the resistance to the compound in the N-terminal domain of nsP2 and confirmed the target residues using a reverse genetic approach. Time of addition studies showed that the compound inhibits the middle stage of replication when viral genome replication is most active. In mice, the compound showed complete protection from lethal VEEV disease at 50 mg/kg/day. Collectively, these results reveal a potent anti-VEEV compound that uniquely targets the viral nsP2 N-terminal domain. While the function of nsP2 has yet to be characterized, our studies suggest that the protein might play a critical role in viral replication, and further, may represent an innovative opportunity to develop therapeutic interventions for alphavirus infection.

  4. Bioinformatics for microbial genotyping of equine encephalitis viruses, orthopoxviruses, and hantaviruses.

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    Gardner, Shea N; Jaing, Crystal J

    2013-10-01

    Microbial genotyping is essential for forensic discrimination of pathogen strains, tracing epidemics, and understanding evolutionary processes. Phylogenetic analyses were performed and genotyping assays designed for five viral species complexes or genera: Western, Eastern, and Venezuelan equine encephalitis viruses, hantavirus segments L, M, and S, and orthopoxviruses. For each group, sequence alignments and phylogenetic trees were built. PCR signatures composed of primer pairs or TaqMan™ triplets were designed and mapped to nodes of the trees for sub-type or strain specific PCR-based identification. In addition, single nucleotide polymorphisms (SNPs) were identified and mapped to trees, and SNP microarray probes were designed to enable highly multiplexed genotyping of an unsequenced sample by hybridization. SNP-based trees corresponded well with MSA trees. Near-perfect isolate resolution was possible for all viruses analyzed computationally using either SNPs or PCR signatures. More tree nodes were represented by SNP loci than by PCR signatures, as PCR signatures often represented subsets of strains not corresponding to a branch. However, while PCR genotyping is possible, the number of PCR signatures needed to characterize an unknown can be very large. SNP microarrays are a suitable alternative, as arrays enable highly multiplexed, high resolution genotyping of an unknown in a single hybridization assay. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

  5. Role of adhesion molecules and inflammation in Venezuelan equine encephalitis virus infected mouse brain

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    Honnold Shelley P

    2011-04-01

    Full Text Available Abstract Background Neuroinvasion of Venezuelan equine encephalitis virus (VEEV and subsequent initiation of inflammation in the brain plays a crucial role in the outcome of VEEV infection in mice. Adhesion molecules expressed on microvascular endothelial cells in the brain have been implicated in the modulation of the blood brain barrier (BBB and inflammation in brain but their role in VEEV pathogenesis is not very well understood. In this study, we evaluated the expression of extracellular matrix and adhesion molecules genes in the brain of VEEV infected mice. Findings Several cell to cell adhesion molecules and extracellular matrix protein genes such as ICAM-1, VCAM-1, CD44, Cadherins, integrins, MMPs and Timp1 were differentially regulated post-VEEV infection. ICAM-1 knock-out (IKO mice infected with VEEV had markedly reduced inflammation in the brain and demonstrated a delay in the onset of clinical symptoms of disease. A differential regulation of inflammatory genes was observed in the IKO mice brain compared to their WT counterparts. Conclusions These results improve our present understanding of VEEV induced inflammation in mouse brain.

  6. Venezuelan equine encephalitis replicon particles can induce rapid protection against foot-and-mouth disease virus.

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    Diaz-San Segundo, Fayna; Dias, Camila C A; Moraes, Mauro P; Weiss, Marcelo; Perez-Martin, Eva; Owens, Gary; Custer, Max; Kamrud, Kurt; de los Santos, Teresa; Grubman, Marvin J

    2013-05-01

    We have previously shown that delivery of the porcine type I interferon gene (poIFN-α/β) with a replication-defective human adenovirus vector (adenovirus 5 [Ad5]) can sterilely protect swine challenged with foot-and-mouth disease virus (FMDV) 1 day later. However, the need of relatively high doses of Ad5 limits the applicability of such a control strategy in the livestock industry. Venezuelan equine encephalitis virus (VEE) empty replicon particles (VRPs) can induce rapid protection of mice against either homologous or, in some cases, heterologous virus challenge. As an alternative approach to induce rapid protection against FMDV, we have examined the ability of VRPs containing either the gene for green fluorescent protein (VRP-GFP) or poIFN-α (VRP-poIFN-α) to block FMDV replication in vitro and in vivo. Pretreatment of swine or bovine cell lines with either VRP significantly inhibited subsequent infection with FMDV as early as 6 h after treatment and for at least 120 h posttreatment. Furthermore, mice pretreated with either 10(7) or 10(8) infectious units of VRP-GFP and challenged with a lethal dose of FMDV 24 h later were protected from death. Protection was induced as early as 6 h after treatment and lasted for at least 48 h and correlated with induction of an antiviral response and production of IFN-α. By 6 h after treatment several genes were upregulated, and the number of genes and the level of induction increased at 24 h. Finally, we demonstrated that the chemokine IP-10, which is induced by IFN-α and VRP-GFP, is directly involved in protection against FMDV.

  7. The first outbreak of eastern equine encephalitis in Vermont: outbreak description and phylogenetic relationships of the virus isolate.

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    Kali D Saxton-Shaw

    Full Text Available The first known outbreak of eastern equine encephalitis (EEE in Vermont occurred on an emu farm in Rutland County in 2011. The first isolation of EEE virus (EEEV in Vermont (VT11 was during this outbreak. Phylogenetic analysis revealed that VT11 was most closely related to FL01, a strain from Florida isolated in 2001, which is both geographically and temporally distinct from VT11. EEEV RNA was not detected in any of the 3,905 mosquito specimens tested, and the specific vectors associated with this outbreak are undetermined.

  8. Acute infection with venezuelan equine encephalitis virus replicon particles catalyzes a systemic antiviral state and protects from lethal virus challenge.

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    Konopka, Jennifer L; Thompson, Joseph M; Whitmore, Alan C; Webb, Drue L; Johnston, Robert E

    2009-12-01

    The host innate immune response provides a critical first line of defense against invading pathogens, inducing an antiviral state to impede the spread of infection. While numerous studies have documented antiviral responses within actively infected tissues, few have described the earliest innate response induced systemically by infection. Here, utilizing Venezuelan equine encephalitis virus (VEE) replicon particles (VRP) to limit infection to the initially infected cells in vivo, a rapid activation of the antiviral response was demonstrated not only within the murine draining lymph node, where replication was confined, but also within distal tissues. In the liver and brain, expression of interferon-stimulated genes was detected by 1 to 3 h following VRP footpad inoculation, reaching peak expression of >100-fold over that in mock-infected animals. Moreover, mice receiving a VRP footpad inoculation 6, 12, or 24 h prior to an otherwise lethal VEE footpad challenge were completely protected from death, including a drastic reduction in challenge virus titers. VRP pretreatment also provided protection from intranasal VEE challenge and extended the average survival time following intracranial challenge. Signaling through the interferon receptor was necessary for antiviral gene induction and protection from VEE challenge. However, VRP pretreatment failed to protect mice from a heterologous, lethal challenge with vesicular stomatitis virus, yet conferred protection following challenge with influenza virus. Collectively, these results document a rapid modulation of the host innate response within hours of infection, capable of rapidly alerting the entire animal to pathogen invasion and leading to protection from viral disease.

  9. Induction of neutralizing antibodies to Hendra and Nipah glycoproteins using a Venezuelan equine encephalitis virus in vivo expression system.

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    Defang, Gabriel N; Khetawat, Dimple; Broder, Christopher C; Quinnan, Gerald V

    2010-12-16

    The emergence of Hendra Virus (HeV) and Nipah Virus (NiV) which can cause fatal infections in both animals and humans has triggered a search for an effective vaccine. Here, we have explored the potential for generating an effective humoral immune response to these zoonotic pathogens using an alphavirus-based vaccine platform. Groups of mice were immunized with Venezuelan equine encephalitis virus replicon particles (VRPs) encoding the attachment or fusion glycoproteins of either HeV or NiV. We demonstrate the induction of highly potent cross-reactive neutralizing antibodies to both viruses using this approach. Preliminary study suggested early enhancement in the antibody response with use of a modified version of VRP. Overall, these data suggest that the use of an alphavirus-derived vaccine platform might serve as a viable approach for the development of an effective vaccine against the henipaviruses. Published by Elsevier Ltd.

  10. Structure and Immunogenicity of Alternative Forms of the Simian Immunodeficiency Virus Gag Protein Expressed Using Venezuelan Equine Encephalitis Virus Replicon Particles

    OpenAIRE

    Cecil, Chad; West, Ande; Collier, Martha; Jurgens, Christy; Madden, Victoria; Whitmore, Alan; Johnston, Robert; Moore, Dominic T.; Swanstrom, Ronald; Davis, Nancy L.

    2007-01-01

    Venezuelan equine encephalitis virus replicon particles (VRP) were engineered to express different forms of SIV Gag to compare expression in vitro, formation of intra- and extracellular structures and induction of humoral and cellular immunity in mice. The three forms examined were full-length myristylated SIV Gag (Gagmyr+), full-length Gag lacking the myristylation signal (Gagmyr-), or a truncated form of Gagmyr- comprising only the matrix and capsid domains (MA/CA). Comparison of VRP-infect...

  11. Humoral, mucosal, and cellular immunity in response to a human immunodeficiency virus type 1 immunogen expressed by a Venezuelan equine encephalitis virus vaccine vector.

    OpenAIRE

    Caley, I J; Betts, M R; Irlbeck, D M; Davis, N L; Swanstrom, R; Frelinger, J A; Johnston, R E

    1997-01-01

    A molecularly cloned attenuated strain of Venezuelan equine encephalitis virus (VEE) has been genetically configured as a replication-competent vaccine vector for the expression of heterologous viral proteins (N. L. Davis, K. W. Brown, and R. E. Johnston, J. Virol. 70:3781-3787, 1996). The matrix/capsid (MA/CA) coding domain of human immunodeficiency virus type 1 (HIV-1) was cloned into the VEE vector to determine the ability of a VEE vector to stimulate an anti-HIV immune response in mice. T...

  12. Cotton rats and house sparrows as hosts for North and South American strains of eastern equine encephalitis virus.

    Science.gov (United States)

    Arrigo, Nicole C; Adams, A Paige; Watts, Douglas M; Newman, Patrick C; Weaver, Scott C

    2010-09-01

    Eastern equine encephalitis virus (EEEV; family Togaviridae, genus Alphavirus) is an arbovirus that causes severe disease in humans in North America and in equids throughout the Americas. The enzootic transmission cycle of EEEV in North America involves passerine birds and the ornithophilic mosquito vector, Culiseta melanura, in freshwater swamp habitats. However, the ecology of EEEV in South America is not well understood. Culex (Melanoconion) spp. mosquitoes are considered the principal vectors in Central and South America; however, a primary vertebrate host for EEEV in South America has not yet been identified. Therefore, to further assess the reservoir host potential of wild rodents and wild birds, we compared the infection dynamics of North American and South American EEEV in cotton rats (Sigmodon hispidus) and house sparrows (Passer domesticus). Our findings suggested that each species has the potential to serve as amplification hosts for North and South America EEEVs.

  13. Novel inhibitors targeting Venezuelan equine encephalitis virus capsid protein identified using In Silico Structure-Based-Drug-Design.

    Science.gov (United States)

    Shechter, Sharon; Thomas, David R; Lundberg, Lindsay; Pinkham, Chelsea; Lin, Shih-Chao; Wagstaff, Kylie M; Debono, Aaron; Kehn-Hall, Kylene; Jans, David A

    2017-12-18

    Therapeutics are currently unavailable for Venezuelan equine encephalitis virus (VEEV), which elicits flu-like symptoms and encephalitis in humans, with an estimated 14% of cases resulting in neurological disease. Here we identify anti-VEEV agents using in silico structure-based-drug-design (SBDD) for the first time, characterising inhibitors that block recognition of VEEV capsid protein (C) by the host importin (IMP) α/β1 nuclear transport proteins. From an initial screen of 1.5 million compounds, followed by in silico refinement and screening for biological activity in vitro, we identified 21 hit compounds which inhibited IMPα/β1:C binding with IC50s as low as 5 µM. Four compounds were found to inhibit nuclear import of C in transfected cells, with one able to reduce VEEV replication at µM concentration, concomitant with reduced C nuclear accumulation in infected cells. Further, this compound was inactive against a mutant VEEV that lacks high affinity IMPα/β1:C interaction, supporting the mode of its antiviral action to be through inhibiting C nuclear localization. This successful application of SBDD paves the way for lead optimization for VEEV antivirals, and is an exciting prospect to identify inhibitors for the many other viral pathogens of significance that require IMPα/β1 in their infectious cycle.

  14. Venezuelan equine encephalitis virus replicon particle vaccine protects nonhuman primates from intramuscular and aerosol challenge with ebolavirus.

    Science.gov (United States)

    Herbert, Andrew S; Kuehne, Ana I; Barth, James F; Ortiz, Ramon A; Nichols, Donald K; Zak, Samantha E; Stonier, Spencer W; Muhammad, Majidat A; Bakken, Russell R; Prugar, Laura I; Olinger, Gene G; Groebner, Jennifer L; Lee, John S; Pratt, William D; Custer, Max; Kamrud, Kurt I; Smith, Jonathan F; Hart, Mary Kate; Dye, John M

    2013-05-01

    There are no vaccines or therapeutics currently approved for the prevention or treatment of ebolavirus infection. Previously, a replicon vaccine based on Venezuelan equine encephalitis virus (VEEV) demonstrated protective efficacy against Marburg virus in nonhuman primates. Here, we report the protective efficacy of Sudan virus (SUDV)- and Ebola virus (EBOV)-specific VEEV replicon particle (VRP) vaccines in nonhuman primates. VRP vaccines were developed to express the glycoprotein (GP) of either SUDV or EBOV. A single intramuscular vaccination of cynomolgus macaques with VRP expressing SUDV GP provided complete protection against intramuscular challenge with SUDV. Vaccination against SUDV and subsequent survival of SUDV challenge did not fully protect cynomolgus macaques against intramuscular EBOV back-challenge. However, a single simultaneous intramuscular vaccination with VRP expressing SUDV GP combined with VRP expressing EBOV GP did provide complete protection against intramuscular challenge with either SUDV or EBOV in cynomolgus macaques. Finally, intramuscular vaccination with VRP expressing SUDV GP completely protected cynomolgus macaques when challenged with aerosolized SUDV, although complete protection against aerosol challenge required two vaccinations with this vaccine.

  15. Co-delivery of antigen and IL-12 by Venezuelan equine encephalitis virus replicon particles enhances antigen-specific immune responses and anti-tumor effects

    OpenAIRE

    Osada, Takuya; Berglund, Peter; Morse, Michael A.; Hubby, Bolyn; Lewis, Whitney; Niedzwiecki, Donna; Hobeika, Amy; Burnett, Bruce; Devi, Gayathri R.; Clay, Timothy M.; Smith, Jonathan; Lyerly, H. Kim

    2012-01-01

    We recently demonstrated that Venezuelan equine encephalitis (VEE) virus-based replicon particles (VRP) encoding tumor antigens could break tolerance in the immunomodulatory environment of advanced cancer. We hypothesized that local injection of VRP expressing Interleukin-12 (IL-12) at the site of injections of VRP-based cancer vaccines would enhance the tumor-antigen-specific T cell and antibody responses and anti-tumor efficacy. Mice were immunized with VRP encoding the human tumor-associat...

  16. Vector-Host Interactions of Culiseta melanura in a Focus of Eastern Equine Encephalitis Virus Activity in Southeastern Virginia.

    Directory of Open Access Journals (Sweden)

    Goudarz Molaei

    Full Text Available Eastern equine encephalitis virus (EEEV causes a highly pathogenic mosquito-borne zoonosis that is responsible for sporadic outbreaks of severe illness in humans and equines in the eastern USA. Culiseta (Cs. melanura is the primary vector of EEEV in most geographic regions but its feeding patterns on specific avian and mammalian hosts are largely unknown in the mid-Atlantic region. The objectives of our study were to: 1 identify avian hosts of Cs. melanura and evaluate their potential role in enzootic amplification of EEEV, 2 assess spatial and temporal patterns of virus activity during a season of intense virus transmission, and 3 investigate the potential role of Cs. melanura in epidemic/epizootic transmission of EEEV to humans and equines. Accordingly, we collected mosquitoes at 55 sites in Suffolk, Virginia in 2013, and identified the source of blood meals in engorged mosquitoes by nucleotide sequencing PCR products of the mitochondrial cytochrome b gene. We also examined field-collected mosquitoes for evidence of infection with EEEV using Vector Test, cell culture, and PCR. Analysis of 188 engorged Cs. melanura sampled from April through October 2013 indicated that 95.2%, 4.3%, and 0.5% obtained blood meals from avian, mammalian, and reptilian hosts, respectively. American Robin was the most frequently identified host for Cs. melanura (42.6% of blood meals followed by Northern Cardinal (16.0%, European Starling (11.2%, Carolina Wren (4.3%, and Common Grackle (4.3%. EEEV was detected in 106 mosquito pools of Cs. melanura, and the number of virus positive pools peaked in late July with 22 positive pools and a Maximum Likelihood Estimation (MLE infection rate of 4.46 per 1,000 mosquitoes. Our findings highlight the importance of Cs. melanura as a regional EEEV vector based on frequent feeding on virus-competent bird species. A small proportion of blood meals acquired from mammalian hosts suggests the possibility that this species may

  17. Development of a novel monoclonal antibody with reactivity to a wide range of Venezuelan equine encephalitis virus strains

    Directory of Open Access Journals (Sweden)

    Phelps Amanda L

    2009-11-01

    Full Text Available Abstract Background There is currently a requirement for antiviral therapies capable of protecting against infection with Venezuelan equine encephalitis virus (VEEV, as a licensed vaccine is not available for general human use. Monoclonal antibodies are increasingly being developed as therapeutics and are potential treatments for VEEV as they have been shown to be protective in the mouse model of disease. However, to be truly effective, the antibody should recognise multiple strains of VEEV and broadly reactive monoclonal antibodies are rarely and only coincidentally isolated using classical hybridoma technology. Results In this work, methods were developed to reliably derive broadly reactive murine antibodies. A phage library was created that expressed single chain variable fragments (scFv isolated from mice immunised with multiple strains of VEEV. A broadly reactive scFv was identified and incorporated into a murine IgG2a framework. This novel antibody retained the broad reactivity exhibited by the scFv but did not possess virus neutralising activity. However, the antibody was still able to protect mice against VEEV disease induced by strain TrD when administered 24 h prior to challenge. Conclusion A monoclonal antibody possessing reactivity to a wide range of VEEV strains may be of benefit as a generic antiviral therapy. However, humanisation of the murine antibody will be required before it can be tested in humans. Crown Copyright © 2009

  18. Vector competence of eastern and western forms of Psorophora columbiae (Diptera: Culicidae) mosquitoes for enzootic and epizootic Venezuelan equine encephalitis virus.

    Science.gov (United States)

    Moncayo, Abelardo C; Lanzaro, Gregory; Kang, Wenli; Orozco, Arnoldo; Ulloa, Armando; Arredondo-Jiménez, Juan; Weaver, Scott C

    2008-03-01

    Venezuelan equine encephalitis virus (VEEV) continues to circulate enzootically in Mexico with the potential to re-emerge and cause disease in equines and humans in North America. We infected two geographically distinct mosquito populations of eastern Psorophora columbiae form columbiae (Chiapas, Mexico and Texas, United States) and one mosquito population of western Psorophora columbiae form toltecum (California, United States) with epizootic and enzootic IE VEEV and epizootic IAB VEEV. We detected no differences between epizootic and enzootic IE viruses in their ability to infect any of the mosquito populations analyzed, which suggested that neither species selects for epizootic IE viruses. Psorophora columbiae f. columbiae (Texas) were significantly less susceptible to infection by epizootic IE than Ps. columbiae f. columbiae (Mexico). Psorophora columbiae f. toltecum populations were more susceptible than Ps. columbiae f. columbiae populations to epizootic IE and IAB viruses.

  19. A humanised murine monoclonal antibody protects mice from Venezuelan equine encephalitis virus, Everglades virus and Mucambo virus when administered up to 48 h after airborne challenge

    Energy Technology Data Exchange (ETDEWEB)

    O' Brien, Lyn M., E-mail: lmobrien@dstl.gov.uk; Goodchild, Sarah A.; Phillpotts, Robert J.; Perkins, Stuart D.

    2012-05-10

    Currently there are no licensed antiviral treatments for the Alphaviruses Venezuelan equine encephalitis virus (VEEV), Everglades virus and Mucambo virus. We previously developed a humanised version of the mouse monoclonal antibody 1A3B-7 (Hu1A3B-7) which exhibited a wide range of reactivity in vitro and was able to protect mice from infection with VEEV. Continued work with the humanised antibody has now demonstrated that it has the potential to be a new human therapeutic. Hu1A3B-7 successfully protected mice from infection with multiple Alphaviruses. The effectiveness of the humanisation process was determined by assessing proliferation responses in human T-cells to peptides derived from the murine and humanised versions of the V{sub H} and V{sub L} domains. This analysis showed that the number of human T-cell epitopes within the humanised antibody had been substantially reduced, indicating that Hu1A3B-7 may have reduced immunogenicity in vivo.

  20. Characterizing areas of potential human exposure to eastern equine encephalitis virus using serological and clinical data from horses.

    Science.gov (United States)

    Rocheleau, J-P; Arsenault, J; Ogden, N H; Lindsay, L R; Drebot, M; Michel, P

    2017-03-01

    Eastern equine encephalitis (EEE) is a rare but severe emerging vector-borne disease affecting human and animal populations in the northeastern United States where it is endemic. Key knowledge gaps remain about the epidemiology of EEE virus (EEEV) in areas where its emergence has more recently been reported. In Eastern Canada, viral activity has been recorded in mosquitoes and horses throughout the 2000s but cases of EEEV in humans have not been reported so far. This study was designed to provide an assessment of possible EEEV human exposure by modelling environmental risk factors for EEEV in horses, identifying high-risk environments and mapping risk in the province of Quebec, Canada. According to logistic models, being located near wooded swamps was a risk factor for seropositivity or disease in horses [odds ratio (OR) 4·15, 95% confidence interval (CI) 1·16-14·8) whereas being located on agricultural lands was identified as protective (OR 0·75, 95% CI 0·62-0·92). A better understanding of the environmental risk of exposure to EEEV in Canada provides veterinary and public health officials with enhanced means to more effectively monitor the emergence of this public health risk and design targeted surveillance and preventive measures.

  1. Circulation of Eastern equine encephalitis, Western equine encephalitis, Ilhéus, Maguari and Tacaiuma viruses in equines of the Brazilian Pantanal, South America Circulação dos virus das encefalites equina do Leste e Oeste, Ilhéus, Maguari e Tacaiuma em equinos da região do Pantanal brasileiro, América do Sul

    Directory of Open Access Journals (Sweden)

    Lygia Busch Iversson

    1993-08-01

    Full Text Available Neutralizing antibodies to EEE (6.7%, WEE (1.2%, ILH (26.6%, MAG (28.2% and TCM (15.7% viruses were found in sera of 432 equines of the Brazilian Pantanal, area where undiagnosed horse deaths are frequently observed. A 4-fold rise in CF titer to EEE virus was detected in acute and convalescent sera of an encephalitis horse sacrified in 1992. Antibodies to EEE, ILH, MAG and TCM viruses were detected in horses less than 2 years old indicating recent circulation of these viruses in the Pantanal. The evidence of recent equine encephalitis associated with rising CF titer to EEE warrants a more intensive study with attempts to isolate virus from horses with clinical manifestations of encephalitis.Em um inquérito sorológico realizado em 432 equinos da região do Pantanal, território brasileiro, foram detectados anticorpos neutralizantes para os vírus EEE (6,7%, WEE (1,2%, ILH (26,6%, MAG (28,2% e TCM (15,7%. Detectou-se também em um cavalo com um quadro clínico de encefalite um aumento de 4 vezes no título de anticorpos fixadores de complemento para EEE em soros coletados nas fases aguda e convalescente da doença. Cavalos com menos de 2 anos de idade apresentaram anticorpos neutralizantes para EEE, ILH, MAG e TCM, indicando circulação recente desses vírus no Pantanal. Os achados justificam intensificar esses estudos na região com tentativas de isolamento de vírus de animais apresentando manifestações clínicas de encefalite.

  2. Infected dendritic cells are sufficient to mediate the adjuvant activity generated by Venezuelan equine encephalitis virus replicon particles.

    Science.gov (United States)

    Tonkin, Daniel R; Whitmore, Alan; Johnston, Robert E; Barro, Mario

    2012-06-22

    Replicon particles derived from Venezuelan equine encephalitis virus (VEE) are infectious non-propagating particles which act as a safe and potent systemic, mucosal, and cellular adjuvant when delivered with antigen. VEE and VEE replicon particles (VRP) can target multiple cell types including dendritic cells (DCs). The role of these cell types in VRP adjuvant activity has not been previously evaluated, and for these studies we focused on the contribution of DCs to the response to VRP. By analysis of VRP targeting in the draining lymph node, we found that VRP induced rapid recruitment of TNF-secreting monocyte-derived inflammatory dendritic cells. VRP preferentially infected these inflammatory DCs as well as classical DCs and macrophages, with less efficient infection of other cell types. DC depletion suggested that the interaction of VRP with classical DCs was required for recruitment of inflammatory DCs, induction of high levels of many cytokines, and for stable transport of VRP to the draining lymph node. Additionally, in vitro-infected DCs enhanced antigen-specific responses by CD4 and CD8 T cells. By transfer of VRP-infected DCs into mice we showed that these DCs generated an inflammatory state in the draining lymph node similar to that achieved by VRP injection. Most importantly, VRP-infected DCs were sufficient to establish robust adjuvant activity in mice comparable to that produced by VRP injection. These findings indicate that VRP infect, recruit and activate both classical and inflammatory DCs, and those DCs become mediators of the VRP adjuvant activity. Published by Elsevier Ltd.

  3. Gene Expression Profiling of Nonhuman Primates Exposed to Aerosolized Venezuelan Equine Encephalitis Virus

    Science.gov (United States)

    2007-12-01

    autoimmune demyelinating disease in mice. J Neuroimmunol 95: 43–54. Muro S, Taha R, Tsicopoulos A, Olivenstein R, Tonnel AB, Christodoulopoulos P...Army Medical Research Institute of Infectious Diseases , Fort Detrick, Frederick, MD, USA; 2Virginia Bioinformatics Institute, Bioinformatics Facility...less frequently in humans, with neurological diseases appearing in 4–14% of the cases. VEE occurs in all age groups, and fatal encephalitis is more

  4. Whooping crane titers to eastern equine encephalitis vaccinations

    Science.gov (United States)

    Olsen, G.H.; Kolski, E.; Hatfield, J.S.; Docherty, D.E.; Chavez-Ramirez, Felipe

    2005-01-01

    In 1984 an epizootic of eastern equine encephalitis (EEE) virus killed 7 of 39 (18%) whooping cranes in captivity at the Patuxent Wildlife Research Center in Laurel, Maryland, USA. Since that time whooping cranes have been vaccinated with a human EEE vaccine. This vaccine was unavailable for several years, necessitating use of an equine vaccine in the cranes. This study compared the antibody titers measured for three years using the human vaccine with those measured for two years using the equine form. Whooping cranes developed similarly elevated titers in one year using the human vaccine and both years using the equine vaccine. However, in two years where the human vaccine was used, the whooping cranes developed significantly lower titers compared to other years.

  5. Live, Attenuated Venezuelan Equine Encephalitis Virus Vaccine (TC83) Causes Persistent Brain Infection in Mice with Non-functional αβ T-Cells

    Science.gov (United States)

    Taylor, Katherine; Kolokoltsova, Olga; Ronca, Shannon E.; Estes, Mark; Paessler, Slobodan

    2017-01-01

    Intranasal infection with vaccine strain of Venezuelan equine encephalitis virus (TC83) caused persistent viral infection in the brains of mice without functional αβ T-cells (αβ-TCR -/-). Remarkably, viral kinetics, host response gene transcripts and symptomatic disease are similar between αβ-TCR -/- and wild-type C57BL/6 (WT) mice during acute phase of infection [0–13 days post-infection (dpi)]. While WT mice clear infectious virus in the brain by 13 dpi, αβ-TCR -/- maintain infectious virus in the brain to 92 dpi. Persistent brain infection in αβ-TCR -/- correlated with inflammatory infiltrates and elevated cytokine protein levels in the brain at later time points. Persistent brain infection of αβ-TCR -/- mice provides a novel model to study prolonged alphaviral infection as well as the effects and biomarkers of long-term viral inflammation in the brain. PMID:28184218

  6. mRNA Capping by Venezuelan Equine Encephalitis Virus nsP1: Functional Characterization and Implications for Antiviral Research.

    Science.gov (United States)

    Li, Changqing; Guillén, Jaime; Rabah, Nadia; Blanjoie, Alexandre; Debart, Françoise; Vasseur, Jean-Jacques; Canard, Bruno; Decroly, Etienne; Coutard, Bruno

    2015-08-01

    Alphaviruses are known to possess a unique viral mRNA capping mechanism involving the viral nonstructural protein nsP1. This enzyme harbors methyltransferase (MTase) and nsP1 guanylylation (GT) activities catalyzing the transfer of the methyl group from S-adenosylmethionine (AdoMet) to the N7 position of a GTP molecule followed by the formation of an m(7)GMP-nsP1 adduct. Subsequent transfer of m(7)GMP onto the 5' end of the viral mRNA has not been demonstrated in vitro yet. Here we report the biochemical characterization of Venezuelan equine encephalitis virus (VEEV) nsP1. We have developed enzymatic assays uncoupling the different reactions steps catalyzed by nsP1. The MTase and GT reaction activities were followed using a nonhydrolyzable GTP (GIDP) substrate and an original Western blot assay using anti-m3G/m(7)G-cap monoclonal antibody, respectively. The GT reaction is stimulated by S-adenosyl-l-homocysteine (Ado-Hcy), the product of the preceding MTase reaction, and metallic ions. The covalent linking between nsP1 and m(7)GMP involves a phosphamide bond between the nucleotide and a histidine residue. Final guanylyltransfer onto RNA was observed for the first time with an alphavirus nsP1 using a 5'-diphosphate RNA oligonucleotide whose sequence corresponds to the 5' end of the viral genome. Alanine scanning mutagenesis of residues H37, H45, D63, E118, Y285, D354, R365, N369, and N375 revealed their respective roles in MT and GT reactions. Finally, the inhibitory effects of sinefungin, aurintricarboxylic acid (ATA), and ribavirin triphosphate on MTase and capping reactions were investigated, providing possible avenues for antiviral research. Emergence or reemergence of alphaviruses represents a serious health concern, and the elucidation of their replication mechanisms is a prerequisite for the development of specific inhibitors targeting viral enzymes. In particular, alphaviruses are able, through an original reaction sequence, to add to their mRNA a cap

  7. Virion polypeptide heterogeneity among virulent and avirulent strains of eastern equine encephalitis (EEE) virus.

    Science.gov (United States)

    Walder, R; Rosato, R R; Eddy, G A

    1981-01-01

    Comparative analysis of structural virion polypeptides of 24 selected EEE virus strains, representing North and South American types, was performed by one-dimensional discontinuous sodium dodecyl sulfate (SDS)-polyacrylamide-gel electrophoresis (PAGE). The structural proteins of different EEE virus isolates, resolved by this method, exhibited mol.wts. values in the range of 57-60 X 10(3) for (E-1), 51-54 X 10(3) for (E-2) and 35-38 X 10(3) daltons for the core (NP) nucleocapsid. The exception was the South American human lethal virus, TRVL-89287 strain, which was shown to possess only a single envelope glycoprotein. The high molecular weight envelope (E-1) glycoprotein species was absent or co-migrated adjacent to the smaller envelope (E-2) glycoprotein. Results indicated similarities in the core (NP) proteins, however greater variability in the envelope (E-/ and/or E-2) glycoproteins. Based on these variations seven distinct profiles could be observed among the EEE virus strain studied. The classification based on the patterns of structural polypeptides obtained by SDS-PAGE of these strains does not correlate well with any other previously reported in vitro characteristics (antigenic subtypes, HTP elution profiles) nor with the in vivo virulence markers.

  8. A Novel, Rapid Assay for Detection and Differentiation of Serotype-Specific Antibodies to Venezuelan Equine Encephalitis Complex Alphaviruses

    National Research Council Canada - National Science Library

    Wang, Eryu; Paessler, Slobodan; Smith, Darci R; Coffey, Lark L; Kang, Wenli; Estrada-Franco, Jose; Weaver, Scott C; Aguilar, Patricia V; Pfeffer, Martin; Olson, James

    2005-01-01

    ... of Venezuelan equine encephalitis (VEE) virus. Two monoclonal antibodies that differentially recognize epizootic versus enzootic VEE virus epitopes were used to measure the serotype-specific blocking abilities of antibodies in sera of naturally...

  9. Role of Cytokines and Neurotrophins in the Central Nervous System in Venezuelan Equine Encephalitis Virus Pathogenesis

    Science.gov (United States)

    2001-01-01

    for Guillain Barr Syndrome , an acute demyelinating inflammatory polyneuropathy. EAN is also suppressed by treatment with TGF-ß (29). The absence of...Schoneboom. 35 Guillain Barr Syndrome (GBS). GBS patients display elevated levels of IL-6 in their cerebrospinal fluid, but the significance of this...Deficiency Syndrome ALS Amylotrophic Lateral Scleropathy BDNF Brain derived neurotrophic factor BDV Borna Disease Virus CNTF Ciliary neurotrophic

  10. 1,5 iodonaphthyl Azide Inactivated V3526 Protects against Aerosol Challenge with Virulent Venezuelan Equine Encephalitis Virus.

    Science.gov (United States)

    2016-06-02

    Vero 76 cells were seeded at a density of 4 x 104 cells /well of a 96-well plate (Corning, VWR Cat #29443-050, Bridgeport, NJ) and incubated overnight...et al. Alpha-beta T cells provide protection against lethal encephalitis in the murine model of VEEV infection. Virology. 2007;367:307-23...diluted serum samples and incubated overnight at 4oC. Following incubation, sample+virus mixtures were transferred to a 96-well plate containing Vero

  11. Eastern equine encephalitis cases among horses in Brazil between 2005 and 2009.

    Science.gov (United States)

    de Novaes Oliveira, Rafael; Iamamoto, Keila; Silva, Maria Luana Cristiny Rodrigues; Achkar, Samira Maria; Castilho, Juliana Galera; Ono, Ekaterina Durymanova; Lobo, Renata Spinelli Vaz; Brandão, Paulo Eduardo; Carnieli, Pedro; Carrieri, Maria Luiza; Kotait, Ivanete; Macedo, Carla Isabel

    2014-10-01

    Eastern equine encephalitis is a viral zoonosis that exhibits complex distribution and epidemiology, and greater importance should be given to this disease by the public-health authorities. In Brazil, although eastern equine encephalitis virus (EEEV) has been identified in vectors and antibodies are sometimes detected in horses and humans, there have been no records of equine encephalitis in horses caused by this virus during the last 24 years. This study describes eighteen cases of eastern equine encephalomyelitis that occurred in six Brazilian states between 2005 and 2009. Viral RNA was identified using semi-nested RT-PCR to detect members of the genus Alphavirus, and by genetic sequencing. The gene encoding NSP1 was partially amplified, and after genetic sequencing, eighteen sequences were generated. All eighteen strains were classified as belonging to lineage III of American EEEV. These findings could be an indication of the importance of this virus in animal and human public health.

  12. Eastern equine encephalitis: an emerging arboviral disease threat, Maine, 2009.

    Science.gov (United States)

    Gibney, Katherine B; Robinson, Sara; Mutebi, John-Paul; Hoenig, Donald E; Bernier, Brian J; Webber, Lori; Lubelczyk, Charles; Nett, Randall J; Fischer, Marc

    2011-06-01

    Eastern equine encephalitis (EEE) is one of the most severe arboviral encephalitides in North America. Before 2009, limited nonhuman EEE virus activity had been reported in Maine, all from the southernmost area of the state. No human case has been reported in a Maine resident. We review all EEE virus activity reported to Maine Centers for Disease Control in 2009 and describe current testing practices for possible human EEE cases. In 2009, fatal cases of EEE were identified in 15 horses, 1 llama, and 3 flocks of pheasants in Maine, with activity extending into the central part of the state. Although no human EEE cases were identified, diagnostic testing practices of most meningitis and encephalitis cases were inadequate to exclude EEE. Work to better define the expanding range of EEE virus in Maine is warranted, along with education of healthcare providers regarding appropriate testing for this serious disease.

  13. Arbovirus investigations in Argentina, 1977-1980. III. Identification and characterization of viruses isolated, including new subtypes of western and Venezuelan equine encephalitis viruses and four new bunyaviruses (Las Maloyas, Resistencia, Barranqueras, and Antequera).

    Science.gov (United States)

    Calisher, C H; Monath, T P; Mitchell, C J; Sabattini, M S; Cropp, C B; Kerschner, J; Hunt, A R; Lazuick, J S

    1985-09-01

    Forty viruses isolated from mosquitoes between 1977 and 1980 in Argentina have been identified and characterized. Nineteen strains of VEE virus, identical by neutralization (N) tests, were shown by hemagglutination-inhibition tests with anti-E2 glycoprotein sera to represent a new subtype VI of the VEE complex. RNA oligonucleotide fingerprints of this virus were distinct from subtype I viruses. The virus was not lethal for English short-haired guinea pigs, indicating that it is probably not equine-virulent. Three strains of a member of the WEE virus complex were shown to differ by N tests in 1 direction from prototype WEE virus. The new WEE subtype was also found to be distinct by RNA oligonucleotide mapping. Its vector relationships indicate that it is an enzootic virus, and it has not been associated with equine disease. A new member of the Anopheles A serogroup was identified, shown to be most closely related to Lukuni and Col An 57389 viruses, and given the name Las Maloyas virus. A strain of Para virus (Bunyaviridae, Bunyavirus) was identified. Six isolates, representing 3 new viruses morphologically resembling bunyaviruses are described; the names Antequera, Barranqueras, and Resistencia are proposed for these agents, which were all isolated from Culex (Melanoconion) delpontei in Chaco Province. No serologic relationships between these viruses and other bunyaviruses were found. Since they are antigenically interrelated, they form a new (Antequera) serogroup. Eight Gamboa serogroup viruses and 2 strains of St. Louis encephalitis virus were also identified.

  14. St. Louis Encephalitis

    Science.gov (United States)

    ... Information Virus Transmission Epidemiology & Geographic Distribution Symptoms and Treatment Diagnosis Links & References Fact Sheet Other diseases transmitted by mosquitoes Chikungunya virus Dengue Eastern Equine Encephalitis Japanese Encephalitis La Crosse Encephalitis ...

  15. Natural variation in the heparan sulfate binding domain of the eastern equine encephalitis virus E2 glycoprotein alters interactions with cell surfaces and virulence in mice.

    Science.gov (United States)

    Gardner, Christina L; Choi-Nurvitadhi, Jo; Sun, Chengqun; Bayer, Avraham; Hritz, Jozef; Ryman, Kate D; Klimstra, William B

    2013-08-01

    Recently, we compared amino acid sequences of the E2 glycoprotein of natural North American eastern equine encephalitis virus (NA-EEEV) isolates and demonstrated that naturally circulating viruses interact with heparan sulfate (HS) and that this interaction contributes to the extreme neurovirulence of EEEV (C. L. Gardner, G. D. Ebel, K. D. Ryman, and W. B. Klimstra, Proc. Natl. Acad. Sci. U. S. A., 108:16026-16031, 2011). In the current study, we have examined the contribution to HS binding of each of three lysine residues in the E2 71-to-77 region that comprise the primary HS binding site of wild-type (WT) NA-EEEV viruses. We also report that the original sequence comparison identified five virus isolates, each with one of three amino acid differences in the E2 71-to-77 region, including mutations in residues critical for HS binding by the WT virus. The natural variant viruses, which possessed either a mutation from lysine to glutamine at E2 71, a mutation from lysine to threonine at E2 71, or a mutation from threonine to lysine at E2 72, exhibited altered interactions with heparan sulfate and cell surfaces and altered virulence in a mouse model of EEEV disease. An electrostatic map of the EEEV E1/E2 heterotrimer based upon the recent Chikungunya virus crystal structure (J. E. Voss, M. C. Vaney, S. Duquerroy, C. Vonrhein, C. Girard-Blanc, E. Crublet, A. Thompson, G. Bricogne, and F. A. Rey, Nature, 468:709-712, 2010) showed the HS binding site to be at the apical surface of E2, with variants affecting the electrochemical nature of the binding site. Together, these results suggest that natural variation in the EEEV HS binding domain may arise during EEEV sylvatic cycles and that this variation may influence receptor interaction and the severity of EEEV disease.

  16. Venezuelan equine Encephalitis virus capsid protein forms a tetrameric complex with CRM1 and importin alpha/beta that obstructs nuclear pore complex function.

    Science.gov (United States)

    Atasheva, Svetlana; Fish, Alexander; Fornerod, Maarten; Frolova, Elena I

    2010-05-01

    Development of the cellular antiviral response requires nuclear translocation of multiple transcription factors and activation of a wide variety of cellular genes. To counteract the antiviral response, several viruses have developed an efficient means of inhibiting nucleocytoplasmic traffic. In this study, we demonstrate that the pathogenic strain of Venezuelan equine encephalitis virus (VEEV) has developed a unique mechanism of nuclear import inhibition. Its capsid protein forms a tetrameric complex with the nuclear export receptor CRM1 and the nuclear import receptor importin alpha/beta. This unusual complex accumulates in the center channel of the nuclear pores and blocks nuclear import mediated by different karyopherins. The inhibitory function of VEEV capsid protein is determined by a short 39-amino-acid-long peptide that contains both nuclear import and supraphysiological nuclear export signals. Mutations in these signals or in the linker peptide attenuate or completely abolish capsid-specific inhibition of nuclear traffic. The less pathogenic VEEV strains contain a wide variety of mutations in this peptide that affect its inhibitory function in nuclear import. Thus, these mutations appear to be the determinants of this attenuated phenotype. This novel mechanism of inhibiting nuclear transport also shows that the nuclear pore complex is vulnerable to unusual cargo receptor complexes and sheds light on the importance of finely adjusted karyopherin-nucleoporin interactions for efficient cargo translocation.

  17. Epidemic Venezuelan Equine Encephalitis in La Guajira, Colombia, 1995

    National Research Council Canada - National Science Library

    F. Rivas; L. A. Diaz; V. M. Cardenas; E. Daza; L. Bruzon; A. Alcala; O. De la Hoz; F. M. Caceres; G. Aristizabal; J. W. Martinez; D. Revelo; F. De la Hoz; J. Boshell; T. Camacho; L. Calderon; V. A. Olano; L. I. Villarreal; D. Roselli; G. Alvarez; G. Ludwig; T. Tsai

    1997-01-01

    In 1995, the first Venezuelan equine encephalitis (VEE) outbreak in Colombia in 22 years caused an estimated 75,000 human cases, 3000 with neurologic complications and 300 fatal, in La Guajira State...

  18. Dynamics of Vector-Host Interactions in Avian Communities in Four Eastern Equine Encephalitis Virus Foci in the Northeastern U.S.

    Directory of Open Access Journals (Sweden)

    Goudarz Molaei

    2016-01-01

    Full Text Available Eastern equine encephalitis (EEE virus (Togaviridae, Alphavirus is a highly pathogenic mosquito-borne zoonosis that is responsible for occasional outbreaks of severe disease in humans and equines, resulting in high mortality and neurological impairment in most survivors. In the past, human disease outbreaks in the northeastern U.S. have occurred intermittently with no apparent pattern; however, during the last decade we have witnessed recurring annual emergence where EEE virus activity had been historically rare, and expansion into northern New England where the virus had been previously unknown. In the northeastern U.S., EEE virus is maintained in an enzootic cycle involving the ornithophagic mosquito, Culiseta melanura, and wild passerine (perching birds in freshwater hardwood swamps. However, the identity of key avian species that serve as principal virus reservoir and amplification hosts has not been established. The efficiency with which pathogen transmission occurs within an avian community is largely determined by the relative reservoir competence of each species and by ecological factors that influence contact rates between these avian hosts and mosquito vectors.Contacts between vector mosquitoes and potential avian hosts may be directly quantified by analyzing the blood meal contents of field-collected specimens. We used PCR-based molecular methods and direct sequencing of the mitochondrial cytochrome b gene for profiling of blood meals in Cs. melanura, in an effort to quantify its feeding behavior on specific vertebrate hosts, and to infer epidemiologic implications in four historic EEE virus foci in the northeastern U.S. Avian point count surveys were conducted to determine spatiotemporal host community composition. Of 1,127 blood meals successfully identified to species level, >99% of blood meals were from 65 avian hosts in 27 families and 11 orders, and only seven were from mammalian hosts representing three species. We developed an

  19. Identification of bloodmeals in Anopheles quadrimaculatus and Anopheles punctipennis from eastern equine encephalitis virus foci in northeastern U.S.A.

    Science.gov (United States)

    Molaei, G; Farajollahi, A; Armstrong, P M; Oliver, J; Howard, J J; Andreadis, T G

    2009-12-01

    The host-feeding patterns of Anopheles quadrimaculatus Say and Anopheles punctipennis (Say) were examined in order to evaluate their potential contributions to the transmission of eastern equine encephalitis virus (EEEv) and other arboviruses in the northeastern U.S.A. Engorged mosquitoes of the two species were collected from EEEv foci in central New York (NY) and throughout New Jersey (NJ), and their bloodmeals were identified using a polymerase chain reaction (PCR)-based assay and sequencing portions of the mitochondrial cytochrome b gene. Analysis of 131 An. quadrimaculatus and 107 An. punctipennis from NY revealed that 97.7% and 97.2%, respectively, had acquired blood solely from mammalian hosts. Similarly, examination of 288 An. quadrimaculatus and 127 An. punctipennis from NJ showed 100% and 96.0%, respectively, contained mammalian-derived bloodmeals. Mosquitoes containing mixed bloodmeals from both avian and mammalian hosts were detected in 1.6% of An. quadrimaculatus from NY, and 2.8% and 4.0% of An. punctipennis from NY and NJ, respectively. White-tailed deer (Odocoileus virginianus) constituted the most common vertebrate host for these anopheline mosquitoes, accounting for 85.8-97.7% of all bloodmeals identified. The predominance of white-tailed deer as a source of bloodmeals supports enzootic amplification of deer-associated arboviruses in this region, including Jamestown Canyon, Cache Valley and Potosi viruses. One horse- and two human-derived bloodmeals were also detected in An. quadrimaculatus collected in NJ. Limited avian-derived bloodmeals were detected from mourning dove (Zenaida macroura), sharp-shinned hawk (Accipiter striatus) and house finch (Carpodacus mexicanus), mostly in mixed bloodmeals. Occasional feeding on avian hosts suggests that these mosquitoes may participate as epizootic-epidemic bridge vectors of EEEv from viraemic birds to mammalian hosts of concern, including horses and humans. An isolate of EEEv was recovered from the head

  20. Mutation of Asn-475 in the Venezuelan Equine Encephalitis Virus nsP2 Cysteine Protease Leads to a Self-Inhibited State.

    Science.gov (United States)

    Compton, Jaimee R; Mickey, Matthew J; Hu, Xin; Marugan, Juan J; Legler, Patricia M

    2017-11-28

    The alphaviral nsP2 cysteine protease of the Venezuelan equine encephalitis virus (VEEV) is a validated antiviral drug target. Clan CN proteases contain a cysteine protease domain that is intimately packed with an S-adenosyl-l-methionine-dependent RNA methyltransferase (SAM MTase) domain. Within a cleft formed at the interface of these two domains, the peptide substrate is thought to bind. The nucleophilic cysteine can be found within a conserved motif, 475NVCWAK480, which differs from that of papain (22CGSCWAFS29). Mutation of the motif residue, N475, to alanine unexpectedly produced a self-inhibited state in which the N-terminal residues flipped into the substrate-binding cleft. Notably, the N-terminal segment was not hydrolyzed-consistent with a catalytically incompetent state. The N475A mutation resulted in a 70-fold decrease in kcat/Km. A side chain-substrate interaction was predicted by the structure; the S701A mutation led to a 17-fold increase in Km. An Asn at the n-2 position relative to the Cys was also found in the coronaviral papain-like proteases/deubiquitinases (PLpro) of the SARS and MERS viruses, and in several papain-like human ubiquitin specific proteases (USP). The large conformational change in the N475A variant suggests that Asn-475 plays an important role in stabilizing the N-terminal residues and in orienting the carbonyl during nucleophilic attack but does not directly hydrogen bond the oxyanion. The state trapped in crystallo is an unusual result of site-directed mutagenesis but reveals the role of this highly conserved Asn and identifies key substrate-binding contacts that may be exploited by peptide-like inhibitors.

  1. Eastern equine encephalitis in 9 South American camelids.

    Science.gov (United States)

    Nolen-Walston, Rose; Bedenice, Daniela; Rodriguez, Carlos; Rushton, Steven; Bright, Amy; Fecteau, Marie-Eve; Short, Diana; Majdalany, Ron; Tewari, Deepanker; Pedersen, Douglas; Kiupel, Matti; Maes, Roger; Del Piero, Fabio

    2007-01-01

    Eastern equine encephalitis (EEE) virus is a mosquito-borne togavirus (alphavirus) that causes severe (often fatal) encephalitis in many mammalian species, but it has not been reported previously in South American camelids. South American camelids can become naturally infected with EEE virus and show encephalitic signs similar to those observed in other affected species. Nine cases (8 alpacas and 1 llama, aged 3.5 weeks to 12 years) were identified; 4 of 9 were 510 weeks old. All cases were from the East Coast of the United States and presented in late summer and fall. A retrospective study was performed to include confirmed cases of EEE in camelids in North America before 2006. Eight of nine (89%) camelids died or were euthanized in extremis, with the mean time to death of 2 days. Clinical signs were consistent with encephalitis and included fever, lethargy, ataxia, seizures, recumbency, torticollis, opisthotonus, and vestibular signs. No consistent hematologic abnormalities were identified, and cerebrospinal fluid contained an increased protein concentration in the single camelid analyzed. No successful therapy was identified. EEE was confirmed by alphavirus detection by using immunohistochemistry (IHC) and polymerase chain reaction (PCR) in the central nervous system (CNS) and by serology. Findings included polioencephalitis with lymphocytic perivascular cuffing; neutrophil infiltration; gliosis; neuron satellitosis; necrosis; and edema, with intracytoplasmic alphavirus within neurons and glial cells. No virus was detected in extraneural tissues. In endemic areas, EEE should be considered a differential diagnosis for young and adult camelids with CNS disease. Brain histopathology with indirect IHC or PCR is diagnostic.

  2. Co-delivery of antigen and IL-12 by Venezuelan equine encephalitis virus replicon particles enhances antigen-specific immune responses and anti-tumor effects

    Science.gov (United States)

    Osada, Takuya; Berglund, Peter; Morse, Michael A.; Hubby, Bolyn; Lewis, Whitney; Niedzwiecki, Donna; Hobeika, Amy; Burnett, Bruce; Devi, Gayathri R.; Clay, Timothy M.; Smith, Jonathan; Lyerly, H. Kim

    2013-01-01

    We recently demonstrated that Venezuelan equine encephalitis (VEE) virus-based replicon particles (VRP) encoding tumor antigens could break tolerance in the immunomodulatory environment of advanced cancer. We hypothesized that local injection of VRP expressing Interleukin-12 (IL-12) at the site of injections of VRP-based cancer vaccines would enhance the tumor-antigen-specific T cell and antibody responses and anti-tumor efficacy. Mice were immunized with VRP encoding the human tumor-associated antigen, carcinoembryonic antigen (CEA) (VRP-CEA(6D)) and VRP-IL-12 was also administered at the same site or at a distant location. CEA-specific T cell and antibody responses were measured. To determine antitumor activity, mice were implanted with MC38-CEA-2 cells and immunized with VRP-CEA with and without VRP-IL-12 and tumor growth and mouse survival were measured. VRP-IL-12 greatly enhanced CEA-specific T cell and antibody responses when combined with VRP-CEA(6D) vaccination. VRP IL-12 was superior to IL-12 protein at enhancing immune responses. Vaccination with VRP-CEA(6D) plus VRP-IL-12 was superior to VRP-CEA(6D) or VRP-IL-12 alone in inducing anti-tumor activity and prolonging survival in tumor-bearing mice. Importantly, local injection of VRP-IL-12 at the VRP-CEA(6D) injection site provided more potent activation of CEA-specific immune responses than VRP-IL-12 injected at a distant site from the VRP-CEA injections. Together, this study shows that VRP-IL-12 enhances vaccination with VRP-CEA(6D) and was more effective at activating CEA-specific T cell responses when locally expressed at the vaccine site. Clinical trials evaluating the adjuvant effect of VRP-IL-12 at enhancing the immunogenicity of cancer vaccines are warranted. PMID:22488274

  3. Co-delivery of antigen and IL-12 by Venezuelan equine encephalitis virus replicon particles enhances antigen-specific immune responses and antitumor effects.

    Science.gov (United States)

    Osada, Takuya; Berglund, Peter; Morse, Michael A; Hubby, Bolyn; Lewis, Whitney; Niedzwiecki, Donna; Yang, Xiao Yi; Hobeika, Amy; Burnett, Bruce; Devi, Gayathri R; Clay, Timothy M; Smith, Jonathan; Kim Lyerly, H

    2012-11-01

    We recently demonstrated that Venezuelan equine encephalitis virus-based replicon particle (VRPs) encoding tumor antigens could break tolerance in the immunomodulatory environment of advanced cancer. We hypothesized that local injection of VRP-expressing interleukin-12 (IL-12) at the site of injections of VRP-based cancer vaccines would enhance the tumor-antigen-specific T cell and antibody responses and antitumor efficacy. Mice were immunized with VRP encoding the human tumor-associated antigen, carcinoembryonic antigen (CEA) (VRP-CEA(6D)), and VRP-IL-12 was also administered at the same site or at a distant location. CEA-specific T cell and antibody responses were measured. To determine antitumor activity, mice were implanted with MC38-CEA-2 cells and immunized with VRP-CEA with and without VRP-IL-12, and tumor growth and mouse survival were measured. VRP-IL-12 greatly enhanced CEA-specific T cell and antibody responses when combined with VRP-CEA(6D) vaccination. VRP-IL-12 was superior to IL-12 protein at enhancing immune responses. Vaccination with VRP-CEA(6D) plus VRP-IL-12 was superior to VRP-CEA(6D) or VRP-IL-12 alone in inducing antitumor activity and prolonging survival in tumor-bearing mice. Importantly, local injection of VRP-IL-12 at the VRP-CEA(6D) injection site provided more potent activation of CEA-specific immune responses than that of VRP-IL-12 injected at a distant site from the VRP-CEA injections. Together, this study shows that VRP-IL-12 enhances vaccination with VRP-CEA(6D) and was more effective at activating CEA-specific T cell responses when locally expressed at the vaccine site. Clinical trials evaluating the adjuvant effect of VRP-IL-12 at enhancing the immunogenicity of cancer vaccines are warranted.

  4. Western equine encephalitis with rapid onset of parkinsonism.

    Science.gov (United States)

    Schultz, D R; Barthal, J S; Garrett, G

    1977-11-01

    A patient with confirmed western equine encephalitis had the rapid onset of postencephalitic parkinsonian sequelae. This observation corroborates similar previous but rare reports. Response to therapy with levodopa, dopa decarboxylase inhibitor, and trihexyphenidyl was dramatic. However, remission maintained for 12 months without medication suggests that the parkinsonism would have remitted spontaneously. In either case, this has not previously been reported with the western equine togavirus.

  5. An Immunoinformatics-Derived DNA Vaccine Encoding Human Class 2 T Cell Epitopes of Ebola Virus, Sudan Virus, and Venezuelan Equine Encephalitis Virus is Immunogenic in HLA Transgenic Mice

    Science.gov (United States)

    2017-04-07

    1 An immunoinformatics-derived DNA vaccine encoding human Class II T cell epitopes of 1 Ebola virus, Sudan virus, and Venezuelan equine...connie.s.schmaljohn.civ@mail.mil 13 14 Keywords: genome-derived vaccine, epitope-based vaccine, DNA vaccine, peptide vaccine, T 15 cell epitope, Ebola virus, EBOV...for biodefense. We previously developed and 53 tested DNA vaccines expressing the envelope glycoproteins of these viruses in mice and 54 nonhuman

  6. A novel cell-based assay to measure activity of Venezuelan equine encephalitis virus nsP2 protease

    Energy Technology Data Exchange (ETDEWEB)

    Campos-Gomez, Javier; Ahmad, Fahim; Rodriguez, Efrain; Saeed, Mohammad F., E-mail: saeed@southernresearch.org

    2016-09-15

    The encephalitic alphaviruses encode nsP2 protease (nsP2pro), which because of its vital role in virus replication, represents an attractive target for therapeutic intervention. To facilitate the discovery of nsP2 inhibitors we have developed a novel assay for quantitative measurement of nsP2pro activity in a cell-based format. The assay is based on a substrate fusion protein consisting of eGFP and Gaussia luciferase (Gluc) linked together by a small peptide containing a VEEV nsp2pro cleavage sequence. The expression of the substrate protein in cells along with recombinant nsP2pro results in cleavage of the substrate protein resulting in extracellular release of free Gluc. The Gluc activity in supernatants corresponds to intracellular nsP2pro-mediated substrate cleavage; thus, providing a simple and convenient way to quantify nsP2pro activity. Here, we demonstrate potential utility of the assay in identification of nsP2pro inhibitors, as well as in investigations related to molecular characterization of nsP2pro. - Highlights: • A novel cell-based assay to measure VEEV nsP2 protease activity was developed. • Assay utility was demonstrated for antiviral screening. • .The assay also proved to be useful in basic mechanistic studies of nsP2 protease.

  7. Equine Immunoglobulin and Equine Neutralizing F(ab')₂ Protect Mice from West Nile Virus Infection.

    Science.gov (United States)

    Cui, Jiannan; Zhao, Yongkun; Wang, Hualei; Qiu, Boning; Cao, Zengguo; Li, Qian; Zhang, Yanbo; Yan, Feihu; Jin, Hongli; Wang, Tiecheng; Sun, Weiyang; Feng, Na; Gao, Yuwei; Sun, Jing; Wang, Yanqun; Perlman, Stanley; Zhao, Jincun; Yang, Songtao; Xia, Xianzhu

    2016-12-18

    West Nile virus (WNV) is prevalent in Africa, Europe, the Middle East, West Asia, and North America, and causes epidemic encephalitis. To date, no effective therapy for WNV infection has been developed; therefore, there is urgent need to find an efficient method to prevent WNV disease. In this study, we prepared and evaluated the protective efficacy of immune serum IgG and pepsin-digested F(ab')₂ fragments from horses immunized with the WNV virus-like particles (VLP) expressing the WNV M and E proteins. Immune equine F(ab')₂ fragments and immune horse sera efficiently neutralized WNV infection in tissue culture. The passive transfer of equine immune antibodies significantly accelerated the virus clearance in the spleens and brains of WNV infected mice, and reduced mortality. Thus, equine immunoglobulin or equine neutralizing F(ab')₂ passive immunotherapy is a potential strategy for the prophylactic or therapeutic treatment of patients infected with WNV.

  8. Successful management of severe neuroinvasive eastern equine encephalitis.

    Science.gov (United States)

    Wendell, Linda C; Potter, N Stevenson; Roth, Julie L; Salloway, Stephen P; Thompson, Bradford B

    2013-08-01

    Eastern Equine Encephalitis (EEE) virus is an arbovirus that mostly causes asymptomatic infection in humans; however, some people can develop a neuroinvasive infection associated with a high mortality. We present a case of a patient with severe neuroinvasive EEE. A 21-year-old man initially presented with headache, fever, and vomiting and was found to have a neutrophilic pleocytosis in his cerebrospinal fluid. He eventually was diagnosed with EEE, treated with high-dose methylprednisolone and intravenous immunoglobulin. His course in the NeuroIntensive Care Unit was complicated by cerebral edema and intracranial hypertension, requiring osmotherapy, pentobarbital and placement of an external ventricular device, and subclinical seizures, necessitating multiple anti-epileptic drugs A multifaceted approach including aggressive management of cerebral edema and ICP as well as treatment with immunomodulating agents and cessation of seizures may prevent brain herniation, secondary neurologic injury and death in patients with EEE. Effective management and treatment in our patient contributed to a dramatic recovery and ultimate good outcome.

  9. Chronic herpes simplex virus encephalitis in childhood.

    NARCIS (Netherlands)

    Leen, W.G.; Weemaes, C.M.R.; Verbeek, M.M.; Willemsen, M.A.A.P.; Rotteveel, J.J.

    2006-01-01

    Although herpes simplex virus is a major cause of acute encephalitis in childhood, chronic herpes simplex virus encephalitis has only rarely been reported. This report presents a case of chronic herpes simplex virus encephalitis in a 6-year-old female. Diagnosis was based on the detection of herpes

  10. Spatial epidemiology of eastern equine encephalitis in Florida

    Directory of Open Access Journals (Sweden)

    Vander Kelen Patrick T

    2012-11-01

    Full Text Available Abstract Background Eastern Equine Encephalitis virus (EEEV is an alphavirus with high pathogenicity in both humans and horses. Florida continues to have the highest occurrence of human cases in the USA, with four fatalities recorded in 2010. Unlike other states, Florida supports year-round EEEV transmission. This research uses GIS to examine spatial patterns of documented horse cases during 2005–2010 in order to understand the relationships between habitat and transmission intensity of EEEV in Florida. Methods Cumulative incidence rates of EEE in horses were calculated for each county. Two cluster analyses were performed using density-based spatial clustering of applications with noise (DBSCAN. The first analysis was based on regional clustering while the second focused on local clustering. Ecological associations of EEEV were examined using compositional analysis and Euclidean distance analysis to determine if the proportion or proximity of certain habitats played a role in transmission. Results The DBSCAN algorithm identified five distinct regional spatial clusters that contained 360 of the 438 horse cases. The local clustering resulted in 18 separate clusters containing 105 of the 438 cases. Both the compositional analysis and Euclidean distance analysis indicated that the top five habitats positively associated with horse cases were rural residential areas, crop and pastureland, upland hardwood forests, vegetated non-forested wetlands, and tree plantations. Conclusions This study demonstrates that in Florida tree plantations are a focus for epizootic transmission of EEEV. It appears both the abundance and proximity of tree plantations are factors associated with increased risk of EEE in horses and therefore humans. This association helps to explain why there is are spatially distinct differences in the amount of EEE horse cases across Florida.

  11. Epidemic Venezuelan equine encephalitis in North America in 1971: vector studies.

    Science.gov (United States)

    Sudia, W D; Newhouse, V F; Beadle, I D; Miller, D L; Johnston, J G; Young, R; Calisher, C H; Maness, K

    1975-01-01

    A major epidemic of Venezuelan equine encephalitis occurred in south Texas in the summer of 1971. More than 1500 equines died of VEE in Texas, and 110 human cases with no deaths were reported. Vector studies in south Texas and northern Tamaulipas revealed that the overall mosquito infection rates during the peak of the epidemic were about 1:100, one of the highest rates observed for a major epidemic. Mosquito infection rates of this magnitude could easily explain the intensity of VEE outbreaks in both equines and man. A total of 943 VEE virus isolations were made from mosquitoes. Eight of the 12 mosquito species found infected were implicated in the epidemic cycle of VEE for the first time. Sufficient laboratory and field evidence is available to prove that Psorophora confinnis was one of the primary vectors of VEE. The lack of laboratory evidence necessitates the use of the term "probable" primary vectors for other species apparently equally as involved on the basis of field infections; these include Aedes sollicitans, Aedes thelcter and Psorophora discolor. Eight other species from which less than 10 VEE virus isolations were made were considered auxiliary vectors. Mosquitoes of some species were tested individually; such tests showed 2-4% of the probable primary vectors to be infected. The first isolation of VEE virus of the epidemic was made from P. confinnis on June 28, 1971. Highest mosquito infection rates occurred during the week of July 5. Mosquito infection rates declined precipitously in the last 3 weeks of July 1971, signaling the end of the epidemic in the study area. One explanation for the decline was that equines, the principal epidemic hosts, were eliminated as a source of virus by death or by acquisition of natural or induced immunity. Mosquito control appeared to be effective in reducing the infected mosquito population while the immunization of equines with TC 83 VEE vaccine was accomplished. Quarantines appeared to be effective in restricting

  12. Venezuelan equine encephalitis in Panama: fatal endemic disease and genetic diversity of etiologic viral strains.

    Directory of Open Access Journals (Sweden)

    Evelia Quiroz

    2009-06-01

    Full Text Available Venezuelan equine encephalitis (VEE is a reemerging, mosquito-borne viral disease of the neotropics that is severely debilitating and sometimes fatal to humans. Periodic epidemics mediated by equine amplification have been recognized since the 1920s, but interepidemic disease is rarely recognized. We report here clinical findings and genetic characterization of 42 cases of endemic VEE detected in Panama from 1961-2004. Recent clusters of cases occurred in Darien (eastern Panama and Panama provinces (central Panama near rainforest and swamp habitats. Patients ranged from 10 months to 48 years of age, and the more severe cases with neurological complications, including one fatal infection, were observed in children. The VEE virus strains isolated from these cases all belonged to an enzootic, subtype ID lineage known to circulate among sylvatic vectors and rodent reservoir hosts in Panama and Peru. These findings underscore endemic VEE as an important but usually neglected arboviral disease of Latin America.

  13. Venezuelan Equine Encephalitis in Panama: Fatal Endemic Disease and Genetic Diversity of Etiologic Viral Strains

    Science.gov (United States)

    Quiroz, Evelia; Aguilar, Patricia V.; Cisneros, Julio; Tesh, Robert B.; Weaver, Scott C.

    2009-01-01

    Venezuelan equine encephalitis (VEE) is a reemerging, mosquito-borne viral disease of the neotropics that is severely debilitating and sometimes fatal to humans. Periodic epidemics mediated by equine amplification have been recognized since the 1920s, but interepidemic disease is rarely recognized. We report here clinical findings and genetic characterization of 42 cases of endemic VEE detected in Panama from 1961–2004. Recent clusters of cases occurred in Darien (eastern Panama) and Panama provinces (central Panama) near rainforest and swamp habitats. Patients ranged from 10 months to 48 years of age, and the more severe cases with neurological complications, including one fatal infection, were observed in children. The VEE virus strains isolated from these cases all belonged to an enzootic, subtype ID lineage known to circulate among sylvatic vectors and rodent reservoir hosts in Panama and Peru. These findings underscore endemic VEE as an important but usually neglected arboviral disease of Latin America. PMID:19564908

  14. 21 CFR 866.3240 - Equine encephalomyelitis virus serological reagents.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Equine encephalomyelitis virus serological... § 866.3240 Equine encephalomyelitis virus serological reagents. (a) Identification. Equine... tests to identify antobodies to equine encephalomyelitis virus in serum. The identification aids in the...

  15. Replicon-Helper Systems from Attenuated Venezuelan Equine Encephalitis Virus: Expression of Heterologous Genes in Vitro and Immunization Against Heterologous Pathogens in Vivo

    National Research Council Canada - National Science Library

    Pushko, Peter

    1997-01-01

    ...) or the Lassa virus nucleocapsid (N) gene, and upon transfection into eukaryotic cells by electroportation, these replicon RNAs directed the efficient, high-level synthesis of the HA or N proteins...

  16. Tick-borne encephalitis virus, Kyrgyzstan.

    Science.gov (United States)

    Briggs, Benjamin J; Atkinson, Barry; Czechowski, Donna M; Larsen, Peter A; Meeks, Heather N; Carrera, Juan P; Duplechin, Ryan M; Hewson, Roger; Junushov, Asankadyr T; Gavrilova, Olga N; Breininger, Irena; Phillips, Carleton J; Baker, Robert J; Hay, John

    2011-05-01

    Tick-borne encephalitis virus (TBEV) is an emerging pathogen in Europe and Asia. We investigated TBEV in Kyrgyzstan by collecting small mammals and ticks from diverse localities and analyzing them for evidence of TBEV infection. We found TBEV circulating in Kyrgyzstan much farther south and at higher altitudes than previously reported.

  17. Tick-Borne Encephalitis Virus, Kyrgyzstan

    Science.gov (United States)

    Atkinson, Barry; Czechowski, Donna M.; Larsen, Peter A.; Meeks, Heather N.; Carrera, Juan P.; Duplechin, Ryan M.; Hewson, Roger; Junushov, Asankadyr T.; Gavrilova, Olga N.; Breininger, Irena; Phillips, Carleton J.; Baker, Robert J.; Hay, John

    2011-01-01

    Tick-borne encephalitis virus (TBEV) is an emerging pathogen in Europe and Asia. We investigated TBEV in Kyrgyzstan by collecting small mammals and ticks from diverse localities and analyzing them for evidence of TBEV infection. We found TBEV circulating in Kyrgyzstan much farther south and at higher altitudes than previously reported. PMID:21529400

  18. Analysis of Venezuelan equine encephalitis replicon particles packaged in different coats.

    Science.gov (United States)

    Kamrud, Kurt I; Alterson, Kim D; Andrews, Chasity; Copp, Laura O; Lewis, Whitney C; Hubby, Bolyn; Patel, Deepa; Rayner, Jonathan O; Talarico, Todd; Smith, Jonathan F

    2008-07-16

    The Venezuelan equine encephalitis (VEE) virus replicon system was used to produce virus-like replicon particles (VRP) packaged with a number of different VEE-derived glycoprotein (GP) coats. The GP coat is believed to be responsible for the cellular tropism noted for VRP and it is possible that different VEE GP coats may have different affinities for cells. We examined VRP packaged in four different VEE GP coats for their ability to infect cells in vitro and to induce both humoral and cellular immune responses in vivo. The VRP preparations were characterized to determine both infectious units (IU) and genome equivalents (GE) prior to in vivo analysis. VRP packaged with different VEE GP coats demonstrated widely varying GE/IU ratios based on Vero cell infectivity. BALB/c mice were immunized with the different VRP based on equal GE titers and the humoral and cellular responses to the expressed HIV gag gene measured. The magnitude of the immune responses measured in mice revealed small but significant differences between different GP coats when immunization was based on GE titers. We suggest that care should be taken when alternative coat proteins are used to package vector-based systems as the titers determined by cell culture infection may not represent accurate particle numbers and in turn may not accurately represent actual in vivo dose.

  19. Evolution and spread of Venezuelan equine encephalitis complex alphavirus in the Americas.

    Directory of Open Access Journals (Sweden)

    Naomi L Forrester

    2017-08-01

    Full Text Available Venezuelan equine encephalitis (VEE complex alphaviruses are important re-emerging arboviruses that cause life-threatening disease in equids during epizootics as well as spillover human infections. We conducted a comprehensive analysis of VEE complex alphaviruses by sequencing the genomes of 94 strains and performing phylogenetic analyses of 130 isolates using complete open reading frames for the nonstructural and structural polyproteins. Our analyses confirmed purifying selection as a major mechanism influencing the evolution of these viruses as well as a confounding factor in molecular clock dating of ancestors. Times to most recent common ancestors (tMRCAs could be robustly estimated only for the more recently diverged subtypes; the tMRCA of the ID/IAB/IC/II and IE clades of VEE virus (VEEV were estimated at ca. 149-973 years ago. Evolution of the IE subtype has been characterized by a significant evolutionary shift from the rest of the VEEV complex, with an increase in structural protein substitutions that are unique to this group, possibly reflecting adaptation to its unique enzootic mosquito vector Culex (Melanoconion taeniopus. Our inferred tree topologies suggest that VEEV is maintained primarily in situ, with only occasional spread to neighboring countries, probably reflecting the limited mobility of rodent hosts and mosquito vectors.

  20. Analysis of Venezuelan equine encephalitis replicon particles packaged in different coats.

    Directory of Open Access Journals (Sweden)

    Kurt I Kamrud

    2008-07-01

    Full Text Available The Venezuelan equine encephalitis (VEE virus replicon system was used to produce virus-like replicon particles (VRP packaged with a number of different VEE-derived glycoprotein (GP coats. The GP coat is believed to be responsible for the cellular tropism noted for VRP and it is possible that different VEE GP coats may have different affinities for cells. We examined VRP packaged in four different VEE GP coats for their ability to infect cells in vitro and to induce both humoral and cellular immune responses in vivo.The VRP preparations were characterized to determine both infectious units (IU and genome equivalents (GE prior to in vivo analysis. VRP packaged with different VEE GP coats demonstrated widely varying GE/IU ratios based on Vero cell infectivity. BALB/c mice were immunized with the different VRP based on equal GE titers and the humoral and cellular responses to the expressed HIV gag gene measured. The magnitude of the immune responses measured in mice revealed small but significant differences between different GP coats when immunization was based on GE titers.We suggest that care should be taken when alternative coat proteins are used to package vector-based systems as the titers determined by cell culture infection may not represent accurate particle numbers and in turn may not accurately represent actual in vivo dose.

  1. Epidemiology of Emergent Madariaga Encephalitis in a Region with Endemic Venezuelan Equine Encephalitis: Initial Host Studies and Human Cross-Sectional Study in Darien, Panama.

    Directory of Open Access Journals (Sweden)

    Amy Y Vittor

    2016-04-01

    Full Text Available Neurotropic arboviral infections are an important cause of encephalitis. A zoonotic, vector-borne alphavirus, Madariaga virus (MADV; formerly known as South American eastern equine encephalitis virus, caused its first documented human outbreak in 2010 in Darien, Panama, where the genetically similar Venezuelan equine encephalitis virus (VEEV is endemic. We report the results of a seroprevalence survey of animals and humans, illustrating contrasting features of MADV and VEEV ecology and epidemiology.Small mammals were trapped in 42 sites in Darien, Panama, using Sherman traps, Tomahawk traps, and mist nets for bats. Blood was tested for the presence of neutralizing antibodies to MADV and VEEV. In addition, bird sera collected in 2007 in Chagres, Panama, were tested for MADV and VEEV neutralizing antibodies. Viremia was ascertained by RT-PCR. Human exposure to these two viruses was determined by IgG ELISA, followed by plaque reduction neutralization tests. To identify relevant risk factors for MADV or VEEV exposure, logistic regression analysis was performed, and the most parsimonious model was selected based on the Akaike information criterion.The animal survey yielded 32 bats (16 species, 556 rodents (12 species, and 20 opossums (4 species. The short-tailed cane mouse (Zygodontomys brevicauda found abundantly in pasture and farms, had the highest MADV seroprevalence (8.3%. For VEEV, the shrub and forest-dwelling long-whiskered rice rat (Transandinomys bolivaris had the highest seroprevalence (19.0%. Viremia was detected in one animal (Z. brevicauda. Of the 159 bird sera (50 species tested, none were positive for either virus. In humans (n = 770, neutralizing antibodies to MADV and VEEV were present in 4.8% and 31.5%, respectively. MADV seropositivity was positively associated with cattle ranching, farming, and fishing. Having VEEV antibodies and shrubs near the house diminished risk. Age, forest work, farming and fishing were risk factors for

  2. [Mosquitos (Diptera: Culicidae) in the small village where a human case of Venezuelan equine encephalitis was recorded].

