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Sample records for choriomeningitis virus infection

  1. Virus elimination in acute lymphocytic choriomeningitis virus infection. Correlation with virus-specific delayed-type hypersensitivity rather than cytotoxicity

    DEFF Research Database (Denmark)

    Thomsen, Allan Randrup; Volkert, M; Bro-Jørgensen, K

    1983-01-01

    The immunological effector mechanism responsible for the elimination of virus in murine acute non-fatal extracranial lymphocytic choriomeningitis virus infection was studied. In this infection virus clearance is generally regarded as the result of a direct action of virus-specific cytotoxic T cells...

  2. Fatal meningitis following lymphocytic choriomeningitis virus infection reflects delayed-type hypersensitivity rather than cytotoxicity

    DEFF Research Database (Denmark)

    Thomsen, Allan Randrup; Bro-Jørgensen, K; Volkert, M

    1983-01-01

    Fatal meningitis following intracerebral inoculation of lymphocytic choriomeningitis virus (LCMV) reflects an immunopathological lesion believed to be mediated by cytotoxic T cells. The results presented here demonstrate that pretreatment with cyclophosphamide (Cy; 150 mg/kg body weight) 2 days...... before intracerebral infection significantly reduced the lethality of the infection. However, this treatment did not impair the antiviral cytotoxic response as measured in the spleen. On the other hand, virus-specific delayed-type hypersensitivity (DTH) was significantly reduced. This reduction seems...... not solely represent T-cell-mediated cytotoxicity in vivo but that a fatal outcome of the infection critically involves not only effector T cells but also ancillary cells....

  3. Serological Evidence of Lymphocytic Choriomeningitis Virus Infection in Japan

    OpenAIRE

    SATO, HIROSHI

    1989-01-01

    Indirect fluorescent antibody method was applied for a detection of lymphocytic choriomenigitis virus (LCMV) antibody in colonies of laboratory animals in Japan. The results showed that the antibody exist in SPF mice (3/152,2.0%) and conventional mice (30/539, 5.6%) with the titers ranging from 1: 10 to 1: 160. The antibody was also detected in 2.2% (2/89) of Syrian golden hamsters, and 2.9% (2/68) of Apodemus agrarius, 21.4% (3/14) of Japanese harvest mice which have been maintained as labor...

  4. Congenital viral infections of the brain: lessons learned from lymphocytic choriomeningitis virus in the neonatal rat.

    Directory of Open Access Journals (Sweden)

    Daniel J Bonthius

    2007-11-01

    Full Text Available The fetal brain is highly vulnerable to teratogens, including many infectious agents. As a consequence of prenatal infection, many children suffer severe and permanent brain injury and dysfunction. Because most animal models of congenital brain infection do not strongly mirror human disease, the models are highly limited in their abilities to shed light on the pathogenesis of these diseases. The animal model for congenital lymphocytic choriomeningitis virus (LCMV infection, however, does not suffer from this limitation. LCMV is a well-known human pathogen. When the infection occurs during pregnancy, the virus can infect the fetus, and the developing brain is particularly vulnerable. Children with congenital LCMV infection often have substantial neurological deficits. The neonatal rat inoculated with LCMV is a superb model system of human congenital LCMV infection. Virtually all of the neuropathologic changes observed in humans congenitally infected with LCMV, including microencephaly, encephalomalacia, chorioretinitis, porencephalic cysts, neuronal migration disturbances, periventricular infection, and cerebellar hypoplasia, are reproduced in the rat model. Within the developing rat brain, LCMV selectively targets mitotically active neuronal precursors. Thus, the targets of infection and sites of pathology depend on host age at the time of infection. The rat model has further shown that the pathogenic changes induced by LCMV infection are both virus-mediated and immune-mediated. Furthermore, different brain regions simultaneously infected with LCMV can undergo widely different pathologic changes, reflecting different brain region-virus-immune system interactions. Because the neonatal rat inoculated with LCMV so faithfully reproduces the diverse neuropathology observed in the human counterpart, the rat model system is a highly valuable tool for the study of congenital LCMV infection and of all prenatal brain infections In addition, because LCMV

  5. Lymphocytic choriomeningitis virus (LCMV) infection of macaques: a model for Lassa fever

    Science.gov (United States)

    Zapata, Juan C.; Pauza, C. David; Djavani, Mahmoud M.; Rodas, Juan D.; Moshkoff, Dmitry; Bryant, Joseph; Ateh, Eugene; Garcia, Cybele; Lukashevich, Igor S.; Salvato, Maria S.

    2011-01-01

    Arenaviruses such as Lassa fever virus (LASV) and lymphocytic choriomeningitis virus (LCMV) are benign in their natural reservoir hosts, and can occasionally cause severe viral hemorrhagic fever (VHF) in non-human primates and in human beings. LCMV is considerably more benign for human beings than Lassa virus, however certain strains, like the LCMV-WE strain, can cause severe disease when the virus is delivered as a high-dose inoculum. Here we describe a rhesus macaque model for Lassa fever that employs a virulent strain of LCMV. Since LASV must be studied within Biosafety Level-4 (BSL-4) facilities, the LCMV-infected macaque model has the advantage that it can be used at BSL-3. LCMV-induced disease is rarely as severe as other VHF, but it is similar in cases where vascular leakage leads to lethal systemic failure. The LCMV-infected macaque has been valuable for describing the course of disease with differing viral strains, doses and routes of infection. By monitoring system-wide changes in physiology and gene expression in a controlled experimental setting, it is possible to identify events that are pathognomonic for developing VHF and potential treatment targets. PMID:21820469

  6. Lymphocytic choriomeningitis virus (LCMV) infection of macaques: a model for Lassa fever.

    Science.gov (United States)

    Zapata, Juan C; Pauza, C David; Djavani, Mahmoud M; Rodas, Juan D; Moshkoff, Dmitry; Bryant, Joseph; Ateh, Eugene; Garcia, Cybele; Lukashevich, Igor S; Salvato, Maria S

    2011-11-01

    Arenaviruses such as Lassa fever virus (LASV) and lymphocytic choriomeningitis virus (LCMV) are benign in their natural reservoir hosts, and can occasionally cause severe viral hemorrhagic fever (VHF) in non-human primates and in human beings. LCMV is considerably more benign for human beings than Lassa virus, however certain strains, like the LCMV-WE strain, can cause severe disease when the virus is delivered as a high-dose inoculum. Here we describe a rhesus macaque model for Lassa fever that employs a virulent strain of LCMV. Since LASV must be studied within Biosafety Level-4 (BSL-4) facilities, the LCMV-infected macaque model has the advantage that it can be used at BSL-3. LCMV-induced disease is rarely as severe as other VHF, but it is similar in cases where vascular leakage leads to lethal systemic failure. The LCMV-infected macaque has been valuable for describing the course of disease with differing viral strains, doses and routes of infection. By monitoring system-wide changes in physiology and gene expression in a controlled experimental setting, it is possible to identify events that are pathognomonic for developing VHF and potential treatment targets.

  7. Compromised virus control and augmented perforin-mediated immunopathology in IFN-gamma-deficient mice infected with lymphocytic choriomeningitis virus

    DEFF Research Database (Denmark)

    Nansen, A; Jensen, Teis; Christensen, Jan Pravsgaard;

    1999-01-01

    To define the role of IFN-gamma in the control of acute infection with a noncytopathogenic virus, mice with targeted defects of the genes encoding IFN-gamma, perforin, or both were infected i.v. with two strains of lymphocytic choriomeningitis virus differing markedly in their capacity to spread...... in wild-type mice. Our results reveal that IFN-gamma is pivotal to T cell-mediated control of a rapidly invasive stain, whereas it is less important in the acute elimination of a slowly invasive strain. Moreover, the majority of mice infected with the rapidly invasive strain succumb to a wasting syndrome...... controlled infection and limited tissue damage. Thus, the presence or absence of IFN-gamma determines whether CTLs will clear infection with this noncytopathogenic virus or induce severe immunopathology....

  8. Vaccination against lymphocytic choriomeningitis virus infection in MHC class II-deficient mice

    DEFF Research Database (Denmark)

    Holst, Peter Johannes; Christensen, Jan Pravsgaard; Thomsen, Allan Randrup

    2011-01-01

    response could be elicited in MHC class II-deficient mice by vaccination with adenovirus encoding lymphocytic choriomeningitis virus (LCMV) glycoprotein tethered to MHC class II-associated invariant chain. Moreover, the response induced conferred significant cytolytic CD8(+) T cell-mediated protection...... against challenge with a high dose of the invasive clone 13 strain of LCMV. In contrast, vaccination with adenovirus encoding unlinked LCMV glycoprotein induced weak virus control in the absence of CD4(+) T cells, and mice may die of increased immunopathology associated with incomplete protection. Acute...

  9. Circulating natural killer and γδ T cells decrease soon after infection of rhesus macaques with lymphocytic choriomeningitis virus

    Directory of Open Access Journals (Sweden)

    Juan D Rodas

    2009-07-01

    Full Text Available Rhesus macaques infected with the WE strain of lymphocytic choriomeningitis virus (LCMV-WE serve as a model for human infection with Lassa fever virus. To identify the earliest events of acute infection, rhesus macaques were monitored immediately after lethal infection for changes in peripheral blood mononuclear cells (PBMCs. Changes in CD3, CD4, CD8 and CD20 subsets did not vary outside the normal fluctuations of these blood cell populations; however, natural killer (NK and γδ T cells increased slightly on day 1 and then decreased significantly after two days. The NK subsets responsible for the decrease were primarily CD3-CD8+ or CD3-CD16+ and not the NKT (primarily CD3+CD56+ subset. Macaques infected with a non-virulent arenavirus, LCMV-Armstrong, showed a similar drop in circulating NK and γδ T cells, indicating that this is not a pathogenic event. V³9 T cells, representing the majority of circulating γδ T cells in rhesus macaques, displayed significant apoptosis when incubated with LCMV in cell culture; however, the low amount of cell death for virus-co-cultured NK cells was insufficient to account for the observed disappearance of this subset. Our observations in primates are similar to those seen in LCMV-infected mice, where decreased circulating NK cells were attributed to margination and cell death. Thus, the disappearance of these cells during acute hemorrhagic fever in rhesus macaques may be a cytokine-induced lymphopenia common to many virus infections.

  10. Studies on the role of mononuclear phagocytes in resistance to acute lymphocytic choriomeningitis virus infection

    DEFF Research Database (Denmark)

    Thomsen, Allan Randrup; Volkert, M

    1983-01-01

    difficulty in eliminating. Adoptive transfer experiments with pre-irradiated recipients showed that T-cell-dependent virus clearance required interaction between donor-derived primary immune spleen cells and radiosensitive host cells. T cells did not seem to constitute the radiosensitive host component...

  11. [Incidence and features of neuroinfections induced by lymphocytic choriomeningitis virus].

    Science.gov (United States)

    Dekonenko, E P; Tkachenko, E A; Umanskiĭ, K G; Ivanov, A P; Rezapkin, G V

    1986-01-01

    A follow-up examination of blood sera and cerebrospinal fluid was carried out in 413 patients with various neuroinfections and related diseases. The modern immunological methods were employed: the complement fixation test, the fluorescent antibody test as well as immuno-enzymic and radioimmunoassays. It was established that 8.5% of serous meningitides and 12% of encephalitides were induced by lymphocytic choriomeningitis (LCM) virus. The verified diseases were subjected to a clinical analysis. It is emphasized that the immunological examination of the cerebrospinal fluid in patients with LCM infection contributes to a more detailed study of the pathogenesis of the disease.

  12. Cell entry of lymphocytic choriomeningitis virus is restricted in myotubes.

    Science.gov (United States)

    Iwasaki, Masaharu; Urata, Shuzo; Cho, Yoshitake; Ngo, Nhi; de la Torre, Juan C

    2014-06-01

    In mice persistently infected since birth with the prototypic arenavirus lymphocytic choriomeningitis viurs, viral antigen and RNA are readily detected in most organs and cell types but remarkably absent in skeletal muscle. Here we report that mouse C2C12 myoblasts that are readily infected by LCMV, become highly refractory to LCMV infection upon their differentiation into myotubes. Myotube's resistance to LCMV was not due to an intracellular restriction of virus replication but rather an impaired cell entry mediated by the LCMV surface glycoprotein. Our findings provide an explanation for the observation that in LCMV carrier mice myotubes, which are constantly exposed to blood-containing virus, remain free of viral antigen and RNA despite myotubes express high levels of the LCMV receptor alpha dystroglycan and do not pose an intracellular blockade to LCMV multiplication.

  13. Agonistic anti-CD40 antibody profoundly suppresses the immune response to infection with lymphocytic choriomeningitis virus

    DEFF Research Database (Denmark)

    Bartholdy, Christina; Kauffmann, Susanne Ørding; Christensen, Jan Pravsgaard;

    2007-01-01

    also collapsed prematurely, and virus clearance was delayed. Additional analysis revealed that, following anti-CD40 treatment, the virus-specific CD8 T cells initially proliferated normally, but an increased cell loss compared with that in untreated mice was observed. The anti-CD40-induced abortion...... of virus-specific CD8 T cells during LCMV infection was IL-12 independent, but depended partly on Fas expression. Notably, similar anti-CD40 treatment of vesicular stomatitis virus-infected mice resulted in an improved antiviral CD8 T cell response, demonstrating that the effect of anti-CD40 treatment...

  14. Mice deficient in STAT1 but not STAT2 or IRF9 develop a lethal CD4+ T-cell-mediated disease following infection with lymphocytic choriomeningitis virus

    NARCIS (Netherlands)

    Hofer, M.J.; Li, W.; Manders, P.; Terry, R.; Lim, S.L.; King, N.J.; Campbell, I.L.

    2012-01-01

    Interferon (IFN) signaling is crucial for antiviral immunity. While type I IFN signaling is mediated by STAT1, STAT2, and IRF9, type II IFN signaling requires only STAT1. Here, we studied the roles of these signaling factors in the host response to systemic infection with lymphocytic choriomeningiti

  15. Delayed contraction of the CD8+ T cell response toward lymphocytic choriomeningitis virus infection in mice lacking serglycin

    DEFF Research Database (Denmark)

    Grujic, Mirjana; Christensen, Jan P; Sørensen, Maria R

    2008-01-01

    We previously reported that the lack of serglycin proteoglycan affects secretory granule morphology and granzyme B (GrB) storage in in vitro generated CTLs. In this study, the role of serglycin during viral infection was studied by infecting wild-type (wt) mice and serglycin-deficient (SG...... response was also seen after infection with vesicular stomatitis virus. BrdU labeling of cells in vivo revealed that the delayed contraction was associated with sustained proliferation of Ag-specific CD8(+) T cells in SG(-/-) mice. Moreover, wt LCMV-specific CD8(+) T cells from TCR318 transgenic mice...... expanded much more extensively in virus-infected SG(-/-) mice than in matched wt mice, indicating that the delayed contraction represents a T cell extrinsic phenomenon. In summary, the present report points to a novel, previously unrecognized role for serglycin proteoglycan in regulating the kinetics...

  16. Persistent virus infection despite chronic cytotoxic T-lymphocyte activation in gamma interferon-deficient mice infected with lymphocytic choriomeningitis virus

    DEFF Research Database (Denmark)

    Bartholdy, C; Christensen, Jan Pravsgaard; Wodarz, D;

    2000-01-01

    ). While wild-type mice rapidly cleared the infection, IFN-gamma -/- mice became chronically infected. Virus persistence in the latter mice did not reflect failure to generate cytotoxic T-lymphocyte (CTL) effectors, as an unimpaired primary CTL response was observed. Furthermore, while ex vivo CTL activity...

  17. Lymphocytic choriomeningitis virus infection is associated with long-standing perturbation of LFA-1 expression on CD8+ T cells

    DEFF Research Database (Denmark)

    Andersson, E C; Christensen, Jan Pravsgaard; Scheynius, A;

    1995-01-01

    belonged to the CD8+LFA-1hi subset and, correspondingly, the ligand ICAM-1 was found to be up-regulated on endothelial cells in the inflamed meninges. Preincubation of LCMV-primed donor splenocytes with anti-LFA-1 markedly inhibited the transfer of virus-specific delayed-type hypersensitivity to naive...... recipients. Together, these findings indicate that up-regulation of LFA-1 expression is a critical factor involved in directing activated CD8+ T cells to sites of viral infection....

  18. Concanavalin A-induced activation of lymphocytic choriomeningitis virus memory lymphocytes into specifically cytotoxic T cells

    DEFF Research Database (Denmark)

    Marker, O; Thomsen, Allan Randrup; Andersen, G T

    1977-01-01

    When spleen cells, which have been primed to Lymphocytic Choriomeningitis (LCM) virus during a primary infection several months previously, are stimulated in vitro with Con A. highly specific secondary cytotoxic effector cells are generated. The degree of cytotoxicity revealed by such Con A......-stimulated cells is higher than that of non-incubated spleen cells harvested nine days following the primary infection, and the effect is totally inhibited by anti-theta serum plus complement treatment of the effector cells immediately before the cytotoxic test....

  19. High-dose survival in the lymphocytic choriomeningitis virus infection is accompanied by suppressed DTH but unaffected T-cell cytotoxicity

    DEFF Research Database (Denmark)

    Marker, O; Thomsen, Allan Randrup; Volkert, M

    1985-01-01

    in mice infected with these doses of virus. In the high-dose mice we found generally higher organ virus titres and serum interferon titres than in the low-dose mice. Since we could demonstrate that virus-specific T-cell cytotoxicity in spleen, peripheral blood, and meningeal exudate was similar after...... intracerebral infection with large and small virus doses, and since the LCMV infection in the brain qualitatively and quantitatively was independent of the size of virus inoculum, the explanation for the survival of the high-dose animals is obviously not lack of possibilities for interaction between cytotoxic T...... after infection with high doses of virus suggest a central role for Td function also in virus clearance. Finally, our results indicate the existence of two subsets of K,D region-restricted T cells, one mediating cytotoxicity and the other mediating DTH. This possibility is discussed....

  20. MHC and non-MHC genes regulate elimination of lymphocytic choriomeningitis virus and antiviral cytotoxic T lymphocyte and delayed-type hypersensitivity mediating T lymphocyte activity in parallel

    DEFF Research Database (Denmark)

    Thomsen, Allan Randrup; Marker, O

    1989-01-01

    The course of systemic infection with lymphocytic choriomeningitis virus was studied in mouse strains differing in the MHC or non-MHC background. Virus clearance rates differed significantly between H-2 identical strains as well as between congenic strains differing in the H-2L subregion, indicat......The course of systemic infection with lymphocytic choriomeningitis virus was studied in mouse strains differing in the MHC or non-MHC background. Virus clearance rates differed significantly between H-2 identical strains as well as between congenic strains differing in the H-2L subregion...

  1. The Lymphocytic Choriomeningitis Virus Matrix Protein PPXY Late Domain Drives the Production of Defective Interfering Particles.

    Directory of Open Access Journals (Sweden)

    Christopher M Ziegler

    2016-03-01

    Full Text Available Arenaviruses cause severe diseases in humans but establish asymptomatic, lifelong infections in rodent reservoirs. Persistently-infected rodents harbor high levels of defective interfering (DI particles, which are thought to be important for establishing persistence and mitigating virus-induced cytopathic effect. Little is known about what drives the production of DI particles. We show that neither the PPXY late domain encoded within the lymphocytic choriomeningitis virus (LCMV matrix protein nor a functional endosomal sorting complex transport (ESCRT pathway is absolutely required for the generation of standard infectious virus particles. In contrast, DI particle release critically requires the PPXY late domain and is ESCRT-dependent. Additionally, the terminal tyrosine in the PPXY motif is reversibly phosphorylated and our findings indicate that this posttranslational modification may regulate DI particle formation. Thus we have uncovered a new role for the PPXY late domain and a possible mechanism for its regulation.

  2. Breakdown of blood-brain barrier function in the murine lymphocytic choriomeningitis virus infection mediated by virus-specific CD8+ T cells

    DEFF Research Database (Denmark)

    Andersen, I H; Marker, O; Thomsen, Allan Randrup

    1991-01-01

    . It was demonstrated that Thy-1+, CD8+ class I-restricted T cells were mandatory for the increase in BBB permeability as well as for mortality. In addition, depletion of class II-restricted CD4+ cells significantly weakened both effects of cell transfer. These results support the idea of a causal relationship between...... virus-specific T cell activity, BBB dysfunction, and fatal disease. Furthermore, the data indicate that T helper cells augment the response of LCMV-specific CD8+ effector cells....

  3. The role of CD80/CD86 in generation and maintenance of functional virus-specific CD8+ T cells in mice infected with lymphocytic choriomeningitis virus

    DEFF Research Database (Denmark)

    Grujic, Mirjana; Bartholdy, Christina; Remy, Melissa;

    2010-01-01

    , but no chronic infection. Taken together, these results indicate that B7 costimulation is required for induction and maintenance of LCMV-specific CD8(+) T cell memory, irrespective of the LCMV strain used for priming. However, the erosion of CD8(+) T cell memory in B7.1/B7.2(-/-) mice was more pronounced...

  4. Inhibition of Cellular Entry of Lymphocytic Choriomeningitis Virus by Amphipathic DNA Polymers

    Science.gov (United States)

    Lee, Andrew M.; Rojek, Jillian M.; Gundersen, Anette; Ströher, Ute; Juteau, Jean-Marc; Vaillant, Andrew; Kunz, Stefan

    2008-01-01

    The prototypic arenavirus lymphocytic choriomeningitis virus (LCMV) represents a powerful experimental model for the study of the basic virology and pathogenesis of arenaviruses. In the present study, we used the LCMV model to evaluate the anti-viral potential of phosphorothioate oligonucleotides against arenaviruses. Our findings indicate that amphipathic DNA polymers (APs) are potent inhibitors of infection with a series of LCMV isolates with IC50 in the low nanomolar range. APs target the surface glycoprotein (GP) of LCMV and block viral entry and cell-cell propagation of the virus, without affecting later steps in replication or release of progeny virus from infected cells. The anti-viral action of APs is sequence-independent but is critically dependent on their size and hydrophobicity. Mechanistically, we provide evidence that APs disrupt the interaction between LCMVGP and its cellular receptor, α-dystroglycan. Exposure of LCMV to APs does not affect the stability of the GP virion spike and has no effect on the conformation of a neutralizing antibody epitope, suggesting rather subtle changes in the conformation and/or conformational dynamics of the viral GP. PMID:18022208

  5. Differential Impact of Interferon Regulatory Factor 7 in Initiation of the Type I Interferon Response in the Lymphocytic Choriomeningitis Virus-Infected Central Nervous System versus the Periphery

    DEFF Research Database (Denmark)

    Christensen, Jeanette Erbo; Fenger, Christina; Issazadeh-Navikas, Shohreh;

    2012-01-01

    Interferon (IFN) regulatory factors (IRFs) are a family of transcription factors involved in regulating type I IFN genes and other genes participating in the early antiviral host response. To better understand the mechanisms involved in virus-induced central nervous system (CNS) inflammation, we...

  6. Platelets prevent IFN-alpha/beta-induced lethal hemorrhage promoting CTL-dependent clearance of lymphocytic choriomeningitis virus.

    Science.gov (United States)

    Iannacone, Matteo; Sitia, Giovanni; Isogawa, Masanori; Whitmire, Jason K; Marchese, Patrizia; Chisari, Francis V; Ruggeri, Zaverio M; Guidotti, Luca G

    2008-01-15

    We found that mice infected with different isolates of lymphocytic choriomeningitis virus (LCMV) develop a mild hemorrhagic anemia, which becomes severe and eventually lethal in animals depleted of platelets or lacking integrin beta3. Lethal hemorrhagic anemia is mediated by virus-induced IFN-alpha/beta that causes platelet dysfunction, mucocutaneous blood loss and suppression of erythropoiesis. In addition to the life-threatening hemorrhagic anemia, platelet-depleted mice fail to mount an efficient cytotoxic T lymphocyte (CTL) response and cannot clear LCMV. Transfusion of functional platelets into these animals reduces hemorrhage, prevents death and restores CTL-induced viral clearance in a manner partially dependent on CD40 ligand (CD40L). These results indicate that, upon activation, platelets expressing integrin beta3 and CD40L are required for protecting the host against the induction of an IFN-alpha/beta-dependent lethal hemorrhagic diathesis and for clearing LCMV infection through CTLs.

  7. Mechanisms of lymphocytic choriomeningitis virus-induced hemopoietic dysfunction

    DEFF Research Database (Denmark)

    Thomsen, Allan Randrup; Pisa, P; Bro-Jørgensen, K;

    1986-01-01

    function in the intact mouse) mentioned above, we followed the changes in the number of pluripotential stem cells (CFU-S) circulating in the peripheral blood and in endogenous spleen colonies in irradiated mice, the limbs of which were partially shielded. It was found that following a marked early decline......, both parameters increased to normal or supranormal levels at about day 9 after infection. Because the bone marrow pool of CFU-S is only about 20% of normal at this time after infection, a marked tendency for CFU-S at this stage in the infection to migrate from the bone marrow to the spleen is suggested...