    Science.gov (United States)

    Ferro, Cristina; Olano, Víctor Alberto; Ahumada, Martha; Weaver, Scott

    2008-06-01

    The enzootic focus of subtype ID of Venezuelan equine encephalitis (VEE) virus in the Central Magdalena region (central Colombia) occasionally produces human cases. The report of a VEE infection in a three-year-old girl in the small Chingalé, municipalitype of Puerto Wilches, Santander, motivated this study. The village of Chingalé was evaluated as the probable site of infection. In June 2005, mosquitoes were collected with CDC light traps in and outside of dwellings in the village. Trinidad traps were placed in nearby vegetation, and hamsters were used as sentinel animals near homes. One hundred and seven samples, consisting of 14,423 mosquitoes of 35 species were collected. The relative abundance of incriminated vectors of subtype ID of VEE, Culex (Melanoconion) pedroi and Cx. (Mel.) ocossa, was generally low (mosquitoes of the subgenus Melanoconion carried the virus into the village from a neighboring habitat.

  3. Japanese encephalitis virus infection, diagnosis and control in domestic animals.

    Science.gov (United States)

    Mansfield, Karen L; Hernández-Triana, Luis M; Banyard, Ashley C; Fooks, Anthony R; Johnson, Nicholas

    2017-03-01

    Japanese encephalitis virus (JEV) is a significant cause of neurological disease in humans throughout Asia causing an estimated 70,000 human cases each year with approximately 10,000 fatalities. The virus contains a positive sense RNA genome within a host-derived membrane and is classified within the family Flaviviridae. Like many flaviviruses, it is transmitted by mosquitoes, particularly those of the genus Culex in a natural cycle involving birds and some livestock species. Spill-over into domestic animals results in a spectrum of disease ranging from asymptomatic infection in some species to acute neurological signs in others. The impact of JEV infection is particularly apparent in pigs. Although infection in adult swine does not result in symptomatic disease, it is considered a significant reproductive problem causing abortion, still-birth and birth defects. Infected piglets can display fatal neurological disease. Equines are also infected, resulting in non-specific signs including pyrexia, but occasionally leading to overt neurological disease that in extreme cases can lead to death. Veterinary vaccination is available for both pigs and horses. This review of JEV disease in livestock considers the current diagnostic techniques available for detection of the virus. Options for disease control and prevention within the veterinary sector are discussed. Such measures are critical in breaking the link to zoonotic transmission into the human population where humans are dead-end hosts. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  4. Serological evidence of widespread circulation of West Nile virus and other flaviviruses in equines of the Pantanal, Brazil.

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    Alex Pauvolid-Corrêa

    2014-02-01

    Full Text Available A recent study reported neutralizing antibodies to West Nile virus (WNV in horses from four ranches of southern Pantanal. To extend that study, a serosurvey for WNV and 11 Brazilian flaviviruses was conducted with 760 equines, 238 sheep and 61 caimans from 17 local cattle ranches. Among the tested equines, 32 were collected from a ranch where a neurologic disorder outbreak had been recently reported. The sera were initially screened by using a blocking ELISA and then titrated by 90% plaque-reduction neutralization test (PRNT90 for 12 flaviviruses. Employing the criterion of 4-fold greater titer, 78 (10.3% equines were seropositive for Ilheus virus, 59 (7.8% for Saint Louis encephalitis virus, 24 (3.2% for WNV, two (0.3% for Cacipacore virus and one (0.1% for Rocio virus. No serological evidence was found linking the neurological disease that affected local equines to WNV. All caimans and sheep were negative by blocking ELISA for flaviviruses. There were no seropositive equines for Bussuquara, Iguape, Yellow fever and all four Dengue virus serotypes. The detection of WNV-seropositive equines in ten ranches and ILHV and SLEV-seropositive equines in fourteen ranches of two different sub-regions of Pantanal is strong evidence of widespread circulation of these flaviviruses in the region.

  5. Serological evidence of widespread circulation of West Nile virus and other flaviviruses in equines of the Pantanal, Brazil.

    Science.gov (United States)

    Pauvolid-Corrêa, Alex; Campos, Zilca; Juliano, Raquel; Velez, Jason; Nogueira, Rita Maria Ribeiro; Komar, Nicholas

    2014-02-01

    A recent study reported neutralizing antibodies to West Nile virus (WNV) in horses from four ranches of southern Pantanal. To extend that study, a serosurvey for WNV and 11 Brazilian flaviviruses was conducted with 760 equines, 238 sheep and 61 caimans from 17 local cattle ranches. Among the tested equines, 32 were collected from a ranch where a neurologic disorder outbreak had been recently reported. The sera were initially screened by using a blocking ELISA and then titrated by 90% plaque-reduction neutralization test (PRNT90) for 12 flaviviruses. Employing the criterion of 4-fold greater titer, 78 (10.3%) equines were seropositive for Ilheus virus, 59 (7.8%) for Saint Louis encephalitis virus, 24 (3.2%) for WNV, two (0.3%) for Cacipacore virus and one (0.1%) for Rocio virus. No serological evidence was found linking the neurological disease that affected local equines to WNV. All caimans and sheep were negative by blocking ELISA for flaviviruses. There were no seropositive equines for Bussuquara, Iguape, Yellow fever and all four Dengue virus serotypes. The detection of WNV-seropositive equines in ten ranches and ILHV and SLEV-seropositive equines in fourteen ranches of two different sub-regions of Pantanal is strong evidence of widespread circulation of these flaviviruses in the region.

  6. Identification of Aedes campestris from New Mexico: with notes on the isolation of western equine encephalitis and other arboviruses.

    Science.gov (United States)

    Clark, G G; Crabbs, C L; Bailey, C L; Calisher, C H; Craig, G B

    1986-12-01

    An arbovirus survey was conducted during August 1985 at White Sands Missile Range in southcentral New Mexico following a suspected arboviral disease epizootic among feral horses. A total of 20,566 mosquitoes (18,505 females and 2,061 males) and 8,900 biting gnats were collected and assayed for virus. Female mosquitoes were principally Aedes campestris (54.8%), Aedes dorsalis (30.4%) and Culex tarsalis (13.2%). Arboviruses were not isolated from biting gnats, but mosquitoes yielded a total of 37 viral isolates, including western equine encephalitis (WEE) (18), California serogroup (15), Cache Valey (1), and Hart Park (1) viruses in addition to 2, as yet unidentified, rhabdoviruses. Isolates of WEE virus were from 9 pools of Ae. campestris, 6 of Cx. tarsalis and 3 of Ae. dorsalis. California serogroup viruses, including 2 subtypes, were obtained from 7 pools of females and 1 pool of males of Ae. campestris and from 4 pools of Ae. dorsalis. Cache Valley and Hart Park viruses were isolated from single pools of Ae. dorsalis and Cx. tarsalis, respectively, and the rhabdoviruses were obtained from Ae. campestris and Psorophora signipennis.

  7. Ocular histopathology in Eastern equine encephalitis: A case report

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    Eleonora M. Lad

    2017-04-01

    Conclusions and importance: To our knowledge, this is the first report of ophthalmological and ocular pathology observations in an EEE patient. Interestingly, the inflammatory findings in the retina are reminiscent of the central nervous system effects of EEE virus. These findings are relevant given the recent epidemic of microcephaly and ophthalmic complications secondary to another arboviral virus, the Zika virus.

  8. Eastern equine encephalitis in Massachusetts: a report of 16 cases, 1970-1984.

    Science.gov (United States)

    Przelomski, M M; O'Rourke, E; Grady, G F; Berardi, V P; Markley, H G

    1988-05-01

    We studied the case records of 16 patients with eastern equine encephalitis (EEE) in Massachusetts from 1970 to 1984 and compared their presentations, courses, and outcomes with the data available from previous epidemics. In recent years, there has been a greater frequency of EEE in adults, whereas in the past it was considered a disease of children. Also, prognosis for a good functional recovery seems to be correlated with age over 40 years, a long prodromal course (5 to 7 days) of constitutional symptoms, and the absence of coma. Previous reports did not mention these significant correlations. We also stress the positive and negative diagnostic correlations, in order to distinguish between EEE and herpes simplex encephalitis.

  9. Japanese encephalitis: the virus and vaccines.

    Science.gov (United States)

    Yun, Sang-Im; Lee, Young-Min

    2014-01-01

    Japanese encephalitis (JE) is an infectious disease of the central nervous system caused by Japanese encephalitis virus (JEV), a zoonotic mosquito-borne flavivirus. JEV is prevalent in much of Asia and the Western Pacific, with over 4 billion people living at risk of infection. In the absence of antiviral intervention, vaccination is the only strategy to develop long-term sustainable protection against JEV infection. Over the past half-century, a mouse brain-derived inactivated vaccine has been used internationally for active immunization. To date, however, JEV is still a clinically important, emerging, and re-emerging human pathogen of global significance. In recent years, production of the mouse brain-derived vaccine has been discontinued, but 3 new cell culture-derived vaccines are available in various parts of the world. Here we review current aspects of JEV biology, summarize the 4 types of JEV vaccine, and discuss the potential of an infectious JEV cDNA technology for future vaccine development.

  10. Human Hendra virus infection causes acute and relapsing encephalitis.

    Science.gov (United States)

    Wong, K T; Robertson, T; Ong, B B; Chong, J W; Yaiw, K C; Wang, L F; Ansford, A J; Tannenberg, A

    2009-06-01

    To study the pathology of two cases of human Hendra virus infection, one with no clinical encephalitis and one with relapsing encephalitis. Autopsy tissues were investigated by light microscopy, immunohistochemistry and in situ hybridization. In the patient with acute pulmonary syndrome but not clinical acute encephalitis, vasculitis was found in the brain, lung, heart and kidney. Occasionally, viral antigens were demonstrated in vascular walls but multinucleated endothelial syncytia were absent. In the lung, there was severe inflammation, necrosis and viral antigens in type II pneumocytes and macrophages. The rare kidney glomerulus showed inflammation and viral antigens in capillary walls and podocytes. Discrete necrotic/vacuolar plaques in the brain parenchyma were associated with antigens and viral RNA. Brain inflammation was mild although CD68(+) microglia/macrophages were significantly increased. Cytoplasmic viral inclusions and antigens and viral RNA in neurones and ependyma suggested viral replication. In the case of relapsing encephalitis, there was severe widespread meningoencephalitis characterized by neuronal loss, macrophages and other inflammatory cells, reactive blood vessels and perivascular cuffing. Antigens and viral RNA were mainly found in neurones. Vasculitis was absent in all the tissues examined. The case of acute Hendra virus infection demonstrated evidence of systemic infection and acute encephalitis. The case of relapsing Hendra virus encephalitis showed no signs of extraneural infection but in the brain, extensive inflammation and infected neurones were observed. Hendra virus can cause acute and relapsing encephalitis and the findings suggest that the pathology and pathogenesis are similar to Nipah virus infection.

  11. Herpes simplex encephalitis : from virus to therapy.

    Science.gov (United States)

    Rozenberg, Flore; Deback, Claire; Agut, Henri

    2011-06-01

    Herpes simplex virus (HSV) is the cause of herpes simplex encephalitis (HSE), a devastating human disease which occurs in 2-4 cases per million/year. HSE results either from a primary infection or virus reactivation, in accordance with the common pattern of HSV infection which is a chronic lifelong process. However its pathophysiology remains largely unknown and its poor prognosis is in contrast with the usually good tolerance of most clinical herpetic manifestations. HSE is due to HSV type 1 (HSV-1) in most cases but HSV type 2 (HSV-2) may be also implicated, especially in infants in the context of neonatal herpes. Polymerase chain reaction detection of HSV DNA in cerebrospinal fluid is the diagnosis of choice for HSE. Acyclovir, a nucleoside analogue which inhibits viral DNA polymerase activity, is the reference treatment of HSE while foscarnet constitutes an alternative therapy and the efficacy of cidofovir is currently uncertain in that context. The emergence of HSV resistance to acyclovir, a phenomenon which is mainly observed among immunocompromised patients, is a current concern although no case of HSE due to an acyclovir-resistant HSV strain has been reported to date. Nevertheless the identification and development of novel therapeutic strategies against HSV appears to be a non dispensable objective for future research in virology.

  12. PRESENCE OF RESPIRATORY VIRUSES IN EQUINES IN BRAZIL

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    Dalva Assunção Portari Mancini

    2014-06-01

    Full Text Available Equines are susceptible to respiratory viruses such as influenza and parainfluenza. Respiratory diseases have adversely impacted economies all over the world. This study was intended to determine the presence of influenza and parainfluenza viruses in unvaccinated horses from some regions of the state of São Paulo, Brazil. Blood serum collected from 72 equines of different towns in this state was tested by hemagglutination inhibition test to detect antibodies for both viruses using the corresponding antigens. About 98.6% (71 and 97.2% (70 of the equines responded with antibody protective titers (≥ 80 HIU/25µL H7N7 and H3N8 subtypes of influenza A viruses, respectively. All horses (72 also responded with protective titers (≥ 80 HIU/25µL against the parainfluenza virus. The difference between mean antibody titers to H7N7 and H3N8 subtypes of influenza A viruses was not statistically significant (p > 0.05. The mean titers for influenza and parainfluenza viruses, on the other hand, showed a statistically significant difference (p < 0.001. These results indicate a better antibody response from equines to parainfluenza 3 virus than to the equine influenza viruses. No statistically significant differences in the responses against H7N7 and H3N8 subtypes of influenza A and parainfluenza 3 viruses were observed according to the gender (female, male or the age (≤ 2 to 20 years-old groups. This study provides evidence of the concomitant presence of two subtypes of the equine influenza A (H7N7 and H3N8 viruses and the parainfluenza 3 virus in equines in Brazil. Thus, it is advisable to vaccinate equines against these respiratory viruses.

  13. Epstein-Barr virus encephalitis and encephalomyelitis: MR findings

    Energy Technology Data Exchange (ETDEWEB)

    Shian, W.J. [Department of Pediatrics, Tao-Yuan Veterans Hospital, No. 100, Sec 3, Cheng-Kung Rd, City of Tao-Yuan, Taiwan (Taiwan, Province of China); Chi, C.S. [Department of Pediatrics, Taichung Veterans General Hospital, Taichung, Taiwan (Taiwan, Province of China)

    1996-09-01

    The purpose of this project is to investigate the clinical and brain MR characteristics of Epstein-Barr virus (EBV) encephalitis and encephalomyelitis. Clinical and 30 MR findings of 29 patients with EBV encephalitis or encephalomyelitis were retrospectively reviewed. Patients included 24 with encephalitis, 3 with encephalomyelitis, and 2 with brain-stem encephalitis. Altered consciousness, seizures, visual hallucination, and acute psychotic reaction were the common presentations. Eight patients had positive MR findings. These included T2 prolongation over gray and white matter, periventricular leukomalacia, and brain atrophy. Transient T2 prolongation over gray and white matter was found in one patient. Our results indicate that EBV encephalitis and encephalomyelitis have a wide range of both clinical and MR findings. The MR lesions may disappear in a short period, so the timing for the MR scan may be critical. (orig.). With 5 figs., 2 tabs.

  14. A Review of Evidence that Equine Influenza Viruses Are Zoonotic

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    Tai Xie

    2016-07-01

    Full Text Available Among scientists, there exist mixed opinions whether equine influenza viruses infect man. In this report, we summarize a 2016 systematic and comprehensive review of the English, Chinese, and Mongolian scientific literature regarding evidence for equine influenza virus infections in man. Searches of PubMed, Web of Knowledge, ProQuest, CNKI, Chongqing VIP Database, Wanfang Data and MongolMed yielded 2831 articles, of which 16 met the inclusion criteria for this review. Considering these 16 publications, there was considerable experimental and observational evidence that at least H3N8 equine influenza viruses have occasionally infected man. In this review we summarize the most salient scientific reports.

  15. Unilateral Negative Myoclonus Caused by Herpes Simplex Virus Encephalitis

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    Jin-Mo Park

    2011-05-01

    Full Text Available Various neurologic manifestations of herpes simplex virus (HSV encephalitis have been reported on the literatures. Chorea, ballism, choreoathetosis and myoclonus were reported as movement disorders which might be related with brain lesion by HSV encephalitis, but negative myoclonus (NM has never been reported before. NM can be characterized as a shock-like involuntary jerky movement caused by a sudden, brief interruption of muscle activity. We experienced a case of HSV encephalitis with NM in unilateral arm and leg. In polygraphic monitoring, electroencephalography (EMG silent periods are 50–250 ms in duration with no detectable EMG correlate.

  16. Immune responses to commercial equine vaccines against equine herpesvirus-1, equine influenza virus, eastern equine encephalomyelitis, and tetanus.

    Science.gov (United States)

    Holmes, Mark A; Townsend, Hugh G G; Kohler, Andrea K; Hussey, Steve; Breathnach, Cormac; Barnett, Craig; Holland, Robert; Lunn, D P

    2006-05-15

    Horses are commonly vaccinated to protect against pathogens which are responsible for diseases which are endemic within the general horse population, such as equine influenza virus (EIV) and equine herpesvirus-1 (EHV-1), and against a variety of diseases which are less common but which lead to greater morbidity and mortality, such as eastern equine encephalomyelitis virus (EEE) and tetanus. This study consisted of two trials which investigated the antigenicity of commercially available vaccines licensed in the USA to protect against EIV, EHV-1 respiratory disease, EHV-1 abortion, EEE and tetanus in horses. Trial I was conducted to compare serological responses to vaccines produced by three manufacturers against EIV, EHV-1 (respiratory disease), EEE, and tetanus given as multivalent preparations or as multiple vaccine courses. Trial II compared vaccines from two manufacturers licensed to protect against EHV-1 abortion, and measured EHV-1-specific interferon-gamma (IFN-gamma) mRNA production in addition to serological evidence of antigenicity. In Trial I significant differences were found between the antigenicity of different commercial vaccines that should be considered in product selection. It was difficult to identify vaccines that generate significant immune responses to respiratory viruses. The most dramatic differences in vaccine performance occurred in the case of the tetanus antigen. In Trial II both vaccines generated significant antibody responses and showed evidence of EHV-1-specific IFN-gamma mRNA responses. Overall there were wide variations in vaccine response, and the vaccines with the best responses were not produced by a single manufacturer. Differences in vaccine performance may have resulted from differences in antigen load and adjuvant formulation.

  17. Affinity (tropism) of caprine arthritis encephalitis virus for brain cells ...

    African Journals Online (AJOL)

    In this study, explant cultures prepared from the brain of new-born goat-kid were infected with. Caprine Arthritis Encephalitis (CAE) virus- a retrovirus affecting goats. The specific brain cell types infected by the (CAE) virus were determined using reverse-transcription polymerase chain reaction (RTPCR) and transmission ...

  18. Identification and isolation of Genotype-I Japanese Encephalitis virus from encephalitis patients

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    Gao Xiaoyan

    2010-11-01

    Full Text Available Abstract Historically, Japanese Encephalitis virus (JEV genotype III (GIII has been responsible for human diseases. In recent years, JEV genotype I (GI has been isolated from mosquitoes collected in numerous countries, but has not been isolated from patients with encephalitis. In this study, we report recovery of JEV GI live virus and identification of JEV GI RNA from cerebrospinal fluid (CSF of encephalitis patients in JE endemic areas of China. Whole-genome sequencing and molecular phylogenetic analysis of the JEV isolate from the CSF samples was performed. The isolate in this study is highly similar to other JEV GI strains which isolated from mosquitoes at both the nucleotide and deduced amino acid levels. Phylogenetic analysis based on the genomic sequence showed that the isolate belongs to JEV GI, which is consistent with the phylogenetic analysis based on the pre-membrane (PrM and Glycoprotein genes. As a conclusion, this is the first time to isolate JEV GI strain from CSF samples of encephalitis patients, so continuous survey and evaluate the infectivity and pathogenecity of JEV GI strains are necessary, especially for the JEV GI strains from encephalitis patients. With respect to the latter, because all current JEV vaccines (live and inactivated are derived from JEV GIII strains, future studies should be aimed at investigating and monitoring cross-protection of the human JEV GI isolates against widely used JEV vaccines.

  19. Herpes Simplex Virus (HSV-1 Encephalitis Mimicking Glioblastoma: Case Report and Review of the Literature

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    Burke A. Cunha

    2014-12-01

    Full Text Available Glioblastoma multiforme (GBM often presents as a brain mass with encephalitis. In a patient with GBM, subsequent presentation with new onset encephalitis may be due to another GBM or Herpes simplex virus 1 (HSV-1 encephalitis. We present a case of HSV-1 encephalitis mimicking GBM in a patient with previous GBM.

  20. Genotype v Japanese encephalitis virus is emerging

    National Research Council Canada - National Science Library

    Li, Ming-Hua; Fu, Shi-Hong; Chen, Wei-Xin; Wang, Huan-Yu; Guo, Yu-Hong; Liu, Qi-Yong; Li, Yi-Xing; Luo, Hui-Ming; Da, Wa; Duo Ji, Dun Zhu; Ye, Xiu-Min; Liang, Guo-Dong

    2011-01-01

    Japanese encephalitis (JE) is a global public health issue that has spread widely to more than 20 countries in Asia and has extended its geographic range to the south Pacific region including Australia...

  1. Seroconversion for west Nile and St. Louis encephalitis viruses among sentinel horses in Colombia

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    Salim Mattar

    2011-12-01

    Full Text Available We prospectively sampled flavivirus-naïve horses in northern Colombia to detect West Nile virus (WNV and St. Louis encephalitis virus (SLEV seroconversion events, which would indicate the current circulation of these viruses. Overall, 331 (34.1% of the 971 horses screened were positive for past infection with flaviviruses upon initial sampling in July 2006. During the 12-month study from July 2006-June 2007, 33 WNV seroconversions and 14 SLEV seroconversions were detected, most of which occurred in the department of Bolivar. The seroconversion rates of horses in Bolivar for the period of March-June 2007 reached 12.4% for WNV and 6.7% for SLEV. These results comprise the first serologic evidence of SLEV circulation in Colombia. None of the horses sampled developed symptoms of encephalitis within three years of initial sampling. Using seroconversions in sentinel horses, we demonstrated an active circulation of WNV and SLEV in northern Colombia, particularly in the department of Bolivar. The absence of WNV-attributed equine or human disease in Colombia and elsewhere in the Caribbean Basin remains a topic of debate and speculation.

  2. New potential antivirals against tick-borne encephalitis virus infection

    OpenAIRE

    VESELKOVÁ, Barbora

    2013-01-01

    The experimental work of the thesis was concentrated on studying of the inhibition effect of twenty-six chemical substances on tick-borne encephalitis virus. The substances showing inhibition effect in High Throughput Screening assay were processed to Cytotoxicity assay, where their toxic effect on tissue cell cultures was determined. Subsequently, substances with inhibition effect and no cytotoxic effect were incubated with cell culture and virus in two different incubation time periods and ...

  3. Media attention and public perceptions of cancer and eastern equine encephalitis.

    Science.gov (United States)

    Ackerson, Leland K; Viswanath, Kasisomayajula

    2010-08-01

    Previous research has found that members of the public have a skewed sense of health risk. The purpose of this research was to investigate how mass media use influences perceptions of threat from cancer and eastern equine encephalitis (EEE). Investigators performed a media content analysis of 253 health-related articles from 11 Massachusetts newspapers, then used logistic regression to analyze responses to a health communication survey of 613 Massachusetts adults. A greater proportion of cancer articles compared to those about EEE mentioned progress in combating the disease (61.0% vs. 16.2%, P EEE articles mentioned new incidents of illness (35.4%, vs. 4.6% P EEE as an equal or greater threat than cancer. Paying a lot of attention to health media was related to higher odds of perceiving EEE as a threat (OR 2.14; 95% CI 1.03-4.45), and of perceiving EEE as a threat compared to cancer (OR 2.18; 95% CI 1.24-3.84). Media treatment of health stories that emphasize the novelty and unpredictability of EEE compared to cancer may lead to distorted perceptions of threat among news consumers.

  4. Mosquito-Host Interactions during and after an Outbreak of Equine Viral Encephalitis in Eastern Panama

    Science.gov (United States)

    Navia-Gine, Wayra G.; Loaiza, Jose R.; Miller, Matthew J.

    2013-01-01

    Mosquito blood meals provide information about the feeding habits and host preference of potential arthropod-borne disease vectors. Although mosquito-borne diseases are ubiquitous in the Neotropics, few studies in this region have assessed patterns of mosquito-host interactions, especially during actual disease outbreaks. Based on collections made during and after an outbreak of equine viral encephalitis, we identified the source of 338 blood meals from 10 species of mosquitoes from Aruza Abajo, a location in Darien province in eastern Panama. A PCR based method targeting three distinct mitochondrial targets and subsequent DNA sequencing was used in an effort to delineate vector-host relationships. At Aruza Abajo, large domesticated mammals dominated the assemblage of mosquito blood meals while wild bird and mammal species represented only a small portion of the blood meal pool. Most mosquito species fed on a variety of hosts; foraging index analysis indicates that eight of nine mosquito species utilize hosts at similar proportions while a stochastic model suggests dietary overlap among species was greater than would be expected by chance. The results from our null-model analysis of mosquito diet overlap are consistent with the hypothesis that in landscapes where large domestic animals dominate the local biomass, many mosquito species show little host specificity, and feed upon hosts in proportion to their biomass, which may have implications for the role of livestocking patterns in vector-borne disease ecology. PMID:24339965

  5. Mosquito-host interactions during and after an outbreak of equine viral encephalitis in Eastern Panama.

    Directory of Open Access Journals (Sweden)

    Wayra G Navia-Gine

    Full Text Available Mosquito blood meals provide information about the feeding habits and host preference of potential arthropod-borne disease vectors. Although mosquito-borne diseases are ubiquitous in the Neotropics, few studies in this region have assessed patterns of mosquito-host interactions, especially during actual disease outbreaks. Based on collections made during and after an outbreak of equine viral encephalitis, we identified the source of 338 blood meals from 10 species of mosquitoes from Aruza Abajo, a location in Darien province in eastern Panama. A PCR based method targeting three distinct mitochondrial targets and subsequent DNA sequencing was used in an effort to delineate vector-host relationships. At Aruza Abajo, large domesticated mammals dominated the assemblage of mosquito blood meals while wild bird and mammal species represented only a small portion of the blood meal pool. Most mosquito species fed on a variety of hosts; foraging index analysis indicates that eight of nine mosquito species utilize hosts at similar proportions while a stochastic model suggests dietary overlap among species was greater than would be expected by chance. The results from our null-model analysis of mosquito diet overlap are consistent with the hypothesis that in landscapes where large domestic animals dominate the local biomass, many mosquito species show little host specificity, and feed upon hosts in proportion to their biomass, which may have implications for the role of livestocking patterns in vector-borne disease ecology.

  6. Parasitic Cowbirds have increased immunity to West Nile and other mosquitoborne encephalitis viruses

    Science.gov (United States)

    Reisen, W.K.; Hahn, D.C.

    2006-01-01

    The rapid geographic spread of West Nile Virus [WNV, Flaviviridae, Flavivirus] across the United States has stimulated interest in comparative host infection studies of avian species to delineate competent reservoir hosts critical for viral amplification. Striking taxonomic differences in avian susceptibility have been noted, offering the opportunity to strategically select species on the basis of life history traits to examine aspects of pathogen virulence or host immunity. We hypothesized that avian brood parasites would show increased resistance to pathogens compared to related taxa, because they have been exposed in their evolutionary history to a wide array of infectious organisms from their different parenting species. The Brown-headed Cowbird (Molothrus ater) is a generalist brood parasite that parasitizes 200+ North American species. Elevated exposure to other species? parasites may have created an unusual degree of pathogen resistance. We compared the relative susceptibility of adult cowbirds to three closely-related non-parasitic species, Red-winged blackbirds, Tricolored blackbirds and Brewer?s blackbirds, to invading NY99 strain of WNV that is highly virulent for many passeriform birds. Previously we had experimentally infected these species with two North American mosquitoborne encephalitis viruses, western equine encephalomyelitis virus [WEEV, Togaviridae, Alphavirus] and St. Louis encephalitis virus [SLEV, Flaviviridae, Flavivirus]. Our results showed that cowbirds exhibited significantly lower viremia responses against all three viruses as well as after co-infection with both WEEV and WNV than did the three related, non-parasitic species. These data supported our hypothesis and indicated that cowbirds were more resistant to infection to both native and introduced viruses.

  7. Nipah virus encephalitis: A cause for concern for Indian neurologists?

    Directory of Open Access Journals (Sweden)

    Halder Amit

    2006-01-01

    Full Text Available The first and only recorded outbreak of Nipah virus (NV encephalitis in India occurred in the winter of 2001, although the causative organism could only be identified 5 years down the line in 2006. The first ever-recorded outbreak of NV encephalitis occurred in the Malaysian peninsula in 1998-99; though between 2001 and 2005, at least four outbreaks occurred in our neighboring country of Bangladesh. The threat of further outbreaks of this dangerous disease looms large on the Indian subcontinent, given the natural reservoir of the definitive host, namely, fruit-eating bats of the genus Pteropus. This review would briefly highlight the epidemiology, clinical aspects and diagnosis of NV encephalitis to enlighten the neurological community of the country for early detection and implementation of preventive measures in the event of further outbreaks, especially those which are generally passed of as ′mystery diseases′ in the lay press and even by governmental agencies.

  8. Computed tomography in young children with herpes simplex virus encephalitis

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    Sugimoto, T.; Woo, M.; Okazaki, H.; Nishida, N.; Hara, T.; Yasuhara, A.; Kasahara, M.; Kobayashi, Y.

    1985-09-01

    Computed tomographic (CT) scans were obtained from eight infants and young children with herpes simplex virus encephalitis. In two cases the initial scan showed diffuse edematous changes as a mass effect without laterality. Unilateral localized low attenuation in the initial scan was evident 4 days after the onset in one patient, and high attenuation in the initial scan appeared on the 6th day in another patient, but in general, it was not possible to establish an early diagnosis of herpes simplex virus encephalitis from CT scan. In the longitudinal study the calcification with ventriculomegaly appeared in 3 of 5 survivors, and gyriform calcification in 2 of 3 patients, respectively. The appearance of multicystic encephalomalacia was evident in one patient 6 months after the onset of neonatal herpes simplex encephalitis. It is shown that the CT findings of neonates and young children with herpes simplex encephalitis are different from those of older children and adults, and the importance of longitudinal CT studies was stressed in clarifying the pathophysiology of the central nervous system involvement in survivors.

  9. Computed tomography in young children with herpes simplex virus encephalitis.

    Science.gov (United States)

    Sugimoto, T; Woo, M; Okazaki, H; Nishida, N; Hara, T; Yasuhara, A; Kasahara, M; Kobayashi, Y

    1985-01-01

    Computed tomographic (CT) scans were obtained from eight infants and young children with herpes simplex virus encephalitis. In two cases the initial scan showed diffuse edematous changes as a mass effect without laterality. Unilateral localized low attenuation in the initial scan was evident 4 days after the onset in one patient, and high attenuation in the initial scan appeared on the 6th day in another patient, but in general, it was not possible to establish an early diagnosis of herpes simplex virus encephalitis from CT scan. In the longitudinal study the calcification with ventriculomegaly appeared in 3 of 5 survivors, and gyriform calcification in 2 of 3 patients, respectively. The appearance of multicystic encephalomalacia was evident in one patient 6 months after the onset of neonatal herpes simplex encephalitis. It is shown that the CT findings of neonates and young children with herpes simplex encephalitis are different from those of older children and adults, and the importance of longitudinal CT studies was stressed in clarifying the pathophysiology of the central nervous system involvement in survivors.

  10. TLR3 Mutations in Adult Patients With Herpes Simplex Virus and Varicella-Zoster Virus Encephalitis.

    Science.gov (United States)

    Sironi, Manuela; Peri, Anna Maria; Cagliani, Rachele; Forni, Diego; Riva, Stefania; Biasin, Mara; Clerici, Mario; Gori, Andrea

    2017-05-01

    Defects in genes of the Toll-like receptor 3 (TLR3) pathway are associated with susceptibility to herpes simplex virus type 1 encephalitis (HSE). We analyzed a cohort of 11 adult Italian patients in whom viral encephalitis developed. We detected 2 rare missense mutations in TLR3: 1 in a patient with HSE (p.Leu297Val) and 1 in a patient with varicella-zoster virus encephalitis (p.Leu199Phe). Both mutations are extremely rare in human populations and have pathogenicity scores highly suggestive of a functional effect. Data herein expand the phenotypic spectrum of TLR3 mutations to varicella-zoster virus encephalitis and support the role of TLR3 genetic defects as risk factors for HSE in adults. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  11. Equine Arteritis Virus Uses Equine CXCL16 as an Entry Receptor

    Science.gov (United States)

    Sarkar, Sanjay; Chelvarajan, Lakshman; Cook, Frank; Artiushin, Sergey; Mondal, Shankar; Anderson, Kelsi; Eberth, John; Timoney, Peter J.; Kalbfleisch, Theodore S.; Bailey, Ernest

    2016-01-01

    ABSTRACT Previous studies in our laboratory have identified equine CXCL16 (EqCXCL16) to be a candidate molecule and possible cell entry receptor for equine arteritis virus (EAV). In horses, the CXCL16 gene is located on equine chromosome 11 (ECA11) and encodes a glycosylated, type I transmembrane protein with 247 amino acids. Stable transfection of HEK-293T cells with plasmid DNA carrying EqCXCL16 (HEK-EqCXCL16 cells) increased the proportion of the cell population permissive to EAV infection from equine industry from high rates of abortion in pregnant mares, death in young foals, establishment of the carrier state in stallions, and trade restrictions imposed by various countries. Similar to other arteriviruses, EAV primarily targets cells of the monocyte/macrophage lineage, which, when infected, are believed to play a critical role in EVA pathogenesis. To this point, however, the host-specified molecules involved in EAV binding and entry into monocytes/macrophages have not been identified. Identification of the cellular receptors for EAV may provide insights to design antivirals and better prophylactic reagents. In this study, we have demonstrated that EqCXCL16 acts as an EAV entry receptor in EAV-susceptible cells, equine monocytes. These findings represent a significant advance in our understanding of the fundamental mechanisms associated with the entry of EAV into susceptible cells. PMID:26764004

  12. Degradation of Japanese encephalitis virus by neutrophils

    Science.gov (United States)

    SRIVASTAVA, SONILIKA; KHANNA, NIVEDITA; SAXENA, S K; SINGH, ADITI; MATHUR, ASHA; DHOLE, T N

    1999-01-01

    The ability of neutrophils to degrade the phagocytosed Japanese encephalitis (JE) virion, via triggering of the respiratory burst and generation of toxic radicals has been investigated. JEV or JEV-induced macrophage derived factor (MDF) induces increase in intracellular oxidative signals with generation of superoxide anion (O−2), via activation of cytosolic NADPH and subsequent formation of hydrogen peroxide, with maximum activity on day 7 post infection. The response was sensitive to anti-MDF antibody treatment. Further, the study revealed rapid degradation of phagocytosed JE viral protein and nucleic acid. The viral protein degradation was partially dependent on the generation of toxic oxygen species as it could be abrogated by pretreatment of the cells with staurosporine. PMID:10365083

  13. Epstein-Barr Virus Encephalitis in an Immunocompetent Child: A Case Report and Management of Epstein-Barr Virus Encephalitis

    Directory of Open Access Journals (Sweden)

    Gulsen Akkoc

    2016-01-01

    Full Text Available Epstein-Barr virus (EBV usually causes mild, asymptomatic, and self-limited infections in children and adults; however, it may occasionally lead to severe conditions such as neurological diseases, malignant diseases, hepatic failure, and myocarditis. Epstein-Barr virus-related neurological disorders include meningitis, encephalitis, and cranial or peripheral neuritis, which are mostly seen in immunocompromised patients. The therapeutic modalities for EBV-related severe organ damage including central nervous system manifestations are still uncertain. Herein, we describe a seven-year-old boy with EBV encephalitis who presented with prolonged fever, exudative pharyngitis, reduced consciousness, and neck stiffness. Cranial magnetic resonance imaging showed contrast enhancement in the bilateral insular cortex and the right hypothalamus. The diagnosis was made by EBV-DNA amplification in both the blood and cerebrospinal fluid samples. He was discharged with acyclovir therapy without any sequelae.

  14. Subclinical infection without encephalitis in mice following intranasal exposure to Nipah virus-Malaysia and Nipah virus-Bangladesh

    OpenAIRE

    Dups, Johanna; Middleton, Deborah; Long, Fenella; Arkinstall, Rachel; Glenn A Marsh; Wang, Lin-Fa

    2014-01-01

    Background Nipah virus and Hendra virus are closely related and following natural or experimental exposure induce similar clinical disease. In humans, encephalitis is the most serious outcome of infection and, hitherto, research into the pathogenesis of henipavirus encephalitis has been limited by the lack of a suitable model. Recently we reported a wild-type mouse model of Hendra virus (HeV) encephalitis that should facilitate detailed investigations of its neuropathogenesis, including mecha...

  15. Evolution of equine influenza virus in vaccinated horses.

    Science.gov (United States)

    Murcia, Pablo R; Baillie, Gregory J; Stack, J Conrad; Jervis, Carley; Elton, Debra; Mumford, Jennifer A; Daly, Janet; Kellam, Paul; Grenfell, Bryan T; Holmes, Edward C; Wood, James L N

    2013-04-01

    Influenza A viruses are characterized by their ability to evade host immunity, even in vaccinated individuals. To determine how prior immunity shapes viral diversity in vivo, we studied the intra- and interhost evolution of equine influenza virus in vaccinated horses. Although the level and structure of genetic diversity were similar to those in naïve horses, intrahost bottlenecks may be more stringent in vaccinated animals, and mutations shared among horses often fall close to putative antigenic sites.

  16. Evolution of Equine Influenza Virus in Vaccinated Horses

    Science.gov (United States)

    Murcia, Pablo R.; Baillie, Gregory J.; Stack, J. Conrad; Jervis, Carley; Elton, Debra; Mumford, Jennifer A.; Daly, Janet; Kellam, Paul; Grenfell, Bryan T.; Holmes, Edward C.

    2013-01-01

    Influenza A viruses are characterized by their ability to evade host immunity, even in vaccinated individuals. To determine how prior immunity shapes viral diversity in vivo, we studied the intra- and interhost evolution of equine influenza virus in vaccinated horses. Although the level and structure of genetic diversity were similar to those in naïve horses, intrahost bottlenecks may be more stringent in vaccinated animals, and mutations shared among horses often fall close to putative antigenic sites. PMID:23388708

  17. Epidemiological modeling and risk analysis of Venezuelan Equine Encephalitis in the human population of Coastal Chiapas, Mexico in 2007-2009

    Science.gov (United States)

    Analysis of 101 febrile illness patients sero positive for Venezuelan equine encephalitis (VEEV) was carried out in a retrospective study along 18 municipalities and endemic VEEV pacific coastal regions of the State of Chiapas in southern Mexico. Geographic information systems (GIS), satellite imag...

  18. Neuronal apoptosis in herpes simplex virus - 1 encephalitis (HSE).

    Science.gov (United States)

    Athmanathan, S; Vydehi, B V; Sundaram, C; Vemuganti, G K; Murthy, J M

    2001-01-01

    Herpes simplex virus infections are encountered often due to their ubiquitous nature. Common sites involved include skin, mucous membrane, genitalia, eye and the nervous system. HSV infection of the central nervous system can be life threatening. Little is known about the pathogenesis of this cataclysmic disease, at the cellular level. Virus induced apoptosis may play a role in the molecular pathogenesis of encephalitis. This study aims to detect the presence of apoptosis: a) In the brain tissue obtained at autopsy from a patient who succumbed to Herpes simplex virus - 1 encephalitis (HSE) and b) In a human glioblastoma cell line (SNB 19). Wedge tissue samples were obtained from the inferior surface of the frontal lobe and fixed in buffered formalin. Tissue sections were stained with haematoxylin and eosin for histopathological analysis. An indirect immunoperoxidase assay was performed for the detection of HSV -1 antigen in the tissue sections. Apoptosis in the brain tissue was detected employing the TUNEL assay (Terminal deoxynucleotidyl Transferase (TdT) mediated deoxy Uridine Triphosphate Nick End Labeling) using a commerically available kit (TdT Fragel DNA fragmentation detection kit, Oncogene Research Products, CA). HSV-1 induced apoptosis of SNB 19 cells were detected in-vitro by: a) Membrane blebbing assay and b) Hoechst 33258 staining. Classical features of viral encephalitis including the presence of intranuclear inclusions, neuronal loss and perivascular cuffing were seen in the tissue sections. The immunoperoxidase assay revealed the presence of abundant viral antigen in the neurons, microglial and satellite cells. TUNEL assay revealed many apoptotic neurons, microglial and satellite cells. In-vitro assays showed evidence of HSV-1 induced apoptosis in the SNB 19 cell line. These results suggest that virus induced apoptosis may play a role in the molecular pathogenesis of HSE. Further studies are warranted to elucidate the role of HSV-1 induced apoptosis

  19. Vectors expressing chimeric Japanese encephalitis dengue 2 viruses.

    Science.gov (United States)

    Wei, Y; Wang, S; Wang, X

    2014-01-01

    Vectors based on self-replicating RNAs (replicons) of flaviviruses are becoming powerful tool for expression of heterologous genes in mammalian cells and development of novel antiviral and anticancer vaccines. We constructed two vectors expressing chimeric viruses consisting of attenuated SA14-14-2 strain of Japanese encephalitis virus (JEV) in which the PrM/M-E genes were replaced fully or partially with those of dengue 2 virus (DENV-2). These vectors, named pJED2 and pJED2-1770 were transfected to BHK-21 cells and produced chimeric viruses JED2V and JED2-1770V, respectively. The chimeric viruses could be passaged in C6/36 but not BHK-21 cells. The chimeric viruses produced in C6/36 cells CPE 4-5 days after infection and RT-PCR, sequencing, immunofluorescence assay (IFA) and Western blot analysis confirmed the chimeric nature of produced viruses. The immunogenicity of chimeric viruses in mice was proved by detecting DENV-2 E protein-specific serum IgG antibodies with neutralization titer of 10. Successful preparation of infectious clones of chimeric JEV-DENV-2 viruses showed that JEV-based expression vectors are fully functional.

  20. A new model for Hendra virus encephalitis in the mouse.

    Directory of Open Access Journals (Sweden)

    Johanna Dups

    Full Text Available Hendra virus (HeV infection in humans is characterized by an influenza like illness, which may progress to pneumonia or encephalitis and lead to death. The pathogenesis of HeV infection is poorly understood, and the lack of a mouse model has limited the opportunities for pathogenetic research. In this project we reassessed the role of mice as an animal model for HeV infection and found that mice are susceptible to HeV infection after intranasal exposure, with aged mice reliably developing encephalitic disease. We propose an anterograde route of neuroinvasion to the brain, possibly along olfactory nerves. This is supported by evidence for the development of encephalitis in the absence of viremia and the sequential distribution of viral antigen along pathways of olfaction in the brain of intranasally challenged animals. In our studies mice developed transient lower respiratory tract infection without progressing to viremia and systemic vasculitis that is common to other animal models. These studies report a new animal model of HeV encephalitis that will allow more detailed studies of the neuropathogenesis of HeV infection, particularly the mode of viral spread and possible sequestration within the central nervous system; investigation of mechanisms that moderate the development of viremia and systemic disease; and inform the development of improved treatment options for human patients.

  1. Susceptibility of Peruvian Mosquitoes to Eastern Equine Encephalitis virus

    Science.gov (United States)

    2008-07-01

    Von Humboldt). Voucher specimens were placed in the collection at the National Museum of Natural History, Smithsonian Institution, Washington, DC...Entomology, Walter Reed Army Institute of Research) for identifying the voucher specimens , K. Kenyon for critical reading of the manuscript, and M. Wooster, K...suscep- tible to infection, even when they were exposed to a low viremia, and the only specimen with a dissemi- nated infection that refed

  2. St. Louis encephalitis virus possibly transmitted through blood transfusion-Arizona, 2015.

    Science.gov (United States)

    Venkat, Heather; Adams, Laura; Sunenshine, Rebecca; Krow-Lucal, Elisabeth; Levy, Craig; Kafenbaum, Tammy; Sylvester, Tammy; Smith, Kirk; Townsend, John; Dosmann, Melissa; Kamel, Hany; Patron, Roberto; Kuehnert, Matthew; Annambhotla, Pallavi; Basavaraju, Sridhar V; Rabe, Ingrid B

    2017-12-01

    St. Louis encephalitis virus is a mosquito-borne flavivirus that infrequently causes epidemic central nervous system infections. In the United States, blood donors are not screened for St. Louis encephalitis virus infection, and transmission through blood transfusion has not been reported. During September 2015, St. Louis encephalitis virus infection was confirmed in an Arizona kidney transplant recipient. An investigation was initiated to determine the infection source. The patient was interviewed, and medical records were reviewed. To determine the likelihood of mosquito-borne infection, mosquito surveillance data collected at patient and blood donor residences in timeframes consistent with their possible exposure periods were reviewed. To investigate other routes of exposure, organ and blood donor and recipient specimens were obtained and tested for evidence of St. Louis encephalitis virus infection. The patient presented with symptoms of central nervous system infection. Recent St. Louis encephalitis virus infection was serologically confirmed. The organ donor and three other organ recipients showed no laboratory or clinical evidence of St. Louis encephalitis virus infection. Among four donors of blood products received by the patient via transfusion, one donor had a serologically confirmed, recent St. Louis encephalitis virus infection. Exposure to an infected mosquito was unlikely based on the patient's minimal outdoor exposure. In addition, no St. Louis encephalitis virus-infected mosquito pools were identified around the patient's residence. This investigation provides evidence of the first reported possible case of St. Louis encephalitis virus transmission through blood product transfusion. Health care providers and public health professionals should maintain heightened awareness for St. Louis encephalitis virus transmission through blood transfusion in settings where outbreaks are identified. © 2017 AABB.

  3. Phylogeography of Japanese encephalitis virus: genotype is associated with climate.

    Directory of Open Access Journals (Sweden)

    Amy J Schuh

    Full Text Available The circulation of vector-borne zoonotic viruses is largely determined by the overlap in the geographical distributions of virus-competent vectors and reservoir hosts. What is less clear are the factors influencing the distribution of virus-specific lineages. Japanese encephalitis virus (JEV is the most important etiologic agent of epidemic encephalitis worldwide, and is primarily maintained between vertebrate reservoir hosts (avian and swine and culicine mosquitoes. There are five genotypes of JEV: GI-V. In recent years, GI has displaced GIII as the dominant JEV genotype and GV has re-emerged after almost 60 years of undetected virus circulation. JEV is found throughout most of Asia, extending from maritime Siberia in the north to Australia in the south, and as far as Pakistan to the west and Saipan to the east. Transmission of JEV in temperate zones is epidemic with the majority of cases occurring in summer months, while transmission in tropical zones is endemic and occurs year-round at lower rates. To test the hypothesis that viruses circulating in these two geographical zones are genetically distinct, we applied Bayesian phylogeographic, categorical data analysis and phylogeny-trait association test techniques to the largest JEV dataset compiled to date, representing the envelope (E gene of 487 isolates collected from 12 countries over 75 years. We demonstrated that GIII and the recently emerged GI-b are temperate genotypes likely maintained year-round in northern latitudes, while GI-a and GII are tropical genotypes likely maintained primarily through mosquito-avian and mosquito-swine transmission cycles. This study represents a new paradigm directly linking viral molecular evolution and climate.

  4. Nipah virus: an emergent paramyxovirus causing severe encephalitis in humans.

    Science.gov (United States)

    Bellini, William J; Harcourt, Brian H; Bowden, Nadine; Rota, Paul A

    2005-10-01

    Nipah virus is a recently emergent paramyxovirus that is capable of causing severe disease in both humans and animals. The first outbreak of Nipah virus occurred in Malaysia and Singapore in 1999 and, more recently, outbreaks were detected in Bangladesh. In humans, Nipah virus causes febrile encephalitis with respiratory syndrome that has a high mortality rate. The reservoir for Nipah virus is believed to be fruit bats, and humans are infected by contact with infected bats or by contact with an intermediate animal host such as pigs. Person to person spread of the virus has also been described. Nipah virus retains many of the genetic and biologic properties found in other paramyxoviruses, though it also has several unique characteristics. However, the virologic characteristics that allow the virus to cause severe disease over a broad host range, and the epidemiologic, environmental and virologic features that favor transmission to humans are unknown. This review summarizes what is known about the virology, epidemiology, pathology, diagnosis and control of this novel pathogen.

  5. Sensitivity of Toxorhynchites amboinensis mosquitoes versus chicken embryonic cell cultures for assays of Venezuelan encephalitis virus.

    Science.gov (United States)

    Scherer, W F; Chin, J

    1981-05-01

    Toxorhynchites amboinensis mosquitoes inoculated intrathoracically with Venezuelan encephalitis virus and tested for infectious virus 12 to 19 days later by inoculation of primary chicken embryonic cell cultures yielded approximately the same titers of virus as did direct inoculation of cultures, with counting of plaques 3 days thereafter. Titers were slightly higher in T. amboinensis for three virus strains, equal for two virus strains, and slightly lower for two virus strains. Comparative titers of four strains were similar, whether virus suspensions came from infectious vertebrate cells or infected invertebrate (T. amboinensis) cells. Each of the seven strains of Venezuelan encephalitis virus reached virus concentrations of 10(4.2) to 10(5.1) plaque-forming units in individual T. amboinensis mosquitoes after extrinsic incubation periods of 12 to 19 days. No temperature-sensitive (29 versus 37 degrees C) virus was detected in T. amboinensis mosquitoes infected by six strains of Venezuelan encephalitis virus.

  6. Isolation of Saint Louis Encephalitis Virus from a Horse with Neurological Disease in Brazil

    Science.gov (United States)

    Rosa, Roberta; Costa, Erica Azevedo; Marques, Rafael Elias; Oliveira, Taismara Simas; Furtini, Ronaldo; Bomfim, Maria Rosa Quaresma; Teixeira, Mauro Martins; Paixão, Tatiane Alves; Santos, Renato Lima

    2013-01-01

    St. Louis encephalitis virus (SLEV) is a causative agent of encephalitis in humans in the Western hemisphere. SLEV is a positive-sense RNA virus that belongs to the Flavivirus genus, which includes West Nile encephalitis virus, Japanese encephalitis virus, Dengue virus and other medically important viruses. Recently, we isolated a SLEV strain from the brain of a horse with neurological signs in the countryside of Minas Gerais, Brazil. The SLEV isolation was confirmed by reverse-transcription RT-PCR and sequencing of the E protein gene. Virus identity was also confirmed by indirect immunofluorescence using commercial antibodies against SLEV. To characterize this newly isolated strain in vivo, serial passages in newborn mice were performed and led to hemorrhagic manifestations associated with recruitment of inflammatory cells into the central nervous system of newborns. In summary this is the first isolation of SLEV from a horse with neurological signs in Brazil. PMID:24278489

  7. Surto de encefalomielite equina Leste na Ilha de Marajó, Pará Eastern equine encephalitis on Marajó Island, Pará state, Brazil

    Directory of Open Access Journals (Sweden)

    Karinny F. Campos

    2013-04-01

    Full Text Available Nove casos de encefalomielite equina foram estudados na Ilha de Marajó, estado do Pará, Brasil. Os equinos apresentavam dificuldade em se manter em estação, andavam em círculo, tinham acentuada depressão, pálpebras cerradas, paralisia da língua, tremores musculares, bruxismo, anorexia e desidratação. Alguns apresentavam diminuição dos reflexos auricular, palpebral, de ameaça, diminuição do tônus da língua e taquicardia. Posição de auto-auscultação foi observada com frequência. Os animais muitas vezes eram encontrados apoiados em troncos e cercas para se manterem em estação. À necropsia verificou-se hemorragia das leptomeninges e da medula, alguns apresentaram ainda aderência das leptomeninges. À histopatologia verificou-se encefalite difusa que afetava principalmente a substância cinzenta, com meningite e coroidite. Foi observada perivasculite mononuclear. Em dois equinos identificou-se o vírus da encefalomielite equina Leste pela reação de Semi-Nested transcrição reversa de polimerase em cadeia (Semi-Nested RT-PCR.Nine cases of equine encephalomyelitis on Marajó Island, state of Pará, Brazil, were studied. The affected horses had difficulty to stand, walked in circles, with marked depression, closed eyelids, tongue paralysis, muscle tremors, bruxism, anorexia and dehydration. Some had their ear and eyelid reflexes diminished, decreased tongue tone and tachycardia; laid down frequently they kept their head on the chest. Often they were seen resting their head on tree trunks or fences. At necropsy, hemorrhages of the meninges and spinal cord, and in some animals also adhesion of the meninges were found. Histologically there was diffuse encephalitis affecting mainly the gray matter, with meningitis and choroiditis. Presence of perivascular cuffs consisting of mononuclear inflammatory cells was observed. From two horses the Eastern equine encephalitis virus was identified by semi-nested reverse transcription

  8. The effects of equine rhinovirus, influenza virus and herpesvirus infection on tracheal clearance rate in horses.

    OpenAIRE

    Willoughby, R; Ecker, G.; McKee, S; Riddolls, L; Vernaillen, C; Dubovi, E; Lein, D; Mahony, J B; Chernesky, M; Nagy, E.

    1992-01-01

    The response of horses exposed to three common respiratory viruses was studied by measuring tracheal mucociliary clearance rates in the trachea. Tracheal clearance rates (TCR) were determined before, during illness and following recovery in horses exposed to equine rhinovirus (ERhV-2), equine influenza virus (EIV) and equine herpesvirus (EHV-4) by means of lateral scintigraphs made following an injection of technetium-99m sulphide colloid into the tracheal lumen. In six horses exposed to ERhV...

  9. Detection of West Nile Virus and other common equine viruses in three locations from the Leeward Islands, West Indies.

    Science.gov (United States)

    Bolfa, Pompei; Jeon, Isaac; Loftis, Amanda; Leslie, Teresa; Marchi, Silvia; Sithole, Fortune; Beck, Cecile; Lecollinet, Sylvie; Zientara, Stephan; Hans, Aymeric; Issel, Charles J

    2017-10-01

    Equines in the West Indies are used for recreational purposes, tourism industry, racing and agriculture or can be found in feral populations. Little is known in the Caribbean basin about the prevalence of some major equine infectious diseases, some with zoonotic potential, listed as reportable by the OIE. Our objective was to study the prevalence of antibodies for West Nile Virus (WNV), Equine Herpes Virus-1 and 4 (EHV-1 and EHV-4), Equine Influenza (EI), Equine Viral Arteritis (EVA) and Equine Infectious Anemia Virus (EIAV) using a retrospective serological convenience study. We used 180 equine serum samples, 140 from horses and 40 from donkeys in St. Kitts, Nevis, and Sint Eustatius, collected between 2006 and 2015 that were tested with ELISA kits and virus neutralization (for WNV and EVA). Combining ELISA with virus neutralization testing, 25 (13.8%) equine sera were WNV positive (a mixture of indigenous and imported equines) and 3 sera (1.6%) showed doubtful results. For EHV-1, 41 equines (23.7%), mean age 6.7 years, were seropositive. For EHV-4, 138 equines were found seropositive (82.8%), mean age 6.3 years. For EI, 49 equines (27.2%), mean age 7.5 years, were seropositive on ELISA, some previously vaccinated horses. No antibodies against EAV were found on virus neutralization testing, although one animal (0.6%), was EAV positive on ELISA. All samples were EIAV negative. The seroprevalence for EHV-1 and EHV-4 is similar to other parts of the world. For the first time in the study location serologic evidence of antibodies against WNV and EI is reported. This was found in both indigenous and imported animals, highlighting the need for developing proper surveillance plans based on complementary methods of virus detection. Further studies will be needed to define the prevalence, rates of transmission, characterize local virus strains, and study their impact on these populations. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Sequential MRI, SPECT and PET in respiratory syncytial virus encephalitis

    Energy Technology Data Exchange (ETDEWEB)

    Hirayama, K.; Sakazaki, Hiromi; Murakami, Seiko; Yonezawa, Sumiko [Department of Paediatrics, Izumi Municipal Hospital, Osaka (Japan); Fujimoto, Keiji [Dept. of Radiology, Izumi Municipal Hospital, Osaka (Japan); Seto, Toshiyuki; Tanaka, Katsuji; Hattori, Hideji; Matsuoka, Osamu [Dept. of Paediatrics, Osaka City University Medical School, Osaka (Japan); Murata, Ryosuke [Children`s Medical Centre, Osaka City General Hospital, Osaka (Japan)

    1999-04-01

    We report on a 3-year-old girl with respiratory syncytial virus (RSV) encephalitis manifested by disturbance of consciousness, conjugate eye deviation, anuria, truncal ataxia and intention tremor. T2-weighted magnetic resonance imaging (MRI) showed hyperintense areas in the cerebellar cortex. No lesion was detected in the cerebral cortex, pons or spinal cord. The hyperintense areas in the cerebellar cortex diminished with recovery from the clinical manifestations and had resolved 2 months after onset. The MRI lesions in the cerebellum were considered to be due to oedema. SPECT and positron emission tomography (PET), performed 3 months after onset, disclosed areas of hypoperfusion and hypometabolism at the same sites. One year after onset, MRI showed mild atrophy of the cerebellum. Hypoperfusion on SPECT and hypometabolism on PET remained. Neuroimaging showed that ataxia and tremor in this case were the result of cerebellitis. The patient has no neurological deficit except for mild truncal ataxia. This patient is a rare example of RSV encephalitis. (orig.) With 4 figs., 16 refs.

  11. Crystal Structure of the Japanese Encephalitis Virus Envelope Protein

    Energy Technology Data Exchange (ETDEWEB)

    Luca, Vincent C.; AbiMansour, Jad; Nelson, Christopher A.; Fremont, Daved H. (WU-MED)

    2012-03-13

    Japanese encephalitis virus (JEV) is the leading global cause of viral encephalitis. The JEV envelope protein (E) facilitates cellular attachment and membrane fusion and is the primary target of neutralizing antibodies. We have determined the 2.1-{angstrom} resolution crystal structure of the JEV E ectodomain refolded from bacterial inclusion bodies. The E protein possesses the three domains characteristic of flavivirus envelopes and epitope mapping of neutralizing antibodies onto the structure reveals determinants that correspond to the domain I lateral ridge, fusion loop, domain III lateral ridge, and domain I-II hinge. While monomeric in solution, JEV E assembles as an antiparallel dimer in the crystal lattice organized in a highly similar fashion as seen in cryo-electron microscopy models of mature flavivirus virions. The dimer interface, however, is remarkably small and lacks many of the domain II contacts observed in other flavivirus E homodimers. In addition, uniquely conserved histidines within the JEV serocomplex suggest that pH-mediated structural transitions may be aided by lateral interactions outside the dimer interface in the icosahedral virion. Our results suggest that variation in dimer structure and stability may significantly influence the assembly, receptor interaction, and uncoating of virions.

  12. Purpura fulminans associated with acute West Nile virus encephalitis.

    Science.gov (United States)

    Shah, Sheevam; Fite, Laura Paul; Lane, Natalie; Parekh, Palak

    2016-02-01

    Purpura fulminans is a progressive thrombotic disorder that presents with widespread purpura due to deficiency or dysfunction of protein C or protein S. Lesions present as well-demarcated erythematous macules that progress to irregular areas of hemorrhagic necrosis.West Nile virus is a member of the Flaviviridae family transmitted to humans through the bite of various mosquito species. It manifests as West Nile fever in 25% of those infected and less commonly as neuroinvasive disease. An African American man in his fortiespresented with altered mental status and was noted to have evidence of disseminated intravascular coagulation according to his lab data. He then developed dusky skin discoloration and systemic flaccid bullae with desquamation. Biopsy was consistent with purpura fulminans and the patient eventually developed symmetric peripheral gangrene, requiring amputations of all four extremities. Infectious work up revealed positive testing for IgM and IgG antibodies in serum and cerebrospinal fluid leading to the diagnosis of acute West Nile Virus encephalitis. We present this case to describe the rarely reported association of purpura fulminans with West Nile Virus infection. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. West Nile virus encephalitis induced opsoclonus-myoclonus syndrome

    Directory of Open Access Journals (Sweden)

    Chad J. Cooper

    2014-04-01

    Full Text Available West Nile virus (WNV is an arthropod borne neurotropic single stranded RNA flavivirus with <1% developing presenting with neurological disease. Immunocompromised and elderly patients are more prone to developing WNV meningitis or encephalitis. Definitive diagnosis of WNV meningoencephalitis is a combination of clinical suspicion and cerebrospinal fluid (CSF serology. Forty-eight year old Caucasian female presented with a sudden onset of altered mental status after being found unresponsive. She was confused with intermittent bouts of alertness/lethargy and unintelligible responses to questioning. Her medical problems included endometrial cancer that was in remission after undergoing a total abdominal hysterectomy with bilateral salpingectomy and postoperative chemotherapy with paclitaxel and carboplatin. Pertinent physical examination revealed muscle strength that was significantly decreased, nuchal rigidity and +2 pitting edema of both lower extremities. Computed tomography and magnetic resonance imaging of the brain were negative for any intracranial pathology. CSF analysis was consistent with aseptic meningitis with all CSF serology being negative except for positive WNV antibody. A few days after being admitted she developed involuntary random movements of her eyes and generalized jerking movements (myoclonus. This was determined to be opsoclonus myoclonus syndrome (OMS induced by the WNV meningoencephalitis. She then received five consecutive days of plasmapheresis with a significant improvement in her neurological status. Opsoclonusmyoclonus syndrome (OMS is a rare neurological disorder associated with chaotic multidirectional eye movements, myoclonus and less frequently cerebellar ataxia. OMS affects as few as 1 in 10,000,000 people per year. The pathogenesis is not fully understood with the majority of cases of opsoclonus-myoclonus syndrome being idiopathic. According to current medical literature there have only been two previous case

  14. Interactions of human microglia cells with Japanese encephalitis virus.

    Science.gov (United States)

    Lannes, Nils; Neuhaus, Viviane; Scolari, Brigitte; Kharoubi-Hess, Solange; Walch, Michael; Summerfield, Artur; Filgueira, Luis

    2017-01-14

    Japanese encephalitis virus (JEV) is a neurotropic flavivirus causing mortality and morbidity in humans. Severe Japanese encephalitis cases display strong inflammatory responses in the central nervous system and an accumulation of viral particles in specific brain regions. Microglia cells are the unique brain-resident immune cell population with potent migratory functions and have been proposed to act as a viral reservoir for JEV. Animal models suggest that the targeting of microglia by JEV is partially responsible for inflammatory reactions in the brain. Nevertheless, the interactions between human microglia and JEV are poorly documented. Using human primary microglia and a new model of human blood monocyte-derived microglia, the present study explores the interaction between human microglia and JEV as well as the role of these cells in viral transmission to susceptible cells. To achieve this work, vaccine-containing inactivated JEV and two live JEV strains were applied on human microglia. Live JEV was non-cytopathogenic to human microglia but increased levels of CCL2, CXCL9 and CXCL10 in such cultures. Furthermore, human microglia up-regulated the expression of the fraktalkine receptor CX3CR1 upon exposure to both JEV vaccine and live JEV. Although JEV vaccine enhanced MHC class II on all microglia, live JEV enhanced MHC class II mainly on CX3CR1+ microglia cells. Importantly, human microglia supported JEV replication, but infectivity was only transmitted to neighbouring cells in a contact-dependent manner. Our findings suggest that human microglia may be a source of neuronal infection and sustain JEV brain pathogenesis.

  15. Immunogenicity of the Inactivated Japanese Encephalitis Virus Vaccine IXIARO in Children From a Japanese Encephalitis Virus-endemic Region.

    Science.gov (United States)

    Dubischar, Katrin L; Kadlecek, Vera; Sablan, Jr Benjamin; Borja-Tabora, Charissa Fay; Gatchalian, Salvacion; Eder-Lingelbach, Susanne; Kiermayr, Sigrid; Spruth, Martin; Westritschnig, Kerstin

    2017-09-01

    Japanese encephalitis (JE) is a major public health concern in Asia and poses a small but potentially fatal threat to travelers from nonendemic countries, including children. No JE vaccine for pediatric use has been available in Europe and the United States. Age-stratified cohorts of children between 2 months and 17 years received 2 doses of Vero cell-derived inactivated JE virus vaccine (IXIARO; Valneva Austria GmbH, Vienna, Austria) administered 28 days apart [half adult dose); ≥3 years, 0.5 mL (full adult dose)]. Immunogenicity endpoints were seroconversion rate, 4-fold increase in JE neutralizing antibody titer and geometric mean titer assessed 56 days and 7 months after the first vaccination in 496 subjects of the intent-to-treat population. The immune response to JE virus at both time points was also analyzed according to prevaccination JE virus and dengue virus serostatus. At day 56, seroconversion was attained in ≥99.2% of subjects with age-appropriate dosing, 4-fold increases in titer were reported for 77.4%-100% in various age groups, and geometric mean titers ranged from 176 to 687, with younger children having the strongest immune response. At month 7, seroconversion was maintained in 85.5%-100% of subjects. Pre-existing JE virus immunity did not impact on immune response at day 56; however, it led to a better persistence of protective antibody titers at month 7. IXIARO is highly immunogenic at both doses tested in the pediatric population, leading to protective antibody titers at day 56 in >99% of subjects who received the age-appropriate dose.

  16. Phylogenetic characterisation of the G(L) sequences of equine arteritis virus isolated from semen of asymptomatic stallions and fatal cases of equine viral arteritis in Denmark

    DEFF Research Database (Denmark)

    Larsen, Lars Erik; Storgaard, Torben; Holm, Elisabeth

    2001-01-01

    The study describes for the first time the phylogenetic relationship between equine arteritis virus (EAV) isolated from asymptomatic virus-shedding stallions and fatal cases of equine viral arteritis (EVA) in an European country. EAV was isolated from three dead foals and an aborted foetus during...

  17. Developing GIS-based eastern equine encephalitis vector-host models in Tuskegee, Alabama

    Directory of Open Access Journals (Sweden)

    Novak Robert J

    2010-02-01

    Full Text Available Abstract Background A site near Tuskegee, Alabama was examined for vector-host activities of eastern equine encephalomyelitis virus (EEEV. Land cover maps of the study site were created in ArcInfo 9.2® from QuickBird data encompassing visible and near-infrared (NIR band information (0.45 to 0.72 μm acquired July 15, 2008. Georeferenced mosquito and bird sampling sites, and their associated land cover attributes from the study site, were overlaid onto the satellite data. SAS 9.1.4® was used to explore univariate statistics and to generate regression models using the field and remote-sampled mosquito and bird data. Regression models indicated that Culex erracticus and Northern Cardinals were the most abundant mosquito and bird species, respectively. Spatial linear prediction models were then generated in Geostatistical Analyst Extension of ArcGIS 9.2®. Additionally, a model of the study site was generated, based on a Digital Elevation Model (DEM, using ArcScene extension of ArcGIS 9.2®. Results For total mosquito count data, a first-order trend ordinary kriging process was fitted to the semivariogram at a partial sill of 5.041 km, nugget of 6.325 km, lag size of 7.076 km, and range of 31.43 km, using 12 lags. For total adult Cx. erracticus count, a first-order trend ordinary kriging process was fitted to the semivariogram at a partial sill of 5.764 km, nugget of 6.114 km, lag size of 7.472 km, and range of 32.62 km, using 12 lags. For the total bird count data, a first-order trend ordinary kriging process was fitted to the semivariogram at a partial sill of 4.998 km, nugget of 5.413 km, lag size of 7.549 km and range of 35.27 km, using 12 lags. For the Northern Cardinal count data, a first-order trend ordinary kriging process was fitted to the semivariogram at a partial sill of 6.387 km, nugget of 5.935 km, lag size of 8.549 km and a range of 41.38 km, using 12 lags. Results of the DEM analyses indicated a statistically significant inverse

  18. Encephalitis

    Science.gov (United States)

    ... occur through: Breathing in droplets from the nose, mouth, or throat from an infected person Contaminated food or drink Mosquito, tick, and other insect bites Skin contact Different viruses occur in different ...

  19. Japanese encephalitis virus vaccine candidates generated by chimerization with dengue virus type 4.

    Science.gov (United States)

    Gromowski, Gregory D; Firestone, Cai-Yen; Hanson, Christopher T; Whitehead, Stephen S

    2014-05-23

    Japanese encephalitis virus (JEV) is a leading cause of viral encephalitis worldwide and vaccination is one of the most effective ways to prevent disease. A suitable live-attenuated JEV vaccine could be formulated with a live-attenuated tetravalent dengue vaccine for the control of these viruses in endemic areas. Toward this goal, we generated chimeric virus vaccine candidates by replacing the precursor membrane (prM) and envelope (E) protein structural genes of recombinant dengue virus type 4 (rDEN4) or attenuated vaccine candidate rDEN4Δ30 with those of wild-type JEV strain India/78. Mutations were engineered in E, NS3 and NS4B protein genes to improve replication in Vero cells. The chimeric viruses were attenuated in mice and some elicited modest but protective levels of immunity after a single dose. One particular chimeric virus, bearing E protein mutation Q264H, replicated to higher titer in tissue culture and was significantly more immunogenic in mice. The results are compared with live-attenuated JEV vaccine strain SA14-14-2. Published by Elsevier Ltd.

  20. Risk of exposure to eastern equine encephalomyelitis virus increases with the density of northern cardinals.

    Directory of Open Access Journals (Sweden)

    Laura K Estep

    Full Text Available For a variety of infectious diseases, the richness of the community of potential host species has emerged as an important factor in pathogen transmission, whereby a higher richness of host species is associated with a lowered disease risk. The proposed mechanism driving this pattern is an increased likelihood in species-rich communities that infectious individuals will encounter dead-end hosts. Mosquito-borne pathogen systems potentially are exceptions to such "dilution effects" because mosquitoes vary their rates of use of vertebrate host species as bloodmeal sources relative to host availabilities. Such preferences may violate basic assumptions underlying the hypothesis of a dilution effect in pathogen systems. Here, we describe development of a model to predict exposure risk of sentinel chickens to eastern equine encephalitis virus (EEEV in Walton County, Florida between 2009 and 2010 using avian species richness as well as densities of individual host species potentially important to EEEV transmission as candidate predictor variables. We found the highest support for the model that included the density of northern cardinals, a highly preferred host of mosquito vectors of EEEV, as a predictor variable. The highest-ranking model also included Culiseta melanura abundance as a predictor variable. These results suggest that mosquito preferences for vertebrate hosts influence pathogen transmission.

  1. Identification of equine influenza virus infection in Asian wild horses (Equus przewalskii).

    Science.gov (United States)

    Yin, Xin; Lu, Gang; Guo, Wei; Qi, Ting; Ma, Jian; Zhu, Chao; Zhao, Shihua; Pan, Jialiang; Xiang, Wenhua

    2014-05-01

    An outbreak of equine influenza was observed in the Asian wild horse population in Xinjiang Province, China, in 2007. Nasal swabs were collected from wild horses and inoculated into 9-10-day SPF embryonated eggs. The complete genome of the isolate was sequenced. A comparison of the amino acid sequence revealed that the isolate was an equine influenza virus strain, which we named A/equine/Xinjiang/4/2007. Each gene of the virus was found to have greater than 99 % homology to equine influenza virus strains of the Florida-2 sublineage, which were circulating simultaneously in China, and a lesser amount of homology was found to the strain A/equine/Qinghai/1/1994 (European lineage), which was isolated during the last outbreak in China. These observations were confirmed by phylogenetic analysis. In addition, the deduced amino acid sequence of the neuraminidase of the A/equine/Xinjiang/4/2007 strain was identical to that of A/equine/California/8560/2002, an American isolate, and was found to be similar to those of Florida-2 strains found in other countries by comparing them with nine other field strains that were isolated in China from 2007 to 2008. It is suggested that the neuraminidase segment of A/equine/Xinjiang/4/2007 may have been obtained from equine influenza virus strains from other countries. We report for the first time an outbreak of equine influenza in the Asian wild horse population, and the complete genome of the virus is provided and analyzed.

  2. The genetics of virus particle shape in equine influenza A virus.

    Science.gov (United States)

    Elton, Debra; Bruce, Emily A; Bryant, Neil; Wise, Helen M; MacRae, Shona; Rash, Adam; Smith, Nikki; Turnbull, Matthew L; Medcalf, Liz; Daly, Janet M; Digard, Paul

    2013-12-01

    Many human strains of influenza A virus produce highly pleomorphic virus particles that at the extremes can be approximated as either spheres of around 100 nm diameter or filaments of similar cross-section but elongated to lengths of many microns. The role filamentous virions play in the virus life cycle remains enigmatic. Here, we set out to define the morphology and genetics of virus particle shape in equine influenza A virus, using reverse genetics and microscopy of infected cells. The majority of H3N8 strains tested were found to produce filamentous virions, as did the prototype H7N7 A/eq/Prague/56 strain. The exception was the prototype H3N8 isolate, A/eq/Miami/63. Reassortment of equine influenza virus M genes from filamentous and non-filamentous strains into the non-filamentous human virus A/PR/8/34 confirmed that segment 7 is a major determinant of particle shape. Sequence analysis identified three M1 amino acid polymorphisms plausibly associated with determining virion morphology, and the introduction of these changes into viruses confirmed the importance of two: S85N and N231D. However, while either change alone affected filament production, the greatest effect was seen when the polymorphisms were introduced in conjunction. Thus, influenza A viruses from equine hosts also produce filamentous virions, and the major genetic determinants are set by the M1 protein. However, the precise sequence determinants are different to those previously identified in human or porcine viruses. © 2013 Blackwell Publishing Ltd.

  3. A protective chimeric antibody to tick-borne encephalitis virus.

    Science.gov (United States)

    Baykov, Ivan K; Matveev, Andrey L; Stronin, Oleg V; Ryzhikov, Alexander B; Matveev, Leonid E; Kasakin, Marat F; Richter, Vladimir A; Tikunova, Nina V

    2014-06-17

    The efficiency of several mouse monoclonal antibodies (mAbs) specific to the tick-borne encephalitis virus (TBEV) glycoprotein E in post-exposure prophylaxis was assessed, and mAb14D5 was shown to be the most active of all those studied. It was proven that the hybridoma cell line 14D5 produced one immunoglobulin H chain and two L chains. They were used to construct chimeric antibodies ch14D5a and ch14D5b, the affinity constants of which were 2.6 × 10(10)M(-1) and 1.0 × 10(7)M(-1), respectively, according to the SPR-based ProteOn biosensor assay. The neutralization index (IC50) of ch14D5a was 0.04 μg/ml in the focus reduction neutralization test. In in vivo experiments, ch14D5a at a dose of 10 μg/mouse resulted in a 100% survival of the mice infected with 240 LD50 of TBEV. This chimeric antibody is promising for further development of prevention and therapeutic drugs against TBEV. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. DC-SIGN Increases Japanese Encephalitis Virus Infection

    Directory of Open Access Journals (Sweden)

    Yang Yang, Ali Zohaib, Gong Chen, Jing Ye and Shengbo Cao*

    2013-11-01

    Full Text Available Japanese Encephalitis virus (JEV is a mosquito borne flavivirus that infects macrophages, monocytes and dendritic cells (DCs during in vivo replication. The C-type lectins DC-SIGN and DC-SIGNR have been reported to act as cell attachment factors for diverse array of pathogens. In this study, the effect of these lectins on JEV infection was investigated after the generation of 293T-SIGN (R cell lines expressing DC-SIGN and DC-SIGNR receptors. It was observed that only DC-SIGN but not the DC-SIGNR can act as a viral attachment factor in case of JEV infection. The infection to cells expressing DC-SIGN was efficiently blocked by anti-DC-SIGN and mannan molecules. It was also found that insect derived JEV has higher affinity for DC-SIGN as compare to the mammalian derived JEV. These results initially suggest that DC-SIGN could act as viral attachment receptors (VAR for JEV and enhance JEV infection.