  8. Use of single-cycle infectious lymphocytic choriomeningitis virus to study hemorrhagic fever arenaviruses.

    Science.gov (United States)

    Rodrigo, W W Shanaka I; de la Torre, Juan C; Martínez-Sobrido, Luis

    2011-02-01

    Several arenaviruses, chiefly Lassa virus (LASV) and Junin virus in West Africa and Argentina, respectively, cause hemorrhagic fever (HF) disease in humans that is associated with high morbidity and significant mortality. The investigation of antiviral strategies to combat HF arenaviruses is hampered by the requirement of biosafety level 4 (BSL-4) facilities to work with these viruses. These biosafety hurdles could be overcome by the use of recombinant single-cycle infectious arenaviruses. To explore this concept, we have developed a recombinant lymphocytic choriomeningitis virus (LCMV) (rLCMVΔGP/GFP) where we replaced the viral glycoprotein (GP) with the green fluorescent protein (GFP). We generated high titers of GP-pseudotyped rLCMVΔGP/GFP via genetic trans complementation using stable cell lines that constitutively express LCMV or LASV GPs. Replication of these GP-pseudotyped rLCMVΔGP/GFP viruses was restricted to GP-expressing cell lines. This system allowed us to rapidly and reliably characterize and quantify the neutralization activities of serum antibodies against LCMV and LASV within a BSL-2 facility. The sensitivity of the GFP-based microneutralization assay we developed was similar to that obtained with a conventionally used focus reduction neutralization (FRNT) assay. Using GP-pseudotyped rLCMVΔGP/GFP, we have also obtained evidence supporting the feasibility of this approach to identify and evaluate candidate antiviral drugs against HF arenaviruses without the need of BSL-4 laboratories.

  9. Fulminant lymphocytic choriomeningitis virus-induced inflammation of the CNS involves a cytokine-chemokine-cytokine-chemokine cascade

    DEFF Research Database (Denmark)

    Christensen, Jeanette E; Simonsen, Stine; Fenger, Christina;

    2009-01-01

    Intracerebral inoculation of immunocompetent mice with lymphocytic choriomeningitis virus (LCMV) normally results in fatal CD8+ T cell mediated meningoencephalitis. However, in CXCL10-deficient mice, the virus-induced CD8+ T cell accumulation in the neural parenchyma is impaired, and only 30...... of the CNS, and astrocytes are the dominant expressors in the neural parenchyma, not microglial cells or recruited bone marrow-derived cell types. These results are consistent with a model suggesting a bidirectional interplay between resident cells of the CNS and the recruited virus-specific T cells...

  10. CXCL10 is the key ligand for CXCR3 on CD8+ effector T cells involved in immune surveillance of the lymphocytic choriomeningitis virus-infected central nervous system

    DEFF Research Database (Denmark)

    Christensen, Jeanette Erbo; de Lemos, Carina; Moos, Torben;

    2006-01-01

    /ligand pair is thought to play a central role in regulating T cell-mediated inflammation in this organ site. In this report, we investigated the role of CXCL10 in regulating CD8(+) T cell-mediated inflammation in the virus-infected brain. This was done through analysis of CXCL10-deficient mice infected....... Furthermore, despite marked up-regulation of the two remaining CXCR3 ligands: CXCL9 and 11, we found a reduced accumulation of CD8(+) T cells in the brain parenchyma around the time point when wild-type mice succumb as a result of CD8(+) T cell-mediated inflammation. Thus, taken together these results...... indicate a central role for CXCL10 in regulating the accumulation of effector T cells at sites of CNS inflammation, with no apparent compensatory effect of other CXCR3 ligands....

  11. The complementary roles of cellular and humoral immunity in resistance to re-infection with LCM virus

    DEFF Research Database (Denmark)

    Thomsen, Allan Randrup; Marker, O

    1988-01-01

    The mechanisms underlying resistance to re-infection with lymphocytic choriomeningitis virus (LCMV) were investigated. Rechallenge with moderate doses of virus (10(3) LD50) did not lead to detectable re-infection nor to re-induction of virus-specific cytotoxicity. When higher doses of virus were ...

  12. Pet Rodents and Fatal Lymphocytic Choriomeningitis in Transplant Patients

    Centers for Disease Control (CDC) Podcasts

    2007-05-16

    Three organ transplant recipients died from infection with lymphocytic choriomeningitis virus (LCMV), which was traced back to a hamster owned by the daughter of the organ donor. Dr. Brian Amman, a mammalogist with the Special Pathogens Branch at CDC, discusses the dangers LCMV may pose to people with immune disorders, as well as to pregnant women.  Created: 5/16/2007 by CDC, Office of the Director.   Date Released: 5/16/2007.

  13. 9 CFR 113.42 - Detection of lymphocytic choriomeningitis contamination.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Detection of lymphocytic choriomeningitis contamination. 113.42 Section 113.42 Animals and Animal Products ANIMAL AND PLANT HEALTH... contamination. The test for detection of lymphocytic choriomeningitis (LCM) virus provided in this section...

  14. Inducible nitric-oxide synthase plays a minimal role in lymphocytic choriomeningitis virus-induced, T cell-mediated protective immunity and immunopathology

    DEFF Research Database (Denmark)

    Bartholdy, C; Nansen, A; Christensen, Jeanette Erbo;

    1999-01-01

    -mediated immune response was found to be unaltered in iNOS-deficient mice compared with wild-type C57BL/6 mice, and LCMV- induced general immunosuppression was equally pronounced in both strains. In vivo analysis revealed identical kinetics of virus clearance, as well as unaltered clinical severity of systemic......By using mice with a targetted disruption in the gene encoding inducible nitric-oxide synthase (iNOS), we have studied the role of nitric oxide (NO) in lymphocytic choriomeningitis virus (LCMV)-induced, T cell-mediated protective immunity and immunopathology. The afferent phase of the T cell....... This might suggest a role of NO in regulating vascular reactivity in the context of T cell-mediated inflammation. In conclusion, these findings indicate a minimal role for iNOS/NO in the host response to LCMV. Except for a reduced local oedema in the knockout mice, iNOS/NO seems to be redundant...

  15. Wirkung von Cytokinen und cytokininduzierten Proteinen auf die Replikation von Lassa-Virus und Lymphocytärem Choriomeningitis Virus

    OpenAIRE

    Asper, Marcel

    2003-01-01

    Lassa virus is thought to be resistent to the effects of interferon (IFN). This study demonstrates that Lassa virus replication is inhibited by IFN-alpha and IFN-gamma, but not tumor necosis factor alpha (TNF-alpha), in Huh7and Vero cells. However, the effects were orders of magnitudes smaller compared to vesicular stomatitis virus. Lassa virus AV, which had causeda fulminant Lassa fever, was somewhat more inhibited than Lassa virus NL and CSF, which had been associated with less severe disea...

  16. Pathogenesis of Lassa fever virus infection: I. Susceptibility of mice to recombinant Lassa Gp/LCMV chimeric virus.

    Science.gov (United States)

    Lee, Andrew M; Cruite, Justin; Welch, Megan J; Sullivan, Brian; Oldstone, Michael B A

    2013-08-01

    Lassa virus (LASV) is a BSL-4 restricted agent. To allow study of infection by LASV under BSL-2 conditions, we generated a recombinant virus in which the LASV glycoprotein (Gp) was placed on the backbone of lymphocytic choriomeningitis virus (LCMV) Cl13 nucleoprotein, Z and polymerase genes (rLCMV Cl13/LASV Gp). The recombinant virus displayed high tropism for dendritic cells following in vitro or in vivo infection. Inoculation of immunocompetent adults resulted in an acute infection, generation of virus-specific CD8(+) T cells and clearance of the infection. Inoculation of newborn mice with rLCMV Cl13/LASV Gp resulted in a life-long persistent infection. Interestingly, adoptive transfer of rLCMV Cl13/LASV Gp immune memory cells into such persistently infected mice failed to purge virus but, in contrast, cleared virus from mice persistently infected with wt LCMV Cl13.

  17. Virus Infection

    Directory of Open Access Journals (Sweden)

    Hiroshi Abe

    2013-01-01

    Full Text Available Of 168 patients with chronic hepatitis B virus (HBV infection-related liver disease, 20 patients who had received 100 mg of lamivudine plus 10 mg/day of adefovir dipivoxil (ADV (ADV group and 124 patients who had received 0.5 mg/day of entecavir or 100 mg/day of lamivudine (non-ADV group for >1 year were enrolled. For comparative analyses, 19 well-matched pairs were obtained from the groups by propensity scores. At the time of enrollment, serum creatinine and phosphate concentrations were similar between the ADV and non-ADV groups; however, urinary phosphate ( and serum bone-specific alkaline phosphatase (BAP ( concentrations were significantly higher in the ADV group than in the non-ADV group. Serum BAP was significantly higher at the time of enrollment than before ADV administration in the ADV group (, although there was no significant change in serum BAP concentration in the non-ADV group. There was a significant positive correlation between the period of ADV therapy and ΔBAP (, . Serum BAP concentration increased before increase in serum creatinine concentration and was useful for early detection of adverse events and for developing adequate measures for continuing ADV for chronic HBV infection-related liver disease.

  18. Perforin-deficient CD8+ T cells mediate fatal lymphocytic choriomeningitis despite impaired cytokine production

    DEFF Research Database (Denmark)

    Storm, Pernille; Bartholdy, Christina; Sørensen, Maria Rathmann;

    2006-01-01

    Intracerebral (i.c.) infection with lymphocytic choriomeningitis virus (LCMV) is one of the most studied models for virus-induced immunopathology, and based on results from perforin-deficient mice, it is currently assumed that fatal disease directly reflects perforin-mediated cell lysis. However,...... for the delayed onset of fatal disease in perforin-deficient mice. However, once accumulated in the CNS, virus-specific CD8(+) T cells can induce fatal CNS pathology despite the absence of perforin-mediated lysis and reduced capacity to produce several key cytokines....

  19. Viruses infecting reptiles.

    Science.gov (United States)

    Marschang, Rachel E

    2011-11-01

    A large number of viruses have been described in many different reptiles. These viruses include arboviruses that primarily infect mammals or birds as well as viruses that are specific for reptiles. Interest in arboviruses infecting reptiles has mainly focused on the role reptiles may play in the epidemiology of these viruses, especially over winter. Interest in reptile specific viruses has concentrated on both their importance for reptile medicine as well as virus taxonomy and evolution. The impact of many viral infections on reptile health is not known. Koch's postulates have only been fulfilled for a limited number of reptilian viruses. As diagnostic testing becomes more sensitive, multiple infections with various viruses and other infectious agents are also being detected. In most cases the interactions between these different agents are not known. This review provides an update on viruses described in reptiles, the animal species in which they have been detected, and what is known about their taxonomic positions.

  20. Prenatal brain MRI of fetuses with Zika virus infection

    Energy Technology Data Exchange (ETDEWEB)

    Guillemette-Artur, Prisca [Centre Hospitalier de Polynesie Francaise, Service de Radiologie, Pirae, Tahiti (Country Unknown); Besnard, Marianne [Centre Hospitalier de Polynesie Francaise, Service de Reanimation Neo-natale, Pirae, Tahiti (Country Unknown); Eyrolle-Guignot, Dominique [Centre Hospitalier de Polynesie Francaise, Service d' Obstetrique, Pirae, Tahiti (Country Unknown); Jouannic, Jean-Marie [Universite Pierre et Marie Curie, Service de Medecine Foetale, Hopital d' Enfants Armand-Trousseau, Paris (France); Garel, Catherine [Hopital d' Enfants Armand-Trousseau, Department of Radiology, Paris (France)

    2016-06-15

    An outbreak of Zika virus was observed in French Polynesia in 2013-2014. Maternal Zika virus infection has been associated with fetal microcephaly and severe cerebral damage. To analyze the MRI cerebral findings in fetuses with intrauterine Zika virus infection. We retrospectively analyzed prospectively collected data. Inclusion criteria comprised cases with (1) estimated conception date between June 2013 and May 2014, (2) available US and MRI scans revealing severe fetal brain lesions and (3) positive polymerase chain reaction for Zika virus in the amniotic fluid. We recorded pregnancy history of Zika virus infection and analyzed US and MRI scans. Three out of 12 cases of severe cerebral lesions fulfilled all inclusion criteria. History of maternal Zika virus infection had been documented in two cases. Calcifications and ventriculomegaly were present at US in all cases. MRI showed micrencephaly (n = 3), low cerebellar biometry (n = 2), occipital subependymal pseudocysts (n = 2), polymicrogyria with laminar necrosis and opercular dysplasia (n = 3), absent (n = 1) or hypoplastic (n = 1) corpus callosum and hypoplastic brainstem (n = 1). Severe cerebral damage was observed in our series, with indirect findings suggesting that the germinal matrix is the principal target for Zika virus. The lesions are very similar to severe forms of congenital cytomegalovirus and lymphocytic choriomeningitis virus infections. (orig.)

  1. Interleukin-21 mRNA expression during virus infections

    DEFF Research Database (Denmark)

    Holm, Christian; Nyvold, Charlotte Guldborg; Paludan, Søren Riis

    2006-01-01

    and activational effects of IL-21 on different leukocytes come into play in vivo in an immune response has so far not been fully investigated. We show here for the first time in vivo, that IL-21 mRNA is produced in the spleen when mice are challenged with herpes simplex virus type 2 (HSV-2) or lymphocytic...... choriomeningitis virus (LCMV). We show in HSV-2 challenged mice that this production takes place in CD4+ T cell fractions and is absent in CD4+ T cell-depleted fractions. We also show that the peak of IL-21 mRNA production in both the HSV-2 and LCMV-challenged mice coincides with the onset of the adaptive immune...... response. Thus, our data suggest a role for IL-21 in the early stages of adaptive immune response against virus infections....

  2. Fulminant lymphocytic choriomeningitis virus-induced inflammation of the CNS involves a cytokine-chemokine-cytokine-chemokine cascade

    DEFF Research Database (Denmark)

    Christensen, Jeanette Erbo; Simonsen, Stine; Fenger, Christina;

    2009-01-01

    the expression of CXCL10 in the CNS of LCMV-infected mice. Using mice deficient in type I IFN receptor, type II IFN receptor, or type II IFN, as well as bone marrow chimeras expressing CXCL10 only in resident cells or only in bone marrow-derived cells, we analyzed the up-stream regulation as well as the cellular...

  3. Alpha 4 integrin directs virus-activated CD8+ T cells to sites of infection

    DEFF Research Database (Denmark)

    Christensen, Jan Pravsgaard; Andersson, E C; Scheynius, A;

    1995-01-01

    This article examines the role of VLA-4 in directing lymphocytes to sites of viral infection using the murine lymphocytic choriomeningitis virus infection (LCMV) as the model system. This virus by itself induces little or no inflammation, but in most mouse/virus strain combinations a potent T cell...... infection results in the appearance of activated CD8+ cells with an increased expression of VLA-4. In this study we have compared various T cell high and low responder situations, and these experiments revealed that acute inflammation correlates directly with VLA-4 expression on splenic CD8+ cells....... This correlation could be extended to CD4+ and B cells in chronically infected low responder DBA/2 mice. The vascular ligand for VLA-4, VCAM-1, was found to be up-regulated on endothelial cells in sites of inflammation. Finally, preincubation of virus-primed donor cells with mAb to VLA-4 completely blocked...

  4. Zika virus infection.

    Science.gov (United States)

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

    2016-12-01

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

  5. [ZIKA--VIRUS INFECTION].

    Science.gov (United States)

    Velev, V

    2016-01-01

    This review summarizes the knowledge of the scientific community for Zika-virus infection. It became popular because of severe congenital damage causes of CNS in newborns whose mothers are infected during pregnancy, as well as the risk of pandemic distribution. Discusses the peculiarities of the biology and ecology of vectors--blood-sucking mosquitoes Aedes; stages in the spread of infection and practical problems which caused during pregnancy. Attention is paid to the recommendations that allow leading national and international medical organizations to deal with the threat Zika-virus infection.

  6. Comportamiento de cepas argentinas del virus de la Coriomeningitis Linfocitaria en roedores Behavior of Argentine lymphocytic choriomeningitis virus strains in rodents

    Directory of Open Access Journals (Sweden)

    María Del Cármen Saavedra

    2007-10-01

    strains WE and Armstrong. Regarding the results obtained in tissue culture, when L 929 cells were used, plaque forming units (PFU were obtained with human and mouse strains, whilst on Vero cells only human strains developed PFU. Differentials characteristics of historical and Argentine strain's plates were not found, neither differences related to the strain's origin. Neither historical nor Argentine strains were lethal to new-born mice giving a persistent infection, that was demonstrated when we inoculated new-born mouse by intracranial route with different strains of LCM virus and virus was isolated from brains harvested at different days post inoculation. The only exception was Cba An 13065 strain that exhibited virulence in new-born mice, only with 0.026 PFU was obtained 1 DL50. All the strains resulted lethal to adult mice. The mouse strains were more virulent than human strains, being Cba An 13065 the most virulent. These results demonstrate a different behavior in tissue culture between human and mouse strains and allow the identification of virulence markers by intracranial inoculation into new-born or adult mice.

  7. Human Influenza Virus Infections.

    Science.gov (United States)

    Peteranderl, Christin; Herold, Susanne; Schmoldt, Carole

    2016-08-01

    Seasonal and pandemic influenza are the two faces of respiratory infections caused by influenza viruses in humans. As seasonal influenza occurs on an annual basis, the circulating virus strains are closely monitored and a yearly updated vaccination is provided, especially to identified risk populations. Nonetheless, influenza virus infection may result in pneumonia and acute respiratory failure, frequently complicated by bacterial coinfection. Pandemics are, in contrary, unexpected rare events related to the emergence of a reassorted human-pathogenic influenza A virus (IAV) strains that often causes increased morbidity and spreads extremely rapidly in the immunologically naive human population, with huge clinical and economic impact. Accordingly, particular efforts are made to advance our knowledge on the disease biology and pathology and recent studies have brought new insights into IAV adaptation mechanisms to the human host, as well as into the key players in disease pathogenesis on the host side. Current antiviral strategies are only efficient at the early stages of the disease and are challenged by the genomic instability of the virus, highlighting the need for novel antiviral therapies targeting the pulmonary host response to improve viral clearance, reduce the risk of bacterial coinfection, and prevent or attenuate acute lung injury. This review article summarizes our current knowledge on the molecular basis of influenza infection and disease progression, the key players in pathogenesis driving severe disease and progression to lung failure, as well as available and envisioned prevention and treatment strategies against influenza virus infection.

  8. [West Nile virus infection].

    Science.gov (United States)

    Pérez Ruiz, Mercedes; Gámez, Sara Sanbonmatsu; Clavero, Miguel Angel Jiménez

    2011-12-01

    West Nile virus (WNV) is an arbovirus usually transmitted by mosquitoes. The main reservoirs are birds, although the virus may infect several vertebrate species, such as horses and humans. Up to 80% of human infections are asymptomatic. The most frequent clinical presentation is febrile illness, and neuroinvasive disease can occur in less than 1% of cases. Spain is considered a high-risk area for the emergence of WNV due to its climate and the passage of migratory birds from Africa (where the virus is endemic). These birds nest surrounding wetlands where populations of possible vectors for the virus are abundant. Diagnosis of human neurological infections can be made by detection of IgM in serum and/or cerebrospinal fluid samples, demonstration of a four-fold increase in IgG antibodies between acute-phase and convalescent-phase serum samples, or by detection of viral genome by reverse transcription-polymerase chain reaction (especially useful in transplant recipients). Since WNV is a biosafety level 3 agent, techniques that involve cell culture are restricted to laboratories with this level of biosafety, such as reference laboratories. The National Program for the Surveillance of WNV Encephalitis allows the detection of virus circulation among birds and vectors in areas especially favorable for the virus, such as wetlands, and provides information for evaluation of the risk of disease in horses and humans.

  9. Zika Virus Infection and Microcephaly.

    Science.gov (United States)

    Millichap, J Gordon

    2016-01-01

    A Task Force established by the Brazil Ministry of Health investigated the possible association of microcephaly with Zika virus infection during pregnancy and a registry for microcephaly cases among women suspected to have had Zika virus infection during pregnancy.

  10. Zika Virus Infection and Microcephaly

    OpenAIRE

    J Gordon Millichap

    2016-01-01

    A Task Force established by the Brazil Ministry of Health investigated the possible association of microcephaly with Zika virus infection during pregnancy and a registry for microcephaly cases among women suspected to have had Zika virus infection during pregnancy.

  11. [Zika virus infection during pregnancy].

    Science.gov (United States)

    Picone, O; Vauloup-Fellous, C; D'Ortenzio, E; Huissoud, C; Carles, G; Benachi, A; Faye, A; Luton, D; Paty, M-C; Ayoubi, J-M; Yazdanpanah, Y; Mandelbrot, L; Matheron, S

    2016-05-01

    A Zika virus epidemic is currently ongoing in the Americas. This virus is linked to congenital infections with potential severe neurodevelopmental dysfunction. However, incidence of fetal infection and whether this virus is responsible of other fetal complications are still unknown. National and international public health authorities recommend caution and several prevention measures. Declaration of Zika virus infection is now mandatory in France. Given the available knowledge on Zika virus, we suggest here a review of the current recommendations for management of pregnancy in case of suspicious or infection by Zika virus in a pregnant woman.

  12. Suppressors of cytokine signaling 1 and 3 are up-regulated in brain resident cells in response to virus induced inflammation of the CNS via at least two distinctive pathways

    DEFF Research Database (Denmark)

    Steffensen, Maria Abildgaard; Fenger, Christina; Christensen, Jeanette Erbo

    2014-01-01

    underlie a virus induced up-regulation of SOCS in the CNS. We found that i.c. infection with either lymphocytic choriomeningitis virus (LCMV) or yellow fever virus (YF) results in gradual up-regulation of SOCS1/3 mRNA expression peaking at day 7 post infection (p.i.). In the LCMV model, SOCS m...

  13. Zika Virus Infection and Microcephaly

    Directory of Open Access Journals (Sweden)

    J. Gordon Millichap

    2016-03-01

    Full Text Available A Task Force established by the Brazil Ministry of Health investigated the possible association of microcephaly with Zika virus infection during pregnancy and a registry for microcephaly cases among women suspected to have had Zika virus infection during pregnancy.

  14. Conserved residues in Lassa fever virus Z protein modulate viral infectivity at the level of the ribonucleoprotein.

    Science.gov (United States)

    Capul, Althea A; de la Torre, Juan Carlos; Buchmeier, Michael J

    2011-04-01

    Arenaviruses are negative-strand RNA viruses that cause human diseases such as lymphocytic choriomeningitis, Bolivian hemorrhagic fever, and Lassa hemorrhagic fever. No licensed vaccines exist, and current treatment is limited to ribavirin. The prototypic arenavirus, lymphocytic choriomeningitis virus (LCMV), is a model for dissecting virus-host interactions in persistent and acute disease. The RING finger protein Z has been identified as the driving force of arenaviral budding and acts as the viral matrix protein. While residues in Z required for viral budding have been described, residues that govern the Z matrix function(s) have yet to be fully elucidated. Because this matrix function is integral to viral assembly, we reasoned that this would be reflected in sequence conservation. Using sequence alignment, we identified several conserved residues in Z outside the RING and late domains. Nine residues were each mutated to alanine in Lassa fever virus Z. All of the mutations affected the expression of an LCMV minigenome and the infectivity of virus-like particles, but to greatly varying degrees. Interestingly, no mutations appeared to affect Z-mediated budding or association with viral GP. Our findings provide direct experimental evidence supporting a role for Z in the modulation of the activity of the viral ribonucleoprotein (RNP) complex and its packaging into mature infectious viral particles.

  15. Avian Influenza A Virus Infections in Humans

    Science.gov (United States)

    ... their saliva, mucous and feces. Human infections with bird flu viruses can happen when enough virus gets into ... Virus (CVV) for a Highly Pathogenic Avian Influenza (Bird Flu) Virus ” for more information on this process. ...