  5. Toward Viral Vaccine Development: A Modified Venezuelan Equine Encephalitis Replicon as Strategy for Optimizing Immunogenicity

    Science.gov (United States)

    2007-04-13

    Morrissy, J. White, and B. T. Eaton. 2002. A rapid immune plaque assay for the detection of Hendra and Nipah viruses and anti- virus antibodies. J...HIV-1 envelope glycoprotein and to the fusion (F) and attachment (G) glycoproteins of two zoonotic pathogens, Hendra and Nipah viruses , in a murine...VII. Henipaviruses Introduction: Henipavirus is a genus of the family Paramyxoviridae, order Mononegavirales containing two members, Hendra virus

  6. [DETECTION OF VENEZUELAN EQUINE ENCEPHALOMYELITIS VIRUS RNA IN BIOLOGICAL SAMPLES BY REVERSE-TRANSCRIPTION POLYMERASE CHAIN REACTION].

    Science.gov (United States)

    Petrov, A A; Pyshnaya, N S; Lebedev, V N; Kulish, V S; Stovba, L F; Kazantsev, A V; Borisevich, S V

    2015-01-01

    Detection-and identification of Venezuelan equine encephalomyelitis (VEE) virus RNA in biological samples by reverse-transcription polymerase chain reaction (RT-PCR) and RT-PCR in real time (rRT-PCR). VEE, Sindbis, West Nile, Japanese and tick-borne encephalitis viruses were studied. Cell culture of chicken fibroblasts, outbred mice and rats, Javanese macaques were used in the experiments. Biological activity determination of the running culture of causative agents used in the experiments was carried out by negative colony method in monolayer cell culture under agar coating. and using intra-cerebral infection of mice. Reagent kits developed in the 48th Central Research Institute and Institute of Analytical Instrument Engineering were used during execution of experiments of VEE virus RNA detection by RT-PCR and rRT-PCR. VEE virus was detected in biological samples by various methods. Data from RT-PCR and rRT-PCR are in accordance with the results of virus detection in samples using sensitive animals. Use of molecular-diagnostics methods for detection in biological samples of a causative agent of a dangerous infectious disease is important for procuring biological safety of Russian Federation.

  7. Development of a peptide ELISA for the diagnosis of Equine arteritis virus

    OpenAIRE

    Metz, German Ernesto; Lorenzon, Esteban Nicolás; Serena, Maria Soledad; Corva, Santiago Gerardo; Panei, Carlos Javier; Diaz, Silvina; Maffud Cilli, Eduardo; Echeverria, Maria Gabriela

    2017-01-01

    A peptide-based indirect ELISA was developed to detect antibodies against Equine arteritis virus (EAV). Two peptides for epitope C of protein GP5 and fragment E of protein M were designed, synthesized, purified and used as antigens either alone or combined. Ninety-two serum samples obtained from the 2010 Equine viral arteritis outbreak, analyzed previously by virus neutralization, were evaluated by the ELISA here developed. The best resolution was obtained using peptide GP5. The analysis of t...

  8. Quantification of vector and host competence and abundance for Japanese Encephalitis Virus: a systematic review of the literature.

    Science.gov (United States)

    Japanese encephalitis (JE) is a vector-borne disease caused by the Japanese encephalitis virus (JEV) that affects humans in Eastern and Southeastern Asia. Although it could be prevented by a vaccine, JE has no treatment and the inadvertent introduction of the virus into JEV-free countries, such as t...

  9. A systematic review of the literature to identify and quantify host and vector competence and abundance of Japanese Encephalitis Virus

    Science.gov (United States)

    Japanese Encephalitis virus (JEV) is a mosquito-borne arbovirus that causes endemic and epidemic encephalitis in Eastern and Southeastern Asia. Swine and wading birds serve as reservoirs for the virus, which can be transmitted to humans via mosquitos. Currently, there is no specific treatment availa...

  10. Eastern equine encephalitis (EEE): a description of the 1989 outbreak, recent epidemiologic trends, and the association of rainfall with EEE occurrence.

    Science.gov (United States)

    Letson, G W; Bailey, R E; Pearson, J; Tsai, T F

    1993-12-01

    An Eastern equine encephalitis (EEE) outbreak in 1989 led to nine human and 196 equine cases, chiefly in coastal Atlantic and Gulf Coast counties. In the past two decades, EEE age-specific incidence and mortality rates have declined compared with earlier years. Analysis of rainfall patterns in areas where human EEE cases occurred between 1983 and 1989 revealed an association between occurrence of human cases and excess rainfall. The association was stronger with data from local weather stations than from statewide rainfall averages and the predictive models were best when applied to northern states. The sensitivity and specificity of these measures varied, depending on the model used, but the positive predictive value was no better than 50%, regardless of the rainfall model applied.

  11. [Susceptibility of Aedes albopictus and Culex pipiens quinquefasciatus to infection with bat Japanese encephalitis virus isolates].

    Science.gov (United States)

    Liu, Shan; Zhang, Qionghua; Zhou, Junhua; Yu, Shouyi; Zheng, Xueli; Chen, Qing

    2012-04-01

    To evaluate the susceptibility of Aedes albopictus and Culex pipiens quinquefasciatus to oral infection with bat Japanese encephalitis virus isolates (GD1 and HN2 strains). Aedes albopictus and Culex pipiens quinquefasciatus were infected orally by GD1 and HN2 strains of bat Japanese encephalitis virus. TaqMan real-time PCR was used to detect the virus and monitor the changes in the viral loads in Aedes albopictus and Culex pipiens quinquefasciatus at a 2-day interval, starting from 4 days till 20 days after the infection. The infected Aedes albopictus and Culex pipiens quinquefasciatus were found positive for the Japanese encephalitis virus from day 4 to day 20. Both Aedes albopictus and Culex pipiens quinquefasciatus were susceptible to infection by GD1 and HN2 strains, but the latter showed a greater susceptibility. The HN2 strain virus appeared to have a greater virulence than the GD1 strain. Aedes albopictus and Culex pipiens quinquefasciatus can carry GD1 and HN2 strains of bat Japanese encephalitis virus isolates.

  12. [Nonstructural protein 1 of tick-borne encephalitis virus activates the expression of immunoproteasome subunits].

    Science.gov (United States)

    Kuzmenko, Y V; Starodubova, E S; Karganova, G G; Timofeev, A V; Karpov, V L

    2016-01-01

    The interaction of viral proteins with host cell components plays an important role in antiviral immune response. One of the key steps of antiviral defense is the formation of immunoproteasomes. The effect of nonstructural protein 1 (NS1) of tick-borne encephalitis virus on the immunoproteasome formation was studied. It was shown that cell expression of NS1 does not reduce the efficacy of the immunoproteasome generation in response to interferon-γ stimulation and even increases the content of the immunoproteasome subunits without the interferon-γ treatment. Thus, NS1 of tick-borne encephalitis virus activates, rather than blocks the mechanisms of immune defense in the cell.

  13. Chikungunya virus infection amongst the acute encephalitis syndrome cases in West Bengal, India

    Directory of Open Access Journals (Sweden)

    D Taraphdar

    2015-01-01

    Full Text Available Chikungunya virus (CHIKV infection from the acute encephalitis syndrome cases is an uncommon form and has been observed in the year 2010-11 from West Bengal, India. The case-1 and case-2 had the acute encephalitis syndrome; case-3 was of acute disseminated encephalomyelitis whereas the case-4 had the symptoms of meningo-encephalopathy with bulbar involvement. We are reporting four cases with neurological complications involving central nervous system (CNS due to CHIKV infection from this state for the first time. The virus has spread almost every districts of this state rapidly. At this stage, these cases are public health threat.

  14. Subclinical infection without encephalitis in mice following intranasal exposure to Nipah virus-Malaysia and Nipah virus-Bangladesh.

    Science.gov (United States)

    Dups, Johanna; Middleton, Deborah; Long, Fenella; Arkinstall, Rachel; Marsh, Glenn A; Wang, Lin-Fa

    2014-06-02

    Nipah virus and Hendra virus are closely related and following natural or experimental exposure induce similar clinical disease. In humans, encephalitis is the most serious outcome of infection and, hitherto, research into the pathogenesis of henipavirus encephalitis has been limited by the lack of a suitable model. Recently we reported a wild-type mouse model of Hendra virus (HeV) encephalitis that should facilitate detailed investigations of its neuropathogenesis, including mechanisms of disease recrudescence. In this study we investigated the possibility of developing a similar model of Nipah virus encephalitis. Aged and young adult wild type mice did not develop clinical disease including encephalitis following intranasal exposure to either the Malaysia (NiV-MY) or Bangladesh (NiV-BD) strains of Nipah virus. However viral RNA was detected in lung tissue of mice at euthanasia (21 days following exposure) accompanied by a non-neutralizing antibody response. In a subsequent time course trial this viral RNA was shown to be reflective of an earlier self-limiting and subclinical lower respiratory tract infection through successful virus re-isolation and antigen detection in lung. There was no evidence for viremia or infection of other organs, including brain. Mice develop a subclinical self-limiting lower respiratory tract infection but not encephalitis following intranasal exposure to NiV-BD or NiV-MY. These results contrast with those reported for HeV under similar exposure conditions in mice, demonstrating a significant biological difference in host clinical response to exposure with these viruses. This finding provides a new platform from which to explore the viral and/or host factors that determine the neuroinvasive ability of henipaviruses.

  15. Effects of weather and landscape on the equine West Nile virus infection risk in Mississippi, USA

    Directory of Open Access Journals (Sweden)

    Guiming Wang

    2015-11-01

    Full Text Available The West Nile virus (WNv continues to be a public health concern in North America. Dry weather appears to increase human WNv infection risks, but it is uncertain whether dry weather conditions exert similar effects on the corresponding equine WNv infection. This study assessed the effects of precipitation of the previous year and land cover diversity on the equine WNv risk of Mississippi, USA, at the county level in the year 2002 using Bayesian hierarchical models. The risk estimated for 2002 was found to be inversely related to annual precipitation of the preceding year. Equine WNv risks were lower with greater land cover diversity probably due to the diluting effects of biodiversity. Correlation between the equine and human WNv risks was positive but relatively low. Dry weather conditions of the previous year might reduce mosquito competitors and predators and subsequently increase mosquito abundances and equine WNv risks in agricultural areas with low biodiversity.

  16. Focal Coxsackie virus B5 encephalitis with synchronous seizure cluster and eruption: Infantile case.

    Science.gov (United States)

    Shiohama, Tadashi; Omata, Taku; Muta, Kaori; Kodama, Kazuo; Fujii, Katsunori; Shimojo, Naoki

    2016-05-01

    Enterovirus focal encephalitis is a rare clinical entity that is characterized by focal neurological signs including seizure, hemiparesis, hemichorea, and headache, which are mainly followed by rapid spontaneous improvement. We herein describe the case of a 9-month-old boy who developed Coxsackie virus B5 (CVB5) focal encephalitis with seizure clusters in the eruption stage of roseola infantum-like illness, which were followed by rapid improvement and benign outcome. Lumbar puncture indicated pleocytosis, and CVB5 infection in the cerebrospinal fluid was subsequently identified on genome sequencing and virus isolation. Magnetic resonance imaging and electroencephalography showed no abnormal findings at the acute stage or on 2 month follow up. Although the pathogenesis of enterovirus focal encephalitis currently remains unclear, the pure synchronism of seizure cluster and eruption in this case suggests the involvement of local vascular impairment as the underlying pathogenesis. © 2015 Japan Pediatric Society.

  17. Characterization and Pathogenesis of Aerosolized Eastern Equine Encephalitis in the Common Marmoset (Callithrix jacchus)

    Science.gov (United States)

    2016-08-10

    Klimstra, W.B. 2014. RNA viruses can hijack vertebrate 642 microRNAs to suppress innate immunity . Nature. 506, 245-248. 643 TR-16-143 DISTRIBUTION...countermeasures. 37 Key words 38 Animal model, alphavirus, immunity , nonhuman primate, pathogenesis 39 TR-16-143 DISTRIBUTION STATEMENT A: Approved...pathological changes (Reed, 2007). We describe the differential effects of dose on 83 the immune cell populations in the blood, blood chemistry, viral

  18. Relation of genetic phylogeny and geographical distance of tick-borne encephalitis virus in central Europe

    NARCIS (Netherlands)

    Weidmann, M.; Ruzek, D.; Krivanec, K.; Zoeller, G.; Essbauer, S.; Pfeffer, M.; Zanotto, P. M. de A.; Hufert, F. T.; Dobler, G.

    Tick-borne encephalitis virus (TBEV) is the most important arboviral agent causing disease of the central nervous system in central Europe. In this study, 61 TBEV E gene sequences derived from 48 isolates from the Czech Republic, and four isolates and nine TBEV strains detected in ticks from

  19. Production of Japanese Encephalitis Virus Antigens in Plants Using Bamboo Mosaic Virus-Based Vector

    Directory of Open Access Journals (Sweden)

    Tsung-Hsien Chen

    2017-05-01

    Full Text Available Japanese encephalitis virus (JEV is among the major threats to public health in Asia. For disease control and prevention, the efficient production of safe and effective vaccines against JEV is in urgent need. In this study, we produced a plant-made JEV vaccine candidate using a chimeric virus particle (CVP strategy based on bamboo mosaic virus (BaMV for epitope presentation. The chimeric virus, designated BJ2A, was constructed by fusing JEV envelope protein domain III (EDIII at the N-terminus of BaMV coat protein, with an insertion of the foot-and-mouth disease virus 2A peptide to facilitate the production of both unfused and epitope-presenting for efficient assembly of the CVP vaccine candidate. The strategy allowed stable maintenance of the fusion construct over long-term serial passages in plants. Immuno-electron microscopy examination and immunization assays revealed that BJ2A is able to present the EDIII epitope on the surface of the CVPs, which stimulated effective neutralizing antibodies against JEV infection in mice. This study demonstrates the efficient production of an effective CVP vaccine candidate against JEV in plants by the BaMV-based epitope presentation system.

  20. Production of Japanese Encephalitis Virus Antigens in Plants Using Bamboo Mosaic Virus-Based Vector.

    Science.gov (United States)

    Chen, Tsung-Hsien; Hu, Chung-Chi; Liao, Jia-Teh; Lee, Yi-Ling; Huang, Ying-Wen; Lin, Na-Sheng; Lin, Yi-Ling; Hsu, Yau-Heiu

    2017-01-01

    Japanese encephalitis virus (JEV) is among the major threats to public health in Asia. For disease control and prevention, the efficient production of safe and effective vaccines against JEV is in urgent need. In this study, we produced a plant-made JEV vaccine candidate using a chimeric virus particle (CVP) strategy based on bamboo mosaic virus (BaMV) for epitope presentation. The chimeric virus, designated BJ2A, was constructed by fusing JEV envelope protein domain III (EDIII) at the N-terminus of BaMV coat protein, with an insertion of the foot-and-mouth disease virus 2A peptide to facilitate the production of both unfused and epitope-presenting for efficient assembly of the CVP vaccine candidate. The strategy allowed stable maintenance of the fusion construct over long-term serial passages in plants. Immuno-electron microscopy examination and immunization assays revealed that BJ2A is able to present the EDIII epitope on the surface of the CVPs, which stimulated effective neutralizing antibodies against JEV infection in mice. This study demonstrates the efficient production of an effective CVP vaccine candidate against JEV in plants by the BaMV-based epitope presentation system.

  1. [F-18]FHPG positron emission tomography for detection of herpes simplex virus (HSV) in experimental HSV encephalitis

    NARCIS (Netherlands)

    Buursma, AR; de Vries, EFJ; Garssen, J; Kegler, D; van Waarde, A; Schirm, J; Hospers, GAP; Mulder, NH; Vaalburg, W; Klein, HC

    Herpes simplex virus type 1 (HSV-1) is one of the most common causes of sporadic encephalitis. The initial clinical course of HSV encephalitis (HSE) is highly variable, and the infection may be rapidly fatal. For effective treatment with antiviral medication, an early diagnosis of HSE is crucial.

  2. Emergence or improved detection of Japanese encephalitis virus in the Himalayan highlands?

    Science.gov (United States)

    Baylis, Matthew; Barker, Christopher M; Caminade, Cyril; Joshi, Bhoj R; Pant, Ganesh R; Rayamajhi, Ajit; Reisen, William K; Impoinvil, Daniel E

    2016-04-01

    The emergence of Japanese encephalitis virus (JEV) in the Himalayan highlands is of significant veterinary and public health concern and may be related to climate warming and anthropogenic landscape change, or simply improved surveillance. To investigate this phenomenon, a One Health approach focusing on the phylogeography of JEV, the distribution and abundance of the mosquito vectors, and seroprevalence in humans and animal reservoirs would be useful to understand the epidemiology of Japanese encephalitis in highland areas. © The Author 2016. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.

  3. Molecular identification of Saint Louis encephalitis virus genotype IV in Colombia

    Directory of Open Access Journals (Sweden)

    Richard Hoyos-López

    2015-09-01

    Full Text Available Saint Louis encephalitis virus (SLEV is a member of the Japanese-encephalitis virus serocomplex of the genus Flavivirus. SLEV is broadly distributed in the Americas and the Caribbean Islands, where it is usually transmitted by mosquitoes of the genus Culex and primarily to birds and mammalian-hosts. Humans are occasionally infected by the virus and are dead-end hosts. SLEV causes encephalitis in temperate regions, while in tropical regions of the Americas, several human cases and a wide biological diversity of SLEV-strains have been reported. The phylogenetic analysis of the envelope (E protein genes indicated eight-genotypes of SLEV with geographic overlap. The present paper describes the genotyping of two SLEV viruses detected in mosquito-pools collected in northern Colombia (department of Cordoba. We used reverse transcription-polymerase chain reaction to amplify a fragment of theE-gene to confirm the virus identity and completeE-gene sequencing for phylogenetic analysis and genotyping of the two-SLEV viruses found circulating in Córdoba. This is the first report of SLEV genotype IV in Colombia (Córdoba in mosquitoes from a region of human inhabitation, implicating the risk of human disease due to SLEV infection. Physicians should consider SLEV as a possible aetiology for undiagnosed febrile and neurologic syndromes among their patients who report exposure to mosquito-bites.

  4. PREVALENCE OF ANTIBODIES AGAINST INFLUENZA VIRUS IN NON-VACCINATED EQUINES FROM THE BRAZILIAN PANTANAL

    Directory of Open Access Journals (Sweden)

    Lucas Gaíva E Silva

    2014-12-01

    Full Text Available The prevalence of antibodies against Equine Influenza Virus (EIV was determined in 529 equines living on ranches in the municipality of Poconé, Pantanal area of Brazil, by means of the hemagglutination inhibition test, using subtype H3N8 as antigen. The distribution and possible association among positive animal and ranches were evaluated by the chi-square test, spatial autoregressive and multiple linear regression models. The prevalence of antibodies against EIV was estimated at 45.2% (95% CI 30.2 - 61.1% with titers ranging from 20 to 1,280 HAU. Seropositive equines were found on 92.0% of the surveyed ranches. Equine from non-flooded ranches (66.5% and negativity in equine infectious anemia virus (EIAV (61.7% were associated with antibodies against EIV. No spatial correlation was found among the ranches, but the ones located in non-flooded areas were associated with antibodies against EIV. A negative correlation was found between the prevalence of antibodies against EIV and the presence of EIAV positive animals on the ranches. The high prevalence of antibodies against EIV detected in this study suggests that the virus is circulating among the animals, and this statistical analysis indicates that the movement and aggregation of animals are factors associated to the transmission of the virus in the region.

  5. PREVALENCE OF ANTIBODIES AGAINST INFLUENZA VIRUS IN NON-VACCINATED EQUINES FROM THE BRAZILIAN PANTANAL

    Science.gov (United States)

    Silva, Lucas Gaíva E; Borges, Alice Mamede Costa Marques; Villalobos, Eliana Monteforte Cassaro; Lara, Maria do Carmo Custodio Souza Hunold; Cunha, Elenice Maria Siquetin; de Oliveira, Anderson Castro Soares; Braga, Ísis Assis; Aguiar, Daniel Moura

    2014-01-01

    The prevalence of antibodies against Equine Influenza Virus (EIV) was determined in 529 equines living on ranches in the municipality of Poconé, Pantanal area of Brazil, by means of the hemagglutination inhibition test, using subtype H3N8 as antigen. The distribution and possible association among positive animal and ranches were evaluated by the chi-square test, spatial autoregressive and multiple linear regression models. The prevalence of antibodies against EIV was estimated at 45.2% (95% CI 30.2 - 61.1%) with titers ranging from 20 to 1,280 HAU. Seropositive equines were found on 92.0% of the surveyed ranches. Equine from non-flooded ranches (66.5%) and negativity in equine infectious anemia virus (EIAV) (61.7%) were associated with antibodies against EIV. No spatial correlation was found among the ranches, but the ones located in non-flooded areas were associated with antibodies against EIV. A negative correlation was found between the prevalence of antibodies against EIV and the presence of EIAV positive animals on the ranches. The high prevalence of antibodies against EIV detected in this study suggests that the virus is circulating among the animals, and this statistical analysis indicates that the movement and aggregation of animals are factors associated to the transmission of the virus in the region. PMID:25351542

  6. Delayed IFN response differentiates replication of West Nile virus and Japanese encephalitis virus in human neuroblastoma and glioblastoma cells.

    Science.gov (United States)

    Takamatsu, Yuki; Uchida, Leo; Morita, Kouichi

    2015-08-01

    West Nile virus (WNV) and Japanese encephalitis virus (JEV) are important causes of human encephalitis cases, which result in a high mortality ratio and neurological sequelae after recovery. Understanding the mechanism of neuropathogenicity in these viral infections is important for the development of specific antiviral therapy. Here, we focused on human-derived neuronal and glial cells to understand the cellular responses against WNV and JEV infection. It was demonstrated that early IFN-β induction regulated virus replication in glioblastoma tbl98G cells, whereas delayed IFN-β induction resulted in efficient virus replication in neuroblastoma SK-N-SH cells. Moreover, the concealing of viral dsRNA in the intracellular membrane resulted in the delayed IFN response in SK-N-SH cells. These results, which showed different IFN responses between human neuronal and glial cells after WNV or JEV infection, are expected to contribute to our understanding of the molecular mechanisms for neuropathology in these viral infections.

  7. Respiratory syncytial virus-related encephalitis: magnetic resonance imaging findings with diffusion-weighted study

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    Park, Arim; Suh, Sang-il; Seol, Hae-Young [Korea University College of Medicine, Department of Radiology, Korea University Guro Hospital, Seoul (Korea, Republic of); Son, Gyu-Ri; Lee, Nam-Joon [Korea University College of Medicine, Department of Radiology, Korea University Anam Hospital, Seoul (Korea, Republic of); Lee, Young Hen; Seo, Hyung Suk [Korea University College of Medicine, Department of Radiology, Korea University Ansan Hospital, Gyeonggi-do (Korea, Republic of); Eun, Baik-Lin [Korea University College of Medicine, Department of Pediatrics, Korea University Guro Hospital, Seoul (Korea, Republic of)

    2014-02-15

    Respiratory syncytial virus (RSV) is a common pathogen causing acute respiratory infection in children. Herein, we describe the incidence and clinical and magnetic resonance imaging (MRI) findings of RSV-related encephalitis, a major neurological complication of RSV infection. We retrospectively reviewed the medical records and imaging findings of the patients over the past 7 years who are admitted to our medical center and are tested positive for RSV-RNA by reverse transcriptase PCR. In total, 3,856 patients were diagnosed with RSV bronchiolitis, and 28 of them underwent brain MRI for the evaluation of neurologic symptoms; 8 of these 28 patients had positive imaging findings. Five of these 8 patients were excluded because of non-RSV-related pathologies, such as subdural hemorrhage, brain volume loss due to status epilepticus, periventricular leukomalacia, preexisting ventriculomegaly, and hypoxic brain injury. The incidence of RSV-related encephalitis was as follows: 3/3,856 (0.08 %) of the patients are positive for RSV RNA, 3/28 (10.7 %) of the patient underwent brain MRI for neurological symptom, and 3/8 (37.5 %) of patients revealed abnormal MR findings. The imaging findings were suggestive of patterns of rhombenmesencephalitis, encephalitis with acute disseminated encephalomyelitis, and limbic encephalitis. They demonstrated no diffusion abnormality on diffusion-weighted image and symptom improvement on the follow-up study. Encephalitis with RSV bronchiolitis occurs rarely. However, on brain MRI performed upon suspicion of neurologic involvement, RSV encephalitis is not infrequently observed among the abnormal MR findings and may mimic other viral and limbic encephalitis. Physicians should be aware of this entity to ensure proper diagnosis and neurologic care of RSV-positive patients. (orig.)

  8. First Isolation of West Nile virus from a patient with encephalitis in the United States.

    Science.gov (United States)

    Huang, Cinnia; Slater, Brett; Rudd, Robert; Parchuri, Nandakishore; Hull, Rene; Dupuis, Michelle; Hindenburg, Alexander

    2002-12-01

    West Nile virus (WNV) was isolated from a patient who developed encephalitis while undergoing treatment with CHOP (cyclophosphamide, hydroxydoxorubicin, vincristine [Oncovin], predisone) and rituximab for a non-Hodgkin B-cell lymphoma. Both standard reverse transcription-polymerase chain reaction (RT-PCR) and Taqman RT-PCR established the diagnosis of WNV infection from cerebrospinal fluid (CSF). Several whole blood samples and one serum sample underwent further testing. CSF and serum samples were negative for WNV antibody; however, all samples were positive by both RT-PCR assays. Infectious virus was recovered from a blood sample, and its identity was confirmed by using a WNV-specific immunofluorescence assay. The complete WNV genomes determined from CSF and from the virus isolate adapted from cell culture were the same. The results represent the first complete WNV genome sequence obtained directly from human CSF and the first time that infectious WNV has been recovered from a patient with encephalitis in North America.

  9. Tick-borne encephalitis virus - a review of an emerging zoonosis.

    Science.gov (United States)

    Mansfield, K L; Johnson, N; Phipps, L P; Stephenson, J R; Fooks, A R; Solomon, T

    2009-08-01

    During the last 30 years, there has been a continued increase in human cases of tick-borne encephalitis (TBE) in Europe, a disease caused by tick-borne encephalitis virus (TBEV). TBEV is endemic in an area ranging from northern China and Japan, through far-eastern Russia to Europe, and is maintained in cycles involving Ixodid ticks (Ixodes ricinus and Ixodes persulcatus) and wild vertebrate hosts. The virus causes a potentially fatal neurological infection, with thousands of cases reported annually throughout Europe. TBE has a significant mortality rate depending upon the strain of virus or may cause long-term neurological/neuropsychiatric sequelae in people affected. In this review, we comprehensively reviewed TBEV, its epidemiology and pathogenesis, the clinical manifestations of TBE, along with vaccination and prevention. We also discuss the factors which may have influenced an apparent increase in the number of reported human cases each year, despite the availability of effective vaccines.

  10. Estimating the burden of Japanese encephalitis virus and other encephalitides in countries of the mekong region.

    Directory of Open Access Journals (Sweden)

    Arnaud Tarantola

    Full Text Available Diverse aetiologies of viral and bacterial encephalitis are widely recognized as significant yet neglected public health issues in the Mekong region. A robust analysis of the corresponding health burden is lacking. We retrieved 75 articles on encephalitis in the region published in English or in French from 1965 through 2011. Review of available data demonstrated that they are sparse and often derived from hospital-based studies with significant recruitment bias. Almost half (35 of 75 of articles were on Japanese encephalitis virus (JEV alone or associated with dengue. In the Western Pacific region the WHO reported 30,000-50,000 annual JEV cases (15,000 deaths between 1966 and 1996 and 4,633 cases (200 deaths in 2008, a decline likely related to the introduction of JEV vaccination in China, Vietnam, or Thailand since the 1980s. Data on dengue, scrub typhus and rabies encephalitis, among other aetiologies, are also reviewed and discussed. Countries of the Mekong region are undergoing profound demographic, economic and ecological change. As the epidemiological aspects of Japanese encephalitis (JE are transformed by vaccination in some countries, highly integrated expert collaborative research and objective data are needed to identify and prioritize the human health, animal health and economic burden due to JE and other pathogens associated with encephalitides.

  11. Estimating the Burden of Japanese Encephalitis Virus and Other Encephalitides in Countries of the Mekong Region

    Science.gov (United States)

    Tarantola, Arnaud; Goutard, Flavie; Newton, Paul; de Lamballerie, Xavier; Lortholary, Olivier; Cappelle, Julien; Buchy, Philippe

    2014-01-01

    Diverse aetiologies of viral and bacterial encephalitis are widely recognized as significant yet neglected public health issues in the Mekong region. A robust analysis of the corresponding health burden is lacking. We retrieved 75 articles on encephalitis in the region published in English or in French from 1965 through 2011. Review of available data demonstrated that they are sparse and often derived from hospital-based studies with significant recruitment bias. Almost half (35 of 75) of articles were on Japanese encephalitis virus (JEV) alone or associated with dengue. In the Western Pacific region the WHO reported 30,000–50,000 annual JEV cases (15,000 deaths) between 1966 and 1996 and 4,633 cases (200 deaths) in 2008, a decline likely related to the introduction of JEV vaccination in China, Vietnam, or Thailand since the 1980s. Data on dengue, scrub typhus and rabies encephalitis, among other aetiologies, are also reviewed and discussed. Countries of the Mekong region are undergoing profound demographic, economic and ecological change. As the epidemiological aspects of Japanese encephalitis (JE) are transformed by vaccination in some countries, highly integrated expert collaborative research and objective data are needed to identify and prioritize the human health, animal health and economic burden due to JE and other pathogens associated with encephalitides. PMID:24498443

  12. BK virus encephalitis: case report, review of the literature, and description of a novel treatment modality.

    Science.gov (United States)

    Chittick, Paul; Williamson, John C; Ohl, Christopher A

    2013-09-01

    To describe a case of BK virus encephalitis with attempted direct antiviral therapy, review the reported cases of BK virus in the central nervous system, and report the novel use of intravenous cimetidine in place of oral probenecid to minimize the toxicities of intravenous cidofovir. A 36-year-old male with acute myelomonocytic leukemia and subsequent myelodysplastic syndrome underwent allogeneic hematopoietic stem cell transplant. His course was complicated by severe graft-versus-host disease involving his skin and gastrointestinal tract. Five weeks after transplantation, he developed fever and confusion. Magnetic resonance imaging was suggestive of limbic encephalitis and cerebrospinal fluid tested positive for BK virus. Therapy with intravenous cidofovir was thought to be indicated. Although probenecid is commonly used to minimize the toxicities of cidofovir, the patient's severe graft-versus-host disease raised concerns about absorption of oral medications. Based on animal models and pharmacokinetic data, intravenous cimetidine was used in place of oral probenecid. Despite these therapies, the patient's mental status did not improve. He developed progressive organ system failure, and care was ultimately withdrawn. BK virus is increasingly described as a cause of encephalitis. The majority of reported cases have occurred in immunocompromised patients and have generally had a poor outcome. This case describes attempted antiviral therapy using cidofovir, the antiviral agent used most frequently in other syndromes due to BK virus. Intravenous cimetidine is a novel modality used to minimize ocular and renal toxicities frequently seen with cidofovir, and we believe this warrants further investigation. BK virus may be a cause of encephalitis in immunocompromised hosts, and cidofovir represents a possible treatment option. Intravenous cimetidine can be considered to minimize toxicities associated with cidofovir use in patients unable to tolerate or absorb oral

  13. Nonstructural Protein L* Species Specificity Supports a Mouse Origin for Vilyuisk Human Encephalitis Virus.

    Science.gov (United States)

    Drappier, Melissa; Opperdoes, Fred R; Michiels, Thomas

    2017-07-15

    Vilyuisk human encephalitis virus (VHEV) is a picornavirus related to Theiler's murine encephalomyelitis virus (TMEV). VHEV was isolated from human material passaged in mice. Whether this VHEV is of human or mouse origin is therefore unclear. We took advantage of the species-specific activity of the nonstructural L* protein of theiloviruses to track the origin of TMEV isolates. TMEV L* inhibits RNase L, the effector enzyme of the interferon pathway. By using coimmunoprecipitation and functional RNase L assays, the species specificity of RNase L antagonism was tested for L* from mouse (DA) and rat (RTV-1) TMEV strains as well as for VHEV. Coimmunoprecipitation and functional assay data confirmed the species specificity of L* activity and showed that L* from rat strain RTV-1 inhibited rat but not mouse or human RNase L. Next, we showed that the VHEV L* protein was phylogenetically related to L* of mouse viruses and that it failed to inhibit human RNase L but readily antagonized mouse RNase L, unambiguously showing the mouse origin of VHEV. IMPORTANCE Defining the natural host of a virus can be a thorny issue, especially when the virus was isolated only once or when the isolation story is complex. The species Theilovirus includes Theiler's murine encephalomyelitis virus (TMEV), infecting mice and rats, and Saffold virus (SAFV), infecting humans. One TMEV strain, Vilyuisk human encephalitis virus (VHEV), however, was isolated from mice that were inoculated with cerebrospinal fluid of a patient presenting with chronic encephalitis. It is therefore unclear whether VHEV was derived from the human sample or from the inoculated mouse. The L* protein encoded by TMEV inhibits RNase L, a cellular enzyme involved in innate immunity, in a species-specific manner. Using binding and functional assays, we show that this species specificity even allows discrimination between TMEV strains of mouse and of rat origins. The VHEV L* protein clearly inhibited mouse but not human RNase L

  14. Herpes Simplex Virus-1 Encephalitis in Adults: Pathophysiology, Diagnosis, and Management.

    Science.gov (United States)

    Bradshaw, Michael J; Venkatesan, Arun

    2016-07-01

    Herpetic infections have plagued humanity for thousands of years, but only recently have advances in antiviral medications and supportive treatments equipped physicians to combat the most severe manifestations of disease. Prompt recognition and treatment can be life-saving in the care of patients with herpes simplex-1 virus encephalitis, the most commonly identified cause of sporadic encephalitis worldwide. Clinicians should be able to recognize the clinical signs and symptoms of the infection and familiarize themselves with a rational diagnostic approach and therapeutic modalities, as early recognition and treatment are key to improving outcomes. Clinicians should also be vigilant for the development of acute complications, including cerebral edema and status epilepticus, as well as chronic complications, including the development of autoimmune encephalitis associated with antibodies to the N-methyl-D-aspartate receptor and other neuronal cell surface and synaptic epitopes. Herein, we review the pathophysiology, differential diagnosis, and clinical and radiological features of herpes simplex virus-1 encephalitis in adults, including a discussion of the most common complications and their treatment. While great progress has been made in the treatment of this life-threatening infection, a majority of patients will not return to their previous neurologic baseline, indicating the need for further research efforts aimed at improving the long-term sequelae.

  15. Delayed Diagnosis of Tuberculous Meningitis Misdiagnosed as Herpes Simplex Virus-1 Encephalitis With the FilmArray Syndromic Polymerase Chain Reaction Panel.

    Science.gov (United States)

    Gomez, Carlos A; Pinsky, Benjamin A; Liu, Anne; Banaei, Niaz

    2017-01-01

    The FilmArray meningitis/encephalitis (ME) panel is a novel syndromic, nucleic acid amplification test for diagnosis of acute meningitis and encephalitis. Emerging data on its performance are concerning for false-positive results. We present a case of tuberculous meningitis misdiagnosed as herpes simplex virus-1 encephalitis with the FilmArray ME panel. Strategies to mitigate erroneous results are discussed.

  16. Drug Targets in Infections With Ebola and Marburg Viruses

    Science.gov (United States)

    2009-01-01

    Venezuelan equine encephalitis (VEE) virus -like replicon (VRP), adenovirus 5 (AdS), vesicular stomatitis virus ( VSV )-based vaccines, and virus -like... virus itself may prove to be a very effective way to clear or prevent virus infection, an inherent flaw in this method does exist for several viruses ...immunofluorescence and ELISA. Rab9 siRNA also decreased replication of HIV and measles virus . This was not observed in non~enveloped viruses , which

  17. serologic evidence of equine h7 influenza virus in polo horses in ...

    African Journals Online (AJOL)

    Administrator

    Chen et al., 2006; Normile, 2006; Ducatez et al.,. 2007; Garten et al., 2009; Smith et al., 2009). Further studies are recommended in order to isolate and characterize H7 influenza viruses from equine and avian host species which may prove to be.

  18. Retrospective Analysis of the Equine Influenza Virus A/Equine/Kirgizia/26/1974 (H7N7 Isolated in Central Asia

    Directory of Open Access Journals (Sweden)

    Kobey Karamendin

    2016-08-01

    Full Text Available A retrospective phylogenetic characterization of the hemagglutinin, neuraminidase and nucleoprotein genes of equine influenza virus A/equine/Kirgizia/26/1974 (H7N7 which caused an outbreak in Kirgizia (a former Soviet Union republic, now Kyrgyzstan in 1977 was conducted. It was defined that it was closely related to the strain London/1973 isolated in Europe and it shared a maximum nucleotide sequence identity at 99% with it. This Central Asian equine influenza virus isolate did not have any specific genetic signatures and can be considered as an epizootic strain of 1974 that spread in Europe. The absence of antibodies to this subtype EI virus (EIV in recent research confirms its disappearance as of the 1990s when the antibodies were last found in unvaccinated horses.

  19. Evaluation of reverse-transcriptase PCR as a diagnostic tool to confirm Japanese encephalitis virus infection.

    Science.gov (United States)

    Saxena, Vandana; Mishra, Virendra K; Dhole, Tapan N

    2009-04-01

    Japanese encephalitis (JE) is a serious central nervous system infection and major public health problem in several countries of Southeast Asia including India. This study evaluated the use of IgM ELISA and reverse-transcriptase (RT)-PCR in blood and cerebrospinal fluid (CSF) samples from acute encephalitis patients for the detection of Japanese encephalitis virus (JEV). Forty-four children suffering from acute encephalitis were enrolled, and 36 were selected from whom both CSF and serum samples were available. Twenty-two of the 36 CSF samples were positive for JEV by IgM ELISA and all were negative by RT-PCR. Twenty-three of the 36 serum samples were positive by IgM ELISA while 28 were positive by RT-PCR. Total positivity for JEV infection in CSF and serum samples was 66.7% (24/36) and 83.3% (30/36) respectively by one or both tests. The overall positivity for JEV infection was 86.1% (31/36). We suggest that the use of RT-PCR in serum samples during the early days of JEV infection may be helpful in confirming diagnosis in those cases which are negative for JEV-specific IgM antibodies in both serum and CSF samples.

  20. Viperin restricts Zika virus and tick-borne encephalitis virus replication by targeting NS3 for proteasomal degradation.

    Science.gov (United States)

    Panayiotou, Christakis; Lindqvist, Richard; Kurhade, Chaitanya; Vonderstein, Kirstin; Pasto, Jenny; Edlund, Karin; Upadhyay, Arunkumar S; Överby, Anna K

    2018-01-10

    Flaviviruses are arthropod-borne viruses that constitute a major global health problem, with millions of human infections annually. Their pathogenesis ranges from mild illness to severe manifestations such as hemorrhagic fever and fatal encephalitis. Type I interferons (IFNs) are induced in response to viral infection, and stimulate the expression of interferon-stimulated genes (ISGs), including that encoding viperin (virus-inhibitory protein, endoplasmic reticulum-associated, IFN-inducible), which shows antiviral activity against a broad spectrum of viruses including several flaviviruses. Here we describe a novel antiviral mechanism exerted by viperin against two prominent flaviviruses, tick-borne encephalitis virus (TBEV) and Zika virus (ZIKV). Viperin was found to interact and co-localize with the structural proteins pre-membrane (prM) and envelope (E) of TBEV, as well as the non-structural (NS) proteins NS2A, NS2B, and NS3. Interestingly, viperin expression reduced the NS3 protein level, and the stability of the other interacting viral proteins, but only in the presence of NS3. We also found that although viperin interacted with NS3 of mosquito-borne flaviviruses (ZIKV, Japanese encephalitis virus, and yellow fever virus), only ZIKV was sensitive to the antiviral effect of viperin. This sensitivity correlated with viperin's ability to induce proteasome-dependent degradation of NS3. ZIKV and TBEV replication was rescued completely when NS3 was overexpressed, suggesting that the viral NS3 is the specific target of viperin. In summary, we present here a novel antiviral mechanism of viperin that is selective for specific viruses in the genus Flavivirus, affording the possibility of new drug targets that can be used for therapeutic intervention.ImportanceFlaviviruses are a group of enveloped RNA viruses that cause severe diseases in humans and animals worldwide, but no antiviral treatment is yet available. Viperin, a host protein produced in response to infection

  1. Post Tick-Borne Encephalitis Virus Vaccination Narcolepsy with Cataplexy.

    Science.gov (United States)

    Hidalgo, Hildegard; Kallweit, Ulf; Mathis, Johannes; Bassetti, Claudio L

    2016-10-01

    Narcolepsy with cataplexy (NC) is a chronic neurological disorder thought to result from an altered immune response based on a genetic predisposition coupled with environmental factors. Pandemrix vaccination has been reported to increase the risk of narcolepsy. We aimed at identifying other vaccines associated with the onset of narcolepsy. Case series and retrospective database study. We identified four cases of NC following a tick-borne encephalitis (TBE) vaccination with FSME Immun. Additional four cases could be detected in the database of the Paul-Ehrlich-Institut, Federal Institute for Vaccines and Biomedicines in Germany. Our findings implicate TBE vaccination as a potential additional environmental factor for the development of NC and add additional evidence for an immunological mechanism in the pathogenesis of the disease.

  2. Antibody escape kinetics of equine infectious anemia virus infection of horses.

    Science.gov (United States)

    Schwartz, Elissa J; Nanda, Seema; Mealey, Robert H

    2015-07-01

    Lentivirus escape from neutralizing antibodies (NAbs) is not well understood. In this work, we quantified antibody escape of a lentivirus, using antibody escape data from horses infected with equine infectious anemia virus. We calculated antibody blocking rates of wild-type virus, fitness costs of mutant virus, and growth rates of both viruses. These quantitative kinetic estimates of antibody escape are important for understanding lentiviral control by antibody neutralization and in developing NAb-eliciting vaccine strategies. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  3. [Serological evidence of St. Louis encephalitis virus circulation in birds from Buenos Aires City, Argentina].

    Science.gov (United States)

    Beltrán, Fernando J; Díaz, Luis A; Konigheim, Brenda; Molina, José; Beaudoin, Juan B; Contigiani, Marta; Spinsanti, Lorena I

    2015-01-01

    Our goal was to determine the presence of neutralizing antibodies against St. Louis encephalitis virus (SLEV) and West Nile virus (WNV) in sera of wild and domestic birds from Buenos Aires City, Argentina. From October 2012 to April 2013, 180 samples were collected and processed by the microneutralization technique. A 7.2% of the sampled birds were seropositive for SLEV, while no seropositive birds for WNV were detected. Copyright © 2015 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  4. Increasing evidence of tick-borne encephalitis (TBE) virus transmission, the Netherlands, June 2016.

    Science.gov (United States)

    Weststrate, Adriaan Cg; Knapen, Daan; Laverman, Gozewijn D; Schot, Bart; Prick, Jan Jw; Spit, Silke A; Reimerink, Johan; Rockx, Barry; Geeraedts, Felix

    2017-03-16

    We present a case of endemic tick-borne encephalitis (TBE) occurring in June 2016 in the eastern part of the Netherlands in an area where a strain of TBE virus, genetically different from the common TBE virus strains in Europe, was reported in ticks in 2016. With the start of the tick season in spring, this second autochthonous Dutch TBE case should remind physicians to consider the possibility of endemic TBE in patients with respective symptoms. This article is copyright of The Authors, 2017.

  5. Affinity (tropism) of caprine arthritis encephalitis virus for brain cells

    African Journals Online (AJOL)

    STORAGESEVER

    2008-11-19

    Nov 19, 2008 ... while wobbling gait with ataxia are the main features in goat kids. The virus was first identified in the USA (Cork et al., 1974). To-date, eight .... Nucleotide sequence and transcriptional analysis of molecular clones of CAEV which generate infectious virus. Virology, 179: 347-364. Watkins BA, Dorn HH, Kelly ...

  6. ELA-DRA polymorphisms are not associated with Equine Arteritis Virus infection in horses from Argentina.

    Science.gov (United States)

    Kalemkerian, P B; Metz, G E; Peral-Garcia, P; Echeverria, M G; Giovambattista, G; Díaz, S

    2012-12-01

    Polymorphisms at Major Histocompatibility Complex (MHC) genes have been associated with resistance/susceptibility to infectious diseases in domestic animals. The aim of this investigation was to evaluate whether polymorphisms of the DRA gene the Equine Lymphocyte Antigen is associated with susceptibility to Equine Arteritis Virus (EAV) infection in horses in Argentina. The equine DRA gene was screened for polymorphisms using Pyrosequencing® Technology which allowed the detection of three ELA-DRA exon 2 alleles. Neither allele frequencies nor genotypic differentiation exhibited any statistically significant (P-values=0.788 and 0.745) differences between the EAV-infected and no-infected horses. Fisher's exact test and OR calculations did not show any significant association. As a consequence, no association could be established between the serological condition and ELA-DRA. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. European Aedes albopictus and Culex pipiens Are Competent Vectors for Japanese Encephalitis Virus.

    Directory of Open Access Journals (Sweden)

    Mélissanne de Wispelaere

    2017-01-01

    Full Text Available Japanese encephalitis virus (JEV is the causative agent of Japanese encephalitis, the leading cause of viral encephalitis in Asia. JEV transmission cycle involves mosquitoes and vertebrate hosts. The detection of JEV RNA in a pool of Culex pipiens caught in 2010 in Italy raised the concern of a putative emergence of the virus in Europe. We aimed to study the vector competence of European mosquito populations, such as Cx. pipiens and Aedes albopictus for JEV genotypes 3 and 5.After oral feeding on an infectious blood meal, mosquitoes were dissected at various times post-virus exposure. We found that the peak for JEV infection and transmission was between 11 and 13 days post-virus exposure. We observed a faster dissemination of both JEV genotypes in Ae. albopictus mosquitoes, when compared with Cx. pipiens mosquitoes. We also dissected salivary glands and collected saliva from infected mosquitoes and showed that Ae. albopictus mosquitoes transmitted JEV earlier than Cx. pipiens. The virus collected from Ae. albopictus and Cx. pipiens saliva was competent at causing pathogenesis in a mouse model for JEV infection. Using this model, we found that mosquito saliva or salivary glands did not enhance the severity of the disease.In this study, we demonstrated that European populations of Ae. albopictus and Cx. pipiens were efficient vectors for JEV transmission. Susceptible vertebrate species that develop high viremia are an obligatory part of the JEV transmission cycle. This study highlights the need to investigate the susceptibility of potential JEV reservoir hosts in Europe, notably amongst swine populations and local water birds.

  8. European Aedes albopictus and Culex pipiens Are Competent Vectors for Japanese Encephalitis Virus.

    Science.gov (United States)

    de Wispelaere, Mélissanne; Desprès, Philippe; Choumet, Valérie

    2017-01-01

    Japanese encephalitis virus (JEV) is the causative agent of Japanese encephalitis, the leading cause of viral encephalitis in Asia. JEV transmission cycle involves mosquitoes and vertebrate hosts. The detection of JEV RNA in a pool of Culex pipiens caught in 2010 in Italy raised the concern of a putative emergence of the virus in Europe. We aimed to study the vector competence of European mosquito populations, such as Cx. pipiens and Aedes albopictus for JEV genotypes 3 and 5. After oral feeding on an infectious blood meal, mosquitoes were dissected at various times post-virus exposure. We found that the peak for JEV infection and transmission was between 11 and 13 days post-virus exposure. We observed a faster dissemination of both JEV genotypes in Ae. albopictus mosquitoes, when compared with Cx. pipiens mosquitoes. We also dissected salivary glands and collected saliva from infected mosquitoes and showed that Ae. albopictus mosquitoes transmitted JEV earlier than Cx. pipiens. The virus collected from Ae. albopictus and Cx. pipiens saliva was competent at causing pathogenesis in a mouse model for JEV infection. Using this model, we found that mosquito saliva or salivary glands did not enhance the severity of the disease. In this study, we demonstrated that European populations of Ae. albopictus and Cx. pipiens were efficient vectors for JEV transmission. Susceptible vertebrate species that develop high viremia are an obligatory part of the JEV transmission cycle. This study highlights the need to investigate the susceptibility of potential JEV reservoir hosts in Europe, notably amongst swine populations and local water birds.

  9. Low Protective Efficacy of the Current Japanese Encephalitis Vaccine against the Emerging Genotype 5 Japanese Encephalitis Virus.

    Science.gov (United States)

    Cao, Lei; Fu, Shihong; Gao, Xiaoyan; Li, Minghua; Cui, Shiheng; Li, Xiaolong; Cao, Yuxi; Lei, Wenwen; Lu, Zhi; He, Ying; Wang, Huanyu; Yan, Jinghua; Gao, George Fu; Liang, Guodong

    2016-05-01

    The current Japanese encephalitis (JE) vaccine derived from G3 JE virus (JEV) can induce protective immunity against G1-G4 JEV genotypes. However, protective efficacy against the emerging G5 genotype has not been reported. Using in vitro and in vivo tests, biological phenotype and cross-immunoreactions were compared between G3 JEV and G5 JEV (wild strains). The PRNT90 method was used to detect neutralizing antibodies against different genotypes of JEV in JE vaccine-immunized subjects and JE patients. In JE vaccine-immunized mice, the lethal challenge protection rates against G3 and G5 JEV wild strains were 100% and 50%, respectively. The seroconversion rates (SCRs) of virus antibodies against G3 and G5 JEV among vaccinated healthy subjects were 100% and 35%, respectively. All clinically identified JE patients showed high levels of G3 JEV neutralizing antibodies (≥1:10-1280) with positive serum geometric mean titers (GMTs) of 43.2, while for G5 JEV, neutralizing antibody conversion rates were only 64% with positive serum GMTs of 11.14. Moreover, the positive rate of JEV neutralizing antibodies against G5 JEV in pediatric patients was lower than in adults. Low levels of neutralizing/protective antibodies induced by the current JE vaccine, based on the G3 genotype, were observed against the emerging G5 JEV genotype. Our results demonstrate the need for more detailed studies to reevaluate whether or not the apparent emergence of G5 JEV can be attributed to failure of the current vaccine to induce appropriate immune protectivity against this genotype of JEV.

  10. Detection of West Nile virus and tick-borne encephalitis virus in birds in Slovakia, using a universal primer set.

    Science.gov (United States)

    Csank, Tomáš; Bhide, Katarína; Bencúrová, Elena; Dolinská, Saskia; Drzewnioková, Petra; Major, Peter; Korytár, Ľuboš; Bocková, Eva; Bhide, Mangesh; Pistl, Juraj

    2016-06-01

    West Nile virus (WNV) is a mosquito-borne neurotropic pathogen that presents a major public health concern. Information on WNV prevalence and circulation in Slovakia is insufficient. Oral and cloacal swabs and bird brain samples were tested for flavivirus RNA by RT-PCR using newly designed generic primers. The species designation was confirmed by sequencing. WNV was detected in swab and brain samples, whereas one brain sample was positive for tick-borne encephalitis virus (TBEV). The WNV sequences clustered with lineages 1 and 2. These results confirm the circulation of WNV in birds in Slovakia and emphasize the risk of infection of humans and horses.

  11. Antiviral Activity of Baicalein and Quercetin against the Japanese Encephalitis Virus

    Directory of Open Access Journals (Sweden)

    Jefree Johari

    2012-12-01

    Full Text Available Japanese encephalitis (JE, a mosquito-borne viral disease, is endemic to the entire east and southeast Asia, and some other parts of the world. Currently, there is no effective therapeutic available for JE; therefore, finding the effective antiviral agent against JEV replication is crucial. In the present study, the in vitro antiviral activity of baicalein and quercetin, two purportedly antiviral bioflavonoids, was evaluated against Japanese encephalitis virus (JEV replication in Vero cells. Anti-JEV activities of these compounds were examined on different stages of JEV replication cycle. The effects of the compounds on virus replication were determined by foci forming unit reduction assay (FFURA and quantitative RT-PCR. Baicalein showed potent antiviral activity with IC50 = 14.28 µg/mL when it was introduced to the Vero cells after adsorption of JEV. Quercetin exhibited weak anti-JEV effects with IC50 = 212.1 µg/mL when the JEV infected cells were treated with the compound after virus adsorption. However, baicalein exhibited significant effect against JEV adsorption with IC50 = 7.27 µg/mL while quercetin did not show any anti-adsorption activity. Baicalein also exhibited direct extracellular virucidal activity on JEV with IC50 = 3.44 µg/mL. However, results of quantitative RT-PCR experiments confirmed the findings from FFURA. This study demonstrated that baicalein should be considered as an appropriate candidate for further investigations, such as the study of molecular and cellular mechanism(s of action and in vivo evaluation for the development of an effective antiviral compound against Japanese encephalitis virus.

  12. CLEC5A regulates Japanese encephalitis virus-induced neuroinflammation and lethality.

    Directory of Open Access Journals (Sweden)

    Szu-Ting Chen

    Full Text Available CLEC5A/MDL-1, a member of the myeloid C-type lectin family expressed on macrophages and neutrophils, is critical for dengue virus (DV-induced hemorrhagic fever and shock syndrome in Stat1⁻/⁻ mice and ConA-treated wild type mice. However, whether CLEC5A is involved in the pathogenesis of viral encephalitis has not yet been investigated. To investigate the role of CLEC5A to regulate JEV-induced neuroinflammation, antagonistic anti-CLEC5A mAb and CLEC5A-deficient mice were generated. We find that Japanese encephalitis virus (JEV directly interacts with CLEC5A and induces DAP12 phosphorylation in macrophages. In addition, JEV activates macrophages to secrete proinflammatory cytokines and chemokines, which are dramatically reduced in JEV-infected Clec5a⁻/⁻ macrophages. Although blockade of CLEC5A cannot inhibit JEV infection of neurons and astrocytes, anti-CLEC5A mAb inhibits JEV-induced proinflammatory cytokine release from microglia and prevents bystander damage to neuronal cells. Moreover, JEV causes blood-brain barrier (BBB disintegrity and lethality in STAT1-deficient (Stat1⁻/⁻ mice, whereas peripheral administration of anti-CLEC5A mAb reduces infiltration of virus-harboring leukocytes into the central nervous system (CNS, restores BBB integrity, attenuates neuroinflammation, and protects mice from JEV-induced lethality. Moreover, all surviving mice develop protective humoral and cellular immunity against JEV infection. These observations demonstrate the critical role of CLEC5A in the pathogenesis of Japanese encephalitis, and identify CLEC5A as a target for the development of new treatments to reduce virus-induced brain damage.

  13. Cortical cholinergic decline parallels the progression of Borna virus encephalitis

    NARCIS (Netherlands)

    Gies, U; Gorcs, TJ; Mulder, J; Planz, O; Stitz, L; Bilzer, T; Luiten, PGM; Harkany, T; Görcs, Tamás J.

    2001-01-01

    Borna disease virus (BDV)-induced meningoencephalitis is associated with the dysfunction of the cholinergic system. Temporal development of this cholinergic decline during pre-encephalitic and encephalitic stages of BDV infection remains however elusive. Changes in choline acetyltransferase (ChAT)

  14. Infection and pathogenesis of canine, equine, and human influenza viruses in canine tracheas.

    Science.gov (United States)

    Gonzalez, Gaelle; Marshall, John F; Morrell, Joanna; Robb, David; McCauley, John W; Perez, Daniel R; Parrish, Colin R; Murcia, Pablo R

    2014-08-01

    Influenza A viruses (IAVs) can jump species barriers and occasionally cause epidemics, epizootics, pandemics, and panzootics. Characterizing the infection dynamics at the target tissues of natural hosts is central to understanding the mechanisms that control host range, tropism, and virulence. Canine influenza virus (CIV; H3N8) originated after the transfer of an equine influenza virus (EIV) into dogs. Thus, comparing CIV and EIV isolates provides an opportunity to study the determinants of influenza virus emergence. Here we characterize the replication of canine, equine, and human IAVs in the trachea of the dog, a species to which humans are heavily exposed. We define a phenotype of infection for CIV, which is characterized by high levels of virus replication and extensive tissue damage. CIV was compared to evolutionarily distinct EIVs, and the early EIV isolates showed an impaired ability to infect dog tracheas, while EIVs that circulated near the time of CIV emergence exhibited a CIV-like infection phenotype. Inoculating dog tracheas with various human IAVs (hIAVs) showed that they infected the tracheal epithelium with various efficiencies depending on the virus tested. Finally, we show that reassortant viruses carrying gene segments of CIV and hIAV are viable and that addition of the hemagglutinin (HA) and neuraminidase (NA) of CIV to the 2009 human pandemic virus results in a virus that replicates at high levels and causes significant lesions. This provides important insights into the role of evolution on viral emergence and on the role of HA and NA as determinants of pathogenicity. Influenza A viruses (IAVs) have entered new host species in recent history, sometimes with devastating consequences. Canine influenza virus (CIV) H3N8 originated from a direct transfer of an equine influenza virus (EIV) in the early 2000s. We studied the infection patterns of IAVs that circulate in dogs or to which dogs are commonly exposed and showed that CIV emergence was likely

  15. Changing Trend of T lymphocytes in Mouse Spleen after Japanese Encephalitis Virus Infection

    Directory of Open Access Journals (Sweden)

    Yan-fang Sun§, Chang-qin Gu§, Rong Jiang , Jing Ye, Yong-mao Li, Hua-zhen Liu , Hui Song and Ke-mei Peng*

    2011-10-01

    Full Text Available Japanese encephalitis is caused by Japanese encephalitis viruses (JEV with neurotropism. As one of the most important immune organ, spleen is directly involved in immune response against JEV. However, little research about JEV infection process in spleen has been reported. In this study, immunopathological changes in mouse spleen were analyzed every other day after subcutaneous injection of mice with JEV wild-type strain P3 by immunohistochemistry assay. Immunohistochemistry analysis demonstrated that the number of T lymphocytes was reduced from 0 to 3 DPI, increased from 3 to 7 DPI, and reduced again from 7 to 10 DPI. In addition, neurological dysfunction appeared at 6 DPI. These results suggested that spleen of mice suffered incontrovertible damages in influence of JEV infection. It can also be deduced that the cellular immunity took the crucial part in the first phase of transient viremia against JEV. Moreover, immune response was activated after the immune-depressed period in the first phase of viremia and neurological dysfunction appeared when cellular immunity was activated. Taking together, our research showed distinct immunopathological changes in mice after JEV infection, which enriched our understanding of Japanese encephalitis immunopathogenesis.

  16. Different pattern of haemagglutinin immunoreactivity of equine influenza virus strains isolated in Poland

    Directory of Open Access Journals (Sweden)

    Kwaśnik Małgorzata

    2015-12-01

    Full Text Available The immunoreactivity of haemagglutinin (HA polypeptides of equine influenza virus was compared among the strains isolated in Poland, using H3 monoclonal antibody. A stronger signal in immunoblot reaction was observed for A/equi/Pulawy/2008 HA polypeptides compared to A/equi/Pulawy/2006, despite the fact that both strains are phylogenetically closely related and belong to Florida clade 2 of American lineage. The strongest signal, observed in the case of A/equi/Pulawy/2008, seemed to be connected with the presence of G135, I213, E379, and/or V530 instead of R135, M213, G379, and I530 present in A/equi/Pulawy/2006 HA sequence. This implies that point mutations within amino acid sequences of HA polypeptides of equine influenza virus may change their immunoreactivity even when they are not located within five basic antigenic sites.

  17. Antiviral Activity of Isatis indigotica Extract and Its Derived Indirubin against Japanese Encephalitis Virus

    Directory of Open Access Journals (Sweden)

    Shu-Jen Chang

    2012-01-01

    Full Text Available Isatis indigotica is widely used in Chinese Traditional Medicine for clinical treatment of virus infection, tumor, and inflammation, yet its antiviral activities remain unclear. This study probed antiviral activity of I. indigotica extract and its marker compounds against Japanese encephalitis virus (JEV. I. indigotica methanol extract, indigo, and indirubin proved less cytotoxic than other components, showing inhibitory effect (concentration-dependent on JEV replication in vitro. Time-of-addition experiments proved the extract, indigo, and indirubin with potent antiviral effect by pretreatment (before infection or simultaneous treatment (during infection, but not posttreatment (after entry. Antiviral action of these agents showed correlation with blocking virus attachment and exhibited potent virucidal activity. In particular, indirubin had strong protective ability in a mouse model with lethal JEV challenge. The study could yield anti-JEV agents.

  18. STUDIES ON THE BIOCHEMICAL, BIOPHYSICAL, AND IMMUNOGENIC PROPERTIES OF JAPANESE B TYPE ENCEPHALITIS VIRUS AND VACCINES.

    Science.gov (United States)

    Duffy, C E; Stanley, W M

    1945-11-30

    Studies on the biochemical, biophysical, and immunogenic properties of Japanese B type encephalitis virus and vaccines have been made in order to determine whether a purified vaccine suitable for human use could be obtained by means of differential centrifugation of extracts of infected mouse brains. Studies were also made on extracts of normal mouse brains, it was found that extracts of normal as well as of infected mouse brains contained fairly large amounts of several components of high molecular weight. Components having sedimentation constants near 5 and 40 Svedberg units were found in extracts of infected brains. However the rates of sedimentation of the different components were so similar that it was found impossible, from a practical standpoint, to secure a vaccine consisting largely of virus by means of differential centrifugation. It was also found that a considerable portion of virus was lost or destroyed in the centrifugation process so that it was impossible to secure an effective degree of concentration of immunogenic potency. Although vaccines possessing about twice the immunogenic potency of the starting material were obtained, it was concluded that it was not practical to purify and concentrate Japanese B type encephalitis virus in infected mouse brain extracts by means of differential centrifugation for the production of a vaccine on a large scale. The optimum pH stability range of Japanese B type encephalitis virus activity was found to be near pH 8.5. The virus is inactivated fairly rapidly at pH 7 and very rapidly at more acid reactions. The virus is inactivated rapidly near pH 10. Extracts of infected mouse brains with buffers near pH 8 containing disodium phosphate were found to possess slightly higher titers than saline extracts near pH 7. However vaccines prepared from such extracts were found to possess essentially the same immunogenic potency, hence, although extraction at the more alkaline reaction may perhaps remove more active virus

  19. Safety and immunogenicity of a live attenuated Japanese encephalitis chimeric virus vaccine (IMOJEV®) in children.

    Science.gov (United States)

    Chokephaibulkit, K; Houillon, G; Feroldi, E; Bouckenooghe, A

    2016-01-01

    JE-CV (IMOJEV®, Sanofi Pasteur, France) is a live attenuated virus vaccine constructed by inserting coding sequences of the prM and E structural proteins of the Japanese encephalitis SA14-14-2 virus into the genome of yellow fever 17D virus. Primary immunization with JE-CV requires a single dose of the vaccine. This article reviews clinical trials of JE-CV in children aged up to 6 years conducted in countries across South-East Asia. Strong and persistent antibody responses were observed after single primary and booster doses, with 97% of children seroprotected up to five years after booster vaccination. Models of long-term antibody persistence predict a median duration of protection of approximately 30 years after a booster dose. The safety and reactogenicity profiles of JE-CV primary and booster doses are comparable to other widely used childhood vaccines.

  20. Intensive Circulation of Japanese Encephalitis Virus in Peri-urban Sentinel Pigs near Phnom Penh, Cambodia.

    Directory of Open Access Journals (Sweden)

    Julien Cappelle

    2016-12-01

    Full Text Available Despite the increased use of vaccination in several Asian countries, Japanese Encephalitis (JE remains the most important cause of viral encephalitis in Asia in humans with an estimated 68,000 cases annually. Considered a rural disease occurring mainly in paddy-field dominated landscapes where pigs are amplifying hosts, JE may nevertheless circulate in a wider range of environment given the diversity of its potential hosts and vectors. The main objective of this study was to assess the intensity of JE transmission to pigs in a peri-urban environment in the outskirt of Phnom Penh, Cambodia. We estimated the force of JE infection in two cohorts of 15 sentinel pigs by fitting a generalised linear model on seroprevalence monitoring data observed during two four-month periods in 2014. Our results provide evidence for intensive circulation of JE virus in a periurban area near Phnom Penh, the capital and most populated city of Cambodia. Understanding JE virus transmission in different environments is important for planning JE virus control in the long term and is also an interesting model to study the complexity of vector-borne diseases. Collecting quantitative data such as the force of infection will help calibrate epidemiological model that can be used to better understand complex vector-borne disease epidemiological cycles.

  1. Intensive Circulation of Japanese Encephalitis Virus in Peri-urban Sentinel Pigs near Phnom Penh, Cambodia.

    Science.gov (United States)

    Cappelle, Julien; Duong, Veasna; Pring, Long; Kong, Lida; Yakovleff, Maud; Prasetyo, Didot Budi; Peng, Borin; Choeung, Rithy; Duboz, Raphaël; Ong, Sivuth; Sorn, San; Dussart, Philippe; Tarantola, Arnaud; Buchy, Philippe; Chevalier, Véronique

    2016-12-01

    Despite the increased use of vaccination in several Asian countries, Japanese Encephalitis (JE) remains the most important cause of viral encephalitis in Asia in humans with an estimated 68,000 cases annually. Considered a rural disease occurring mainly in paddy-field dominated landscapes where pigs are amplifying hosts, JE may nevertheless circulate in a wider range of environment given the diversity of its potential hosts and vectors. The main objective of this study was to assess the intensity of JE transmission to pigs in a peri-urban environment in the outskirt of Phnom Penh, Cambodia. We estimated the force of JE infection in two cohorts of 15 sentinel pigs by fitting a generalised linear model on seroprevalence monitoring data observed during two four-month periods in 2014. Our results provide evidence for intensive circulation of JE virus in a periurban area near Phnom Penh, the capital and most populated city of Cambodia. Understanding JE virus transmission in different environments is important for planning JE virus control in the long term and is also an interesting model to study the complexity of vector-borne diseases. Collecting quantitative data such as the force of infection will help calibrate epidemiological model that can be used to better understand complex vector-borne disease epidemiological cycles.

  2. Seroprevalence of caprine artritis-encephalitis virus in goats of Lima region, Peru

    OpenAIRE

    Gomes M., Angel; Laboratorio de Microbiología y Parasitología Veterinaria, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima; Rivera G., Hermelinda; Laboratorio de Microbiología y Parasitología Veterinaria, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima Perú.; Ramírez V., Mercy; Laboratorio de Microbiología y Parasitología Veterinaria, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima; Cardozo Z., Imelda; Servicio Nacional de Sanidad Animal (SENASA), Lima; Manchego S., Alberto; Laboratorio de Microbiología y Parasitología Veterinaria, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima

    2015-01-01

    The seroprevalence of caprine artritis-encephalitis virus (CAEV) in four provinces of Lima Region, Peru was determined in 381 goat serum samples (325 females and 56 males) older than 12 months from 89 flocks reared under intensive (n=3), semiextensive (n=49) and transhumant (n=46) production systems. The detection of antibodies against CAEV was done by a competitive-inhibition ELISA test. The overall seroprevalence of CAEV was 0.26 ± 0.09% (1/381). The seropositive goat belonged to one flock ...

  3. BK virus encephalitis with thrombotic microangiopathy in an allogeneic hematopoietic stem cell transplant recipient.

    Science.gov (United States)

    Lopes da Silva, R; Ferreira, I; Teixeira, G; Cordeiro, D; Mafra, M; Costa, I; Bravo Marques, J M; Abecasis, M

    2011-04-01

    BK virus (BKV) infection occurs most often in immunocompromised hosts, in the setting of renal or bone marrow transplantation. Hemorrhagic cystitis is the commonest manifestation but in recent years infections in other organ systems have been reported. We report an unusual case of biopsy-proven BKV encephalitis in a hematopoietic stem cell transplant patient who subsequently developed thrombotic microangiopathy. As far as we know, this is the first report of such an association in a transplant patient. © 2010 John Wiley & Sons A/S.

  4. Siberian subtype tick-borne encephalitis virus in Ixodes ricinus in a newly emerged focus, Finland.

    Science.gov (United States)

    Jääskeläinen, Anu; Tonteri, Elina; Pieninkeroinen, Ilkka; Sironen, Tarja; Voutilainen, Liina; Kuusi, Markku; Vaheri, Antti; Vapalahti, Olli

    2016-02-01

    The first tick-borne encephalitis (TBE) cases in Kotka, Finland appeared in 2010. Altogether ten human cases have been diagnosed by 2014. Four had long-lasting sequelae. We collected 195 Ixodes ricinus ticks, nine rodents, and eleven shrews from the archipelago of Kotka in 2011. Three Siberian subtype TBE virus (TBEV) strains were isolated from the ticks and three mammals were positive for TBEV antibodies. The archipelago of Kotka is a newly emerged TBE focus of Siberian subtype TBEV circulating notably in I. ricinus. The patients had on average longer hospitalization than reported for the European subtype infection. Copyright © 2015 Elsevier GmbH. All rights reserved.

  5. Equine arteritis virus gP5 protein induces apoptosis in cultured insect cells

    OpenAIRE

    Metz, German Ernesto; Serena, Maria Soledad; Abeyá, María Mercedes; Dulbecco, Andrea Belén; Massone, Adriana; Diaz, Silvina; Echeverria, Maria Gabriela

    2017-01-01

    Equine Arteritis Virus (EAV) has been shown to induce apoptosis in vitro but the induction of this mechanism has not been previously associated with any viral gene product. In this work, we found a cytotoxicity effect of the EAV gP5 protein on baculovirus-insect cells and a low yield of protein recovery. Besides, different morphological features by electron transmission microscopy, DNA fragmentation in agarose gel, TUNEL analysis and caspase 3 activity were found. All these findings indicate ...

  6. Yellow fever/Japanese encephalitis chimeric viruses: construction and biological properties.

    Science.gov (United States)

    Chambers, T J; Nestorowicz, A; Mason, P W; Rice, C M

    1999-04-01

    A system has been developed for generating chimeric yellow fever/Japanese encephalitis (YF/JE) viruses from cDNA templates encoding the structural proteins prM and E of JE virus within the backbone of a molecular clone of the YF17D strain. Chimeric viruses incorporating the proteins of two JE strains, SA14-14-2 (human vaccine strain) and JE Nakayama (JE-N [virulent mouse brain-passaged strain]), were studied in cell culture and laboratory mice. The JE envelope protein (E) retained antigenic and biological properties when expressed with its prM protein together with the YF capsid; however, viable chimeric viruses incorporating the entire JE structural region (C-prM-E) could not be obtained. YF/JE(prM-E) chimeric viruses grew efficiently in cells of vertebrate or mosquito origin compared to the parental viruses. The YF/JE SA14-14-2 virus was unable to kill young adult mice by intracerebral challenge, even at doses of 10(6) PFU. In contrast, the YF/JE-N virus was neurovirulent, but the phenotype resembled parental YF virus rather than JE-N. Ten predicted amino acid differences distinguish the JE E proteins of the two chimeric viruses, therefore implicating one or more residues as virus-specific determinants of mouse neurovirulence in this chimeric system. This study indicates the feasibility of expressing protective antigens of JE virus in the context of a live, attenuated flavivirus vaccine strain (YF17D) and also establishes a genetic system for investigating the molecular basis for neurovirulence determinants encoded within the JE E protein.

  7. Characterisation of three equine influenza A H3N8 viruses from Germany (2000 and 2002): evidence for frozen evolution.

    Science.gov (United States)

    Borchers, Kerstin; Daly, Janet; Stiens, Gerhard; Kreling, Kai; Kreling, Inka; Ludwig, Hanns

    2005-04-25

    Reported here are the results of antigenic and genetic characterisation of equine influenza strains causing local outbreaks reported to the Equine Diagnostic Centre in Berlin, Germany. In 2000, equine influenza virus was detected in a nasal swab from a non-vaccinated horse using a rapid diagnostic kit, but was not successfully isolated. Partial direct sequencing of the haemagglutinin (HA1) gene, indicated that the virus was a European lineage H3N8 subtype strain representative of strains isolated in several European countries during 2000. In 2002, two equine influenza viruses were isolated from nasal swabs both taken from unvaccinated horses with acute respiratory symptoms housed at the same stables. Antigenic characterisation using a panel of ferret antisera suggested that these isolates also belonged to the European lineage of H3N8 viruses. Analysis of deduced HA1 amino acid sequences confirmed that the HA1 of both isolates were identical and belonged to the European lineage. However, from phylogenetic analysis, both strains appeared to be more closely related to viruses isolated between 1989 and 1995 than to viruses isolated more recently in Europe. These results suggested that viruses with fewer changes than those on the main evolutionary lineage may continue to circulate. The importance of expanding current equine influenza surveillance efforts is emphasised.

  8. Neutralizing activities of human immunoglobulin derived from donors in Japan against mosquito-borne flaviviruses, Japanese encephalitis virus, West Nile virus, and dengue virus

    Directory of Open Access Journals (Sweden)

    Yunoki M

    2016-07-01

    Full Text Available Mikihiro Yunoki,1-3 Takeshi Kurosu,2 Ritsuko Kubota Koketsu,2,4 Kazuo Takahashi,5 Yoshinobu Okuno,4 Kazuyoshi Ikuta2,4 1Research and Development Division, Japan Blood Products Organization, Tokyo, 2Department of Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, 3Pathogenic Risk Evaluation, Graduate School of Veterinary Medicine, Rakuno Gakuen University, Hokkaido, 4Research and Development Division, The Research Foundation for Microbial Diseases of Osaka University, Kagawa, 5Osaka Prefectural Institute of Public Health, Osaka, Japan Abstract: Japanese encephalitis virus (JEV, West Nile virus (WNV, and dengue virus (DenV are causal agents of Japanese encephalitis, West Nile fever, and dengue fever, respectively. JEV is considered to be indigenized and widespread in Japan, whereas WNV and DenV are not indigenized in Japan. Globulin products seem to reflect the status of the donor population according to antivirus neutralization activity. However, the anti-JEV, -WNV, and -DenV neutralization activities of globulin products derived from donors in Japan have not been clarified. Furthermore, potential candidates for the development of an effective immunotherapeutic drug for encephalitis caused by JEV, WNV, or DenV have also not been identified. Therefore, the aim of this study was to determine the overall status of the donor population in Japan based on globulin products by evaluating anti-JEV, -WNV, and -DenV neutralizing activities of intravenous immunoglobulin. Overall, intravenous immunoglobulin products showed stable neutralizing activity against JEV but showed no or only weak activity against WNV or DenV. These results suggest that the epidemiological level against WNV and DenV in the donor population of Japan is still low, suggesting that these viruses are not yet indigenized. In addition, JEV vaccinations and/or infections in the donor population do not induce a cross-reactive antibody against WNV. Keywords

  9. The effects of equine rhinovirus, influenza virus and herpesvirus infection on tracheal clearance rate in horses.

    Science.gov (United States)

    Willoughby, R; Ecker, G; McKee, S; Riddolls, L; Vernaillen, C; Dubovi, E; Lein, D; Mahony, J B; Chernesky, M; Nagy, E

    1992-04-01

    The response of horses exposed to three common respiratory viruses was studied by measuring tracheal mucociliary clearance rates in the trachea. Tracheal clearance rates (TCR) were determined before, during illness and following recovery in horses exposed to equine rhinovirus (ERhV-2), equine influenza virus (EIV) and equine herpesvirus (EHV-4) by means of lateral scintigraphs made following an injection of technetium-99m sulphide colloid into the tracheal lumen. In six horses exposed to ERhV-2, TCR remained within normal limits. Exposure to EIV resulted in reduced TCR in six of seven horses, with TCR remaining below the 95% confidence limits of normal values for each horse for up to 32 days despite the resolution of clinical signs. Moderate changes were observed in six horses exposed to EHV-4, but significant reductions in TCR were evident in three animals. Measurement of TCR was a useful, minimally-invasive technique which demonstrated that respiratory viruses may cause persistent changes in TCR, even though clinical signs are not evident.

  10. Encephalitis due to emerging viruses: CNS innate immunity and potential therapeutic targets.

    Science.gov (United States)

    Denizot, M; Neal, J W; Gasque, P

    2012-07-01

    The emerging viruses represent a group of pathogens that are intimately connected to a diverse range of animal vectors. The recent escalation of air travel climate change and urbanization has meant humans will have increased risk of contacting these pathogens resulting in serious CNS infections. Many RNA viruses enter the CNS by evading the BBB due to axonal transport from the periphery. The systemic adaptive and CNS innate immune systems express pattern recognition receptors PRR (TLRs, RiG-1 and MDA-5) that detect viral nucleic acids and initiate host antiviral response. However, several emerging viruses (West Nile Fever, Influenza A, Enterovirus 71 Ebola) are recognized and internalized by host cell receptors (TLR, MMR, DC-SIGN, CD162 and Scavenger receptor B) and escape immuno surveillance by the host systemic and innate immune systems. Many RNA viruses express viral proteins WNF (E protein), Influenza A (NS1), EV71 (protein 3C), Rabies (Glycoprotein), Ebola proteins (VP24 and VP 35) that inhibit the host cell anti-virus Interferon type I response promoting virus replication and encephalitis. The therapeutic use of RNA interference methodologies to silence gene expression of viral peptides and treat emerging virus infection of the CNS is discussed. Copyright © 2012. Published by Elsevier Ltd.

  11. Antibodies to H5 subtype avian influenza virus and Japanese encephalitis virus in northern pintails (Anas acuta) sampled in Japan

    Science.gov (United States)

    Ramey, Andy M.; Spackman, Erica; Yeh, Jung-Yong; Fujita, Go; Konishi, Kan; Reed, John A.; Wilcox, Benjamin R.; Brown, Justin D.; Stallknecht, David E.

    2013-01-01

    Blood samples from 105 northern pintails (Anas acuta) captured on Hokkaido, Japan were tested for antibodies to avian influenza virus (AIV), Japanese encephalitis virus (JEV), and West Nile virus (WNV) to assess possible involvement of this species in the spread of economically important and potentially zoonotic pathogens. Antibodies to AIV were detected in 64 of 105 samples (61%). Of the 64 positives, 95% and 81% inhibited agglutination of two different H5 AIV antigens (H5N1 and H5N9), respectively. Antibodies to JEV and WNV were detected in five (5%) and none of the samples, respectively. Results provide evidence for prior exposure of migrating northern pintails to H5 AIV which couldhave implications for viral shedding and disease occurrence. Results also provide evidence for limited involvement of this species in the transmission and spread of flaviviruses during spring migration.

  12. Review of climate, landscape, and viral genetics as drivers of the Japanese encephalitis virus ecology.

    Directory of Open Access Journals (Sweden)

    Guillaume Le Flohic

    Full Text Available The Japanese encephalitis virus (JEV, an arthropod-born Flavivirus, is the major cause of viral encephalitis, responsible for 10,000-15,000 deaths each year, yet is a neglected tropical disease. Since the JEV distribution area has been large and continuously extending toward new Asian and Australasian regions, it is considered an emerging and reemerging pathogen. Despite large effective immunization campaigns, Japanese encephalitis remains a disease of global health concern. JEV zoonotic transmission cycles may be either wild or domestic: the first involves wading birds as wild amplifying hosts; the second involves pigs as the main domestic amplifying hosts. Culex mosquito species, especially Cx. tritaeniorhynchus, are the main competent vectors. Although five JEV genotypes circulate, neither clear-cut genotype-phenotype relationship nor clear variations in genotype fitness to hosts or vectors have been identified. Instead, the molecular epidemiology appears highly dependent on vectors, hosts' biology, and on a set of environmental factors. At global scale, climate, land cover, and land use, otherwise strongly dependent on human activities, affect the abundance of JEV vectors, and of wild and domestic hosts. Chiefly, the increase of rice-cultivated surface, intensively used by wading birds, and of pig production in Asia has provided a high availability of resources to mosquito vectors, enhancing the JEV maintenance, amplification, and transmission. At fine scale, the characteristics (density, size, spatial arrangement of three landscape elements (paddy fields, pig farms, human habitations facilitate or impede movement of vectors, then determine how the JEV interacts with hosts and vectors and ultimately the infection risk to humans. If the JEV is introduced in a favorable landscape, either by live infected animals or by vectors, then the virus can emerge and become a major threat for human health. Multidisciplinary research is essential to shed

  13. Thiosemicarbazones and Phthalyl-Thiazoles compounds exert antiviral activity against yellow fever virus and Saint Louis encephalitis virus.

    Science.gov (United States)

    Pacca, Carolina Colombelli; Marques, Rafael Elias; Espindola, José Wanderlan P; Filho, Gevânio B O Oliveira; Leite, Ana Cristina Lima; Teixeira, Mauro Martins; Nogueira, Mauricio L

    2017-03-01

    Arboviruses, arthropod-borneviruses, are frequency associated to human outbreak and represent a serious health problem. The genus Flavivirus, such as Yellow Fever Virus (YFV) and Saint Louis Encephalitis Virus (SLEV), are important pathogens with high morbidity and mortality worldwide. In Brazil, YFV is maintained in sylvatic cycle, but many cases are notified annually, despite the efficiency of vaccine. SLEV causes an acute encephalitis and is widely distributed in the Americas. There is no specific antiviral drugs for these viruses, only supporting treatment that can alleviate symptoms and prevent complications. Here, we evaluated the potential anti-YFV and SLEV activity of a series of thiosemicarbazones and phthalyl-thiazoles. Plaque reduction assay, flow cytometry, immunofluorescence and cellular viability were used to test the compounds in vitro. Treated cells showed efficient inhibition of the viral replication at concentrations that presented minimal toxicity to cells. The assays showed that phthalyl-thiazole and phenoxymethyl-thiosemicarbazone reduced 60% of YFV replication and 75% of SLEV replication. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  14. Japanese encephalitis virus disrupts blood-brain barrier and modulates apoptosis proteins in THBMEC cells.

    Science.gov (United States)

    Al-Obaidi, Mazen M Jamil; Bahadoran, Azadeh; Har, Lee Sau; Mui, Wang Seok; Rajarajeswaran, Jayakumar; Zandi, Keivan; Manikam, Rishya; Sekaran, Shamala Devi

    2017-04-02

    Japanese encephalitis (JE) is a neurotropic flavivirus that causes inflammation in central nervous system (CNS), neuronal death and also compromises the structural and functional integrity of the blood-brain barrier (BBB). The aim of this study was to evaluate the BBB disruption and apoptotic process in Japanese encephalitis virus (JEV)-infected transfected human brain microvascular endothelial cells (THBMECs). THBMECs were overlaid by JEV with different MOIs (0.5, 1.0, 5.0 and 10.0) and monitored by electrical cell-substrate impedance sensing (ECIS) in a real-time manner in order to observe the barrier function of THBMECs. Additionally, the level of 43 apoptotic proteins was quantified in the virally infected cells with different MOIs at 24h post infection. Infection of THBMEC with JEV induced an acute reduction in transendothelial electrical resistance (TEER) after viral infection. Also, significant up-regulation of Bax, BID, Fas and Fasl and down-regulation of IGFBP-2, BID, p27 and p53 were observed in JEV infected THBMECs with 0.5 and 10 MOIs compared to uninfected cells. Hence, the permeability of THBMECs is compromised during the JEV infection. In addition high viral load of the virus has the potential to subvert the host cell apoptosis to optimize the course of viral infection through deactivation of pro-apoptotic proteins. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Molecular epidemiology of Japanese encephalitis virus in mosquitoes in Taiwan during 2005-2012.

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    Chien-Ling Su

    2014-10-01

    Full Text Available Japanese encephalitis (JE is a mosquito-borne zoonotic disease caused by the Japanese encephalitis virus (JEV. Pigs and water birds are the main amplifying and maintenance hosts of the virus. In this study, we conducted a JEV survey in mosquitoes captured in pig farms and water bird wetland habitats in Taiwan during 2005 to 2012. A total of 102,633 mosquitoes were collected. Culex tritaeniorhynchus was the most common mosquito species found in the pig farms and wetlands. Among the 26 mosquito species collected, 11 tested positive for JEV by RT-PCR, including Cx. tritaeniorhynchus, Cx. annulus, Anopheles sinensis, Armigeres subalbatus, and Cx. fuscocephala. Among those testing positive, Cx. tritaeniorhynchus was the predominant vector species for the transmission of JEV genotypes I and III in Taiwan. The JEV infection rate was significantly higher in the mosquitoes from the pig farms than those from the wetlands. A phylogenetic analysis of the JEV envelope gene sequences isolated from the captured mosquitoes demonstrated that the predominant JEV genotype has shifted from genotype III to genotype I (GI, providing evidence for transmission cycle maintenance and multiple introductions of the GI strains in Taiwan during 2008 to 2012. This study demonstrates the intense JEV transmission activity in Taiwan, highlights the importance of JE vaccination for controlling the epidemic, and provides valuable information for the assessment of the vaccine's efficacy.

  16. Cellular DDX3 regulates Japanese encephalitis virus replication by interacting with viral un-translated regions.

    Science.gov (United States)

    Li, Chen; Ge, Ling-ling; Li, Peng-peng; Wang, Yue; Dai, Juan-juan; Sun, Ming-xia; Huang, Li; Shen, Zhi-qiang; Hu, Xiao-chun; Ishag, Hassan; Mao, Xiang

    2014-01-20

    Japanese encephalitis virus is one of the most common causes for epidemic viral encephalitis in humans and animals. Herein we demonstrated that cellular helicase DDX3 is involved in JEV replication. DDX3 knockdown inhibits JEV replication. The helicase activity of DDX3 is crucial for JEV replication. GST-pulldown and co-immunoprecipitation experiments demonstrated that DDX3 could interact with JEV non-structural proteins 3 and 5. Co-immunoprecipitation and confocal microscopy analysis confirmed that DDX3 interacts and colocalizes with these viral proteins and viral RNA during the infection. We determined that DDX3 binds to JEV 5' and 3' un-translated regions. We used a JEV-replicon system to demonstrate that DDX3 positively regulates viral RNA translation, which might affect viral RNA replication at the late stage of virus infection. Collectively, we identified that DDX3 is necessary for JEV infection, suggesting that DDX3 might be a novel target to design new antiviral agents against JEV or other flavivirus infections. © 2013 Published by Elsevier Inc.

  17. Molecular Epidemiology of Japanese Encephalitis Virus in Mosquitoes in Taiwan during 2005–2012

    Science.gov (United States)

    Su, Chien-Ling; Yang, Cheng-Fen; Teng, Hwa-Jen; Lu, Liang-Chen; Lin, Cheo; Tsai, Kun-Hsien; Chen, Yu-Yu; Chen, Li-Yu; Chang, Shu-Fen; Shu, Pei-Yun

    2014-01-01

    Japanese encephalitis (JE) is a mosquito-borne zoonotic disease caused by the Japanese encephalitis virus (JEV). Pigs and water birds are the main amplifying and maintenance hosts of the virus. In this study, we conducted a JEV survey in mosquitoes captured in pig farms and water bird wetland habitats in Taiwan during 2005 to 2012. A total of 102,633 mosquitoes were collected. Culex tritaeniorhynchus was the most common mosquito species found in the pig farms and wetlands. Among the 26 mosquito species collected, 11 tested positive for JEV by RT-PCR, including Cx. tritaeniorhynchus, Cx. annulus, Anopheles sinensis, Armigeres subalbatus, and Cx. fuscocephala. Among those testing positive, Cx. tritaeniorhynchus was the predominant vector species for the transmission of JEV genotypes I and III in Taiwan. The JEV infection rate was significantly higher in the mosquitoes from the pig farms than those from the wetlands. A phylogenetic analysis of the JEV envelope gene sequences isolated from the captured mosquitoes demonstrated that the predominant JEV genotype has shifted from genotype III to genotype I (GI), providing evidence for transmission cycle maintenance and multiple introductions of the GI strains in Taiwan during 2008 to 2012. This study demonstrates the intense JEV transmission activity in Taiwan, highlights the importance of JE vaccination for controlling the epidemic, and provides valuable information for the assessment of the vaccine's efficacy. PMID:25275652

  18. The ecology of western equine encephalomyelitis virus in the Central Valley of California, 1945-1985.

    Science.gov (United States)

    Hardy, J L

    1987-11-01

    Reeves' concept of the summer transmission cycle of western equine encephalomyelitis virus in 1945 was that the virus was amplified in a silent transmission cycle involving mosquitoes, domestic chickens, and possibly wild birds, from which it could be transmitted tangentially to and cause disease in human and equine populations. Extensive field and laboratory studies done since 1945 in the Central Valley of California have more clearly defined the specific invertebrate and vertebrate hosts involved in the basic virus transmission cycle, but the overall concept remains unchanged. The basic transmission cycle involves Culex tarsalis as the primary vector mosquito species and house finches and house sparrows as the primary amplifying hosts. Secondary amplifying hosts, upon which Cx. tarsalis frequently feeds, include other passerine species, chickens, and possibly pheasants in areas where they are abundant. Another transmission cycle that most likely is initiated from the Cx. tarsalis-wild bird cycle involves Aedes melanimon and the blacktail jackrabbit. Like humans and horses, California ground squirrels, western tree squirrels, and a few other wild mammal species become infected tangentially with the virus but do not contribute significantly to virus amplification.

  19. Flaviviruses, an expanding threat in public health: focus on Dengue, West Nile, and Japanese encephalitis virus

    Science.gov (United States)

    Daep, Carlo Amorin; Muñoz-Jordán, Jorge L.; Eugenin, Eliseo Alberto

    2014-01-01

    The flaviviruses Dengue, West Nile, and Japanese encephalitis represent three major mosquito-borne viruses worldwide. These pathogens impact the lives of millions of individuals and potentially could affect non-endemic areas already colonized by mosquito vectors. Unintentional transport of infected vectors (Aedes and Culex sp), traveling within endemic areas, rapid adaptation of the insects into new geographic locations, climate change, and lack of medical surveillance have greatly contributed to the increase in flaviviral infections worldwide. The mechanisms by which flaviviruses alter the immune and the central nervous system have only recently been examined despite the alarming number of infections, related deaths, and increasing global distribution. In this review, we will discuss the expansion of the geographic areas affected by flaviviruses, the potential threats to previously unaffected countries, the mechanisms of pathogenesis, and the potential therapeutic interventions to limit the devastating consequences of these viruses. PMID:25287260

  20. Flaviviruses, an expanding threat in public health: focus on dengue, West Nile, and Japanese encephalitis virus.

    Science.gov (United States)

    Daep, Carlo Amorin; Muñoz-Jordán, Jorge L; Eugenin, Eliseo Alberto

    2014-12-01

    The flaviviruses dengue, West Nile, and Japanese encephalitis represent three major mosquito-borne viruses worldwide. These pathogens impact the lives of millions of individuals and potentially could affect non-endemic areas already colonized by mosquito vectors. Unintentional transport of infected vectors (Aedes and Culex spp.), traveling within endemic areas, rapid adaptation of the insects into new geographic locations, climate change, and lack of medical surveillance have greatly contributed to the increase in flaviviral infections worldwide. The mechanisms by which flaviviruses alter the immune and the central nervous system have only recently been examined despite the alarming number of infections, related deaths, and increasing global distribution. In this review, we will discuss the expansion of the geographic areas affected by flaviviruses, the potential threats to previously unaffected countries, the mechanisms of pathogenesis, and the potential therapeutic interventions to limit the devastating consequences of these viruses.

  1. Caveolin-1-mediated Japanese encephalitis virus entry requires a two-step regulation of actin reorganization.

    Science.gov (United States)

    Xu, Qingqiang; Cao, Mingmei; Song, Hongyuan; Chen, Shenglin; Qian, Xijing; Zhao, Ping; Ren, Hao; Tang, Hailin; Wang, Yan; Wei, Youheng; Zhu, Yongzhe; Qi, Zhongtian

    2016-10-01

    To investigate the detailed mechanism of Japanese encephalitis virus (JEV) cell entry. Utilize a siRNA library targeting cellular membrane trafficking genes to identify key molecules that mediate JEV entry into human neuronal cells. JEV enters human neuronal cells by caveolin-1-mediated endocytosis, which depends on a two-step regulation of actin cytoskeleton remodeling triggered by RhoA and Rac1: RhoA activation promoted the phosphorylation of caveolin-1, and then Rac1 activation facilitated caveolin-associated viral internalization. Specifically, virus attachment activates the EGFR-PI3K signaling pathway, thereby leading to RhoA activation. This work provides a detailed picture of the entry route and intricate cellular events following the entry of JEV into human neuronal cells, and promotes a better understanding of JEV entry.

  2. Delayed Diagnosis of Tuberculous Meningitis Misdiagnosed as Herpes Simplex Virus-1 Encephalitis With the FilmArray Syndromic Polymerase Chain Reaction Panel

    OpenAIRE

    Gomez, Carlos A.; Pinsky, Benjamin A.; Liu, Anne; Banaei, Niaz

    2016-01-01

    Abstract The FilmArray meningitis/encephalitis (ME) panel is a novel syndromic, nucleic acid amplification test for diagnosis of acute meningitis and encephalitis. Emerging data on its performance are concerning for false-positive results. We present a case of tuberculous meningitis misdiagnosed as herpes simplex virus-1 encephalitis with the FilmArray ME panel. Strategies to mitigate erroneous results are discussed.

  3. Isolation and Characterization of Equine Influenza Viruses (H3N8 from China, 2010~2011

    Directory of Open Access Journals (Sweden)

    Gang Lu1,§, Jie Chen2,§, Wei Guo1,§, Ting Qi1,§, Liping Zhao1, Hongmei Li1, Yuanyuan Ji1, Zheng Wang1, Cuiyun Liu1, Shihua Zhao1 and Wenhua Xiang1,*

    2013-04-01

    Full Text Available Two equine influenza virus (EIV strains were isolated during two restricted outbreaks from Heilongjiang Province, China in 2010 and 2011. Phylogenetic analysis of HA1 (hemagglutinin 1 gene revealed that the isolates belonged to Florida 2 sublineage of American lineage. Further analysis of the putative antigenic sites located in HA1 subunit protein revealed each isolate had a unique amino acid change. Analysis of antigenic sites between Chinese EIV and vaccine strains indicated equine influenza (EI vaccines containing Richmond/1/07-like antigen seemed to have an optimum effect in China. Meanwhile, the Ohio/03 vaccine strain contained in updated ProteqFlu had the most closely genetically relationship with recent EIV isolates in China. China has not its own commercially available EI vaccine and most horses are still unvaccinated. Therefore, to monitor antigenic variation of circulating EIVs and give considerable suggestions on selection of vaccine candidate plays an important role in preventing and controlling EIV in China.

  4. Phylogenetically distinct equine influenza viruses show different tropism for the swine respiratory tract.

    Science.gov (United States)

    Patrono, Livia V; Bonfante, Francesco; Zanardello, Claudia; Terregino, Calogero; Capua, Ilaria; Murcia, Pablo R

    2015-05-01

    Influenza A viruses circulate in a wide range of animals. H3N8 equine influenza virus (EIV) is an avian-origin virus that has established in dogs as canine influenza virus (CIV) and has also been isolated from camels and pigs. Previous work suggests that mutations acquired during EIV evolution might have played a role in CIV emergence. Given the potential role of pigs as a source of human infections, we determined the ability of H3N8 EIVs to replicate in pig cell lines and in respiratory explants. We show that phylogenetically distinct EIVs display different infection phenotypes along the pig respiratory tract, but not in cell lines. Our results suggest that EIV displays a dynamic host range along its evolutionary history, supporting the view that evolutionary processes play important roles in host range and tropism and also underscoring the utility of using explant cultures to study influenza pathogenesis. © 2015 The Authors.

  5. Isolation and full-genome sequences of Japanese encephalitis virus genotype I strains from Cambodian human patients, mosquitoes and pigs.

    Science.gov (United States)

    Duong, Veasna; Choeung, Rithy; Gorman, Christopher; Laurent, Denis; Crabol, Yoann; Mey, Channa; Peng, Borin; Di Francesco, Juliette; Hul, Vibol; Sothy, Heng; Santy, Ky; Richner, Beat; Pommier, Jean-David; Sorn, San; Chevalier, Véronique; Buchy, Philippe; de Lamballerie, Xavier; Cappelle, Julien; Horwood, Paul Francis; Dussart, Philippe

    2017-09-01

    Japanese encephalitis remains the most important cause of viral encephalitis in humans in several southeast Asian countries, including Cambodia, causing at least 65 000 cases of encephalitis per year. This vector-borne viral zoonosis - caused by Japanese encephalitis virus (JEV) - is considered to be a rural disease and is transmitted by mosquitoes, with birds and pigs being the natural reservoirs, while humans are accidental hosts. In this study we report the first two JEV isolations in Cambodia from human encephalitis cases from two studies on the aetiology of central nervous system disease, conducted at the two major paediatric hospitals in the country. We also report JEV isolation from Culextritaeniorhynchus mosquitoes and from pig samples collected in two farms, located in peri-urban and rural areas. Out of 11 reverse-transcription polymerase chain reaction-positive original samples, we generated full-genome sequences from 5 JEV isolates. Five additional partial sequences of the JEV NS3 gene from viruses detected in five pigs and one complete coding sequence of the envelope gene of a strain identified in a pig were generated. Phylogenetic analyses revealed that JEV detected in Cambodia belonged to genotype I and clustered in two clades: genotype I-a, mainly comprising strains from Thailand, and genotype I-b, comprising strains from Vietnam that dispersed northwards to China. Finally, in this study, we provide proof that the sequenced JEV strains circulate between pigs, Culex tritaeniorhynchus and humans in the Phnom Penh vicinity.

  6. Partially neutralizing potency against emerging genotype I virus among children received formalin-inactivated Japanese encephalitis virus vaccine.

    Directory of Open Access Journals (Sweden)

    Yi-Chin Fan

    Full Text Available BACKGROUND: Genotype I (GI Japanese encephalitis virus (JEV that replaced GIII virus has become the dominant circulating virus in Asia. Currently, all registered live and inactivated JEV vaccines are derived from genotype III viruses. In Taiwan, the compulsory JEV vaccination policy recommends that children receives four doses of formalin-inactivated Nakayama (GIII JEV vaccine. METHODOLOGY/PRINCIPAL FINDINGS: To evaluate the influence of genotype replacement on the post-vaccination viral neutralizing ability by GIII and GI viruses, the small panel of vaccinated-children serum specimens was assembled, and the reciprocal 50% plaque-reduction neutralizing antibody titers (PRNT(50 were measured against Nakayama vaccine strain, CJN GIII human brain isolate and TC2009-1 GI mosquito isolate. The seropositivity rate (PRNT(50 ≥ 1:10 and geometric mean titers (GMT against the TC2009-1 virus were the lowest among the three viruses. The protective threshold against the CJN and TC2009-1 viruses could only be achieved when the GMT against Nakayama virus was ≥ 1:20 or ≥ 1:80, respectively. Using undiluted vaccinees' sera, the enhancement of JEV infection in K562 cells was observed in some low or non-neutralizing serum specimens. CONCLUSIONS/SIGNIFICANCE: Our preliminary study has shown that neutralizing antibodies, elicited by the mouse brain-derived and formalin-inactivated JEV Nakayama vaccine among a limited number of vaccinees, have reduced neutralizing capacity against circulating GI virus, but more detailed studies are needed to address the potential impact on the future vaccine policy.

  7. A highly pathogenic porcine reproductive and respiratory syndrome virus candidate vaccine based on Japanese encephalitis virus replicon system.

    Science.gov (United States)

    Hu, Pingsheng; Chen, Xiaoming; Huang, Lihong; Liu, Shukai; Zang, Fuyu; Xing, Jinchao; Zhang, Youyue; Liang, Jiaqi; Zhang, Guihong; Liao, Ming; Qi, Wenbao

    2017-01-01

    In the swine industry, porcine reproductive and respiratory syndrome (PRRS) is a highly contagious disease which causes heavy economic losses worldwide. Effective prevention and disease control is an important issue. In this study, we described the construction of a Japanese encephalitis virus (JEV) DNA-based replicon with a cytomegalovirus (CMV) promoter based on the genome of Japanese encephalitis live vaccine virus SA14-14-2, which is capable of offering a potentially novel way to develop and produce vaccines against a major pathogen of global health. This JEV DNA-based replicon contains a large deletion in the structural genes (C-prM-E). A PRRSV GP5/M was inserted into the deletion position of JEV DNA-based replicons to develop a chimeric replicon vaccine candidate for PRRSV. The results showed that BALB/c mice models with the replicon vaccines pJEV-REP-G-2A-M-IRES and pJEV-REP-G-2A-M stimulated antibody responses and induced a cellular immune response. Analysis of ELSA data showed that vaccination with the replicon vaccine expressing GP5/M induced a better antibodies response than traditional DNA vaccines. Therefore, the results suggested that this ectopic expression system based on JEV DNA-based replicons may represent a useful molecular platform for various biological applications, and the JEV DNA-based replicons expressing GP5/M can be further developed into a novel, safe vaccine candidate for PRRS.

  8. Molecular characterization of equine infectious anaemia virus from a major outbreak in southeastern France.

    Science.gov (United States)

    Gaudaire, D; Lecouturier, F; Ponçon, N; Morilland, E; Laugier, C; Zientara, S; Hans, A

    2018-02-01

    In 2009, a major outbreak of equine infectious anaemia (EIA) was reported in the south-east of France. This outbreak affected three premises located in the Var region where the index case, a 10-year-old mare that exhibited clinical signs consistent with EIA, occurred at a riding school. Overall, more than 250 horses were tested for EIAV (equine infectious anaemia virus) antibodies, using agar gel immunodiffusion test, and 16 horses were positive in three different holdings. Epidemiological survey confirmed that the three premises were related through the purchase/sale of horses and the use of shared or nearby pastures. Molecular characterization of viruses was performed by sequencing the full gag gene sequence (1,400 bp) of the proviral DNAs retrieved from the spleen of infected animals collected post-mortem. Phylogenetic analysis confirmed epidemiological data from the field, as viruses isolated from the three premises were clustering together suggesting a common origin whereas some premises were 50 km apart. Moreover, viruses characterized during this outbreak are different from European strains described so far, underlying the high genetic diversity of EIAV in Europe. © 2017 Blackwell Verlag GmbH.

  9. Mesenchymal stem cells alleviate Japanese encephalitis virus-induced neuroinflammation and mortality.

    Science.gov (United States)

    Bian, Peiyu; Ye, Chuantao; Zheng, Xuyang; Yang, Jing; Ye, Wei; Wang, Yuan; Zhou, Yun; Ma, Hongwei; Han, Peijun; Zhang, Hai; Zhang, Ying; Zhang, Fanglin; Lei, Yingfeng; Jia, Zhansheng

    2017-02-16

    Japanese encephalitis virus (JEV) is the leading cause of viral encephalitis in Asia. Japanese encephalitis (JE) caused by JEV is characterized by extensive inflammatory cytokine secretion, microglia activation, blood-brain barrier (BBB) breakdown, and neuronal death, all of which contribute to the vicious cycle of inflammatory damage. There are currently no effective treatments for JE. Mesenchymal stem cells (MSCs) have been demonstrated to have a therapeutic effect on many central nervous system (CNS) diseases by regulating inflammation and other mechanisms. In vivo, 8- to 10-week-old mice were infected intraperitoneally with JEV and syngeneic bone marrow MSCs were administered through the caudal vein at 1 and 3 days post-infection. The mortality, body weight, and behavior were monitored daily. Brains from each group were harvested at the indicated times for hematoxylin and eosin staining, immunohistochemical observation, flow cytometric analysis, TUNEL staining, Western blot, quantitative real-time polymerase chain reaction, and BBB permeability assays. In vitro, co-culture and mixed culture experiments of MSCs with either microglia or neurons were performed, and then the activation state of microglia and survival rate of neurons were tested 48 h post-infection. MSC treatment reduced JEV-induced mortality and improved the recovery from JE in our mouse model. The inflammatory response, microglia activation, neuronal damage, BBB destruction, and viral load (VL) were significantly decreased in the MSC-treated group. In co-culture experiments, MSCs reprogrammed M1-to-M2 switching in microglia and improved neuron survival. Additionally, the VL was decreased in Neuro2a cells in the presence of MSCs accompanied by increased expression of interferon-α/β. MSC treatment alleviated JEV-induced inflammation and mortality in mice.

  10. Ecological Niche Modeling to Estimate the Distribution of Japanese Encephalitis Virus in Asia

    Science.gov (United States)

    Miller, Robin H.; Masuoka, Penny; Klein, Terry A.; Kim, Heung-Chul; Somer, Todd; Grieco, John

    2012-01-01

    Background Culex tritaeniorhynchus is the primary vector of Japanese encephalitis virus (JEV), a leading cause of encephalitis in Asia. JEV is transmitted in an enzootic cycle involving large wading birds as the reservoirs and swine as amplifying hosts. The development of a JEV vaccine reduced the number of JE cases in regions with comprehensive childhood vaccination programs, such as in Japan and the Republic of Korea. However, the lack of vaccine programs or insufficient coverage of populations in other endemic countries leaves many people susceptible to JEV. The aim of this study was to predict the distribution of Culex tritaeniorhynchus using ecological niche modeling. Methods/Principal Findings An ecological niche model was constructed using the Maxent program to map the areas with suitable environmental conditions for the Cx. tritaeniorhynchus vector. Program input consisted of environmental data (temperature, elevation, rainfall) and known locations of vector presence resulting from an extensive literature search and records from MosquitoMap. The statistically significant Maxent model of the estimated probability of Cx. tritaeniorhynchus presence showed that the mean temperatures of the wettest quarter had the greatest impact on the model. Further, the majority of human Japanese encephalitis (JE) cases were located in regions with higher estimated probability of Cx. tritaeniorhynchus presence. Conclusions/Significance Our ecological niche model of the estimated probability of Cx. tritaeniorhynchus presence provides a framework for better allocation of vector control resources, particularly in locations where JEV vaccinations are unavailable. Furthermore, this model provides estimates of vector probability that could improve vector surveillance programs and JE control efforts. PMID:22724030

  11. Acyclovir resistance in herpes simplex virus type I encephalitis: a case report.

    Science.gov (United States)

    Bergmann, M; Beer, R; Kofler, M; Helbok, R; Pfausler, B; Schmutzhard, E

    2017-04-01

    Acyclovir resistance is rarely seen in herpes simplex virus (HSV) type I encephalitis. Prevalence rates vary between 0.5 % in immunocompetent patients (Christophers et al. 1998; Fife et al. 1994) and 3.5-10 % in immunocompromised patients (Stranska et al. 2005). We report a 45-year-old, immunocompetent (negative HIV antigen/antibody testing), female patient, without previous illness who developed-after a febrile prodromal stage-aphasia and psychomotor slowing. Cerebral magnetic resonance imaging (cMRI) showed right temporal and insular T2-hyperintense lesions with spreading to the contralateral temporal lobe. Cerebrospinal fluid (CSF) analysis yielded lymphocytic pleocytosis and elevated protein level. Polymerase chain reaction testing for HSV type I showed a positive result in repeat lumbar puncture. HSV type I encephalitis was diagnosed and intravenous acyclovir treatment was initiated (750 mg t.i.d.). Acyclovir treatment was intensified to 1000 mg t.i.d., due to clinical deterioration, ongoing pleocytosis and progression on cMRI 5 days after initiation of antiviral therapy. In parallel, acyclovir resistance testing showed mutation of thymidine kinase gene at position A156V prompting foscarnet therapy (60 mg t.i.d.). Patient's condition improved dramatically over 2 weeks. Acyclovir resistance is rare but should be considered in case of clinical worsening of patient's condition. To our knowledge, this is the first report of acyclovir resistance in HSV type I encephalitis of an immunocompetent and previously healthy patient in Austria.

  12. Molecular evidence for the occurrence of Japanese encephalitis virus genotype I and III infection associated with acute Encephalitis in Patients of West Bengal, India, 2010

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    Sarkar Arindam

    2012-11-01

    Full Text Available Abstract Background Japanese encephalitis virus (JEV, a mosquito-borne zoonotic pathogen, is the sole etiologic agent of Japanese Encephalitis (JE; a neurotropic killer disease which is one of the major causes of viral encephalitis worldwide with prime public health concern. JE was first reported in the state of West Bengal, India in 1973. Since then it is being reported every year from different districts of the state, though the vaccination has already been done. Therefore, it indicates that there might be either partial coverage of the vaccine or the emergence of mutated/new strain of JEV. Considering this fact, to understand the JEV genotype distribution, we conducted a molecular epidemiological study on a total of 135 serum/cerebrospinal fluid (CSF samples referred and/or collected from the clinically suspected patients with Acute encephalitis syndrome (AES, admitted in different district hospitals of West Bengal, India, 2010. Findings JEV etiology was confirmed in 36/135 (26.6% and 13/61 (21.3% 2–15 days’ febrile illness samples from AES cases by analyzing Mac-ELISA followed by RT-PCR test respectively. Phylogenetic analysis based on complete envelope gene sequences of 13 isolates showed the emergence of JEV genotype I (GI, co-circulating with genotype III (GIII. Conclusion This study represents the first report of JEV GI with GIII, co-circulating in West Bengal. The efficacy of the vaccine (derived from JEV GIII strain SA-14-14-2 to protect against emerging JEV GI needs careful evaluation. In future, JE outbreak is quite likely in the state, if this vaccine fails to protect sufficiently against GI of JEV.

  13. IC-51, an injectable vaccine for the prevention of Japanese encephalitis virus infection.

    Science.gov (United States)

    Jones, Taff

    2009-02-01

    The mosquito-borne Japanese encephalitis (JE) virus is the major etiological agent of viral encephalitis in children living in South-East Asia, causing comas, seizures and Parkinson's disease-like movement disorders. Travelers and military personnel visiting the region are also highly susceptible to the disease. As the population in South-East Asia increases, more land is irrigated to produce rice paddies (the ideal breeding habitat for mosquitoes), and pig breeding (a zoonotic host for mosquitoes) becomes more widespread. Given the exponential growth in tourism to the region and the globalization of business and commerce, an enhanced requirement for mass vaccination exists. In the West, the current licensed vaccine against JE, JE-VAX, has been highly effective; however, the use of mouse brain-derived virus has been linked to cases of acute disseminated encephalomyelitis. Intercell AG, under license from VaccGen International LLC, is developing IC-51, a formalin-inactivated vaccine derived from cell culture-based attenuated virus that has been adapted to grow in Vero cells (African green monkey kidney cells). In extensive clinical trials performed to date, IC-51 was safe, with mild to moderate adverse events reported. In terms of immunogenicity, IC-51 was highly effective, demonstrating rapid seroconversion rates and long-term maintenance of geometric mean titers that exceeded the protective titer. The results suggests that IC-51 is fully compliant with the stringent regulatory requirements set by the WHO, has an acceptable safety profile and is non-inferior to JE-VAX.

  14. Equine Arteritis Virus Does Not Induce Interferon Production in Equine Endothelial Cells: Identification of Nonstructural Protein 1 as a Main Interferon Antagonist

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    Yun Young Go

    2014-01-01

    Full Text Available The objective of this study was to investigate the effect of equine arteritis virus (EAV on type I interferon (IFN production. Equine endothelial cells (EECs were infected with the virulent Bucyrus strain (VBS of EAV and expression of IFN-β was measured at mRNA and protein levels by quantitative real-time RT-PCR and IFN bioassay using vesicular stomatitis virus expressing the green fluorescence protein (VSV-GFP, respectively. Quantitative RT-PCR results showed that IFN-β mRNA levels in EECs infected with EAV VBS were not increased compared to those in mock-infected cells. Consistent with quantitative RT-PCR, Sendai virus- (SeV- induced type I IFN production was inhibited by EAV infection. Using an IFN-β promoter-luciferase reporter assay, we subsequently demonstrated that EAV nsps 1, 2, and 11 had the capability to inhibit type I IFN activation. Of these three nsps, nsp1 exhibited the strongest inhibitory effect. Taken together, these data demonstrate that EAV has the ability to suppress the type I IFN production in EECs and nsp1 may play a critical role to subvert the equine innate immune response.

  15. Circulation of Japanese encephalitis virus in pigs and mosquito vectors within Can Tho city, Vietnam.

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    Johanna F Lindahl

    Full Text Available Japanese encephalitis virus (JEV is a mosquito-borne, zoonotic flavivirus causing encephalitis in humans and reproductive disorder in pigs. JEV is present in large parts of Asia, where urbanization is high. Households within and outside Can Tho city, South Vietnam, were selected to monitor circulation of JEV. A nested RT-PCR was established to detect the presence of JEV in mosquitoes whereas sera from pigs belonging to households within the province were analyzed for the presence of antibodies to JEV. A total of 7885 mosquitoes were collected and divided into 352 pools whereof seven were JEV-positive, six of which were collected within the city. Fragments from four pools clustered with JEV genotype III and three with genotype I. Of the 43 pigs sampled inside the city 100% had JEV antibodies. Our study demonstrates exposure to JEV in pigs, and co-circulation of JEV genotype I and III in mosquitoes within an urban environment in South Vietnam. Thus, although JEV has mainly been considered a rural disease, the potential for transmission in urban areas cannot be ignored.

  16. miR-124 attenuates Japanese encephalitis virus replication by targeting DNM2.

    Science.gov (United States)

    Yang, Songbai; Pei, Yue; Li, Xinyun; Zhao, Shuhong; Zhu, Mengjin; Zhao, Ayong

    2016-06-21

    Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus that causes acute viral encephalitis in humans. Pigs are important amplifier hosts of JEV. Emerging evidence indicates that host microRNAs (miRNAs) play key roles in modulating viral infection and pathogenesis. However, mechanistic studies delineating the roles of miRNAs in regulating host-JEV interactions remain scarce. In this study, we demonstrated that miR-124 inhibited JEV replication in porcine kidney epithelial PK15 cells. Furthermore, using bioinformatics tools, we identified dynamin2 (DNM2), a GTPase responsible for vesicle scission, as a target of miR-124. Small interfering RNA (siRNA) depletion studies inicated that dynamin2 was required for efficient JEV replication. We also demonstrated that upregulation of miR-124 expression corresponded to decreased expression of its target, DNM2, in the JEV-infected PK15 cells. Overall, these results suggest the importance of miR-124 in modulating JEV replication and provide a scientific basis for using cellular miRNAs in anti-JEV therapies.

  17. Circulation of Japanese Encephalitis Virus in Pigs and Mosquito Vectors within Can Tho City, Vietnam

    Science.gov (United States)

    Lindahl, Johanna F.; Ståhl, Karl; Chirico, Jan; Boqvist, Sofia; Thu, Ho Thi Viet; Magnusson, Ulf

    2013-01-01

    Japanese encephalitis virus (JEV) is a mosquito-borne, zoonotic flavivirus causing encephalitis in humans and reproductive disorder in pigs. JEV is present in large parts of Asia, where urbanization is high. Households within and outside Can Tho city, South Vietnam, were selected to monitor circulation of JEV. A nested RT-PCR was established to detect the presence of JEV in mosquitoes whereas sera from pigs belonging to households within the province were analyzed for the presence of antibodies to JEV. A total of 7885 mosquitoes were collected and divided into 352 pools whereof seven were JEV-positive, six of which were collected within the city. Fragments from four pools clustered with JEV genotype III and three with genotype I. Of the 43 pigs sampled inside the city 100% had JEV antibodies. Our study demonstrates exposure to JEV in pigs, and co-circulation of JEV genotype I and III in mosquitoes within an urban environment in South Vietnam. Thus, although JEV has mainly been considered a rural disease, the potential for transmission in urban areas cannot be ignored. PMID:23593520

  18. Genetic characterization of St. Louis encephalitis virus isolated from human in São Paulo, Brazil

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    Cecília Luiza Simões dos Santos

    2006-02-01

    Full Text Available The molecular characterization of SPH253157, a new strain of St. Louis encephalitis virus (SLEV, isolated in 2004 from the first case of human infection recognized in the state of São Paulo, Brazil, is reported. The patient, presenting a febrile illness without neurological involvement, was hospitalized as a probable case of dengue fever. Genomic RNA was isolated from the supernatant of C6/36 cells infected with acute phase-serum specimen of the patient and the envelope gene was amplified by reverse-transcription-polymerase chain reaction. The complete nucleotide sequence of the envelope gene of this isolate was directly sequenced from the amplified products and compared with other Brazilian and American SLEV strains. Phylogenetic analyses were carried out under maximum likelihood criterion with outgroups both included and excluded. Outgroups comprised four flavivirus of the Japanese encephalitis group. Phylogeny also included Bayesian analysis. The results indicated that the new SLEV isolate belongs to lineage III, being closely related to an Argentinean strain recovered from Culex sp. in 1979. It is concluded that there are at least 3 lineages of SLEV in Brazil.

  19. Construction and characterization of recombinant Japanese encephalitis virus carrying brainspecific miRNA target sequences

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    Wen-yuan CAO

    2014-08-01

    Full Text Available Objective To construct the recombinant Japanese encephalitis virus ( JEV carrying brain-specific miRNA targeting sequences. Methods The target sequences of brain-specific miR-124 and miR-125 were introduced into the infectious cDNA clone of JEV to generate recombinant plasmids based on reverse genetics technology. The recombinant plasmids were linearized with Xho Ⅰ and served as templates of transcription with SP6 RNA polymerase to generate infectious viral RNA. The RNA transcripts were then transfected into BHK-21 cells, and the supernatant was obtained after incubated at 37℃, 5% CO2 for 3 days. The cytopathic changes of BHK-21 cells inoculated with the supernatant were observed after one passage. The rescued viruses carrying miRNA target sequences were validated by RT-PCR, standard plaque forming test on BHK-21 cells and growth curves analysis. Results Two recombinant viruses carrying miR-124 or miR-125 target sequence were rescued, respectively. The insertion of miRNA target sequences was confirmed by DNA sequencing. The rescued viruses yielded similar plaque morphology and replication efficiency compared with wild type JEV. Conclusion The recombinant JEV containing brain-specific miRNA target sequences can be obtained by reverse genetics technique, which could be used in further studies of miRNA-mediated tissue-specific attenuation mechanism of JEV. DOI: 10.11855/j.issn.0577-7402.2014.06.01

  20. Mx Is Not Responsible for the Antiviral Activity of Interferon-α against Japanese Encephalitis Virus

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    Jing Zhou

    2017-01-01

    Full Text Available Mx proteins are interferon (IFN-induced dynamin-like GTPases that are present in all vertebrates and inhibit the replication of myriad viruses. However, the role Mx proteins play in IFN-mediated suppression of Japanese encephalitis virus (JEV infection is unknown. In this study, we set out to investigate the effects of Mx1 and Mx2 expression on the interferon-α (IFNα restriction of JEV replication. To evaluate whether the inhibitory activity of IFNα on JEV is dependent on Mx1 or Mx2, we knocked down Mx1 or Mx2 with siRNA in IFNα-treated PK-15 cells and BHK-21 cells, then challenged them with JEV; the production of progeny virus was assessed by plaque assay, RT-qPCR, and Western blotting. Our results demonstrated that depletion of Mx1 or Mx2 did not affect JEV restriction imposed by IFNα, although these two proteins were knocked down 66% and 79%, respectively. Accordingly, expression of exogenous Mx1 or Mx2 did not change the inhibitory activity of IFNα to JEV. In addition, even though virus-induced membranes were damaged by Brefeldin A (BFA, overexpressing porcine Mx1 or Mx2 did not inhibit JEV proliferation. We found that BFA inhibited JEV replication, not maturation, suggesting that BFA could be developed into a novel antiviral reagent. Collectively, our findings demonstrate that IFNα inhibits JEV infection by Mx-independent pathways.

  1. Molecular detection and genotyping of Japanese Encephalitis Virus in mosquitoes during a 2010 outbreak in the Republic of Korea

    Science.gov (United States)

    Seo, Hyun-Ji; Kim, Heung Chul; Klein, Terry A.; Ramey, Andrew M.; Lee, Ji-Hyee; Kyung, Soon-Goo; Park, Jee-Yong; Cho, In-Soo; Yeh, Jung-Yong

    2013-01-01

    Japanese encephalitis virus (JEV), a mosquito-borne zoonotic pathogen, is one of the major causes of viral encephalitis. To reduce the impact of Japanese encephalitis among children in the Republic of Korea (ROK), the government established a mandatory vaccination program in 1967. Through the efforts of this program only 0-7 (mean 2.1) cases of Japanese encephalitis were reported annually in the ROK during the period of 1984-2009. However, in 2010 there was an outbreak of 26 confirmed cases of Japanese encephalitis, including 7 deaths. This represented a >12-fold increase in the number of confirmed cases of Japanese encephalitis in the ROK as compared to the mean number reported over the last 26 years and a 3.7-fold increase over the highest annual number of cases during this same period (7 cases). Surveillance of adult mosquitoes was conducted during the 2010 outbreak of Japanese encephalitis in the ROK. A total of 6,328 culicine mosquitoes belonging to 12 species from 5 genera were collected at 6 survey sites from June through October 2010 and assayed by reverse-transcription polymerase chain reaction (RT-PCR) for the presence of JEV. A total of 34/371 pooled samples tested positive for JEV (29/121 Culex tritaeniorhynchus, 4/64 Cx. pipiens, and 1/26 Cx. bitaeniorhynchus) as confirmed by sequencing of the pre-membrane and envelope protein coding genes. The maximum likelihood estimates of JEV positive individuals per 1,000 culicine vectors for Cx. tritaeniorhynchus, Cx. pipiens, and Cx. bitaeniorhynchus were 11.8, 5.6, and 2.8, respectively. Sequences of the JEV pre-membrane and envelope protein coding genes amplified from the culicine mosquitoes by RT-PCR were compared with those of JEV genotypes I-V. Phylogenetic analyses support the detection of a single genotype (I) among samples collected from the ROK in 2010.

  2. All subgenomic mRNAs of equine arteritis virus contain a common leader sequence.

    OpenAIRE

    de Vries, A A; Chirnside, E D; Bredenbeek, P J; Gravestein, L A; Horzinek, M C; Spaan, W J

    1990-01-01

    During the replication of equine arteritis virus (EAV) six subgenomic mRNAs are synthesized. We present evidence that the viral mRNAs form a 3'-coterminal nested set and contain a common leader sequence of 208 nucleotides which is encoded by the 5'-end of the genome. The leader is joined to the bodies of mRNA 5 and 6 at positions defined by the sequence 5' UCAAC 3'. The part of the leader sequence flanking the UCAAC motif is very similar to the 5'-splice site of the Tetrahymena pre-rRNA. A po...

  3. Establishment of an analyzing method for a Japanese encephalitis virus neutralization test in Vero cells.

    Science.gov (United States)

    Abe, Motoharu; Kuzuhara, Syoji; Kino, Yoichiro

    2003-05-16

    We established a 50% plaque reduction analyzing method of neutralizing antibody for human serum to Japanese encephalitis virus (JEV) in Vero cells, called the '3 points least-squares regression method' (3LSRM). Our method shows a high correlation with the chick embryo cell method (the current standard method for human serum), using the chart method established by the National Institute of Infectious Diseases of Japan, which is an equation made with retrospective data obtained with the 50% plaque reduction method as a standard measurement method for neutralizing antibody titers to JEV. Our new method is much simpler and more reliable than the current method in that it uses an established cell line, Vero cells, and its results are computed by the 3LSRM.

  4. Correlation of in vivo neuroimaging abnormalities with postmortem human immunodeficiency virus encephalitis and dendritic loss

    DEFF Research Database (Denmark)

    Archibald, Sarah L.; Masliah, Eliezer; Fennema-Notestine, Christine

    2004-01-01

    previous studies have linked brain viral levels to these alterations, other neuropathological mechanisms might also contribute to them. OBJECTIVE: To examine the relationship between findings on premortem magnetic resonance images and postmortem neuropathologic evidence of human immunodeficiency virus (HIV......) encephalitis and neurodegeneration. DESIGN: Morphometric analysis of magnetic resonance imaging in seropositive cases with matched seronegative controls, and the correlation of these volumes to neuropathological measures in autopsied seropositive cases. SETTING: University of California, San Diego, HIV...... Neurobehavioral Research Center. SUBJECTS: Twenty-one seropositive subjects studied at autopsy and 19 seronegative cases. MAIN OUTCOME MEASURES: In vivo structural magnetic resonance imaging data analyzed by quantitative methods, with comparison of volumes from magnetic resonance imaging and neuropathological...

  5. Focal encephalitis following varicella-zoster virus reactivation without rash in a healthy immunized young adult.

    Science.gov (United States)

    Halling, Geoffrey; Giannini, Caterina; Britton, Jeffrey W; Lee, Ricky W; Watson, Robert E; Terrell, Christine L; Parney, Ian F; Buckingham, Erin M; Carpenter, John E; Grose, Charles

    2014-09-01

    Herein we describe an episode of focal varicella-zoster virus (VZV) encephalitis in a healthy young man with neither rash nor radicular pain. The symptoms began with headaches and seizures, after which magnetic resonance imaging detected a single hyperintense lesion in the left temporal lobe. Because of the provisional diagnosis of a brain tumor, the lesion was excised and submitted for pathological examination. No tumor was found. But the tissue immunostained positively for VZV antigens, and wild-type VZV sequences were detected. In short, this case represents VZV reactivation, most likely in the trigeminal ganglion, in the absence of clinical herpes zoster. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  6. A first note on Japanese encephalitis virus isolation from Culex quinquefasciatus Say in Northern West Bengal.

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    V. Thenmozhi

    2014-03-01

    Full Text Available Japanese encephalitis (JE is endemic in many parts of India including the state of West Bengal. In West Bengal, the first major outbreaks of JE occurred in the districts of Bankura and Burdwan in 1973. The Culex vishnui subgroup of mosquitoes has been implicated as major vectors of JE. However in India, JE virus (JEV has been isolated from 16 species of mosquitoes. During September 2011, JE cases were reported from four districts -Jalpaiguri, Darjeeling, Dinajpur and Cooch Behar of West Bengal (North. Adult mosquitoes were collected, identified, pooled and screened for JEV using antigen capture ELISA. Out of 279 mosquito pools tested, one pool of Cx. pseudovishnui and three pools of Cx. quinquefasciatus were found positive for JEV. The ELISA positive pools were further confirmed as JEV by insect bioassay (Toxo-IFA. Two pools of Cx. quinquefasciatus were confirmed as JEV. This represents the first report of JEV isolation from Cx. quinquefasciatus in West Bengal.

  7. Molecular epidemiology of Japanese encephalitis virus circulating in South Korea, 1983-2005

    Science.gov (United States)

    2010-01-01

    We sequenced the envelope (E) gene of 17 strains of the Japanese encephalitis virus (JEV) isolated in South Korea in 1983-2005 and compared the sequences with those from previously reported strains. Our results show the remarkable genetic stability of the E gene sequence in Korean JEV strains. Five pairs of E gene sequences from 10 Korean strains were identical, despite geographical differences and a maximum five-year time span. Sequence comparisons with other Asian strains revealed that the Korean strains are closely related to those from China, Japan, and Vietnam. Genotype 3 strains were predominant in Korea before 1993, when genotype 1 strain K93A07 was first isolated. The two genotypes were detected simultaneously in 1994 but since then, only genotype 1 has been isolated in South Korea. Thus, the genotype change occurred according to the year of isolation rather than the geographical origin. PMID:20546562

  8. [Generation of Japanese Encephalitis Virus-like Particle Vaccine and Preliminary Evaluation of Its Protective Efficiency].

    Science.gov (United States)

    Zhang, Yanfang; Du, Ruikun; Huang, Shaomei; Zhang, Tao; Liu, Jinliang; Zhu, Bibo; Wang, Hualin; Deng, Fei; Cao, Shengbo

    2016-03-01

    The cDNA fragment of JEV prME gene was cloned into the baculovirus shuttle vector (bacmid) to construct a recombinant baculovirus vector, defined as AcBac-prME. Then the recombinant baculovirus Ac-prME was obtained by transfecting Sf9 cells with AcBac-prME. Western blot analysis and immunofluorescence results indicated that both prM and E proteins were efficiently expressed in Sf9 cells. Electron microscopy suggested that prME was assembled into JEV-VLPs. To further evaluate the potential of JEV-VLPs as vaccine, the mice were immunized with JEV-VLPs and then challenged with lethal JEV. The results of mice survival and pathological changes demonstrated that the JEV-VLPs performed complete protection against JEV-P3 strain and relieved pathological changes in the mice brain significant. This study suggest that JEV-VLPs would be a potential vaccine for Japanese encephalitis virus.

  9. Prevalence of antibodies to Japanese encephalitis virus among pigs in Bali and East Java, Indonesia, 2008.

    Science.gov (United States)

    Yamanaka, Atsushi; Mulyatno, Kris Cahyo; Susilowati, Helen; Hendrianto, Eryk; Utsumi, Takako; Amin, Mochamad; Lusida, Maria Inge; Soegijanto, Soegeng; Konishi, Eiji

    2010-01-01

    Japanese encephalitis virus (JEV) is a fatal disease in Asia. Pigs are considered to be the effective amplifying host for JEV in the peridomestic environment. Bali Island and Java Island in Indonesia provide a model to assess the effect of pigs on JEV transmission, since the pig density is nearly 100-fold higher in Bali than Java, while the geographic and climatologic environments are equivalent in these areas. We surveyed antibodies to JEV among 123 pigs in Mengwi (Bali) and 96 pigs in Tulungagung (East Java) in 2008 by the hemagglutination-inhibition (HAI) test. Overall prevalences were 49% in Bali and 6% in Java, with a significant difference between them (P Java. In addition, 2-mercaptoethanol-sensitive antibodies were found only from Bali samples. Further, the average HAI antibody titer obtained from positive samples was significantly higher in Bali (1:52) than Java (1:10; P Java.

  10. Identification of Suitable Areas for African Horse Sickness Virus Infections in Spanish Equine Populations.

    Science.gov (United States)

    Sánchez-Matamoros, A; Sánchez-Vizcaíno, J M; Rodríguez-Prieto, V; Iglesias, E; Martínez-López, B

    2016-10-01

    African horse sickness (AHS) is one of the most important vector-borne viral infectious diseases of equines, transmitted mainly by Culicoides spp. The re-emergence of Culicoides-borne diseases in Europe, such as the recent bluetongue (BT) or Schmallenberg outbreaks, has raised concern about the potential re-introduction and further spread of AHS virus (AHSV) in Europe. Spain has one of the largest European equine populations. In addition, its geographical, environmental and entomological conditions favour AHSV infections, as shown by the historical outbreaks in the 1990s. The establishment of risk-based surveillance strategies would allow the early detection and rapid control of any potential AHSV outbreak. This study aimed to identify the areas and time periods that are suitable or at high risk for AHS occurrence in Spain using a GIS-based multicriteria decision framework. Specifically risk maps for AHS occurrence were produced using a weighted linear combination of the main risk factors of disease, namely extrinsic incubation period, equine density and distribution of competent Culicoides populations. Model results revealed that the south-western and north-central areas of Spain and the Balearic Islands are the areas at the highest risk for AHSV infections, particularly in late summer months. Conversely, Galicia, Castile and Leon and La Rioja can be considered as low-risk regions. This result was validated with historical AHS and BT outbreaks in Spain, and with the Culicoides vector distribution area. The model results, together with current Spanish equine production features, should provide the foundations to design risk-based and more cost-effective surveillance strategies for the early detection and rapid control potential of AHS outbreaks in Spain. © 2014 Blackwell Verlag GmbH.

  11. Transient widespread cortical and splenial lesions in acute encephalitis/encephalopathy associated with primary Epstein–Barr virus infection

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    Shuo Zhang

    2016-01-01

    Full Text Available Infection with Epstein–Barr virus (EBV is very common and usually occurs in childhood or early adulthood. Encephalitis/encephalopathy is an uncommon but serious neurological complication of EBV. A case of EBV-associated encephalitis/encephalopathy with involvement of reversible widespread cortical and splenial lesions is presented herein. An 8-year-old Chinese girl who presented with fever and headache, followed by seizures and drowsiness, was admitted to the hospital. Magnetic resonance imaging revealed high signal intensities on diffusion-weighted imaging in widespread cortical and splenial lesions. The clinical and laboratory examination results together with the unusual radiology findings suggested acute encephalitis/encephalopathy due to primary EBV infection. After methylprednisolone pulse therapy together with ganciclovir, the patient made a full recovery without any brain lesions. The hallmark clinical–radiological features of this patient included severe encephalitis/encephalopathy at onset, the prompt and complete recovery, and rapidly reversible widespread involvement of the cortex and splenium. Patients with EBV encephalitis/encephalopathy who have multiple lesions, even with the widespread involvement of cortex and splenium of the corpus callosum, may have a favorable outcome with complete disappearance of all brain lesions.

  12. Construction and immune efficacy of recombinant pseudorabies virus expressing PrM-E proteins of Japanese encephalitis virus genotype І.

    Science.gov (United States)

    Qian, Ping; Zhi, Xianwei; Wang, Bo; Zhang, Huawei; Chen, Huanchun; Li, Xiangmin

    2015-12-10

    Japanese encephalitis (JE) is an arboviral disease with high case fatality rates and neurologic or psychiatric sequelae among survivors in Asia, western Pacific countries and northern Australia. Japanese encephalitis virus (JEV) is the cause of JE and the emergence of genotype І (GI) JEV has displaced genotype III (GIII) as the dominant strains circulating in some Asian regions. The currently available JE vaccines are safe and effective in preventing this disease, but they are developed based on the GIII JEV strains. The recombinant virus PRV TK(-)/gE(-)/PrM-E(+) which expressed the premembrane (prM) and envelope (E) proteins of JEV SX09S-01 strain (genotype I, GI) was constructed by homologous recombination between the genome of PRV TK(-)/gE(-)/LacZ(+) digested with EcoRI and plasmid pIE-CAG-PrM-E-BGH. Expression of JEV PrM and E proteins was analyzed by Western blot analysis. Immune efficacy of PRV TK(-)/gE(-)/PrM-E(+) was further evaluated in mouse model. A recombinant pseudorabies virus (PRV TK(-)/gE(-)/PrM-E(+)) was successfully constructed. Mice experiments showed that PRV TK(-)/gE(-)/PrM-E(+) could induce a high level of ELISA antibodies against PRV and JEV, as well as high titer of PRV neutralizing antibodies. After challenge with 1 × 10(7) PFU virulent JEV SX09S-01 strain, the time of death was delayed and the survival rate was improved in PRV TK(-)/gE(-)/PrM-E(+) vaccinated mice. PRV TK(-)/gE(-)/PrM-E(+) is a potential vaccine candidate against PRV and JEV GI infection in the future.

  13. Minocycline differentially modulates macrophage mediated peripheral immune response following Japanese encephalitis virus infection.

    Science.gov (United States)

    Dutta, Kallol; Mishra, Manoj Kumar; Nazmi, Arshed; Kumawat, Kanhaiya Lal; Basu, Anirban

    2010-11-01

    Japanese encephalitis virus (JEV) is a neurotropic flavivirus that is the causative agent of a major mosquito-borne encephalitis in the world. Evasion of peripheral immune system facilitates the entry of the virus into the central nervous system (CNS) where it causes extensive neuronal inflammatory damage that leads to death or severe neuropschychiatric sequel in survivors. It has been proposed that after entry into the body, the virus is carried into the CNS by peripheral immune cells that act as Trojan horses. In this study we investigate whether macrophages can be considered as such a Trojan horse. We also investigate the role of minocycline, a synthetic tetracycline, in such processes. Minocycline has been found to be broadly protective in neurological disease models featuring inflammation and cell death but there has been no report of it having any modulatory role in peripheral macrophage-mediated immune response against viral infection. Persistence of internalized virus within macrophages was visualized by immunofluorescent staining. Cytotoxicity assay revealed that there was no significant cell death after 24 h and 72 h infection with JEV. Proinflammatory cytokine levels were elevated in cells that were infected with JEV but it was abrogated following minocycline treatment. Reactive oxygen species level was also increased after JEV infection. Nitric oxide level was found to increase after 72 h post infection but remained unchanged after 24h. The cellular levels of signaling molecules such as PI3 kinase, phophoAkt and phospho p38MAP kinase were found to be altered after JEV infection and minocycline treatment. JEV infection also affected the VEGF-MMP pathway. Increased activity of MMP-9 was detected from JEV-infected macrophage culture supernatants after 72 h; minocycline treatment resulted in reduced activity. Thus it seems that minocycline dampens peripheral immune reactions by decreasing proinflammatory cytokine release from infected macrophages and the

  14. A Bayesian Belief Network for Murray Valley encephalitis virus risk assessment in Western Australia.

    Science.gov (United States)

    Ho, Soon Hoe; Speldewinde, Peter; Cook, Angus

    2016-01-28

    Murray Valley encephalitis virus (MVEV) is a clinically important virus in Australia responsible for a number of epidemics over the past century. Since there is no vaccine for MVEV, other preventive health measures to curtail its spread must be considered, including the development of predictive risk models and maps to help direct public health interventions. This article aims to support these approaches by presenting a model for assessing MVEV risk in Western Australia (WA). A Bayesian Belief Network (BBN) for assessing MVEV risk was developed and used to quantify and map disease risks in WA. The model combined various abiotic, biotic, and anthropogenic factors that might affect the risk of MVEV into a predictive framework, based on the ecology of the major mosquito vector and waterbird hosts of MVEV. It was further refined and tested using retrospective climate data from 4 years (2000, 2003, 2009, and 2011). Implementing the model across WA demonstrated that it could predict locations of human MVEV infection and sentinel animal seroconversion in the 4 years tested with some degree of accuracy. In general, risks are highest in the State's north and lower in the south. The model predicted that short-term climate change, based on the Intergovernmental Panel on Climate Change's A1B emissions scenario, would decrease MVEV risks in summer and autumn, largely due to higher temperatures decreasing vector survival. To our knowledge, this is the first model to use a BBN to quantify MVEV risks in WA. The models and maps developed here may assist public health agencies in preparing for and managing Murray Valley encephalitis in the future. In its current form, the model is knowledge-driven and based on the analysis of potential risk factors that affect the dynamics of MVEV using retrospective data. Further work and additional testing should be carried out to test its validity in future years.

  15. NK Cell Responses to Human Tick-Borne Encephalitis Virus Infection.

    Science.gov (United States)

    Blom, Kim; Braun, Monika; Pakalniene, Jolita; Lunemann, Sebastian; Enqvist, Monika; Dailidyte, Laura; Schaffer, Marie; Lindquist, Lars; Mickiene, Aukse; Michaëlsson, Jakob; Ljunggren, Hans-Gustaf; Gredmark-Russ, Sara

    2016-10-01

    Tick-borne encephalitis virus (TBEV) is a flavivirus that is transferred to humans by infected ticks. The virus causes tick-borne encephalitis, a severe infection of the CNS with a high risk for long-lasting sequelae. Currently, no treatment exists for the disease. Understanding the cellular immune response to this infection is important to gain further understanding into the pathogenesis, treatment, and prevention of the disease. NK cells are known to participate in the control of viral infections. We performed a longitudinal analysis of the human NK cell response to TBEV infection in a cohort of infected individuals from the onset of severe clinical symptoms to the convalescence phase. NK cell activation, as measured by expression of Ki67, was apparent at the time of hospitalization. By 3 wk after hospitalization, it decreased to levels seen in healthy controls. Concomitant with the increase in NK cell activation, augmented levels of IL-12, IL-15, IL-18, IFN-γ, and TNF were detected in patient plasma. This TBEV-induced NK cell activation was restricted predominantly to differentiated CD57(+)CD56(dim) NK cells. Functionally, CD56(dim) NK cells responded poorly to target cells at the time of hospitalization, but they recovered functional capacity to control levels during the convalescent phase. In contrast, the responsiveness of NK cells to cytokine stimulation remained intact throughout the disease. These findings demonstrate that NK cells respond to TBEV infection with characteristics that are distinct from those of other human viral infections and provide insights into the NK cell response to clinical TBEV infection. Copyright © 2016 by The American Association of Immunologists, Inc.

  16. Partial Characterization of Tick-Borne Encephalitis Virus Isolates from Ticks of Southern Ukraine.

    Science.gov (United States)

    Yurchenko, Oksana O; Dubina, Dmytro O; Vynograd, Nataliya O; Gonzalez, Jean-Paul

    2017-08-01

    Tick-borne encephalitis (TBE) is the most common tick-borne viral infection in Eurasia; thousands of human cases are annually reported from several European countries. Several tick species are vectors of the tick-borne encephalitis virus (TBEV), while TBE appears to be spreading from the Eurasian continent westward to Europe. Fifteen study sites were chosen from five territories of southern Ukraine, including Odessa, Mykolaiv, Kherson Oblast, the Autonomous Republic of Crimea, and Sevastopol. Tick collection was performed in spring season of three consecutive years (1988-1990) using either flagging technique or direct collection of specimens feeding on cattle. A total of 15,243 tick imagoes and nymphs were collected from nine species, including Dermacentor marginatus, D. reticulatus, Haemaphysalis parva, H. punctata, Hyalomma marginatum, Ixodes ricinus, Rhipicephalus bursa, R. rossicus, and R. sanguineus, pooled in 282 monospecific samples. Supernatant of grinded pool was used for inoculation to suckling mice for virus isolation. Eight TBEV isolates were identified from ticks among six study sites. Ticks showed a minimum infection rate from 0.11% to 0.81%. Phylogenetic analysis of the envelope (E) protein gene of seven isolates, assigned all to the European subtype (TBEV-Eu) showing a maximum identity of 97.17% to the "Pan" TBEV-Eu reference strain. Compared to 104 TBEV-Eu isolates they clustered within the same clade as the Pan reference strain and distinguished from other TBEV-Eu isolates. Amino acid sequence analysis of the South Ukrainian TBEV-Eu isolates revealed the presence of four amino acid substitutions 67 (N), 266 (R), 306 (V), and 407 (R), in the ectodomains II and III and in the stem-anchor region of the E protein gene. This study confirmed TBEV-Eu subtype distribution in the southern region of Ukraine, which eventually overlaps with TBEV-FE (Far Eastern subtype) and TBEV-Sib (Siberian subtype) domains, showing the heterogeneity of TBEV circulating in

  17. Reproduction of Venezulean Equine Encephalomyelitis Virus at Low Ionic Strength

    Science.gov (United States)

    1975-02-28

    using electron microscopy, that Sthe formation of nucleoides of VEE virus occurs near vacuoles formed in the cytoplasm of infected cells ard the...formation of supercapsides as a result of the nucleoide gemmation on the walls of cytoplasmic membranes. The problem posed for this study included an... nucleoides . A comparison of the position of the structures in the gradient with the sedimentation * of the virion ribonucleoproteid secreted from the

  18. Epidemiology and Genetic Characterization of H3N8 Equine Influenza Virus Responsible for Clinical Disease in Algeria in 2011.

    Science.gov (United States)

    Laabassi, F; Lecouturier, F; Amelot, G; Gaudaire, D; Mamache, B; Laugier, C; Legrand, L; Zientara, S; Hans, A

    2015-12-01

    An outbreak of equine influenza (EI) was reported in Algeria between May and July, 2011. The outbreak started in Tiaret, in west province of Algeria, and spread to the other parts of the country affecting almost 900 horses in many provinces. The population studied was composed of 325 horses from different groups of age. Clinical sign expression was age dependent. Indeed, a morbidity rate of 14.9% was observed in horses under 15 months old and a rate of 4.95% in horses over 8 years old. Interestingly, the morbidity rate raised sharply to reach 100% in horses aged between 18 months and 7 years. The virus (H3N8) was detected in nasopharyngeal swabs (n = 11) from non-vaccinated horses using a qRT-PCR targeting a portion of the gene encoding the matrix protein (M). The virus isolates were identified as H3N8 by sequencing the haemagglutinin (HA) and neuraminidase (NA) genes and were named from A/equine/Tiaret/1/2011 to A/equine/Tiaret/10/2011. Alignment of HA1 amino acid sequence confirmed that viruses belong to Clade 2 of the Florida sublineage in the American lineage. Moreover, they are closely related to A/equine/Yokohama/aq13/2010, A/equine/Eyragues/1/2010, A/equine/Bokel/2011 and A/equine/Lichtenfeld/2012. Our data indicate that this strain was also circulating in the European horse population in 2010, 2011 and 2012. © 2014 Blackwell Verlag GmbH.

  19. Molecular Basis of the Divergent Immunogenicity of Two Pediatric Tick-Borne Encephalitis Virus Vaccines.

    Science.gov (United States)

    Beck, Yvonne; Fritz, Richard; Orlinger, Klaus; Kiermayr, Stefan; Ilk, Reinhard; Portsmouth, Daniel; Pöllabauer, Eva-Maria; Löw-Baselli, Alexandra; Hessel, Annett; Kölch, Doris; Howard, M Keith; Barrett, P Noel; Kreil, Thomas R

    2015-12-09

    Studies evaluating the immunogenicity of two pediatric tick-borne encephalitis virus (TBEV) vaccines have reported contradictory results. These vaccines are based on two different strains of the European TBEV subtype: FSME-Immun Junior is based on the Neudörfl (Nd) strain, whereas Encepur Children is based on the Karlsruhe (K23) strain. The antibody (Ab) response induced by these two vaccines might be influenced by antigenic differences in the envelope (E) protein, which is the major target of neutralizing antibodies. We used an established hybrid virus assay platform to compare the levels of induction of neutralizing antibodies against the two vaccine virus strains in children aged 1 to 11 years who received two immunizations with FSME-Immun Junior or Encepur Children. The influence of amino acid differences between the E proteins of the Nd and K23 vaccine strains was investigated by mutational analyses and three-dimensional computer modeling. FSME-Immun Junior induced 100% seropositivity and similar neutralizing antibody titers against hybrid viruses containing the TBEV E protein of the two vaccine strains. Encepur Children induced 100% seropositivity only against the hybrid virus containing the E protein of the homologous K23 vaccine strain. Antibody responses induced by Encepur Children to the hybrid virus containing the E protein of the heterologous Nd strain were substantially and significantly (P virus. Structure-based mutational analyses of the TBEV E protein indicated that this is due to a mutation in the DI-DII hinge region of the K23 vaccine strain E protein which may have occurred during production of the vaccine seed virus and which is not present in any wild-type TBE viruses. Our data suggest that there are major differences in the abilities of two European subtype pediatric TBEV vaccines to induce antibodies capable of neutralizing heterologous TBEV strains. This is a result of a mutation in the DI-DII hinge region of the E protein of the K23

  20. A Phase-1 Clinical Trial of a DNA Vaccine for Venezuelan Equine Encephalitis Delivered by Intramuscular or Intradermal Electroporation

    Science.gov (United States)

    2016-05-25

    concerns associated with pWRG/VEE or delivery method identified during the Phase 1 study. 3.4. Tolerability of Vaccine Procedures To assess the...results of the Phase I clinical study of EP-mediated pWRG/VEE delivery demonstrate an acceptable safety and reactogenicity profile for the DNA vaccine...11] Hooper JW, Moon JE, Paolino KM, Newcomer R, McLain DE, Josleyn M, et al. A Phase 1 clinical trial of Hantaan virus and Puumala virus M-segment

  1. [Prevalence of antibodies against Tick-Borne Encephalitis virus in dogs from Saxony, Germany].

    Science.gov (United States)

    Balling, Anneliese; Beer, Martin; Gniel, Dieter; Pfeffer, Martin

    2015-01-01

    Tick-borne encephalitis (TBE) is the most important tick-transmitted viral disease in Europe and is caused by the TBE virus (TBEV), a member of the Flaviviridae family. In Germany, the vast majority of human TBE cases occurs in the south in so-called risk areas. However, in areas with only sporadic TBE cases, the respective risk assessment is hard to achieve. We therefore intend to use the prevalence of antibodies against TBEV in dogs as an indicator to trace such TBE endemic areas. Between August 2012 and March 2014, a total of 331 blood sera were collected from dogs all over Saxony, which hadn't left the state for the past five years. For the detection of antibodies against TBE-virus a commercial ELISA was used. Ten sera with positive or borderline ELISA results were retested by serum neutralization test. All seven ELISA-positive serum samples could be verified to contain TBE-virus-specific antibodieswith SNT titres between 1:15 and more than 1:40. We therefore found 2.1% seroprevalence in our samples. We conclude, that dogs can very well be used as sentinels, especially in areas with only sporadic TBE cases, although larger sample sizes are desired.

  2. Differential Infectivities among Different Japanese Encephalitis Virus Genotypes in Culex quinquefasciatus Mosquitoes.

    Science.gov (United States)

    Huang, Yan-Jang S; Hettenbach, Susan M; Park, So Lee; Higgs, Stephen; Barrett, Alan D T; Hsu, Wei-Wen; Harbin, Julie N; Cohnstaedt, Lee W; Vanlandingham, Dana L

    2016-10-01

    During the last 20 years, the epidemiology of Japanese encephalitis virus (JEV) has changed significantly in its endemic regions due to the gradual displacement of the previously dominant genotype III (GIII) with clade b of GI (GI-b). Whilst there is only limited genetic difference distinguishing the two GI clades (GI-a and GI-b), GI-b has shown a significantly wider and more rapid dispersal pattern in several regions in Asia than the GI-a clade, which remains restricted in its geographic distribution since its emergence. Although previously published molecular epidemiological evidence has shown distinct phylodynamic patterns, characterization of the two GI clades has only been limited to in vitro studies. In this study, Culex quinquefasciatus, a known competent JEV mosquito vector species, was orally challenged with three JEV strains each representing GI-a, GI-b, and GIII, respectively. Infection and dissemination were determined based on the detection of infectious viruses in homogenized mosquitoes. Detection of JEV RNA in mosquito saliva at 14 days post infection indicated that Cx. quinquefasciatus can be a competent vector species for both GI and GIII strains. Significantly higher infection rates in mosquitoes exposed to the GI-b and GIII strains than the GI-a strain suggest infectivity in arthropod vectors may lead to the selective advantage of previously and currently dominant genotypes. It could thus play a role in enzootic transmission cycles for the maintenance of JEV if this virus were ever to be introduced into North America.