  16. Dengue virus antibodies enhance Zika virus infection

    Science.gov (United States)

    Paul, Lauren M; Carlin, Eric R; Jenkins, Meagan M; Tan, Amanda L; Barcellona, Carolyn M; Nicholson, Cindo O; Michael, Scott F; Isern, Sharon

    2016-01-01

    For decades, human infections with Zika virus (ZIKV), a mosquito-transmitted flavivirus, were sporadic, associated with mild disease, and went underreported since symptoms were similar to other acute febrile diseases. Recent reports of severe disease associated with ZIKV have greatly heightened awareness. It is anticipated that ZIKV will continue to spread in the Americas and globally where competent Aedes mosquito vectors are found. Dengue virus (DENV), the most common mosquito-transmitted human flavivirus, is both well-established and the source of outbreaks in areas of recent ZIKV introduction. DENV and ZIKV are closely related, resulting in substantial antigenic overlap. Through antibody-dependent enhancement (ADE), anti-DENV antibodies can enhance the infectivity of DENV for certain classes of immune cells, causing increased viral production that correlates with severe disease outcomes. Similarly, ZIKV has been shown to undergo ADE in response to antibodies generated by other flaviviruses. We tested the neutralizing and enhancing potential of well-characterized broadly neutralizing human anti-DENV monoclonal antibodies (HMAbs) and human DENV immune sera against ZIKV using neutralization and ADE assays. We show that anti-DENV HMAbs, cross-react, do not neutralize, and greatly enhance ZIKV infection in vitro. DENV immune sera had varying degrees of neutralization against ZIKV and similarly enhanced ZIKV infection. Our results suggest that pre-existing DENV immunity may enhance ZIKV infection in vivo and may lead to increased disease severity. Understanding the interplay between ZIKV and DENV will be critical in informing public health responses and will be particularly valuable for ZIKV and DENV vaccine design and implementation strategies. PMID:28090318

  17. Hepatitis Virus Infections in Poultry.

    Science.gov (United States)

    Yugo, Danielle M; Hauck, Ruediger; Shivaprasad, H L; Meng, Xiang-Jin

    2016-09-01

    Viral hepatitis in poultry is a complex disease syndrome caused by several viruses belonging to different families including avian hepatitis E virus (HEV), duck hepatitis B virus (DHBV), duck hepatitis A virus (DHAV-1, -2, -3), duck hepatitis virus Types 2 and 3, fowl adenoviruses (FAdV), and turkey hepatitis virus (THV). While these hepatitis viruses share the same target organ, the liver, they each possess unique clinical and biological features. In this article, we aim to review the common and unique features of major poultry hepatitis viruses in an effort to identify the knowledge gaps and aid the prevention and control of poultry viral hepatitis. Avian HEV is an Orthohepevirus B in the family Hepeviridae that naturally infects chickens and consists of three distinct genotypes worldwide. Avian HEV is associated with hepatitis-splenomegaly syndrome or big liver and spleen disease in chickens, although the majority of the infected birds are subclinical. Avihepadnaviruses in the family of Hepadnaviridae have been isolated from ducks, snow geese, white storks, grey herons, cranes, and parrots. DHBV evolved with the host as a noncytopathic form without clinical signs and rarely progressed to chronicity. The outcome for DHBV infection varies by the host's ability to elicit an immune response and is dose and age dependent in ducks, thus mimicking the pathogenesis of human hepatitis B virus (HBV) infections and providing an excellent animal model for human HBV. DHAV is a picornavirus that causes a highly contagious virus infection in ducks with up to 100% flock mortality in ducklings under 6 wk of age, while older birds remain unaffected. The high morbidity and mortality has an economic impact on intensive duck production farming. Duck hepatitis virus Types 2 and 3 are astroviruses in the family of Astroviridae with similarity phylogenetically to turkey astroviruses, implicating the potential for cross-species infections between strains. Duck astrovirus (DAstV) causes

  18. Probiotics in respiratory virus infections.

    Science.gov (United States)

    Lehtoranta, L; Pitkäranta, A; Korpela, R

    2014-08-01

    Viral respiratory infections are the most common diseases in humans. A large range of etiologic agents challenge the development of efficient therapies. Research suggests that probiotics are able to decrease the risk or duration of respiratory infection symptoms. However, the antiviral mechanisms of probiotics are unclear. The purpose of this paper is to review the current knowledge on the effects of probiotics on respiratory virus infections and to provide insights on the possible antiviral mechanisms of probiotics. A PubMed and Scopus database search was performed up to January 2014 using appropriate search terms on probiotic and respiratory virus infections in cell models, in animal models, and in humans, and reviewed for their relevance. Altogether, thirty-three clinical trials were reviewed. The studies varied highly in study design, outcome measures, probiotics, dose, and matrices used. Twenty-eight trials reported that probiotics had beneficial effects in the outcome of respiratory tract infections (RTIs) and five showed no clear benefit. Only eight studies reported investigating viral etiology from the respiratory tract, and one of these reported a significant decrease in viral load. Based on experimental studies, probiotics may exert antiviral effects directly in probiotic-virus interaction or via stimulation of the immune system. Although probiotics seem to be beneficial in respiratory illnesses, the role of probiotics on specific viruses has not been investigated sufficiently. Due to the lack of confirmatory studies and varied data available, more randomized, double-blind, and placebo-controlled trials in different age populations investigating probiotic dose response, comparing probiotic strains/genera, and elucidating the antiviral effect mechanisms are necessary.

  19. Non-MHC genes influence virus clearance through regulation of the antiviral T-cell response: correlation between virus clearance and Tc and Td activity in segregating backcross progeny

    DEFF Research Database (Denmark)

    Christensen, Jan Pravsgaard; Marker, O; Thomsen, Allan Randrup

    1994-01-01

    To determine the mechanism by which non-MHC genes control the rate of virus clearance in mice infected with lymphocytic choriomeningitis virus, a segregating backcross population was studied. Thirty BC1 animals were infected with virus, and virus-specific delayed-type hypersensitivity (DTH...... and the ability to clear virus. Amongst Tc low responders a correlation between DTH reactivity and virus clearance was observed. Taken together, these results indicate that non-MHC genes affect virus clearance through regulation of the antiviral T-cell response, especially the virus-specific Tc response. However...

  20. BK virus infection in human immunodeficiency virus-infected patients.

    Science.gov (United States)

    Ledesma, J; Muñoz, P; Garcia de Viedma, D; Cabrero, I; Loeches, B; Montilla, P; Gijon, P; Rodriguez-Sanchez, B; Bouza, E

    2012-07-01

    The aim of this study is to evaluate the prevalence of BK virus (BKV) infection in HIV-positive patients receiving highly active antiretroviral therapy (HAART) in our hospital. The presence of BKV was analysed in urine and plasma samples from 78 non-selected HIV-infected patients. Clinical data were recorded using a pre-established protocol. We used a nested PCR to amplify a specific region of the BKV T-large antigen. Positive samples were quantified using real-time PCR. Mean CD4 count in HIV-infected patients was 472 cells/mm3 and median HIV viral load was 500 cells/mm3 (74.3% vs 25.7%; p=0.007). Viruria was present in 21.7% of healthy controls (5 out of 23 samples, p=0.02). All viral loads were low (<100 copies/mL), and we could not find any association between BKV infection and renal or neurological manifestations. We provide an update on the prevalence of BKV in HIV-infected patients treated with HAART. BKV viruria was more common in HIV-infected patients; however, no role for BKV has been demonstrated in this population.

  1. Hepatic disorder in Zika virus infection

    Institute of Scientific and Technical Information of China (English)

    Viroj Wiwanitkit

    2016-01-01

    Zika virus infection is the present global problem. This arbovirus infection can cause acute ilness and affect fetus in utero. However, there can be other additional clinical manifestation including to the hepatic disorder. In this short commentary article, the author brielfy discusses on the liver problem due to Zika virus infection.

  2. CNS recruitment of CD8+ T lymphocytes specific for a peripheral virus infection triggers neuropathogenesis during polymicrobial challenge.

    Directory of Open Access Journals (Sweden)

    Christine M Matullo

    2011-12-01

    Full Text Available Although viruses have been implicated in central nervous system (CNS diseases of unknown etiology, including multiple sclerosis and amyotrophic lateral sclerosis, the reproducible identification of viral triggers in such diseases has been largely unsuccessful. Here, we explore the hypothesis that viruses need not replicate in the tissue in which they cause disease; specifically, that a peripheral infection might trigger CNS pathology. To test this idea, we utilized a transgenic mouse model in which we found that immune cells responding to a peripheral infection are recruited to the CNS, where they trigger neurological damage. In this model, mice are infected with both CNS-restricted measles virus (MV and peripherally restricted lymphocytic choriomeningitis virus (LCMV. While infection with either virus alone resulted in no illness, infection with both viruses caused disease in all mice, with ∼50% dying following seizures. Co-infection resulted in a 12-fold increase in the number of CD8+ T cells in the brain as compared to MV infection alone. Tetramer analysis revealed that a substantial proportion (>35% of these infiltrating CD8+ lymphocytes were LCMV-specific, despite no detectable LCMV in CNS tissues. Mechanistically, CNS disease was due to edema, induced in a CD8-dependent but perforin-independent manner, and brain herniation, similar to that observed in mice challenged intracerebrally with LCMV. These results indicate that T cell trafficking can be influenced by other ongoing immune challenges, and that CD8+ T cell recruitment to the brain can trigger CNS disease in the apparent absence of cognate antigen. By extrapolation, human CNS diseases of unknown etiology need not be associated with infection with any particular agent; rather, a condition that compromises and activates the blood-brain barrier and adjacent brain parenchyma can render the CNS susceptible to pathogen-independent immune attack.

  3. Acute otitis media and respiratory virus infections.

    Science.gov (United States)

    Ruuskanen, O; Arola, M; Putto-Laurila, A; Mertsola, J; Meurman, O; Viljanen, M K; Halonen, P

    1989-02-01

    We studied the association of acute otitis media with different respiratory virus infections in a pediatric department on the basis of epidemics between 1980 and 1985. Altogether 4524 cases of acute otitis media were diagnosed. The diagnosis was confirmed by tympanocentesis in 3332 ears. Respiratory virus infection was diagnosed during the same period in 989 patients by detecting viral antigen in nasopharyngeal mucus. There was a significant correlation between acute otitis media and respiratory virus epidemics, especially respiratory syncytial virus epidemics. There was no significant correlation between outbreaks of other respiratory viruses and acute otitis media. Acute otitis media was diagnosed in 57% of respiratory syncytial virus, 35% of influenza A virus, 33% of parainfluenza type 3 virus, 30% of adenovirus, 28% of parainfluenza type 1 virus, 18% of influenza B virus and 10% of parainfluenza type 2 virus infections. These observations show a clear association of respiratory virus infections with acute otitis media. In this study on hospitalized children Haemophilus influenzae strains were the most common bacteriologic pathogens in middle ear fluid, occurring in 19% of cases. Streptococcus pneumoniae was present in 16% and Branhamella catarrhalis in 7% of cases. There was no association between specific viruses and bacteria observed in this study.

  4. [Occult hepatitis C virus infection].

    Science.gov (United States)

    Carreño García, Vicente; Nebreda, Javier Bartolomé; Aguilar, Inmaculada Castillo; Quiroga Estévez, Juan Antonio

    2011-03-01

    Occult hepatitis C virus (HCV) infection is characterized by the detection of HCV-RNA in liver in the absence of anti-HCV and serum HCV-RNA determined by conventional techniques. The development of a new enzyme immunoassay for the detection of antibodies against a conserved epitope in the HCV core protein, together with the detection of HCV-RNA in peripheral blood mononuclear cells and in serum after concentrating the viral particles by ultracentrifugation, allow diagnosis of more than 90% of patients with occult HCV without the need to perform a liver biopsy. Histological damage in occult HCV infection ranges from minimal changes to liver cirrhosis and hepatocellular carcinoma, although in general this disease is less severe than classical chronic hepatitis C. A significant prevalence of occult HCV infection has been identified in risk groups such as hemodialysis patients and the family members of patients with occult hepatitis C. This occult HCV infection can also be found in subjects without clinical or biochemical evidence of liver disease.

  5. Polyphasic innate immune responses to acute and chronic LCMV infection: Innate immunity to acute & chronic viral infection

    OpenAIRE

    Norris, Brian A; Uebelhoer, Luke S.; Nakaya, Helder I.; Price, Aryn A; Grakoui, Arash; Pulendran, Bali

    2013-01-01

    Resolution of acute and chronic viral infections requires activation of innate cells to initiate and maintain adaptive immune responses. Here we report that infection with acute Armstrong (ARM) or chronic Clone 13 (C13) strains of lymphocytic choriomeningitis virus (LCMV) led to two distinct phases of innate immune response. During the first 72hr of infection, dendritic cells upregulated activation markers, and stimulated anti-viral CD8+ T cells, independent of viral strain. Seven days after ...

  6. Medicinal herbs for hepatitis C virus infection

    DEFF Research Database (Denmark)

    Liu, Jianping; Manheimer, Eric; Tsutani, Kiichiro

    2003-01-01

    The aim of this study was to assess beneficial and harmful effects of medicinal herbs for hepatitis C virus (HCV) infection.......The aim of this study was to assess beneficial and harmful effects of medicinal herbs for hepatitis C virus (HCV) infection....

  7. Chikungunya virus infection in travellers to Australia.

    Science.gov (United States)

    Johnson, Douglas F; Druce, Julian D; Chapman, Scott; Swaminathan, Ashwin; Wolf, Josh; Richards, Jack S; Korman, Tony; Birch, Chris; Richards, Michael J

    2008-01-07

    We report eight recent cases of Chikungunya virus infection in travellers to Australia. Patients presented with fevers, rigors, headaches, arthralgia, and rash. The current Indian Ocean epidemic and Italian outbreak have featured prominently on Internet infectious disease bulletins, and Chikungunya virus infection had been anticipated in travellers from the outbreak areas. Diagnosis was by a generic alphavirus reverse transcriptase polymerase chain reaction with confirmatory sequencing. Prompt diagnosis of Chikungunya virus infections is of public health significance as the mosquito vectors for transmission exist in Australia. There is potential for this infection to spread in the largely naïve Australian population.

  8. Interleukin-21 mRNA expression during virus infections

    DEFF Research Database (Denmark)

    Holm, Christian; Nyvold, C.G.; Paludan, Søren Riis;

    2006-01-01

    and activational effects of IL-21 on different leukocytes come into play in vivo in an immune response has so far not been fully investigated. We show here for the first time in vivo, that IL-21 mRNA is produced in the spleen when mice are challenged with herpes simplex virus type 2 (HSV-2) or lymphocytic...... choriomeningitis virus (LCMV). We show in HSV-2 challenged mice that this production takes place in CD4+ T cell fractions and is absent in CD4+ T cell-depleted fractions. We also show that the peak of IL-21 mRNA production in both the HSV-2 and LCMV-challenged mice coincides with the onset of the adaptive immune...

  9. Hepatitis A virus infection presenting with seizures.

    Science.gov (United States)

    Cam, Sebahat; Ertem, Deniz; Koroglu, Ozge Altun; Pehlivanoglu, Ender

    2005-07-01

    Hepatitis A infection rarely causes extrahepatic manifestations. Here we present a 5-year-old patient with an initial complaint of nuchal rigidity and convulsions during the course of hepatitis A infection. Because hepatitis A virus RNA was demonstrated in the cerebrospinal fluid, it was thought that convulsions might be related to this viral infection.

  10. Zika Virus Infection: Current Concerns and Perspectives.

    Science.gov (United States)

    Maharajan, Mari Kannan; Ranjan, Aruna; Chu, Jian Feng; Foo, Wei Lim; Chai, Zhi Xin; Lau, Eileen YinYien; Ye, Heuy Mien; Theam, Xi Jin; Lok, Yen Ling

    2016-12-01

    The Zika virus outbreaks highlight the growing importance need for a reliable, specific and rapid diagnostic device to detect Zika virus, as it is often recognized as a mild disease without being identified. Many Zika virus infection cases have been misdiagnosed or underreported because of the non-specific clinical presentation. The aim of this review was to provide a critical and comprehensive overview of the published peer-reviewed evidence related to clinical presentations, various diagnostic methods and modes of transmission of Zika virus infection, as well as potential therapeutic targets to combat microcephaly. Zika virus is mainly transmitted through bites from Aedes aegypti mosquito. It can also be transmitted through blood, perinatally and sexually. Pregnant women are advised to postpone or avoid travelling to areas where active Zika virus transmission is reported, as this infection is directly linked to foetal microcephaly. Due to the high prevalence of Guillain-Barre syndrome and microcephaly in the endemic area, it is vital to confirm the diagnosis of Zika virus. Zika virus infection had been declared as a public health emergency and of international concern by the World Health Organisation. Governments and agencies should play an important role in terms of investing time and resources to fundamentally understand this infection so that a vaccine can be developed besides raising awareness.

  11. Interferon-γ Inhibits Ebola Virus Infection.

    Science.gov (United States)

    Rhein, Bethany A; Powers, Linda S; Rogers, Kai; Anantpadma, Manu; Singh, Brajesh K; Sakurai, Yasuteru; Bair, Thomas; Miller-Hunt, Catherine; Sinn, Patrick; Davey, Robert A; Monick, Martha M; Maury, Wendy

    2015-01-01

    Ebola virus outbreaks, such as the 2014 Makona epidemic in West Africa, are episodic and deadly. Filovirus antivirals are currently not clinically available. Our findings suggest interferon gamma, an FDA-approved drug, may serve as a novel and effective prophylactic or treatment option. Using mouse-adapted Ebola virus, we found that murine interferon gamma administered 24 hours before or after infection robustly protects lethally-challenged mice and reduces morbidity and serum viral titers. Furthermore, we demonstrated that interferon gamma profoundly inhibits Ebola virus infection of macrophages, an early cellular target of infection. As early as six hours following in vitro infection, Ebola virus RNA levels in interferon gamma-treated macrophages were lower than in infected, untreated cells. Addition of the protein synthesis inhibitor, cycloheximide, to interferon gamma-treated macrophages did not further reduce viral RNA levels, suggesting that interferon gamma blocks life cycle events that require protein synthesis such as virus replication. Microarray studies with interferon gamma-treated human macrophages identified more than 160 interferon-stimulated genes. Ectopic expression of a select group of these genes inhibited Ebola virus infection. These studies provide new potential avenues for antiviral targeting as these genes that have not previously appreciated to inhibit negative strand RNA viruses and specifically Ebola virus infection. As treatment of interferon gamma robustly protects mice from lethal Ebola virus infection, we propose that interferon gamma should be further evaluated for its efficacy as a prophylactic and/or therapeutic strategy against filoviruses. Use of this FDA-approved drug could rapidly be deployed during future outbreaks.

  12. Interferon-γ Inhibits Ebola Virus Infection.

    Directory of Open Access Journals (Sweden)

    Bethany A Rhein

    Full Text Available Ebola virus outbreaks, such as the 2014 Makona epidemic in West Africa, are episodic and deadly. Filovirus antivirals are currently not clinically available. Our findings suggest interferon gamma, an FDA-approved drug, may serve as a novel and effective prophylactic or treatment option. Using mouse-adapted Ebola virus, we found that murine interferon gamma administered 24 hours before or after infection robustly protects lethally-challenged mice and reduces morbidity and serum viral titers. Furthermore, we demonstrated that interferon gamma profoundly inhibits Ebola virus infection of macrophages, an early cellular target of infection. As early as six hours following in vitro infection, Ebola virus RNA levels in interferon gamma-treated macrophages were lower than in infected, untreated cells. Addition of the protein synthesis inhibitor, cycloheximide, to interferon gamma-treated macrophages did not further reduce viral RNA levels, suggesting that interferon gamma blocks life cycle events that require protein synthesis such as virus replication. Microarray studies with interferon gamma-treated human macrophages identified more than 160 interferon-stimulated genes. Ectopic expression of a select group of these genes inhibited Ebola virus infection. These studies provide new potential avenues for antiviral targeting as these genes that have not previously appreciated to inhibit negative strand RNA viruses and specifically Ebola virus infection. As treatment of interferon gamma robustly protects mice from lethal Ebola virus infection, we propose that interferon gamma should be further evaluated for its efficacy as a prophylactic and/or therapeutic strategy against filoviruses. Use of this FDA-approved drug could rapidly be deployed during future outbreaks.

  13. Saffold virus infection associated with human myocarditis

    DEFF Research Database (Denmark)

    Nielsen, Trine Skov; Nielsen, Alex Yde; Banner, Jytte

    2016-01-01

    BACKGROUND: Saffold virus was described in 2007 as one of the first human viruses within the genus cardioviruses. Cardioviruses may cause severe infections of the myocardium in animals, and several studies have associated saffold virus with human disease. As a result, saffold virus has been...... isolated from different anatomical compartments, including the myocardium, but, until now, it has not been possible to demonstrate the accompanying histopathological signs of inflammation. OBJECTIVES: The aim of the study was to examine if saffold virus is capable of causing invasive infection in the human...... myocardium. STUDY DESIGN: Using real-time PCR, we retrospectively examined formalin-fixed paraffin embedded cardiac tissue specimens from 150 deceased individuals diagnosed with myocarditis at autopsy. The results were compared with histological findings. RESULTS AND CONCLUSIONS: Saffold virus was detected...

  14. Dengue Virus Infection Perturbs Lipid Homeostasis in Infected Mosquito Cells

    Energy Technology Data Exchange (ETDEWEB)

    Perera, Rushika M.; Riley, Catherine; Isaac, Georgis; Hopf- Jannasch, Amber; Moore, Ronald J.; Weitz, Karl K.; Pasa-Tolic, Ljiljana; Metz, Thomas O.; Adamec, Jiri; Kuhn, Richard J.

    2012-03-22

    Dengue virus causes {approx}50-100 million infections per year and thus is considered one of the most aggressive arthropod-borne human pathogen worldwide. During its replication, dengue virus induces dramatic alterations in the intracellular membranes of infected cells. This phenomenon is observed both in human and vector-derived cells. Using high-resolution mass spectrometry of mosquito cells, we show that this membrane remodeling is directly linked to a unique lipid repertoire induced by dengue virus infection. Specifically, 15% of the metabolites detected were significantly different between DENV infected and uninfected cells while 85% of the metabolites detected were significantly different in isolated replication complex membranes. Furthermore, we demonstrate that intracellular lipid redistribution induced by the inhibition of fatty acid synthase, the rate-limiting enzyme in lipid biosynthesis, is sufficient for cell survival but is inhibitory to dengue virus replication. Lipids that have the capacity to destabilize and change the curvature of membranes as well as lipids that change the permeability of membranes are enriched in dengue virus infected cells. Several sphingolipids and other bioactive signaling molecules that are involved in controlling membrane fusion, fission, and trafficking as well as molecules that influence cytoskeletal reorganization are also up regulated during dengue infection. These observations shed light on the emerging role of lipids in shaping the membrane and protein environments during viral infections and suggest membrane-organizing principles that may influence virus-induced intracellular membrane architecture.

  15. Imported Mayaro virus infection in the Netherlands.

    Science.gov (United States)

    Hassing, Robert-Jan; Leparc-Goffart, Isabelle; Blank, Sybrandus N; Thevarayan, Subashini; Tolou, Hugues; van Doornum, Gerard; van Genderen, Perry J

    2010-10-01

    A Dutch couple, presenting with persisting arthralgias, temporary fever and rash after a stay in Surinam were diagnosed with Mayaro virus infection. Mayaro virus is a relatively unknown South American Alphavirus responsible for dengue-like clinical features and persisting arthralgias. An important, but probably underappreciated cross-reactivity with other Alphaviruses like Chikungunya virus is present, which may become of clinical importance in the event the various Alphaviruses will have overlapping geographical distributions and in seroprevalence studies.

  16. Herpes simplex virus infection during pregnancy.

    Science.gov (United States)

    Stephenson-Famy, Alyssa; Gardella, Carolyn

    2014-12-01

    Genital herpes in pregnancy continues to cause significant maternal morbidity, with an increasing number of infections being due to oral-labial transmission of herpes simplex virus (HSV)-1. Near delivery, primary infections with HSV-1 or HSV-2 carry the highest risk of neonatal herpes infection, which is a rare but potentially devastating disease for otherwise healthy newborns. Prevention efforts have been limited by lack of an effective intervention for preventing primary infections and the unclear role of routine serologic testing.

  17. Life-Threatening Sochi Virus Infections, Russia.

    Science.gov (United States)

    Kruger, Detlev H; Tkachenko, Evgeniy A; Morozov, Vyacheslav G; Yunicheva, Yulia V; Pilikova, Olga M; Malkin, Gennadiy; Ishmukhametov, Aydar A; Heinemann, Patrick; Witkowski, Peter T; Klempa, Boris; Dzagurova, Tamara K

    2015-12-01

    Sochi virus was recently identified as a new hantavirus genotype carried by the Black Sea field mouse, Apodemus ponticus. We evaluated 62 patients in Russia with Sochi virus infection. Most clinical cases were severe, and the case-fatality rate was as high as 14.5%.

  18. Virus infections of honeybees Apis Mellifera

    Directory of Open Access Journals (Sweden)

    Giuseppina Tantillo

    2015-09-01

    Full Text Available The health and vigour of honeybee colonies are threatened by numerous parasites (such as Varroa destructor and Nosema spp. and pathogens, including viruses, bacteria, protozoa. Among honeybee pathogens, viruses are one of the major threats to the health and wellbeing of honeybees and cause serious concern for researchers and beekeepers. To tone down the threats posed by these invasive organisms, a better understanding of bee viral infections will be of crucial importance in developing effective and environmentally benign disease control strategies. Here we summarize recent progress in the understanding of the morphology, genome organization, transmission, epidemiology and pathogenesis of eight honeybee viruses: Deformed wing virus (DWV and Kakugo virus (KV; Sacbrood virus (SBV; Black Queen cell virus (BQCV; Acute bee paralysis virus (ABPV; Kashmir bee virus (KBV; Israeli Acute Paralysis Virus (IAPV; Chronic bee paralysis virus (CBPV. The review has been designed to provide researchers in the field with updated information about honeybee viruses and to serve as a starting point for future research.

  19. Virus Infections of Honeybees Apis Mellifera

    Science.gov (United States)

    Tantillo, Giuseppina; Bottaro, Marilisa; Di Pinto, Angela; Martella, Vito; Di Pinto, Pietro

    2015-01-01

    The health and vigour of honeybee colonies are threatened by numerous parasites (such as Varroa destructor and Nosema spp.) and pathogens, including viruses, bacteria, protozoa. Among honeybee pathogens, viruses are one of the major threats to the health and well-being of honeybees and cause serious concern for researchers and beekeepers. To tone down the threats posed by these invasive organisms, a better understanding of bee viral infections will be of crucial importance in developing effective and environmentally benign disease control strategies. Here we summarize recent progress in the understanding of the morphology, genome organization, transmission, epidemiology and pathogenesis of eight honeybee viruses: Deformed wing virus (DWV) and Kakugo virus (KV); Sacbrood virus (SBV); Black Queen cell virus (BQCV); Acute bee paralysis virus (ABPV); Kashmir bee virus (KBV); Israeli Acute Paralysis Virus (IAPV); Chronic bee paralysis virus (CBPV). The review has been designed to provide researchers in the field with updated information about honeybee viruses and to serve as a starting point for future research. PMID:27800411

  20. Pathogenesis of hepatitis B virus infection

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Infection with hepatitis B virus (HBV) leads to a wide spectrum of clinical presentations ranging from an asymptomatic carrier state to self-limited acute or fulminant hepatitis to chronic hepatitis with progression to cirrhosis and hepatocellular carcinoma. Infection with HBV is one of the most common viral diseases affecting man. Both viral factors as well as the host immune response have been implicated in the pathogenesis and clinical outcome of HBV infection. In this review, we will discuss the impact of virus-host interactions for the pathogenesis of HBV infection and liver disease. These interactions include the relevance of naturally occurring viral variants for clinical disease, the role of virus-induced apoptosis for HBV-induced liver cell injury and the impact of antiviral immune responses for outcome of infection.