  3. North American Birds as Potential Amplifying Hosts of Japanese Encephalitis Virus

    Science.gov (United States)

    Nemeth, Nicole; Bosco-Lauth, Angela; Oesterle, Paul; Kohler, Dennis; Bowen, Richard

    2012-01-01

    Japanese encephalitis virus (JEV) is an emerging arbovirus, and inter-continental spread is an impending threat. The virus is maintained in a transmission cycle between mosquito vectors and vertebrate hosts, including birds. We detected variation in interspecies responses among North American birds to infection with strains of two different JEV genotypes (I and III). Several native North American passerine species and ring-billed gulls had the highest average peak viremia titers after inoculation with a Vietnamese (genotype I) JEV strain. Oral JEV shedding was minimal and cloacal shedding was rarely detected. The majority of birds, both viremic (72 of 74; 97.3%) and non-viremic (31 of 37; 83.8%), seroconverted by 14 days post-inoculation and West Nile virus-immune individuals had cross-protection against JEV viremia. Reservoir competence and serologic data for a variety of avian taxa are important for development of JEV surveillance and control strategies and will aid in understanding transmission ecology in the event of JEV expansion to North America. PMID:22927494

  4. Neuro-Immune Mechanisms in Response to Venezuelan equine encephalitis Virus Infection

    Science.gov (United States)

    2000-05-01

    pregnant women infected with VEE frequently spontaneously abort or the pregnancy ends in an intrauterine death (Casamassima et al., 1987, Weaver et...Homozygous TNFR -/- mice were resistant to lethal challenges of LPS, yet were susceptible to Listeria monocytogenes infection (Pfeffer et al., 1993). TNF-α...necrosis factor receptor are resistant to endotoxic shock, yet succumb to L. monocytogenes infection. Cell, 73, 457-67. Phelps, G. (1971) Vee in

  5. Self Amplifying RNA Vaccines for Venezuelan Equine Encephalitis Virus Induce Robust Protective Immunogenicity in Mice

    Science.gov (United States)

    2017-09-18

    Dupuy,b Clayton W. Beard,a,1 Carolyn M. Six,b Connie S. 3 Schmaljohn,b Peter Mason,c,2 Andrew J. Geall,a,3 Jeffery B. Ulmer,a and Dong Yua 4 a GSK...Annu Rev 698 Microbiol. 2001;55:235-53. 699 [2] Pittman PR, Makuch RS, Mangiafico JA, Cannon TL, Gibbs PH, Peters CJ. Long-term 700 duration of... Reed DS, Lind CM, Lackemeyer MG, Sullivan LJ, Pratt WD, Parker MD. Genetically 705 engineered, live, attenuated vaccines protect nonhuman primates

  6. Pathogenesis of Eastern Equine Encephalitis Virus in Mice and Development of a Second Generation Vaccine

    Science.gov (United States)

    2012-01-31

    were noted in the left foot until 1 dpi when there was scattered single cell death. However, by 2 dpi, there was mild to moderate cellulitis 71...cell death (apoptosis), cellulitis , and myocyte degeneration, necrosis and regeneration were noted in most mice, to varying degrees, in the left foot

  7. Pathogenesis of Aerosolized Eastern Equine Encephalitis Virus Infection in Guinea Pigs

    Science.gov (United States)

    2009-01-01

    MN) indicated a mass median aer- odynamic diameter ( MMAD ) of 1.0 μm and geometric standard deviation (σg) of 1.3 for the aerosols generated by the...initiation of disease. Larger aero- sol particles of EEEV with a MMAD of > 6 μm would be expected to deposit more in the upper respiratory tract

  8. Tunicamycin Enhances Neuroinvasion and Pathogenicity in Mice with Venezuelan Equine Encephalitis Virus

    Science.gov (United States)

    2003-01-01

    and hemorrhage, lymphoid necrosis, hepatocellular degeneration, and interstitial pneumonia.12 CNS changes include meningoencephalitis and myelitis...and humans with VEE exhibit meningoencephalitis characterized by cellular infiltrates in the meninges and perivascular spaces.12, 15, 16, 28 These...blood brain barrier (BBB) appear important. For example, external factors such as gram-negative bacteria or lipopolysaccharide (LPS) alone induce

  9. Comprehensive Mapping Antigenic Epitopes of NS1 Protein of Japanese Encephalitis Virus with Monoclonal Antibodies.

    Directory of Open Access Journals (Sweden)

    Rong-Hong Hua

    Full Text Available Japanese encephalitis virus (JEV non-structural protein 1 (NS1 contributes to virus replication and elicits protective immune responses during infection. JEV NS1-specific antibody responses could be a target in the differential diagnosis of different flavivirus infections. However, the epitopes on JEV NS1 are poorly characterized. The present study describes the full mapping of linear B-cell epitopes in JEV NS1. We generated eleven NS1-specific monoclonal antibodies from mice immunized with recombinant NS1. For epitope mapping of monoclonal antibodies, a set of 51 partially-overlapping peptides covering the entire NS1 protein were expressed with a GST-tag and then screened using monoclonal antibodies. Through enzyme-linked immunosorbent assay (ELISA, five linear epitope-containing peptides were identified. By sequentially removing amino acid residues from the carboxy and amino terminal of peptides, the minimal units of the five linear epitopes were identified and confirmed using monoclonal antibodies. Five linear epitopes are located in amino acids residues (5AIDITRK(11, (72RDELNVL(78, (251KSKHNRREGY(260, (269DENGIVLD(276, and (341DETTLVRS(348. Furthermore, it was found that the epitopes are highly conserved among JEV strains through sequence alignment. Notably, none of the homologous regions on NS1 proteins from other flaviviruses reacted with the MAbs when they were tested for cross-reactivity, and all five epitope peptides were not recognized by sera against West Nile virus or Dengue virus. These novel virus-specific linear B-cell epitopes of JEV NS1 would benefit the development of new vaccines and diagnostic assays.

  10. Monoclonal antibodies to equine IgM improve the sensitivity of West Nile virus-specific IgM detection in horses.

    Science.gov (United States)

    Wagner, Bettina; Glaser, Amy; Hillegas, Julia M; Erb, Hollis; Gold, Carvel; Freer, Heather

    2008-03-15

    West Nile virus (WNV) is a zoonotic pathogen of global importance. In horses with neurological signs, detection of WNV-specific immunoglobulin M (IgM) in serum is widely used to identify clinical cases of WNV encephalitis. Here, we describe the development of two monoclonal antibodies (mAbs) to equine IgM which were used in a WNV IgM-specific enzyme-linked immunosorbent assay (ELISA). Their performance was compared to an established assay based on polyclonal anti-IgM. Check test serum samples from the National Veterinary Service Laboratory (NVSL) were used to evaluate the performance of the three anti-IgM antibodies. The anti-IgM 1-22 mAb correctly identified all NVSL samples. Both the polyclonal antibody and monoclonal anti-IgM 2B-63 identified eight out of ten samples correctly. The three assays were then compared using serum samples from clinically healthy animals (n=33) and horses with neurological signs (n=21). High Spearman rank correlations (0.76-0.86) were found among the ELISA results. Inter-test agreements (weighted kappa) for assay interpretation resulted in strong agreement (0.95) of the results obtained by the mAbs and moderate agreements when monoclonal and polyclonal anti-IgM-based assays were compared. To determine the analytical sensitivities of anti-WNV IgM detection, serial dilutions of WNV IgM-positive serum samples were analyzed. The highest sensitivity was obtained by using the anti-IgM 1-22 mAb to capture IgM from equine serum. In conclusion, the use of monoclonal anti-IgM antibodies can improve the sensitivity of IgM detection in the acute phase of WN disease.

  11. Inhibition of equine arteritis virus by an antimicrobial peptide produced by Bacillus sp. P34

    Directory of Open Access Journals (Sweden)

    D. Scopel e Silva

    Full Text Available ABSTRACT P34 is an antimicrobial peptide produced by Bacillus sp. P34, isolated from the intestinal contents of a fish from the Amazon basin. This peptide showed antibacterial properties against Gram-positive and Gram-negative bacteria and was characterized as a bacteriocin like substance. It was demonstrated that the peptide P34 exhibited antiviral activity against feline herpesvirus type 1 in vitro. The aim of this work was to evaluate P34 for its antiviral properties in vitro, using RK 13 cells, against the equine arteritis virus, since it has no specific treatment and a variable proportion of stallions may become persistently infected. The results obtained show that P34 exerts antiviral and virucidal activities against equine arteritis virus, probably in the viral envelope. The antiviral assays performed showed that P34 reduces significantly the viral titers of treated cell cultures. The mechanism of action of P34 seems to be time/temperature-dependent. This peptide tends to be a promising antiviral compound for the prevention and treatment of arteriviral infections since it has a high therapeutic index. However, more detailed studies must be performed to address the exact step of viral infection where P34 acts, in order to use this peptide as an antiviral drug in vivo in the future.

  12. Comparison of genotypes I and III in Japanese encephalitis virus reveals distinct differences in their genetic and host diversity.

    Science.gov (United States)

    Han, Na; Adams, James; Chen, Ping; Guo, Zhen-yang; Zhong, Xiang-fu; Fang, Wei; Li, Na; Wen, Lei; Tao, Xiao-yan; Yuan, Zhi-ming; Rayner, Simon

    2014-10-01

    Japanese encephalitis (JE) is an arthropod-borne disease associated with the majority of viral encephalitis cases in the Asia-Pacific region. The causative agent, Japanese encephalitis virus (JEV), has been phylogenetically divided into five genotypes. Recent surveillance data indicate that genotype I (GI) is gradually replacing genotype III (GIII) as the dominant genotype. To investigate the mechanism behind the genotype shift and the potential consequences in terms of vaccine efficacy, human cases, and virus dissemination, we collected (i) all full-length and partial JEV molecular sequences and (ii) associated genotype and host information comprising a data set of 873 sequences. We then examined differences between the two genotypes at the genetic and epidemiological level by investigating amino acid mutations, positive selection, and host range. We found that although GI is dominant, it has fewer sites predicted to be under positive selection, a narrower host range, and significantly fewer human isolates. For the E protein, the sites under positive selection define a haplotype set for each genotype that shows striking differences in their composition and diversity, with GIII showing significantly more variety than GI. Our results suggest that GI has displaced GIII by achieving a replication cycle that is more efficient but is also more restricted in its host range. Japanese encephalitis is an arthropod-borne disease associated with the majority of viral encephalitis cases in the Asia-Pacific region. The causative agent, Japanese encephalitis virus (JEV), has been divided into five genotypes based on sequence similarity. Recent data indicate that genotype I (GI) is gradually replacing genotype III (GIII) as the dominant genotype. Understanding the reasons behind this shift and the potential consequences in terms of vaccine efficacy, human cases, and virus dissemination is important for controlling the spread of the virus and reducing human fatalities. We

  13. Mechanisms of equine infectious anemia virus escape from neutralizing antibody responses define epitope specificity.

    Science.gov (United States)

    Sponseller, Brett A; Clark, Sandra K; Friedrich, Rachel A

    2012-08-01

    Determining mechanisms of viral escape to particular epitopes recognized by virus-neutralizing antibody can facilitate characterization of host-neutralizing antibody responses as type- versus group-specific, and provides necessary information for vaccine development. Our study reveals that a single N-glycan located in the 5' region of the Wyoming wild-type equine infectious anemia virus (EIAV) principal neutralizing domain (PND) accounts for the differences in neutralization phenotype observed between PND variants, while variations in charged amino acids within the PND do not appear to play a key role in viral escape. Site-directed mutagenesis and peptide mapping of a conserved epitope to neutralizing antibody in the 3' region of the PND showed rapid selective pressure for acquisition of a 5' PND N-glycan responsible for defining the specificity of the neutralizing-antibody response.

  14. Detection of eastern equine encephalomyelitis virus RNA in North American snakes.

    Science.gov (United States)

    Bingham, Andrea M; Graham, Sean P; Burkett-Cadena, Nathan D; White, Gregory S; Hassan, Hassan K; Unnasch, Thomas R

    2012-12-01

    The role of non-avian vertebrates in the ecology of eastern equine encephalomyelitis virus (EEEV) is unresolved, but mounting evidence supports a potential role for snakes in the EEEV transmission cycle, especially as over-wintering hosts. To determine rates of exposure and infection, we examined serum samples from wild snakes at a focus of EEEV in Alabama for viral RNA using quantitative reverse transcription polymerase chain reaction. Two species of vipers, the copperhead (Agkistrodon contortrix) and the cottonmouth (Agkistrodon piscivorus), were found to be positive for EEEV RNA using this assay. Prevalence of EEEV RNA was more frequent in seropositive snakes than seronegative snakes. Positivity for the quantitative reverse transcription polymerase chain reaction in cottonmouths peaked in April and September. Body size and sex ratios were not significantly different between infected and uninfected snakes. These results support the hypothesis that snakes are involved in the ecology of EEEV in North America, possibly as over-wintering hosts for the virus.

  15. Canine distemper virus-associated encephalitis in free-living lynx (Lynx canadensis) and bobcats (Lynx rufus) of eastern Canada.

    Science.gov (United States)

    Daoust, Pierre-Yves; McBurney, Scott R; Godson, Dale L; van de Bildt, Marco W G; Osterhaus, Albert D M E

    2009-07-01

    Between 1993 and 1999, encephalitis caused by morbillivirus was diagnosed by immunohistochemistry and histology in six lynx (Lynx canadensis) and one bobcat (Lynx rufus) in the eastern Canadian provinces of New Brunswick and Nova Scotia. Five of the six cases in lynx occurred within an 11-mo period in 1996-97. A second bobcat with encephalitis caused by unidentified protozoa and a nematode larva also had immunohistochemical evidence of neurologic infection by morbillivirus. The virus was identified as canine distemper virus (CDV) by reverse transcriptase polymerase chain reaction and nucleotide sequencing in four of five animals from which frozen tissue samples were available, and it was isolated in cell culture from one of them. To our knowledge, this is the first report of disease caused by CDV in free-living felids in North America.

  16. Lymphocyte-Dominant Encephalitis and Meningitis in Simian Immunodeficiency Virus-Infected Macaques Receiving Antiretroviral Therapy.

    Science.gov (United States)

    Mangus, Lisa M; Beck, Sarah E; Queen, Suzanne E; Brill, Samuel A; Shirk, Erin N; Metcalf Pate, Kelly A; Muth, Dillon C; Adams, Robert J; Gama, Lucio; Clements, Janice E; Mankowski, Joseph L

    2018-01-01

    A retrospective neuropathologic review of 30 SIV-infected pigtailed macaques receiving combination antiretroviral therapy (cART) was conducted. Seventeen animals with lymphocyte-dominant inflammation in the brain and/or meninges that clearly was morphologically distinct from prototypic SIV encephalitis and human immunodeficiency virus encephalitis were identified. Central nervous system (CNS) infiltrates in cART-treated macaques primarily comprised CD20+ B cells and CD3+ T cells with fewer CD68+ macrophages. Inflammation was associated with low levels of SIV RNA in the brain as shown by in situ hybridization, and generally was observed in animals with episodes of cerebrospinal fluid (CSF) viral rebound or sustained plasma and CSF viremia during treatment. Although the lymphocytic CNS inflammation in these macaques shared morphologic characteristics with uncommon immune-mediated neurologic disorders reported in treated HIV patients, including CNS immune reconstitution inflammatory syndrome and neurosymptomatic CSF escape, the high prevalence of CNS lesions in macaques suggests that persistent adaptive immune responses in the CNS also may develop in neuroasymptomatic or mildly impaired HIV patients yet remain unrecognized given the lack of access to CNS tissue for histopathologic evaluation. Continued investigation into the mechanisms and outcomes of CNS inflammation in cART-treated, SIV-infected macaques will advance our understanding of the consequences of residual CNS HIV replication in patients on cART, including the possible contribution of adaptive immune responses to HIV-associated neurocognitive disorders. Copyright © 2018 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  17. Comparison of Four Serological Tests for Detecting Antibodies to Japanese Encephalitis Virus after Vaccination in Children

    Science.gov (United States)

    Cha, Go Woon; Cho, Jung Eun; Ju, Young Ran; Hong, Young-Jin; Han, Myung Guk; Lee, Won-Ja; Choi, Eui Yul; Jeong, Young Eui

    2014-01-01

    Objectives Several different methods are currently used to detect antibodies to Japanese encephalitis virus (JEV) in serum samples or cerebrospinal fluid. These methods include the plaque reduction neutralization test (PRNT), the hemagglutination inhibition (HI) test, indirect immunofluorescence assay (IFA), and enzyme-linked immunosorbent assay (ELISA). The purpose of this study was to compare the performance of each method in detecting vaccine-induced antibodies to JEV. Methods The study included 29 children who had completed a primary immunization schedule with an inactivated vaccine against JEV derived from mouse brain (n = 15) or a live attenuated SA14-14-2 vaccine (n = 14). Serum samples were collected between 3 months and 47 months after the last immunization. The serum samples were tested by performing the PRNT, HI test, in-house IFA, and commercial ELISA. The antibody detection rates were compared between tests. Results All 29 serum samples were positive with the PRNT, showing antibody titers from 1:20 to 1:2560. The HI test showed positive rates of 86.7% (13/15) and 71.4% (10/14) in the inactivated and live attenuated vaccine groups, respectively. The results of the IFA for immunoglobulin (Ig)G were positive in 53.3% (8/15) of children in the inactivated vaccine group and 35.7% (5/14) in the live attenuated vaccine group. Neither the IFA nor ELISA detected JEV IgM antibodies in any of the 29 children. Conclusion These results show that detection rates of vaccine-induced antibodies to JEV have a wide range (0–100%) depending on the testing method as well as the time since immunization and individual differences between children. These findings are helpful in interpreting serological test results for the diagnosis of Japanese encephalitis in situations where vaccines are widely administered. PMID:25389515

  18. Susceptibility of naïve and differentiated PC12 cells to Japanese encephalitis virus infection.

    Science.gov (United States)

    Li, Jian-Ri; Wu, Chih-Cheng; Chang, Cheng-Yi; Ou, Yen-Chuan; Lin, Shih-Yi; Wang, Ya-Yu; Chen, Wen-Ying; Raung, Shue-Ling; Liao, Su-Lan; Chen, Chun-Jung

    2017-02-01

    Japanese encephalitis is a mosquito-borne disease caused by Japanese encephalitis virus (JEV) infection. Although JEV infects and replicates in cells with multiple tissue origins, neurons are the preferential cells for JEV infection. Currently, the identities of JEV cell tropism are largely unclear. To gain better insight into the underlying identities of JEV cell tropism, this study was designed to compare the JEV cell tropism with naïve or differentiated PC12 cells. Through nerve growth factor-differentiated PC12 cells, we discovered that JEV efficiently replicated in differentiated PC12 cells rather than naïve cells. Mechanistic studies revealed that viral adsorption/attachment seemed not to be a crucial factor. Supporting data showed that antagonizing postreceptor intracellular signaling of interferons, along with the activation of suppressor of cytokine signaling-3 (SOCS3) expression and protein tyrosine phosphatase activity, were apparent in differentiated PC12 cells after JEV infection. Independent of differentiating inducing agents, the upregulation of SOCS3 expression and protein tyrosine phosphatase activity, as well as preferential JEV tropism, were common in JEV-infected differentiated PC12 cells. Using cultured primary neurons, JEV efficiently replicated in embryonic neurons rather than adult neurons, and the preference was accompanied by higher SOCS3 expression and protein tyrosine phosphatase activity. Given that both SOCS3 and protein tyrosine phosphatases have been implicated in the process of neuronal differentiation, JEV infection seems to not only create an antagonizing strategy to escape host's interferon antiviral response but also takes advantage of cellular machinery to favor its replication. Taken together, current findings imply that dynamic changes within cellular regulators of antiviral machinery could be accompanied by events of neuronal differentiation, thus concurrently playing roles in the control of JEV cell tropism and

  19. SAINT LOUIS ENCEPHALITIS VIRUS IN MATO GROSSO, CENTRAL-WESTERN BRAZIL

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    Letícia Borges da Silva HEINEN

    2015-06-01

    Full Text Available The dengue virus (DENV, which is frequently involved in large epidemics, and the yellow fever virus (YFV, which is responsible for sporadic sylvatic outbreaks, are considered the most important flaviviruses circulating in Brazil. Because of that, laboratorial diagnosis of acute undifferentiated febrile illness during epidemic periods is frequently directed towards these viruses, which may eventually hinder the detection of other circulating flaviviruses, including the Saint Louis encephalitis virus (SLEV, which is widely dispersed across the Americas. The aim of this study was to conduct a molecular investigation of 11 flaviviruses using 604 serum samples obtained from patients during a large dengue fever outbreak in the state of Mato Grosso (MT between 2011 and 2012. Simultaneously, 3,433 female Culex spp. collected with Nasci aspirators in the city of Cuiabá, MT, in 2013, and allocated to 409 pools containing 1-10 mosquitoes, were also tested by multiplex semi-nested reverse transcription PCR for the same flaviviruses. SLEV was detected in three patients co-infected with DENV-4 from the cities of Cuiabá and Várzea Grande. One of them was a triple co-infection with DENV-1. None of them mentioned recent travel or access to sylvatic/rural regions, indicating that transmission might have occurred within the metropolitan area. Regarding mosquito samples, one pool containing one Culex quinquefasciatus female was positive for SLEV, with a minimum infection rate (MIR of 0.29 per 1000 specimens of this species. Phylogenetic analysis indicates both human and mosquito SLEV cluster, with isolates from genotype V-A obtained from animals in the Amazon region, in the state of Pará. This is the first report of SLEV molecular identification in MT.

  20. Achievements of an eradication program against caprine arthritis encephalitis virus in South Tyrol, Italy.

    Science.gov (United States)

    Tavella, Alexander; Bettini, Astrid; Ceol, Marco; Zambotto, Paolo; Stifter, Ernst; Kusstatscher, Natashia; Lombardi, Rosalba; Nardeli, Stefano; Beato, Maria Serena; Capello, Katia; Bertoni, Giuseppe

    2017-11-06

    Small ruminant lentivirus infections in goats affect both production and animal welfare. This represents a threat to the qualitative and quantitative growth of goat farming, recently observed in mountainous regions such as the Autonomous Province of Bolzano - South Tyrol (Italy). To monitor and eradicate the caprine arthritis encephalitis virus in this goat population, a compulsory eradication campaign was launched, based on a strict census of small ruminants and yearly serological testing of all animals, followed by the consequent culling of seropositive individuals. The campaign succeeded in completely eliminating cases of clinical disease in goats, while drastically reducing the seroprevalence at the herd as well as individual animal level. The serological outcome of the introduced control measures was determined using commercially available ELISA kits, demonstrating their suitability for use in this type of campaign, aimed at reducing seroprevalence as well as clinical manifestations of these infections. However, this clear success is diminished by the failure to achieve a complete eradication of these viruses. The reasons leading to the observed tailing phenomenon and the occurrence of new infections in already sanitised flocks are discussed and implementation of further measures are proposed. © British Veterinary Association (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  1. Tick-borne encephalitis virus in dogs - is this an issue?

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    Dobler Gerhard

    2011-04-01

    Full Text Available Abstract The last review on Tick-borne encephalitis (TBE in dogs was published almost ten years ago. Since then, this zoonotic tick-borne arbovirus has been geographically spreading and emerging in many regions in Eurasia and continues to do so. Dogs become readily infected with TBE virus but they are accidental hosts not capable to further spread the virus. They seroconvert upon infection but they seem to be much more resistant to the clinical disease than humans. Apart from their use as sentinels in endemic areas, however, an increasing number of case reports appeared during the last decade thus mirroring the rising public health concerns. Owing to the increased mobility of people travelling to endemic areas with their companion dogs, this consequently leads to problems in recognizing and diagnosing this severe infection in a yet non-endemic area, simply because the veterinarians are not considering TBE. This situation warrants an update on the epidemiology, clinical presentation and possible preventions of TBE in the dog.

  2. Epidemiological Study of Japanese Encephalitis Virus in Vientiane, Lao PDR, in 1990s

    Science.gov (United States)

    Saito, Mika; Soukaloun, Douangdao; Phongsavath, Khampe; Phommasack, Bounlay; Makino, Yoshihiro

    2015-01-01

    Phylogenetic analysis of Japanese encephalitis virus (JEV) was conducted using core-premembrane and envelope gene sequence data of two strains from Vientiane, Lao People's Democratic Republic, in 1993 and five from Okinawa, Japan, in 2002 and 2003, and previously published strains. The two Vientiane strains designated as LaVS56 and LaVS145 belonged to genotype 1 (G1) and the same subcluster of G1 as Australian strain in 2000, Thai strains in 1982–1985 and 2004-2005, and Vietnamese strain in 2005, but were distinct from the subcluster of recently distributing G1 strains widely in Asia including Okinawan strains and recent Lao strain in 2009. These clusters with own distinct distributions indicated involvements of different mechanisms and routes of spreading viruses and clarified that Australian G1 strain is from Southeast Asia, not from East Asia. Both Vientiane strains were antigenically close to P19-Br (G1, isolate, Thailand), but distinct from Nakayama (G3, prototype strain, Japan), Beijing-1 (G3, laboratory strain, China), and JaGAr#01 (G3, laboratory strain, Japan), demonstrated by cross-neutralization tests using polyclonal antisera. These results together with seroepidemiologic study conducted in Vientiane strongly suggest that diversified JEV cocirculated there in early 1990s. PMID:25695095

  3. [Characteristics of the ecology of the eastern equine encephalomyelitis virus in the Republic of Cuba].

    Science.gov (United States)

    Berezin, V V

    1977-01-01

    Virologic and serological surveys of wild vertebrates carried out in various provinces of Cuba demonstrated definitely that birds were the main hosts of eastern equine encephalomyelitis (EEE) virus in this territory. Fifteen strains of this virus were isolated from 8 species of birds belonging to 5 orders. Isolation of EEE virus from the blood of the endemic genus of iguanas indicates a certain role of cold-blooded animals in the ecology of this agent. Active EEE virus foci have been found in 4 provinces of the Republic of Cuba: Pinar del Rio, Havana, Matanzas and Las Villas. Isolation of a number of EEE virus strains from sick horses during an epizootic in the latter province confirmed the importance role of this agent in the infectious pathology of domestic animals in Cuba. The experimental results suggest that in Cuba there occur at least two types of foci of this infection: forest and water-littoral (fresh-water swamps and lakes, and sea coast with mangrove forests).

  4. Seroprevalence and risk factor analysis for exposure to equine encephalosis virus in Israel, Palestine and Jordan.

    Science.gov (United States)

    Tirosh-Levy, Sharon; Gelman, Boris; Zivotofsky, Doni; Quraan, Lara; Khinich, Evgeny; Nasereddin, Abdelmajeed; Abdeen, Ziad; Steinman, Amir

    2017-05-01

    Equine encephalosis virus (EEV) is an orbivirus transmitted by Culicoides species. Most infected horses show mild clinical signs and mortality is usually very low. EEV is closely related and similarly transmitted to other, more pathogenic and economically important, orbiviruses such as African horse sickness virus (AHSV), bluetongue virus (BTV) and epizootic haemorrhagic disease viruses (EHDV), and may serve as an indicator for possible transmission of the latter. Israel has been reported to be endemic for EEV since 2001. This study was initiated to re-evaluate the current seroprevalence and risk factors for EEV exposure in Israel, and to assess, for the first time, the seroprevalence of EEV in Palestine and Jordan. Three hundred and sixteen serum samples were collected from apparently healthy horses at 21 farms in Israel, 66 horses at nine farms in Palestine and 100 horses at three farms in Jordan. The presence of EEV antibodies was detected by a serum neutralization assay. Seroprevalence of EEV was 58.2% (184/316 horses) in Israel, 48.5% (32/66 horses) in Palestine and 2% (2/100 horses) in Jordan. Seroprevalence in Jordan was significantly lower than in Israel and Palestine (P Palestine and horses in Jordan were also exposed to this virus emphasizing the potential of pathogens to invade new ecological niches.

  5. Landscape features and reservoir occurrence affecting the risk for equine infection with Borna disease virus.

    Science.gov (United States)

    Encarnação, Jorge A; Herzog, Sibylle; Eickmann, Markus; Becker, Nina I; Hermes, Nicole; Herden, Christiane

    2013-10-01

    Borna disease (BD) is a severe endemic and fatal disorder caused by the neurotropic Borna disease virus (BDV) which mainly occurs in horses and sheep. Borna disease virus belongs to the order Mononegavirales, which includes many reservoir-bound viruses with high zoonotic and pathogenic properties including the filoviruses and lyssaviruses. Clinically manifest BD occurs in endemic areas of Germany, Switzerland, Liechtenstein, and Austria. A seasonal accumulation of cases in spring and summer, incidences that vary from year to year, and the recent detection of BDV in bicolored shrews (Crocidura leucodon) in Swiss endemic areas argue for a natural reservoir. We established a geographic information system analysis of the distribution of 485 equine BD cases in Bavarian (Germany) endemic areas and of the occurrence of 285 records of C. leucodon captured in Bavaria. Boosted regression trees were used to identify driving factors of habitat choice and virus prevalence. The distribution model of C. leucodon and the prevalence model for BDV had very good accuracy. Mean annual precipitation 500 m. Our results indicate that the distribution model can accurately predict BD occurrence. Based on these results, practical safety precautions could be derived. The BDV model represents a suitable system for reservoir-bound, neurotropic Mononegavirales because it allows analyzing ecologic and biologic aspects that determine virus abundance, maintenance in reservoir species, and transmission to end host species.

  6. Experimental Transmission of Venezuelan Equine Encephalomyelitis Virus by a Strain of Aedes albopictus (Diptera: Culicidae) from New Orleans, Louisiana

    Science.gov (United States)

    1992-09-01

    2). However, the strains of Aedes albopictus (Diptera: Culicidae) col- greater susceptibility of the Brazilian strains than lected in North and South...AD-A259 565 Experimental Transmission of Venezuelan Equine Encephalomyelitis Virus by a Strain of Aedes albopictus (Diptera: Culicidae) S1 ls from... susceptibility of’ selected strains of’ Ecuador and Peru in northern South America Ac. albopictus for VEE and CHIK viruses to de- and as far north as southern

  7. Cryptic etiopathological conditions of equine nervous system with special emphasis on viral diseases

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    Rakesh Kumar

    2017-12-01

    Full Text Available The importance of horse (Equus caballus to equine practitioners and researchers cannot be ignored. An unevenly distributed population of equids harbors numerous diseases, which can affect horses of any age and breed. Among these, the affections of nervous system are potent reason for death and euthanasia in equids. Many episodes associated with the emergence of equine encephalitic conditions have also pose a threat to human population as well, which signifies their pathogenic zoonotic potential. Intensification of most of the arboviruses is associated with sophisticated interaction between vectors and hosts, which supports their transmission. The alphaviruses, bunyaviruses, and flaviviruses are the major implicated groups of viruses involved with equines/humans epizootic/epidemic. In recent years, many outbreaks of deadly zoonotic diseases such as Nipah virus, Hendra virus, and Japanese encephalitis in many parts of the globe addresses their alarming significance. The equine encephalitic viruses differ in their global distribution, transmission and main vector species involved, as discussed in this article. The current review summarizes the status, pathogenesis, pathology, and impact of equine neuro-invasive conditions of viral origin. A greater understanding of these aspects might be able to provide development of advances in neuro-protective strategies in equine population.

  8. Seroprevalence of antibodies to Venezuelan equine encephalitis complex (subtypes IAB and VI in humans from General Belgrano Island, Formosa, Argentina

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    Cámara Alicia

    2003-01-01

    Full Text Available This work presents the results of the detection of antibodies (immunoglobulin G for subtypes I and VI of VEE viruses complex (Togaviridae family in people from the General Belgrano island, Formosa province (Argentina. The prevalence of neutralizing (NT antibodies for subtype VI was from 30% to 70% and the prevalence of antibodies inhibitory of hemagglutination (HI was of 0% in the first and second inquiry respectively. For the subtype IAB the prevalence of NT antibodies was from 13% to 3.6%, similar to the prevalence total for both subtypes. HI antibodies were not detected in any inquiries for any subtype. It was observed that both subtypes circulate simultaneously, while subtype VI remains constant with some peaks, subtype I was found in low level.

  9. Anti-equine arteritis virus activity of ethanolic extract and compounds from Origanum vulgare

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    Daiane Einhardt Blank

    2017-05-01

    Full Text Available The equine arteritis virus (EAV is responsible by an important respiratory and reproductive disease in equine populations and there is no specific antiviral treatment available. The objective of this study was to investigate the activity of an ethanolic crude extract of Origanum vulgare (EEO and of isolated compound caffeic acid, p-coumaric acid, rosmarinic acid, quercetin, luteolin, carnosol, carnosic acid, kaempferol and apigenin against EAV. The assays were performed using non-cytotoxic concentrations. The antiviral activity was monitored initially by cytopathic effect inhibition (CPE assay in RK13 cells in the presence or absence of EEO. Pre-incubated cells with EEO were also examined to show prophylactic effect. Direct viral inactivation by EEO and isolated compounds was evaluated by incubation at 37°C or 20°C. After the incubation period, the infectivity was immediately determined by virus titrations on cell cultures and expressed as 50% tissue culture infective dose (TCID50/100 µL. There was significant virucidal activity of EEO and of the compounds caffeic acid, p-coumaric acid, quercetin, carnosic acid and kaempferol. When EEO was added after infection, EEO inhibited the virus growth in infected cells, as evidenced by significant reduction of the viral titre. The results provide evidence that the EEO exhibit an inhibitory effect anti-EAV. Among the main compounds evaluated, caffeic acid, p-coumaric acid, carnosic acid, kaempferol and mainly quercetin, contributed to the activity of EEO. EEO may represent a good prototype for the development of a new antiviral agent, presenting promising for combating arteriviruses infections.

  10. MicroRNA transcriptome profiling of mice brains infected with Japanese encephalitis virus by RNA sequencing.

    Science.gov (United States)

    Li, Xin-Feng; Cao, Rui-Bing; Luo, Jun; Fan, Jian-Ming; Wang, Jing-Man; Zhang, Yuan-Peng; Gu, Jin-Yan; Feng, Xiu-Li; Zhou, Bin; Chen, Pu-Yan

    2016-04-01

    Japanese encephalitis (JE) is a mosquito borne viral disease, caused by Japanese encephalitis virus (JEV) infection producing severe neuroinflammation in the central nervous system (CNS) with the associated disruption of the blood brain barrier. MicroRNAs (miRNAs) are a family of 21-24 nt small non-coding RNAs that play important post-transcriptional regulatory roles in gene expression and have critical roles in virus pathogenesis. We examined the potential roles of miRNAs in JEV-infected suckling mice brains and found that JEV infection changed miRNA expression profiles when the suckling mice began showing nervous symptoms. A total of 1062 known and 71 novel miRNAs were detected in JEV-infected group, accompanied with 1088 known and 75 novel miRNAs in mock controls. Among these miRNAs, one novel and 25 known miRNAs were significantly differentially expressed, including 18 up-regulated and 8 down-regulated miRNAs which were further confirmed by real-time PCR. Gene ontology (GO) and signaling pathway analysis of the predicted target mRNAs of the modulated miRNAs showed that they are correlated with the regulation of apoptosis, neuron differentiation, antiviral immunity and infiltration of mouse brain, and the validated targets of 12 differentially expressed miRNAs were enriched for the regulation of cell programmed death, proliferation, transcription, muscle organ development, erythrocyte differentiation, gene expression, plasma membrane and protein domain specific binding. KEGG analysis further reveals that the validated target genes were involved in the Pathways in cancer, Neurotrophin signaling pathway, Toll like receptor signaling pathway, Endometrial cancer and Jak-STAT signaling pathway. We constructed the interaction networks of miRNAs and their target genes according to GO terms and KEGG pathways and the expression levels of several target genes were examined. Our data provides a valuable basis for further studies on the regulatory roles of miRNAs in JE

  11. Differential Infectivities among Different Japanese Encephalitis Virus Genotypes in Culex quinquefasciatus Mosquitoes.

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    Yan-Jang S Huang

    2016-10-01

    Full Text Available During the last 20 years, the epidemiology of Japanese encephalitis virus (JEV has changed significantly in its endemic regions due to the gradual displacement of the previously dominant genotype III (GIII with clade b of GI (GI-b. Whilst there is only limited genetic difference distinguishing the two GI clades (GI-a and GI-b, GI-b has shown a significantly wider and more rapid dispersal pattern in several regions in Asia than the GI-a clade, which remains restricted in its geographic distribution since its emergence. Although previously published molecular epidemiological evidence has shown distinct phylodynamic patterns, characterization of the two GI clades has only been limited to in vitro studies. In this study, Culex quinquefasciatus, a known competent JEV mosquito vector species, was orally challenged with three JEV strains each representing GI-a, GI-b, and GIII, respectively. Infection and dissemination were determined based on the detection of infectious viruses in homogenized mosquitoes. Detection of JEV RNA in mosquito saliva at 14 days post infection indicated that Cx. quinquefasciatus can be a competent vector species for both GI and GIII strains. Significantly higher infection rates in mosquitoes exposed to the GI-b and GIII strains than the GI-a strain suggest infectivity in arthropod vectors may lead to the selective advantage of previously and currently dominant genotypes. It could thus play a role in enzootic transmission cycles for the maintenance of JEV if this virus were ever to be introduced into North America.

  12. Interstitial lung disease associated with Equine Infectious Anemia Virus infection in horses.

    Science.gov (United States)

    Bolfa, Pompei; Nolf, Marie; Cadoré, Jean-Luc; Catoi, Cornel; Archer, Fabienne; Dolmazon, Christine; Mornex, Jean-François; Leroux, Caroline

    2013-12-01

    EIA (Equine Infectious Anemia) is a blood-borne disease primarily transmitted by haematophagous insects or needle punctures. Other routes of transmission have been poorly explored. We evaluated the potential of EIAV (Equine Infectious Anemia Virus) to induce pulmonary lesions in naturally infected equids. Lungs from 77 EIAV seropositive horses have been collected in Romania and France. Three types of lesions have been scored on paraffin-embedded lungs: lymphocyte infiltration, bronchiolar inflammation, and thickness of the alveolar septa. Expression of the p26 EIAV capsid (CA) protein has been evaluated by immunostaining. Compared to EIAV-negative horses, 52% of the EIAV-positive horses displayed a mild inflammation around the bronchioles, 22% had a moderate inflammation with inflammatory cells inside the wall and epithelial bronchiolar hyperplasia and 6.5% had a moderate to severe inflammation, with destruction of the bronchiolar epithelium and accumulation of smooth muscle cells within the pulmonary parenchyma. Changes in the thickness of the alveolar septa were also present. Expression of EIAV capsid has been evidenced in macrophages, endothelial as well as in alveolar and bronchiolar epithelial cells, as determined by their morphology and localization. To summarize, we found lesions of interstitial lung disease similar to that observed during other lentiviral infections such as FIV in cats, SRLV in sheep and goats or HIV in children. The presence of EIAV capsid in lung epithelial cells suggests that EIAV might be responsible for the broncho-interstitial damages observed.

  13. Development and evaluation of aerosol delivery of antivirals for the treatment of equine virus induced respiratory infections

    Energy Technology Data Exchange (ETDEWEB)

    Martens, J.G.

    1985-01-01

    An aerosol delivery system incorporating the DeVilbiss ultrasonic nebulizer was developed for antiviral chemotherapy of equine viral respiratory infections. The system's delivery capabilities were proven effective by two modes of analysis: (a) a non-destructive, non-invasive radioactive tracer method utilizing a saline solution of DTPA labelled 99mTc and, (b) an invasive-terminal study using fluorescent polystyrene monodispersed latex particles. Particles were efficiently distributed throughout the lung parenchyma with deposition more heavily concentrated in the tracheobronchial region. Amantadine HCl was administered to the lungs of a yearling horse and three yearling Shetland ponies over a single 15-30 minute period with no untoward side effects. Likewise, ribavirin was aerosolized into the respiratory trace of an adult pony and a yearling horse for 15-30 minutes twice a day for three and seven days respectively. Neither the horse nor pony demonstrated signs of clinical illness or other signs of ribavirin toxicity. Attempts to produce a reproducible equine influenza disease model were made. During these studies, the authors were unsuccessful in developing a consistent respiratory disease model. Without this model the efficacy of antiviral compounds cannot be assessed. From the data generated in these studies, the implication of equine influenza viruses as the major single etiological agents responsible for equine respiratory disease is brought into question. Further, the author proposed that equine respiratory disease is a multiple agent-induced disease, which needs extensive investigation.

  14. Interim Report on SNP analysis and forensic microarray probe design for South American hemorrhagic fever viruses, tick-borne encephalitis virus, henipaviruses, Old World Arenaviruses, filoviruses, Crimean-Congo hemorrhagic fever viruses, Rift Valley fever

    Energy Technology Data Exchange (ETDEWEB)

    Jaing, C; Gardner, S

    2012-06-05

    The goal of this project is to develop forensic genotyping assays for select agent viruses, enhancing the current capabilities for the viral bioforensics and law enforcement community. We used a multipronged approach combining bioinformatics analysis, PCR-enriched samples, microarrays and TaqMan assays to develop high resolution and cost effective genotyping methods for strain level forensic discrimination of viruses. We have leveraged substantial experience and efficiency gained through year 1 on software development, SNP discovery, TaqMan signature design and phylogenetic signature mapping to scale up the development of forensics signatures in year 2. In this report, we have summarized the whole genome wide SNP analysis and microarray probe design for forensics characterization of South American hemorrhagic fever viruses, tick-borne encephalitis viruses and henipaviruses, Old World Arenaviruses, filoviruses, Crimean-Congo hemorrhagic fever virus, Rift Valley fever virus and Japanese encephalitis virus.

  15. Human pegivirus detected in a patient with severe encephalitis using a metagenomic pan-virus array

    DEFF Research Database (Denmark)

    Fridholm, Helena; Østergaard Sørensen, Line; Rosenstierne, Maiken W.

    2016-01-01

    We have used a metagenomic microarray to detect genomic RNA from human pegivirus in serum and cerebrospinal fluid from a patient suffering from severe encephalitis. No other pathogen was detected. HPgV in cerebrospinal fluid during encephalitis has never been reported before and its prevalence...

  16. Oxidant-antioxidant imbalance in horses infected with equine infectious anaemia virus.

    Science.gov (United States)

    Bolfă, Pompei Florin; Leroux, Caroline; Pintea, Adela; Andrei, Sanda; Cătoi, Cornel; Taulescu, Marian; Tăbăran, Flaviu; Spînu, Marina

    2012-06-01

    This study assesses the impact of equine infectious anaemia virus (EIAV) infection on the oxidant/antioxidant equilibrium of horses. Blood samples from 96 Romanian horses aged 1-25 years, were divided into different groups according to their EIAV-infection status, age, and time post-seroconversion. The effect of infection on oxidative stress was estimated by measuring enzymatic antioxidants (superoxide dismutase [SOD], glutathione peroxidase [GPx] and catalase), non-enzymatic antioxidants (uric acid and carotenoids), and lipid peroxidation (malondialdehyde [MDA]). Infection modified the oxidant/antioxidant equilibrium in the horses, influencing GPx and uric acid levels (P5 years old, represented the most vulnerable category in terms of oxidative stress, followed by recently infected animals <5 years old. The results of this study are novel in implicating EIAV infection in the development of oxidative stress in horses. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Complete genome sequence of mumps viruses isolated from patients with parotitis, pancreatitis and encephalitis in India.

    Science.gov (United States)

    Vaidya, Sunil R; Chowdhury, Deepika T; Jadhav, Santoshkumar M; Hamde, Venkat S

    2016-04-01

    Limited information is available regarding epidemiology of mumps in India. Mumps vaccine is not included in the Universal Immunization Program of India. The complete genome sequences of Indian mumps virus (MuV) isolates are not available, hence this study was performed. Five isolates from bilateral parotitis and pancreatitis patients from Maharashtra, a MuV isolate from unilateral parotitis patient from Tamil Nadu, and a MuV isolate from encephalitis patient from Uttar Pradesh were genotyped by the standard protocol of the World Health Organization and subsequently complete genomes were sequenced. Indian MuV genomes were compared with published MuV genomes, including reference genotypes and eight vaccine strains for the genetic differences. The SH gene analysis revealed that five MuV isolates belonged to genotype C and two belonged to genotype G strains. The percent nucleotide divergence (PND) was 1.1% amongst five MuV genotype C strains and 2.2% amongst two MuV genotype G strains. A comparison with widely used mumps Jeryl Lynn vaccine strain revealed that Indian mumps isolates had 54, 54, 53, 49, 49, 38, and 49 amino acid substitutions in Chennai-2012, Kushinagar-2013, Pune-2008, Osmanabad-2012a, Osmanabad-2012b, Pune-1986 and Pune-2012, respectively. This study reports the complete genome sequences of Indian MuV strains obtained in years 1986, 2008, 2012 and 2013 that may be useful for further studies in India and globally. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Heat shock protein 90β in the Vero cell membrane binds Japanese encephalitis virus.

    Science.gov (United States)

    Wang, Yuan; Li, Yan; Ding, Tianbing

    2017-08-01

    The pathogenesis of Japanese encephalitis virus (JEV) is complex and unclearly defined, and in particular, the effects of the JEV receptor (JEVR) on diverse susceptible cells are elusive. In contrast to previous studies investigating JEVR in rodent or mosquito cells, in this study, we used primate Vero cells instead. We noted that few novel proteins co‑immunoprecipitated with JEV, and discovered that one of these was heat shock protein 90β (HSP90β), which was probed by mass spectrometry with the highest score of 60.3 after questing the monkey and human protein databases. The specific HSP90β‑JEV binding was confirmed by western blot analysis under non‑reducing conditions, and this was significantly inhibited by an anti‑human HSP90β monoclonal antibody in a dose‑dependent manner, as shown by immunofluorescence assay and flow cytometry. In addition, the results of confocal laser scanning microscopic examination demonstrated that the HSP90β‑JEV binding occurred on the Vero cell surface. Finally, JEV progeny yields determined by plaque assay were also markedly decreased in siRNA‑treated Vero cells, particularly at 24 and 36 h post‑infection. Thus, our data indicate that HSP90β is a binding receptor for JEV in Vero cells.

  19. Managing aggression in global amnesia following herpes simplex virus encephalitis: The case of E.B.

    Science.gov (United States)

    Shannon, Tracy E; Griffin, Stefanie L

    2015-01-01

    This article describes an integrative approach to the case of EB, a 33 year old male who presented with agitation, delusional ideation and global amnesia after contracting herpes simplex virus encephalitis (HSVE) while in a state prison in 2004. Although several prior case studies have described outcome following acute onset of HSVE, this case presents a unique challenge for rehabilitation in several respects. First, EB's pre-morbid history is complicated; in contrast with prior HSVE case studies that have typically involved individuals with a relatively high level of pre-morbid functioning, EB presents with limited educational attainment and a prior history of several incarcerations for violent offenses. Post-injury, his presentation includes significant verbal aggression, threats of harm toward others, physical posturing and occasional physical aggression toward his caretakers. Third, EB presents with a fixed delusion that others are constantly taking advantage of him. These features are present in the context of global amnesia and relatively intact cognitive functioning in other domains. Following a brief review of prior HSVE case studies, this study reviews the outcomes of various pharmacological, cognitive, behavioural and integrative interventions designed for management of EB's aggression and agitation.

  20. Reproductive performance in sows in relation to Japanese Encephalitis Virus seropositivity in an endemic area.

    Science.gov (United States)

    Lindahl, Johanna; Boqvist, Sofia; Ståhl, Karl; Thu, Ho Thi Viet; Magnusson, Ulf

    2012-02-01

    Japanese Encephalitis Virus (JEV) is considered an important reproductive pathogen in pigs. Most studies of the reproductive impact of JEV have been conducted in areas where the disease occurs in seasonal epidemics. In this study, the associations between seropositivity for JEV, measured with an IgG ELISA, and the number of piglets born alive and stillborn were investigated in a tropical area endemic for JEV in Vietnam. Sixty percent of sows from four farms in the Mekong delta of Vietnam were seropositive to JEV and the Odds Ratio for a sow being infected was highest (6.4) in sows above 3.5 years (95% confidence interval 2.2-18.3). There was an association between increasing Optical Density (OD) values from the ELISA and the number of stillborn piglets in sows less than 1.5 years, but no effect of seropositivity could be shown when all sows were studied. OD values had an effect (p = 0.04) on the number of piglets born alive in the statistical analysis only when interacting with the effect of the breeds. An increase in mean OD value of the herd was correlated (p immunity in many gilts before their first pregnancy. This, in turn, may imply that JEV infection in pigs is of minor importance for the reproductive performance in endemic areas.

  1. Susceptibility of a North American Culex quinquefasciatus to Japanese Encephalitis Virus.

    Science.gov (United States)

    Huang, Yan-Jang S; Harbin, Julie N; Hettenbach, Susan M; Maki, Elin; Cohnstaedt, Lee W; Barrett, Alan D T; Higgs, Stephen; Vanlandingham, Dana L

    2015-11-01

    Japanese encephalitis virus (JEV) is a flavivirus that is transmitted by Culex (Cx.) tritaeniorhynchus in tropical and subtropical regions of Asia. The endemic transmission cycle involves domestic pigs and avian species that serve as amplification hosts; humans are incidental hosts that cannot develop a high-titer viremia sufficient for mosquito infection. Although vaccination can be an effective strategy for disease prevention and is used extensively in multiple Asian countries, unvaccinated immunologically naïve human populations can suffer from severe neurological sequelae. The potential introduction of JEV into North America would be a major threat to human and animal health. In this study, field-collected Cx. quinquefasciatus from Valdosta, Georgia, were tested for their susceptibility to JEV and their potential to develop a disseminated infection via per os infection. These results demonstrate that North American Cx. quinquefasciatus are susceptible to JEV infection and subsequent dissemination at 14 days post infection (d.p.i.). Detection of viral RNA in saliva from infected mosquitoes also indicates competent vectors for JEV can be found in North America.

  2. [Study on Spatial Dispersal and Migration Events of Japanese Encephalitis Virus].

    Science.gov (United States)

    Gao, Xiaoyan; Zhou, Haiwei; Liu, Hong; Fu, Shihong; Wang, Huanyu; Guo, Zhenyang; Li, Xiaolong; Liang, Guodong

    2015-05-01

    To explore the spatial distribution mechanism of Japanese encephalitis virus (JEV), PhyML v3.0 was used to build phylogenetic tree using JEV sequences in the dataset. PAUP v4.0 and Migrapyhla softz ware were then used to analyze the migration events. The results showed that a total of 95 migration events were observed during the dispersal of JEV throughout Asia. Further analysis revealed that Thailand, and several Chinese provinces (including Shandong, Shanghai, Sichuan and Yunnan), were the main migration sources of JEV. JEV spread from these migration sources as follows: from Thailand to Australia, Cambodia, Tibet and India; from Shanghai to eastern coastal Asian regions and Yunnan; from Shandong to Korea, Zhejiang, Hubei, Shanxi and Liaoning; from Sichuan mainly to inland regions of China, as well as Vietnam and Japan; and from Yunnan to Zhejiang. This study indicated that frequent migration events occurred during the dispersal of JEV in the Asia and Pacific regions, and that Thailand, Shandong, Shanghai, Sichuan and Yunnan were the sources of JEV dispersal.

  3. In vitro growth, pathogenicity and serological characteristics of the Japanese encephalitis virus genotype V Muar strain.

    Science.gov (United States)

    Tajima, Shigeru; Yagasaki, Kazumi; Kotaki, Akira; Tomikawa, Takumi; Nakayama, Eri; Moi, Meng Ling; Lim, Chang-Kweng; Saijo, Masayuki; Kurane, Ichiro; Takasaki, Tomohiko

    2015-09-01

    The characteristics of genotype V Japanese encephalitis virus (GV JEV) remain poorly understood as only two strains have been isolated to date. In this study, we examined the effects of the GV JEV Muar strain on in vitro growth and pathogenicity in mice; we also evaluated the efficacy of inactivated JEV vaccines against the Muar strain. Although growth of the Muar strain in mouse neuroblastoma N18 cells was clearly worse than that of the GIII Beijing-1 and GI Mie/41/2002 strains, neuroinvasiveness of the Muar strain was similar to that of the Beijing-1 strain and significantly higher than that of the Mie/41/2002 strain. The results of a plaque reduction neutralization test suggested that the neutralization ability of the JEV vaccines against the Muar strain was reduced compared with the GI and GIII strains. However, the protection potency of the JEV vaccine against the Muar strain was similar to that for the Beijing-1 strain in mice. Our data indicate that GV JEV has unique growth, virulence and antigenicity features.

  4. Experimental transmission of equine hepacivirus in horses as a model for hepatitis C virus.

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    Ramsay, Joshua D; Evanoff, Ryan; Wilkinson, Tom E; Divers, Thomas J; Knowles, Donald P; Mealey, Robert H

    2015-05-01

    Equine hepacivirus (EHCV; nonprimate hepacivirus) is a hepatotropic member of the Flaviviridae family that infects horses. Although EHCV is the closest known relative to hepatitis C virus (HCV), its complete replication kinetics in vivo have not been described, and direct evidence that it causes hepatitis has been lacking. In this study, we detected EHCV in 2 horses that developed post-transfusion hepatitis. Plasma and serum from these horses were used to experimentally transmit EHCV to 4 young adult Arabian horses, two 1-month-old foals (1 Arabian and 1 Arabian-pony cross), and 2 foals (1 Arabian and 1 Arabian-pony cross) with severe combined immunodeficiency (SCID). Our results demonstrated that EHCV had infection kinetics similar to HCV and that infection was associated with acute and chronic liver disease as measured by elevations of liver-specific enzymes and/or by histopathology. Although most of these animals were coinfected with equine pegivirus (EPgV), also a flavivirus, EPgV viral loads were much lower and often undetectable in both liver and blood. Three additional young adult Arabian-pony crosses and 1 SCID foal were then inoculated with plasma containing only EHCV, and evidence of mild hepatocellular damage was observed. The different levels of liver-specific enzyme elevation, hepatic inflammation, and duration of viremia observed during EHCV infection suggested that the magnitude and course of liver disease was mediated by the virus inoculum and/or by host factors, including breed, age, and adaptive immune status. This work documents the complete infection kinetics and liver pathology associated with acute and chronic EHCV infection in horses and further justifies it as a large animal model for HCV. © 2015 by the American Association for the Study of Liver Diseases.

  5. [L-Lysine-α-Oxidase in vitro Activity in Experiments on Models of Viruses Sindbis, Forest-Spring Encephalitis, Western Nile, Tyaginya and Dhori].

    Science.gov (United States)

    Smirnova, I P; Larichev, V F; Shneider, Yu A

    2015-01-01

    The antitumor effect of L-lysine-α-oxidase from the culture fluid of Trichoderma harzianum Rifai F-180 was investigated for the first time. The in vitro studies revealed its high activity on a model of the forest-spring encephalitis virus and no activity against the Sindbis, Western Nile, Tyaginya and Dhori viruses.

  6. Long-term follow-up of Japanese encephalitis chimeric virus vaccine: Immune responses in children.

    Science.gov (United States)

    Chokephaibulkit, Kulkanya; Sirivichayakul, Chukiat; Thisyakorn, Usa; Pancharoen, Chitsanu; Boaz, Mark; Bouckenooghe, Alain; Feroldi, Emmanuel

    2016-11-04

    A single dose of live attenuated Japanese encephalitis chimeric virus vaccine (JE-CV) was shown to be immunogenic and well tolerated when given either as a booster to formalin-inactivated Japanese encephalitis (JE)-vaccine (mouse brain-derived vaccine [MBDV])-primed 2-5-year-olds, or as a primary vaccination to JE-vaccine-naïve 12-24-month-old toddlers in Thailand. A 5-year follow-up assessment of immune response persistence over time was conducted. Four additional visits (at 2, 3, 4, and 5years) for immunologic assessments were added to the original 12-month open-label crossover study, in which 100 healthy children aged 2-5years with a history of two-dose primary vaccination with MBDV (according to the Thai Expanded Program for Immunization schedule), and 200 healthy JE-vaccine-naïve 12-24-month-old toddlers, were randomized 1:1 to receive JE-CV, containing ⩾4 log 10 plaque forming units, 1month before or after hepatitis A control vaccine. In MBDV-primed 2-5-year-olds (n=78), the immune response to the JE-CV vaccine persisted up to at least 5years after vaccination with a single dose of JE-CV, with all (n=78) children seroprotected at the year 5 visit (geometric mean titers [GMT]: 2521/dil). There was no decrease of seroprotection rate over time (100% at 6months post-vaccination and 96.8% (90.3-98.9) at 5yearspost-vaccination). In JE-vaccine-naïve toddlers, a protective immune response persisted up to at least 5years in 58.8% (50.9-66.4) after a single-dose administration of JE-CV (GMT 26.71/dil; sensitivity analysis). A single-dose of JE-CV as a booster following MBDV administration provided long-lasting immunity. In JE-vaccine-naïve toddlers, despite relatively high seroprotection rates persisting over time, a subsequent booster dose is recommended following a JE-CV primary vaccination for long-term protection. This study was registered on www.clinicaltrials.gov (NCT00621764). Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Detection of Schmallenberg virus antibody in equine population of Northern and Northeast of Iran

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    M. Rasekh

    2018-01-01

    Full Text Available Aim: Schmallenberg virus (SBV is a newly emerging virus in Simbu group that 1st time is reported in 2011 in Germany and now spread to Europe. The clinical signs of infection to this virus are fever, loss of appetite, reduced milk yield and in some cases, diarrhea and in pregnant animals congenital malformations in calves, lambs, and kid goats. Materials and Methods: In this study for a serologic survey of SBV, blood samples from 200 horse in different rural areas of the northern and northeast of Iran with the high equine population collected and were analyzed using an indirect ELISA test. Results: Based on our results 5% (n=10 of total 200 samples were positive for SBV antibody and 2% (n=4 was doubtful and 93% (n=186 was negative. There were no significant differences between age and sex and breed properties (p>0.05. Conclusion: This study demonstrated the presence of antibodies against the SBV on horse populations in Iran. The high population and activity of Culicoides biting midges and their proper living conditions, especially the areas of temperate and humid environmental conditions, are the possible causes of arboviruses related diseases seen in this country.

  8. Olympic Games Rio 2016 and the uninvited viruses: Potential consequences for Europe and North America

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    Salim Mattar

    2016-05-01

    Full Text Available In the Latin American tropics, we have witnessed the emergence of several pathogenic arboviruses in the last decade. These include Yellow Fever, West Nile virus, St. Louis encephalitis, Venezuelan equine encephalitis, Mayaro, Oropouche, Ilheus, and most recently, Chikungunya and Zika. Guillain-Barre syndrome (GBS, microcephaly and all the encephalitides, have been of concern to public health officials in Latin America since the arrival of emerging arboviruses. ¡Don‘t forget about dengue!

  9. BK Virus Encephalitis in HIV-Infected Patients: Case Report and Review

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    Luciana Antoniolli

    2017-01-01

    Full Text Available Encephalitis and meningitis due to BKPyV are unusual and emerging condition. Only a few cases of BKPyV encephalitis have been reported in hematopoietic stem cell transplant recipients, with the majority of cases presenting with concurrent hemorrhagic cystitis and HIV-infected patients. The authors report two HIV-infected patients with the diagnosis of BKPyV encephalitis and discuss the main clinical, diagnostic, and therapeutic aspects of this infection in patients with AIDS. Physicians should be aware to recognize the main clinical features and diagnose BKPyV central nervous infection in the setting of AIDS.

  10. Survey for hantaviruses, tick-borne encephalitis virus, and Rickettsia spp. in small rodents in Croatia.

    Science.gov (United States)

    Svoboda, Petra; Dobler, Gerhard; Markotić, Alemka; Kurolt, Ivan-Christian; Speck, Stephanie; Habuš, Josipa; Vucelja, Marko; Krajinović, Lidija Cvetko; Tadin, Ante; Margaletić, Josip; Essbauer, Sandra

    2014-07-01

    In Croatia, several rodent- and vector-borne agents are endemic and of medical importance. In this study, we investigated hantaviruses and, for the first time, tick-borne encephalitis virus (TBEV) and Rickettsia spp. in small wild rodents from two different sites (mountainous and lowland region) in Croatia. In total, 194 transudate and tissue samples from 170 rodents (A. flavicollis, n=115; A. agrarius, n=2; Myodes glareolus, n=53) were tested for antibodies by indirect immunofluorescence assays (IIFT) and for nucleic acids by conventional (hantaviruses) and real-time RT-/PCRs (TBEV and Rickettsia spp.). A total of 25.5% (24/94) of the rodents from the mountainous area revealed specific antibodies against hantaviruses. In all, 21.3% (20/94) of the samples from the mountainous area and 29.0% (9/31) from the lowland area yielded positive results for either Puumala virus (PUUV) or Dobrava-Belgrade virus (DOBV) using a conventional RT-PCR. All processed samples (n=194) were negative for TBEV by IIFT or real-time RT-PCR. Serological evidence of rickettsial infection was detected in 4.3% (4/94) rodents from the mountainous region. Another 3.2% (3/94) rodents were positive for Rickettsia spp. by real-time PCR. None of the rodents (n=76) from the lowland area were positive for Rickettsia spp. by real-time PCR. Dual infection of PUUV and Rickettsia spp. was found in one M. glareolus from the mountainous area by RT-PCR and real-time PCR, respectively. To our knowledge, this is the first detection of Rickettsia spp. in small rodents from Croatia. Phylogenetic analyses of S- and M-segment sequences obtained from the two study sites revealed well-supported subgroups in Croatian PUUV and DOBV. Although somewhat limited, our data showed occurrence and prevalence of PUUV, DOBV, and rickettsiae in Croatia. Further studies are warranted to confirm these data and to determine the Rickettsia species present in rodents in these areas.

  11. Engineering of Chimeric Protein Based on E Protein Domain III of Tick-Borne Encephalitis Virus and OmpF Porin of Yersinia pseudotuberculosis.

    Science.gov (United States)

    Stenkova, Anna M; Chopenko, Natalia S; Davydova, Ludmila A; Mazeika, Andrey N; Bystritskaya, Evgeniya P; Portnyagina, Olga Y; Anastyuk, Stanislav D; Kulbatskii, Dmitrii S; Lyukmanova, Ekaterina N; Dolgikh, Dmitriy A; Kostetsky, Eduard Y; Sanina, Nina M

    2017-07-24

    Tick-borne encephalitis poses a serious public health threat in the endemic regions. The disease treatment is restricted to symptomatic therapy, so great expectations are in the development of the prophylactic and therapeutic vaccines. The domain III of E protein of the tick-borne encephalitis virus is the main antigenic domain which includes virus-specific epitopes recognized by neutralizing antibodies. We have expressed, isolated and characterized the chimeric protein based on the fusion of domain III of E protein of the tick-borne encephalitis virus and bacterial porin OmpF from Yersinia pseudotuberculosis. The bacterial partner protein was used for decreasing toxicity and increasing immunogenicity of antigen. The chimeric protein was successfully expressed by the E. coli cells and purified using IMAC methodology. The purified protein was recognized with immunoblots by anti-E protein of tick-borne encephalitis virus monoclonal antibodies. Furthermore, the protein was able to elicit antibody response against domain III of E protein in immunized mice. The newly obtained chimeric antigen could be valuable for the development of the preventing tick-borne encephalitis subunit vaccines. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  12. Combination of an unbiased amplification method and a resequencing microarray for detecting and genotyping equine arteritis virus.

    Science.gov (United States)

    Hans, Aymeric; Gaudaire, Delphine; Manuguerra, Jean-Claude; Leon, Albertine; Gessain, Antoine; Laugier, Claire; Berthet, Nicolas; Zientara, Stephan

    2015-01-01

    This study shows that an unbiased amplification method applied to equine arteritis virus RNA significantly improves the sensitivity of the real-time reverse transcription-quantitative PCR (RT-qPCR) recommended by the World Organization for Animal Health. Twelve viral RNAs amplified using this method were hybridized on a high-density resequencing microarray for effective viral characterization. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  13. Zika virus-induced neurological critical illness in Latin America: Severe Guillain-Barre Syndrome and encephalitis.

    Science.gov (United States)

    Sebastián, Ugarte Ubiergo; Ricardo, Arenas Villamizar Angel; Alvarez, Bruno C; Cubides, Angela; Luna, Angélica F; Arroyo-Parejo, Max; Acuña, Cayri E; Quintero, Agamenón V; Villareal, Orlando Ch; Pinillos, Oscar S; Vieda, Elías; Bello, Manuel; Peña, Susana; Dueñas-Castell, Carmelo; Rodriguez, Gloria M V; Ranero, Jorge L M; López, Rosa L M; Olaya, Sandra G; Vergara, José C; Tandazo, Ana; Ospina, Juan P S; Leyton Soto, Igor M; Fowler, R A; Marshall, John C

    2017-08-09

    Zika virus (ZIKAV) is classically described as causing minor symptoms in adult patients, however neurologic complications have been recognized. The recent outbreak in Central and South America has resulted in serious illness in some adult patients. We report adult patients in Latin America diagnosed with ZIKAV infection admitted to Intensive Care Units (ICUs). Multicenter, prospective case series of adult patients with laboratory diagnosis of ZIKAV in 16 ICUs in 8 countries. Between December 1st 2015 and April 2nd 2016, 16 ICUs in 8 countries enrolled 49 critically ill patients with diagnosis of ZIKAV infection. We included 10 critically ill patients with ZIKAV infection, as diagnosed with RT-PCR, admitted to the ICU. Neurologic manifestations concordant with Guillain-Barre Syndrome (GBS) were present in all patients, although 2 evolved into an encephalitis-like picture. 2 cases died, one due to encephalitis, the other septic shock. Differing from what was usually reported, ZIKAV infection can result in life-threatening neurologic illness in adults, including GBS and encephalitis. Collaborative reporting to identify severe illness from an emerging pathogen can provide valuable insights into disease epidemiology and clinical presentation, and inform public health authorities about acute care priorities. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Investigation of the genotype III to genotype I shift in Japanese encephalitis virus and the impact on human cases.

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    Han, Na; Adams, James; Fang, Wei; Liu, Si-Qing; Rayner, Simon

    2015-08-01

    Japanese encephalitis is a mosquito borne disease and is the leading cause of viral encephalitis in the Asia-Pacific area. The causative agent, Japanese encephalitis virus (JEV) can be phylogenetically classified into five genotypes based on nucleotide sequence. In recent years, genotype I (GI) has displaced genotype III (GIII) as the dominant lineage, but the mechanisms behind this displacement event requires elucidation. In an earlier study, we compared host variation over time between the two genotypes and observed that GI appears to have evolved to achieve more efficient infection in hosts in the replication cycle, with the tradeoff of reduced infectivity in secondary hosts such as humans. To further investigate this phenomenon, we collected JEV surveillance data on human cases and, together with sequence data, and generated genotype/case profiles from seven Asia-Pacific countries and regions to characterize the GI/GIII displacement event. We found that, when comprehensive and consistent vaccination and surveillance data was available, and the GIII to GI shift occurred within a well-defined time period, there was a statistically significant drop in JEV human cases. Our findings provide further support for the argument that GI is less effective in infecting humans, who represent a dead end host. However, experimental investigation is necessary to confirm this hypothesis. The study highlights the value of alternative approaches to investigation of epidemics, as well as the importance of effective data collection for disease surveillance and control.

  15. Detection of Eastern Equine Encephalomyelitis Virus RNA in North American Snakes

    Science.gov (United States)

    Bingham, Andrea M.; Graham, Sean P.; Burkett-Cadena, Nathan D.; White, Gregory S.; Hassan, Hassan K.; Unnasch, Thomas R.

    2012-01-01

    The role of non-avian vertebrates in the ecology of eastern equine encephalomyelitis virus (EEEV) is unresolved, but mounting evidence supports a potential role for snakes in the EEEV transmission cycle, especially as over-wintering hosts. To determine rates of exposure and infection, we examined serum samples from wild snakes at a focus of EEEV in Alabama for viral RNA using quantitative reverse transcription polymerase chain reaction. Two species of vipers, the copperhead (Agkistrodon contortrix) and the cottonmouth (Agkistrodon piscivorus), were found to be positive for EEEV RNA using this assay. Prevalence of EEEV RNA was more frequent in seropositive snakes than seronegative snakes. Positivity for the quantitative reverse transcription polymerase chain reaction in cottonmouths peaked in April and September. Body size and sex ratios were not significantly different between infected and uninfected snakes. These results support the hypothesis that snakes are involved in the ecology of EEEV in North America, possibly as over-wintering hosts for the virus. PMID:23033405

  16. Epidemiology and genetic characterization of equine infectious anaemia virus strains isolated in Belgium in 2010.

    Science.gov (United States)

    Caij, A B; Tignon, M

    2014-10-01

    In January 2010, the United Kingdom notified cases of equine infectious anaemia (EIA) in two horses introduced from Belgium. The animals came from one assembly centre in Romania and had transited through Belgium with 16 other horses. Nine of them, bought by a Belgian horse breeder, were investigated in Belgium and revealed one additional EIA-positive animal. Afterwards, the Belgian Federal Agency for the Safety of the Food Chain (FASFC) organized a serological EIA survey of the horses introduced into Belgium from Romania between 2007 and 2009. Among the 95 horses identified, six additional serological positive cases were found that had been introduced into Belgium in 2008 (n = 4) and in 2009 (n = 2). The survey was extended to the horses in contact with the positive cases, but all contact animals were negative, indicating the absence of transmission. Virological examination performed on tissue samples collected from two seropositive animals demonstrated the presence of viral DNA of EIA virus. Phylogenetic analysis based on the sequences of EIA virus gag gene clustered the Belgian isolates with Romanian strains isolated in 2009. The presumption of a common Belgian origin could be rejected. © 2012 Blackwell Verlag GmbH.

  17. Structural model of the Rev regulatory protein from equine infectious anemia virus.

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    Yungok Ihm

    Full Text Available Rev is an essential regulatory protein in the equine infectious anemia virus (EIAV and other lentiviruses, including HIV-1. It binds incompletely spliced viral mRNAs and shuttles them from the nucleus to the cytoplasm, a critical prerequisite for the production of viral structural proteins and genomic RNA. Despite its important role in production of infectious virus, the development of antiviral therapies directed against Rev has been hampered by the lack of an experimentally-determined structure of the full length protein. We have used a combined computational and biochemical approach to generate and evaluate a structural model of the Rev protein. The modeled EIAV Rev (ERev structure includes a total of 6 helices, four of which form an anti-parallel four-helix bundle. The first helix contains the leucine-rich nuclear export signal (NES. An arginine-rich RNA binding motif, RRDRW, is located in a solvent-exposed loop region. An ERLE motif required for Rev activity is predicted to be buried in the core of modeled structure where it plays an essential role in stabilization of the Rev fold. This structural model is supported by existing genetic and functional data as well as by targeted mutagenesis of residues predicted to be essential for overall structural integrity. Our predicted structure should increase understanding of structure-function relationships in Rev and may provide a basis for the design of new therapies for lentiviral diseases.

  18. A long term study of goats naturally infected with caprine arthritis-encephalitis virus.

    Science.gov (United States)

    Hanson, J; Hydbring, E; Olsson, K

    1996-01-01

    The caprine arthritis-encephalitis virus (CAEV) is a big problem in dairy goat industry. Little is known about its characteristics in naturally infected goat herds. The aims of this study were: 1) to study how antibody expression, measured by agar gel immunodiffusion test (AGIDT), varied over time in naturally infected, seropositive goats, 2) to observe clinical signs in seropositive adult goats and 3) to follow seroconversion and gamma globulin concentration in goat kids artificially reared on cow milk replacement product only, compared to kids reared on untreated goat milk. The antibody expression pattern to the viral proteins gp135 and p28 varied in the individual goat and intermittent negative reactions were seen in 19 adult animals followed for 30-91 weeks. Four seropositive goats developed clinical symptoms with difficulties to move. However, no correlation between clinical signs and antibody expression pattern was seen. During the first 27 weeks of age no kid in the milk replacement reared group (N = 4) seroconverted, but 5 of the 7 kids fed goat milk occasionally showed a positive antibody reaction. The gamma globulin concentration was significantly higher in the goat milk fed group until the kids had become more than 19 weeks old. The results show that a great variation of the antibody pattern in individual goats occurs, and therefore the AGIDT is only reliable as a herd screening test. Frequent sampling is necessary to get reliable information about spreading of the CAEV in a naturally infected goat herd. Removing kids from their dams immediately after birth combined with segregation and artificial rearing protected them from CAEV infection. However their gamma globulin concentration was initially low.

  19. Diagnosis of Caprine Arthritis Encephalitis Virus infection in dairy goats by ELISA, PCR and Viral Culture.

    Science.gov (United States)

    Panneum, S; Rukkwamsuk, T

    2017-03-01

    For preventive and control strategies of Caprine Arthritis Encephalitis Virus (CAEV) infection in dairy goats, performance of the available diagnostic tests was described as one of the most important and necessary aspects. The study aimed at evaluating the diagnostic test performance, including PCR, ELISA and viral culture, for CAEV infection in dairy goats in Thailand. Blood samples of 29 dairy goats from five low- to medium-prevalence herds and one very low-prevalence herd were collected for PCR and ELISA methods. The performance of these two diagnostic methods was evaluated by comparing with cytopathic effects (CPE) in the co-cultivation of CAEV and primary synovial cells. Results indicated that sensitivity, specificity were, respectively, 69.6%, 100%, for PCR; and 95.7%, 83.3% for ELISA. The PCR assay tended to have lower sensitivity and higher specificity than ELISA. When multiple tests were applied, parallel testing provided sensitivity and specificity of 98.7% and 83.3%, while series testing showed sensitivity and specificity of 66.6% and 100% respectively. These results indicated that combination of ELISA and PCR provided some advantages and possibly offered optimal methods to detect CAEV-infected goats. Kappa value of the agreement between PCR and ELISA test was 0.34, indicating fair agreement. Regarding the possibility of antigenic variation between CAEV strains used in both PCR and ELISA assays, the actual circulating CAEV strain should be reviewed in order to develop and enhance the diagnostic tests using the CAE viral antigens derived from specific local strains of Thailand.

  20. Fatal Caprine arthritis encephalitis virus-like infection in 4 Rocky Mountain goats (Oreamnos americanus).

    Science.gov (United States)

    Patton, Kristin M; Bildfell, Robert J; Anderson, Mark L; Cebra, Christopher K; Valentine, Beth A

    2012-03-01

    Over a 3.5-year period, 4 Rocky Mountain goats (Oreamnos americanus), housed at a single facility, developed clinical disease attributed to infection by Caprine arthritis encephalitis virus (CAEV). Ages ranged from 1 to 10 years. Three of the goats, a 1-year-old female, a 2-year-old male, and a 5-year-old male, had been fed raw domestic goat milk from a single source that was later found to have CAEV on the premises. The fourth animal, a 10-year-old male, had not ingested domestic goat milk but had been housed with the other 3 Rocky Mountain goats. All 4 animals had clinical signs of pneumonia prior to death. At necropsy, findings in lungs included marked diffuse interstitial pneumonia characterized histologically by severe lymphoplasmacytic infiltrates with massive alveolar proteinosis, interstitial fibrosis, and type II pneumocyte hyperplasia. One animal also developed left-sided hemiparesis, and locally extensive lymphoplasmacytic myeloencephalitis was present in the cranial cervical spinal cord. Two animals had joint effusions, as well as severe lymphoplasmacytic and ulcerative synovitis. Immunohistochemical staining of fixed sections of lung tissue from all 4 goats, as well as spinal cord in 1 affected animal, and synovium from 2 affected animals were positive for CAEV antigen. Serology testing for anti-CAEV antibodies was positive in the 2 goats tested. The cases suggest that Rocky Mountain goats are susceptible to naturally occurring CAEV infection, that CAEV from domestic goats can be transmitted to this species through infected milk and by horizontal transmission, and that viral infection can result in clinically severe multisystemic disease.