  1. Virus Infection-Induced Bronchial Asthma Exacerbation

    Directory of Open Access Journals (Sweden)

    Mutsuo Yamaya

    2012-01-01

    Full Text Available Infection with respiratory viruses, including rhinoviruses, influenza virus, and respiratory syncytial virus, exacerbates asthma, which is associated with processes such as airway inflammation, airway hyperresponsiveness, and mucus hypersecretion. In patients with viral infections and with infection-induced asthma exacerbation, inflammatory mediators and substances, including interleukins (ILs, leukotrienes and histamine, have been identified in the airway secretions, serum, plasma, and urine. Viral infections induce an accumulation of inflammatory cells in the airway mucosa and submucosa, including neutrophils, lymphocytes and eosinophils. Viral infections also enhance the production of inflammatory mediators and substances in airway epithelial cells, mast cells, and other inflammatory cells, such as IL-1, IL-6, IL-8, GM-CSF, RANTES, histamine, and intercellular adhesion molecule-1. Viral infections affect the barrier function of the airway epithelial cells and vascular endothelial cells. Recent reports have demonstrated augmented viral production mediated by an impaired interferon response in the airway epithelial cells of asthma patients. Several drugs used for the treatment of bronchial asthma reduce viral and pro-inflammatory cytokine release from airway epithelial cells infected with viruses. Here, I review the literature on the pathogenesis of the viral infection-induced exacerbation of asthma and on the modulation of viral infection-induced airway inflammation.

  2. DIESEL EXHAUST ENHANCES INFLUENZA VIRUS INFECTIONS IN RESPIRATORY EPITHELIAL CELLS

    Science.gov (United States)

    Several factors, such as age and nutritional status can affect the susceptibility to influenza infections. Moreover, exposure to air pollutants, such as diesel exhaust (DE), has been shown to affect respiratory virus infections in rodent models. Influenza virus primarily infects ...

  3. High prevalence of occult hepatitis C virus infection in patients with chronic hepatitis B virus infection.

    Science.gov (United States)

    Castillo, Inmaculada; Bartolomé, Javier; Quiroga, Juan Antonio; Carreño, Vicente

    2013-08-01

    Hepatitis C virus (HCV) infection in the absence of detectable antibodies against HCV and of viral RNA in serum is called occult HCV infection. Its prevalence and clinical significance in chronic hepatitis B virus (HBV) infection is unknown. HCV RNA was tested for in the liver samples of 52 patients with chronic HBV infection and 21 (40 %) of them were positive for viral RNA (occult HCV infection). Liver fibrosis was found more frequently and the fibrosis score was significantly higher in patients with occult HCV than in negative ones, suggesting that occult HCV infection may have an impact on the clinical course of HBV infection.

  4. Controversies about occult hepatitis B virus infection

    Institute of Scientific and Technical Information of China (English)

    Ersan Ozaslan; Tugrul Purnak

    2009-01-01

    We read with great interest the paper written by Shi et al, reviewing the molecular characteristics and stages of chronic hepatitis B virus (HBV) infection. We think that some points in the definition of occult HBV infection (OBI) and their conclusion about the management of OBI may need further considerations.

  5. Neuralgic amyotrophy and hepatitis E virus infection

    NARCIS (Netherlands)

    J.J.J. van Eijk (Jeroen); R.G. Madden (Richie); A.A. Eijck (Annemiek); J.G. Hunter (Jeremy); J.H.J. Reimerink (Johan); R.P. Bendall (Richard); S.D. Pas (Suzan); V. Ellis (Vic); N. van Alfen (Nens); L. Beynon (Laura); L. Southwell (Lucy); B. McLean (Brendan); B.C. Jacobs (Bart); B.G.M. van Engelen (Baziel); H.R. Dalton (Harry)

    2014-01-01

    textabstractObjective: To determine whether there is an association between an acute preceding hepatitis E virus (HEV) infection and neuralgic amyotrophy (NA), and if so, whether patients with HEV-related NA differ from patients without an associated HEV infection. Methods: HEV testing was conducted

  6. Neuralgic amyotrophy and hepatitis E virus infection

    NARCIS (Netherlands)

    Eijk, J.J.J. van; Madden, R.G.; Eijk, A.A. van der; Hunter, J.G.; Reimerink, J.H.; Bendall, R.P.; Pas, S.D.; Ellis, V.; Alfen, N. van; Beynon, L.; Southwell, L.; McLean, B.; Jacobs, B.C.; Engelen, B.G.M. van; Dalton, H.R.

    2014-01-01

    OBJECTIVE: To determine whether there is an association between an acute preceding hepatitis E virus (HEV) infection and neuralgic amyotrophy (NA), and if so, whether patients with HEV-related NA differ from patients without an associated HEV infection. METHODS: HEV testing was conducted in a retros

  7. Inhibition of enveloped viruses infectivity by curcumin.

    Directory of Open Access Journals (Sweden)

    Tzu-Yen Chen

    Full Text Available Curcumin, a natural compound and ingredient in curry, has antiinflammatory, antioxidant, and anticarcinogenic properties. Previously, we reported that curcumin abrogated influenza virus infectivity by inhibiting hemagglutination (HA activity. This study demonstrates a novel mechanism by which curcumin inhibits the infectivity of enveloped viruses. In all analyzed enveloped viruses, including the influenza virus, curcumin inhibited plaque formation. In contrast, the nonenveloped enterovirus 71 remained unaffected by curcumin treatment. We evaluated the effects of curcumin on the membrane structure using fluorescent dye (sulforhodamine B; SRB-containing liposomes that mimic the viral envelope. Curcumin treatment induced the leakage of SRB from these liposomes and the addition of the influenza virus reduced the leakage, indicating that curcumin disrupts the integrity of the membranes of viral envelopes and of liposomes. When testing liposomes of various diameters, we detected higher levels of SRB leakage from the smaller-sized liposomes than from the larger liposomes. Interestingly, the curcumin concentration required to reduce plaque formation was lower for the influenza virus (approximately 100 nm in diameter than for the pseudorabies virus (approximately 180 nm and the vaccinia virus (roughly 335 × 200 × 200 nm. These data provide insights on the molecular antiviral mechanisms of curcumin and its potential use as an antiviral agent for enveloped viruses.

  8. Prevalence and prognostic significance of infection with TT virus in patients infected with human immunodeficiency virus

    DEFF Research Database (Denmark)

    Christensen, JK; Eugen-Olsen, Jesper; Sørensen, M;

    2000-01-01

    No clear association between human disease and TT virus (TTV) has been documented. A possible pathogenic role of TTV was investigated in patients infected with human immunodeficiency virus (HIV). TTV serum concentrations were estimated in 185 HIV-infected patients by dilution polymerase chain...

  9. Epstein-Barr virus infection mechanisms

    Institute of Scientific and Technical Information of China (English)

    Liudmila S. Chesnokova; Lindsey M. Hutt-Fletcher

    2014-01-01

    Epstein-Barr virus (EBV) infection occurs by distinct mechanisms across different cell types. EBV infection of B cellsin vitro minimally requires 5 viral glycoproteins and 2 cellular proteins. By contrast, infection of epithelial cells requires a minimum of 3 viral glycoproteins, which are capable of interacting with one or more of 3 different celular proteins. The ful complement of proteins involved in entry into al cel types capable of being infectedin vivo is unknown. This review discusses the events that occur when the virus is delivered into the cytoplasm of a cel, the players known to be involved in these events, and the ways in which these players are thought to function.

  10. Immune Response to Ebola Virus Infection

    Directory of Open Access Journals (Sweden)

    Alain Alonso Remedios

    2016-06-01

    Full Text Available Ebola virus belongs to the family Filoviridae and causes a highly lethal hemorrhagic fever. Affected patients show an impaired immune response as a result of the evasion mechanisms employed by the virus. Cathepsin is an enzyme present in the granules of phagocytes which cleaves viral surface glycoproteins, allowing virus entry into the host cell. In addition, this virus is resistant to the antiviral effects of type I interferon, promotes the synthesis of proinflammatory cytokines and induces apoptosis of monocytes and lymphocytes. It also induces an incomplete activation of dendritic cells, thus avoiding the presentation of viral antigens. Although specific antibodies are produced after the first week, their neutralizing capacity is doubtful. The virus evades the immune response and replicates uncontrollably in the host. This paper aims to summarize the main characteristics of the immune response to Ebola virus infection.

  11. Autoimmune pathogenesis in dengue virus infection.

    Science.gov (United States)

    Lin, Chiou-Feng; Wan, Shu-Wen; Cheng, Hsien-Jen; Lei, Huan-Yao; Lin, Yee-Shin

    2006-01-01

    The pathogenic mechanisms of dengue hemorrhagic fever and dengue shock syndrome (DHF/DSS) caused by dengue virus (DV) infection remain unresolved. Patients with DHF/DSS are characterized by several manifestations, including severe thrombocytopenia, vascular leakage, and hepatomegaly. In addition to the effect of virus load and virus variation, abnormal immune responses of the host after DV infection may also account for the progression of DHF/DSS. Actually, viral autoimmunity is involved in the pathogenesis of numerous viral infections, such as human immunodeficiency virus, human hepatitis C virus, human cytomegalovirus, herpes simplex virus, Epstein- Barr virus, and DV. In this review, we discuss the implications of autoimmunity in dengue pathogenesis. Antibodies directed against DV nonstructural protein 1 (NS1) showed cross-reactivity with human platelets and endothelial cells, which lead to platelet and endothelial cell damage and inflammatory activation. Based on these findings, we hypothesize that anti-DV NS1 is involved in the pathogenesis of DF and DHF/DSS, and this may provide important information in dengue vaccine development.

  12. Interferon-γ Inhibits Ebola Virus Infection

    OpenAIRE

    2015-01-01

    Ebola virus outbreaks, such as the 2014 Makona epidemic in West Africa, are episodic and deadly. Filovirus antivirals are currently not clinically available. Our findings suggest interferon gamma, an FDA-approved drug, may serve as a novel and effective prophylactic or treatment option. Using mouse-adapted Ebola virus, we found that murine interferon gamma administered 24 hours before or after infection robustly protects lethally-challenged mice and reduces morbidity and serum viral titers. F...

  13. [Extrahepatic manifestations of hepatitis C virus infection].

    Science.gov (United States)

    Roca, Bernardino

    2004-10-01

    Hepatitis C virus predominantly affects the liver, although it may also produce a number of extrahepatic manifestations, such as mixed cryoglobulinemia, salivary and lacrimal gland dysfunction, and several types of kidney disease. The pathogenesis of these conditions is not completely understood, but immunologic mechanisms are involved in many cases. In some patients with hepatitis C virus infection, the extrahepatic manifestations predominate and their proper diagnosis and management is very important.

  14. Multiple infections of rodents with zoonotic pathogens in Austria.

    Science.gov (United States)

    Schmidt, Sabrina; Essbauer, Sandra S; Mayer-Scholl, Anne; Poppert, Sven; Schmidt-Chanasit, Jonas; Klempa, Boris; Henning, Klaus; Schares, Gereon; Groschup, Martin H; Spitzenberger, Friederike; Richter, Dania; Heckel, Gerald; Ulrich, Rainer G

    2014-07-01

    Rodents are important reservoirs for a large number of zoonotic pathogens. We examined the occurrence of 11 viral, bacterial, and parasitic agents in rodent populations in Austria, including three different hantaviruses, lymphocytic choriomeningitis virus, orthopox virus, Leptospira spp., Borrelia spp., Rickettsia spp., Bartonella spp., Coxiella burnetii, and Toxoplasma gondii. In 2008, 110 rodents of four species (40 Clethrionomys glareolus, 29 Apodemus flavicollis, 26 Apodemus sylvaticus, and 15 Microtus arvalis) were trapped at two rural sites in Lower Austria. Chest cavity fluid and samples of lung, spleen, kidney, liver, brain, and ear pinna skin were collected. We screened selected tissue samples for hantaviruses, lymphocytic choriomeningitis virus, orthopox viruses, Leptospira, Borrelia, Rickettsia, Bartonella spp., C. burnetii, and T. gondii by RT-PCR/PCR and detected nucleic acids of Tula hantavirus, Leptospira spp., Borrelia afzelii, Rickettsia spp., and different Bartonella species. Serological investigations were performed for hantaviruses, lymphocytic choriomeningitis virus, orthopox viruses, and Rickettsia spp. Here, Dobrava-Belgrade hantavirus-, Tula hantavirus-, lymphocytic choriomeningitis virus-, orthopox virus-, and rickettsia-specific antibodies were demonstrated. Puumala hantavirus, C. burnetii, and T. gondii were neither detected by RT-PCR/PCR nor by serological methods. In addition, multiple infections with up to three pathogens were shown in nine animals of three rodent species from different trapping sites. In conclusion, these results show that rodents in Austria may host multiple zoonotic pathogens. Our observation raises important questions regarding the interactions of different pathogens in the host, the countermeasures of the host's immune system, the impact of the host-pathogen interaction on the fitness of the host, and the spread of infectious agents among wild rodents and from those to other animals or humans.

  15. Effect of attenuated viral vaccines on suckling mice infected with LCMV.

    Science.gov (United States)

    Csatáry, L K; Szeri, I; Bános, Z; Anderlik, P; Nász, I

    1986-01-01

    A single intraperitoneal treatment with live Newcastle Disease Virus (NDV) containing attenuated NDV vaccine, and with live infectious bursal disease virus (IBDV) containing attenuated IBDV vaccine, one day before intracerebral infection with lymphocytic choriomeningitis virus (LCMV) increased, whereas a similar treatment with inactivated NDV or IBDV vaccine did not influence the death rate of suckling mice from experimental lymphocytic choriomeningitis. Thus the attenuated live vaccine stimulated, whereas the inactivated ones failed to affect the cell-mediated immune response to LCMV. Control studies set up with the supernatant of plain tissue culture routinely used for the propagation of IBDV have shown that unlike the attenuated NDV vaccine, the immunostimulatory action is associated not so much with the virus itself, as with an as yet unidentified component of the tissue culture supernatant.

  16. Immune responses and Lassa virus infection.

    Science.gov (United States)

    Russier, Marion; Pannetier, Delphine; Baize, Sylvain

    2012-11-05

    Lassa fever is a hemorrhagic fever endemic to West Africa and caused by Lassa virus, an Old World arenavirus. It may be fatal, but most patients recover from acute disease and some experience asymptomatic infection. The immune mechanisms associated with these different outcomes have not yet been fully elucidated, but considerable progress has recently been made, through the use of in vitro human models and nonhuman primates, the only relevant animal model that mimics the pathophysiology and immune responses induced in patients. We discuss here the roles of the various components of the innate and adaptive immune systems in Lassa virus infection and in the control of viral replication and pathogenesis.

  17. Antibody-Dependent Enhancement of Marburg Virus Infection

    OpenAIRE

    Nakayama, Eri; Tomabechi, Daisuke; Matsuno, Keita; Kishida, Noriko; Yoshida, Reiko; Feldmann, Heinz; Takada, Ayato

    2011-01-01

    Background. Marburg virus (MARV) and Ebola virus (EBOV) cause severe hemorrhagic fever in primates. Earlier studies demonstrated that antibodies to particular epitopes on the glycoprotein (GP) of EBOV enhanced virus infectivity in vitro.

  18. Plant virus infections control stomatal development

    Science.gov (United States)

    Murray, Rose R.; Emblow, Mark S. M.; Hetherington, Alistair M.; Foster, Gary D.

    2016-09-01

    Stomata are important regulators of carbon dioxide uptake and transpirational water loss. They also represent points of vulnerability as bacterial and fungal pathogens utilise this natural opening as an entry portal, and thus have an increasingly complex relationship. Unlike the situation with bacterial and fungal pathogens, we know very little about the role of stomata in viral infection. Here we report findings showing that viral infection influences stomatal development in two susceptible host systems (Nicotiana tabacum with TMV (Tobacco mosaic virus), and Arabidopsis thaliana with TVCV (Turnip vein-clearing virus)), but not in resistant host systems (Nicotiana glutinosa and Chenopodium quinoa with TMV). Virus infected plants had significantly lower stomatal indices in systemic leaves of susceptible systems; N. tabacum 9.8% reduction and A. thaliana 12.3% reduction, but not in the resistant hosts. Stomatal density in systemic leaves was also significantly reduced in virus infected A. thaliana by 19.6% but not in N. tabacum or the resistant systems. In addition, transpiration rate was significantly reduced in TMV infected N. tabacum.

  19. Plant virus infections control stomatal development

    Science.gov (United States)

    Murray, Rose R.; Emblow, Mark S. M.; Hetherington, Alistair M.; Foster, Gary D.

    2016-01-01

    Stomata are important regulators of carbon dioxide uptake and transpirational water loss. They also represent points of vulnerability as bacterial and fungal pathogens utilise this natural opening as an entry portal, and thus have an increasingly complex relationship. Unlike the situation with bacterial and fungal pathogens, we know very little about the role of stomata in viral infection. Here we report findings showing that viral infection influences stomatal development in two susceptible host systems (Nicotiana tabacum with TMV (Tobacco mosaic virus), and Arabidopsis thaliana with TVCV (Turnip vein-clearing virus)), but not in resistant host systems (Nicotiana glutinosa and Chenopodium quinoa with TMV). Virus infected plants had significantly lower stomatal indices in systemic leaves of susceptible systems; N. tabacum 9.8% reduction and A. thaliana 12.3% reduction, but not in the resistant hosts. Stomatal density in systemic leaves was also significantly reduced in virus infected A. thaliana by 19.6% but not in N. tabacum or the resistant systems. In addition, transpiration rate was significantly reduced in TMV infected N. tabacum. PMID:27687773

  20. Hepatitis C virus infection and risk of coronary artery disease

    DEFF Research Database (Denmark)

    Roed, Torsten; Lebech, Anne-Mette; Kjaer, Andreas;

    2012-01-01

    Several chronic infections have been associated with cardiovascular diseases, including Chlamydia pneumoniae, human immunodeficiency virus and viral hepatitis. This review evaluates the literature on the association between chronic hepatitis C virus (HCV) infection and the risk of coronary artery...

  1. USEFULNESS OF THE GRAPEVINE VIRUS-INFECTED COLLECTION

    Directory of Open Access Journals (Sweden)

    Elena-Cocuţa Buciumeanu

    2012-04-01

    Full Text Available In order to use the virus-infected material as reference in various studies, a grapevine virus collection was established at NRDIBH Ştefănşti-Argeş. The vines are infected with 1-3 of the main specific viruses of this crop: fanleaf virus, leafroll associated virus serotypes 1+3, fleck virus and virus A. Different lots of plants belonging to the same cultivar are infected with different viruses. The own rooted or grafted potted plants are maintained in an insect-proof greenhouse. The main goals of the study of grapevine under the influence of virus infection had in view: symptoms, in vitro behaviour of virus infected grapevine, virus elimination, plant positive control in the diagnostic process. The symptoms produced by viral infection can affect the whole plant (systemic symptoms or they are visible on certain parts of the plant (local symptoms. In vitro studies of virus infected grapevines comparatively with the healthy material aimed with the quantitative and qualitative aspects of the culture: multiplication and rooting rates, shoots elongation, abnormal cuttings and vitrification phenomena. Infected grapevine cultivars and clones were subjected to virus elimination through thermotherapy, chemotherapy or electrotherapy, combined with in vitro culture. The diagnosis of leafroll, fleck, vein necrosis and corky bark diseases have been done by in vitro micrografting, as rapid biological method of virus detection. Samples collected from infected vines were used as material testing for virus detection by ELISA in inter-laboratory comparisons and Iaboratory-performed validation.

  2. Severe Thrombocytopenia after Zika Virus Infection, Guadeloupe, 2016

    Science.gov (United States)

    Boyer Chammard, Timothée; Schepers, Kinda; Breurec, Sébastien; Messiaen, Thierry; Destrem, Anne-Laure; Mahevas, Matthieu; Soulillou, Adrien; Janaud, Ludovic; Curlier, Elodie; Herrmann-Storck, Cécile

    2017-01-01

    Severe thrombocytopenia during or after the course of Zika virus infection has been rarely reported. We report 7 cases of severe thrombocytopenia and hemorrhagic signs and symptoms in Guadeloupe after infection with this virus. Clinical course and laboratory findings strongly suggest a causal link between Zika virus infection and immune-mediated thrombocytopenia. PMID:27997330

  3. Infection of Plants by Tobacco Mosaic Virus.

    Science.gov (United States)

    McDaniel, Larry; Maratos, Marina; Farabaugh, Joan

    1998-01-01

    Provides three exercises that introduce high school and college students to a common strain of the tobacco mosaic virus and the study of some basic biological processes. Activities involve inoculation of plants and observing and recording symptom development in infected plants. (DDR)

  4. Neopterin and human immunodeficiency virus infection

    DEFF Research Database (Denmark)

    Hofmann, B

    1993-01-01

    to predict the later development of AIDS. The increased neopterin concentrations show that the immune system is activated in HIV infection and demonstrate the presence of an interaction between the virus and the immune system. The most important future use of neopterin measurements may be in fast evaluation...

  5. Extrahepatic manifestations of hepatitis C virus infection.

    Science.gov (United States)

    Zignego, Anna Linda; Craxì, Antonio

    2008-08-01

    Hepatitis C virus may cause hepatic and extrahepatic diseases. Extrahepatic manifestations range from disorders for which a significant association with viral infection is supported by epidemiologic and pathogenetic data, to anecdotal observations without clear proof of causality. This article describes the diagnosis and treatment of these diseases.

  6. Previous infection with a mesogenic strain of Newcastle disease virus affects infection with highly pathogenic avian influenza viruses in chickens

    Science.gov (United States)

    Avian influenza virus (AIV) and Newcastle disease virus (NDV) are two of the most important viruses affecting poultry worldwide, but little is known on the interactions between these two viruses when infecting birds. In a previous study we found that infection of chickens with a mesogenic strain of...

  7. Immunodomination during peripheral vaccinia virus infection.

    Directory of Open Access Journals (Sweden)

    Leon C W Lin

    Full Text Available Immunodominance is a fundamental property of CD8(+ T cell responses to viruses and vaccines. It had been observed that route of administration alters immunodominance after vaccinia virus (VACV infection, but only a few epitopes were examined and no mechanism was provided. We re-visited this issue, examining a panel of 15 VACV epitopes and four routes, namely intradermal (i.d., subcutaneous (s.c., intraperitoneal (i.p. and intravenous (i.v. injection. We found that immunodominance is sharpened following peripheral routes of infection (i.d. and s.c. compared with those that allow systemic virus dissemination (i.p. and i.v.. This increased immunodominance was demonstrated with native epitopes of VACV and with herpes simplex virus glycoprotein B when expressed from VACV. Responses to some subdominant epitopes were altered by as much as fourfold. Tracking of virus, examination of priming sites, and experiments restricting virus spread showed that priming of CD8(+ T cells in the spleen was necessary, but not sufficient to broaden responses. Further, we directly demonstrated that immunodomination occurs more readily when priming is mainly in lymph nodes. Finally, we were able to reduce immunodominance after i.d., but not i.p. infection, using a VACV expressing the costimulators CD80 (B7-1 and CD86 (B7-2, which is notable because VACV-based vaccines incorporating these molecules are in clinical trials. Taken together, our data indicate that resources for CD8(+ T cell priming are limiting in local draining lymph nodes, leading to greater immunodomination. Further, we provide evidence that costimulation can be a limiting factor that contributes to immunodomination. These results shed light on a possible mechanism of immunodomination and highlight the need to consider multiple epitopes across the spectrum of immunogenicities in studies aimed at understanding CD8(+ T cell immunity to viruses.

  8. Immunobiology of Ebola and Lassa virus infections.

    Science.gov (United States)

    Prescott, Joseph B; Marzi, Andrea; Safronetz, David; Robertson, Shelly J; Feldmann, Heinz; Best, Sonja M

    2017-03-01

    Two of the most important contemporary emerging viruses that affect human health in Africa are Ebola virus (EBOV) and Lassa virus (LASV). The 2013-2016 West African outbreak of EBOV was responsible for more than 11,000 deaths, primarily in Guinea, Sierra Leone and Liberia. LASV is constantly emerging in these and surrounding West African countries, with an estimate of more than 500,000 cases of Lassa fever, and approximately 5,000 deaths, annually. Both EBOV and LASV are zoonotic, and human infection often results in a severe haemorrhagic fever in both cases. However, the contribution of specific immune responses to disease differs between EBOV and LASV. This Review examines innate and adaptive immune responses to these viruses with the goal of delineating responses that are associated with protective versus pathogenic outcomes.

  9. Update on oral herpes virus infections.

    Science.gov (United States)

    Balasubramaniam, Ramesh; Kuperstein, Arthur S; Stoopler, Eric T

    2014-04-01

    Oral herpes virus infections (OHVIs) are among the most common mucosal disorders encountered by oral health care providers. These infections can affect individuals at any age, from infants to the elderly, and may cause significant pain and dysfunction. Immunosuppressed patients may be at increased risk for serious and potential life-threatening complications caused by OHVIs. Clinicians may have difficulty in diagnosing these infections because they can mimic other conditions of the oral mucosa. This article provides oral health care providers with clinically relevant information regarding etiopathogenesis, diagnosis, and management of OHVIs.

  10. Prevalence of occult hepatitis B virus infection

    Institute of Scientific and Technical Information of China (English)

    Maria Luisa Gutiérrez-García; Conrado M Fernandez-Rodriguez; Jose Luis Lledo-Navarro; Ingrid Buhigas-Garcia

    2011-01-01

    Occult hepatitis B virus (HBV) infection (OBI) is characterized by the persistence of HBV DNA in the liver tissue in individuals negative for the HBV surface antigen. The prevalence of OBI is quite variable depending on the level of endemic disease in different parts of the world,the different assays utilized in the studies, and the different populations studied. Many studies have been carried out on OBI prevalence in different areas of the world and categories of individuals. The studies show that OBI prevalence seems to be higher among subjects at high risk for HBV infection and with liver disease than among individuals at low risk of infection and without liver disease.

  11. Hepatitis C virus infection in the human immunodeficiency virus infected patient

    DEFF Research Database (Denmark)

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

    2014-01-01

    Human immunodeficiency virus (HIV) and hepatitis C virus (HCV) share the same transmission routes; therefore, coinfection is frequent. An estimated 5-10 million individuals alone in the western world are infected with both viruses. The majority of people acquire HCV by injection drug use and...... for 15%-20% of chronically infected individuals. HCV treatment has rapidly changed with the development of new direct-acting antiviral agents; therefore, cure rates have greatly improved because the new treatment regimens target different parts of the HCV life cycle. In this review, we focus...

  12. Hepatitis C virus infection and apoptosis

    Institute of Scientific and Technical Information of China (English)

    Richard Fischer; Thomas Baumert; Hubert E Blum

    2007-01-01

    Apoptosis is central for the control and elimination of viral infections. In chronic hepatitis C virus (HCV) infection,enhanced hepatocyte apoptosis and upregulation of the death inducing ligands CD95/Fas, TRAIL and TNFα occur.Nevertheless, HCV infection persists in the majority of patients. The impact of apoptosis in chronic HCV infection is not well understood. It may be harmful by triggering liver fibrosis, or essential in interferon (IFN)induced HCV elimination. For virtually all HCV proteins,pro- and anti-apoptotic effects have been described,especially for the core and NS5A protein. To date, it is not known which HCV protein affects apoptosis in vivo and whether the infectious virions act pro- or antiapoptotic. With the availability of an infectious tissue culture system, we now can address pathophysiologically relevant issues. This review focuses on the effect of HCV infection and different HCV proteins on apoptosis and of the corresponding signaling cascades.

  13. [Hepatitis C virus infection and alcohol].

    Science.gov (United States)

    Campollo, Octavio

    2002-10-01

    It was thought that HCV infection was very frequent among alcoholics; some even though that this disease affected nearly 35% of this group. Now there seems to be a consensus among the main investigator groups that the correlation of hepatitis C and alcohol increases the risk of complications, cirrhosis and liver cancer included. Moreover, it's now certain that among patients with HCV infection, alcohol consumption increases the risk of death from live diseases during the first 10 years of the disease. Alcoholism is also considered a predisposing factor for HCV infection, but not for hepatitis B virus infection. Prospective studies about post-transfusional hepatitis C showed the risk of cirrhosis increases from 7.8 to 31.1 times if the patient consumed significant amounts of alcohol (> 80 g a day). One of the recommendations for every patient with HCV infection is to abstain from drinking alcohol.

  14. Avian Influenza: Mixed Infections and Missing Viruses

    Directory of Open Access Journals (Sweden)

    David E. Wentworth

    2013-08-01

    Full Text Available A high prevalence and diversity of avian influenza (AI viruses were detected in a population of wild mallards sampled during summer 2011 in California, providing an opportunity to compare results obtained before and after virus culture. We tested cloacal swab samples prior to culture by matrix real-time PCR, and by amplifying and sequencing a 640bp portion of the hemagglutinin (HA gene. Each sample was also inoculated into embryonated chicken eggs, and full genome sequences were determined for cultured viruses. While low matrix Ct values were a good predictor of virus isolation from eggs, samples with high or undetectable Ct values also yielded isolates. Furthermore, a single passage in eggs altered the occurrence and detection of viral strains, and mixed infections (different HA subtypes were detected less frequently after culture. There is no gold standard or perfect reference comparison for surveillance of unknown viruses, and true negatives are difficult to distinguish from false negatives. This study showed that sequencing samples prior to culture increases the detection of mixed infections and enhances the identification of viral strains and sequences that may have changed or even disappeared during culture.

  15. Avian influenza: mixed infections and missing viruses.

    Science.gov (United States)

    Lindsay, LeAnn L; Kelly, Terra R; Plancarte, Magdalena; Schobel, Seth; Lin, Xudong; Dugan, Vivien G; Wentworth, David E; Boyce, Walter M

    2013-08-05

    A high prevalence and diversity of avian influenza (AI) viruses were detected in a population of wild mallards sampled during summer 2011 in California, providing an opportunity to compare results obtained before and after virus culture. We tested cloacal swab samples prior to culture by matrix real-time PCR, and by amplifying and sequencing a 640bp portion of the hemagglutinin (HA) gene. Each sample was also inoculated into embryonated chicken eggs, and full genome sequences were determined for cultured viruses. While low matrix Ct values were a good predictor of virus isolation from eggs, samples with high or undetectable Ct values also yielded isolates. Furthermore, a single passage in eggs altered the occurrence and detection of viral strains, and mixed infections (different HA subtypes) were detected less frequently after culture. There is no gold standard or perfect reference comparison for surveillance of unknown viruses, and true negatives are difficult to distinguish from false negatives. This study showed that sequencing samples prior to culture increases the detection of mixed infections and enhances the identification of viral strains and sequences that may have changed or even disappeared during culture.

  16. Cells in Dengue Virus Infection In Vivo

    Directory of Open Access Journals (Sweden)

    Sansanee Noisakran

    2010-01-01

    Full Text Available Dengue has been recognized as one of the most important vector-borne emerging infectious diseases globally. Though dengue normally causes a self-limiting infection, some patients may develop a life-threatening illness, dengue hemorrhagic fever (DHF/dengue shock syndrome (DSS. The reason why DHF/DSS occurs in certain individuals is unclear. Studies in the endemic regions suggest that the preexisting antibodies are a risk factor for DHF/DSS. Viremia and thrombocytopenia are the key clinical features of dengue virus infection in patients. The amounts of virus circulating in patients are highly correlated with severe dengue disease, DHF/DSS. Also, the disturbance, mainly a transient depression, of hematological cells is a critical clinical finding in acute dengue patients. However, the cells responsible for the dengue viremia are unresolved in spite of the intensive efforts been made. Dengue virus appears to replicate and proliferate in many adapted cell lines, but these in vitro properties are extremely difficult to be reproduced in primary cells or in vivo. This paper summarizes reports on the permissive cells in vitro and in vivo and suggests a hematological cell lineage for dengue virus infection in vivo, with the hope that a new focus will shed light on further understanding of the complexities of dengue disease.

  17. Neutralizing antibodies in hepatitis C virus infection

    Institute of Scientific and Technical Information of China (English)

    Mirjam B Zeisel; Samira Fafi-Kremer; Isabel Fofana; Heidi Barth; Fran(c)oise Stoll-Keller; Michel Doffo(e)l; Thomas F Baumert

    2007-01-01

    Hepatitis C virus (HCV) is a major cause of hepatitis world-wide. The majority of infected individuals develop chronic hepatitis which can then progress to liver cirrhosis and hepatocellular carcinoma. Spontaneous viral clearance occurs in about 20%-30% of acutely infected individuals and results in resolution of infection without sequaelae. Both viral and host factors appear to play an important role for resolution of acute infection. A large body of evidence suggests that a strong, multispecific and long-lasting cellular immune response appears to be important for control of viral infection in acute hepatitis C. Due too the lack of convenient neutralization assays,the impact of neutralizing responses for control of viral infection had been less defined. In recent years, the development of robust tissue culture model systems for HCV entry and infection has finally allowed study of antibody-mediated neutralization and to gain further insights into viral targets of host neutralizing responses.In addition, detailed analysis of antibody-mediated neutralization in individual patients as well as cohorts with well defined viral isolates has enabled the study of neutralizing responses in the course of HCV infection and characterization of the impact of neutralizing antibodies for control of viral infection. This review will summarize recent progress in the understanding of the molecular mechanisms of antibody-mediated neutralization and its impact for HCV pathogenesis.(C) 2007 The WJG Press. All rights reserved.

  18. Zebrafish: modeling for herpes simplex virus infections.

    Science.gov (United States)

    Antoine, Thessicar Evadney; Jones, Kevin S; Dale, Rodney M; Shukla, Deepak; Tiwari, Vaibhav

    2014-02-01

    For many years, zebrafish have been the prototypical model for studies in developmental biology. In recent years, zebrafish has emerged as a powerful model system to study infectious diseases, including viral infections. Experiments conducted with herpes simplex virus type-1 in adult zebrafish or in embryo models are encouraging as they establish proof of concept with viral-host tropism and possible screening of antiviral compounds. In addition, the presence of human homologs of viral entry receptors in zebrafish such as 3-O sulfated heparan sulfate, nectins, and tumor necrosis factor receptor superfamily member 14-like receptor bring strong rationale for virologists to test their in vivo significance in viral entry in a zebrafish model and compare the structure-function basis of virus zebrafish receptor interaction for viral entry. On the other end, a zebrafish model is already being used for studying inflammation and angiogenesis, with or without genetic manipulations, and therefore can be exploited to study viral infection-associated pathologies. The major advantage with zebrafish is low cost, easy breeding and maintenance, rapid lifecycle, and a transparent nature, which allows visualizing dissemination of fluorescently labeled virus infection in real time either at a localized region or the whole body. Further, the availability of multiple transgenic lines that express fluorescently tagged immune cells for in vivo imaging of virus infected animals is extremely attractive. In addition, a fully developed immune system and potential for receptor-specific knockouts further advocate the use of zebrafish as a new tool to study viral infections. In this review, we focus on expanding the potential of zebrafish model system in understanding human infectious diseases and future benefits.

  19. A winning war against hepatitis B virus infection in China

    Institute of Scientific and Technical Information of China (English)

    JIA Ji-dong; ZHUANG Hui

    2007-01-01

    @@ Hepatitis B virus (HBV) infection is a worldwide health problem.According to WHO estimation,about 2 billion people globally have been infected With HBV and 350 million of them have chronic HBV infection.1

  20. [A NEW PANDEMIC: ZIKA VIRUS INFECTION].

    Science.gov (United States)

    Bourée, Patrice

    2016-06-01

    Zika virus is a flavivirus isolated in non human primates in 1647, then in humans 1954 (Uganda). It emerged on Micronesia (island af Yap) in 2007, then in French Polynesia in 2013-2014, in South America (mostly in Brazil and Colombia) in 2015 and in French West Indies in 2016. It is transmitted by the bite of Aedes mosquitoes. Zika virus infection is symptomatic in only 20% of cases and clinical presentation is associated with mild illness. But several neurological complications are reported (as Guillain-Barré syndrome: 48 cases in French Polynesia) and congenital malformations (microcephaly). Laboratory diagnosis is based on virus isolation by PCR. There is no specific treatment or vaccine available against the Zika virs. Prevention is based on measures of protection from mosquitoes bites.

  1. Myeloradiculopathy associated with chikungunya virus infection.

    Science.gov (United States)

    Bank, Anna M; Batra, Ayush; Colorado, Rene A; Lyons, Jennifer L

    2016-02-01

    Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that is endemic to parts of Africa, South and Southeast Asia, and more recently the Caribbean. Patients typically present with fever, rash, and arthralgias, though neurologic symptoms, primarily encephalitis, have been described. We report the case of a 47-year-old woman who was clinically diagnosed with CHIKV while traveling in the Dominican Republic and presented 10 days later with left lower extremity weakness, a corresponding enhancing thoracic spinal cord lesion, and positive CHIKV serologies. She initially responded to corticosteroids, followed by relapsing symptoms and gradual clinical improvement. The time lapse between acute CHIKV infection and the onset of myelopathic sequelae suggests an immune-mediated phenomenon rather than direct activity of the virus itself. Chikungunya virus should be considered in the differential diagnosis of myelopathy in endemic areas. The progression of symptoms despite corticosteroid administration suggests more aggressive immunomodulatory therapies may be warranted at disease onset.

  2. Epidemiology of hepatitis C virus infection

    Institute of Scientific and Technical Information of China (English)

    Miriam J Alter

    2007-01-01

    Globally, hepatitis C virus (HCV) has infected an estimated 130 million people, most of whom are chronically infected. HCV-infected people serve as a reservoir for transmission to others and are at risk for developing chronic liver disease, cirrhosis, and primary hepatocellular carcinoma (HCC). It has been estimated that HCV accounts for 27% of cirrhosis and 25% of HCC worldwide. HCV infection has likely been endemic in many populations for centuries. However, the wave of increased HCV-related morbidity and mortality that we are now facing is the result of an unprecedented increase in the spread of HCV during the 20th century.Two 20th century events appear to be responsible for this increase; the widespread availability of injectable therapies and the illicit use of injectable drugs.

  3. Immune Responses and Lassa Virus Infection

    Directory of Open Access Journals (Sweden)

    Sylvain Baize

    2012-11-01

    Full Text Available Lassa fever is a hemorrhagic fever endemic to West Africa and caused by Lassa virus, an Old World arenavirus. It may be fatal, but most patients recover from acute disease and some experience asymptomatic infection. The immune mechanisms associated with these different outcomes have not yet been fully elucidated, but considerable progress has recently been made, through the use of in vitro human models and nonhuman primates, the only relevant animal model that mimics the pathophysiology and immune responses induced in patients. We discuss here the roles of the various components of the innate and adaptive immune systems in Lassa virus infection and in the control of viral replication and pathogenesis.

  4. Human immunodeficiency virus infection in adolescents.

    Science.gov (United States)

    Lehmann, Corinne; D'Angelo, Lawrence J

    2010-08-01

    Despite advances in human immunodeficiency virus (HIV) treatment and discovery of effective prevention programs, HIV infection in American youth continues to rise, especially in minority youth. The crisis underscores the lack of access to care and wellness of our adolescent and young adult populations. Primary care practitioners who care for young adults will diagnose and/or encounter HIV-infected patients in their practice. Providers need to become familiar with the basics of HIV prevention and treatment, as well as how adolescence presents unique challenges in HIV care.

  5. Animal Models of Varicella Zoster Virus Infection

    Directory of Open Access Journals (Sweden)

    Ilhem Messaoudi

    2013-05-01

    Full Text Available Primary infection with varicella zoster virus (VZV results in varicella (chickenpox followed by the establishment of latency in sensory ganglia. Declining T cell immunity due to aging or immune suppressive treatments can lead to VZV reactivation and the development of herpes zoster (HZ, shingles. HZ is often associated with significant morbidity and occasionally mortality in elderly and immune compromised patients. There are currently two FDA-approved vaccines for the prevention of VZV: Varivax® (for varicella and Zostavax® (for HZ. Both vaccines contain the live-attenuated Oka strain of VZV. Although highly immunogenic, a two-dose regimen is required to achieve a 99% seroconversion rate. Zostavax vaccination reduces the incidence of HZ by 51% within a 3-year period, but a significant reduction in vaccine-induced immunity is observed within the first year after vaccination. Developing more efficacious vaccines and therapeutics requires a better understanding of the host response to VZV. These studies have been hampered by the scarcity of animal models that recapitulate all aspects of VZV infections in humans. In this review, we describe different animal models of VZV infection as well as an alternative animal model that leverages the infection of Old World macaques with the highly related simian varicella virus (SVV and discuss their contributions to our understanding of pathogenesis and immunity during VZV infection.

  6. Mechanisms of Zika Virus Infection and Neuropathogenesis.

    Science.gov (United States)

    Olagnier, David; Muscolini, Michela; Coyne, Carolyn B; Diamond, Michael S; Hiscott, John

    2016-08-01

    A spotlight has been focused on the mosquito-borne Zika virus (ZIKV) because of its epidemic outbreak in Brazil and Latin America, as well as the severe neurological manifestations of microcephaly and Guillain-Barré syndrome associated with infection. In this review, we discuss the recent literature on ZIKV-host interactions, including new mechanistic insight concerning the basis of ZIKV-induced neuropathogenesis.

  7. Immune Responses and Lassa Virus Infection

    OpenAIRE

    Sylvain Baize; Marion Russier; Delphine Pannetier

    2012-01-01

    Lassa fever is a hemorrhagic fever endemic to West Africa and caused by Lassa virus, an Old World arenavirus. It may be fatal, but most patients recover from acute disease and some experience asymptomatic infection. The immune mechanisms associated with these different outcomes have not yet been fully elucidated, but considerable progress has recently been made, through the use of in vitro human models and nonhuman primates, the only relevant animal model that mimics the pathophysiology and i...

  8. Autoimmune Diseases Co-Existing with Hepatitis C Virus Infection

    Directory of Open Access Journals (Sweden)

    Zohreh Jadali

    2010-12-01

    Full Text Available Autoimmunity and viral infections are closely associated fields, and viruses have been proposed as a likely aetiological, contributory or triggering factors of systemic autoimmune diseases. Hepatitis C virus seems to be the virus usually associated with the appearance of autoimmune diseases, and the relationship between chronic hepatitis C virus infection and some autoimmune disease has been studied. For some of these disorders their association with hepatitis C virus infection is well recognized while for others it remains probable or weak. Examples of autoimmune phenomena observed in chronic hepatitis C virus infection include rheumatoid arthritis, thyroid disease, cryoglobulinaemia, immune thrombocytopenic purpura, systemic lupus erythematosus and sjogren syndrome. To date, the etiological role and the pathogenetic involvement of the hepatitis C infection remains unknown.The aim of this study is to assess the presence of different autoimmune manifestations of hepatitis C virus infection reported in literature.

  9. Vaccinia virus infections in martial arts gym, Maryland, USA, 2008.

    Science.gov (United States)

    Hughes, Christine M; Blythe, David; Li, Yu; Reddy, Ramani; Jordan, Carol; Edwards, Cindy; Adams, Celia; Conners, Holly; Rasa, Catherine; Wilby, Sue; Russell, Jamaal; Russo, Kelly S; Somsel, Patricia; Wiedbrauk, Danny L; Dougherty, Cindy; Allen, Christopher; Frace, Mike; Emerson, Ginny; Olson, Victoria A; Smith, Scott K; Braden, Zachary; Abel, Jason; Davidson, Whitni; Reynolds, Mary; Damon, Inger K

    2011-04-01

    Vaccinia virus is an orthopoxvirus used in the live vaccine against smallpox. Vaccinia virus infections can be transmissible and can cause severe complications in those with weakened immune systems. We report on a cluster of 4 cases of vaccinia virus infection in Maryland, USA, likely acquired at a martial arts gym.

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

    Energy Technology Data Exchange (ETDEWEB)

    Straus, S.E. (National Institute of Allergy and Infectious Diseases, Bethesda, MD (USA))

    1989-12-01

    The major features that distinguish recurrent herpes simplex virus infections from zoster are illustrated in this article by two case histories. The clinical and epidemiologic features that characterize recurrent herpes simplex virus and varicella-zoster virus infections are reviewed. It is noted that herpesvirus infections are more common and severe in patients with cellular immune deficiency. Each virus evokes both humoral and cellular immune response in the course of primary infection. DNA hybridization studies with RNA probes labelled with sulfur-35 indicate that herpes simplex viruses persist within neurons, and that varicella-zoster virus is found in the satellite cells that encircle the neurons.

  11. Orthopox virus infections in Eurasian wild rodents.

    Science.gov (United States)

    Kinnunen, Paula M; Henttonen, Heikki; Hoffmann, Bernd; Kallio, Eva R; Korthase, Christian; Laakkonen, Juha; Niemimaa, Jukka; Palva, Airi; Schlegel, Mathias; Ali, Hanan Sheikh; Suominen, Paula; Ulrich, Rainer G; Vaheri, Antti; Vapalahti, Olli

    2011-08-01

    The genus Orthopoxvirus includes variola (smallpox) virus and zoonotic cowpox virus (CPXV). All orthopoxviruses (OPV) are serologically cross-reactive and cross-protective, and after the cessation of smallpox vaccination, CPXV and other OPV infections represent an emerging threat to human health. In this respect CPXV, with its reservoir in asymptomatically infected wild rodents, is of special importance. In Europe, clinical cowpox has been diagnosed in both humans and animals. The main objective of this study was to elucidate the prevalence of OPV infections in wild rodents in different parts of Eurasia and to compare the performance of three real-time polymerase chain reaction (PCR) methods in detecting OPV DNA in wildlife samples. We investigated 962 wild rodents from Northern Europe (Finland), Central Europe (Germany), and Northern Asia (Siberia, Russia) for the presence of OPV antibodies. According to a CPXV antigen-based immunofluorescence assay, animals from 13 of the 17 locations (76%) showed antibodies. Mean seroprevalence was 33% in Finland (variation between locations 0%-69%), 32% in Germany (0%-43%), and 3.2% (0%-15%) in Siberia. We further screened tissue samples from 513 of the rodents for OPV DNA using up to three real-time PCRs. Three rodents from two German and one Finnish location were OPV DNA positive. The amplicons were 96% to 100% identical to available CPXV sequences. Further, we demonstrated OPV infections as far east as the Baikal region and occurring in hamster and two other rodent species, ones previously unnoticed as possible reservoir hosts. Based on serological and PCR findings, Eurasian wild rodents are frequently but nonpersistently infected with OPVs. Results from three real-time PCR methods were highly concordant. This study extends the geographic range and wildlife species diversity in which OPV (or CPXV) viruses are naturally circulating.

  12. Significance of blood analysis in hemophiliacs co-infected with human immunodeficiency virus and hepatitis viruses

    Institute of Scientific and Technical Information of China (English)

    Fang Shen; Qin Huang; Hong-Qing Sun; Reena Ghildyal

    2007-01-01

    AIM:To study the effect of hepatitis virus infection on cirrhosis and liver function markers in HIV-infected hemophiliacs.METHODS:We have analyzed the immunological,liver function and cirrhosis markers in a cohort of hemophiliacs co-infected with human immunodeficiency virus (HIV) and hepatitis viruses.RESULTS:There was no difference in immunological markers among co-infected patients and patients infected with HIV only and those co-infected with one or more hepatitis virus. Although liver function and cirrhosis markers remained within a normal range,there was a worsening trend in all patients co-infected with hepatitis virus C (HCV),which was further exacerbated in the presence of additional infection with hepatitis virus B (HBV).CONCLUSION:Co-infection with HIV,HBV and HCV leads to worsening of hyaluronic acid and liver function markers. Increases in serum hyaluronic acid may be suggestive of a predisposition to liver diseases.

  13. Human immunodeficiency virus infection, Part II.

    Science.gov (United States)

    Horowitz, H W; Telzak, E E; Sepkowitz, K A; Wormser, G P

    1998-12-01

    The acceptance of highly active antiretroviral therapy (HAART) among patients and health care providers has had a dramatic impact on the epidemiology and clinical characteristics of many opportunistic infections associated with human immunodeficiency virus (HIV). Previously intractable opportunistic infections and syndromes are now far less common. In addition, effective antibiotic prophylactic therapies have had a profound impact on the risk of patients developing particular infections and on the incidence of these infections overall. Most notable among these are Pneumocystis carinii, disseminated Mycobacterium avium complex, tuberculosis, and toxoplasmosis. Nevertheless, infections continue to cause significant morbidity and mortality among patients who are infected with HIV. The role of HAART in many clinical situations is unquestioned. Compelling data from clinical trials support the use of these therapies during pregnancy to prevent perinatal transmission of HIV. HAART is also recommended for health care workers who have had a "significant" exposure to the blood of an HIV-infected patient. Both of these situations are discussed in detail in this article. In addition, although more controversial, increasing evidence supports the use of HAART during the acute HIV seroconversion syndrome. An "immune reconstitution syndrome" has been newly described for patients in the early phases of treatment with HAART who develop tuberculosis, M avium complex, and cytomegalovirus disease. Accumulating data support the use of hydroxyurea, an agent with a long history in the field of myeloproliferative disorders, for the treatment of HIV. Newer agents, particularly abacavir and adefovir dipivoxil, are available through expanded access protocols, and their roles are being defined and clarified.

  14. Hepatitis E Virus (HEV) Infection in Ireland

    LENUS (Irish Health Repository)

    Hickey, C

    2016-09-01

    Hepatitis E virus (HEV) is a single stranded RNA virus causing infection worldwide. In developing countries HEV genotypes 1 and 2 spread faeco-orally via water. Recently, infections with HEV have been detected in Europe and North America in patients with no travel history. These are food-borne HEV genotypes 3 and 4, a pig-associated zoonosis. Most infections are asymptomatic but morbidity and chronic infection may occur with prior liver disease or immunosuppression. International seroprevalence rates vary and with improved diagnostics have increased. To determine the current prevalence in this region we studied anonymised serum samples submitted in 2015 for routine testing. We detected anti-HEV IgG in 16\\/198 (8%) individuals, highest rate in 40-59 year olds (43.8%). This is higher than reported for the same region in 1995 (0.4%) using a previous generation assay. This study provides evidence of HEV circulation in Ireland and reinforces the need for ongoing surveillance.

  15. KINETIC PROFILE OF INFLUENZA VIRUS INFECTION IN THREE RAT STRAINS

    Science.gov (United States)

    AbstractInfluenza infection is a respiratory disease of viral origin that can cause major epidemics in man. The influenza virus infects and damages epithelial cells of the respiratory tract and causes pneumonia. Lung lesions of mice infected with influenza virus resembl...