  1. Prevalence of antibodies against tick-borne encephalitis virus in wild game from Saxony, Germany.

    Science.gov (United States)

    Balling, Anneliese; Plessow, Uta; Beer, Martin; Pfeffer, Martin

    2014-10-01

    Tick-borne encephalitis (TBE) is the most important tick-transmitted viral disease in Europe and is caused by the flavivirus TBE-virus (TBEV). In Germany TBE is unevenly distributed with the vast majority of cases occurring in the south in so-called risk areas defined as regions with an incidence of at least 1 case in 100,000 inhabitants. However, in low endemic areas with lesser TBE cases the respective risk assessment is hard to achieve. We therefore intend to use the prevalence of antibodies against TBEV in wildlife to trace TBEV endemic areas as a surrogate marker for the notification of human cases. This study was conducted in Saxony, Germany, where 34 autochthonous cases were reported since 2001, thereby not allowing a geographic allocation within the state. A total of 1,851 sera from wild boar and 35 sera from roe deer from all Saxon districts shot between April 2011 and March 2013 were screened for the presence of antibodies against TBEV. The overall seropositivity for Saxony was 10.5%. Among the wild boar sera, most positive samples could be found in the districts Meißen (23%) and Vogtlandkreis (20%) followed by Dresden (18%), Erzgebirgskreis and Görlitz (both 10%). We conclude that seroprevalence studies in game animals represent a promising surrogate marker and should be considered for future determination of risk areas. Although we are currently unable to explain the discrepancy of the few human cases and the high seroprevalence in some districts, vaccination against TBE should be considered for people planning outdoor activities in Dresden, Meißen or Vogtlandkreis. Copyright © 2014 Elsevier GmbH. All rights reserved.

  2. A novel immunochromatographic test applied to a serological survey of Japanese encephalitis virus on pig farms in Korea.

    Directory of Open Access Journals (Sweden)

    Go-Woon Cha

    Full Text Available Among vertebrate species, pigs are a major amplifying host of Japanese encephalitis virus (JEV and measuring their seroconversion is a reliable indicator of virus activity. Traditionally, the hemagglutination inhibition test has been used for serological testing in pigs; however, it has several limitations and, thus, a more efficient and reliable replacement test is required. In this study, we developed a new immunochromatographic test for detecting antibodies to JEV in pig serum within 15 min. Specifically, the domain III region of the JEV envelope protein was successfully expressed in soluble form and used for developing the immunochromatographic test. The test was then applied to the surveillance of Japanese encephalitis (JE in Korea. We found that our immunochromatographic test had good sensitivity (84.8% and specificity (97.7% when compared with an immunofluorescence assay used as a reference test. During the surveillance of JE in Korea in 2012, the new immunochromatographic test was used to test the sera of 1,926 slaughtered pigs from eight provinces, and 228 pigs (11.8% were found to be JEV-positive. Based on these results, we also produced an activity map of JEV, which marked the locations of pig farms in Korea that tested positive for the virus. Thus, the immunochromatographic test reported here provides a convenient and effective tool for real-time monitoring of JEV activity in pigs.

  3. Molecular detection and phylogenetic analysis of tick-borne encephalitis virus in rodents captured in the transdanubian region of Hungary.

    Science.gov (United States)

    Pintér, Réka; Madai, Mónika; Horváth, Győző; Németh, Viktória; Oldal, Miklós; Kemenesi, Gábor; Dallos, Bianka; Bányai, Krisztián; Jakab, Ferenc

    2014-08-01

    Abstract Tick-borne encephalitis virus (TBEV) infection is a common zoonotic disease affecting humans in Europe and Asia. To determine whether TBEV is present in small mammalian hosts in Hungary, liver samples of wild rodents were tested for TBEV RNA. Over a period of 7 years, a total of 405 rodents were collected at five different geographic locations of the Transdanubian region. TBEV nucleic acid was identified in four rodent species: Apodemus agrarius, A. flavicollis, Microtus arvalis, and Myodes glareolus. Out of the 405 collected rodents, 17 small mammals (4.2%) were positive for TBEV. The present study provides molecular evidence and sequence data of TBEV from rodents in Hungary.

  4. Viral Infection of the Central Nervous System and Neuroinflammation Precede Blood-Brain Barrier Disruption during Japanese Encephalitis Virus Infection.

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    Li, Fang; Wang, Yueyun; Yu, Lan; Cao, Shengbo; Wang, Ke; Yuan, Jiaolong; Wang, Chong; Wang, Kunlun; Cui, Min; Fu, Zhen F

    2015-05-01

    Japanese encephalitis is an acute zoonotic, mosquito-borne disease caused by Japanese encephalitis virus (JEV). Japanese encephalitis is characterized by extensive inflammation in the central nervous system (CNS) and disruption of the blood-brain barrier (BBB). However, the pathogenic mechanisms contributing to the BBB disruption are not known. Here, using a mouse model of intravenous JEV infection, we show that virus titers increased exponentially in the brain from 2 to 5 days postinfection. This was accompanied by an early, dramatic increase in the level of inflammatory cytokines and chemokines in the brain. Enhancement of BBB permeability, however, was not observed until day 4, suggesting that viral entry and the onset of inflammation in the CNS occurred prior to BBB damage. In vitro studies revealed that direct infection with JEV could not induce changes in the permeability of brain microvascular endothelial cell monolayers. However, brain extracts derived from symptomatic JEV-infected mice, but not from mock-infected mice, induced significant permeability of the endothelial monolayer. Consistent with a role for inflammatory mediators in BBB disruption, the administration of gamma interferon-neutralizing antibody ameliorated the enhancement of BBB permeability in JEV-infected mice. Taken together, our data suggest that JEV enters the CNS, propagates in neurons, and induces the production of inflammatory cytokines and chemokines, which result in the disruption of the BBB. Japanese encephalitis (JE) is the leading cause of viral encephalitis in Asia, resulting in 70,000 cases each year, in which approximately 20 to 30% of cases are fatal, and a high proportion of patients survive with serious neurological and psychiatric sequelae. Pathologically, JEV infection causes an acute encephalopathy accompanied by BBB dysfunction; however, the mechanism is not clear. Thus, understanding the mechanisms of BBB disruption in JEV infection is important. Our data demonstrate

  5. EXPRESSION AND SELF-ASSEMBLY OF NORWALK VIRUS CAPSID PROTEIN FROM VENEZUELAN EQUINE ENCEPHALITIS VIRUS REPLICONS. (R826139)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  6. Pathogenic and Genotypic Characterization of a Japanese Encephalitis Virus Isolate Associated with Reproductive Failure in an Indian Pig Herd.

    Science.gov (United States)

    Desingu, P A; Ray, Pradeep K; Patel, B H M; Singh, R; Singh, R K; Saikumar, G

    2016-01-01

    India is endemic to Japanese encephalitis virus (JEV) and recurrent outbreaks occur mainly in rice growing areas. Pigs are considered to be the amplifying host for JEV and infection in gestating pigs results in reproductive failure. Most studies conducted on JEV infection in Indian pigs have been serological surveys and very little is known about JEV genotypes circulating in pigs. So the potential risk posed by pigs in JEV transmission and the genetic relationship between viruses circulating in pigs, mosquitoes and humans is poorly understood. This study was conducted in pigs with a history of reproductive failure characterized by stillborn piglets with neuropathological lesions. Japanese encephalitis (JE) suspected brain specimens inoculated intracerebrally into mice and Vero cells resulted in successful isolation of JEV/SW/IVRI/395A/2014. Clinicopathological observations in infected mice, demonstration of JEV antigen in brain, and analysis of the envelope protein identified the swine isolate as being neurovirulent. Phylogenetic analysis based on prM and E gene sequences showed that it belonged to genotype III. This swine isolate was closely related to JEV associated with the 2005 outbreak in India and JaoArS982 from Japan. Phylogenetic analysis of JEV strains collected between 1956 and 2014 in India categorized the GIII viruses into different clades blurring their spatial distribution, which has been discernible in the previous century. Isolation of JEV from stillborn piglets and its close genetic relationship with viruses detected at least three decades ago in humans and mosquitoes in Japan suggests that the virus may have been circulating among Indian pigs for several decades. The close similarity between the present swine isolate and those detected in humans affected in the 2005 outbreak in Uttar Pradesh, India, suggests the need for more intensive surveillance of pigs and implementation of suitable strategies to control JE in India.

  7. Defensive Perimeter in the Central Nervous System: Predominance of Astrocytes and Astrogliosis during Recovery from Varicella-Zoster Virus Encephalitis.

    Science.gov (United States)

    Carpenter, John E; Clayton, Amy C; Halling, Kevin C; Bonthius, Daniel J; Buckingham, Erin M; Jackson, Wallen; Dotzler, Steven M; Card, J Patrick; Enquist, Lynn W; Grose, Charles

    2015-10-21

    Varicella-zoster virus (VZV) is a highly neurotropic virus that can cause infections in both the peripheral nervous system and the central nervous system. Several studies of VZV reactivation in the peripheral nervous system (herpes zoster) have been published, while exceedingly few investigations have been carried out in a human brain. Notably, there is no animal model for VZV infection of the central nervous system. In this report, we characterized the cellular environment in the temporal lobe of a human subject who recovered from focal VZV encephalitis. The approach included not only VZV DNA/RNA analyses but also a delineation of infected cell types (neurons, microglia, oligodendrocytes, and astrocytes). The average VZV genome copy number per cell was 5. Several VZV regulatory and structural gene transcripts and products were detected. When colocalization studies were performed to determine which cell types harbored the viral proteins, the majority of infected cells were astrocytes, including aggregates of astrocytes. Evidence of syncytium formation within the aggregates included the continuity of cytoplasm positive for the VZV glycoprotein H (gH) fusion-complex protein within a cellular profile with as many as 80 distinct nuclei. As with other causes of brain injury, these results suggested that astrocytes likely formed a defensive perimeter around foci of VZV infection (astrogliosis). Because of the rarity of brain samples from living humans with VZV encephalitis, we compared our VZV results with those found in a rat encephalitis model following infection with the closely related pseudorabies virus and observed similar perimeters of gliosis. Investigations of VZV-infected human brain from living immunocompetent human subjects are exceedingly rare. Therefore, much of our knowledge of VZV neuropathogenesis is gained from studies of VZV-infected brains obtained at autopsy from immunocompromised patients. These are not optimal samples with which to investigate a

  8. mosGCTL-7, a C-Type Lectin Protein, Mediates Japanese Encephalitis Virus Infection in Mosquitoes.

    Science.gov (United States)

    Liu, Ke; Qian, Yingjuan; Jung, Yong-Sam; Zhou, Bin; Cao, Ruibing; Shen, Ting; Shao, Donghua; Wei, Jianchao; Ma, Zhiyong; Chen, Puyan; Zhu, Huaimin; Qiu, Yafeng

    2017-05-15

    Japanese encephalitis virus (JEV) is an arthropod-borne flavivirus prevalent in Asia and the Western Pacific and is the leading cause of viral encephalitis. JEV is maintained in a transmission cycle between mosquitoes and vertebrate hosts, but the molecular mechanisms by which the mosquito vector participates in transmission are unclear. We investigated the expression of all C-type lectins during JEV infection in Aedes aegypti The C-type lectin mosquito galactose-specific C-type lectin 7 (mosGCTL-7) (VectorBase accession no. AAEL002524) was significantly upregulated by JEV infection and facilitated infection in vivo and in vitro mosGCTL-7 bound to the N-glycan at N154 on the JEV envelope protein. This recognition of viral N-glycan by mosGCTL-7 is required for JEV infection, and we found that this interaction was Ca(2+) dependent. After mosGCTL-7 bound to the glycan, mosPTP-1 bound to mosGCTL-7, promoting JEV entry. The viral burden in vivo and in vitro was significantly decreased by mosPTP-1 double-stranded RNA (dsRNA) treatment, and infection was abolished by anti-mosGCTL-7 antibodies. Our results indicate that the mosGCTL-7/mosPTP-1 pathway plays a key role in JEV infection in mosquitoes. An improved understanding of the mechanisms underlying flavivirus infection in mosquitoes will provide further opportunities for developing new strategies to control viral dissemination in nature.IMPORTANCE Japanese encephalitis virus is a mosquito-borne flavivirus and is the primary cause of viral encephalitis in the Asia-Pacific region. Twenty-four countries in the WHO Southeast Asia and Western Pacific regions have endemic JEV transmission, which exposes >3 billion people to the risks of infection, although JEV primarily affects children. C-type lectins are host factors that play a role in flavivirus infection in humans, swine, and other mammals. In this study, we investigated C-type lectin functions in JEV-infected Aedes aegypti and Culex pipiens pallens mosquitoes and

  9. Transcriptional Immunoprofiling at the Tick-Virus-Host Interface during Early Stages of Tick-Borne Encephalitis Virus Transmission

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    Saravanan Thangamani

    2017-12-01

    Full Text Available Emerging and re-emerging diseases transmitted by blood feeding arthropods are significant global public health problems. Ticks transmit the greatest variety of pathogenic microorganisms of any blood feeding arthropod. Infectious agents transmitted by ticks are delivered to the vertebrate host together with saliva at the bite site. Tick salivary glands produce complex cocktails of bioactive molecules that facilitate blood feeding and pathogen transmission by modulating host hemostasis, pain/itch responses, wound healing, and both innate and adaptive immunity. In this study, we utilized Illumina Next Generation Sequencing to characterize the transcriptional immunoprofile of cutaneous immune responses to Ixodes ricinus transmitted tick-borne encephalitis virus (TBEV. A comparative immune gene expression analysis of TBEV-infected and uninfected tick feeding sites was performed. Our analysis reveals that ticks create an inflammatory environment at the bite site during the first 3 h of feeding, and significant differences in host responses were observed between TBEV-infected and uninfected tick feeding. Gene-expression analysis reveals modulation of inflammatory genes after 1 and 3 h of TBEV-infected tick feeding. Transcriptional levels of genes specific to chemokines and cytokines indicated a neutrophil-dominated immune response. Immunohistochemistry of the tick feeding site revealed that mononuclear phagocytes and fibroblasts are the primary target cells for TBEV infection and did not detect TBEV antigens in neutrophils. Together, the transcriptional and immunohistochemistry results suggest that early cutaneous host responses to TBEV-infected tick feeding are more inflammatory than expected and highlight the importance of inflammatory chemokine and cytokine pathways in tick-borne flavivirus transmission.

  10. Subacute herpes simplex virus type 1 encephalitis as an initial presentation of chronic lymphocytic leukemia and multiple sclerosis: a case report

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    Corman Lourdes C

    2011-02-01

    Full Text Available Abstract Introduction Herpes simplex virus type 1 encephalitis presents acutely in patients who are immunocompetent. We report what we believe to be the first published case of a subacute course of herpes simplex virus type 1 encephalitis in a patient with asymptomatic chronic lymphocytic leukemia who subsequently developed multiple sclerosis. Case presentation A 49-year-old Caucasian woman with a history of fever blisters presented to the emergency department with a history of left temporal headache for four weeks, and numbness of the left face and leg for two weeks. A complete blood count revealed white blood cell count of 11,820 cells/mL, with an absolute lymphocyte count of 7304 cells/mL. The cerebrospinal fluid contained 6 white blood cells/μL, 63 red blood cells/μL, 54 mg glucose/dL, and 49 mg total protein/dL. Magnetic resonance imaging of the brain revealed meningoencephalitis and bilateral ventriculitis. Cerebrospinal fluid polymerase chain reaction for herpes simplex virus type 1 was positive, and the patient's symptoms resolved after ten days of treatment with parenteral aciclovir. Incidental findings on peripheral blood smear and flow cytometry testing confirmed chronic lymphocytic leukemia. One month later, she developed bilateral numbness of the hands and feet; a repeat cerebrospinal fluid polymerase chain reaction for herpes simplex virus type 1 at this time was negative. A repeat magnetic resonance imaging scan showed an expansion of the peri-ventricular lesions, and the cerebrospinal fluid contained elevated oligoclonal bands and myelin basic protein. A brain biopsy revealed gliosis consistent with multiple sclerosis, and the patient responded to treatment with high-dose parenteral steroids. Conclusion Herpes simplex virus type 1 encephalitis is a rare presentation of chronic lymphocytic leukemia. Our patient had an atypical, subacute course, presumably due to immunosuppression from chronic lymphocytic leukemia. This unusual

  11. Influence of the CCR-5/MIP-1 α Axis in the Pathogenesis of Rocio Virus Encephalitis in a Mouse Model

    Science.gov (United States)

    Chávez, Juliana H.; França, Rafael F. O.; Oliveira, Carlo J. F.; de Aquino, Maria T. P.; Farias, Kleber J. S.; Machado, Paula R. L.; de Oliveira, Thelma F. M.; Yokosawa, Jonny; Soares, Edson G.; da Silva, João S.; da Fonseca, Benedito A. L.; Figueiredo, Luiz T. M.

    2013-01-01

    Rocio virus (ROCV) caused an outbreak of human encephalitis during the 1970s in Brazil and its immunopathogenesis remains poorly understood. CC-chemokine receptor 5 (CCR5) is a chemokine receptor that binds to macrophage inflammatory protein (MIP-1 α). Both molecules are associated with inflammatory cells migration during infections. In this study, we demonstrated the importance of the CCR5 and MIP-1 α, in the outcome of viral encephalitis of ROCV-infected mice. CCR5 and MIP-1 α knockout mice survived longer than wild-type (WT) ROCV-infected animals. In addition, knockout mice had reduced inflammation in the brain. Assessment of brain viral load showed mice virus detection five days post-infection in wild-type and CCR5−/− mice, while MIP-1 α−/− mice had lower viral loads seven days post-infection. Knockout mice required a higher lethal dose than wild-type mice as well. The CCR5/MIP-1 α axis may contribute to migration of infected cells to the brain and consequently affect the pathogenesis during ROCV infection. PMID:24080631

  12. Prevalence of tick-borne encephalitis virus (TBEV) RNA in Dermacentor reticulatus ticks from natural and urban environment, Poland.

    Science.gov (United States)

    Biernat, Beata; Karbowiak, Grzegorz; Werszko, Joanna; Stańczak, Joanna

    2014-12-01

    Tick-borne encephalitis virus (TBEV) (Flaviviridae, Flavivirus) is an arthropod-borne virus, an etiologic agent of tick-borne encephalitis (TBE), a human infection involving the central nervous system. The disease is endemic in a large region in Eurasia, where it is transmitted mainly by Ixodes ricinus and Ixodes persulcatus ticks. It is known that also Dermacentor reticulatus is involved in circulation of TBEV. However, the current knowledge of D. reticulatus importance in TBE epidemiology is still insufficient. A total of 471 adult D. reticulatus ticks were collected by flagging vegetation in the Białowieża Primeval Forest, Biebrza National Park, Masurian Landscape Park (North-Eastern Poland) and in the city of Warsaw in the years 2007-2010. All collected ticks were examined individually for the presence of RNA of TBEV using nested RT-PCR assay. Positive results were noted in all investigated localities with the infection rate ranging from 0.99 to 12.5 % with a total mean of 2.12 %. The difference in the percentage of infective males and females was not statistically significant.

  13. Capsid, membrane and NS3 are the major viral proteins involved in autophagy induced by Japanese encephalitis virus.

    Science.gov (United States)

    Wang, Xiujin; Hou, Lei; Du, Jige; Zhou, Lei; Ge, Xinna; Guo, Xin; Yang, Hanchun

    2015-08-05

    Japanese encephalitis virus (JEV) is an important zoonotic pathogen causing viral encephalitis in human and reproductive failure in pigs. In the present study, we first examined the autophagy induced by JEV infection in host cells, and then analyzed the JEV proteins involving in autophagy induction, and further investigated the relationship between viral protein and immunity-related GTPases M (IRGM). Our results showed that JEV infection could induce autophagy in host cells and autophagy promoted the replication of JEV in vitro; the cells transfected with individual plasmid that was expressing C, M and NS3 had a significantly higher conversion of LC3-I/II, and enhanced LC3 signals with the fluorescence punctuates accumulation which was completely co-localized with LC3 and increased number of autophagosomes-like vesicles, suggesting that C, M and NS3 are the major viral proteins involving in autophagy induction upon JEV infection; the virus titer in the cells treated by the siRNA specific for IRGM had a significant decrease, and the NS3 signals in the cells transfected with the plasmid that was expressing NS3 were completely co-localized with the IRGM signals, suggesting that the NS3 of JEV could target IRGM which may play a role in the replication of JEV. Our findings help to understand the role of autophagy in JEV and other flaviviruses infections. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Experimental exposure of pregnant mares to the asinine-94 strain of equine arteritis virus

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    J.T. Paweska

    1997-07-01

    Full Text Available Clinical, virological and serological responses were evaluated in 10 pregnant mares after different challenge exposures to the asinine-94 strain of equine arteritis virus (EAV. The outcome of maternal infection on the progeny was also investigated. Mares were inoculated intranasally (n = 4, intramuscularly (n = 2, intravenously (n = 1, or contact-exposed (n = 3. All inoculated mares developed pyrexia, 5 showed mild clinical signs related to EAV infection and 2 remained asymptomatic. Viraemia was detected in all the inoculated animals and shedding of virus from the respiratory tract occurred in 6. Five mares were re-challenged intranasally 7 and 15 weeks after inoculation. Clinical signs of the disease in these mares were limited to mild conjunctivitis. After re-challenge, virus was recovered from buffy coat cultures of 2 mares 2-6 days after re-infection. EAV was not recovered from colostrum and milk samples during the 1st week post partum. All inoculated mares seroconverted to EAV 8-12 days post inoculation and also seroconverted after re-challenge. No clinical signs of EAV infection were observed in the 3 mares kept in close contact during the post-inoculation and re-challenge periods. Serum neutralising antibody to the virus was detected in 1 in-contact mare only, while a detectable concentration of specific IgG was found by ELISA in the colostrum of 1 of the other in-contact mares. Eight of the mares gave birth to clinically normal foals, although 1 was born prematurely. Shortly after birth, 7 foals developed fever and variable clinical signs; 5 foals became septicaemic and 3 of them died 2-5 days after birth, while the remaining 2 were euthanased at 1 month of age. EAV was not recovered from the placenta, from buffy coat fractions of blood collected from foals immediately after birth and 1-3 days later, or from a range of tissues taken from the 3 foals that died and 2 that were euthanased. Virus was not isolated from tissues collected from

  15. Tick-borne encephalitis virus infects human brain microvascular endothelial cells without compromising blood-brain barrier integrity.

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    Palus, Martin; Vancova, Marie; Sirmarova, Jana; Elsterova, Jana; Perner, Jan; Ruzek, Daniel

    2017-07-01

    Alteration of the blood-brain barrier (BBB) is a hallmark of tick-borne encephalitis (TBE), a life-threating human viral neuroinfection. However, the mechanism of BBB breakdown during TBE, as well as TBE virus (TBEV) entry into the brain is unclear. Here, primary human microvascular endothelial cells (HBMECs) were infected with TBEV to study interactions with the BBB. Although the number of infected cells was relatively low in culture (10 6 pfu/ml). Infection did not induce any significant changes in the expression of key tight junction proteins or upregulate the expression of cell adhesion molecules, and did not alter the highly organized intercellular junctions between HBMECs. In an in vitro BBB model, the virus crossed the BBB via a transcellular pathway without compromising the integrity of the cell monolayer. The results indicate that HBMECs may support TBEV entry into the brain without altering BBB integrity. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Identifying the Conditions Under Which Antibodies Protect Against Infection by Equine Infectious Anemia Virus

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    Elissa J. Schwartz

    2014-05-01

    Full Text Available The ability to predict the conditions under which antibodies protect against viral infection would transform our approach to vaccine development. A more complete understanding is needed of antibody protection against lentivirus infection, as well as the role of mutation in resistance to an antibody vaccine. Recently, an example of antibody-mediated vaccine protection has been shown via passive transfer of neutralizing antibodies before equine infectious anemia virus (EIAV infection of horses with severe combined immunodeficiency (SCID. Viral dynamic modeling of antibody protection from EIAV infection in SCID horses may lead to insights into the mechanisms of control of infection by antibody vaccination. In this work, such a model is constructed in conjunction with data from EIAV infection of SCID horses to gain insights into multiple strain competition in the presence of antibody control. Conditions are determined under which wild-type infection is eradicated with the antibody vaccine. In addition, a three-strain competition model is considered in which a second mutant strain may coexist with the first mutant strain. The conditions that permit viral escape by the mutant strains are determined, as are the effects of variation in the model parameters. This work extends the current understanding of competition and antibody control in lentiviral infection, which may provide insights into the development of vaccines that stimulate the immune system to control infection effectively.

  17. A curious coincidence: mosquito biodiversity and the limits of the Japanese encephalitis virus in Australasia

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    Russell Richard C

    2007-06-01

    Full Text Available Abstract Background The mosquito Culex annulirostris Skuse (Diptera: Culicidae is the major vector of endemic arboviruses in Australia and is also responsible for the establishment of the Japanese encephalitis virus (JEV in southern Papua New Guinea (PNG as well as its incursions into northern Australia. Papua New Guinea and mainland Australia are separated by a small stretch of water, the Torres Strait, and its islands. While there has been regular JEV activity on these islands, JEV has not established on mainland Australia despite an abundance of Cx. annulirostris and porcine amplifying hosts. Despite the public health significance of this mosquito and the fact that its adults show overlapping morphology with close relative Cx. palpalis Taylor, its evolution and genetic structure remain undetermined. We address a hypothesis that there is significant genetic diversity in Cx. annulirostris and that the identification of this diversity will shed light on the paradox that JEV can cycle on an island 70 km from mainland Australia while not establishing in Australia itself. Results We sequenced 538 bp of the mitochondrial DNA cytochrome oxidase I gene from 273 individuals collected from 43 localities in Australia and the southwest Pacific region to describe the phylogeography of Cx. annulirostris and its sister species Cx. palpalis. Maximum Likelihood and Bayesian analyses reveal supporting evidence for multiple divergent lineages that display geographic restriction. Culex palpalis contained three divergent lineages geographically restricted to southern Australia, northern Australia and Papua New Guinea (PNG. Culex annulirostris contained five geographically restricted divergent lineages, with one lineage restricted to the Solomon Islands and two identified mainly within Australia while two other lineages showed distributions in PNG and the Torres Strait Islands with a southern limit at the top of Australia's Cape York Peninsula. Conclusion The

  18. Immunoblot Profile as Predictor of Toxoplasmic Encephalitis in Patients Infected with Human Immunodeficiency Virus

    Science.gov (United States)

    Leport, Catherine; Franck, Jacqueline; Chene, Genevieve; Derouin, Francis; Ecobichon, Jean-Luc; Pueyo, Sophie; Miro, Jose M.; Luft, Benjamin J.; Morlat, Philippe; Dumon, Henri

    2001-01-01

    In order to define more accurately human immunodeficiency virus-infected patients at risk of developing toxoplasmic encephalitis (TE), we assessed the prognostic significance of the anti-Toxoplasma gondii immunoglobulin G (IgG) immunoblot profile, in addition to AIDS stage, a CD4+ cell count <50/mm3, and an antibody titer ≥150 IU/ml, in patients with CD4 cell counts <200/mm3 and seropositive for T. gondii. Baseline serum samples from 152 patients included in the placebo arm of the ANRS 005-ACTG 154 trial (pyrimethamine versus placebo) were used. The IgG immunoblot profile was determined using a Toxoplasma lysate and read using the Kodak Digital Science 1D image analysis software. Mean follow-up was 15.1 months, and the 1-year incidence of TE was 15.9%. The cumulative probability of TE varied according to the type and number of anti-T. gondii IgG bands and reached 65% at 12 months for patients with IgG bands of 25 and 22 kDa. In a Cox model adjusted for age, gender, Centers for Disease Control and Prevention (CDC) clinical stage, and CD4 and CD8 cell counts, the incidence of TE was higher when the IgG 22-kDa band (hazard ratio [HR] = 5.4; P < 0.001), the IgG 25-kDa band (HR = 4.7; P < 0.001), or the IgG 69-kDa band (HR = 3.4; P < 0.001) was present and was higher for patients at CDC stage C (HR = 4.9; P < 0.001). T. gondii antibody titer and CD4 cell count were not predictive of TE. Thus, detection of IgG bands of 25, 22, and/or 69 kDa may be helpful for deciding when primary prophylaxis for TE should be started or discontinued, especially in the era of highly active antiretroviral therapy. PMID:11329461

  19. Biochemical characterization of a recombinant Japanese encephalitis virus RNA-dependent RNA polymerase

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    Kim Chan-Mi

    2007-07-01

    Full Text Available Abstract Background Japanese encephalitis virus (JEV NS5 is a viral nonstructural protein that carries both methyltransferase and RNA-dependent RNA polymerase (RdRp domains. It is a key component of the viral RNA replicase complex that presumably includes other viral nonstructural and cellular proteins. The biochemical properties of JEV NS5 have not been characterized due to the lack of a robust in vitro RdRp assay system, and the molecular mechanisms for the initiation of RNA synthesis by JEV NS5 remain to be elucidated. Results To characterize the biochemical properties of JEV RdRp, we expressed in Escherichia coli and purified an enzymatically active full-length recombinant JEV NS5 protein with a hexahistidine tag at the N-terminus. The purified NS5 protein, but not the mutant NS5 protein with an Ala substitution at the first Asp of the RdRp-conserved GDD motif, exhibited template- and primer-dependent RNA synthesis activity using a poly(A RNA template. The NS5 protein was able to use both plus- and minus-strand 3'-untranslated regions of the JEV genome as templates in the absence of a primer, with the latter RNA being a better template. Analysis of the RNA synthesis initiation site using the 3'-end 83 nucleotides of the JEV genome as a minimal RNA template revealed that the NS5 protein specifically initiates RNA synthesis from an internal site, U81, at the two nucleotides upstream of the 3'-end of the template. Conclusion As a first step toward the understanding of the molecular mechanisms for JEV RNA replication and ultimately for the in vitro reconstitution of viral RNA replicase complex, we for the first time established an in vitro JEV RdRp assay system with a functional full-length recombinant JEV NS5 protein and characterized the mechanisms of RNA synthesis from nonviral and viral RNA templates. The full-length recombinant JEV NS5 will be useful for the elucidation of the structure-function relationship of this enzyme and for the

  20. Infiltration Pattern of Blood Monocytes into the Central Nervous System during Experimental Herpes Simplex Virus Encephalitis.

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    Rafik Menasria

    Full Text Available The kinetics and distribution of infiltrating blood monocytes into the central nervous system and their involvement in the cerebral immune response together with resident macrophages, namely microglia, were evaluated in experimental herpes simplex virus 1 (HSV-1 encephalitis (HSE. To distinguish microglia from blood monocyte-derived macrophages, chimeras were generated by conditioning C57BL/6 recipient mice with chemotherapy regimen followed by transplantation of bone morrow-derived cells that expressed the green fluorescent protein. Mice were infected intranasally with a sub-lethal dose of HSV-1 (1.2 x 10(6 plaque forming units. Brains were harvested prior to and on days 4, 6, 8 and 10 post-infection for flow cytometry and immunohistochemistry analysis. The amounts of neutrophils (P < 0.05 and "Ly6C hi" inflammatory monocytes (P < 0.001 significantly increased in the CNS compared to non-infected controls on day 6 post-infection, which corresponded to more severe clinical signs of HSE. Levels decreased on day 8 for both leukocytes subpopulations (P < 0.05 for inflammatory monocytes compared to non-infected controls to reach baseline levels on day 10 following infection. The percentage of "Ly6C low" patrolling monocytes significantly increased (P < 0.01 at a later time point (day 8, which correlated with the resolution phase of HSE. Histological analysis demonstrated that blood leukocytes colonized mostly the olfactory bulb and the brainstem, which corresponded to regions where HSV-1 particles were detected. Furthermore, infiltrating cells from the monocytic lineage could differentiate into activated local tissue macrophages that express the microglia marker, ionized calcium-binding adaptor molecule 1. The lack of albumin detection in the brain parenchyma of infected mice showed that the infiltration of blood leukocytes was not necessarily related to a breakdown of the blood-brain barrier but could be the result of a functional recruitment. Thus

  1. A comparative analysis on the physicochemical properties of tick-borne encephalitis virus envelope protein residues that affect its antigenic properties

    Czech Academy of Sciences Publication Activity Database

    Bukin, Y. S.; Dzhioev, Y.; Tkachev, S. E.; Kozlova, I.; Paramonov, A. I.; Růžek, Daniel; Qu, Z.; Zlobin, V. I.

    2017-01-01

    Roč. 238, JUN 15 (2017), s. 124-132 ISSN 0168-1702 Institutional support: RVO:60077344 Keywords : tick-borne encephalitis virus * E protein * physicochemical properties amino acid residue * antigen * antibody Subject RIV: EE - Microbiology, Virology Impact factor: 2.628, year: 2016

  2. La Crosse Encephalitis Virus Infection in Field-Collected Aedes albopictus, Aedes japonicus, and Aedes triseriatus in Tennessee.

    Science.gov (United States)

    Westby, Katie M; Fritzen, Charissa; Paulsen, Dave; Poindexter, Stephanie; Moncayo, Abelardo C

    2015-09-01

    La Crosse virus (LACV) is a mosquito-borne virus and a major cause of pediatric encephalitis in the USA. La Crosse virus emerged in Tennessee and other states in the Appalachian region in 1997. We investigated LACV infection rates and seasonal abundances of the native mosquito vector, Aedes triseriatus, and 2 recently introduced mosquito species, Ae. albopictus and Ae. japonicus, in an emerging disease focus in Tennessee. Mosquitoes were collected using multiple trapping methods specific for Aedes mosquitoes at recent human case sites. Mosquito pools were tested via reverse transcriptase-polymerase chain reaction (RT-PCR) of the S segment to detect multiple Bunyamwera and California serogroup viruses, including LACV, as well as real-time RT-PCR of the M segment. A total of 54 mosquito pools were positive, including wild-caught adult females and laboratory-reared adults, demonstrating transovarial transmission in all 3 species. Maximum likelihood estimates (per 1,000 mosquitoes) were 2.72 for Ae. triseriatus, 3.01 for Ae. albopictus, and 0.63 for Ae. japonicus. We conclude that Ae. triseriatus and Ae. albopictus are important LACV vectors and that Ae. japonicus also may be involved in virus maintenance and transmission.

  3. [Immunochip for differentiation of IgG to tick-borne encephalitis and West Nile fever viruses].

    Science.gov (United States)

    Pomelova, V G; Bychenkova, T A; Bekman, N I; Osin, N S

    2010-01-01

    To demonstrate the possibility of development of test based on phosphorescent analysis (PHOSPHAN) for simultaneous identification and differentiation of specific IgG to tick-borne encephalitis (TBE) and West Nile fever (WNF) viruses. Twenty six serum samples from patients with TBE, twenty five from WNF, and sixty six fromclinically healthy donors were used for the study. Immunologic analysis was performed in plate wells with active microzones "printed" on the wells' bottom and corresponding the complex of virus-specific antigens with immobilized monoclonal antibodies; internal control of specificity was included in each well. Species specificity of antibodies was determined on the basis of not less than 2-fold elevation of value of positivity coefficient (P/N) of sample studied with homologous antigen compared to heterologous one. PHOSPHAN provides simultaneous detection of IgG in human serum to two related flaviviruses: TBE and WNF viruses. Usage of P/N criterion assessed with homologous and heterologous antigen allowed correct determination of species specificity of antibodies in 90% of serum samples from patients with TBE and WNF CONCLUSION: PHOSPHAN allows to detect and differentiate IgG to TBE and WNF viruses during testing of one serum sample in one plate well without decrease of sensitivity compared to enzyme immunoassay with separated testing of samples on two viruses. This provides savings of biomaterial, which is an advantage compared to enzyme immunoassay.

  4. Characterization of infectious Murray Valley encephalitis virus derived from a stably cloned genome-length cDNA.

    Science.gov (United States)

    Hurrelbrink, R J; Nestorowicz, A; McMinn, P C

    1999-12-01

    An infectious cDNA clone of Murray Valley encephalitis virus prototype strain 1-51 (MVE-1-51) was constructed by stably inserting genome-length cDNA into the low-copy-number plasmid vector pMC18. Designated pMVE-1-51, the clone consisted of genome-length cDNA of MVE-1-51 under the control of a T7 RNA polymerase promoter. The clone was constructed by using existing components of a cDNA library, in addition to cDNA of the 3' terminus derived by RT-PCR of poly(A)-tailed viral RNA. Upon comparison with other flavivirus sequences, the previously undetermined sequence of the 3' UTR was found to contain elements conserved throughout the genus FLAVIVIRUS: RNA transcribed from pMVE-1-51 and subsequently transfected into BHK-21 cells generated infectious virus. The plaque morphology, replication kinetics and antigenic profile of clone-derived virus (CDV-1-51) was similar to the parental virus in vitro. Furthermore, the virulence properties of CDV-1-51 and MVE-1-51 (LD(50) values and mortality profiles) were found to be identical in vivo in the mouse model. Through site-directed mutagenesis, the infectious clone should serve as a valuable tool for investigating the molecular determinants of virulence in MVE virus.

  5. Treatment of viral encephalitis.

    Science.gov (United States)

    Domingues, Renan Barros

    2009-03-01

    Several viruses may cause central nervous system diseases with a broad range of clinical manifestations. The time course of the viral encephalitis can be acute, subacute, or chronic. Pathologically there are encephalitis with direct viral entry into the CNS in which brain parenchyma exhibits neuronal damaging and viral antigens and there are postinfectious autoimmune encephalitis associated with systemic viral infections with brain tissue presenting perivascular aggregation of immune cells and myelin damaging. Some virus affect previously healthy individuals while others produce encephalitis among imunocompromised ones. Factors such evolving lifestyles and ecological changes have had a considerable impact on the epidemiology of some viral encephalitis [e.g. West-Nile virus, and Japanese B virus]. Citomegalovirus and JC virus are examples of infections of the brain that have been seen more frequently because they occur in immunocompromised patients. In the other hand many scientific achievements in neuroimaging, molecular diagnosis, antiviral therapy, immunomodulatory treatments, and neurointensive care have allowed more precise and earlier diagnoses and more efficient treatments, resulting in improved outcomes. In this article, we will present the current drug options in the management of the main acute and chronic viral infection of the central nervous system of immunocompetent and immunocompromised adults, focusing on drugs mechanisms of action, efficacy, and side effects. The early diagnosis and correct management of such diseases can reduce mortality and neurological sequelae; however, even with recent treatment advances, potentially devastating outcomes are still possible.

  6. The integration of a macrophage-adapted live vaccine strain of equine infectious anaemia virus (EIAV) in the horse genome.

    Science.gov (United States)

    Liu, Qiang; Wang, Xue-Feng; Du, Cheng; Lin, Yue-Zhi; Ma, Jian; Wang, Yu-Hong; Zhou, Jian-Hua; Wang, Xiaojun

    2017-09-07

    Integration is an important feature of retroviruses and retrovirus-based therapeutic transfection vectors. The non-primate lentivirus equine infectious anaemia virus (EIAV) primarily targets macrophages/monocytes in vivo. Investigation of the integration features of EIAVDLV121 strains, which are adapted to donkey monocyte-derived macrophages (MDMs), is of great interest. In this study, we analysed the integration features of EIAVDLV121 in equine MDMs during in vitro infection. Our previously published integration sites (IS) for EIAVFDDV13 in fetal equine dermal (FED) cells were also analysed in parallel as references. Sequencing of the host genomic regions flanking the viral IS showed that reference sequence (RefSeq) genes were preferentially targeted for integration by EIAVDLV121. Introns, AT-rich regions, long interspersed nuclear elements (LINEs) and DNA transposons were also predominantly biased toward viral insertion, which is consistent with EIAVFDDV13 integration into the horse genome in FED cells. In addition, the most significantly enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, specifically gag junctions for EIAVDLV121 and tight junctions for EIAVFDDV13, are regulators of metabolic function, which is consistent with the common bioprocesses, specifically cell cycle and chromosome/DNA organization, identified by gene ontology (GO) analysis. Our results demonstrate that EIAV integration occurs in regions that harbour structural and topological features of local chromatin in both macrophages and fibroblasts. Our data on EIAV will facilitate further understanding of lentivirus infection and the development of safer and more effective gene therapy vectors.

  7. Control of equine infectious anemia virus replication following immune reconstitution in an Arabian foal with severe combined immunodeficiency

    Science.gov (United States)

    Mealey, Robert H.; Fraser, Darrilyn G.; Oaks, J. Lindsay; Cantor, Glenn H.; McGuire, Travis C.

    2012-01-01

    Acute infection with equine infectious anemia virus (EIAV), a lentivirus of horses, results in a persistent high-level viremia in Arabian foals affected with severe combined immunodeficiency (SCID). This observation argues against the idea that the transient nature of acute lentiviral viremia is solely a function of viral population dynamics. To extend these studies, EIAV-specific immune reconstitution was attempted prior to EIAV challenge in 2 SCID foals, using adoptively transferred virus-stimulated lymphocytes derived from persistently EIAV-infected half sibling donors. Following transfer, lymphocyte engraftment occurred in 1 foal, and EIAV-specific cytotoxic T lymphocytes as well as neutralizing antibody activity developed. Following a brief period of plasma viremia in this foal, EIAV replication was controlled and plasma virus could not be detected by RT-PCR or culture. These results provide further direct evidence that a specific immune response is required for termination of plasma viremia in acute lentiviral infections. PMID:11683583

  8. Exploring Genomic, Geographic and Virulence Interactions among Epidemic and Non-Epidemic St. Louis Encephalitis Virus (Flavivirus Strains.

    Directory of Open Access Journals (Sweden)

    Luis A Diaz

    Full Text Available St. Louis encephalitis virus (SLEV is a re-emerging arbovirus in South America. In 2005, an encephalitis outbreak caused by SLEV was reported in Argentina. The reason for the outbreak remains unknown, but may have been related to virological factors, changes in vectors populations, avian amplifying hosts, and/or environmental conditions. The main goal of this study was to characterize the complete genome of epidemic and non-epidemic SLEV strains from Argentina. Seventeen amino acid changes were detected; ten were non-conservative and located in proteins E, NS1, NS3 and NS5. Phylogenetic analysis showed two major clades based on geography: the North America and northern Central America (NAnCA clade and the South America and southern Central America (SAsCA clade. Interestingly, the presence of SAsCA genotype V SLEV strains in the NAnCA clade was reported in California, Florida and Texas, overlapping with known bird migration flyways. This work represents the first step in understanding the molecular mechanisms underlying virulence and biological variation among SLEV strains.

  9. Prevalence of tick-borne encephalitis virus in Ixodes ricinus ticks from three islands in north-western Norway.

    Science.gov (United States)

    Paulsen, Katrine M; Pedersen, Benedikte N; Soleng, Arnulf; Okbaldet, Yohannes B; Pettersson, John H-O; Dudman, Susanne G; Ottesen, Preben; Vik, Inger Sofie Samdal; Vainio, Kirsti; Andreassen, Åshild

    2015-09-01

    Tick-borne encephalitis (TBE) is the most important viral tick-borne disease in Europe and can cause severe disease in humans. In Norway, human cases have been reported only from the southern coast. The aim of this study was to investigate the prevalence of tick-borne encephalitis virus (TBEV) in questing Ixodes ricinus ticks from the north-western part of Norway. A total of 4509 ticks were collected by flagging in May and June 2014. A subpopulation of 2220 nymphs and 162 adult ticks were analysed by real-time PCR and positive samples were confirmed by pyrosequencing. The estimated prevalence of TBEV was 3.08% among adult ticks from Sekken in Møre og Romsdal County and 0.41% among nymphs from both Hitra and Frøya in Sør-Trøndelag County. This study indicates that TBEV might be more widespread than the distribution of reported human cases suggests. © 2015 APMIS. Published by John Wiley & Sons Ltd.

  10. Tick-Borne Encephalitis Virus Habitats in North East Germany: Reemergence of TBEV in Ticks after 15 Years of Inactivity

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    Silvius Frimmel

    2014-01-01

    Full Text Available The incidence of tick-borne encephalitis has risen in Europe since 1990 and the tick-borne encephalitis virus (TBEV has been documented to be spreading into regions where it was not previously endemic. In Mecklenburg-West Pomerania, a federal state in Northern Germany, TBEV was not detectable in over 16,000 collected ticks between 1992 and 2004. Until 2004, the last human case of TBE in the region was reported in 1985. Following the occurrence of three autochthonous human cases of TBE after 2004, however, we collected ticks from the areas in which the infections were contracted. To increase the chance of detecting TBEV-RNA, some of the ticks were fed on mice. Using nested RT-PCR, we were able to confirm the presence of TBEV in ticks for the first time after 15 years. A phylogenetic analysis revealed a close relationship between the sequences we obtained and a TBEV sequence from Mecklenburg-East Pomerania published in 1992 and pointed to the reemergence of a natural focus of TBEV after years of low activity. Our results imply that natural foci of TBEV may either persist at low levels of activity for years or reemerge through the agency of migrating birds.

  11. Reconsidering the classification of tick-borne encephalitis virus within the Siberian subtype gives new insights into its evolutionary history.

    Science.gov (United States)

    Kovalev, S Y; Mukhacheva, T A

    2017-11-01

    Tick-borne encephalitis is widespread in Eurasia and transmitted by Ixodes ticks. Classification of its causative agent, tick-borne encephalitis virus (TBEV), includes three subtypes, namely Far-Eastern, European, and Siberian (TBEV-Sib), as well as a group of 886-84-like strains with uncertain taxonomic status. TBEV-Sib is subdivided into three phylogenetic lineages: Baltic, Asian, and South-Siberian. A reason to reconsider TBEV-Sib classification was the analysis of 186 nucleotide sequences of an E gene fragment submitted to GenBank during the last two years. Within the South-Siberian lineage, we have identified a distinct group with prototype strains Aina and Vasilchenko as an individual lineage named East-Siberian. The analysis of reclassified lineages has promoted a new model of the evolutionary history of TBEV-Sib lineages and TBEV-Sib as a whole. Moreover, we present arguments supporting separation of 886-84-like strains into an individual TBEV subtype, which we propose to name Baikalian (TBEV-Bkl). Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Serological Prevalence Against Japanese Encephalitis Virus-Serocomplex Flaviviruses in Commensal and Field Rodents in South China.

    Science.gov (United States)

    Chen, Shao-Wei; Jiang, Li-Na; Zhong, Xue-Shan; Zheng, Xue-Yan; Ma, Shu-Juan; Xiong, Yi-Quan; Zhou, Jun-Hua; Li, Xing; Ke, Xue-Mei; Zhou, Wen; Chen, Qing

    2016-12-01

    Japanese encephalitis caused by Japanese encephalitis virus (JEV) is an endemic zoonotic disease of high public health importance in the Asian Pacific region. The aim of this study was to investigate the presence of JEV infection in commensal and field rodents in South China. RNA copies of JEV were detected in brain samples of rodents using real-time RT-PCR. Detection of serum against JEV-reactive antibodies was performed using indirect enzyme-linked immunosorbent assay and microneutralization test. In total, 198 rodents were collected from Guangzhou City and Xiamen City between November 2013 and May 2014. JEV RNA was not detected in 188 brain samples. Forty-four in 96 serum samples (45.8%) were positive for JEV-reactive IgG antibodies. The prevalence of neutralizing antibodies to against JEV-reactive in these serum samples was 61.5% (24/39), with titers ranging from 1:10 to 1:56. Rodents are not known to play a role in transmission of JEV in Asia, nor is there an evidence to support a role for rodents in transmission of other related flaviviruses in China. However, in the current study, we detected evidence of JEV-reactive antibodies in large numbers of Rattus norvegicus and Rattus losea Swinhoe. Further studies of rodents as potential hosts of JEV or other related flaviviruses are warranted.

  13. Comparison of argentinean saint louis encephalitis virus non-epidemic and epidemic strain infections in an avian model.

    Directory of Open Access Journals (Sweden)

    Luis Adrián Diaz

    2011-05-01

    Full Text Available St. Louis encephalitis virus (SLEV, Flavivirus, Flaviviridae is an emerging mosquito-borne pathogen in South America, with human SLEV encephalitis cases reported in Argentina and Brazil. Genotype III strains of SLEV were isolated from Culex quinquefasciatus mosquitoes in Cordoba, Argentina in 2005, during the largest SLEV outbreak ever reported in South America. The present study tested the hypothesis that the recent, epidemic SLEV strain exhibits greater virulence in birds as compared with a non-epidemic genotype III strain isolated from mosquitoes in Santa Fe Province 27 years earlier. The observed differences in infection parameters between adult House sparrows (Passer domesticus that were needle-inoculated with either the epidemic or historic SLEV strain were not statistically significant. However, only the House sparrows that were infected with the epidemic strain achieved infectious-level viremia titers sufficient to infect Cx. spp. mosquitoes vectors. Furthermore, the vertebrate reservoir competence index values indicated an approximately 3-fold increase in amplification potential of House sparrows infected with the epidemic strain when pre-existing flavivirus-reactive antibodies were present, suggesting the possibility that antibody-dependent enhancement may increase the risk of avian-amplified transmission of SLEV in South America.

  14. Early detection of tick-borne encephalitis virus spatial distribution and activity in the province of Trento, northern Italy

    Directory of Open Access Journals (Sweden)

    Annapaola Rizzoli

    2007-05-01

    Full Text Available New human cases of tick-borne encephalitis (TBE have recently been recorded outside the recognised foci of this disease, i.e. in the province of Trento in northern Italy. In order to predict the highest risk areas for increased TBE virus activity, we have combined cross-sectional serological data, obtained from 459 domestic goats, with analysis of the autumnal cooling rate based on Moderate Resolution Imaging Spectroradiometer (MODIS land surface temperature (LST data. A significant relationship between finding antibodies against the virus in serum (seroprevalence in goats and the autumnal cooling rate was detected, indicating that the transmission intensity of the virus does not only vary spatially, but also in relation to climatic factors. Virus seroprevalence in goats was correlated with the occurrence of TBE in humans and also with the average number of forestry workers’ tick bites, demonstrating that serological screening of domestic animals, combined with an analysis of the autumnal cooling rate, can be used as early-warning predictors of TBE risk in humans.

  15. Evolution and Divergence of H3N8 Equine Influenza Viruses Circulating in the United Kingdom from 2013 to 2015

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    Adam Rash

    2017-02-01

    Full Text Available Equine influenza viruses (EIV are a major cause of acute respiratory disease in horses worldwide and occasionally also affect vaccinated animals. Like other influenza A viruses, they undergo antigenic drift, highlighting the importance of both surveillance and virus characterisation in order for vaccine strains to be kept up to date. The aim of the work reported here was to monitor the genetic and antigenic changes occurring in EIV circulating in the UK from 2013 to 2015 and to identify any evidence of vaccine breakdown in the field. Virus isolation, reverse transcription polymerase chain reaction (RT-PCR and sequencing were performed on EIV-positive nasopharyngeal swab samples submitted to the Diagnostic Laboratory Services at the Animal Health Trust (AHT. Phylogenetic analyses were completed for the haemagglutinin-1 (HA1 and neuraminidase (NA genes using PhyML and amino acid sequences compared against the current World Organisation for Animal Health (OIE-recommended Florida clade 2 vaccine strain. Substitutions between the new isolates and the vaccine strain were mapped onto the three-dimensional structure protein structures using PyMol. Antigenic analyses were carried out by haemagglutination inhibition assay using a panel of post-infection ferret antisera. Sixty-nine outbreaks of equine influenza in the UK were reported by the AHT between January 2013 and December 2015. Forty-seven viruses were successfully isolated in eggs from 41 of the outbreaks. Only three cases of vaccine breakdown were identified and in each case the vaccine used contained a virus antigen not currently recommended for equine influenza vaccines. Nucleotide sequencing of the HA and NA genes revealed that all of the viruses belonged to the Florida clade 2 sub-lineage of H3N8 EIV. Phylogenetic and sequence analyses showed that the two sub-populations, previously identified within clade 2, continued to circulate and had accrued further amino acid substitutions. Antigenic

  16. Incidence and clinical features of herpes simplex viruses (1 and 2) and varicella-zoster virus infections in an adult Korean population with aseptic meningitis or encephalitis.

    Science.gov (United States)

    Choi, Rihwa; Kim, Gyeong-Moon; Jo, Ik Joon; Sim, Min Seob; Song, Keun Jeong; Kim, Byoung Joon; Na, Duk L; Huh, Hee Jae; Kim, Jong-Won; Ki, Chang-Seok; Lee, Nam Yong

    2014-06-01

    Since there are limited data on the incidence and clinical findings of central nervous system (CNS) infection by three α-herpesviruses including human herpes simplex virus 1 (HSV-1), HSV-2 and varicella-zoster virus (VZV) in Korea, a retrospective analysis of clinical data and polymerase chain reaction (PCR) results was performed in patients who presented with suspicion of acute viral meningitis and/or encephalitis at the emergency department of a tertiary referral hospital in Seoul, Korea. During the 3-year study period, a total of 224 cerebrospinal fluid (CSF) samples from 224 patients were examined. Among the 224 patients, 135 (60.3%) patients were identified as having aseptic meningitis (n = 70, 51.9%), encephalitis (n = 41, 30.4%) or meningoencephalitis (n = 24, 17.8%) at discharge. Twenty-four (17.8%) patients were identified as having VZV meningitis (n = 16, 11.9%), VZV meningoencephalitis (n = 2, 1.5%), HSV-2 meningitis (n = 4, 3.0%), or HSV-1 encephalitis (n = 2, 1.5%). Of the 24 patients infected with the three herpesviruses, immunocompromised patients accounted for 33.3% (n = 8). Skin rashes were observed in half (n = 9) of the patients with VZV, and none with HSV-1 or HSV-2. One patient with VZV meningitis and four patients with brain parenchymal involvement had neurologic sequelae. In conclusion, three herpesviruses are important causative agents of CNS infectious disease with significant morbidity in adults, regardless of the immunologic status. Therefore, CSF should be examined for HSV-1, HSV-2, and VZV using sensitive diagnostic methods in all cases of adult patients with clinical manifestations of CNS disease in order to identify the correct etiology and to determine appropriate therapy. © 2014 Wiley Periodicals, Inc.

  17. Detection and differentiation of Japanese encephalitis virus genotype I and genotype III by reverse transcription loop-mediated isothermal amplification combined with restriction fragment length polymorphism.

    Science.gov (United States)

    Zhang, Liang; Cao, Sanjie; Wu, Rui; Zhu, Shuquan; Liu, Hanyang; Yuan, Lei; Shi, Shuangyan; Zhang, Dan; Huang, Xiaobo; Wen, Xintian; Wen, Yiping; Yan, Qigui; Huang, Yong; Ma, Xiaoping

    2015-04-01

    Japanese encephalitis (JE), which is a mosquito-borne arboviral infection, is the leading cause of viral encephalitis in Asian countries. The causative agent of JE is Japanese encephalitis virus (JEV), in which the predominant genotype has changed from genotype III (G III) to genotype I (G I). However, a method for the rapid differentiation between JEV G I and G III remains unavailable. This study aimed to establish a rapid JEV genotyping method using reverse transcription loop-mediated isothermal amplification (RT-LAMP). An Spe I site, which was located in the target sequence (C gene) of JEV G III strains but not in JEV G I strains, was selected as the RT-LAMP target. After testing 64 specimens, results showed that RT-LAMP can detect and differentiate JEV G I and G III specifically. Thus, a novel RT-LAMP system for the rapid detection and differentiation of JEV G I and G III was developed successfully.

  18. Elaboration of a clinical and paraclinical score to estimate the probability of herpes simplex virus encephalitis in patients with febrile, acute neurologic impairment.

    Science.gov (United States)

    Gennai, S; Rallo, A; Keil, D; Seigneurin, A; Germi, R; Epaulard, O

    2016-06-01

    Herpes simplex virus (HSV) encephalitis is associated with a high risk of mortality and sequelae, and early diagnosis and treatment in the emergency department are necessary. However, most patients present with non-specific febrile, acute neurologic impairment; this may lead clinicians to overlook the diagnosis of HSV encephalitis. We aimed to identify which data collected in the first hours in a medical setting were associated with the diagnosis of HSV encephalitis. We conducted a multicenter retrospective case-control study in four French public hospitals from 2007 to 2013. The cases were the adult patients who received a confirmed diagnosis of HSV encephalitis. The controls were all the patients who attended the emergency department of Grenoble hospital with a febrile acute neurologic impairment, without HSV detection by polymerase chain reaction (PCR) in the cerebrospinal fluid (CSF), in 2012 and 2013. A multivariable logistic model was elaborated to estimate factors significantly associated with HSV encephalitis. Finally, an HSV probability score was derived from the logistic model. We identified 36 cases and 103 controls. Factors independently associated with HSV encephalitis were the absence of past neurological history (odds ratio [OR] 6.25 [95 % confidence interval (CI): 2.22-16.7]), the occurrence of seizure (OR 8.09 [95 % CI: 2.73-23.94]), a systolic blood pressure ≥140 mmHg (OR 5.11 [95 % CI: 1.77-14.77]), and a C-reactive protein <10 mg/L (OR 9.27 [95 % CI: 2.98-28.88]). An HSV probability score was calculated summing the value attributed to each independent factor. HSV encephalitis diagnosis may benefit from the use of this score based upon some easily accessible data. However, diagnostic evocation and probabilistic treatment must remain the rule.

  19. Relationships between infection with caprine arthritis encephalitis virus, intramammary bacterial infection and somatic cell counts in dairy goats.

    Science.gov (United States)

    Sánchez, A; Contreras, A; Corrales, J C; Marco, J C

    2001-06-09

    Somatic cell counts, the bacteriological condition of the milk and antibodies against caprine arthritis encephalitis virus (CAEV) were measured monthly throughout lactation in 121 lactating goats of the Murcia-Granada breed in four commercial dairy goat herds. The prevalence of bacterial intramammary infection was 5.6 per cent and the prevalence of CAEV infection was 20.6 per cent. An analysis of variance revealed a significant effect of herd, intramammary infection and the interaction between intramammary infection and CAEV on the somatic cell count. In udder halves free of intramammary infection, the somatic cell counts were significantly lower in seronegative goats than in seropositive goats (Peffect was not present in the seropositive animals.

  20. MicroRNA-19b-3p Modulates Japanese Encephalitis Virus-Mediated Inflammation via Targeting RNF11.

    Science.gov (United States)

    Ashraf, Usama; Zhu, Bibo; Ye, Jing; Wan, Shengfeng; Nie, Yanru; Chen, Zheng; Cui, Min; Wang, Chong; Duan, Xiaodong; Zhang, Hao; Chen, Huanchun; Cao, Shengbo

    2016-05-01

    Japanese encephalitis virus (JEV) can invade the central nervous system and consequently induce neuroinflammation, which is characterized by profound neuronal cell damage accompanied by astrogliosis and microgliosis. Albeit microRNAs (miRNAs) have emerged as major regulatory noncoding RNAs with profound effects on inflammatory response, it is unknown how astrocytic miRNAs regulate JEV-induced inflammation. Here, we found the involvement of miR-19b-3p in regulating the JEV-induced inflammatory responsein vitroandin vivo The data demonstrated that miR-19b-3p is upregulated in cultured cells and mouse brain tissues during JEV infection. Overexpression of miR-19b-3p led to increased production of inflammatory cytokines, including tumor necrosis factor alpha, interleukin-6, interleukin-1β, and chemokine (C-C motif) ligand 5, after JEV infection, whereas knockdown of miR-19b-3p had completely opposite effects. Mechanistically, miR-19b-3p modulated the JEV-induced inflammatory response via targeting ring finger protein 11, a negative regulator of nuclear factor kappa B signaling. We also found that inhibition of ring finger protein 11 by miR-19b-3p resulted in accumulation of nuclear factor kappa B in the nucleus, which in turn led to higher production of inflammatory cytokines.In vivosilencing of miR-19b-3p by a specific antagomir reinvigorates the expression level of RNF11, which in turn reduces the production of inflammatory cytokines, abrogates gliosis and neuronal cell death, and eventually improves the survival rate in the mouse model. Collectively, our results demonstrate that miR-19b-3p positively regulates the JEV-induced inflammatory response. Thus, miR-19b-3p targeting may constitute a thought-provoking approach to rein in JEV-induced inflammation. Japanese encephalitis virus (JEV) is one of the major causes of acute encephalitis in humans worldwide. The pathological features of JEV-induced encephalitis are inflammatory reactions and neurological diseases

  1. A Feasibility Study of Quantifying Longitudinal Brain Changes in Herpes Simplex Virus (HSV Encephalitis Using Magnetic Resonance Imaging (MRI and Stereology.

    Directory of Open Access Journals (Sweden)

    Sylviane Defres

    Full Text Available To assess whether it is feasible to quantify acute change in temporal lobe volume and total oedema volumes in herpes simplex virus (HSV encephalitis as a preliminary to a trial of corticosteroid therapy.The study analysed serially acquired magnetic resonance images (MRI, of patients with acute HSV encephalitis who had neuroimaging repeated within four weeks of the first scan. We performed volumetric measurements of the left and right temporal lobes and of cerebral oedema visible on T2 weighted Fluid Attenuated Inversion Recovery (FLAIR images using stereology in conjunction with point counting.Temporal lobe volumes increased on average by 1.6% (standard deviation (SD 11% in five patients who had not received corticosteroid therapy and decreased in two patients who had received corticosteroids by 8.5%. FLAIR hyperintensity volumes increased by 9% in patients not receiving treatment with corticosteroids and decreased by 29% in the two patients that had received corticosteroids.This study has shown it is feasible to quantify acute change in temporal lobe and total oedema volumes in HSV encephalitis and suggests a potential resolution of swelling in response to corticosteroid therapy. These techniques could be used as part of a randomized control trial to investigate the efficacy of corticosteroids for treating HSV encephalitis in conjunction with assessing clinical outcomes and could be of potential value in helping to predict the clinical outcomes of patients with HSV encephalitis.

  2. A Feasibility Study of Quantifying Longitudinal Brain Changes in Herpes Simplex Virus (HSV) Encephalitis Using Magnetic Resonance Imaging (MRI) and Stereology.

    Science.gov (United States)

    Defres, Sylviane; Keller, Simon S; Das, Kumar; Vidyasagar, Rishma; Parkes, Laura M; Burnside, Girvan; Griffiths, Michael; Kopelman, Michael; Roberts, Neil; Solomon, Tom

    2017-01-01

    To assess whether it is feasible to quantify acute change in temporal lobe volume and total oedema volumes in herpes simplex virus (HSV) encephalitis as a preliminary to a trial of corticosteroid therapy. The study analysed serially acquired magnetic resonance images (MRI), of patients with acute HSV encephalitis who had neuroimaging repeated within four weeks of the first scan. We performed volumetric measurements of the left and right temporal lobes and of cerebral oedema visible on T2 weighted Fluid Attenuated Inversion Recovery (FLAIR) images using stereology in conjunction with point counting. Temporal lobe volumes increased on average by 1.6% (standard deviation (SD 11%) in five patients who had not received corticosteroid therapy and decreased in two patients who had received corticosteroids by 8.5%. FLAIR hyperintensity volumes increased by 9% in patients not receiving treatment with corticosteroids and decreased by 29% in the two patients that had received corticosteroids. This study has shown it is feasible to quantify acute change in temporal lobe and total oedema volumes in HSV encephalitis and suggests a potential resolution of swelling in response to corticosteroid therapy. These techniques could be used as part of a randomized control trial to investigate the efficacy of corticosteroids for treating HSV encephalitis in conjunction with assessing clinical outcomes and could be of potential value in helping to predict the clinical outcomes of patients with HSV encephalitis.

  3. Specificity and dynamics of effector and memory CD8 T cell responses in human tick-borne encephalitis virus infection.

    Directory of Open Access Journals (Sweden)

    Kim Blom

    2015-01-01

    Full Text Available Tick-borne encephalitis virus (TBEV is transferred to humans by ticks. The virus causes tick-borne encephalitis (TBE with symptoms such as meningitis and meningoencephalitis. About one third of the patients suffer from long-lasting sequelae after clearance of the infection. Studies of the immune response during TBEV-infection are essential to the understanding of host responses to TBEV-infection and for the development of therapeutics. Here, we studied in detail the primary CD8 T cell response to TBEV in patients with acute TBE. Peripheral blood CD8 T cells mounted a considerable response to TBEV-infection as assessed by Ki67 and CD38 co-expression. These activated cells showed a CD45RA-CCR7-CD127- phenotype at day 7 after hospitalization, phenotypically defining them as effector cells. An immunodominant HLA-A2-restricted TBEV epitope was identified and utilized to study the characteristics and temporal dynamics of the antigen-specific response. The functional profile of TBEV-specific CD8 T cells was dominated by variants of mono-functional cells as the effector response matured. Antigen-specific CD8 T cells predominantly displayed a distinct Eomes+Ki67+T-bet+ effector phenotype at the peak of the response, which transitioned to an Eomes-Ki67-T-bet+ phenotype as the infection resolved and memory was established. These transcription factors thus characterize and discriminate stages of the antigen-specific T cell response during acute TBEV-infection. Altogether, CD8 T cells responded strongly to acute TBEV infection and passed through an effector phase, prior to gradual differentiation into memory cells with distinct transcription factor expression-patterns throughout the different phases.

  4. Infection of human endothelial cells by Japanese encephalitis virus: increased expression and release of soluble HLA-E.

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    Shwetank

    Full Text Available Japanese encephalitis virus (JEV is a single stranded RNA virus that infects the central nervous system leading to acute encephalitis in children. Alterations in brain endothelial cells have been shown to precede the entry of this flavivirus into the brain, but infection of endothelial cells by JEV and their consequences are still unclear. Productive JEV infection was established in human endothelial cells leading to IFN-β and TNF-α production. The MHC genes for HLA-A, -B, -C and HLA-E antigens were upregulated in human brain microvascular endothelial cells, the endothelial-like cell line, ECV 304 and human foreskin fibroblasts upon JEV infection. We also report the release/shedding of soluble HLA-E (sHLA-E from JEV infected human endothelial cells for the first time. This shedding of sHLA-E was blocked by an inhibitor of matrix metalloproteinases (MMP. In addition, MMP-9, a known mediator of HLA solubilisation was upregulated by JEV. In contrast, human fibroblasts showed only upregulation of cell-surface HLA-E. Addition of UV inactivated JEV-infected cell culture supernatants stimulated shedding of sHLA-E from uninfected ECV cells indicating a role for soluble factors/cytokines in the shedding process. Antibody mediated neutralization of TNF-α as well as IFNAR receptor together not only resulted in inhibition of sHLA-E shedding from uninfected cells, it also inhibited HLA-E and MMP-9 gene expression in JEV-infected cells. Shedding of sHLA-E was also observed with purified TNF-α and IFN-β as well as the dsRNA analog, poly (I:C. Both IFN-β and TNF-α further potentiated the shedding when added together. The role of soluble MHC antigens in JEV infection is hitherto unknown and therefore needs further investigation.

  5. Full genome sequences and molecular characterization of tick-borne encephalitis virus strains isolated from human patients.

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    Formanová, Petra; Černý, Jiří; Bolfíková, Barbora Černá; Valdés, James J; Kozlova, Irina; Dzhioev, Yuri; Růžek, Daniel

    2015-02-01

    Tick-borne encephalitis virus (TBEV) causes tick-borne encephalitis (TBE), one of the most important human neuroinfections across Eurasia. Up to date, only three full genome sequences of human European TBEV isolates are available, mostly due to difficulties with isolation of the virus from human patients. Here we present full genome characterization of an additional five low-passage TBEV strains isolated from human patients with severe forms of TBE. These strains were isolated in 1953 within Central Bohemia in the former Czechoslovakia, and belong to the historically oldest human TBEV isolates in Europe. We demonstrate here that all analyzed isolates are distantly phylogenetically related, indicating that the emergence of TBE in Central Europe was not caused by one predominant strain, but rather a pool of distantly related TBEV strains. Nucleotide identity between individual sequenced TBEV strains ranged from 97.5% to 99.6% and all strains shared large deletions in the 3' non-coding region, which has been recently suggested to be an important determinant of virulence. The number of unique amino acid substitutions varied from 3 to 9 in individual isolates, but no characteristic amino acid substitution typical exclusively for all human TBEV isolates was identified when compared to the isolates from ticks. We did, however, correlate that the exploration of the TBEV envelope glycoprotein by specific antibodies were in close proximity to these unique amino acid substitutions. Taken together, we report here the largest number of patient-derived European TBEV full genome sequences to date and provide a platform for further studies on evolution of TBEV since the first emergence of human TBE in Europe. Copyright © 2014 Elsevier GmbH. All rights reserved.

  6. The evidence of porcine hemagglutinating encephalomyelitis virus induced nonsuppurative encephalitis as the cause of death in piglets

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    Zi Li

    2016-09-01

    Full Text Available An acute outbreak of porcine hemagglutinating encephalomyelitis virus (PHEV infection in piglets, characterized with neurological symptoms, vomiting, diarrhea, and wasting, occurred in China. Coronavirus-like particles were observed in the homogenized tissue suspensions of the brain of dead piglets by electron microscopy, and a wild PHEV strain was isolated, characterized, and designated as PHEV-CC14. Histopathologic examinations of the dead piglets showed characteristics of non-suppurative encephalitis, and some neurons in the cerebral cortex were degenerated and necrotic, and neuronophagia. Similarly, mice inoculated with PHEV-CC14 were found to have central nervous system (CNS dysfunction, with symptoms of depression, arched waists, standing and vellicating front claws. Furthmore, PHEV-positive labeling of neurons in cortices of dead piglets and infected mice supported the viral infections of the nervous system. Then, the major structural genes of PHEV-CC14 were sequenced and phylogenetically analyzed, and the strain shared 95%–99.2% nt identity with the other PHEV strains available in GenBank. Phylogenetic analysis clearly proved that the wild strain clustered into a subclass with a HEV-JT06 strain. These findings suggested that the virus had a strong tropism for CNS, in this way, inducing nonsuppurative encephalitis as the cause of death in piglets. Simultaneously, the predicted risk of widespread transmission showed a certain variation among the PHEV strains currently circulating around the world. Above all, the information presented in this study can not only provide good reference for the experimental diagnosis of PHEV infection for pig breeding, but also promote its new effective vaccine development.

  7. A Japanese encephalitis virus genotype 5 molecular clone is highly neuropathogenic in a mouse model: impact of the structural protein region on virulence.

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    de Wispelaere, Mélissanne; Frenkiel, Marie-Pascale; Desprès, Philippe

    2015-06-01

    Japanese encephalitis virus (JEV) strains can be separated into 5 genotypes (g1 to g5) based on sequence similarity. JEV g5 strains have been rarely isolated and are poorly characterized. We report here the full characterization of a g5 virus generated using a cDNA-based technology and its comparison with a widely studied g3 strain. We did not observe any major differences between those viruses when their infectious cycles were studied in various cell lines in vitro. Interestingly, the JEV g5 strain was highly pathogenic when inoculated to BALB/c mice, which are known to be largely resistant to JEV g3 infection. The study of chimeric viruses between JEV g3 and g5 showed that there was a poor viral clearance of viruses that express JEV g5 structural proteins in BALB/c mice blood, which correlated with viral invasion of the central nervous system and encephalitis. In addition, using an in vitro model of the blood-brain barrier, we were able to show that JEV g5 does not have an enhanced capacity for entering the central nervous system, compared to JEV g3. Overall, in addition to providing a first characterization of the understudied JEV g5, our work highlights the importance of sustaining an early viremia in the development of JEV encephalitis. Genotype 5 viruses are genetically and serologically distinct from other JEV genotypes and can been associated with human encephalitis, which warrants the need for their characterization. In this study, we characterized the in vitro and in vivo properties of a JEV g5 strain and showed that it was more neuropathogenic in a mouse model than a well-characterized JEV g3 strain. The enhanced virulence of JEV g5 was associated with poor viral clearance but not with enhanced crossing of the blood-brain barrier, thus providing new insights into JEV pathogenesis. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  8. Virus detection in questing ticks is not a sensitive indicator for risk assessment of tick-borne encephalitis in humans.

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    Stefanoff, P; Pfeffer, M; Hellenbrand, W; Rogalska, J; Rühe, F; Makówka, A; Michalik, J; Wodecka, B; Rymaszewska, A; Kiewra, D; Baumann-Popczyk, A; Dobler, G

    2013-05-01

    Tick-borne encephalitis virus (TBEV) is the most important tick-transmitted arbovirus causing human disease in Europe, but information on its endemic occurrence varies between countries because of differences in surveillance systems. Objective data are necessary to ascertain the disease risk for vaccination recommendations and other public health interventions. In two independent, separately planned projects, we used real-time RT-PCR to detect TBE virus in questing ticks. In Poland, 32 sampling sites were selected in 10 administrative districts located in regions where sporadic TBE cases were reported. In Germany, 18 sampling sites were selected in two districts located in a region with high TBE incidence. Altogether, >16,000 ticks were tested by real-time RT-PCR, with no sample testing positive for TBEV. A systematic search for published studies on TBEV prevalence in ticks in Poland and Germany also suggested that testing large numbers of collected ticks could not consistently assure virus detection in known endemic foci. Although assignment of results to administrative regions is essential for TBE risk mapping, this was possible in only 10 (investigating 22,417 ticks) of 15 published studies (>50,000 ticks) identified. We conclude that the collection and screening of ticks by real-time RT-PCR cannot be recommended for assessment of human TBE risk. Alternative methods of environmental TBEV monitoring should be considered, such as serological monitoring of rodents or other wildlife. © 2012 Blackwell Verlag GmbH.

  9. Bispidine-amino acid conjugates act as a novel scaffold for the design of antivirals that block Japanese encephalitis virus replication.

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    V Haridas

    Full Text Available Japanese encephalitis virus (JEV is a major cause of viral encephalitis in South and South-East Asia. Lack of antivirals and non-availability of affordable vaccines in these endemic areas are a major setback in combating JEV and other closely related viruses such as West Nile virus and dengue virus. Protein secondary structure mimetics are excellent candidates for inhibiting the protein-protein interactions and therefore serve as an attractive tool in drug development. We synthesized derivatives containing the backbone of naturally occurring lupin alkaloid, sparteine, which act as protein secondary structure mimetics and show that these compounds exhibit antiviral properties.In this study we have identified 3,7-diazabicyclo[3.3.1]nonane, commonly called bispidine, as a privileged scaffold to synthesize effective antiviral agents. We have synthesized derivatives of bispidine conjugated with amino acids and found that hydrophobic amino acid residues showed antiviral properties against JEV. We identified a tryptophan derivative, Bisp-W, which at 5 µM concentration inhibited JEV infection in neuroblastoma cells by more than 100-fold. Viral inhibition was at a stage post-entry and prior to viral protein translation possibly at viral RNA replication. We show that similar concentration of Bisp-W was capable of inhibiting viral infection of two other encephalitic viruses namely, West Nile virus and Chandipura virus.We have demonstrated that the amino-acid conjugates of 3,7-diazabicyclo[3.3.1]nonane can serve as a molecular scaffold for development of potent antivirals against encephalitic viruses. Our findings will provide a novel platform to develop effective inhibitors of JEV and perhaps other RNA viruses causing encephalitis.

  10. Expression of the hemagglutinin HA1 subunit of the equine influenza virus using a baculovirus expression system.

    Science.gov (United States)

    Sguazza, Guillermo H; Fuentealba, Nadia A; Tizzano, Marco A; Galosi, Cecilia M; Pecoraro, Marcelo R

    2013-01-01

    Equine influenza virus is a leading cause of respiratory disease in horses worldwide. Disease prevention is by vaccination with inactivated whole virus vaccines. Most current influenza vaccines are generated in embryonated hens' eggs. Virions are harvested from allantoic fluid and chemically inactivated. Although this system has served well over the years, the use of eggs as the substrate for vaccine production has several well-recognized disadvantages (cost, egg supply, waste disposal and yield in eggs). The aim of this study was to evaluate a baculovirus system as a potential method for producing recombinant equine influenza hemagglutinin to be used as a vaccine. The hemagglutinin ectodomain (HA1 subunit) was cloned and expressed using a baculovirus expression vector. The expression was determined by SDS-PAGE and immunoblotting. A high yield, 20μg/ml of viral protein, was obtained from recombinant baculovirus-infected cells. The immune response in BALB/c mice was examined following rHA1 inoculation. Preliminary results show that recombinant hemagglutinin expressed from baculovirus elicits a strong antibody response in mice; therefore it could be used as an antigen for subunit vaccines and diagnostic tests. Copyright © 2013 Asociación Argentina de Microbiología. Publicado por Elsevier España. All rights reserved.