  16. Ação do radium sôbre o vírus da Coriomeningite linfocitária benigna Radium effect upon the lymphocytic choriomeningitis virus

    Directory of Open Access Journals (Sweden)

    J. Guilherme Lacorte

    1968-01-01

    Full Text Available O presente trabalho faz parte de uma seqüência iniciada em 1953 com a verificação do efeito dos raios X sôbre o vírus da gripe em que observamos que os mesmos, em doses fracas, tem aumentado o seu poder patogênico para camundongos. Posteriormente, verificamos a ação do radium sôbre o vírus da gripe e da poliomielite. Neste último caso, o vírus irradiado mostrou-se ativo durante maior número de dias. Nas pesquisas aqui referidas, submetemos o vírus da coriomeningite linfocitária benigna a ação do radium, usando quatro agulhas de 1 mg desse elemento em dispositivo que idealizamos para êste fim. Depois de irradiada, foi a suspensão de vírus diluida a 10*-1, 10*-2 e 10*-3 para as inoculações em camundongos, juntamente com as diluições testemunhas. Observamos que o vírus resistiu pelo menos 264 dias, à temperatura de 4ºC. Quanto às alterações do poder patogênico provocadas pelo radium verificamos que o mesmo não se altera após 24 horas de irradiação. Diminue após 8 dias para aumentar, de modo seguro, após 20 e 33 dias. Iguala-se ao testemunha depois de 78 dias.In the present paper the authors refered the experiments made with the lymphocytic chriomeningitis virus. We strain, after exposition to 4 tubes of 1 mg of radium. The virus suspension was put into the Carrel flask in a layer of 0,1 cm. The titrations of the irradiated virus suspension were made after 24 hours, 8, 20, 33, 78, 85, 120, 264, 292, 387 and 535 days. the virus was still active after 264 days, not after 292 days. The virus irradiated during 24 hours presented the same pathogenicity form mice than the control but after 8 days it was lesser and after 20 and 33 days it was enchanced (Graphic 10. After 78 days the pathogenic power was the same for the irradiated virus and the control.

  17. Treatment of hepatitis C virus infection

    Institute of Scientific and Technical Information of China (English)

    Kilian Weigand; Wolfgang Stremmel; Jens Encke

    2007-01-01

    Acute and chronic hepatitis C virus (HCV) infection remains a serious health problem worldwide, however,there has been advancement in the treatment of HCV infection due to standard treatment using pegylated interferon and ribavirin. The literature indicates that therapy for HCV is becoming more individualized. In addition to considering genotype and viral RNA levels before treatment, achievement of an early virologic response (EVR) and a rapid virologic response (RVR) is now possible during therapy. Moreover, problem patients,such as non-responders, relapsers, HIV or HBV coinfected patients, patients with liver cirrhosis, and preor post-liver transplantation patients are an increasing fraction of the patients requiring treatment. This article reviews the literature regarding standard treatments and problem patients with acute and chronic HCV infection.It also includes discussion on contraindications and side effects of treatment with interferon and ribavirin, as well as new drug development.

  18. First Imported Case of Zika Virus Infection into Korea

    OpenAIRE

    Jang, Hee-Chang; Park, Wan Beom; Kim, Uh Jin; Chun, June Young; Choi, Su-jin; Choe, Pyoeng Gyun; Jung, Sook-In; Jee, Youngmee; Kim, Nam Joong; Choi, Eun Hwa; Oh, Myoung-Don

    2016-01-01

    Since Zika virus has been spreading rapidly in the Americas from 2015, the outbreak of Zika virus infection becomes a global health emergency because it can cause neurological complications and adverse fetal outcome including microcephaly. Here, we report clinical manifestations and virus isolation findings from a case of Zika virus infection imported from Brazil. The patient, 43-year-old Korean man, developed fever, myalgia, eyeball pain, and maculopapular rash, but not neurological manifest...

  19. Bilateral optic neuritis in acute human immunodeficiency virus infection

    DEFF Research Database (Denmark)

    Larsen, M; Toft, P.B.; Bernhard, P;

    1998-01-01

    PURPOSE: To report a case of acute viral disease accompanied by bilateral optic neuritis with substantial paraclinical evidence that human immunodeficiency virus was the causative agent. METHODS: Clinical and paraclinical examination. Magnetic resonance imaging. RESULTS: Virus and antibody titers...... as well as reverse lymphocytosis were consistent with acute infection by the human immunodeficiency virus-1. CONCLUSIONS: Human immunodeficiency virus infection should be considered in the differential diagnosis of acute optic neuritis...

  20. Imunocompetent Mice Model for Dengue Virus Infection

    Directory of Open Access Journals (Sweden)

    Denise Gonçalves

    2012-01-01

    Full Text Available Dengue fever is a noncontagious infectious disease caused by dengue virus (DENV. DENV belongs to the family Flaviviridae, genus Flavivirus, and is classified into four antigenically distinct serotypes: DENV-1, DENV-2, DENV-3, and DENV-4. The number of nations and people affected has increased steadily and today is considered the most widely spread arbovirus (arthropod-borne viral disease in the world. The absence of an appropriate animal model for studying the disease has hindered the understanding of dengue pathogenesis. In our study, we have found that immunocompetent C57BL/6 mice infected intraperitoneally with DENV-1 presented some signs of dengue disease such as thrombocytopenia, spleen hemorrhage, liver damage, and increase in production of IFNγ and TNFα cytokines. Moreover, the animals became viremic and the virus was detected in several organs by real-time RT-PCR. Thus, this animal model could be used to study mechanism of dengue virus infection, to test antiviral drugs, as well as to evaluate candidate vaccines.

  1. Chaperones in hepatitis C virus infection

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    The hepatitis C virus (HCV) infects approximately 3% ofthe world population or more than 185 million peopleworldwide. Each year, an estimated 350000-500000deaths occur worldwide due to HCV-associated diseasesincluding cirrhosis and hepatocellular carcinoma. HCV isthe most common indication for liver transplantation inpatients with cirrhosis worldwide. HCV is an envelopedRNA virus classified in the genus Hepacivirus in theFlaviviridae family. The HCV viral life cycle in a cellcan be divided into six phases (1) binding and internalization;(2) cytoplasmic release and uncoating; (3)viral polyprotein translation and processing; (4) RNAgenome replication; (5) encapsidation (packaging) andassembly; and (6) virus morphogenesis (maturation)and secretion. Many host factors are involved in theHCV life cycle. Chaperones are an important group ofhost cytoprotective molecules that coordinate numerouscellular processes including protein folding, multimericprotein assembly, protein trafficking, and proteindegradation. All phases of the viral life cycle requirechaperone activity and the interaction of viral proteinswith chaperones. This review will present our currentknowledge and understanding of the role of chaperonesin the HCV life cycle. Analysis of chaperones in HCVinfection will provide further insights into viral/hostinteractions and potential therapeutic targets for bothHCV and other viruses.

  2. Acute Human Inkoo and Chatanga Virus Infections, Finland.

    Science.gov (United States)

    Putkuri, Niina; Kantele, Anu; Levanov, Lev; Kivistö, Ilkka; Brummer-Korvenkontio, Markus; Vaheri, Antti; Vapalahti, Olli

    2016-05-01

    Inkoo virus (INKV) and Chatanga virus (CHATV), which are circulating in Finland, are mosquitoborne California serogroup orthobunyaviruses that have a high seroprevalence among humans. Worldwide, INKV infection has been poorly described, and CHATV infection has been unknown. Using serum samples collected in Finland from 7,961 patients suspected of having viral neurologic disease or Puumala virus infection during the summers of 2001-2013, we analyzed the samples to detect California serogroup infections. IgM seropositivity revealed 17 acute infections, and cross-neutralization tests confirmed presence of INKV or CHATV infections. All children (<16 years of age) with INKV infection were hospitalized; adults were outpatients with mild disease, except for 1 who was hospitalized with CHATV infection. Symptoms included fever, influenza-like illness, nausea or vomiting, disorientation, nuchal rigidity, headache, drowsiness, and seizures. Although many INKV and CHATV infections appear to be subclinical, these viruses can cause more severe disease, especially in children.

  3. Immunological alterations in hepatitis C virus infection.

    Science.gov (United States)

    Calvaruso, Vincenza; Craxì, Antonio

    2013-12-21

    A higher prevalence of immunological processes has recently been reported in patients with hepatitis C virus (HCV) infection, focusing the attention of physicians and researchers on the close association between HCV and immune disorders. HCV lymphotropism represents the most important step in the pathogenesis of virus-related immunological diseases and experimental, virologic, and clinical evidence has demonstrated a trigger role for HCV both in systemic autoimmune diseases, such as rheumatoid arthritis, Sjögren syndrome, hemolytic anemia and severe thrombocytopenia, and in organ-specific autoimmune diseases, such as autoimmune hepatitis, thyroid disorders and diabetes. This review will outline the principal aspects of such HCV-induced immunological alterations, focusing on the prevalence of these less characterized HCV extrahepatic manifestations.

  4. H5N6 influenza virus infection, the newest influenza

    Institute of Scientific and Technical Information of China (English)

    Beuy; Joob; Wiwanitkit; Viroj

    2015-01-01

    The most recent new emerging infection is the H5N6 inl uenza virus infection. This infection has just been reported from China in early May 2014. The disease is believed to be a cross species infection. All indexed cases are from China. Of interest, the H5N6 inl uenza virus is the primary virus for avian. The avian H5N6 inl uenza virus in avian population is a low virulent strain. However, the clinical manifestation in human seems severe. In this mini-review, the authors summarize and discuss on this new emerging inl uenza.

  5. H5N6 influenza virus infection, the newest influenza

    Directory of Open Access Journals (Sweden)

    Beuy Joob

    2015-06-01

    Full Text Available The most recent new emerging infection is the H5N6 influenza virus infection. This infection has just been reported from China in early May 2014. The disease is believed to be a cross species infection. All indexed cases are from China. Of interest, the H5N6 influenza virus is the primary virus for avian. The avian H5N6 influenza virus in avian population is a low virulent strain. However, the clinical manifestation in human seems severe. In this mini-review, the authors summarize and discuss on this new emerging influenza.

  6. Hepatitis B virus and hepatitis C virus infection inhealthcare workers

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    Approximately 3 million healthcare workers per yearreceive an injury with an occupational instrument, witharound 2000000 exposures to hepatitis B virus (HBV)and 1000000 to hepatitis C virus (HCV). Although aneffective HBV vaccine has been available since theearly eighties, and despite the worldwide applicationof universal vaccination programs started in the earlynineties, HBV still remains a prominent agent of morbidityand mortality. There is no vaccine to limit thediffusion of HCV infection, which progresses to chronicityin the majority of cases and is a major cause of morbidityand mortality worldwide due to a chronic liverdisease. Healthcare workers are frequently exposed by amucosal-cutaneous or percutaneous route to accidentalcontact with human blood and other potentially infectiousbiological materials while carrying out their occupationalduties. Mucosal-cutaneous exposure occurswhen the biological material of a potentially infectedpatient accidentally comes in contact with the mucousmembranes of the eyes or mouth or with the skin of ahealthcare worker. Percutaneous exposure occurs whenan operator accidentally injures himself with a sharpcontaminated object, like a needle, blade or other sharpmedical instrument. About 75% of the total occupationalexposure is percutaneous and 25% mucosal-cutaneous,the risk of infecting a healthcare worker being higherin percutaneous than in mucosal-cutaneous exposure.All healthcare workers should be considered for HBVvaccination and should meticulously apply the universalprophylactic measures to prevent exposure to HBV andHCV.

  7. Update on occult hepatitis B virus infection

    Science.gov (United States)

    Makvandi, Manoochehr

    2016-01-01

    The event of mutations in the surface antigen gene of hepatitis B virus (HBV) results in undetectable hepatitis B surface antigen with positive/negative anti-hepatitis B core (anti-HBc) antibody status in serum and this phenomenon is named occult hepatitis B infection (OBI). The presence of anti-HBc antibody in serum is an important key for OBI tracking, although about 20% of OBI cases are negative for anti-HBc antibody. The diagnosis of OBI is mainly based on polymerase chain reaction (PCR) and real-time PCR assays. However, real-time PCR is a more reliable method than PCR. OBI is a great issue for the public health problem and a challenge for the clinical entity worldwide. The persistence of OBI may lead to the development of cirrhosis and hepatocellular carcinoma. With regard to OBI complications, the screening of HBV DNA by the highly sensitive molecular means should be implemented for: (1) patients with a previous history of chronic or acute HBV infection; (2) patients co-infected with hepatitis C virus/human immunodeficiency virus; (3) patients undergoing chemotherapy or anti-CD20 therapy; (4) recipients of organ transplant; (5) blood donors; (6) organ transplant donors; (7) thalassemia and hemophilia patients; (8) health care workers; (9) patients with liver related disease (cryptogenic); (10) hemodialysis patients; (11) patients undergoing lamivudine or interferon therapy; and (12) children in time of HBV vaccination especially in highly endemic areas of HBV. Active HBV vaccination should be implemented for the close relatives of patients who are negative for OBI markers. Thus, the goal of this review is to evaluate the rate of OBI with a focus on status of high risk groups in different regions of the world. PMID:27818588

  8. Sofosbuvir treatment and hepatitis C virus infection

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    Hepatitis C virus (HCV) infection is a serious problemworldwide. The use of interferon-based therapy hasmade HCV eradication challenging. The recent appearanceof direct-acting antiviral agents (DAAs) haschanged HCV therapy. Combining the use of DAAs withpeginterferon and ribavirin has improved treatmentefficacy. Furthermore, the combination of different orallyadministered DAAs has enabled interferon-free therapywith much higher efficacy and safety. In particular,sofosbuvir, a nucleotide-based NS5B inhibitor, preventsHCV RNA synthesis by acting as a "chain terminator".Treatment with sofosbuvir has attained an extremelyhigh rate of sustained virologic response. The currentreview summarizes the efficacy and safety of sofosbuvirtherapy.

  9. The ecology of viruses that infect eukaryotic algae.

    Science.gov (United States)

    Short, Steven M

    2012-09-01

    Because viruses of eukaryotic algae are incredibly diverse, sweeping generalizations about their ecology are rare. These obligate parasites infect a range of algae and their diversity can be illustrated by considering that isolates range from small particles with ssRNA genomes to much larger particles with 560 kb dsDNA genomes. Molecular research has also provided clues about the extent of their diversity especially considering that genetic signatures of algal viruses in the environment rarely match cultivated viruses. One general concept in algal virus ecology that has emerged is that algal viruses are very host specific and most infect only certain strains of their hosts; with the exception of viruses of brown algae, evidence for interspecies infectivity is lacking. Although some host-virus systems behave with boom-bust oscillations, complex patterns of intraspecies infectivity can lead to host-virus coexistence obfuscating the role of viruses in host population dynamics. Within the framework of population dynamics, host density dependence is an important phenomenon that influences virus abundances in nature. Variable burst sizes of different viruses also influence their abundances and permit speculations about different life strategies, but as exceptions are common in algal virus ecology, life strategy generalizations may not be broadly applicable. Gaps in knowledge of virus seasonality and persistence are beginning to close and investigations of environmental reservoirs and virus resilience may answer questions about virus inter-annual recurrences. Studies of algal mortality have shown that viruses are often important agents of mortality reinforcing notions about their ecological relevance, while observations of the surprising ways viruses interact with their hosts highlight the immaturity of our understanding. Considering that just two decades ago algal viruses were hardly acknowledged, recent progress affords the optimistic perspective that future studies

  10. High numbers of IL-2-producing CD8+ T cells during viral infection: correlation with stable memory development

    DEFF Research Database (Denmark)

    Kristensen, Nanna Ny; Christensen, Jan Pravsgaard; Thomsen, Allan Randrup

    2002-01-01

    Using infections with lymphocytic choriomeningitis virus (LCMV) and vesicular stomatitis virus in mice as model systems, we have investigated the ability of antigen-primed CD8+ T cells generated in the context of viral infections to produce IL-2. Our results indicate that acute immunizing infection...... normally leads to generation of high numbers of IL-2-producing antigen-specific CD8+ T cells. By costaining for IL-2 and IFN-gamma intracellularly, we found that IL-2-producing cells predominantly constitute a subset of cells also producing IFN-gamma. Comparison of the kinetics of generation revealed...

  11. Zika virus infections in pregnancy: epidemics and case management

    Directory of Open Access Journals (Sweden)

    Fatih sahiner

    2016-03-01

    Full Text Available Zika virus is an RNA virus belonging to the Flaviviridae family, and is primarily transmitted by Aedes mosquitoes. Only a small number of cases had been described until 2007 when the first major Zika virus outbreak occurred on Yap Island, Micronesia. Approximately 80% of people infected with Zika virus do not exhibit any symptoms. Symptomatic infections are generally moderate and characterized by acute onset of fever, maculopapular rash, arthralgia, or conjunctivitis. The virus has recently attracted a broad interest due to the emerging cases of microcephaly that are possibly associated with mothers infected by the Zika virus during pregnancy, and the regional increases in the incidence of Guillain-Barre syndrome during the epidemic periods. Although the relationship between Zika virus infection and these abnormalities is not obviously understood yet, Zika virus testing is recommended for infants with microcephaly or intracranial calcifications whose mothers were potentially infected with the Zika virus during pregnancy. Every day, new reports are being published about the outbreaks associated with this virus; nevertheless, no new cases of this virus have been reported in Turkey. Despite this, we cannot currently exclude the possibility of the encounter with the virus because of the presence of Aedes mosquitoes, which are responsible for the spread of the virus, are prevalent in Turkey, and an increasing number of travel-related cases are being reported from different countries. In the light of the current knowledge on this virus, this review aims to discuss the course of Zika virus infections in detail, especially congenital infection, and presenting current information about the case management and preventive measures. [Cukurova Med J 2016; 41(1.000: 143-151

  12. Hepatitis B virus infection in Indonesia

    Science.gov (United States)

    Yano, Yoshihiko; Utsumi, Takako; Lusida, Maria Inge; Hayashi, Yoshitake

    2015-01-01

    Approximately 240 million people are chronically infected with hepatitis B virus (HBV), 75% of whom reside in Asia. Approximately 600000 of infected patients die each year due to HBV-related diseases or hepatocellular carcinoma (HCC). The endemicity of hepatitis surface antigen in Indonesia is intermediate to high with a geographical difference. The risk of HBV infection is high in hemodialysis (HD) patients, men having sex with men, and health care workers. Occult HBV infection has been detected in various groups such as blood donors, HD patients, and HIV-infected individuals and children. The most common HBV subgenotype in Indonesia is B3 followed by C1. Various novel subgenotypes of HBV have been identified throughout Indonesia, with the novel HBV subgenotypes C6-C16 and D6 being successfully isolated. Although a number of HBV subgenotypes have been discovered in Indonesia, genotype-related pathogenicity has not yet been elucidated in detail. Therefore, genotype-related differences in the prognosis of liver disease and their effects on treatments need to be determined. A previous study conducted in Indonesia revealed that hepatic steatosis was associated with disease progression. Pre-S2 mutations and mutations at C1638T and T1753V in HBV/B3 have been associated with advanced liver diseases including HCC. However, drug resistance to lamivudine, which is prominent in Indonesia, remains obscure. Although the number of studies on HBV in Indonesia has been increasing, adequate databases on HBV infection are limited. We herein provided an overview of the epidemiology and clinical characteristics of HBV infection in Indonesia. PMID:26478663

  13. Encephalomyocarditis virus infection in an Italian zoo

    Directory of Open Access Journals (Sweden)

    Pascotto Ernesto

    2010-03-01

    Full Text Available Abstract A fatal Encephalomyocarditis virus (EMCV infection epidemic involving fifteen primates occurred between October 2006 and February 2007 at the Natura Viva Zoo. This large open-field zoo park located near Lake Garda in Northern Italy hosts one thousand animals belonging to one hundred and fifty different species, including various lemur species. This lemur collection is the most relevant and rich in Italy. A second outbreak between September and November 2008 involved three lemurs. In all cases, the clinical signs were sudden deaths generally without any evident symptoms or only with mild unspecific clinical signs. Gross pathologic changes were characterized by myocarditis (diffuse or focal pallor of the myocardium, pulmonary congestion, emphysema, oedema and thoracic fluid. The EMCV was isolated and recognized as the causative agent of both outbreaks. The first outbreak in particular was associated with a rodent plague, confirming that rats are an important risk factor for the occurrence of the EMCV infection.

  14. Spatiotemporal Dynamics of Virus Infection Spreading in Tissues

    Science.gov (United States)

    Meyerhans, Andreas; Bessonov, Nickolai; Trofimchuk, Sergei; Volpert, Vitaly

    2016-01-01

    Virus spreading in tissues is determined by virus transport, virus multiplication in host cells and the virus-induced immune response. Cytotoxic T cells remove infected cells with a rate determined by the infection level. The intensity of the immune response has a bell-shaped dependence on the concentration of virus, i.e., it increases at low and decays at high infection levels. A combination of these effects and a time delay in the immune response determine the development of virus infection in tissues like spleen or lymph nodes. The mathematical model described in this work consists of reaction-diffusion equations with a delay. It shows that the different regimes of infection spreading like the establishment of a low level infection, a high level infection or a transition between both are determined by the initial virus load and by the intensity of the immune response. The dynamics of the model solutions include simple and composed waves, and periodic and aperiodic oscillations. The results of analytical and numerical studies of the model provide a systematic basis for a quantitative understanding and interpretation of the determinants of the infection process in target organs and tissues from the image-derived data as well as of the spatiotemporal mechanisms of viral disease pathogenesis, and have direct implications for a biopsy-based medical testing of the chronic infection processes caused by viruses, e.g. HIV, HCV and HBV. PMID:27997613

  15. Honey Bee Infecting Lake Sinai Viruses

    Directory of Open Access Journals (Sweden)

    Katie F. Daughenbaugh

    2015-06-01

    Full Text Available Honey bees are critical pollinators of important agricultural crops. Recently, high annual losses of honey bee colonies have prompted further investigation of honey bee infecting viruses. To better characterize the recently discovered and very prevalent Lake Sinai virus (LSV group, we sequenced currently circulating LSVs, performed phylogenetic analysis, and obtained images of LSV2. Sequence analysis resulted in extension of the LSV1 and LSV2 genomes, the first detection of LSV4 in the US, and the discovery of LSV6 and LSV7. We detected LSV1 and LSV2 in the Varroa destructor mite, and determined that a large proportion of LSV2 is found in the honey bee gut, suggesting that vector-mediated, food-associated, and/or fecal-oral routes may be important for LSV dissemination. Pathogen-specific quantitative PCR data, obtained from samples collected during a small-scale monitoring project, revealed that LSV2, LSV1, Black queen cell virus (BQCV, and Nosema ceranae were more abundant in weak colonies than strong colonies within this sample cohort. Together, these results enhance our current understanding of LSVs and illustrate the importance of future studies aimed at investigating the role of LSVs and other pathogens on honey bee health at both the individual and colony levels.

  16. Honey Bee Infecting Lake Sinai Viruses.

    Science.gov (United States)

    Daughenbaugh, Katie F; Martin, Madison; Brutscher, Laura M; Cavigli, Ian; Garcia, Emma; Lavin, Matt; Flenniken, Michelle L

    2015-06-23

    Honey bees are critical pollinators of important agricultural crops. Recently, high annual losses of honey bee colonies have prompted further investigation of honey bee infecting viruses. To better characterize the recently discovered and very prevalent Lake Sinai virus (LSV) group, we sequenced currently circulating LSVs, performed phylogenetic analysis, and obtained images of LSV2. Sequence analysis resulted in extension of the LSV1 and LSV2 genomes, the first detection of LSV4 in the US, and the discovery of LSV6 and LSV7. We detected LSV1 and LSV2 in the Varroa destructor mite, and determined that a large proportion of LSV2 is found in the honey bee gut, suggesting that vector-mediated, food-associated, and/or fecal-oral routes may be important for LSV dissemination. Pathogen-specific quantitative PCR data, obtained from samples collected during a small-scale monitoring project, revealed that LSV2, LSV1, Black queen cell virus (BQCV), and Nosema ceranae were more abundant in weak colonies than strong colonies within this sample cohort. Together, these results enhance our current understanding of LSVs and illustrate the importance of future studies aimed at investigating the role of LSVs and other pathogens on honey bee health at both the individual and colony levels.

  17. 78 FR 33848 - Draft Guidance for Industry on Human Immunodeficiency Virus-1 Infection: Developing...

    Science.gov (United States)

    2013-06-05

    ... No. FDA-2013-D-0589] Draft Guidance for Industry on Human Immunodeficiency Virus-1 Infection... guidance for industry entitled ``Human Immunodeficiency Virus-1 Infection: Developing Antiretroviral Drugs... guidance for industry entitled ``Human Immunodeficiency Virus-1 Infection: Developing Antiretroviral...

  18. Hepatitis B virus infection in immigrant populations

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Hepatitis B virus (HBV) is the most common cause ofhepatitis worldwide, with nearly 350 million peoplechronically infected and 600000 deaths per year dueto acute liver failure occurring during acute hepatitisor, more frequently, in HBV-related liver cirrhosis orhepatocellular carcinoma. Ongoing immigration fromcountries with a high HBV endemicity to those with a lowHBV endemicity warrants particular attention to preventthe spread of HBV infection to the native population.This review article analyzes the epidemiology andvirological and clinical characteristics of HBV infectionin immigrant populations and in their host countries,and suggests prophylactic measures to prevent thespread of this infection. Among the immigrants fromdifferent geographical areas, those from South East Asiaand sub-Saharan Africa show the highest prevalencesof hepatitis B surface antigen (HBsAg) carriers, inaccordance with the high endemicity of the countriesof origin. The molecular characteristics of HBV infectionin immigrants reflect those of the geographical areasof origin HBV genotype A and D predominate inimmigrants from Eastern Europe, B and C in those fromAsia and genotype E in those from Africa. The literaturedata on the clinical course and treatment of HBsAgpositiveimmigrants are scanty. The management ofHBV infection in immigrant populations is difficult andrequires expert personnel and dedicated structures fortheir assistance. The social services, voluntary operatorsand cultural mediators are essential to achieve optimizedpsychological and clinical intervention.