  11. Multiplication and distribution of type 2 dengue and Japanese encephalitis viruses in Toxorhynchites splendens after intrathoracic inoculation.

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    Yamamoto, N; Kimura, T; Ohyama, A

    1987-01-01

    The nonhematophagous mosquito Toxorhynchites (Tx.) splendens was found to be the most susceptible to type 2 dengue (D-2) and Japanese encephalitis (JEV) viruses among three hosts examined by virus titration and replication assays. After inoculation with D-2, the number of viral antigen positive cells in the head, thorax and abdomen increased up to day 15 and D-2 reached the maximum titer of 8.4 log10 PFU/g in the head on day 15. Hemocytes were the earliest cell type that could be detected as D-2 antigen positive on day 2. Multiplication of JEV was faster than that of D-2 in the mosquito. The number of JEV antigen positive cells in each part of the mosquito increased up to day 3, JEV reaching the maximum titer of 8.0 log10 PFU/g in the abdomen on day 3. Hemocytes and fat body cells (FBC) could be detected as JEV antigen positive cells on day 1. The time course of D-2 and JEV infection suggested that intrathoracically inoculated viruses were probably initially phagocytosed by hemocytes and/or FBC, and multiplied primarily in their cytoplasm. The infected hemocytes were then transported by the flow of body fluid and viruses were disseminated to other susceptible organs, such as ganglia, salivary glands, etc. The results obtained indicate that the course of infection of D-2 and JEV in Tx. splendens is similar to that in vector mosquitoes. Tx. splendens is therefore very useful for the study of these viruses.

  12. Tick-Borne Encephalitis Virus Replication, Intracellular Trafficking, and Pathogenicity in Human Intestinal Caco-2 Cell Monolayers

    Science.gov (United States)

    Möller, Lars; Schulzke, Joerg D.; Niedrig, Matthias; Bücker, Roland

    2014-01-01

    Tick-borne encephalitis virus (TBEV) is one of the most important vector-borne viruses in Europe and Asia. Its transmission mainly occurs by the bite of an infected tick. However, consuming milk products from infected livestock animals caused TBEV cases. To better understand TBEV transmission via the alimentary route, we studied viral infection of human intestinal epithelial cells. Caco-2 cells were used to investigate pathological effects of TBEV infection. TBEV-infected Caco-2 monolayers showed morphological changes including cytoskeleton rearrangements and cytoplasmic vacuolization. Ultrastructural analysis revealed dilatation of the rough endoplasmic reticulum and further enlargement to TBEV containing caverns. Caco-2 monolayers maintained an intact epithelial barrier with stable transepithelial electrical resistance (TER) during early stage of infection. Concomitantly, viruses were detected in the basolateral medium, implying a transcytosis pathway. When Caco-2 cells were pre-treated with inhibitors of cellular pathways of endocytosis TBEV cell entry was efficiently blocked, suggesting that actin filaments (Cytochalasin) and microtubules (Nocodazole) are important for PI3K-dependent (LY294002) virus endocytosis. Moreover, experimental fluid uptake assay showed increased intracellular accumulation of FITC-dextran containing vesicles. Immunofluorescence microscopy revealed co-localization of TBEV with early endosome antigen-1 (EEA1) as well as with sorting nexin-5 (SNX5), pointing to macropinocytosis as trafficking mechanism. In the late phase of infection, further evidence was found for translocation of virus via the paracellular pathway. Five days after infection TER was slightly decreased. Epithelial barrier integrity was impaired due to increased epithelial apoptosis, leading to passive viral translocation. These findings illuminate pathomechanisms in TBEV infection of human intestinal epithelial cells and viral transmission via the alimentary route. PMID

  13. Tick-borne encephalitis virus replication, intracellular trafficking, and pathogenicity in human intestinal Caco-2 cell monolayers.

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    Chao Yu

    Full Text Available Tick-borne encephalitis virus (TBEV is one of the most important vector-borne viruses in Europe and Asia. Its transmission mainly occurs by the bite of an infected tick. However, consuming milk products from infected livestock animals caused TBEV cases. To better understand TBEV transmission via the alimentary route, we studied viral infection of human intestinal epithelial cells. Caco-2 cells were used to investigate pathological effects of TBEV infection. TBEV-infected Caco-2 monolayers showed morphological changes including cytoskeleton rearrangements and cytoplasmic vacuolization. Ultrastructural analysis revealed dilatation of the rough endoplasmic reticulum and further enlargement to TBEV containing caverns. Caco-2 monolayers maintained an intact epithelial barrier with stable transepithelial electrical resistance (TER during early stage of infection. Concomitantly, viruses were detected in the basolateral medium, implying a transcytosis pathway. When Caco-2 cells were pre-treated with inhibitors of cellular pathways of endocytosis TBEV cell entry was efficiently blocked, suggesting that actin filaments (Cytochalasin and microtubules (Nocodazole are important for PI3K-dependent (LY294002 virus endocytosis. Moreover, experimental fluid uptake assay showed increased intracellular accumulation of FITC-dextran containing vesicles. Immunofluorescence microscopy revealed co-localization of TBEV with early endosome antigen-1 (EEA1 as well as with sorting nexin-5 (SNX5, pointing to macropinocytosis as trafficking mechanism. In the late phase of infection, further evidence was found for translocation of virus via the paracellular pathway. Five days after infection TER was slightly decreased. Epithelial barrier integrity was impaired due to increased epithelial apoptosis, leading to passive viral translocation. These findings illuminate pathomechanisms in TBEV infection of human intestinal epithelial cells and viral transmission via the alimentary

  14. Tick-borne encephalitis virus replication, intracellular trafficking, and pathogenicity in human intestinal Caco-2 cell monolayers.

    Science.gov (United States)

    Yu, Chao; Achazi, Katharina; Möller, Lars; Schulzke, Joerg D; Niedrig, Matthias; Bücker, Roland

    2014-01-01

    Tick-borne encephalitis virus (TBEV) is one of the most important vector-borne viruses in Europe and Asia. Its transmission mainly occurs by the bite of an infected tick. However, consuming milk products from infected livestock animals caused TBEV cases. To better understand TBEV transmission via the alimentary route, we studied viral infection of human intestinal epithelial cells. Caco-2 cells were used to investigate pathological effects of TBEV infection. TBEV-infected Caco-2 monolayers showed morphological changes including cytoskeleton rearrangements and cytoplasmic vacuolization. Ultrastructural analysis revealed dilatation of the rough endoplasmic reticulum and further enlargement to TBEV containing caverns. Caco-2 monolayers maintained an intact epithelial barrier with stable transepithelial electrical resistance (TER) during early stage of infection. Concomitantly, viruses were detected in the basolateral medium, implying a transcytosis pathway. When Caco-2 cells were pre-treated with inhibitors of cellular pathways of endocytosis TBEV cell entry was efficiently blocked, suggesting that actin filaments (Cytochalasin) and microtubules (Nocodazole) are important for PI3K-dependent (LY294002) virus endocytosis. Moreover, experimental fluid uptake assay showed increased intracellular accumulation of FITC-dextran containing vesicles. Immunofluorescence microscopy revealed co-localization of TBEV with early endosome antigen-1 (EEA1) as well as with sorting nexin-5 (SNX5), pointing to macropinocytosis as trafficking mechanism. In the late phase of infection, further evidence was found for translocation of virus via the paracellular pathway. Five days after infection TER was slightly decreased. Epithelial barrier integrity was impaired due to increased epithelial apoptosis, leading to passive viral translocation. These findings illuminate pathomechanisms in TBEV infection of human intestinal epithelial cells and viral transmission via the alimentary route.

  15. The immunogenicity of tetravalent dengue DNA vaccine in mice pre-exposed to Japanese encephalitis or Dengue virus antigens.

    Science.gov (United States)

    Prompetchara, Eakachai; Ketloy, Chutitorn; Keelapang, Poonsook; Sittisombut, Nopporn; Ruxrungtham, Kiat

    2015-09-01

    Asian countries are an endemic area for both dengue (DENV) and Japanese encephalitis viruses (JEV). While JEV vaccines have been used extensively in this region, DENV vaccines remains under development. Whether preexisting naturally acquired or vaccination-induced immunity against JEV may affect the immune response to dengue vaccine candidate is unclear. In this study we used mice previously immunized with JEV vaccines to evaluate the impact on dengue-specific neutralizing antibody responses to a tetravalent dengue DNA vaccine candidate (TDNA). A tetravalent cocktail of plasmids encoding pre-membrane and envelope proteins from each dengue serotype was administered into mice which had been previously primed with inactivated or live-attenuated JEV vaccines, or dengue serotype2 virus (DENV-2). Neutralizing antibody response was measured employing a plaque reduction neutralization test at two weeks after the priming and at four weeks after the second dose of the dengue tetravalent plasmids. Inactivated or live-attenuated JEV vaccines, or DENV-2 induced low levels of neutralizing antibodies against the homologous viruses (JE and dengue virus, respectively). DENV-2 injection induced also low levels of cross-reactive antibodies against DENV-1, -3 and -4. JEV vaccines have no effect on the dengue-specific neutralizing antibody responses to the subsequent TDNA immunization. Pre-exposure to DENV-2 infection increased DENV-2 specific response neutralizing antibody to two doses of TDNA plasmids by six folds, but did not affect antibody response to other serotypes. Priming with JEV vaccines did not impact on dengue virus-specific neutralizing antibody response to a dengue TDNA vaccine candidate in mice.

  16. Kinetics of cytokine profile during intraperitoneal inoculation of Japanese encephalitis virus in BALB/c mice model.

    Science.gov (United States)

    Saxena, Vandana; Mathur, Asha; Krishnani, Narendra; Dhole, Tapan N

    2008-01-01

    Infection with Japanese encephalitis virus (JEV) is mostly asymptomatic/subclinical in 90% of the individuals. Host immune response during subclinical JEV infection is poorly understood. We assessed iNOS, IFN-gamma, TNF-alpha, IL-10 and IL-4 production in spleen, brain and sera of intraperitoneally challenged BALB/c mice by RT-PCR and ELISA along with brain histopathology at different days post inoculation (d.p.i.). In spleen of virus infected mice, expression of all cytokines including iNOS mRNA were upregulated till 5d.p.i. followed by decline. At 5d.p.i., IL-10 expression outcompeted TNF-alpha, IFN-gamma and IL-4. However, in the virus infected mice sera, IL-4 production predominated over TNF-alpha and IL-10 at 5d.p.i. Conversely, cytokines expression and iNOS mRNA remained unchanged in the brain of virus infected mice from 1 to 7d.p.i. A significant increase in the cytokine expression was observed at 11d.p.i. (P<0.05) in virus infected mice brain, with the predominance of IL-10 along with the presence of meningeal inflammation and viral RNA by histology and RT-PCR, respectively. We report a biased pattern of cytokine production in sera, brain and spleen of mice intraperitoneally challenged with JEV. IL-10 exerts neuroprotective function during JEV and regulates deleterious effects of proinflammatory cytokines; however, its mechanism needs further investigation.

  17. Rab5 and Rab11 Are Required for Clathrin-Dependent Endocytosis of Japanese Encephalitis Virus in BHK-21 Cells.

    Science.gov (United States)

    Liu, Chun-Chun; Zhang, Yun-Na; Li, Zhao-Yao; Hou, Jin-Xiu; Zhou, Jing; Kan, Lin; Zhou, Bin; Chen, Pu-Yan

    2017-10-01

    During infection Japanese encephalitis virus (JEV) generally enters host cells via receptor-mediated clathrin-dependent endocytosis. The trafficking of JEV within endosomes is controlled by Rab GTPases, but which Rab proteins are involved in JEV entry into BHK-21 cells is unknown. In this study, entry and postinternalization of JEV were analyzed using biochemical inhibitors, RNA interference, and dominant negative (DN) mutants. Our data demonstrate that JEV entry into BHK-21 cells depends on clathrin, dynamin, and cholesterol but not on caveolae or macropinocytosis. The effect on JEV infection of dominant negative (DN) mutants of four Rab proteins that regulate endosomal trafficking was examined. Expression of DN Rab5 and DN Rab11, but not DN Rab7 and DN Rab9, significantly inhibited JEV replication. These results were further tested by silencing Rab5 or Rab11 expression before viral infection. Confocal microscopy showed that virus particles colocalized with Rab5 or Rab11 within 15 min after virus entry, suggesting that after internalization JEV moves to early and recycling endosomes before the release of the viral genome. Our findings demonstrate the roles of Rab5 and Rab11 on JEV infection of BHK-21 cells through the endocytic pathway, providing new insights into the life cycle of flaviviruses. IMPORTANCE Although Japanese encephalitis virus (JEV) utilizes different endocytic pathways depending on the cell type being infected, the detailed mechanism of its entry into BHK-21 cells is unknown. Understanding the process of JEV endocytosis and postinternalization will advance our knowledge of JEV infection and pathogenesis as well as provide potential novel drug targets for antiviral intervention. With this objective, we used systematic approaches to dissect this process. The results show that entry of JEV into BHK-21 cells requires a low-pH environment and that the process occurs through dynamin-, actin-, and cholesterol-dependent clathrin-mediated endocytosis that

  18. Equine influenza in Brazil

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    Patricia Filippsen Favaro

    2016-06-01

    Full Text Available Equine influenza virus (EIV (H3N8 and H7N7 is the causative agent of equine influenza, or equine flu. The H7N7 subtype has been considered to be extinct worldwide since 1980. Affected animals have respiratory symptoms that can be worsened by secondary bacterial respiratory infection, thereby leading to great economic losses in the horse-breeding industry. In Brazil, equine influenza outbreaks were first reported in 1963 and studies on hemagglutination antibodies against viral subtypes in Brazilian horses have been conducted since then. The objective of the present review was to present the history of the emergence of EIV around the world and in Brazil and the studies that have thus far been developed on EIV in Brazilian equines.

  19. Disease: H00379 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available 533]; Western equine encephalitis [DS:H01534]; Eastern equine encephalitis [DS:H01535]; Australian encephali...Valley encephalitis virus [GN:T40055] (Murray Valley encephalitis / Australian encephalitis) La Crosse virus

  20. Viral encephalitis

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    Marcus Tulius T Silva

    2013-09-01

    Full Text Available While systemic viral infections are exceptionally common, symptomatic viral infections of the brain parenchyma itself are very rare, but a serious neurologic condition. It is estimated that viral encephalitis occurs at a rate of 1.4 cases per 100.000 inhabitants. Geography is a major determinant of encephalitis caused by vector-borne pathogens. A diagnosis of viral encephalitis could be a challenge to the clinician, since almost 70% of viral encephalitis cases are left without an etiologic agent identified. In this review, the most common viral encephalitis will be discussed, with focus on ecology, diagnosis, and clinical management.

  1. Serological evidence of widespread West Nile virus and Japanese encephalitis virus infection in native domestic ducks (Anas platyrhynchos var domesticus) in Kuttanad region, Kerala, India.

    Science.gov (United States)

    Kalaiyarasu, Semmannan; Mishra, Niranjan; Khetan, Rohit Kumar; Singh, Vijendra Pal

    2016-10-01

    Birds can act as reservoirs of West Nile virus (WNV) with a key role in its epidemiology. WNV lineage 1 associated fatal cases of human encephalitis in 2011 and acute flaccid paralysis in 2013 were reported in Alappuzha district, Kerala, India. But no information is available on WNV circulation in domestic ducks, which are abundant, cohabit with humans and occupy wetlands and water bodies in the region. To determine the extent of WNV infection, we investigated 209 sera, 250 oral and 350 cloacal swab samples from local Chara and Chemballi domestic ducks (Anas platyrhynchos var domesticus) in the districts of Alappuzha, Kottayam, Kollam and Pathanamthitta collected during January and March 2015. The serum samples were tested for WNV antibodies first by a competition ELISA and then by a micro virus neutralization test (micro-VNT), while oral and cloacal swabs were subjected to WNV real-time RT-PCR. Ninety five ducks showed evidence of flavivirus antibodies by ELISA. End point neutralizing antibody titre against WNV and Japanese encephalitis virus (JEV) revealed WNV specific antibodies in 24 (11.5%) ducks in 3 districts, JEV specific antibodies in 21 (10%) ducks in 2 districts and flavivirus specific antibodies in 19 (9%) ducks. However, no WNV genomic RNA could be detected. The results of this study demonstrate evidence of widespread WNV and JEV infection in domestic ducks in Kuttanad region, Kerala with a higher seroprevalence to WNV than JEV. Additionally, it highlights the utility of domestic ducks as a surveillance tool to detect WNV/JEV circulation in a region. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Concurrent occurrence of human and equine West Nile virus infections in Central Anatolia, Turkey: the first evidence for circulation of lineage 1 viruses.

    Science.gov (United States)

    Ozkul, Aykut; Ergunay, Koray; Koysuren, Aydan; Alkan, Feray; Arsava, Ethem M; Tezcan, Seda; Emekdas, Gurol; Hacioglu, Sabri; Turan, Mahur; Us, Durdal

    2013-07-01

    West Nile fever is an important zoonotic infection caused by West Nile virus (WNV), a member of the Flaviviridae. Previous serological data from Turkey suggest widespread WNV circulation. This report includes cases of human and equine WNV infections occurring concurrently, and manifesting as central nervous system infections, in two neighboring provinces of Central Anatolia, Turkey. A partial phylogenetic analysis of the causative virus is given for the first time. The cases were reported in February (horses) and March (human). Symptoms of the disease were similar in the two species, characterized by neurological manifestations suggesting meningoencephalitis. Real-time/nested PCRs and commercial immunoassays and a plaque reduction neutralization assay were employed for the detection of viral RNA and specific antibodies, respectively. WNV RNAs were detected in buffy coat (horses) and cerebrospinal fluid (human) samples. Partial nucleotide sequences of the E-gene coding region revealed that the strains are closely related to viruses of lineage 1, clade 1a. Accompanying equine serosurveillance demonstrated WNV-specific antibodies in 31.6% of the samples. This is the first report of acute WNV infections caused by lineage 1 strains from Turkey, in concordance with previous reports from some European and North African countries. Copyright © 2013 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  3. 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

    Directory of Open Access Journals (Sweden)

    Liu Wen-Xin

    2010-09-01

    Full Text Available 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 PrM/M protein, we designed a set of 20 partially overlapping fragments spanning the whole PrM, fused them with GST, and expressed them in an expression vector. Linear epitope M14 (105VNKKEAWLDSTKATRY120 was detected by enzyme-linked immunosorbent assay (ELISA. By removing amino acid residues individually from the carboxy and amino terminal of peptide M14, we confirmed that the minimal unit of the linear epitope of PrM/M was M14-13 (108KEAWLDSTKAT118. This epitope was highly conserved across different JEV strains. Moreover, this epitope did not cross-react with WNV-positive and DENV-positive sera. Conclusion Epitope M14-13 was a JEV specific lineal B-cell epitpe. The results may provide a useful basis for the development of epitope-based virus specific diagnostic clinical techniques.

  4. Tick-borne encephalitis virus, ticks and humans: short-term and long-term dynamics.

    Science.gov (United States)

    Randolph, Sarah E

    2008-10-01

    Much public health concern and scientific interest has been kindled by significant increases in incidence of tick-borne encephalitis over the past 1-2 decades. It is the most important vector-borne disease of humans in Europe, for which excellent long-term data allow robust quantitative analyses. Despite the increasing tendency to attribute all increases in vector-borne diseases to climate change, there is no convincing evidence that the appearance of new foci in Sweden, Switzerland, France and Germany during this century, or the upsurge in cases within well recognized endemic regions, is due to the recorded minor extensions of infectious ticks into higher altitudes and latitudes and into winter periods, in response to warmer conditions. Rather, there is now good evidence of greater human exposure to infected ticks through altered socioeconomic circumstances (in addition to higher densities of tick-feeding deer--not reviewed here), so far best quantified for Central and Eastern Europe. Increased awareness of tick-borne encephalitis and understanding of the changing risk factors, including the role of human behaviour, will ensure better personal protection against infection, including vaccination and avoidance of high-risk activities.

  5. Pigsties near dwellings as a potential risk factor for the prevalence of Japanese encephalitis virus in adult in Shanxi, China.

    Science.gov (United States)

    Ren, Xiaojie; Fu, Shihong; Dai, Peifang; Wang, Huanyu; Li, Yuanyuan; Li, Xiaolong; Lei, Wenwen; Gao, Xiaoyan; He, Ying; Lv, Zhi; Cheng, Jingxia; Wang, Guiqin; Liang, Guodong

    2017-06-08

    The increasing trend of adult cases of Japanese encephalitis (JE) in China, particularly in northern China, has become an important public health issue. We conducted an epidemiological investigation in the south of Shanxi Province to examine the relationships between mosquitoes, Japanese encephalitis virus (JEV), and adult JE cases. Mosquito specimens were collected from the courtyards of farmers' households and pig farms in Shanxi Province. Mosquitoes were pooled, homogenized, and centrifuged. Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect mosquito-borne arbovirus genes in homogenates. Specimens positive for these genes were inoculated into the baby hamster kidney cell line (BHK-21) to isolate virus. Minimum infection rate was calculated and phylogenetic analyses were performed. A total of 7 943 mosquitoes belonging to six species in four genera were collected; Culex tritaeniorhynchus accounted for 73.08% (5 805/7 943), C. pipiens pallens for 24.75% (1 966/7 943), and the remaining 3% (104/ 7943) consisted of Anopheles sinensis, Aedes vexans, Ae. dorsalis, and Armigeres subalbatus. Sixteen pools were positive for JEV based on RT-PCR using JEV pre-membrane gene nested primers. Phylogenetic analyses showed that all JEVs belonged to genotype I; two pools were positive using Getah Virus (GETV) gene primers. In addition, one JEV strain (SXYC1523) was isolated from C. pipiens pallens specimens. These results indicate that the minimum infection rate of JEV in mosquito specimens collected from the courtyards of farmers' households with pigsties was 7.39/1 000; the rate for pig farms was 2.68/1 000; and the rate for farmers' courtyards without pigsties was zero. The high-prevalence regions of adult JE investigated in this study are still the natural epidemic focus of JEV. Having pigsties near dwellings is a potential risk factor contributing to the prevalence of adult JE. To prevent the occurrence of local adult JE cases, a recommendation was

  6. Tissue tropism and molecular characterization of a Japanese encephalitis virus strain isolated from pigs in southwest China.

    Science.gov (United States)

    Yuan, Lei; Wu, Rui; Liu, Hanyang; Wen, Xintian; Huang, Xiaobo; Wen, Yiping; Ma, Xiaoping; Yan, Qigui; Huang, Yong; Zhao, Qin; Cao, Sanjie

    2016-04-02

    Since September 2012, an epidemic has been spreading among swine in a pig farm located in Sichuan province, southwest China, which has resulted in abortion, stillbirth, and fetal mummification. The brains of stillborn pigs were collected and a previously unknown Japanese encephalitis virus (JEV), namely SCYA201201, was isolated. According to the results of agarose gel diffusion precipitation, indirect immunofluorescence analysis, neutralization testing, reverse transcription PCR (RT-PCR) amplification, and physical and chemical testing, the virus was conformed to have the characteristics of JEV. The virus titer in BHK-21 cells was 10(8.47)PFU/ml and the median lethal dose (LD50) to 3-week-old and 7-day-old mice was 1.99 log10 and 1.02 log10 PFU/LD50, respectively. The results of tissue tropism for mice showed that the viral load in the brain was significantly higher than other organs, indicating that the isolate was strongly neurotropic. Additionally, the complete genome sequence of the isolate was determined and compared with other JEV strains. Phylogenetic analysis showed that the isolate belongs to genotype I and may be an imported virus. The isolate had 88.4% nucleotide identity with the Chinese vaccine strain SA14-14-2. However, there were 69 amino acid substitutions compared with the strain SA14-14-2. Some substitutions indicated that SCYA201201 was highly neurovirulent and infective, in accordance with the results of animal testing. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Prevalence of antibodies to Japanese encephalitis virus among inhabitants in Java Island, Indonesia, with a small pig population.

    Science.gov (United States)

    Konishi, Eiji; Sakai, Yohei; Kitai, Yoko; Yamanaka, Atsushi

    2009-05-01

    Japanese encephalitis virus (JEV) is maintained through a transmission cycle between amplifier swine and vector mosquitoes in a peridomestic environment. Thus, studies on natural JEV activities in an environment with a small size of pig population have been limited. Here, we surveyed antibodies against JEV in inhabitants of Jakarta and Surabaya located in Java Island (Indonesia), which has a small swine population. Overall, 2.2% of 1,211 sera collected in Jakarta and 1.8% of 1,751 sera collected in Surabaya had neutralizing antibody titers of >or= 1:160 (90% plaque reduction). All the samples with titers of >or= 1:160 against JEV were also examined for neutralizing antibodies against each of four dengue viruses to confirm that JEV antibody prevalences obtained in the present survey were not attributable to serologic cross-reactivities among flaviviruses distributed in Java. These results indicated that people in Java Island are exposed to natural JEV infections despite a small swine population.

  8. A Review of Methods for Detecting Tick-Borne Encephalitis Virus Infection in Tick, Animal, and Human Specimens.

    Science.gov (United States)

    Ergunay, Koray; Tkachev, Sergey; Kozlova, Irina; Růžek, Daniel

    2016-01-01

    Tick-borne encephalitis virus (TBEV) is the most important tick-transmitted arbovirus causing human disease in Europe and Asia. Over the past decades, the incidence of TBEV infection has significantly increased, with over 13,000 annual hospital referrals in endemic countries and cases emerging in previously unaffected regions. Specific detection of TBEV is required to diagnose suspected human cases or during surveillance of tick vectors and/or susceptible animal species. Widely used techniques for diagnosis comprise serological methods to detect viral antigens or antibodies and nucleic acid tests to detect viral RNA in target specimens. Moreover, virus isolation using susceptible cell lines or vertebrates, electron microscopy, or immunohistochemistry can also be employed on specific occasions. The purpose of this review is to compile and outline various approaches and techniques for detecting TBEV infection in ticks, wild animals, and humans. Specific sections for specimen collection and storage, nucleic acid testing, and serological assays cover various aspects of dynamics, performance characteristics, and utility in the diagnostic workup of suspected cases. Impact of immunoglobulin M testing and quantification, immunoglobulin G avidity, and real-time and quantitative polymerase chain reaction methods were overviewed with assay comparisons. Recent advances in serological assays to mitigate the impact of cross-reactions were further discussed along with the detailed interpretation of laboratory test results in human infections.

  9. Characterization of the GXXXG motif in the first transmembrane segment of Japanese encephalitis virus precursor membrane (prM protein

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    Wu Suh-Chin

    2010-05-01

    Full Text Available Abstract The interaction between prM and E proteins in flavivirus-infected cells is a major driving force for the assembly of flavivirus particles. We used site-directed mutagenesis to study the potential role of the transmembrane domains of the prM proteins of Japanese encephalitis virus (JEV in prM-E heterodimerization as well as subviral particle formation. Alanine insertion scanning mutagenesis within the GXXXG motif in the first transmembrane segment of JEV prM protein affected the prM-E heterodimerization; its specificity was confirmed by replacing the two glycines of the GXXXG motif with alanine, leucine and valine. The GXXXG motif was found to be conserved in the JEV serocomplex viruses but not other flavivirus groups. These mutants with alanine inserted in the two prM transmembrane segments all impaired subviral particle formation in cell cultures. The prM transmembrane domains of JEV may play importation roles in prM-E heterodimerization and viral particle assembly.

  10. Virus-specific regulatory T cells ameliorate encephalitis by repressing effector T cell functions from priming to effector stages.

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    Jingxian Zhao

    2014-08-01

    Full Text Available Several studies have demonstrated the presence of pathogen-specific Foxp3+ CD4 regulatory T cells (Treg in infected animals, but little is known about where and how these cells affect the effector T cell responses and whether they are more suppressive than bulk Treg populations. We recently showed the presence of both epitope M133-specific Tregs (M133 Treg and conventional CD4 T cells (M133 Tconv in the brains of mice with coronavirus-induced encephalitis. Here, we provide new insights into the interactions between pathogenic Tconv and Tregs responding to the same epitope. M133 Tregs inhibited the proliferation but not initial activation of M133 Tconv in draining lymph nodes (DLN. Further, M133 Tregs inhibited migration of M133 Tconv from the DLN. In addition, M133 Tregs diminished microglia activation and decreased the number and function of Tconv in the infected brain. Thus, virus-specific Tregs inhibited pathogenic CD4 T cell responses during priming and effector stages, particularly those recognizing cognate antigen, and decreased mortality and morbidity without affecting virus clearance. These cells are more suppressive than bulk Tregs and provide a targeted approach to ameliorating immunopathological disease in infectious settings.

  11. Development of electrochemical immunosensors based on different serum antibody immobilization methods for detection of Japanese encephalitis virus

    Science.gov (United States)

    Tran, Quang Huy; Hanh Nguyen, Thi Hong; Mai, Anh Tuan; Thuy Nguyen, Thi; Khue Vu, Quang; Nga Phan, Thi

    2012-03-01

    This paper describes the development of electrochemical immunosensors based on human serum antibodies with different immobilization methods for detection of Japanese encephalitis virus (JEV). Human serum containing anti-JEV antibodies was used to immobilize onto the surface of silanized interdigitated electrodes by four methods: direct adsorption (APTES-serum), covalent binding with a cross linker of glutaraldehyde (APTES-GA-serum), covalent binding with a cross linker of glutaraldehyde combined with anti-human IgG (APTES-GA-anti-HIgG-serum) and covalent binding with a cross linker of glutaraldehyde combined with a bioaffinity of protein A (APTES-GA-PrA-serum). Atomic force microscopy was used to verify surface characteristics of the interdigitated electrodes before and after treatment with serum antibodies. The output signal of the immunosensors was measured by the change of conductivity resulting from the specific binding of JEV antigens and serum antibodies immobilized on the electrodes, with the help of horseradish peroxidase (HRP)-labeled secondary antibody against JEV. The results showed that the APTES-GA-PrA-serum method provided the highest signal of the electrochemical immunosensor for detection of JEV antigens, with the linear range from 25 ng ml-1 to 1 μg ml-1, and the limit of detection was about 10 ng ml-1. This study shows a potential development of novel electrochemical immunosensors applied for virus detection in clinical samples in case of possible outbreaks.

  12. OAS1 polymorphisms are associated with susceptibility to West Nile encephalitis in horses.

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    Jonathan J Rios

    Full Text Available West Nile virus, first identified within the United States in 1999, has since spread across the continental states and infected birds, humans and domestic animals, resulting in numerous deaths. Previous studies in mice identified the Oas1b gene, a member of the OAS/RNASEL innate immune system, as a determining factor for resistance to West Nile virus (WNV infection. A recent case-control association study described mutations of human OAS1 associated with clinical susceptibility to WNV infection. Similar studies in horses, a particularly susceptible species, have been lacking, in part, because of the difficulty in collecting populations sufficiently homogenous in their infection and disease states. The equine OAS gene cluster most closely resembles the human cluster, with single copies of OAS1, OAS3 and OAS2 in the same orientation. With naturally occurring susceptible and resistant sub-populations to lethal West Nile encephalitis, we undertook a case-control association study to investigate whether, similar to humans (OAS1 and mice (Oas1b, equine OAS1 plays a role in resistance to severe WNV infection. We identified naturally occurring single nucleotide mutations in equine (Equus caballus OAS1 and RNASEL genes and, using Fisher's Exact test, we provide evidence that mutations in equine OAS1 contribute to host susceptibility. Virtually all of the associated OAS1 polymorphisms were located within the interferon-inducible promoter, suggesting that differences in OAS1 gene expression may determine the host's ability to resist clinical manifestations associated with WNV infection.

  13. Infection dynamics of western equine encephalomyelitis virus (Togaviridae: Alphavirus in four strains of Culex tarsalis (Diptera: Culicidae: an immunocytochemical study

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    Neira Oviedo MV

    2011-04-01

    Full Text Available Marco V Neira Oviedo1,2, William S Romoser1, Calvin BL James1, Farida Mahmood3, William K Reisen31Tropical Disease Institute, Department of Biomedical Sciences, College of Osteopathic Medicine, Ohio University, Athens, OH, USA; 2Oxitec Inc, Oxford, England; 3Center for Vectorborne Diseases, School of Veterinary Medicine, University of California, Davis, CA, USABackground: Vector competence describes the efficiency with which vector arthropods become infected with and transmit pathogens and depends on interactions between pathogen and arthropod genetics as well as environmental factors. For arbovirus transmission, the female mosquito ingests viremic blood, the virus infects and replicates in midgut cells, escapes from the midgut, and disseminates to other tissues, including the salivary glands. Virus-laden saliva is then injected into a new host. For transmission to occur, the virus must overcome several "barriers", including barriers to midgut infection and/or escape and salivary infection and/or escape. By examining the spatial/temporal infection dynamics of Culex tarsalis strains infected with western equine encephalomyelitis virus (WEEV, we identified tissue tropisms and potential tissue barriers, and evaluated the effects of viral dose and time postingestion.Methods: Using immuno-stained paraffin sections, WEEV antigens were tracked in four Cx. tarsalis strains: two recently colonized California field strains – Coachella Valley, Riverside County (COAV and Kern National Wildlife Refuge (KNWR; and two laboratory strains selected for WEEV susceptibility (high viremia producer, HVP, and WEEV resistance (WR.Results and conclusions: Tissues susceptible to WEEV infection included midgut epithelium, neural ganglia, trachea, chorionated eggs, and salivary glands. Neuroendocrine cells in the retrocerebral complex were occasionally infected, indicating the potential for behavioral effects. The HVP and COAV strains vigorously supported viral growth

  14. Cross-reactivity of human monoclonal antibodies generated with peripheral blood lymphocytes from dengue patients with Japanese encephalitis virus

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    Pipattanaboon C

    2013-08-01

    Full Text Available Chonlatip Pipattanaboon,1,3,8,* Tadahiro Sasaki,2,8,* Mitsuhiro Nishimura,2,8 Chayanee Setthapramote,1,8 Pannamthip Pitaksajjakul,1,4,8 Pornsawan Leaungwutiwong,1,3,8 Kriengsak Limkittikul,5,8 Orapim Puiprom,6 Mikiko Sasayama,6 Panjaporn Chaichana,6 Tamaki Okabayashi,6 Takeshi Kurosu,2,8 Ken-ichiro Ono,7,8 Pongrama Ramasoota,1,4,8 Kazuyoshi Ikuta2,8 1Center of Excellence for Antibody Research, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand; 2Department of Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan; 3Department of Microbiology and Immunology, 4Department of Social and Environmental Medicine, 5Department of Tropical Pediatrics, Faculty of Tropical Medicine, Mahidol University, 6Mahidol-Osaka Center for Infectious Diseases, Bangkok, Thailand; 7Medical and Biological Laboratories Corporation Ltd, Nagano, Japan; 8JST/JICA, Science and Technology Research Partnership for Sustainable Development, Tokyo, Japan *These authors made an equal contribution to this study Background: Hybridomas that produce human monoclonal antibodies (HuMAbs against Dengue virus (DV had been prepared previously using peripheral blood lymphocytes from patients with DV during the acute and convalescent phases of a secondary infection. Anti-DV envelope glycoprotein (E 99 clones, anti-DV premembrane protein (prM 8 clones, and anti-DV nonstructural protein 1 (NS1 4 clones were derived from four acute-phase patients, and anti-DV E 2 clones, anti-DV prM 2 clones, and anti-DV NS1 8 clones were derived from five convalescent-phase patients. Methods and results: In the present study, we examined whether these clones cross-reacted with Japanese encephalitis virus (JEV, which belongs to the same virus family. Forty-six of the above-described 99 (46/99 anti-E, 0/8 anti-prM, and 2/4 anti-NS1 HuMAbs from acute-phase, and 0/2 anti-E, 0/2 anti-prM, and 5/8 anti-NS1 HuMAbs from convalescent-phase showed neutralizing activity against

  15. Herpes simplex virus encephalitis in a patient with complete TLR3 deficiency: TLR3 is otherwise redundant in protective immunity

    Science.gov (United States)

    Guo, Yiqi; Audry, Magali; Ciancanelli, Michael; Alsina, Laia; Azevedo, Joana; Herman, Melina; Anguiano, Esperanza; Sancho-Shimizu, Vanessa; Lorenzo, Lazaro; Pauwels, Elodie; Philippe, Paul Bastard; Pérez de Diego, Rebeca; Cardon, Annabelle; Vogt, Guillaume; Picard, Capucine; Andrianirina, Zafitsara Zo; Rozenberg, Flore; Lebon, Pierre; Plancoulaine, Sabine; Tardieu, Marc; Valérie Doireau; Jouanguy, Emmanuelle; Chaussabel, Damien; Geissmann, Frederic; Abel, Laurent

    2011-01-01

    Autosomal dominant TLR3 deficiency has been identified as a genetic etiology of childhood herpes simplex virus 1 (HSV-1) encephalitis (HSE). This defect is partial, as it results in impaired, but not abolished induction of IFN-β and -λ in fibroblasts in response to TLR3 stimulation. The apparently normal resistance of these patients to other infections, viral illnesses in particular, may thus result from residual TLR3 responses. We report here an autosomal recessive form of complete TLR3 deficiency in a young man who developed HSE in childhood but remained normally resistant to other infections. This patient is compound heterozygous for two loss-of-function TLR3 alleles, resulting in an absence of response to TLR3 activation by polyinosinic-polycytidylic acid (poly(I:C)) and related agonists in his fibroblasts. Moreover, upon infection of the patient’s fibroblasts with HSV-1, the impairment of IFN-β and -λ production resulted in high levels of viral replication and cell death. In contrast, the patient’s peripheral blood mononuclear cells responded normally to poly(I:C) and to all viruses tested, including HSV-1. Consistently, various TLR3-deficient leukocytes from the patient, including CD14+ and/or CD16+ monocytes, plasmacytoid dendritic cells, and in vitro derived monocyte-derived macrophages, responded normally to both poly(I:C) and HSV-1, with the induction of antiviral IFN production. These findings identify a new genetic etiology for childhood HSE, indicating that TLR3-mediated immunity is essential for protective immunity to HSV-1 in the central nervous system (CNS) during primary infection in childhood, in at least some patients. They also indicate that human TLR3 is largely redundant for responses to double-stranded RNA and HSV-1 in various leukocytes, probably accounting for the redundancy of TLR3 for host defense against viruses, including HSV-1, outside the CNS. PMID:21911422

  16. Southernmost Asia Is the Source of Japanese Encephalitis Virus (Genotype 1) Diversity from which the Viruses Disperse and Evolve throughout Asia

    Science.gov (United States)

    Wang, Huanyu; Fu, Shihong; Guo, Zhenyang; Liang, Guodong

    2013-01-01

    Background Although a previous study predicted that Japanese encephalitis virus (JEV) originated in the Malaysia/Indonesia region, the virus is known to circulate mainly on the Asian continent. However, there are no reported systematic studies that adequately define how JEV then dispersed throughout Asia. Methodology/Principal Findings In order to understand the mode of JEV dispersal throughout the entire Asian continent and the factors that determine the dispersal characteristics of JEV, a phylogenetic analysis using Bayesian Markov chain Monte Carlo simulations was conducted on all available JEV E gene sequences in GenBank, plus strains recently isolated in China. Here we demonstrate for the first time that JEV lineages can be divided into four endemic cycles, comprising southern Asia, eastern coastal Asia, western Asia, and central Asia. The isolation places of the viruses in each endemic cycle were geographically independent regardless of years, vectors, and hosts of isolation. Following further analysis, we propose that the southernmost region (Thailand, Vietnam, and Yunnan Province, China) was the source of JEV transmission to the Asian continent following its emergence. Three independent transmission routes from the south to north appear to define subsequent dispersal of JEV. Analysis of JEV population dynamics further supports these concepts. Conclusions/Significance These results and their interpretation provide new insights into our understanding of JEV evolution and dispersal and highlight its potential for introduction into non-endemic areas. PMID:24069502

  17. Phylogenetic and molecular characterization of equine H3N8 influenza viruses from Greece (2003 and 2007: Evidence for reassortment between evolutionary lineages

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    Kanellos Theo

    2011-07-01

    Full Text Available Abstract Background For first time in Greece equine influenza virus infection was confirmed, by isolation and molecular analysis, as the cause of clinical respiratory disease among unvaccinated horses during 2003 and 2007 outbreaks. Methods Equine influenza virus (EIV H3N8 was isolated in MDCK cells from 30 nasal swabs from horses with acute respiratory disease, which were tested positive by Directigen Flu A. Isolation was confirmed by haemagglutination assay and RT-PCR assay of the M, HA and NA gene. Results HA sequences of the Greek isolates appeared to be more closely related to viruses isolated in early 1990s in Europe. These results suggested that viruses with fewer changes than those on the main evolutionary lineage may continue to circulate. On the other hand, analysis of deduced NA amino acid sequences were more closely related to viruses isolated in outbreaks in Europe and Asia during 2003-2007. Phylogenetic analysis characterized the Greek isolates as a member of the Eurasian lineage by the haemagglutinin (HA protein alignment, but appeared to be a member of the Florida sublineage clade 2 by the neuraminidase (NA protein sequence suggesting that reassortment might be a possible explanation. Conclusion Our findings suggest that the Greek strains represent an example of "frozen evolution" and probably reassortment between genetically distinct co-circulated strains. Therefore expanding current equine influenza surveillance efforts is a necessity.

  18. Human Transcriptome Response to Immunization with Live- Attenuated Venezuelan equine encephalitis Virus Vaccine (TC 83): Analysis of Whole Blood

    Science.gov (United States)

    2016-11-21

    bacteria, the RIG1-like receptors as part of a classical innate 179 antiviral immune response (i.e., the inflammasome), and the IL-6 signaling pathway. The...indicative of a 293 traditional innate antiviral immune response. There is an extensive overlap between the 294 molecules that exhibit changes in...Early induction of the broad-spectrum innate inflammasome response was noted as a 303 consequence of immunization , spanning days 2 through 7

  19. Directed Molecular Evolution Improves the Immunogenicity and Protective Efficacy of a Venezuelan Equine Encephalitis Virus DNA Vaccine

    Science.gov (United States)

    2009-05-01

    Rapid evolution of a protein in vitro by DNA shuffling. Nature 1994;370(6488):389–91. 15] Locher CP, Soong NW, Whalen RG, Punnonen J. Development of...novel vac- cines using DNA shuffling and screening strategies. Curr Opin Mol Ther 2004;6(1):34–9. 16] Whalen RG, Kaiwar R, Soong NW, Punnonen J. DNA

  20. Effect of eastern equine encephalomyelitis virus on the survival of Aedes albopictus, Anopheles quadrimaculatus, and Coquillettidia perturbans (Diptera: Culicidae).

    Science.gov (United States)

    Moncayo, A C; Edman, J D; Turell, M J

    2000-09-01

    The effect of eastern equine encephalomyelitis (EEE) virus on the survivorship of Aedes albopictus (Skuse), Anopheles quadrimaculatus Say, and Coquillettidia perturbans (Walker) was determined experimentally. Female mosquitoes were allowed to feed on EEE viremic chicks, and survival rates were compared for infected and uninfected mosquitoes. Additionally, the survival of female Cq. perturbans and An. quadrimaculatus intrathoracically (i.t.) inoculated with EEE was compared with controls receiving diluent inoculations. Infection with EEE significantly reduced survival in Cq. perturbans compared with uninfected individuals in per os infection experiments. I.t. infections of Cq. perturbans did not reduce survival when compared with diluent inoculated groups. In contrast, infection with EEE did not affect the survival of Ae. albopictus after per os infection or An. quadrimaculatus after either i.t. or per os infections.

  1. Tick-borne encephalitis.

    Science.gov (United States)

    Lindquist, Lars; Vapalahti, Olli

    2008-05-31

    We review the epidemiological and clinical characteristics of tick-borne encephalitis, and summarise biological and virological aspects that are important for understanding the life-cycle and transmission of the virus. Tick-borne encephalitis virus is a flavivirus that is transmitted by Ixodes spp ticks in a vast area from western Europe to the eastern coast of Japan. Tick-borne encephalitis causes acute meningoencephalitis with or without myelitis. Morbidity is age dependent, and is highest in adults of whom half develop encephalitis. A third of patients have longlasting sequelae, frequently with cognitive dysfunction and substantial impairment in quality of life. The disease arises in patchy endemic foci in Europe, with climatic and ecological conditions suitable for circulation of the virus. Climate change and leisure habits expose more people to tick-bites and have contributed to the increase in number of cases despite availability of effective vaccines. The serological diagnosis is usually straightforward. No specific treatment for the disease exists, and immunisation is the main preventive measure.

  2. The occurrence of Ixodes ricinus ticks and important tick-borne pathogens in areas with high tick-borne encephalitis prevalence in different altitudinal levels of the Czech Republic Part I. Ixodes ricinus ticks and tick-borne encephalitis virus.

    Science.gov (United States)

    Daniel, M; Danielová, V; Kříž, B; Růžek, D; Fialová, A; Malý, M; Materna, J; Pejčoch, M; Erhart, J

    The aim of the three-year study (2011-2013) was to monitor population density of Ixodes ricinus ticks and its infection rate with the tick-borne encephalitis virus in areas with a high incidence of tick-borne encephalitis as reported in the previous decade 2001-2010. Such a comprehensive and long-term study based on existing epidemiolo-gical findings has not previously been conducted in Europe. In the areas of the Ústí nad Labem Region, Olomouc Region, South Bohemian Region, and Highlands Region, 600 m2 plots were selected in the local optimal I. ricinus habitats where tick flagging was performed every year in the spring-summer and autumn seasons of the questing activity. In total, 18,721 I. ricinus ticks (1448 females, 1425 males, and 15,848 nymphs) were collected and investigated. The results have shown that the differences in the infection rate of I. ricinus observed between regions are driven by variation in the density of the local I. ricinus populations which is influenced by the characteris-tics of the whole local biocenosis. The overall prevalence estimate of TBE virus in Ixodes ricinus ticks at the altitudes below 600 m a.s.l. was 0.096 % (95% CI 0.055-0.156) for nymphs, and 0.477 % (95% CI 0.272-0.773) for adults. The dynamics of the seasonal variation in I. ricinus populations, depending primarily on the climatic factors, are behind the interyear differences in the infection rate of ticks and, consequently, in the epidemiological situation of tick-borne encephalitis. The nymph to adult ratio was 5.5 on average but showed great interregional variability (from 10.3 in the Ústí nad Labem Region to 1.8 in the Highlands Region). It might be used in the future as one of the indicators of the composition of the local I. ricinus population and of the level of the circulation of tick-borne pathogens in zoonotic sphere and also for use in the health risk assessment in a given area. Despite the permanent expansion of ticks and tick-borne pathogens in higher

  3. N-methylisatin-beta-thiosemicarbazone derivative (SCH 16) is an inhibitor of Japanese encephalitis virus infection in vitro and in vivo

    Science.gov (United States)

    Sebastian, Liba; Desai, Anita; Shampur, Madhusudana N; Perumal, Yogeeswari; Sriram, D; Vasanthapuram, Ravi

    2008-01-01

    Background During the early and mid part of 20th century, several reports described the therapeutic effects of N-methylisatin-β-Thiosemicarbazone (MIBT) against pox viruses, Maloney leukemia viruses and recently against HIV. However, their ability to inhibit flavivirus replication has not been investigated. Hence the present study was designed to evaluate the antiviral activity of 14 MIBT derivatives against Flaviviruses that are prevalent in India such as Japanese Encephalitis Virus (JEV), Dengue-2 (Den-2) and West Nile viruses (WNV). Results Amongst the fourteen Mannich bases of MIBT derivatives tested one compound – SCH 16 was able to completely inhibit in vitro Japanese encephalitis virus (JEV) and West Nile virus (WNV) replication. However no antiviral activity of SCH 16 was noted against Den-2 virus replication. This compound was able to inhibit 50% of the plaques (IC50) produced by JEV and WNV at a concentration of 16 μgm/ml (0.000025 μM) and 4 μgm/ml (0.000006 μM) respectively. Furthermore, SCH 16 at a concentration of 500 mg/kg body weight administered by oral route twice daily was able to completely (100%) prevent mortality in mice challenged with 50LD50 JEV by the peripheral route. Our experiments to understand the mechanism of action suggest that SCH 16 inhibited JEV replication at the level of early protein translation. Conclusion Only one of the 14 isatin derivatives -SCH 16 exhibited antiviral action on JEV and WNV virus infection in vitro. SCH 16 was also found to completely inhibit JEV replication in vivo in a mouse model challenged peripherally with 50LD50 of the virus. These results warrant further research and development on SCH 16 as a possible therapeutic agent. PMID:18498627

  4. N-methylisatin-beta-thiosemicarbazone derivative (SCH 16 is an inhibitor of Japanese encephalitis virus infection in vitro and in vivo

    Directory of Open Access Journals (Sweden)

    Sriram D

    2008-05-01

    Full Text Available Abstract Background During the early and mid part of 20th century, several reports described the therapeutic effects of N-methylisatin-β-Thiosemicarbazone (MIBT against pox viruses, Maloney leukemia viruses and recently against HIV. However, their ability to inhibit flavivirus replication has not been investigated. Hence the present study was designed to evaluate the antiviral activity of 14 MIBT derivatives against Flaviviruses that are prevalent in India such as Japanese Encephalitis Virus (JEV, Dengue-2 (Den-2 and West Nile viruses (WNV. Results Amongst the fourteen Mannich bases of MIBT derivatives tested one compound – SCH 16 was able to completely inhibit in vitro Japanese encephalitis virus (JEV and West Nile virus (WNV replication. However no antiviral activity of SCH 16 was noted against Den-2 virus replication. This compound was able to inhibit 50% of the plaques (IC50 produced by JEV and WNV at a concentration of 16 μgm/ml (0.000025 μM and 4 μgm/ml (0.000006 μM respectively. Furthermore, SCH 16 at a concentration of 500 mg/kg body weight administered by oral route twice daily was able to completely (100% prevent mortality in mice challenged with 50LD50 JEV by the peripheral route. Our experiments to understand the mechanism of action suggest that SCH 16 inhibited JEV replication at the level of early protein translation. Conclusion Only one of the 14 isatin derivatives -SCH 16 exhibited antiviral action on JEV and WNV virus infection in vitro. SCH 16 was also found to completely inhibit JEV replication in vivo in a mouse model challenged peripherally with 50LD50 of the virus. These results warrant further research and development on SCH 16 as a possible therapeutic agent.

  5. Herpes-simplex virus encephalitis is characterized by an early MMP-9 increase and collagen type IV degradation.

    Science.gov (United States)

    Sellner, Johann; Simon, Franziska; Meyding-Lamade, Uta; Leib, Stephen L

    2006-12-13

    Cerebrovascular complications including cerebral edema, raised intracranial pressure and hemorrhage contribute to the high mortality and morbidity of herpes-simplex virus encephalitis (HSE). We examined changes of collagen type IV, the major constituent of the neurovascular matrix, together with expression and localization of matrix-degrading enzymes during the development of acute HSE. In an experimental model of focal HSE, we found that early, symptomatic HSE (3 days after infection) and acute, fully developed HSE (7 days after infection) are associated with significantly raised levels of matrix-metalloproteinase-9 (MMP-9) (both PHSE and further expanded towards the perivascular space and adjacent tissue in acute HSE. Around the cerebral vasculature, we observed that MMP-9 activity was insufficiently counterbalanced by its endogenous tissue inhibitor of MMP (TIMP) TIMP-1, resulting in loss of collagen type IV. Our findings suggest that MMP-9 is involved in the evolution of HSE by causing damage to the cerebral vasculature. The degradation of the neurovascular matrix in HSE facilitates the development of cerebrovascular complications and may represent a target for novel adjuvant treatment strategies.

  6. Sustained Elevation of Kynurenic Acid in the Cerebrospinal Fluid of Patients with Herpes Simplex Virus Type 1 Encephalitis

    Directory of Open Access Journals (Sweden)

    Ann Atlas

    2013-01-01

    Full Text Available Herpes simplex virus (HSV type 1 encephalitis (HSE is a viral infectious disease with commonly occurring neurodegeneration and neurological/cognitive long-term sequelae. Kynurenic acid (KYNA is a neuroactive tryptophan metabolite, which is elevated in the cerebrospinal fluid (CSF during viral infection as a result of immune activation. The aim of the study was to investigate the role of endogenous brain KYNA for the long-term outcome of the disease. CSF KYNA concentration was analyzed in 25 HSE patients along the course of the disease and compared with that of 25 age-matched healthy volunteers. Within 3 weeks of admission CSF KYNA of HSE patients was markedly elevated (median 33.6 nM compared to healthy volunteers (median 1.45 nM. Following a decline observed after 1–2 months, levels of CSF KYNA were elevated more than 1 year after admission (median 3.4 nM range: 1–9 years. A negative correlation was found between initial CSF KYNA concentrations and severity of the long-term sequelae. This study show a marked elevation in CSF KYNA from patients with HSE, most pronounced during the acute phase of the disease and slowly declining along the recovery. We propose that brain KYNA might potentially protect against neurodegeneration while causing a long-lasting loss in cognitive function associated with the disease.

  7. Blood and milk polymorphonuclear leukocyte and monocyte/macrophage functions in naturally caprine arthritis encephalitis virus infection in dairy goats.

    Science.gov (United States)

    Santos, Bruna Parapinski; Souza, Fernando Nogueira; Blagitz, Maiara Garcia; Batista, Camila Freitas; Bertagnon, Heloísa Godoi; Diniz, Soraia Araújo; Silva, Marcos Xavier; Haddad, João Paulo Amaral; Della Libera, Alice Maria Melville Paiva

    2017-06-01

    The exact influence of caprine arthritis encephalitis virus (CAEV) infection on blood and milk polymorphonuclear leukocytes (PMNLs) and monocyte/macrophages of goats remains unclear. Thus, the present study sought to explore the blood and milk PMNL and monocyte/macrophage functions in naturally CAEV-infected goats. The present study used 18 healthy Saanen goats that were segregated according to sera test outcomes into serologically CAEV negative (n=8; 14 halves) and positive (n=10; 14 halves) groups. All milk samples from mammary halves with milk bacteriologically positive outcomes, somatic cell count ≥2×106cellsmL-1, and abnormal secretions in the strip cup test were excluded. We evaluated the percentage of blood and milk PMNLs and monocyte/macrophages, the viability of PMNLs and monocyte/macrophages, the levels of intracellular reactive oxygen species (ROS) and the nonopsonized phagocytosis of Staphylococcus aureus and Escherichia coli by flow cytometry. In the present study, a higher percentage of milk macrophages (CD14+) and milk polymorphonuclear leukocytes undergoing late apoptosis or necrosis (Annexin-V+/Propidium iodide+) was observed in CAEV-infected goats; we did not find any further alterations in blood and milk PMNL and monocyte/macrophage functions. Thus, regarding our results, the goats naturally infected with CAEV did not reveal pronounced dysfunctions in blood and milk polymorphonuclear leukocytes and monocytes/macrophages. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Characterization of immune responses induced by inactivated, live attenuated and DNA vaccines against Japanese encephalitis virus in mice.

    Science.gov (United States)

    Li, Jieqiong; Chen, Hui; Wu, Na; Fan, Dongying; Liang, Guodong; Gao, Na; An, Jing

    2013-08-28

    Vaccination is the most effective countermeasure for protecting individuals from Japanese encephalitis virus (JEV) infection. There are two types of JEV vaccines currently used in China: the Vero cell-derived inactivated vaccine and the live attenuated vaccine. In this study, we characterized the immune response and protective efficacy induced in mice by the inactivated vaccine, live attenuated vaccine and the DNA vaccine candidate pCAG-JME, which expresses JEV prM-E proteins. We found that the live attenuated vaccine conferred 100% protection and resulted in the generation of high levels of specific anti-JEV antibodies and cytokines. The pCAG-JME vaccine induced protective immunity as well as the live attenuated vaccine. Unexpectedly, immunization with the inactivated vaccine only induced a limited immune response and partial protection, which may be due to the decreased activity of dendritic cells and the expansion of CD4+CD25+Foxp3+ regulatory T cells observed in these mice. Altogether, our results suggest that the live attenuated vaccine is more effective in providing protection against JEV infection than the inactivated vaccine and that pCAG-JME will be a potential JEV vaccine candidate. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Zika Virus-Associated Neurological Disease in the Adult: Guillain-Barré Syndrome, Encephalitis, and Myelitis.

    Science.gov (United States)

    Muñoz, Laura S; Barreras, Paula; Pardo, Carlos A

    2016-09-01

    Zika virus (ZIKV) has caused a major infection outbreak in the Americas since 2015. In parallel with the ZIKV epidemic, an increase in cases of neurological disorders which include Guillain-Barré syndrome (GBS), encephalitis, and myelitis have been linked to the infection. We reviewed the evidence suggesting a relationship between ZIKV and neurological disorders in adults. A search of the literature supporting such link included databases such as PubMed and the World Health Organization (WHO) surveillance system. Through June 1, 2016, 761 publications were available on PubMed using the search word "Zika." Among those publications as well as surveillance reports released by the WHO and other health organizations, 20 articles linked ZIKV with neurological complications other than microcephaly. They corresponded to population and surveillance studies (n = 7), case reports (n = 9), case series (n = 3), and case-control studies (n = 1). Articles were also included if they provided information related to possible mechanisms of ZIKV neuropathogenesis. Evidence based on epidemiological and virological information supports the hypothesis that ZIKV infection is associated with GBS. Although cases of encephalopathy and myelitis have also been linked to ZIKV infection, the evidence is scarce and there is a need for virological, epidemiological, and controlled studies to better characterize such relationship. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  10. Oral immunization of mice with Japanese encephalitis virus envelope protein synthesized in Escherichia coli induces anti-viral antibodies.

    Science.gov (United States)

    Rauthan, Manish; Kaur, Rupinderjeet; Appaiahgari, Mohan Babu; Vrati, Sudhanshu

    2004-11-01

    In order to evaluate the possibility of developing an oral vaccine against Japanese encephalitis virus (JEV), mice were fed with recombinant JEV envelope (E) protein synthesized in Escherichia coli. The protein was administered orally to mice with or without an immunostimulatory cytosine-phosphate-guanosine (CpG) motif containing synthetic oligodeoxynucleotide (ODN) as an adjuvant. The immunized mice made high-titered anti-E and anti-JEV antibodies. Mice immunized with JEV E protein along with the ODN adjuvant produced higher antibody titers and these were predominantly IgG2a type. These antibodies, however, failed to neutralize JEV activity in vitro, and the immunization did not protect the mice against lethal JEV challenge. Splenocytes from the immunized mice secreted large amounts of interferon (IFN)-gamma and showed proliferation in the presence of JEV E protein. Our results indicate that JEV E protein delivered orally to mice together with ODN generated both humoral and cellular immune responses to JEV, and these were of the Th1 type.

  11. Babesia canis and tick-borne encephalitis virus (TBEV) co-infection in a sled dog.

    Science.gov (United States)

    Bajer, Anna; Rodo, Anna; Bednarska, Malgorzata; Mierzejewska, Ewa; Welc-Falęciak, Renata

    2013-01-01

    Sporting dogs, including sled dogs, are particularly prone to tick-borne infection either due to training/racing in forest areas or through visits to endemic areas. The aim was to present tick-borne infections in a 6-dog racing team after a race in Estonia. On the 4th day after return to Poland, the first dog presented with babesiosis symptoms and was diagnosed and treated accordingly. Next morning, the dog showed neurological symptoms and was diagnosed with tick-borne encephalitis (TBE). Diagnosis was confirmed by a high level of IgG antibodies (922 IU/ml), detected in serum 3 months later. The second dog presented with babesiosis symptoms on the 7th day after return. Babesia DNA was extracted from blood, amplified and sequenced to answer the question of whether the dogs became infected during the race in Estonia or in Poland. Sequencing of a fragment of Babesia 18S rDNA revealed that these two isolates were identical to one another and closely related to the B. canis sequence originally isolated from the dog and Dermacentor reticulatus ticks in Poland. Thus, this is the first confirmed case of B.canis and TBEV co-infection and first confirmed case of TBE in a dog in Poland.

  12. Fine mapping of a linear epitope on EDIII of Japanese encephalitis virus using a novel neutralizing monoclonal antibody.

    Science.gov (United States)

    Deng, Wen-Lei; Guan, Chi-Yu; Liu, Ke; Zhang, Xiao-Min; Feng, Xiu-Li; Zhou, Bin; Su, Xiao-Dong; Chen, Pu-Yan

    2014-01-22

    The domain III (EDIII) of the envelope protein of Japanese encephalitis virus (JEV) is proposed to play an essential role in JEV replication and infection; it is involved in binding to host receptors and contains specific epitopes that elicit neutralizing antibodies. However, most previous studies have not provided detailed molecular information about the functional epitopes on JEV EDIII protein. In this study, we described a monoclonal antibody (mAb 2B4) we produced and characterized by IFA, PRNT, ELISA and Western blot analyses. The results showed that mAb 2B4 was specific to JEV EDIII protein and possessed high neutralization activity against JEV in vitro. Furthermore, we found that the motif, (394)HHWH(397), was the minimal unit of the linear epitope recognized by mAb 2B4 through screening a phage-displayed random 12-mer peptide library. Using sequence alignment analysis it was found that this motif was highly conserved among JEV strains and was present in West Nile Virus (WNV). Indeed, ELISA data showed that this epitope could be recognized by both JEV-positive swine serum and WNV-positive swine serum. Notably, this linear epitope was highly hydrophilic and was located within the terminal end of a β-pleated sheet of EDIII. An analysis of the spatial conformation supported the possibility of inducing specific antibodies to this epitope. Taken together, we identified (394)HHWH(397) as an EDIII-specific linear epitope recognized by mAb 2B4, which would be beneficial for studying the pathogenic mechanism of JEV; and mAb 2B4 was also a potential diagnostic and therapeutic reagent. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Expression of particulate-form of Japanese encephalitis virus envelope protein in a stably transfected Drosophila cell line

    Directory of Open Access Journals (Sweden)

    Zhang Li

    2007-02-01

    Full Text Available Abstract Background Japanese encephalitis virus (JEV, a member of the family Flaviviridae, is an important mosquito-borne human pathogen. Its envelope glycoprotein (E is the major determinant of the pathogenicity and host immune responses. In the present study, we explored the feasibility of producing recombinant JEV E protein in the virus-free Drosophila expression system. Results The coding sequence for the signal sequence of premembrane and E protein was cloned into the Drosophila expression vector pAc5.1/V5-His. A Drosophila cell line S2 was cotransfected with this construct as well as a plasmid providing hygromycin B resistance. A cell line expressing the JEV E protein was selected by immunofluoresence, confocal microscopy, and western blot analysis using three different monoclonal antibodies directed against JEV E protein. This cell line was stable in the yield of JEV E protein during two months in vitro maintenance in the presence of hygromycin B. The results showed that the recombinant E protein had an expected molecular weight of about 50 kilodalton, was immunoreactive with all three monoclonal antibodies, and found in both the cytoplasm and culture supernatant. Sucrose gradient ultracentrifugation analysis revealed that the secreted E protein product was in a particulate form. It migrated to the sucrose fraction with a density of 1.13 g/ml. Balb/c mice immunised with the sucrose fraction containing the E protein particles developed specific antibodies. These data show that functioning JEV E protein was expressed in the stable S2 cell line. Conclusion The Drosophila expression system is a more convenient, cheaper and safer approach to the production of vaccine candidates and diagnostic reagents for JEV.

  14. Prevalence of Neutralizing Antibodies to Japanese Encephalitis Virus among High-Risk Age Groups in South Korea, 2010

    Science.gov (United States)

    Ju, Young Ran; Han, Myung Guk; Lee, Won-Ja; Jeong, Young Eui

    2016-01-01

    After an extensive vaccination policy, Japanese encephalitis (JE) was nearly eliminated since the mid-1980s in South Korea. Vaccination in children shifted the affected age of JE patients from children to adults. However, an abrupt increase in JE cases occurred in 2010, and this trend has continued. The present study aimed to investigate the prevalence of neutralizing antibodies to the JE virus (JEV) among high-risk age groups (≥40 years) in South Korea. A plaque reduction neutralization test was conducted to evaluate the prevalence of neutralizing antibodies to JEV in 945 subjects within four age groups (30–39, 40–49, 50–59, and 60–69 years) in 10 provinces. Of the 945 enrolled subjects, 927 (98.1%) exhibited antibodies against JEV. No significant differences were found in the prevalence of neutralizing antibodies according to sex, age, or occupation. However, there were significant differences in the plaque reduction rate according to age and occupation; oldest age group had a higher reduction rate, and subjects who were employed in agriculture or forestry also had a higher value than the other occupations. We also found that three provinces (Gangwon, Jeonnam, and Gyeongnam) had a relatively lower plaque reduction rate than the other locations. In addition, enzyme-linked immunosorbent assays were conducted to determine recent viral infections and 12 (2.2%) subjects were found to have been recently infected by the virus. In conclusion, the present study clearly indicated that the prevalence of neutralizing antibodies has been maintained at very high levels among adult age groups owing to vaccination or natural infections, or both. In the future, serosurveillance should be conducted periodically using more representative samples to better understand the population-level immunity to JE in South Korea. PMID:26807709

  15. Infection dynamics of western equine encephalomyelitis virus (Togaviridae: Alphavirus) in four strains of Culex tarsalis (Diptera: Culicidae): an immunocytochemical study.

    Science.gov (United States)

    Oviedo, Marco V Neira; Romoser, William S; James, Calvin Bl; Mahmood, Farida; Reisen, William K

    2011-04-18

    BACKGROUND: Vector competence describes the efficiency with which vector arthropods become infected with and transmit pathogens and depends on interactions between pathogen and arthropod genetics as well as environmental factors. For arbovirus transmission, the female mosquito ingests viremic blood, the virus infects and replicates in midgut cells, escapes from the midgut, and disseminates to other tissues, including the salivary glands. Virus-laden saliva is then injected into a new host. For transmission to occur, the virus must overcome several "barriers", including barriers to midgut infection and/or escape and salivary infection and/or escape. By examining the spatial/temporal infection dynamics of Culex tarsalis strains infected with western equine encephalomyelitis virus (WEEV), we identified tissue tropisms and potential tissue barriers, and evaluated the effects of viral dose and time postingestion. METHODS: Using immunostained paraffin sections, WEEV antigens were tracked in four Cx. tarsalis strains: two recently colonized California field strains - Coachella Valley, Riverside County (COAV) and Kern National Wildlife Refuge (KNWR); and two laboratory strains selected for WEEV susceptibility (high viremia producer, HVP), and WEEV resistance (WR). RESULTS AND CONCLUSIONS: Tissues susceptible to WEEV infection included midgut epithelium, neural ganglia, trachea, chorionated eggs, and salivary glands. Neuroendocrine cells in the retrocerebral complex were occasionally infected, indicating the potential for behavioral effects. The HVP and COAV strains vigorously supported viral growth, whereas the WR and KNWR strains were less competent. Consistent with earlier studies, WEEV resistance appeared to be related to a dose-dependent midgut infection barrier, and a midgut escape barrier. The midgut escape barrier was not dependent upon the ingested viral dose. Consistent with midgut infection modulation, disseminated infections were less common in the WR and KNWR

  16. Guillain-Barré Syndrome, Acute Disseminated Encephalomyelitis and Encephalitis Associated with Zika Virus Infection in Brazil: Detection of Viral RNA and Isolation of Virus during Late Infection.

    Science.gov (United States)

    Brito Ferreira, Maria Lucia; Antunes de Brito, Carlos Alexandre; Moreira, Álvaro José Porto; de Morais Machado, Maria Íris; Henriques-Souza, Adélia; Cordeiro, Marli Tenório; de Azevedo Marques, Ernesto Torres; Pena, Lindomar José

    2017-11-01

    Zika virus (ZIKV) emerged in Brazil in 2015, which was followed by an increase of Guillain-Barre Syndrome (GBS) cases. We report the epidemiological, clinical, and laboratory findings of the first six neurological cases associated with ZIKV in Brazil seen in a reference neurology hospital in Pernambuco, Brazil. In all cases, ZIKV was detected in serum and/or cerebrospinal fluid (CSF) samples. In this case series, four cases were defined as GBS, one as acute disseminated encephalomyelitis (ADEM) and the other as encephalitis. ZIKV was detected in all cases by RT-PCR and virus isolation was successful in two patients. The time between ZIKV acute symptoms and the development of neurological manifestations varied from 3 to 13 days and ZIKV was detected between 15 and 34 days after the initial symptoms. Our results highlight the need to include ZIKV as a differential diagnosis for neurological syndromes in countries with circulation of this arbovirus. Because the viremia in these patients appears to persist longer, direct diagnostic techniques such as RT-PCR and viral isolation should be considered even if it is after the acute phase of viral infection.

  17. [Japanese encephalitis in Southern Europe].

    Science.gov (United States)

    Cleton, Natalie; Koopmans, Marion; Braks, Marieta; Van Maanen, Kees; Reusken, Chantal

    2014-07-01

    In 2012, a fragment of the Japanese encephalitis virus (JEV) genome was isolated from a pool of Culex pipiens mosquitoes caught in 2010 and 2011 in Northern Italy. JEV has a broad geographical distribution in South and Southeast Asia and Oceania, and is the most important cause of viral encephalitis in Asia in humans and also causes encephalitis in horses and fertility problems in pigs. However, recently isolated JEV genome fragments in mosquitoes in Italy could be an indication of repeated introduction of JEV, enzootic circulation of JEV or a related virus in Southern Europe. Until more information is available, Japanese encephalitis remains a travel-related infectious disease for travellers to JEV endemic and epidemic areas outside of Europe.

  18. The risk of introduction of equine infectious anemia virus into USA via cloned horse embryos imported from Canada.

    Science.gov (United States)

    Asseged, B D; Habtemariam, T; Tameru, B; Nganwa, D

    2012-01-15

    Deriving horse oocytes in the USA is hampered by the lack of abattoirs processing horse carcasses which could provide abundant quantities of ovaries from slaughtered mares. Therefore, several cloning industries in the USA are attempting to import cloned horse embryos from Canada. Like any agricultural commodity, cloned embryos pose a risk of introduction of exotic animal diseases into the importing country. Under such circumstances, risk assessment could provide an objective, transparent, and internationally accepted means for evaluating the risk. This quantitative risk assessment (QRA) was initiated to determine the risk of introduction of Equine infectious anemia virus (EIAV) into the USA via cloned horse embryos imported from Canada. In assessing the risk, a structured knowledge base regarding cloning in relation to Equine infectious anemia (EIA) was first developed. Based on the knowledge base, a scenario tree was developed to determine conditions (with mathematical probabilities) that could lead to the introduction and maintenance of EIAV along the cloning pathway. Parameters for the occurrence of the event at each node were estimated using published literature. Using @Risk software and setting Monte Carlo simulation at 50,000 iterations, the probability of importing an EIAV-infected cloned horse embryo was 1.8 × 10(-9) (R = 1.5 × 10(-12) to 2.9 × 10(-8)). Taking into account the current protocol for equine cloning and assuming the yield of 5 to 30 clones per year, the possible number of EIAV-infected cloned horse embryos ranged from 2.0 × 10(-10) to 9.1 × 10(-5) (Mean = 1.4×10(-6)) per year. Consequently, it would take up to 1.5 × 10(7) (R = 1.6 × 10(4) to 5.1 × 10(10)) years for EIAV to be introduced into the USA. Based on the knowledge base and our critical pathway analysis, the biological plausibility of introducing EIAV into USA via cloned horse embryos imported from Canada is extremely low. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. Genetic Determinants of Japanese Encephalitis Virus Vaccine Strain SA14-14-2 That Govern Attenuation of Virulence in Mice.

    Science.gov (United States)

    Gromowski, Gregory D; Firestone, Cai-Yen; Whitehead, Stephen S

    2015-06-01

    The safety and efficacy of the live-attenuated Japanese encephalitis virus (JEV) SA14-14-2 vaccine are attributed to mutations that accumulated in the viral genome during its derivation. However, little is known about the contribution that is made by most of these mutations to virulence attenuation and vaccine immunogenicity. Here, we generated recombinant JEV (rJEV) strains containing JEV SA14-14-2 vaccine-specific mutations that are located in the untranslated regions (UTRs) and seven protein genes or are introduced from PCR-amplified regions of the JEV SA14-14-2 genome. The resulting mutant viruses were evaluated in tissue culture and in mice. The authentic JEV SA14-14-2 (E) protein, with amino acid substitutions L107F, E138K, I176V, T177A, E244G, Q264H, K279M, A315V, S366A, and K439R relative to the wild-type rJEV clone, was essential and sufficient for complete attenuation of neurovirulence. Individually, the nucleotide substitution T39A in the 5' UTR (5'-UTR-T39A), the capsid (C) protein amino acid substitution L66S (C-L66S), and the complete NS1/2A genome region containing 10 mutations each significantly reduced virus neuroinvasion but not neurovirulence. The levels of peripheral virulence attenuation imposed by the 5'-UTR-T39A and C-L66S mutations, individually, were somewhat mitigated in combination with other vaccine strain-specific mutations, which might be compensatory, and together did not affect immunogenicity. However, a marked reduction in immunogenicity was observed with the addition of the NS1/2A and NS5 vaccine virus genome regions. These results suggest that a second-generation recombinant vaccine can be rationally engineered to maximize levels of immunogenicity without compromising safety. The live-attenuated JEV SA14-14-2 vaccine has been vital for controlling the incidence of disease caused by JEV, particularly in rural areas of Asia where it is endemic. The vaccine was developed >25 years ago by passaging wild-type JEV strain SA14 in tissue

  20. Detection Of Caprine Arthritis Encephalitis Virus Gag-Gene By Rt ...

    African Journals Online (AJOL)

    Predominantly, cells of the monocyte-macrophage lineage were specifically infected by the virus as proviral DNA was detected in infected cultures by amplification of a 414 base-pair (bp) fragment of the viral gag-gene by Reverse Transcription- Polymerase Chain Reaction (RT-PCR) technique. The present study revealed ...

  1. Electron Tomography Analysis of Tick-Borne Encephalitis Virus Infection in Human Neurons

    Czech Academy of Sciences Publication Activity Database

    Bílý, Tomáš; Palus, Martin; Eyer, L.; Elsterová, Jana; Vancová, Marie; Růžek, Daniel

    2015-01-01

    Roč. 5, JUN 15 2015 (2015), s. 10745 ISSN 2045-2322 R&D Projects: GA ČR GAP502/11/2116; GA TA ČR(CZ) TE01020118 Institutional support: RVO:60077344 Keywords : dengue virus * replication sites * arboviruses Subject RIV: EE - Microbiology, Virology Impact factor: 5.228, year: 2015

  2. Rapid detection of equine influenza virus H3N8 subtype by insulated isothermal RT-PCR (iiRT-PCR) assay using the POCKIT™ Nucleic Acid Analyzer.