  19. Hepatitis C Virus Infection and Mixed Cryoglobulinemia

    Directory of Open Access Journals (Sweden)

    Gianfranco Lauletta

    2012-01-01

    Full Text Available Hepatitis C virus (HCV chronic infection is recognized as the major cause of mixed cryoglobulinemia (MC. Its persistence represents a continuous stimulus for host immune system with production of circulating immune complexes (ICs, one-third of them with cryoprecipitate property. Several factors contribute to the biological activities of ICs, many of which are not completely known. Among them, complement factors play a crucial role in the cold-insoluble ICs-mediated vasculitis, involving primarily small blood vessels in different tissues including skin, kidney, peripheral, and central nervous system. Liver represents the major target of HCV infection with inflammatory infiltrates, resembling secondary lymphoid follicles. Cytokine like CXCL13 contribute to B-cell homing in intraportal lymphoid aggregates, in which B-cell clonal selection may arise. B-cell clonal expansion starts as an antigen-driven event and expands towards indolent and malignant B-cell proliferation. Occurrence of intrahepatic B-cell clonalities correlates with extrahepatic clinical manifestations of HCV infection. In this context, cryoglobulinemic patients should be considered a peculiar HCV-infected population that needs a clinical multidisciplinary approach and more articulated therapeutic measures.

  20. Oral manifestations of hepatitis C virus infection.

    Science.gov (United States)

    Carrozzo, Marco; Scally, Kara

    2014-06-28

    Extrahepatic manifestations (EHMs) of hepatitis C virus (HCV) infection can affect a variety of organ systems with significant morbidity and mortality. Some of the most frequently reported EHM of HCV infection, involve the oral region predominantly or exclusively. Oral lichen planus (OLP) is a chronic inflammatory condition that is potentially malignant and represents cell-mediated reaction to a variety of extrinsic antigens, altered self-antigens, or super antigens. Robust epidemiological evidence support the link between OLP and HCV. As the virus may replicate in the oral mucosa and attract HCV-specific T lymphocytes, HCV may be implicated in OLP pathogenesis. Sjögren syndrome (SjS) is an autoimmune exocrinopathy, characterized by dryness of the mouth and eyes and a multitude of other systemic signs and symptoms. SjS patients have also an increased risk of non-Hodgkin lymphoma. Patients with chronic hepatitis C do frequently have histological signs of Sjögren-like sialadenitis with mild or even absent clinical symptoms. However, it is still unclear if HCV may cause a disease mimicking SjS or it is directly responsible for the development of SjS in a specific subset of patients. Oral squamous cell carcinoma is the most common oral malignant tumour and at least in some part of the world could be linked to HCV.

  1. Simultaneous multiplex PCR detection of seven cucurbit-infecting viruses.

    Science.gov (United States)

    Kwon, Ji Yeon; Hong, Jin Sung; Kim, Min Jea; Choi, Sun Hee; Min, Byeong Eun; Song, Eun Gyeong; Kim, Hyun Hee; Ryu, Ki Hyun

    2014-09-01

    Two multiplex polymerase chain reaction (PCR) systems using dual priming oligonucleotide (DPO) primers were developed for the simultaneous detection of seven cucurbit-infecting viruses. One system allows for the detection of papaya ringspot virus, watermelon mosaic virus, and zucchini yellow mosaic virus, whereas the other permits the detection of cucumber green mottle mosaic virus, cucumber fruit mottle mosaic virus, kyuri green mottle mosaic virus, and zucchini green mottle mosaic virus. Viral species-specific DPO primers developed in this study detected as little as 10 fg/μl of viral RNA under monoplex conditions and 10 pg/μl of viral RNA under multiplex conditions. Multiplex PCR using the DPO primer sets was capable of amplifying viral genes at annealing temperatures ranging from 53 °C to 63 °C. Whereas the use of conventional primers gave rise to non-specific bands, the DPO primers detected target viral genes in the absence of non-specific amplification. When these DPO multiplex primer sets were applied to virus-infected cucurbit samples obtained in the field, multiple infection as well as single infection was accurately identified. This novel approach could also detect multiple viruses in infected seeds. The reliability of multiplex PCR systems using DPO primers for plant virus detection is discussed.

  2. Transmission potential of Zika virus infection in the South Pacific

    Directory of Open Access Journals (Sweden)

    Hiroshi Nishiura

    2016-04-01

    Conclusions: The transmissibility of Zika virus infection appears to be comparable to those of dengue and chikungunya viruses. Considering that Aedes species are a shared vector, this finding indicates that Zika virus replication within the vector is perhaps comparable to dengue and chikungunya.

  3. Immune Activation in the Pathogenesis of Dengue Virus Infection

    NARCIS (Netherlands)

    C.A.M. van de Weg (Cornelia A.M.)

    2014-01-01

    markdownabstract__Abstract__ Dengue virus (DENV) is a positive-stranded RNA virus and belongs to the Flaviviridae family. The virus is transmitted by the bite of an infected Aedes-mosquito and circulates in tropical and subtropical areas around the world. The incidence of dengue has risen dramatica

  4. Postmortem Investigations Following Human Immunodeficiency Virus Infection

    Directory of Open Access Journals (Sweden)

    Andrey V. Bychkov

    2009-04-01

    of leukemia and one case of cervical cancer. Conclusions: Tuberculosis was the most widespread among the opportunistic infections, which often had affected the entire lung and had a destructive form. In the morphological picture of tuberculous inflammation, alterative and exudative changes dominated. Moreover, HIV infection had a characteristically broad spectrum of causative agents of pneumonia, including bacteria, viruses, fungi, and protozoa.

  5. First Imported Case of Zika Virus Infection into Korea.

    Science.gov (United States)

    Jang, Hee-Chang; Park, Wan Beom; Kim, Uh Jin; Chun, June Young; Choi, Su-Jin; Choe, Pyoeng Gyun; Jung, Sook-In; Jee, Youngmee; Kim, Nam-Joong; Choi, Eun Hwa; Oh, Myoung-Don

    2016-07-01

    Since Zika virus has been spreading rapidly in the Americas from 2015, the outbreak of Zika virus infection becomes a global health emergency because it can cause neurological complications and adverse fetal outcome including microcephaly. Here, we report clinical manifestations and virus isolation findings from a case of Zika virus infection imported from Brazil. The patient, 43-year-old Korean man, developed fever, myalgia, eyeball pain, and maculopapular rash, but not neurological manifestations. Zika virus was isolated from his semen, and reverse-transcriptase PCR was positive for the virus in the blood, urine, and saliva on the 7th day of the illness but was negative on the 21st day. He recovered spontaneously without any neurological complications. He is the first case of Zika virus infection in Korea imported from Brazil.

  6. Negative-strand RNA viruses: The plant-infecting counterparts

    NARCIS (Netherlands)

    Kormelink, R.J.M.; Garcia, M.L.; Goodin, M.; Sasaya, T.; Haenni, A.L.

    2011-01-01

    While a large number of negative-strand (-)RNA viruses infect animals and humans, a relative small number have plants as their primary host. Some of these have been classified within families together with animal/human infecting viruses due to similarities in particle morphology and genome organizat

  7. Mayaro Virus Infection, Amazon Basin Region, Peru, 2010–2013

    OpenAIRE

    Halsey, Eric S; Siles, Crystyan; Guevara, Carolina; Vilcarromero, Stalin; Erik J. Jhonston; Ramal, Cesar; Aguilar, Patricia V.; Ampuero, Julia S.

    2013-01-01

    During 2010–2013, we recruited 16 persons with confirmed Mayaro virus infection in the Peruvian Amazon to prospectively follow clinical symptoms and serologic response over a 12-month period. Mayaro virus infection caused long-term arthralgia in more than half, similar to reports of other arthritogenic alphaviruses.

  8. Mayaro virus infection, Amazon Basin region, Peru, 2010-2013.

    Science.gov (United States)

    Halsey, Eric S; Siles, Crystyan; Guevara, Carolina; Vilcarromero, Stalin; Jhonston, Erik J; Ramal, Cesar; Aguilar, Patricia V; Ampuero, Julia S

    2013-11-01

    During 2010-2013, we recruited 16 persons with confirmed Mayaro virus infection in the Peruvian Amazon to prospectively follow clinical symptoms and serologic response over a 12-month period. Mayaro virus infection caused long-term arthralgia in more than half, similar to reports of other arthritogenic alphaviruses.

  9. Zika virus infection acquired during brief travel to Indonesia.

    Science.gov (United States)

    Kwong, Jason C; Druce, Julian D; Leder, Karin

    2013-09-01

    Zika virus infection closely resembles dengue fever. It is possible that many cases are misdiagnosed or missed. We report a case of Zika virus infection in an Australian traveler who returned from Indonesia with fever and rash. Further case identification is required to determine the evolving epidemiology of this disease.

  10. Phyllanthus species for chronic hepatitis B virus infection

    DEFF Research Database (Denmark)

    Yun, Xia; Luo, Hui; Liu, Jian Ping

    2011-01-01

    Phyllanthus species for patients with chronic hepatitis B virus (HBV) infection have been assessed in clinical trials, but no consensus regarding their usefulness exists.......Phyllanthus species for patients with chronic hepatitis B virus (HBV) infection have been assessed in clinical trials, but no consensus regarding their usefulness exists....

  11. Susceptibility of different leukocyte cell types to Vaccinia virus infection

    Directory of Open Access Journals (Sweden)

    Sánchez-Puig Juana M

    2004-11-01

    Full Text Available Abstract Background Vaccinia virus, the prototype member of the family Poxviridae, was used extensively in the past as the Smallpox vaccine, and is currently considered as a candidate vector for new recombinant vaccines. Vaccinia virus has a wide host range, and is known to infect cultures of a variety of cell lines of mammalian origin. However, little is known about the virus tropism in human leukocyte populations. We report here that various cell types within leukocyte populations have widely different susceptibility to infection with vaccinia virus. Results We have investigated the ability of vaccinia virus to infect human PBLs by using virus recombinants expressing green fluorescent protein (GFP, and monoclonal antibodies specific for PBL subpopulations. Flow cytometry allowed the identification of infected cells within the PBL mixture 1–5 hours after infection. Antibody labeling revealed that different cell populations had very different infection rates. Monocytes showed the highest percentage of infected cells, followed by B lymphocytes and NK cells. In contrast to those cell types, the rate of infection of T lymphocytes was low. Comparison of vaccinia virus strains WR and MVA showed that both strains infected efficiently the monocyte population, although producing different expression levels. Our results suggest that MVA was less efficient than WR in infecting NK cells and B lymphocytes. Overall, both WR and MVA consistently showed a strong preference for the infection of non-T cells. Conclusions When infecting fresh human PBL preparations, vaccinia virus showed a strong bias towards the infection of monocytes, followed by B lymphocytes and NK cells. In contrast, very poor infection of T lymphocytes was detected. These finding may have important implications both in our understanding of poxvirus pathogenesis and in the development of improved smallpox vaccines.

  12. Immunomodulatory Activity of Red Ginseng against Influenza A Virus Infection

    Directory of Open Access Journals (Sweden)

    Jong Seok Lee

    2014-01-01

    Full Text Available Ginseng herbal medicine has been known to have beneficial effects on improving human health. We investigated whether red ginseng extract (RGE has preventive effects on influenza A virus infection in vivo and in vitro. RGE was found to improve survival of human lung epithelial cells upon influenza virus infection. Also, RGE treatment reduced the expression of pro-inflammatory genes (IL-6, IL-8 probably in part through interference with the formation of reactive oxygen species by influenza A virus infection. Long-term oral administration of mice with RGE showed multiple immunomodulatory effects such as stimulating antiviral cytokine IFN-γ production after influenza A virus infection. In addition, RGE administration in mice inhibited the infiltration of inflammatory cells into the bronchial lumens. Therefore, RGE might have the potential beneficial effects on preventing influenza A virus infections via its multiple immunomodulatory functions.

  13. Absence of human metapneumovirus co-infection in cases of severe respiratory syncytial virus infection

    NARCIS (Netherlands)

    van Woensel, J B M; Bos, A P; Lutter, R; Rossen, J W A; Schuurman, R

    2006-01-01

    It has been suggested that co-infection of human metapneumovirus (hMPV) in severe respiratory syncytial (RSV) virus bronchiolitis is very common. To evaluate the epidemiology of hMPV co-infection in children with severe lower respiratory tract infection caused by RSV virus. This was an observational

  14. Bovine respiratory disease model based on dual infections with infection with bovine viral diarrhea virus and bovine corona virus

    Science.gov (United States)

    Bovine respiratory disease complex (BRDC) is the leading cause of economic loss in the U.S. cattle industry. BRDC likely results from simultaneous or sequential infections with multiple pathogens including both viruses and bacteria. Bovine viral diarrhea virus (BVDV) and bovine corona virus (BoCV...

  15. Targeting of non-dominant antigens as a vaccine strategy to broaden T-cell responses during chronic viral infection

    DEFF Research Database (Denmark)

    Holst, Peter Johannes; Jensen, Benjamin Anderschou Holbech; Ragonnaud, Emeline

    2015-01-01

    In this study, we compared adenoviral vaccine vectors with the capacity to induce equally potent immune responses against non-dominant and immunodominant epitopes of murine lymphocytic choriomeningitis virus (LCMV). Our results demonstrate that vaccination targeting non-dominant epitopes facilita......In this study, we compared adenoviral vaccine vectors with the capacity to induce equally potent immune responses against non-dominant and immunodominant epitopes of murine lymphocytic choriomeningitis virus (LCMV). Our results demonstrate that vaccination targeting non-dominant epitopes...... by vaccination. In addition, our findings suggest that prior adenoviral vaccination is not likely to negatively impact the long-term and protective immune response induced and maintained by a vaccine-attenuated chronic viral infection....

  16. Prevalence of occult hepatitis C virus infection in the Iranian patients with human immunodeficiency virus infection.

    Science.gov (United States)

    Bokharaei-Salim, Farah; Keyvani, Hossein; Esghaei, Maryam; Zare-Karizi, Shohreh; Dermenaki-Farahani, Sahar-Sadat; Hesami-Zadeh, Khashayar; Fakhim, Shahin

    2016-11-01

    Occult hepatitis C virus (HCV) infection is a new form of chronic HCV infection described by the presence of the genomic HCV-RNA in liver biopsy and/or peripheral blood mononuclear cell (PBMC) samples, and undetectable levels or absence of HCV-RNA and in the absence or presence of anti HCV antibodies in the plasma specimens. The aim of the present study was to evaluate the occurrence of occult HCV infection (OCI) among Iranian subjects infected with human immunodeficiency virus (HIV) using RT-nested PCR. From March 2014 until April 2015, 109 Iranian patients with established HIV infection were enrolled in this cross-sectional study. After extraction of viral RNA from the plasma and PBMC samples, HCV-RNA status was examined by RT-nested PCR using primers from the 5'-NTR. HCV genotyping was conducted using RFLP analysis. For the confirmation of HCV genotyping by RFLP method, the PCR products were sequenced. Of the 109 patients, 50 were positive for antibodies against HCV. The HCV-RNA was detected in PBMC specimens in 6 (10.2%) out of the total 59 patients negative for anti-HCV Abs and undetectable plasma HCV-RNA and also from 4 (8.0%) out of the total 50 patients positive for anti-HCV Abs and undetectable plasma HCV-RNA. HCV genotyping analysis showed that 6 (60.0%) patients were infected with HCV subtype 3a, 3 (30.0%) were infected with HCV subtype 1a and 1 (10.0%) patient was infected with HCV subtype 1b. This study revealed the incidence of OCI (9.2%) in HIV-infected Iranian patients. Hence, designing prospective studies focusing on the detection of OCI in these patients would provide more information. J. Med. Virol. 88:1960-1966, 2016. © 2016 Wiley Periodicals, Inc.

  17. Plant RNA binding proteins for control of RNA virus infection

    OpenAIRE

    Huh, Sung Un; Paek, Kyung-Hee

    2013-01-01

    Plant RNA viruses have effective strategies to infect host plants through either direct or indirect interactions with various host proteins, thus suppressing the host immune system. When plant RNA viruses enter host cells exposed RNAs of viruses are recognized by the host immune system through processes such as siRNA-dependent silencing. Interestingly, some host RNA binding proteins have been involved in the inhibition of RNA virus replication, movement, and translation through RNA-specific b...

  18. ELECTRON MICROSCOPE EVIDENCE OF VIRUS INFECTION IN CULTURED MARINE FISH

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Electron microscope investigation on the red sea bream (Pagrosomus major), bastard halibut (Paralichthys olivaceus) and stone flounder (Kareius bicoloratus) in North China revealed virus infection in the bodies of the dead and diseased fish. These viruses included the lymphocystis disease virus (LDV), parvovirus, globular virus, and a kind of baculavirus which was not discovered and reported before and is now tentatively named baculavirus of stone flounder (Kareius bicoloratus).

  19. Zika virus infections imported from Brazil to Portugal, 2015

    OpenAIRE

    L. Zé-Zé; M.B. Prata; Teixeira, T; Marques, N.; Mondragão, A.; Fernandes, R; Saraiva da Cunha, J.; Alves, M. J.

    2016-01-01

    Zika virus is an emerging arbovirus transmitted by Aedes sp. mosquitoes like the Dengue and Chikungunya viruses. Zika virus was until recently considered a mild pathogenic mosquito-borne flavivirus with very few reported benign human infections. In 2007, an epidemic in Micronesia initiated the turnover in the epidemiological history of Zika virus and more recently, the potential association with congenital microcephaly cases in Brazil 2015, still under investigation, led the World Health Orga...

  20. Facilitative and antagonistic interactions between plant viruses in mixed infections.

    Science.gov (United States)

    Syller, Jerzy

    2012-02-01

    Mixed infections of plant viruses are common in nature, and a number of important virus diseases of plants are the outcomes of interactions between causative agents. Multiple infections lead to a variety of intrahost virus-virus interactions, many of which may result in the generation of variants showing novel genetic features, and thus change the genetic structure of the viral population. Hence, virus-virus interactions in plants may be of crucial significance for the understanding of viral pathogenesis and evolution, and consequently for the development of efficient and stable control strategies. The interactions between plant viruses in mixed infections are generally categorized as synergistic or antagonistic. Moreover, mixtures of synergistic and antagonistic interactions, creating usually unpredictable biological and epidemiological consequences, are likely to occur in plants. The mechanisms of some of these are still unknown. This review aims to bring together the current knowledge on the most commonly occurring facilitative and antagonistic interactions between related or unrelated viruses infecting the same host plant. The best characterized implications of these interactions for virus-vector-host relationships are included. The terms 'synergism' and 'helper dependence' for facilitative virus-virus interactions, and 'cross-protection' and 'mutual exclusion' for antagonistic interactions, are applied in this article.

  1. Hepatitis B virus infection in children.

    LENUS (Irish Health Repository)

    O'Gorman, C S

    2012-02-01

    Recent increases in Hepatitis B virus (HBV) infection prompted us to characterize HBV-infected children in Ireland and to audit management, by reviewing prospectively gathered data. Of 46 children (29 [63%] male), median age at presentation was 8.1 years (range 0.6-17.6), monitoring duration was 22.5 months (range 1-101), 23\\/46 (50%) were European (including 9 [19.6%] Irish), 15 (32.6%) African and 9 (19.6%) Asian. Acquisition was vertical (25\\/46 [54.3%]), horizontal (5\\/46 [10.9%]), unknown (16\\/46 [34.8%]). HBV-DNA was >100,000,000 cpm in 20\\/32 (62.5%) with chronic infection. Hepatitis B e antigen (HBeAg) was detected in 32\\/44 (72.7%). We estimate that universal neonatal vaccination (UNV-HBV) could have prevented 22% of cases, and could limit further horizontal HBV spread. This supports the recent introduction of UNV-HBV.

  2. Limiting influenza virus, HIV and dengue virus infection by targeting viral proteostasis

    Science.gov (United States)

    Heaton, Nicholas S.; Moshkina, Natasha; Fenouil, Romain; Gardner, Thomas J.; Aguirre, Sebastian; Shah, Priya S.; Zhao, Nan; Manganaro, Lara; Hultquist, Judd; Noel, Justine; Sachs, David; Hamilton, Jennifer; Leon, Paul E.; Chawdury, Amit; Tripathy, Shashank; Melegari, Camilla; Campisi, Laura; Hai, Rong; Metreveli, Giorgi; Gamarnik, Andrea V.; García-Sastre, Adolfo; Greenbaum, Benjamin; Simon, Viviana; Fernandez-Sesma, Ana; Krogan, Nevan; Mulder, Lubbertus C.F.; van Bakel, Harm; Tortorella, Domenico; Taunton, Jack; Palese, Peter; Marazzi, Ivan

    2016-01-01

    Viruses are obligate parasites as they require the machinery of the host cell to replicate. Inhibition of host factors co-opted during active infection is a strategy to suppress viral replication and a potential pan antiviral therapy. To define the cellular proteins and processes required for a virus during infection is thus crucial to understanding the mechanisms of virally induced disease. In this report, we generated fully infectious tagged influenza viruses and used infection-based proteomics to identify pivotal arms of cellular signaling required for influenza virus growth and infectivity. Using mathematical modeling, genetic, and pharmacologic approaches, we revealed that modulation of Sec61-mediated cotranslational translocation selectively impaired glycoprotein proteostasis of influenza as well as HIV and dengue viruses, and led to inhibition of viral growth and infectivity. Thus, by studying virus-human protein-protein interactions in the context of active replication we have identified targetable host factors for broad-spectrum antiviral therapies. PMID:26789921

  3. Occult hepatitis B virus infection in Egypt

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    The emerging evidence of the potentially clinicalimportance of occult hepatitis B virus (HBV) infection(OBI) increases the interest in this topic. OBI mayimpact in several clinical contexts, which include thepossible transmission of the infection, the contributionto liver disease progression, the development ofhepatocellular carcinoma, and the risk of reactivation.There are several articles that have published on OBI inEgyptian populations. A review of MEDLINE databasewas undertaken for relevant articles to clarify theepidemiology of OBI in Egypt. HBV genotype D is theonly detectable genotype among Egyptian OBI patients.Higher rates of OBI reported among Egyptian chronicHCV, hemodialysis, children with malignant disorders, andcryptogenic liver disease patients. There is an evidenceof OBI reactivation after treatment with chemotherapy.The available data suggested that screening for OBI mustbe a routine practice in these groups of patients. Furtherstudies needed for better understand of the epidemiologyof OBI among Egyptian young generations after the eraof hepatitis B vaccination.

  4. Unfolded protein response in hepatitis C virus infection

    Directory of Open Access Journals (Sweden)

    Shiu-Wan eChan

    2014-05-01

    Full Text Available Hepatitis C virus (HCV is a single-stranded, positive-sense RNA virus of clinical importance. The virus establishes a chronic infection and can progress from chronic hepatitis, steatosis to fibrosis, cirrhosis and hepatocellular carcinoma. The mechanisms of viral persistence and pathogenesis are poorly understood. Recently the unfolded protein response (UPR, a cellular homeostatic response to endoplasmic reticulum (ER stress, has emerged to be a major contributing factor in many human diseases. It is also evident that viruses interact with the host UPR in many different ways and the outcome could be pro-viral, anti-viral or pathogenic, depending on the particular type of infection. Here we present evidence for the elicitation of chronic ER stress in HCV infection. We analyze the UPR signaling pathways involved in HCV infection, the various levels of UPR regulation by different viral proteins and finally, we propose several mechanisms by which the virus provokes the UPR.

  5. [Latent infection of human herpes virus in hematopoietic system].

    Science.gov (United States)

    Wu, Ke-Fu; Ma, Xiao-Tong; Zheng, Guo-Guang; Song, Yu-Hua

    2008-12-01

    Up to date, eight types of human herpes viruses have been identified, all of which are ubiquitous, and usually establish latent infection in the host after primary infection. Since most of the herpes viruses are maintained in an asymptomatic form, they are often neglected. However, under some circumstances, these herpes viruses can cause fatal or severe diseases. Furthermore, the association of herpes viruses with hematopoietic malignancies is attracting researchers' attention. With the extensive development of hematopoietic stem cell and organ transplantation, reports regarding transplantation failure and complication caused by infection of human herpes virus has been increasing. Cytokine storm was firstly suggested as the mechanism of graft-versus-host diseases. In recent years, which has also been applied in the pathogenesis research of inflammation, and is supposed to play an important role in severe virus infection. In this paper, through discussing the possible role of latent infection of human herpes virus in the failure or complication of bone marrow or hematopoietic stem cell transplantation, and in refractory leukemia, the function and significance of latent infection of human herpes virus and the cytokine storm it caused were investigated.

  6. Antibody dependent enhancement of frog virus 3 infection

    Directory of Open Access Journals (Sweden)

    Penny Emily

    2010-02-01

    Full Text Available Abstract Background Viruses included in the family Iridoviridae are large, icosahedral, dsDNA viruses that are subdivided into 5 genera. Frog virus 3 (FV3 is the type species of the genus Ranavirus and the best studied iridovirus at the molecular level. Typically, antibodies directed against a virus act to neutralize the virus and limit infection. Antibody dependent enhancement occurs when viral antibodies enhance infectivity of the virus rather than neutralize it. Results Here we show that anti-FV3 serum present at the time of FV3 infection enhances infectivity of the virus in two non-immune teleost cell lines. We found that antibody dependent enhancement of FV3 was dependent on the Fc portion of anti-FV3 antibodies but not related to complement. Furthermore, the presence of anti-FV3 serum during an FV3 infection in a non-immune mammalian cell line resulted in neutralization of the virus. Our results suggest that a cell surface receptor specific to teleost cell lines is responsible for the enhancement. Conclusions This report represents the first evidence of antibody dependent enhancement in iridoviruses. The data suggests that anti-FV3 serum can either neutralize or enhance viral infection and that enhancement is related to a novel antibody dependent enhancement pathway found in teleosts that is Fc dependent.