    Science.gov (United States)

    Balasuriya, Udeni B R; Lee, Pei-Yu Alison; Tiwari, Ashish; Skillman, Ashley; Nam, Bora; Chambers, Thomas M; Tsai, Yun-Long; Ma, Li-Juan; Yang, Pai-Chun; Chang, Hsiao-Fen Grace; Wang, Hwa-Tang Thomas

    2014-10-01

    Equine influenza (EI) is an acute, highly contagious viral respiratory disease of equids. Currently, equine influenza virus (EIV) subtype H3N8 continues to be the most important respiratory pathogen of horses in many countries around the world. The need to achieve a rapid diagnosis and to implement effective quarantine and movement restrictions is critical in controlling the spread of EIV. In this study, a novel, inexpensive and user-friendly assay based on an insulated isothermal RT-PCR (iiRT-PCR) method on the POCKIT™, a field-deployable device, was described and validated for point-of-need detection of EIV-H3N8 in clinical samples. The newly established iiRT-PCR assay targeting the EIV HA3 gene was evaluated for its sensitivity using in vitro transcribed (IVT) RNA, as well as ten-fold serial dilutions of RNA extracted from the prototype H3N8 strain A/equine/Miami/1/63. Inclusivity and exclusivity panels were tested for specificity evaluation. Published real-time RT-PCR (rRT-PCR) assays targeting the NP and HA3 genes were used as the reference standards for comparison of RNA extracted from field strains and from nasal swab samples collected from experimentally infected horses, respectively. Limit of detection with a 95% probability (LoD95%) was estimated to be 11copies of IVT RNA. Clinical sensitivity analysis using RNA prepared from serial dilutions of a prototype EIV (Miami 1/63/H3N8) showed that the iiRT-PCR assay was about 100-fold more sensitive than the rRT-PCR assay targeting the NP gene of EIV subtype H3N8. The iiRT-PCR assay identified accurately fifteen EIV H3N8 strains and two canine influenza virus (CIV) H3N8 strains, and did not cross-react with H6N2, H7N7, H1N1 subtypes or any other equine respiratory viral pathogens. Finally, 100% agreement was found between the iiRT-PCR assay and the universal influenza virus type A rRT-PCR assay in detecting the EIV A/equine/Kentucky/7/07 strain in 56 nasal swab samples collected from experimentally inoculated

  3. Prevalence of tick-borne encephalitis virus in Ixodes ricinus ticks in northern Europe with particular reference to Southern Sweden

    Science.gov (United States)

    2014-01-01

    Background In northern Europe, the tick-borne encephalitis virus (TBEV) of the European subtype is usually transmitted to humans by the common tick Ixodes ricinus. The aims of the present study are (i) to obtain up-to-date information on the TBEV prevalence in host-seeking I. ricinus in southern and central Sweden; (ii) to compile and review all relevant published records on the prevalence of TBEV in ticks in northern Europe; and (iii) to analyse and try to explain how the TBE virus can be maintained in natural foci despite an apparently low TBEV infection prevalence in the vector population. Methods To estimate the mean minimum infection rate (MIR) of TBEV in I. ricinus in northern Europe (i.e. Denmark, Norway, Sweden and Finland) we reviewed all published TBEV prevalence data for host-seeking I. ricinus collected during 1958–2011. Moreover, we collected 2,074 nymphs and 906 adults of I. ricinus from 29 localities in Sweden during 2008. These ticks were screened for TBEV by RT-PCR. Results The MIR for TBEV in nymphal and adult I. ricinus was 0.28% for northern Europe and 0.23% for southern Sweden. The infection prevalence of TBEV was significantly lower in nymphs (0.10%) than in adult ticks (0.55%). At a well-known TBEV-endemic locality, Torö island south-east of Stockholm, the TBEV prevalence (MIR) was 0.51% in nymphs and 4.48% in adults of I. ricinus. Conclusions If the ratio of nymphs to adult ticks in the TBEV-analysed sample differs from that in the I. ricinus population in the field, the MIR obtained will not necessarily reflect the TBEV prevalence in the field. The relatively low TBEV prevalence in the potential vector population recorded in most studies may partly be due to: (i) inclusion of uninfected ticks from the ‘uninfected areas’ surrounding the TBEV endemic foci; (ii) inclusion of an unrepresentative, too large proportion of immature ticks, compared to adult ticks, in the analysed tick pools; and (iii) shortcomings in the laboratory

  4. Comparison of Two Commercial Tick-Borne Encephalitis Virus IgG Enzyme-Linked Immunosorbent Assays.

    Science.gov (United States)

    Weissbach, Fabian H; Hirsch, Hans H

    2015-07-01

    Despite the availability of protective vaccines, tick-borne encephalitis virus (TBEV) infections have been increasingly reported to the European Centre for Disease Prevention and Control in the past 2 decades. Since the diagnosis of TBEV exposure relies on serological testing, we compared two commercial enzyme-linked immunosorbent assays (ELISAs), i.e., Immunozym FSME IgG assay (ELISA-1) and Euroimmun FSME Vienna IgG assay (ELISA-2). Both assays use whole TBEV antigens, but they differ in viral strains (Neudoerfl for ELISA-1 and K23 for ELISA-2) and cutoff values. In testing of samples from 398 healthy blood donors, ELISA-1 showed higher reactivity levels than ELISA-2 (P < 0.001), suggesting different assay properties. This finding was supported by Bland-Altman analysis of the optical density at 450 nm (OD450) (mean bias, +0.32 [95% limits of agreement, -0.31 to +0.95]) and persisted after transformation into Vienna units. Concordant results were observed for 276 sera (69%) (44 positive and 232 negative results). Discordant results were observed for 122 sera (31%); 15 were fully discordant, all being ELISA-1 positive and ELISA-2 negative, and 107 were partially discordant (101 being ELISA-1 indeterminate and ELISA-2 negative and 6 having positive or indeterminate reactivity in both ELISAs). Neutralization testing at a 1:10 dilution yielded positive results for 33 of 44 concordant positive sera, 1 of 15 fully discordant sera, and 1 of 33 partially discordant sera. Indirect immunofluorescence testing revealed high antibody titers of ≥100 for yellow fever virus in 18 cases and for dengue virus in one case, suggesting that cross-reactivity contributed to the ELISA-1 results. We conclude that (i) cross-reactivity among flaviviruses remains a limitation of TBEV serological testing, (ii) ELISA-2 revealed reasonable sensitivity and specificity for anti-TBEV IgG population screening of human sera, and (iii) neutralization testing is most specific and should be reserved

  5. Prevalence of tick-borne encephalitis virus in Ixodes ricinus ticks in northern Europe with particular reference to Southern Sweden.

    Science.gov (United States)

    Pettersson, John H-O; Golovljova, Irina; Vene, Sirkka; Jaenson, Thomas G T

    2014-03-11

    In northern Europe, the tick-borne encephalitis virus (TBEV) of the European subtype is usually transmitted to humans by the common tick Ixodes ricinus. The aims of the present study are (i) to obtain up-to-date information on the TBEV prevalence in host-seeking I. ricinus in southern and central Sweden; (ii) to compile and review all relevant published records on the prevalence of TBEV in ticks in northern Europe; and (iii) to analyse and try to explain how the TBE virus can be maintained in natural foci despite an apparently low TBEV infection prevalence in the vector population. To estimate the mean minimum infection rate (MIR) of TBEV in I. ricinus in northern Europe (i.e. Denmark, Norway, Sweden and Finland) we reviewed all published TBEV prevalence data for host-seeking I. ricinus collected during 1958-2011. Moreover, we collected 2,074 nymphs and 906 adults of I. ricinus from 29 localities in Sweden during 2008. These ticks were screened for TBEV by RT-PCR. The MIR for TBEV in nymphal and adult I. ricinus was 0.28% for northern Europe and 0.23% for southern Sweden. The infection prevalence of TBEV was significantly lower in nymphs (0.10%) than in adult ticks (0.55%). At a well-known TBEV-endemic locality, Torö island south-east of Stockholm, the TBEV prevalence (MIR) was 0.51% in nymphs and 4.48% in adults of I. ricinus. If the ratio of nymphs to adult ticks in the TBEV-analysed sample differs from that in the I. ricinus population in the field, the MIR obtained will not necessarily reflect the TBEV prevalence in the field. The relatively low TBEV prevalence in the potential vector population recorded in most studies may partly be due to: (i) inclusion of uninfected ticks from the 'uninfected areas' surrounding the TBEV endemic foci; (ii) inclusion of an unrepresentative, too large proportion of immature ticks, compared to adult ticks, in the analysed tick pools; and (iii) shortcomings in the laboratory techniques used to detect the virus that may be

  6. Transmission of equine influenza virus during an outbreak is characterized by frequent mixed infections and loose transmission bottlenecks.

    Science.gov (United States)

    Hughes, Joseph; Allen, Richard C; Baguelin, Marc; Hampson, Katie; Baillie, Gregory J; Elton, Debra; Newton, J Richard; Kellam, Paul; Wood, James L N; Holmes, Edward C; Murcia, Pablo R

    2012-12-01

    The ability of influenza A viruses (IAVs) to cross species barriers and evade host immunity is a major public health concern. Studies on the phylodynamics of IAVs across different scales - from the individual to the population - are essential for devising effective measures to predict, prevent or contain influenza emergence. Understanding how IAVs spread and evolve during outbreaks is critical for the management of epidemics. Reconstructing the transmission network during a single outbreak by sampling viral genetic data in time and space can generate insights about these processes. Here, we obtained intra-host viral sequence data from horses infected with equine influenza virus (EIV) to reconstruct the spread of EIV during a large outbreak. To this end, we analyzed within-host viral populations from sequences covering 90% of the infected yards. By combining gene sequence analyses with epidemiological data, we inferred a plausible transmission network, in turn enabling the comparison of transmission patterns during the course of the outbreak and revealing important epidemiological features that were not apparent using either approach alone. The EIV populations displayed high levels of genetic diversity, and in many cases we observed distinct viral populations containing a dominant variant and a number of related minor variants that were transmitted between infectious horses. In addition, we found evidence of frequent mixed infections and loose transmission bottlenecks in these naturally occurring populations. These frequent mixed infections likely influence the size of epidemics.

  7. Transmission of equine influenza virus during an outbreak is characterized by frequent mixed infections and loose transmission bottlenecks.

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    Joseph Hughes

    2012-12-01

    Full Text Available The ability of influenza A viruses (IAVs to cross species barriers and evade host immunity is a major public health concern. Studies on the phylodynamics of IAVs across different scales - from the individual to the population - are essential for devising effective measures to predict, prevent or contain influenza emergence. Understanding how IAVs spread and evolve during outbreaks is critical for the management of epidemics. Reconstructing the transmission network during a single outbreak by sampling viral genetic data in time and space can generate insights about these processes. Here, we obtained intra-host viral sequence data from horses infected with equine influenza virus (EIV to reconstruct the spread of EIV during a large outbreak. To this end, we analyzed within-host viral populations from sequences covering 90% of the infected yards. By combining gene sequence analyses with epidemiological data, we inferred a plausible transmission network, in turn enabling the comparison of transmission patterns during the course of the outbreak and revealing important epidemiological features that were not apparent using either approach alone. The EIV populations displayed high levels of genetic diversity, and in many cases we observed distinct viral populations containing a dominant variant and a number of related minor variants that were transmitted between infectious horses. In addition, we found evidence of frequent mixed infections and loose transmission bottlenecks in these naturally occurring populations. These frequent mixed infections likely influence the size of epidemics.

  8. 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.

  9. Targeted blockade in lethal West Nile virus encephalitis indicates a crucial role for very late antigen (VLA-4-dependent recruitment of nitric oxide-producing macrophages

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    Getts Daniel R

    2012-10-01

    Full Text Available Abstract Infiltration of Ly6Chi monocytes from the blood is a hallmark of viral encephalitis. In mice with lethal encephalitis caused by West Nile virus (WNV, an emerging neurotropic flavivirus, inhibition of Ly6Chi monocyte trafficking into the brain by anti-very late antigen (VLA-4 integrin antibody blockade at the time of first weight loss and leukocyte influx resulted in long-term survival of up to 60% of infected mice, with subsequent sterilizing immunity. This treatment had no effect on viral titers but appeared to be due to inhibition of Ly6Chi macrophage immigration. Although macrophages isolated from the infected brain induced WNV-specific CD4+ T-cell proliferation, T cells did not directly contribute to pathology, but are likely to be important in viral control, as antibody-mediated T-cell depletion could not reproduce the therapeutic benefit of anti-VLA-4. Instead, 70% of infiltrating inflammatory monocyte-derived macrophages were found to be making nitric oxide (NO. Furthermore, aminoguanidine-mediated inhibition of induced NO synthase activity in infiltrating macrophages significantly prolonged survival, indicating involvement of NO in the immunopathology. These data show for the first time the therapeutic effects of temporally targeting pathogenic NO-producing macrophages during neurotropic viral encephalitis.

  10. Tick borne encephalitis without cerebrospinal fluid pleocytosis

    OpenAIRE

    Stupica, Daša; Strle, Franc; Avšič-Županc, Tatjana; Logar, Mateja; Pečavar, Blaž; Bajrović, Fajko F

    2014-01-01

    Background Tick borne encephalitis is the most frequent vector-transmitted infectious disease of the central nervous system in Europe and Asia. The disease caused by European subtype of tick borne encephalitis virus has typically a biphasic clinical course with the second phase presenting as meningitis, meningoencephalitis, or meningoencephalomyelitis. Cerebrospinal fluid pleocytosis is considered a condition sine qua non for the diagnosis of neurologic involvement in tick borne encephalitis,...

  11. Japanese Encephalitis Virus Infection Rate and Detection of Genotype I From Culex tritaeniorhynchus Collected From Jiangsu, China.

    Science.gov (United States)

    Chu, Hongliang; Wu, Zhiming; Chen, Hongna; Li, Chunxiao; Guo, Xiaoxia; Liu, Ran; Wang, Gang; Zhou, Minghao; Zhao, Tongyan

    2017-07-01

    Information regarding the infection rate and genotype shifts for Japanese encephalitis virus (JEV) are important for JE vaccine application. In Jiangsu province, China, which is one of the provinces with a high prevalence of JE, JEV infection in swine and mosquitoes in certain cities has only been investigated in 2008-2009. Lianyungang City has one of the highest numbers of JE cases in Jiangsu province, and it has a high risk of JEV invasion via migrant birds. JEV infection in vectors in Lianyungang City, which has urban and rural parts, has not been investigated. In 2015-2016, we collected mosquitoes in cowsheds with ultraviolet light traps and detected JEV by reverse transcription-polymerase chain reaction (RT-PCR) method in Culex tritaeniorhynchus in Xintan village, Xuzhuang village, and Xiaogaozhuang village in Lianyungang City, China. The proportion of positive pools, which is calculated by the number of infected pools to the total number of pools tested in these villages, were 16.67%, 20.00%, and 4.17%, respectively, and the minimum infection rates, which is calculated as the ratio of the number of positive pools to the total number of mosquitoes tested, were 3.33‰, 4.00‰, and 0.83‰, respectively. Four JEV strains from positive samples were coded as LYG-1, LYG-2, LYG-3, and LYG-4, and the complete E genes were sequenced. Furthermore, the complete genome of LYG-3 was sequenced. The phylogenetic analysis indicated that all the four JEV strains belonged to genotype I-b. This is the first report of genotype I JEV strain in Jiangsu province. The high JEV infection rate in Culex tritaeniorhynchus indicated a high risk of JE reemergence in Lianyungang. The detected JEV strains may have similar antigenicity to that of SA14-14-2 according to molecular characters. These findings suggest that the vaccine can still be effective in Lianyungang.

  12. EXPERIMENTAL STUDIES ON ENCEPHALITIS

    Science.gov (United States)

    Webster, Leslie T.; Clow, Anna D.; Bauer, Johannes H.

    1935-01-01

    Anopheles quadrimaculatus mosquitoes, fed on mice in which encephalitis virus (St. Louis type) is present in the blood stream, take up and retain the virus for the duration of their lives. The titre of the virus in mosquitoes 4 hours after engorging on mice with a maximum blood stream infection represents about 10,000 lethal mouse intracerebral doses per mosquito. This titre drops during the following 2 weeks to about 100 lethal doses per mosquito, but from the 3rd week to the death of the mosquito, usually increases to approximately the original level and remains there. The titre of virus in mosquitoes which have engorged on mouse blood containing smaller quantities of virus exhibits the same drop and subsequent rise to the original level. The virus-containing mosquitoes did not infect mice or monkeys by biting. PMID:19870373

  13. Transient immune suppression of inapparent carriers infected with a principal neutralizing domain-deficient equine infectious anaemia virus induces neutralizing antibodies and lowers steady-state virus replication.

    Science.gov (United States)

    Craigo, Jodi K; Leroux, Caroline; Howe, Laryssa; Steckbeck, Jonathan D; Cook, Sheila J; Issel, Charles J; Montelaro, Ronald C

    2002-06-01

    The genetic variation of equine infectious anaemia virus (EIAV) clearly affects the antigenic properties of the viral envelope; however, effects on immunogenicity remain undefined, although widely assumed. Here, the immunogenicity is reported of a novel, neutralization-resistant, pony-isolate envelope EIAV(PV564DeltaPND) that contains a 14-residue deletion in the designated principal neutralizing domain (PND) of the gp90 protein. Two ponies inoculated with a chimeric virus, EIAV(DeltaPND), containing the EIAV(PV564DeltaPND) envelope in a reference provirus strain, remained asymptomatic through 14 months post-inoculation, producing high steady-state levels of envelope-specific antibodies but no detectable serum-neutralizing antibodies. Consequent dexamethasone-induced immune suppression produced characteristic EIA that resolved concomitantly with the development of high-titre, strain-specific, neutralizing antibodies and a 100-fold reduction in steady-state virus loads. These results demonstrate: natural variations in the EIAV envelope have profound effects on both antigenic and immunogenic properties; the PND is not required for neutralizing antibody responses; and transient immune suppression can enhance established host immunity to achieve more effective control of steady-state lentivirus replication.

  14. Rasmussen's Encephalitis

    Science.gov (United States)

    ... severe seizures, loss of motor skills and speech, paralysis on one side of the body (hemiparesis), inflammation of the brain (encephalitis), and mental deterioration. Most individuals with Rasmussen’s ...

  15. Horses

    Science.gov (United States)

    ... chronic or severe diarrhea. More Eastern Equine Encephalitis (EEE), Western Equine Encephalitis (WEE), St. Louis Encephalitis Virus (SLEV), and Venezuelan Encephalitis (VEE) EEE , WEE, SLEV , and VEE are viruses carried by ...

  16. Nonconvulsive Status Epilepticus Complicating Epstein-Barr Virus Encephalitis in a Child

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    Filippo Greco

    2014-01-01

    Full Text Available Children with acute encephalopathy show prolonged electrographic seizure activity consistent with nonconvulsive status epilepticus (NCSE. Pediatric NCSE is a heterogeneous clinical entity with poor outcome and different etiologies, including central nervous system infection, stroke, toxic-metabolic syndrome, and epileptic syndrome. We report a 4-year-old girl with seizure and behavioral changes in whom the analysis of cerebrospinal fluid by polymerase chain reaction was positive for Epstein-Barr virus. We emphasize the importance of electroencephalography (EEG, and particularly, of continuous EEG monitoring for early recognition and appropriate treatment of this condition.

  17. Characterization of a new 5' splice site within the caprine arthritis encephalitis virus genome: evidence for a novel auxiliary protein

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    Perrin Cécile

    2008-02-01

    Full Text Available Abstract Background Lentiviral genomes encode multiple structural and regulatory proteins. Expression of the full complement of viral proteins is accomplished in part by alternative splicing of the genomic RNA. Caprine arthritis encephalitis virus (CAEV and maedi-visna virus (MVV are two highly related small-ruminant lentiviruses (SRLVs that infect goats and sheep. Their genome seems to be less complex than those of primate lentiviruses since SRLVs encode only three auxiliary proteins, namely, Tat, Rev, and Vif, in addition to the products of gag, pol, and env genes common to all retroviruses. Here, we investigated the central part of the SRLV genome to identify new splice elements and their relevance in viral mRNA and protein expression. Results We demonstrated the existence of a new 5' splice (SD site located within the central part of CAEV genome, 17 nucleotides downstream from the SD site used for the rev mRNA synthesis, and perfectly conserved among SRLV strains. This new SD site was found to be functional in both transfected and infected cells, leading to the production of a transcript containing an open reading frame generated by the splice junction with the 3' splice site used for the rev mRNA synthesis. This open reading frame encodes two major protein isoforms of 18- and 17-kDa, named Rtm, in which the N-terminal domain shared by the Env precursor and Rev proteins is fused to the entire cytoplasmic tail of the transmembrane glycoprotein. Immunoprecipitations using monospecific antibodies provided evidence for the expression of the Rtm isoforms in infected cells. The Rtm protein interacts specifically with the cytoplasmic domain of the transmembrane glycoprotein in vitro, and its expression impairs the fusion activity of the Env protein. Conclusion The characterization of a novel CAEV protein, named Rtm, which is produced by an additional multiply-spliced mRNA, indicated that the splicing pattern of CAEV genome is more complex than

  18. Neutralising antibodies for Mayaro virus in Pantanal, Brazil

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    Alex Pauvolid-Corrêa

    2015-02-01

    Full Text Available The Pantanal hosts diverse wildlife species and therefore is a hotspot for arbovirus studies in South America. A serosurvey for Mayaro virus (MAYV, eastern (EEEV, western (WEEV and Venezuelan (VEEV equine encephalitis viruses was conducted with 237 sheep, 87 free-ranging caimans and 748 equids, including 37 collected from a ranch where a neurologic disorder outbreak had been recently reported. Sera were tested for specific viral antibodies using plaque-reduction neutralisation test. From a total of 748 equids, of which 264 were immunised with vaccine composed of EEEV and WEEV and 484 had no history of immunisation, 10 (1.3% were seropositive for MAYV and two (0.3% for VEEV using criteria of a ≥ 4-fold antibody titre difference. Among the 484 equids without history of immunisation, 48 (9.9% were seropositive for EEEV and four (0.8% for WEEV using the same criteria. Among the sheep, five were sero- positive for equine encephalitis alphaviruses, with one (0.4% for EEEV, one (0.4% for WEEV and three (1.3% for VEEV. Regarding free-ranging caimans, one (1.1% and three (3.4%, respectively, had low titres for neutralising antibodies to VEEV and undetermined alphaviruses. The neurological disorder outbreak could not be linked to the alphaviruses tested. Our findings represent strong evidence that MAYV and all equine encephalitis alphaviruses circulated in the Pantanal.

  19. Neutralising antibodies for Mayaro virus in Pantanal, Brazil.

    Science.gov (United States)

    Pauvolid-Corrêa, Alex; Juliano, Raquel Soares; Campos, Zilca; Velez, Jason; Nogueira, Rita Maria Ribeiro; Komar, Nicholas

    2015-02-01

    The Pantanal hosts diverse wildlife species and therefore is a hotspot for arbovirus studies in South America. A serosurvey for Mayaro virus (MAYV), eastern (EEEV), western (WEEV) and Venezuelan (VEEV) equine encephalitis viruses was conducted with 237 sheep, 87 free-ranging caimans and 748 equids, including 37 collected from a ranch where a neurologic disorder outbreak had been recently reported. Sera were tested for specific viral antibodies using plaque-reduction neutralisation test. From a total of 748 equids, of which 264 were immunised with vaccine composed of EEEV and WEEV and 484 had no history of immunisation, 10 (1.3%) were seropositive for MAYV and two (0.3%) for VEEV using criteria of a ≥ 4-fold antibody titre difference. Among the 484 equids without history of immunisation, 48 (9.9%) were seropositive for EEEV and four (0.8%) for WEEV using the same criteria. Among the sheep, five were sero- positive for equine encephalitis alphaviruses, with one (0.4%) for EEEV, one (0.4%) for WEEV and three (1.3%) for VEEV. Regarding free-ranging caimans, one (1.1%) and three (3.4%), respectively, had low titres for neutralising antibodies to VEEV and undetermined alphaviruses. The neurological disorder outbreak could not be linked to the alphaviruses tested. Our findings represent strong evidence that MAYV and all equine encephalitis alphaviruses circulated in the Pantanal.

  20. Equination (inoculation of horsepox): An early alternative to vaccination (inoculation of cowpox) and the potential role of horsepox virus in the origin of the smallpox vaccine.

    Science.gov (United States)

    Esparza, José; Schrick, Livia; Damaso, Clarissa R; Nitsche, Andreas

    2017-12-19

    For almost 150 years after Edward Jenner had published the "Inquiry" in 1798, it was generally assumed that the cowpox virus was the vaccine against smallpox. It was not until 1939 when it was shown that vaccinia, the smallpox vaccine virus, was serologically related but different from the cowpox virus. In the absence of a known natural host, vaccinia has been considered to be a laboratory virus that may have originated from mutational or recombinational events involving cowpox virus, variola viruses or some unknown ancestral Orthopoxvirus. A favorite candidate for a vaccinia ancestor has been the horsepox virus. Edward Jenner himself suspected that cowpox derived from horsepox and he also believed that "matter" obtained from either disease could be used as preventative of smallpox. During the 19th century, inoculation with cowpox (vaccination) was used in Europe alongside with inoculation with horsepox (equination) to prevent smallpox. Vaccine-manufacturing practices during the 19th century may have resulted in the use of virus mixtures, leading to different genetic modifications that resulted in present-day vaccinia strains. Horsepox, a disease previously reported only in Europe, has been disappearing on that continent since the beginning of the 20th century and now seems to have become extinct, although the virus perhaps remains circulating in an unknown reservoir. Genomic sequencing of a horsepox virus isolated in Mongolia in 1976 indicated that, while closely related to vaccinia, this horsepox virus contained additional, potentially ancestral sequences absent in vaccinia. Recent genetic analyses of extant vaccinia viruses have revealed that some strains contain ancestral horsepox virus genes or are phylogenetically related to horsepox virus. We have recently reported that a commercially produced smallpox vaccine, manufactured in the United States in 1902, is genetically highly similar to horsepox virus, providing a missing link in this 200-year-old mystery

  1. Identification of a novel equine infectious anemia virus field strain isolated from feral horses in southern Japan.

    Science.gov (United States)

    Dong, Jian-Bao; Zhu, Wei; Cook, Frank R; Goto, Yoshitaka; Horii, Yoichiro; Haga, Takeshi

    2013-02-01

    Although equine infectious anemia (EIA) was described more than 150 years ago, complete genomic sequences have only been obtained from two field strains of EIA virus (EIAV), EIAV(Wyoming) and EIAV(Liaoning). In 2011, EIA was detected within the distinctive feral Misaki horse population that inhabits the Toi-Cape area of southern Japan. Complete proviral sequences comprising a novel field strain were amplified directly from peripheral blood of one of these EIAV-infected horses and characterized by nucleotide sequencing. The complete provirus of Miyazaki2011-A strain is 8208 bp in length with an overall genomic organization typical of EIAV. However, this field isolate possesses just 77.2 and 78.7 % nucleotide sequence identity with the EIAV(Wyoming) and EIAV(Liaoning) strains, respectively, while similarity plot analysis suggested all three strains arose independently. Furthermore, phylogenetic studies using sequences obtained from all EIAV-infected Misaki horses against known viral strains strongly suggests these Japanese isolates comprise a separate monophyletic group.

  2. Detection and differentiation of genotype I and III Japanese encephalitis virus in mosquitoes by multiplex reverse transcriptase-polymerase chain reaction.

    Science.gov (United States)

    Chen, Y Y; Lin, J W; Fan, Y C; Chiou, S S

    2014-02-01

    Japanese encephalitis (JE) is a disease that threatens both human and animal populations in Asian countries, and the causative agent of JE, Japanese encephalitis virus (JEV), has recently changed from genotype III (GIII) to genotype I (GI). However, a test for the rapid differentiation of GI and GIII JEV is still unavailable, especially one that can be used for mosquito-based surveillance. We have designed GI- and GIII-specific primer sets for the rapid detection and differentiation of GI and GIII JEV by multiplex reverse transcriptase-polymerase chain reaction (multiplex RT-PCR). The GI-specific and GIII-specific primer sets were able to specifically amplify the target gene from GI and GIII JEV, respectively. The limitations of detection were 0.00225 and 0.225 pfu for the GI-specific and GIII-specific primers, respectively. Using a mixture of GI-specific and GIII-specific primers, the multiplex RT-PCR was able to specifically detect and differentiate GI and GIII JEV. The multiplex RT-PCR was able to successfully differentiate GI and GIII virus in JEV-infected mosquitoes. Thus, a sensitive and specific multiplex RT-PCR system for the rapid detection and differentiation of GI and GIII JEV has been developed, and this test is likely to be valuable when carrying out mosquito-based JEV surveillance. © 2012 Blackwell Verlag GmbH.

  3. Prevalence of tick borne encephalitis virus in tick nymphs in relation to climatic factors on the southern coast of Norway

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    Andreassen Ashild

    2012-08-01

    Full Text Available Abstract Background Tick-borne encephalitis (TBE is among the most important vector borne diseases of humans in Europe and is currently identified as a major health problem in many countries. TBE endemic zones have expanded over the past two decades, as well as the number of reported cases within endemic areas. Multiple factors are ascribed for the increased incidence of TBE, including climatic change. The number of TBE cases has also increased in Norway over the past decade, and the human cases cluster along the southern coast of Norway. In Norway the distribution and prevalence of TBE virus (TBEV in tick populations is largely unknown. The objectives of this study were to estimate the TBEV prevalence in Ixodes ricinus from seven locations and to assess the relationship between the TBEV prevalence and site-specific climatic variables. Methods A total of 5630 questing nymphs were collected and analyzed in pools of ten. All pools were screened with an in-house real-time RT-PCR, and the positive pools were pyrosequenced. Two methods, minimum infection rate (MIR and a frequentist method (EPP for pooled prevalence estimations were calculated and compared. Climatic data were descriptively compared to the corresponding EPP of each location in order to explain variations in TBEV prevalence. Results The seven foci of TBEV had an estimated overall prevalence (EPP in pools of nymphs combined, of 0.53% with 95% CI (0.35–0.75, with point prevalence ranging between 0.11%–1.22%. The sites with the highest point prevalences were within the municipalities which had the highest numbers of registered TBE cases. The results indicate that the location with highest point prevalence had the highest relative mean humidity and lowest mean saturation deficit and vice versa for the lowest EPP. Conclusion Our study confirms the existence of TBEV endemic foci in Norway. These results are of importance to increase the awareness of TBEV infections in Norway and could be

  4. Distinct dictation of Japanese encephalitis virus-induced neuroinflammation and lethality via triggering TLR3 and TLR4 signal pathways.

    Science.gov (United States)

    Han, Young Woo; Choi, Jin Young; Uyangaa, Erdenebelig; Kim, Seong Bum; Kim, Jin Hyoung; Kim, Bum Seok; Kim, Koanhoi; Eo, Seong Kug

    2014-09-01

    Japanese encephalitis (JE) is major emerging neurologic disease caused by JE virus. To date, the impact of TLR molecules on JE progression has not been addressed. Here, we determined whether each TLR modulates JE, using several TLR-deficient mouse strains (TLR2, TLR3, TLR4, TLR7, TLR9). Surprisingly, among the tested TLR-deficient mice there were contrasting results in TLR3(-/-) and TLR4(-/-) mice, i.e. TLR3(-/-) mice were highly susceptible to JE, whereas TLR4(-/-) mice showed enhanced resistance to JE. TLR3 ablation induced severe CNS inflammation characterized by early infiltration of inflammatory CD11b(+)Ly-6Chigh monocytes along with profoundly increased viral burden, proinflammatory cytokine/chemokine expression as well as BBB permeability. In contrast, TLR4(-/-) mice showed mild CNS inflammation manifested by reduced viral burden, leukocyte infiltration and proinflammatory cytokine expression. Interestingly, TLR4 ablation provided potent in vivo systemic type I IFN innate response, as well as ex vivo type I IFN production associated with strong induction of antiviral PRRs (RIG-I, MDA5), transcription factors (IRF-3, IRF-7), and IFN-dependent (PKR, Oas1, Mx) and independent ISGs (ISG49, ISG54, ISG56) by alternative activation of IRF3 and NF-κB in myeloid-derived DCs and macrophages, as compared to TLR3(-/-) myeloid-derived cells which were more permissive to viral replication through impaired type I IFN innate response. TLR4 ablation also appeared to mount an enhanced type I IFN innate and humoral, CD4(+) and CD8(+) T cell responses, which were mediated by altered immune cell populations (increased number of plasmacytoid DCs and NK cells, reduced CD11b(+)Ly-6C(high) monocytes) and CD4(+)Foxp3(+) Treg number in lymphoid tissue. Thus, potent type I IFN innate and adaptive immune responses in the absence of TLR4 were closely coupled with reduced JE lethality. Collectively, these results suggest that a balanced triggering of TLR signal array by viral components

  5. Distinct dictation of Japanese encephalitis virus-induced neuroinflammation and lethality via triggering TLR3 and TLR4 signal pathways.

    Directory of Open Access Journals (Sweden)

    Young Woo Han

    2014-09-01

    Full Text Available Japanese encephalitis (JE is major emerging neurologic disease caused by JE virus. To date, the impact of TLR molecules on JE progression has not been addressed. Here, we determined whether each TLR modulates JE, using several TLR-deficient mouse strains (TLR2, TLR3, TLR4, TLR7, TLR9. Surprisingly, among the tested TLR-deficient mice there were contrasting results in TLR3(-/- and TLR4(-/- mice, i.e. TLR3(-/- mice were highly susceptible to JE, whereas TLR4(-/- mice showed enhanced resistance to JE. TLR3 ablation induced severe CNS inflammation characterized by early infiltration of inflammatory CD11b(+Ly-6Chigh monocytes along with profoundly increased viral burden, proinflammatory cytokine/chemokine expression as well as BBB permeability. In contrast, TLR4(-/- mice showed mild CNS inflammation manifested by reduced viral burden, leukocyte infiltration and proinflammatory cytokine expression. Interestingly, TLR4 ablation provided potent in vivo systemic type I IFN innate response, as well as ex vivo type I IFN production associated with strong induction of antiviral PRRs (RIG-I, MDA5, transcription factors (IRF-3, IRF-7, and IFN-dependent (PKR, Oas1, Mx and independent ISGs (ISG49, ISG54, ISG56 by alternative activation of IRF3 and NF-κB in myeloid-derived DCs and macrophages, as compared to TLR3(-/- myeloid-derived cells which were more permissive to viral replication through impaired type I IFN innate response. TLR4 ablation also appeared to mount an enhanced type I IFN innate and humoral, CD4(+ and CD8(+ T cell responses, which were mediated by altered immune cell populations (increased number of plasmacytoid DCs and NK cells, reduced CD11b(+Ly-6C(high monocytes and CD4(+Foxp3(+ Treg number in lymphoid tissue. Thus, potent type I IFN innate and adaptive immune responses in the absence of TLR4 were closely coupled with reduced JE lethality. Collectively, these results suggest that a balanced triggering of TLR signal array by viral components

  6. Allelic Variation in CXCL16 Determines CD3+ T Lymphocyte Susceptibility to Equine Arteritis Virus Infection and Establishment of Long-Term Carrier State in the Stallion.

    Science.gov (United States)

    Sarkar, Sanjay; Bailey, Ernest; Go, Yun Young; Cook, R Frank; Kalbfleisch, Ted; Eberth, John; Chelvarajan, R Lakshman; Shuck, Kathleen M; Artiushin, Sergey; Timoney, Peter J; Balasuriya, Udeni B R

    2016-12-01

    Equine arteritis virus (EAV) is the causative agent of equine viral arteritis (EVA), a respiratory, systemic, and reproductive disease of horses and other equid species. Following natural infection, 10-70% of the infected stallions can become persistently infected and continue to shed EAV in their semen for periods ranging from several months to life. Recently, we reported that some stallions possess a subpopulation(s) of CD3+ T lymphocytes that are susceptible to in vitro EAV infection and that this phenotypic trait is associated with long-term carrier status following exposure to the virus. In contrast, stallions not possessing the CD3+ T lymphocyte susceptible phenotype are at less risk of becoming long-term virus carriers. A genome wide association study (GWAS) using the Illumina Equine SNP50 chip revealed that the ability of EAV to infect CD3+ T lymphocytes and establish long-term carrier status in stallions correlated with a region within equine chromosome 11. Here we identified the gene and mutations responsible for these phenotypes. Specifically, the work implicated three allelic variants of the equine orthologue of CXCL16 (EqCXCL16) that differ by four non-synonymous nucleotide substitutions (XM_00154756; c.715 A → T, c.801 G → C, c.804 T → A/G, c.810 G → A) within exon 1. This resulted in four amino acid changes with EqCXCL16S (XP_001504806.1) having Phe, His, Ile and Lys as compared to EqCXL16R having Tyr, Asp, Phe, and Glu at 40, 49, 50, and 52, respectively. Two alleles (EqCXCL16Sa, EqCXCL16Sb) encoded identical protein products that correlated strongly with long-term EAV persistence in stallions (PCD3+ T lymphocyte susceptibility to EAV infection. The third (EqCXCL16R) was associated with in vitro CD3+ T lymphocyte resistance to EAV infection and a significantly lower probability for establishment of the long-term carrier state (viral persistence) in the male reproductive tract. EqCXCL16Sa and EqCXCL16Sb exert a dominant mode of inheritance

  7. Allelic Variation in CXCL16 Determines CD3+ T Lymphocyte Susceptibility to Equine Arteritis Virus Infection and Establishment of Long-Term Carrier State in the Stallion.

    Directory of Open Access Journals (Sweden)

    Sanjay Sarkar

    2016-12-01

    Full Text Available Equine arteritis virus (EAV is the causative agent of equine viral arteritis (EVA, a respiratory, systemic, and reproductive disease of horses and other equid species. Following natural infection, 10-70% of the infected stallions can become persistently infected and continue to shed EAV in their semen for periods ranging from several months to life. Recently, we reported that some stallions possess a subpopulation(s of CD3+ T lymphocytes that are susceptible to in vitro EAV infection and that this phenotypic trait is associated with long-term carrier status following exposure to the virus. In contrast, stallions not possessing the CD3+ T lymphocyte susceptible phenotype are at less risk of becoming long-term virus carriers. A genome wide association study (GWAS using the Illumina Equine SNP50 chip revealed that the ability of EAV to infect CD3+ T lymphocytes and establish long-term carrier status in stallions correlated with a region within equine chromosome 11. Here we identified the gene and mutations responsible for these phenotypes. Specifically, the work implicated three allelic variants of the equine orthologue of CXCL16 (EqCXCL16 that differ by four non-synonymous nucleotide substitutions (XM_00154756; c.715 A → T, c.801 G → C, c.804 T → A/G, c.810 G → A within exon 1. This resulted in four amino acid changes with EqCXCL16S (XP_001504806.1 having Phe, His, Ile and Lys as compared to EqCXL16R having Tyr, Asp, Phe, and Glu at 40, 49, 50, and 52, respectively. Two alleles (EqCXCL16Sa, EqCXCL16Sb encoded identical protein products that correlated strongly with long-term EAV persistence in stallions (P<0.000001 and are required for in vitro CD3+ T lymphocyte susceptibility to EAV infection. The third (EqCXCL16R was associated with in vitro CD3+ T lymphocyte resistance to EAV infection and a significantly lower probability for establishment of the long-term carrier state (viral persistence in the male reproductive tract. EqCXCL16Sa and

  8. Comparison of two modern vaccines and previous influenza infection against challenge with an equine influenza virus from the Australian 2007 outbreak.

    Science.gov (United States)

    Bryant, Neil A; Paillot, Romain; Rash, Adam S; Medcalf, Elizabeth; Montesso, Fernando; Ross, Julie; Watson, James; Jeggo, Martyn; Lewis, Nicola S; Newton, J Richard; Elton, Debra M

    2010-01-01

    During 2007, large outbreaks of equine influenza (EI) caused by Florida sublineage Clade 1 viruses affected horse populations in Japan and Australia. The likely protection that would be provided by two modern vaccines commercially available in the European Union (an ISCOM-based and a canarypox-based vaccine) at the time of the outbreaks was determined. Vaccinated ponies were challenged with a representative outbreak isolate (A/eq/Sydney/2888-8/07) and levels of protection were compared.A group of ponies infected 18 months previously with a phylogenetically-related isolate from 2003 (A/eq/South Africa/4/03) was also challenged with the 2007 outbreak virus. After experimental infection with A/eq/Sydney/2888-8/07, unvaccinated control ponies all showed clinical signs of infection together with virus shedding. Protection achieved by both vaccination or long-term immunity induced by previous exposure to equine influenza virus (EIV) was characterised by minor signs of disease and reduced virus shedding when compared with unvaccinated control ponies. The three different methods of virus titration in embryonated hens' eggs, EIV NP-ELISA and quantitative RT-PCR were used to monitor EIV shedding and results were compared. Though the majority of previously infected ponies had low antibody levels at the time of challenge, they demonstrated good clinical protection and limited virus shedding. In summary, we demonstrate that vaccination with current EIV vaccines would partially protect against infection with A/eq/Sydney/2888-8/07-like strains and would help to limit the spread of disease in our vaccinated horse population. INRA, EDP Sciences, 2009

  9. Simultaneous detection and differentiation of dengue virus serotypes 1-4, Japanese encephalitis virus, and West Nile virus by a combined reverse-transcription loop-mediated isothermal amplification assay

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    Yin Jianhua

    2011-07-01

    Full Text Available Abstract Background Rapid identification and differentiation of mosquito-transmitted flaviviruses in acute-phase sera of patients and field-caught vector mosquitoes are important for the prediction and prevention of large-scale epidemics. Results We developed a flexible reverse-transcription loop-mediated isothermal amplification (RT-LAMP unit for the detection and differentiation of dengue virus serotypes 1-4 (DENV1-4, Japanese encephalitis virus (JEV, and West Nile virus (WNV. The unit efficiently amplified the viral genomes specifically at wide ranges of viral template concentrations, and exhibited similar amplification curves as monitored by a real-time PCR engine. The detection limits of the RT-LAMP unit were 100-fold higher than that of RT-PCR in 5 of the six flaviviruses. The results on specificity indicated that the six viruses in the assay had no cross-reactions with each other. By examining 66 viral strains of DENV1-4 and JEV, the unit identified the viruses with 100% accuracy and did not cross-react with influenza viruses and hantaviruses. By screening a panel of specimens containing sera of 168 patients and 279 pools of field-caught blood sucked mosquitoes, results showed that this unit is high feasible in clinical settings and epidemiologic field, and it obtained results 100% correlated with real-time RT-PCR. Conclusions The RT-LAMP unit developed in this study is able to quickly detect and accurately differentiate the six kinds of flaviviruses, which makes it extremely feasible for screening these viruses in acute-phase sera of the patients and in vector mosquitoes without the need of high-precision instruments.

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

    Science.gov (United States)

    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

  11. The NS3 and NS4A genes as the targets of RNA interference inhibit replication of Japanese encephalitis virus in vitro and in vivo.

    Science.gov (United States)

    Yuan, Lei; Wu, Rui; Liu, Hanyang; Wen, Xintian; Huang, Xiaobo; Wen, Yiping; Ma, Xiaoping; Yan, Qigui; Huang, Yong; Zhao, Qin; Cao, Sanjie

    2016-12-15

    Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus that can cause acute encephalitis with a high fatality rate. RNA interference (RNAi) is a powerful tool to silence gene expression and a potential therapy for virus infection. In this study, the antiviral ability of eight shRNA expression plasmids targeting different sites of the NS3 and NS4A genes of JEV was determined in BHK21 cells and mice. The pGP-NS3-3 and pGP-NS4A-4 suppressed 93.9% and 82.0% of JEV mRNA in cells, respectively. The virus titer in cells was reduced approximately 950-fold by pretreating with pGP-NS3-4, and 640-fold by pretreating with pGP-NS4A-4. The results of western blot and immunofluorescence analysis showed JEV E protein and viral load in cells were remarkably inhibited by shRNA expression plasmids. The viral load in brains of mice pretreated with pGP-NS3-4 or pGP-NS4A-4 were reduced approximately 2400-fold and 800-fold, respectively, and the survival rate of mice challenged with JEV were 70% and 50%, respectively. However, the antiviral ability of shRNA expression plasmids was decreased over time. This study indicates that RNAi targeting of the NS3 and NS4A genes of JEV can sufficiently inhibit the replication of JEV in vitro and in vivo, and NS3 and NS4A genes might be potential targets of molecular therapy for JEV infection. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Little evidence of avian or equine influenza virus infection among a cohort of Mongolian adults with animal exposures, 2010-2011.

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    Nyamdavaa Khurelbaatar

    Full Text Available Avian (AIV and equine influenza virus (EIV have been repeatedly shown to circulate among Mongolia's migrating birds or domestic horses. In 2009, 439 Mongolian adults, many with occupational exposure to animals, were enrolled in a prospective cohort study of zoonotic influenza transmission. Sera were drawn upon enrollment and again at 12 and 24 months. Participants were contacted monthly for 24 months and queried regarding episodes of acute influenza-like illnesses (ILI. Cohort members confirmed to have acute influenza A infections, permitted respiratory swab collections which were studied with rRT-PCR for influenza A. Serologic assays were performed against equine, avian, and human influenza viruses. Over the 2 yrs of follow-up, 100 ILI investigations in the cohort were conducted. Thirty-six ILI cases (36% were identified as influenza A infections by rRT-PCR; none yielded evidence for AIV or EIV. Serological examination of 12 mo and 24 mo annual sera revealed 37 participants had detectable antibody titers (≥1∶10 against studied viruses during the course of study follow-up: 21 against A/Equine/Mongolia/01/2008(H3N8; 4 against an avian A/Teal/Hong Kong/w3129(H6N1, 11 against an avian-like A/Hong Kong/1073/1999(H9N2, and 1 against an avian A/Migrating duck/Hong Kong/MPD268/2007(H10N4 virus. However, all such titers were <1∶80 and none were statistically associated with avian or horse exposures. A number of subjects had evidence of seroconversion to zoonotic viruses, but the 4-fold titer changes were again not associated with avian or horse exposures. As elevated antibodies against seasonal influenza viruses were high during the study period, it seems likely that cross-reacting antibodies against seasonal human influenza viruses were a cause of the low-level seroreactivity against AIV or EIV. Despite the presence of AIV and EIV circulating among wild birds and horses in Mongolia, there was little evidence of AIV or EIV infection in this

  13. Transduction of photoreceptors with equine infectious anemia virus lentiviral vectors: safety and biodistribution of StarGen for Stargardt disease.

    Science.gov (United States)

    Binley, Katie; Widdowson, Peter; Loader, Julie; Kelleher, Michelle; Iqball, Sharifah; Ferrige, Georgina; de Belin, Jackie; Carlucci, Marie; Angell-Manning, Diana; Hurst, Felicity; Ellis, Scott; Miskin, James; Fernandes, Alcides; Wong, Paul; Allikmets, Rando; Bergstrom, Christopher; Aaberg, Thomas; Yan, Jiong; Kong, Jian; Gouras, Peter; Prefontaine, Annick; Vezina, Mark; Bussieres, Martin; Naylor, Stuart; Mitrophanous, Kyriacos A

    2013-06-12

    StarGen is an equine infectious anemia virus (EIAV)-based lentiviral vector that expresses the photoreceptor-specific adenosine triphosphate (ATP)-binding cassette transporter (ABCA4) protein that is mutated in Stargardt disease (STGD1), a juvenile macular dystrophy. EIAV vectors are able to efficiently transduce rod and cone photoreceptors in addition to retinal pigment epithelium in the adult macaque and rabbit retina following subretinal delivery. The safety and biodistribution of StarGen following subretinal delivery in macaques and rabbits was assessed. Regular ophthalmic examinations, IOP measurements, ERG responses, and histopathology were carried out in both species to compare control and vector-treated eyes. Tissue and fluid samples were obtained to evaluate the persistence, biodistribution, and shedding of the vector following subretinal delivery. Ophthalmic examinations revealed a slightly higher level of inflammation in StarGen compared with control treated eyes in both species. However, inflammation was transient and no overt toxicity was observed in StarGen treated eyes and there were no abnormal clinical findings. There was no StarGen-associated rise in IOP or abnormal ERG response in either rabbits or macaques. Histopathologic examination of the eyes did not reveal any detrimental changes resulting from subretinal administration of StarGen. Although antibodies to StarGen vector components were detected in rabbit but not macaque serum, this immunologic response did not result in any long-term toxicity. Biodistribution analysis demonstrated that the StarGen vector was restricted to the ocular compartment. In summary, these studies demonstrate StarGen to be well tolerated and localized following subretinal administration.

  14. Health and epidemiological approaches of Trypanosoma evansi and equine infectious anemia virus in naturally infected horses at southern Pantanal.

    Science.gov (United States)

    Parreira, Daniela R; Jansen, Ana M; Abreu, Urbano G P; Macedo, Gabriel C; Silva, Antônia R S; Mazur, Carlos; Andrade, Gisele B; Herrera, Heitor M

    2016-11-01

    Equine infectious anemia virus (EIAV) and Trypanossoma evansi are endemic in Brazilian Pantanal Biome, an important area for livestock production. In this sense, we evaluated the epidemiological single and co-infection effects of T. evansi and EIAV in naturally infected horses in the southern Pantanal wetland by serological tests and hematological assays. Both higher seroprevalence and heath poor condition of the sampled animals were associated with differences in horse management between farms. We found that the negative animals for both infectious agents (NN) represented the major group in F1 (37%), and the smallest group in F2 (19%). Furthermore, we recorded higher EIAV seroprevalence (56%) in F2, compared to F1 (38%). We observed that T. evansi infection was mostly related to young horses, as seen by their higher seroprevalence, ranging from 70.7% in the beginning of the rainy season to 81% in the end of flood period, in comparison with the values of 42% and 68%, respectively, in working animals. on the other hand, working animals showed a higher seroprevalence for EIAV (48%) in both seasons than young horses. We observed that the management of working horses could be a risk factor of EIAV infection. On the other hand, as T. evansi is maintained in the study region by many species of wild mammals, the mechanical transmission through blood-sucking vectors ensures the infection to horses since early. Our results showed that single or co-infection by EIAV and T. evansi caused different degree of anemia in the infected animals. Moreover, the health of horses in Brazilian Pantanal is also influenced by differences in horse management and environmental circumstances. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Identification and Analysis of Differentially-Expressed microRNAs in Japanese Encephalitis Virus-Infected PK-15 Cells with Deep Sequencing

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    Yuhan Cai

    2015-01-01

    Full Text Available Japanese encephalitis virus (JEV, a mosquito-borne Flavivirus, causes acute viral encephalitis with high morbidity and mortality in humans and animals. MicroRNAs (miRNAs are small noncoding RNAs that are important modulators of the intricate host-pathogen interaction networks. However, our knowledge of the changes that occur in miRNAs in host cells after JEV infection is still limited. To understand the molecular pathogenesis of JEV at the level of posttranscriptional regulation, we used Illumina deep sequencing to sequence two small RNA libraries prepared from PK-15 cells before and after JEV infection. We identified 522 and 427 miRNAs in the infected and uninfected cells, respectively. Overall, 132 miRNAs were expressed significantly differently after challenge with JEV: 78 were upregulated and 54 downregulated. The sequencing results for selected miRNAs were confirmed with RT-qPCR. GO analysis of the host target genes revealed that these dysregulated miRNAs are involved in complex cellular pathways, including the metabolic pathway, inflammatory response and immune response. To our knowledge, this is the first report of the comparative expression of miRNAs in PK-15 cells after JEV infection. Our findings will underpin further studies of miRNAs’ roles in JEV replication and identify potential candidates for antiviral therapies against JEV.

  16. Activated CD56(+) lymphocytes (NK+NKT) mediate immunomodulatory and anti-viral effects during Japanese encephalitis virus infection of dendritic cells in-vitro.

    Science.gov (United States)

    Sooryanarain, Harini; Ayachit, Vijay; Gore, Milind

    2012-10-25

    Japanese encephalitis virus (JEV) remains one of the major causative agents of pediatric encephalitis. Interaction of dendritic cells (DCs) with innate lymphocytes (NK and NKT) represents a crucial event during anti-viral innate immune response. In the current study, we have tried to understand the interaction between JEV, human monocyte derived DCs (MDDCs), and CD56(+) cells (NK+NKT) in-vitro. We have used two JEV strains (i) JE057434 (neurovirulent, wild-type) and (ii) SA14-14-2 (non-neurovirulent, live-attenuated vaccine) to investigate the effect of viral virulence on the functional status of primary human MDDCs. Our preliminary results indicate that replicating JEV induces MDDCs maturation via PI3K and p38 pathways. We also show that the presence of IL2-activated CD56(+) cells impart both immunomodulatory and anti-viral effects on DCs infected with JEV. Mechanistic studies illustrate that, IL2-activated CD56(+) lymphocytes mediated immunomodulation occurs through direct cell-to-cell contact and TNFα, while the anti-viral effect is dependent on direct cell-to-cell contact. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Rapid and simple detection of Japanese encephalitis virus by reverse transcription loop-mediated isothermal amplification combined with a lateral flow dipstick.

    Science.gov (United States)

    Deng, Jieru; Pei, Jingjing; Gou, Hongchao; Ye, Zuodong; Liu, Cuicui; Chen, Jinding

    2015-03-01

    Japanese encephalitis virus (JEV) is a major cause of viral encephalitis in geographical areas, such as Asia and Western Pacific, where it is a threat to human and animal health. To control this disease, it is necessary to develop a rapid, simple, accurate method for diagnosis. In this study, a method based on reverse transcription loop-mediated isothermal amplification (RT-LAMP) coupled with a lateral flow dipstick (LFD) has been developed to detect JEV (JEV RT-LAMP-LFD). The entire assay can be completed within 70 min, and in this study, no false positive results were observed when other pathogens were tested, indicating that the assay is a highly specific method for the detection of JEV. Additionally, the sensitivity of the RT-LAMP-LFD assay for SA14-14-2 strain was 50 pg of RNA, which was similar to that of RT-PCR and RT-LAMP combined with gel electrophoresis, and was 10-fold more sensitive than RT-LAMP combined with calcein. The limit of detection for this assay was 5 pg of RNA. In addition, no false positive results were obtained with 14 serum samples. Our results indicate that this RT-LAMP-LFD assay will be of great value for JEV infection testing due to its rapid and highly specific and sensitive properties. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Herpes simplex encephalitis with thalamic, brainstem and cerebellar involvement.

    Science.gov (United States)

    Garg, Meenal; Kulkarni, Shilpa; Udwadia Hegde, Anaita

    2017-01-01

    Herpes simplex virus encephalitis is a common and treatable cause of acute encephalitis in all age groups. Certain radiological features such as temporal parenchymal involvement facilitate the diagnosis. The use of herpes simplex virus polymerase chain reaction has expanded the clinical and imaging spectrum. We report the case of a young patient who presented with a movement disorder and predominant involvement of thalami, brainstem and cerebellum on magnetic resonance imaging, and was diagnosed with herpes simplex virus encephalitis. Differentiation from Japanese encephalitis may be difficult in these patients, especially in endemic areas, and may necessitate the use of relevant investigations in all patients.

  19. Detection of specific IgG antibodies in blood donors and tick-borne encephalitis virus in ticks within a non-endemic area in southeast Norway.

    Science.gov (United States)

    Larsen, Astri Lervik; Kanestrøm, Anita; Bjørland, Marthe; Andreassen, Ashild; Soleng, Arnulf; Vene, Sirkka; Dudman, Susanne G

    2014-03-01

    Tick-borne encephalitis (TBE) is an emerging tick-borne disease in Europe. In Norway, the first TBE case occurred in 1997, and since then 1-14 cases have been detected annually along the southern coast. No TBE cases have yet been notified from the eastern coastal area. This study was conducted to assess the need for diagnostic tests and vaccine recommendation for this part of Norway. Four hundred and sixty-one blood donors living in the county of Østfold were enrolled. After informed consent was obtained, the participants submitted a blood sample and filled out a questionnaire regarding tick bites, outdoor activities, and Flavivirus vaccines and diseases. Ixodes ricinus ticks were collected from the immediate vicinity and were examined in pools of 10 for TBE virus. Eight human samples were TBE virus IgG-positive by ELISA and 5 of these samples were confirmed positive by neutralization test. Excluding the 2 samples from participants who had reported previous TBE vaccination, this shows a seroprevalence among blood donors of 0.65%. The existence of TBEV in the region was verified in nymphs of Ixodes ricinus by a prevalence of 0.14%. The seroprevalence of TBE virus IgG and the TBE virus detected in ticks, indicate that TBE cases could occasionally occur in the area. The results should be made available to health care personnel to raise awareness for preventative measures.

  20. Equine Vaccines: How, When and Why? Report of the Vaccinology Session, French Equine Veterinarians Association, 2016, Reims

    Directory of Open Access Journals (Sweden)

    Romain Paillot

    2017-12-01

    Full Text Available To date, vaccination is one of the most efficient methods of prevention against equine infectious diseases. The vaccinology session, which was organised during the annual meeting of the French Equine Veterinarians Association (AVEF at Reims (France in 2016, aimed to approach three subjects of importance for the equine industry. Vaccination against three major equine diseases were used as examples: equine influenza (equine influenza virus, rhinopneumonitis (equine herpes virus 1/4, and tetanus (Clostridium tetani neuro-toxin. (1 Emergency vaccination: while it has been very successful to reduce the impact of equine influenza epizooties and it is also recommended for tetanus in case of surgery and accident, the benefit of emergency vaccination against equine herpes virus 1/4 remains arguable; (2 Compatibility of equine vaccines from different brands: despite being a frequent concerns for equine veterinarians, little information is available about the compatibility of equine vaccines from different commercial origins. The consequence of mixing different equine vaccines targeting the same disease is believed to be limited but scientific evidences are sparse; and, (3 Laps vaccination and vaccine shortage: they could have serious consequences in terms of protection and their impact should be evaluated on a case by case basis, taking into account the risk of contact with the pathogen and the effect on herd immunity.

  1. Travel-acquired Japanese encephalitis and vaccination considerations.

    Science.gov (United States)

    Pavli, Androula; Maltezou, Helena C

    2015-09-27

    Japanese encephalitis (JE) is a serious arboviral disease caused by a virus of the genus Flavivirus. Japanese encephalitis is the most common vaccine-preventable virus causing encephalitis in Asia, affecting more than 50,000 persons and leading to 15,000 fatalities per year in endemic countries. For most travelers to Asia, the risk of Japanese encephalitis infection is extremely low and depends on destination, duration of travel, season, and activities. This article reviews travel-acquired Japanese encephalitis with a focus on epidemiology and prevention in the light of the newly available options for active immunization against Japanese encephalitis which have become available, and of the increasing popularity of travels to Japanese encephalitis endemic countries.

  2. Development and evaluation of a reverse transcription-insulated isothermal polymerase chain reaction (RT-iiPCR) assay for detection of equine arteritis virus in equine semen and tissue samples using the POCKIT™ system.

    Science.gov (United States)

    Carossino, Mariano; Lee, Pei-Yu A; Nam, Bora; Skillman, Ashley; Shuck, Kathleen M; Timoney, Peter J; Tsai, Yun-Long; Ma, Li-Juan; Chang, Hsiao-Fen G; Wang, Hwa-Tang T; Balasuriya, Udeni B R

    2016-08-01

    Equine arteritis virus (EAV) is the causative agent of equine viral arteritis (EVA), a respiratory and reproductive disease of horses. Most importantly, EAV induces abortion in pregnant mares and can establish persistent infection in up to 10-70% of the infected stallions, which will continue to shed the virus in their semen. The objective of this study was to develop and evaluate a reverse transcription insulated isothermal polymerase chain reaction (RT-iiPCR) for the detection of EAV in semen and tissue samples. The newly developed assay had a limit of detection of 10 RNA copies and a 10-fold higher sensitivity than a previously described real-time RT-PCR (RT-qPCR). Evaluation of 125 semen samples revealed a sensitivity and specificity of 98.46% and 100.00%, respectively for the RT-qPCR assay, and 100.00% and 98.33%, respectively for the RT-iiPCR assay. Both assays had the same accuracy (99.2%, k=0.98) compared to virus isolation. Corresponding values derived from testing various tissue samples (n=122) collected from aborted fetuses, foals, and EAV carrier stallions are as follows: relative sensitivity, specificity, and accuracy of 88.14%, 96.83%, and 92.62% (k=0.85), respectively for the RT-qPCR assay, and 98.31%, 92.06%, and 95.08% (k=0.90), respectively for the RT-iiPCR assay. These results indicate that RT-iiPCR is a sensitive, specific, and a robust test enabling detection of EAV in semen and tissue samples with very considerable accuracy. Even though the RT-qPCR assay showed a sensitivity and specificity equal to virus isolation for semen samples, its diagnostic performance was somewhat limited for tissue samples. Thus, this new RT-iiPCR could be considered as an alternative tool in the implementation of EAV control and prevention strategies. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Immunogenicity of a Japanese encephalitis chimeric virus vaccine as a booster dose after primary vaccination with SA14-14-2 vaccine in Thai children.

    Science.gov (United States)

    Janewongwirot, Pakpoom; Puthanakit, Thanyawee; Anugulruengkitt, Suvaporn; Jantarabenjakul, Watsamon; Phasomsap, Chayapa; Chumket, Sompong; Yoksan, Sutee; Pancharoen, Chitsanu

    2016-10-17

    Japanese Encephalitis chimeric virus vaccine (JE-CV) and SA14-14-2 vaccine are live-attenuated JE vaccines produced from the same virus strain. Data on interchangeability is limited. To evaluate the immunogenicity and safety of JE-CV booster after primary vaccination with SA14-14-2 vaccine. This study was an open-label clinical trial in Thai children who had received a primary SA14-14-2 vaccination at 12-24monthsbefore enrollment (ClinicalTrials.gov NCT02602652). JE-CV was administered. A 50% plaque reduction neutralization test (PRNT 50 ) against three virus strains; JE-CV, SA-14-14-2andwild-type JE virus was measured before and 28-days post vaccination. The laboratory was performed at PRNT 50 titers ⩾10 (1/dil) were considered seroprotective against JE. Geometric mean titer (GMT) of PRNT 50 was calculated. Adverse events were observed for 28days. From March 2014 to June 2015, 50 children (64% male) were enrolled. Mean age and duration after primary vaccination was 26.9 (SD 4.6) and 12.8 (SD 2.7) months, respectively. The proportion of participants who had PRNT 50 pre and post-booster vaccination were 92% and 96% against JE-CV virus, 56% and 98% against SA-14-14-2 strain and 70% and 98% against wild-type JE virus, respectively. Solicited injection site reactions including erythema, pain and swelling occurred in 18%, 10% and 4% of subjects, respectively. Four children (8%) had fever (⩾37.7Celsius). Eight children (16%) had adverse events, which were not related to the vaccine. AJE-CV booster dose is highly immunogenic and safe among children who previously received SA14-14-2 vaccine. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Multicenter Evaluation of BioFire FilmArray Meningitis/Encephalitis Panel for Detection of Bacteria, Viruses, and Yeast in Cerebrospinal Fluid Specimens.

    Science.gov (United States)

    Leber, Amy L; Everhart, Kathy; Balada-Llasat, Joan-Miquel; Cullison, Jillian; Daly, Judy; Holt, Sarah; Lephart, Paul; Salimnia, Hossein; Schreckenberger, Paul C; DesJarlais, Sharon; Reed, Sharon L; Chapin, Kimberle C; LeBlanc, Lindsay; Johnson, J Kristie; Soliven, Nicole L; Carroll, Karen C; Miller, Jo-Anne; Dien Bard, Jennifer; Mestas, Javier; Bankowski, Matthew; Enomoto, Tori; Hemmert, Andrew C; Bourzac, Kevin M

    2016-09-01

    Rapid diagnosis and treatment of infectious meningitis and encephalitis are critical to minimize morbidity and mortality. Comprehensive testing of cerebrospinal fluid (CSF) often includes Gram stain, culture, antigen detection, and molecular methods, paired with chemical and cellular analyses. These methods may lack sensitivity or specificity, can take several days, and require significant volume for complete analysis. The FilmArray Meningitis/Encephalitis (ME) Panel is a multiplexed in vitro diagnostic test for the simultaneous, rapid (∼1-h) detection of 14 pathogens directly from CSF specimens: Escherichia coli K1, Haemophilus influenzae, Listeria monocytogenes, Neisseria meningitidis, Streptococcus pneumoniae, Streptococcus agalactiae, cytomegalovirus, enterovirus, herpes simplex virus 1 and 2, human herpesvirus 6, human parechovirus, varicella-zoster virus, and Cryptococcus neoformans/Cryptococcus gattii We describe a multicenter evaluation of 1,560 prospectively collected CSF specimens with performance compared to culture (bacterial analytes) and PCR (all other analytes). The FilmArray ME Panel demonstrated a sensitivity or positive percentage of agreement of 100% for 9 of 14 analytes. Enterovirus and human herpesvirus type 6 had agreements of 95.7% and 85.7%, and L. monocytogenes and N. meningitidis were not observed in the study. For S. agalactiae, there was a single false-positive and false-negative result each, for a sensitivity and specificity of 0 and 99.9%, respectively. The specificity or negative percentage of agreement was 99.2% or greater for all other analytes. The FilmArray ME Panel is a sensitive and specific test to aid in diagnosis of ME. With use of this comprehensive and rapid test, improved patient outcomes and antimicrobial stewardship are anticipated. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  5. Encefalitis aguda: Manifestaciones neuropsiquiátricas como expresión de infección por virus de influenza Acute encephalitis: Neuropsychiatric manifestations as expression of influenza virus infection

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    Noris Moreno-Flagge

    2009-01-01

    Full Text Available El objetivo fue revisar la encefalitis en niños y adolescentes, su etiología, manifestaciones clínicas, fisiopatología, métodos diagnósticos y tratamiento, enfatizando las manifestaciones neuropsiquiátricas de la encefalitis durante una epidemia de influenza. La encefalitis se considera una inflamación del sistema nervioso central (SNC que compromete el cerebro. Se manifiesta usualmente por cefaleas, fiebre y trastorno del estado de conciencia. Puede además manifestarse por convulsiones, cambios en la personalidad y manifestaciones obsesivas (síntomas neuropsiquiátricos. Las manifestaciones dependerán del tipo de virus y las células afectadas. La encefalitis puede ser causada por una gran variedad de agentes infecciosos incluyendo virus, bacterias, hongos y parásitos. Causas virales de encefalitis incluyen herpesvirus, arbovirus, rabia y enterovirus. Casos establecidos de bacterias incluyen Borrelia burgdorferi y rickettsia y el Mycoplasma neumoniae, al cual se atribuyen varios casos de encefalitis. Otros agentes como el hongo Coccidioides immitis e Histoplasma capsulatum pueden también generarla. Más de 100 agentes se han asociado a encefalitis. El diagnóstico de encefalitis constituye un reto para el clínico, y su etiología infecciosa usualmente se identifica entre el 40% al 70% de casos. El diagnóstico se hace con absoluta certeza sólo con una biopsia cerebral. La epidemiología depende de ciertos factores como la edad, la localización geográfica, la época del año, las condiciones climáticas y la inmunocompetencia del huésped. El tratamiento temprano puede disminuir el riesgo de muerte y las secuelas. Describimos cuatro pacientes con encefalitis y manifestaciones neuropsiquiátricas durante una epidemia de influenza, con el fin de alertar sobre esta asociación.The aim is to review the encephalitis in infants and adolescents as well as its etiology, clinical manifestation, epidemiology, physiopathology, diagnostic

  6. Inhibition of ERK and proliferation in NK cell lines by soluble HLA-E released from Japanese encephalitis virus infected cells.

    Science.gov (United States)

    Shwetank; Date, Onkar Sanjay; Carbone, Ennio; Manjunath, Ramanathapuram

    2014-11-01

    Productive infection of human endothelial cells with Japanese encephalitis virus (JEV), a single stranded RNA virus induces shedding of sHLA-E. We show here that sHLA-E that is released upon infection with this flavivirus can inhibit IL-2 and PMA mediated ERK 1/2 phosphorylation in two NK cell lines, Nishi and NKL. Virus infected or IFN-γ treated cell culture supernatants containing sHLA-E were found to partially inhibit IL-2 mediated induction of CD25 molecules on NKL cells. It was also found that sHLA-E could inhibit IL-2 induced [(3)H]-thymidine incorporation suggesting that, similar to cell surface expressed HLA-E, sHLA-E could also inhibit NK cell responses. Hence JEV-induced shedding of sHLA-E needs further investigation to better understand immune responses in JEV infections since it may have a role in viral evasion of NK cell responses. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. A single mutation in the Japanese encephalitis virus E protein (S123R) increases its growth rate in mouse neuroblastoma cells and its pathogenicity in mice.

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    Tajima, Shigeru; Nerome, Reiko; Nukui, Yoko; Kato, Fumihiro; Takasaki, Tomohiko; Kurane, Ichiro

    2010-01-20

    We previously reported that the Japanese encephalitis virus (JEV) strain Mie/41/2002 has weak pathogenicity compared with the laboratory strain Beijing-1. To identify the determinants of its growth nature and pathogenicity, we produced intertypic viruses, rJEV(EB1-M41), rJEV(nEB1-M41) and rJEV(cEB1-M41), which contained the entire, the N-terminal, and the C-terminal half, respectively, of the Beijing-1 E region in the Mie/41/2002 background. The growth of rJEV(EB1-M41) in mouse neuroblastoma N18 cells and virulence in mice were similar to those of Beijing-1. rJEV(nEB1-M41) propagated in N18 cells to the same extent as did Beijing-1. Furthermore, we produced mutant viruses with single amino acid substitutions in the N-terminal half of the Mie/41/2002 E region. A Ser-123-Arg mutation in the Mie/41/2002 E protein exhibited significantly increased growth rate in N18 cells and virulence in mice. These results indicate that the position 123 in the E protein is responsible for determining the growth properties and pathogenicity of JEV.

  8. In vitro and in vivo characterization of chimeric duck Tembusu virus based on Japanese encephalitis live vaccine strain SA14-14-2.

    Science.gov (United States)

    Wang, Hong-Jiang; Liu, Long; Li, Xiao-Feng; Ye, Qing; Deng, Yong-Qiang; Qin, E-De; Qin, Cheng-Feng

    2016-07-01

    Duck Tembusu virus (DTMUV), a newly identified flavivirus, has rapidly spread to China, Malaysia and Thailand. The potential threats to public health have been well-highlighted; however its virulence and pathogenesis remain largely unknown. Here, by using reverse genetics, a recombinant chimeric DTMUV based on Japanese encephalitis live vaccine strain SA14-14-2 was obtained by substituting the corresponding prM and E genes (named ChinDTMUV). In vitro characterization demonstrated that ChinDTMUV replicated efficiently in mammalian cells with small-plaque phenotype in comparison with its parental viruses. Mouse tests showed ChinDTMUV exhibited avirulent phenotype in terms of neuroinvasiveness, while it retained neurovirulence from its parental virus DTMUV. Furthermore, immunization with ChinDTMUV was evidenced to elicit robust IgG and neutralizing antibody responses in mice. Overall, we successfully developed a viable chimeric DTMUV, and these results provide a useful platform for further investigation of the pathogenesis of DTMUV and development of a live attenuated DTMUV vaccine candidate.

  9. Equine influenza: An overview

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    S. P. Waghmare

    2010-08-01

    Full Text Available Equine influenza virus is a leading cause of respiratory disease in the horses. The disease is the OIE listed disease of equines, ponies, mules and donkeys and spreads very fast. The sporadic outbreaks of the disease have occurred all over the country. Many cases have been reported in Delhi, Meerut, Saharanpur, Jaipur, Hisar, Calcutta, Ahmedabad. Nearly all the horses at Matheran (Hill station were infected with influenza. The disease has spread like wildfire at the stables of Royal Western India Turf Club (RWITC at Pune and suspended the Mumbai racing season for prolonged period of time resulting in marked economic losses. After affecting racing in Mumbai, Calcutta and New Delhi, the dreaded equine influenza has spread to Karnataka and Mysore. An outbreak of disease has marred the racing season across the country. The disease was first detected in Jammu & Kashmir before entering the central region Horses at the army polo clubs and Delhi equestrian center were also affected. As per the recent survey conducted by the army across India, it has been found that 5400 horses are infected so far, especially thoroughbred most severely. Nearly, 95 % of horses on a major farm in India are suspected of suffering from equine influenza. The government also banned inter-state movement of horses for three months to contain the disease. [Vet World 2010; 3(4.000: 194-197

  10. The Molecular Epidemiology and Evolution of Murray Valley Encephalitis Virus: Recent Emergence of Distinct Sub-lineages of the Dominant Genotype 1.

    Directory of Open Access Journals (Sweden)

    David T Williams

    2015-11-01

    Full Text Available Recent increased activity of the mosquito-borne Murray Valley encephalitis virus (MVEV in Australia has renewed concerns regarding its potential to spread and cause disease.To better understand the genetic relationships between earlier and more recent circulating strains, patterns of virus movement, as well as the molecular basis of MVEV evolution, complete pre-membrane (prM and Envelope (Env genes were sequenced from sixty-six MVEV strains from different regions of the Australasian region, isolated over a sixty year period (1951-2011. Phylogenetic analyses indicated that, of the four recognized genotypes, only G1 and G2 are contemporary. G1 viruses were dominant over the sampling period and found across the known geographic range of MVEV. Two distinct sub-lineages of G1 were observed (1A and 1B. Although G1B strains have been isolated from across mainland Australia, Australian G1A strains have not been detected outside northwest Australia. Similarly, G2 is comprised of only Western Australian isolates from mosquitoes, suggesting G1B and G2 viruses have geographic or ecological restrictions. No evidence of recombination was found and a single amino acid substitution in the Env protein (S332G was found to be under positive selection, while several others were found to be under directional evolution. Evolutionary analyses indicated that extant genotypes of MVEV began to diverge from a common ancestor approximately 200 years ago. G2 was the first genotype to diverge, followed by G3 and G4, and finally G1, from which subtypes G1A and G1B diverged between 1964 and 1994.The results of this study provides new insights into the genetic diversity and evolution of MVEV. The demonstration of co-circulation of all contemporary genetic lineages of MVEV in northwestern Australia, supports the contention that this region is the enzootic focus for this virus.

  11. Anti Japanese encephalitis virus IgM positivity among patients with acute encephalitic syndrome admitted to different hospitals from all over Nepal.

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    Bhattarai, Anupama; Pant, Narayan Dutt; Nepal, Krishus; Adhikari, Sailaja; Sharma, Mukunda; Parajuli, Pramila

    2017-01-01

    The Japanese encephalitis virus (JEV) infection is one of the major public health problems in Nepal because of its increasing disease morbidity and mortality. The main purpose of this study was to determine the anti-JEV IgM positivity among acute encephalitis syndromic cases from all over Nepal. The present study was conducted at National Public Health Laboratory, Kathmandu, Nepal from April 2015 to October 2015. A total of 671 (418 CSF and 253 serum) samples were collected from 625 patients with acute encephalitic syndrome, admitted to different hospitals from all over Nepal. IgM antibody capture enzyme linked immunosorbent assay (ELISA) was used for the detection of anti-JEV IgM positive cases. The rate of anti-JEV IgM positivity was found to be 21.12%. The majority of positive cases (50%) were from the age group below 15 years, with the highest numbers of cases occurring in September (55.30%). Among all the anti-JEV IgM positive cases, higher numbers of cases were males. Geographically, the highest numbers of anti-JEV IgM positive cases were recorded from Terai region. Similarly, largest numbers of anti-JEV IgM positive cases were reported from Kailai district followed by those from Kanchanpur. However, anti-JEV IgM positive cases were also reported from hill districts. Continuation of active surveillance and vector control measures, proper management of diagnostic facilities and expanded program of immunization in JE endemic ar