  7. Naturally occurring Parelaphostrongylus tenuis-associated choriomeningitis in a guinea pig with neurologic signs.

    Science.gov (United States)

    Southard, T; Bender, H; Wade, S E; Grunenwald, C; Gerhold, R W

    2013-05-01

    An adult male guinea pig (Cavia porcellus) with a 1-month history of hind limb paresis, torticollis, and seizures was euthanized and submitted for necropsy. Gross examination was unremarkable, but histologic examination revealed multifocal eosinophilic and lymphoplasmacytic choriomeningitis and cross sections of nematode parasites within the leptomeninges of the midbrain and diencephalon. Morphologic features of the nematode were consistent with a metastrongyle, and the parasite was identified as Parelaphostrongylus tenuis by polymerase chain reaction testing and nucleotide sequencing. Further questioning of the owner revealed that the guinea pig was fed grass from a yard often grazed by white-tailed deer (Odocoileus virginianus). To the authors' knowledge, this is the first report of a naturally occurring P. tenuis infection in a guinea pig.

  8. Occult hepatitis B virus infection in Egyptian hemodialysis patients with or without hepatitis C virus infection

    Directory of Open Access Journals (Sweden)

    Hisham Ismail

    2010-08-01

    Full Text Available Hisham Ismail1*, Mohamed Soliman2, Nahed Ismail31Department of Molecular Diagnosis, GEBR Institute, 2Department of Clinical Pathology, College of Medicine, Menoufia University, Menoufia, Egypt; 3Department of Pathology and Department of Microbiology and Immunology, Meharry Medical College, Nashville, Tennessee, USA *Current affiliation: College of Medicine, Qassim University, Saudi ArabiaAbstract: Hepatitis B virus (HBV and hepatitis C virus (HCV infections are frequent in patients with end-stage renal disease who are on maintenance hemodialysis. There are limited data about the prevalence of occult HBV infection in patients on long-term hemodialysis. Occult HBV is defined as positive HBV DNA in the blood in the absence of hepatitis B surface ­antigen in the serum. In this study, we determined the prevalence of occult HBV in hemodialysis patients with or without HCV infection. The study included 116 patients with end-stage renal disease on chronic hemodialysis, of whom 64 patients were HCV RNA positive (Group 1, and 52 were HCV RNA negative (Group 2. We found that four of 64 (6.3% hemodialysis patients with HCV infection (Group 1 had occult HBV, while only two of 52 (3.8% hemodialysis patients without HCV (Group 2 had occult HBV. We then examined whether gender-matched ­hemodialysis patients with positive HBV DNA in the two hemodialysis groups differed in specific parameters, ie, age, degree of liver dysfunction, and presence of ­coinfection with schistosomiasis, a common parasitic infection of the liver. We found no significant difference between the groups having positive HBV DNA with regard to serum levels of liver enzymes, aspartate transaminase, albumin, and hepatitis B core antigen (P > 0.05. However, we detected significantly higher levels of alanine transaminase, a prolonged duration of hemodialysis, and higher levels of schistosomal antibodies in Group 1 than in Group 2. Interestingly, we found that the presence of schistosomal

  9. Detection of transient and persistent feline leukaemia virus infections.

    Science.gov (United States)

    Jarrett, O; Golder, M C; Stewart, M F

    1982-03-01

    A study was made of cats persistently or transiently viraemic with feline leukaemia virus (FeLV) following experimental oronasal infection. Cats of two ages were exposed to the virus. One group was infected when eight weeks old in the expectation that most of the cats would become persistently viraemic, and the second group when 16 weeks old, so that some would show signs of a transient infection and then recover. The periods following infection when virus was detectable in the blood and in the oropharynx were determined for each group. Three methods for detecting viraemia were compared: virus isolation, immunofluorescence on blood smears and an enzyme-linked immunosorbent assay (ELISA). There was good overall agreement among the three tests in detecting virus-positive cats. Virus was found sooner after infection by virus isolation than by the other methods, and virus appeared in the blood slightly sooner in cats which developed persistent viraemia than in transiently viraemic cats. Infectious FeLV was isolated from the oropharynx of all of the persistently viraemic cats, in most cases simultaneously with virus in the plasma. Virus was also isolated from the mouth of most transiently viraemic cats. Under field conditions such transient excretion of virus lasting only a few days would rarely be detected in a single sampling. This might explain how FeLV is maintained in free range urban cats in the absence of a large number of cats with persistent active FeLV infection. For routine diagnosis, immunofluorescence would appear to offer the best chance of differentiating transient and persistent infections by FeLV.

  10. Innate immune responses in hepatitis B virus (HBV) infection

    OpenAIRE

    Busca, Aurelia; Kumar, Ashok

    2014-01-01

    Hepatitis B virus (HBV) infection has a low rate of chronicity compared to HCV infection, but chronic liver inflammation can evolve to life threatening complications. Experimental data from HBV infected chimpanzees and HBV transgenic mice have indicated that cytotoxic T cells are the main cell type responsible for inhibition of viral replication, but also for hepatocyte lysis during chronic HBV infection. Their lower activation and impaired function in later stages of infection was suggested ...

  11. Sensitization to lipopolysaccharide in mice with asymptomatic viral infection: role of T cell-dependent production of interferon-gamma

    DEFF Research Database (Denmark)

    Nansen, A; Christensen, Jan Pravsgaard; Marker, O

    1997-01-01

    The interplay between viral infection and lipopolysaccharide (LPS) was studied. Infection with a noncytopathogenic virus, lymphocytic choriomeningitis virus (LCMV), was found to sensitize mice to low doses of LPS. In vivo, this hypersensitivity correlated with hyperproduction of tumor necrosis...... was observed in LCMV-infected, T cell-deficient mice and in mice infected with vesicular stomatitis virus, a virus that induces much less T cell activation than does LCMV. Finally, LCMV infection was much less efficient in priming IFN-gamma knockout mice for hyperproduction of TNF-alpha. These findings...... indicate that clinically silent viral infections may induce hypersensitivity to LPS through T cell activation and subsequent production of IFN-gamma; this sensitizes monocytes/macrophages for hyperproduction of TNF-alpha....

  12. Occult hepatitis B virus infection in Moroccan HIV infected patients

    Directory of Open Access Journals (Sweden)

    Tahar Bajjou

    2015-03-01

    Full Text Available Background: The purpose of this study is to assess the prevalence of Occult hepatitis B virus Infection (OBI among antiretroviral treatment na and iuml;ve HIV-1 infected individuals in Morocco and to determine factors favouring its occurrence. Methods: The retrospective study was conducted in the Mohammed V military teaching hospital in Rabat between January 2010 and June 2011. It included patients with confirmed HIV infection, tested negative to serological detection of HBV surface antigen (HBsAg and did not received antiviral treatment or hepatitis B vaccine. All samples were tested for anti-HBc, anti-HBs and anti-HCV antibodies using enzyme immunoassay (ELISA. The detection of HBV DNA was performed by real-time PCR using two specific primers for a gene in the region C of the viral genome. The sensitivity of the technique was 20 copies/ml. Results: A total of 82 samples were analyzed, 19 (23 % were found to have isolated anti-HBc, 07 (8.5% with associated anti-HBc and Anti-HBs. No anti-HCV marker was detected on these screening samples. The HBV DNA was detected in 48 (58% samples, of which, males constituted 58% (28/48. The mean age of these patients was 38 +/- 8.2 (29-56, the median HIV-1 viral load and CD4 cell count HIV-1 infected patients were 127500 (54108-325325 copies/ml and 243 [80-385] cells/mm3 respectively and 27.1% (13/48 of these patients were found to have isolated anti-HBc. A significant correlations between DNA HBV and HIV viral load higher than 100000 copies/ml (P = 0.004, CD4 cell count lower than 400 cells/mm3 (P = 0.013, P = 0.006 and isolated anti-HBc samples (P <0.005 were founded. However there was no significant association with age, sex, transmission mode and clinical stage. Conclusion: The consequences of this high prevalence of OBI in Morocco need to be considered in laboratory diagnosis of HBV infection in HIV infected patients and the PCR seems to be inevitable for a better diagnosis and therapy. [Int J Res Med Sci

  13. Ozone response of tomato plants infected with cucumber mosaic virus and/or tobacco mosaic virus

    Energy Technology Data Exchange (ETDEWEB)

    Ormrod, D.P.; Kemp, W.G.

    1979-10-01

    The sensitivity of three tomato cultivars to several concentrations of ozone was evaluated after prior sequential inoculations with tobacco mosaic virus (TMV) and/or cucumber mosaic virus (CMV). Ozone injury in inoculated and uninoculated tomatoes varied from slight to severe depending on the virus, cultivar, ozone concentration and virus incubation period. The frequency of increased ozone injury was about twice as great as that of suppressed injury on infected plants. Ozone injury occurred more frequently in TMV-inoculated plants than in those inoculated with CMV. There were more increases than decreases in ozone injury after 7 or 14 days of virus infection, but mainly decreases in injury after 21 days infection. Growth was significantly reduced in plants exposed to ozone after a 21-day virus incubation period, particularly when they were inoculated with both viruses.

  14. Virus-induced secondary bacterial infection: a concise review

    Science.gov (United States)

    Hendaus, Mohamed A; Jomha, Fatima A; Alhammadi, Ahmed H

    2015-01-01

    Respiratory diseases are a very common source of morbidity and mortality among children. Health care providers often face a dilemma when encountering a febrile infant or child with respiratory tract infection. The reason expressed by many clinicians is the trouble to confirm whether the fever is caused by a virus or a bacterium. The aim of this review is to update the current evidence on the virus-induced bacterial infection. We present several clinical as well in vitro studies that support the correlation between virus and secondary bacterial infections. In addition, we discuss the pathophysiology and prevention modes of the virus–bacterium coexistence. A search of the PubMed and MEDLINE databases was carried out for published articles covering bacterial infections associated with respiratory viruses. This review should provide clinicians with a comprehensive idea of the range of bacterial and viral coinfections or secondary infections that could present with viral respiratory illness. PMID:26345407

  15. Occult hepatitis C virus infection is more common than hepatitis B infection in maintenance hemodialysis patients

    OpenAIRE

    Jain, Pankaj; Nijhawan, Sandeep

    2008-01-01

    Patients of end stage renal disease on maintenance hemodialysis were enrolled to study the prevalence of occult and dual hepatitis B virus (HBV) and hepatitis C virus (HCV) infection and non-occult hepatitis B and C virus infection. One hundred and two patients were enrolled. Thirty patients had HCV infection, three of them were positive in anti-HCV. So, 27 (90%) of HCV-positive patients had occult HCV infection. Eleven (11%) patients had HBV infection. Five patients were positive in anti-HBc...

  16. Infectivity of blood products from donors with occult hepatitis B virus infection

    DEFF Research Database (Denmark)

    Allain, Jean-Pierre; Mihaljevic, Ivanka; Gonzalez-Fraile, Maria Isabel

    2013-01-01

    Occult hepatitis B virus (HBV) infection (OBI) is identified in 1:1000 to 1:50,000 European blood donations. This study intended to determine the infectivity of blood products from OBI donors.......Occult hepatitis B virus (HBV) infection (OBI) is identified in 1:1000 to 1:50,000 European blood donations. This study intended to determine the infectivity of blood products from OBI donors....

  17. Cucumber Mosaic Virus and Chili Veinal Mottle Virus Infection on Growth and Yield Component of Chilli

    Directory of Open Access Journals (Sweden)

    ENDANG NURHAYATI

    2006-06-01

    Full Text Available A research was undergone to study the effect of single and double infection of Cucumber Mosaic Virus (CMV and Chili Veinal Mottle Virus (ChiVMV on the growth and yield of five chilli cultivars, i.e. Prabu, Taro, Jatilaba, Laris, and Keriting Bogor. Mechanical inoculation was conducted to transmit the virus. Infection of the virus was then confirmed with DAS-ELISA. Severe symptom was observed on plant given double infection compared to those given single infection. The rate of plant growth and the amount and weight of fruits were reduced. The type of interaction between CMV and ChiVMV on most chilli cultivar can be considered as interference and additive. Synergism interaction was only observed on cultivar Laris. Based on symptom expression and reduction on yield, it can be concluded that all chilli cultivars used in this study could not hold up the virus infection.

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

    Directory of Open Access Journals (Sweden)

    Müller Marcel A

    2005-02-01

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

  19. 21 CFR 866.3360 - Lymphocytic choriomeningitis virus serological reagents.

    Science.gov (United States)

    2010-04-01

    ... cerebral meningitis (inflammation of membranes that envelop the brain) and occasionally a mild pneumonia... meningitis and pneumonia. (b) Classification. Class I (general controls). The device is exempt from...

  20. Prevalence of Hepatitis Virus Infections in an Institution for Persons with Developmental Disabilities.

    Science.gov (United States)

    Woodruff, Bradley A.; Vazquez, Elizabeth

    2002-01-01

    A study involving 1,235 residents of Sonoma Developmental Center found 3 residents had hepatitis C virus infections, and 633 had past or current hepatitis B virus infections. The prevalence of hepatitis B virus infection rose rapidly with longer residence in institutions. Hepatitis A virus infection had occurred in 494 residents. (Contains…

  1. The pathogenesis of Epstein-Barr virus persistent infection.

    Science.gov (United States)

    Thorley-Lawson, David A; Hawkins, Jared B; Tracy, Sean I; Shapiro, Michael

    2013-06-01

    Epstein-Barr virus (EBV) maintains a lifelong infection. According to the germinal center model (GCM), latently infected B cells transit the germinal center (GC) to become resting memory cells. Here, the virus resides quiescently, occasionally reactivating to infect new B cells, completing the cycle of infection. The GCM remains the only model that explains EBV biology and the pathogenesis of lymphoma. Recent work suggests modifications to the model notably that the virus contributes only modestly to the GC process and predictions from mathematical models that quiescence within memory B cells shapes the overall structure of viral infection but is not essential for persistence. Rather, it is the cycle of infection which allows viral persistence at the very low levels observed.

  2. Zika virus productively infects primary human placenta-specific macrophages

    Science.gov (United States)

    Jurado, Kellie Ann; Simoni, Michael K.; Tang, Zhonghua; Uraki, Ryuta; Hwang, Jesse; Householder, Sarah; Wu, Mingjie; Lindenbach, Brett D.; Abrahams, Vikki M.; Guller, Seth

    2016-01-01

    The strong association of Zika virus infection with congenital defects has led to questions of how a flavivirus is capable of crossing the placental barrier to reach the fetal brain. Here, we demonstrate permissive Zika virus infection of primary human placental macrophages, commonly referred to as Hofbauer cells, and placental villous fibroblasts. We also demonstrate Zika virus infection of Hofbauer cells within the context of the tissue ex vivo using term placental villous explants. In addition to amplifying infectious virus within a usually inaccessible area, the putative migratory activities of Hofbauer cells may aid in dissemination of Zika virus to the fetal brain. Understanding the susceptibility of placenta-specific cell types will aid future work around and understanding of Zika virus–associated pregnancy complications. PMID:27595140

  3. Fibromyalgia-associated hepatitis C virus infection.

    Science.gov (United States)

    Rivera, J; de Diego, A; Trinchet, M; García Monforte, A

    1997-09-01

    The objective was to determine whether there might be an association between hepatitis C virus (HCV) chronic infection and fibromyalgia (FM). We determined the prevalence of HCV infection in 112 FM patients, in comparison with matched rheumatoid arthritis (RA) patients from the out-patient clinic of a teaching tertiary care general hospital. Furthermore, we looked for evidence of FM in 58 patients diagnosed with chronic hepatitis due to HCV, compared with matched surgery clinic patients, HCV antibodies were determined by enzyme-linked immunosorbent assay (ELISA) and recombinant immunoblot assay (RIBA). Serum RNA of HCV (HCV-RNA) was determined by polymerase chain reaction. In the group of FM patients, HCV antibodies were found by ELISA in 17 (15.2%) patients and in six (5.3%) of the RA controls (P < 0.05). RIBA was positive in 16 and indeterminate in one of the FM patients. Serum HCV-RNA was found in 13 of these FM patients. In eight (47%) FM patients, alanine aminotransferase (ALT) was normal, although HCV-RNA was detected in four (50%) of them. In the group of patients with chronic hepatitis due to HCV, all patients had HCV antibodies and the presence of HCV-RNA in serum. Within these patients, 31 (53%) had diffuse musculoskeletal pain, while six (10%) fulfilled FM diagnostic criteria. In the control group, 13/58 (22%) had diffuse musculoskeletal pain (P < 0.001), whereas only one female patient (1.7%) fulfilled FM criteria (P < 0.05). Serum ALT was 51.7 +/- 38.4 in FM patients, whereas it was 122 +/- 76.3 in patients with HCV chronic hepatitis but without FM (P < 0.001). There were no statistical differences in autoimmune markers between patients with and without FM. These data suggest that there exists an association between FM and active HCV infection in some of our patients. FM is not associated with liver damage or autoimmune markers in these patients. HCV infection should be considered in FM patients even though ALT elevations were absent.

  4. Cardiovascular implications from untreated human immunodeficiency virus infection

    DEFF Research Database (Denmark)

    Baker, Jason V; Lundgren, Jens D

    2011-01-01

    Atherosclerotic cardiovascular disease (CVD) has become an important cause of morbidity and mortality among individuals with human immunodeficiency virus (HIV) infection with access to antiretroviral medications, as the risk for AIDS has fallen and life expectancy improved. Traditional CVD risk...

  5. Schmallenberg virus infection of ruminants: challenges and opportunities for veterinarians

    Directory of Open Access Journals (Sweden)

    Claine F

    2015-06-01

    Full Text Available François Claine, Damien Coupeau, Laetitia Wiggers, Benoît Muylkens, Nathalie Kirschvink Veterinary Department, Faculty of Sciences, Namur Research Institute for Life Sciences (NARILIS, University of Namur (UNamur, Namur, Belgium Abstract: In 2011, European ruminant flocks were infected by Schmallenberg virus (SBV leading to transient disease in adult cattle but abortions and congenital deformities in calves, lambs, and goat kids. SBV belonging to the Simbu serogroup (family Bunyaviridae and genus Orthobunyavirus was first discovered in the same region where bluetongue virus serotype 8 (BTV-8 emerged 5 years before. Both viruses are transmitted by biting midges (Culicoides spp. and share several similarities. This paper describes the current knowledge of temporal and geographical spread, molecular virology, transmission and susceptible species, clinical signs, diagnosis, prevention and control, impact on ruminant health, and productivity of SBV infection in Europe, and compares SBV infection with BTV-8 infection in ruminants. Keywords: Schmallenberg virus, Europe, ruminants, review

  6. Infection of Avian Pox Virus in Oriental Turtle-Doves

    Directory of Open Access Journals (Sweden)

    Kyung-Yeon Eo1, Young-Hoan Kim2, Kwang-Hyun Cho3, Jong-Sik Jang4, Tae-Hwan Kim5, Dongmi Kwak5 and Oh-Deog Kwon5*

    2011-10-01

    Full Text Available Three Oriental Turtle-doves (Streptopelia orientalis exhibiting lethargy, dyspnea, poor physical condition, and poor flight endurance, were rescued and referred to the Animal Health Center, Seoul Zoo, Korea. The doves had wart-like lesions on the legs and head. All of them died the following day after arrival, with the exception of one that survived for 6 days. Diphtheritic membranes on the tongue and oral mucosa were apparent at necropsy. Avian pox virus infection was suspected based on the proliferative skin lesions and oral diphtheritic lesions. Infection of the avian pox virus was confirmed by PCR using primers specific to the 4b core protein gene of avian pox virus. All cases were diagnosed with avian pox virus infection. This is believed to be the first description on natural infection of avian pox in Oriental Turtle-doves in Korea.

  7. The Impact of Wolbachia on Virus Infection in Mosquitoes.

    Science.gov (United States)

    Johnson, Karyn N

    2015-11-04

    Mosquito-borne viruses such as dengue, West Nile and chikungunya viruses cause significant morbidity and mortality in human populations. Since current methods are not sufficient to control disease occurrence, novel methods to control transmission of arboviruses would be beneficial. Recent studies have shown that virus infection and transmission in insects can be impeded by co-infection with the bacterium Wolbachia pipientis. Wolbachia is a maternally inherited endosymbiont that is commonly found in insects, including a number of mosquito vector species. In Drosophila, Wolbachia mediates antiviral protection against a broad range of RNA viruses. This discovery pointed to a potential strategy to interfere with mosquito transmission of arboviruses by artificially infecting mosquitoes with Wolbachia. This review outlines research on the prevalence of Wolbachia in mosquito vector species and the impact of antiviral effects in both naturally and artificially Wolbachia-infected mosquitoes.

  8. Genus Phyllanthus for chronic hepatitis B virus infection

    DEFF Research Database (Denmark)

    Liu, J; Lin, Haili; McIntosh, H

    2001-01-01

    To evaluate the efficacy and safety of genus Phyllanthus for chronic hepatitis B virus (HBV) infection we performed a systematic review of randomized clinical trials. Randomized trials comparing genus Phyllanthus vs. placebo, no intervention, general nonspecific treatment, other herbal medicine...

  9. The Variegate Neurological Manifestations of Varicella Zoster Virus Infection

    OpenAIRE

    Gilden, Don; Nagel, Maria A.; Cohrs, Randall J; Ravi MAHALINGAM

    2013-01-01

    Varicella zoster virus (VZV) is an exclusively human neurotropic alphaherpesvirus. Primary infection causes varicella (chickenpox), after which the virus becomes latent in ganglionic neurons along the entire neuraxis. With advancing age or immunosuppression, cell-mediated immunity to VZV declines, and the virus reactivates to cause zoster (shingles), dermatomal distribution, pain, and rash. Zoster is often followed by chronic pain (postherpetic neuralgia), cranial nerve palsies, zoster paresi...

  10. The Human Immunodeficiency Virus: Infectivity and Mechanisms of Pathogenesis.

    Science.gov (United States)

    Fauci, Anthony S.

    1988-01-01

    Discusses how the infection of the human immunodeficiency virus (HIV) results in a profound immunosuppression due predominantly to a selective depletion of helper/inducer T lymphocytes that express the receptor for the virus, as well as neuropsychiatric abnormalities in the brain. (TW)

  11. Serious invasive Saffold virus infections in children, 2009

    DEFF Research Database (Denmark)

    Nielsen, Alex Christian Yde; Böttiger, Blenda; Banner, Jytte

    2012-01-01

    The first human virus in the genus Cardiovirus was described in 2007 and named Saffold virus (SAFV). Cardioviruses can cause severe infections of the myocardium and central nervous system in animals, but SAFV has not yet been convincingly associated with disease in humans. To study a possible...

  12. Herpes Simplex Virus 1 Infection on a Reconstructive Free Flap

    OpenAIRE

    Parys, Simon P.; Leman, Thea; Gurfinkel, Reuven

    2013-01-01

    Objective: Herpes simplex virus 1 (HSV1) is a widespread virus that primarily causes orofacial infection. Methods: We present a case of HSV1 infection on a free radial forearm flap used to reconstruct a palate defect. Initially, the free flap appeared healthy; however, after 48 hours the free flap appeared in distress, with dark red colour and fast capillary refill. Venous congestion was suspected, and the patient underwent a second operation where no vascular compromise was found. Vesicles w...

  13. Easy and Rapid Detection of Mumps Virus by Live Fluorescent Visualization of Virus-Infected Cells.

    Directory of Open Access Journals (Sweden)

    Tadanobu Takahashi

    Full Text Available Mumps viruses show diverse cytopathic effects (CPEs of infected cells and viral plaque formation (no CPE or no plaque formation in some cases depending on the viral strain, highlighting the difficulty in mumps laboratory studies. In our previous study, a new sialidase substrate, 2-(benzothiazol-2-yl-4-bromophenyl 5-acetamido-3,5-dideoxy-α-D-glycero-D-galacto-2-nonulopyranosidonic acid (BTP3-Neu5Ac, was developed for visualization of sialidase activity. BTP3-Neu5Ac can easily and rapidly perform histochemical fluorescent visualization of influenza viruses and virus-infected cells without an antiviral antibody and cell fixation. In the present study, the potential utility of BTP3-Neu5Ac for rapid detection of mumps virus was demonstrated. BTP3-Neu5Ac could visualize dot-blotted mumps virus, virus-infected cells, and plaques (plaques should be called focuses due to staining of infected cells in this study, even if a CPE was not observed. Furthermore, virus cultivation was possible by direct pick-up from a fluorescent focus. In conventional methods, visible appearance of the CPE and focuses often requires more than 6 days after infection, but the new method with BTP3-Neu5Ac clearly visualized infected cells after 2 days and focuses after 4 days. The BTP3-Neu5Ac assay is a precise, easy, and rapid assay for confirmation and titration of mumps virus.

  14. Recombinant vesicular stomatitis virus-based vaccines against Ebola and Marburg virus infections.

    Science.gov (United States)

    Geisbert, Thomas W; Feldmann, Heinz

    2011-11-01

    The filoviruses, Marburg virus and Ebola virus, cause severe hemorrhagic fever with a high mortality rate in humans and nonhuman primates. Among the most-promising filovirus vaccines under development is a system based on recombinant vesicular stomatitis virus (rVSV) that expresses a single filovirus glycoprotein (GP) in place of the VSV glycoprotein (G). Importantly, a single injection of blended rVSV-based filovirus vaccines was shown to completely protect nonhuman primates against Marburg virus and 3 different species of Ebola virus. These rVSV-based vaccines have also shown utility when administered as a postexposure treatment against filovirus infections, and a rVSV-based Ebola virus vaccine was recently used to treat a potential laboratory exposure. Here, we review the history of rVSV-based vaccines and pivotal animal studies showing their utility in combating Ebola and Marburg virus infections.

  15. Hepatitis B virus infection in Nigeria - A review

    Directory of Open Access Journals (Sweden)

    G O Emechebe

    2009-01-01

    Full Text Available Background:Hepatitis B virus infection is a pandemic and chronic infection may lead to chronic liver diseases which are often lethal. This review was done to assess the status of hepatitis B virus infection in Nigeria. Materials and Method:Source of information was mainly from published works in Nigeria and elsewhere. The information was extracted over period of 5 months from May to December 2007. Result: Since over 30years when pioneer works were done in Nigeria to the recent tunes the prevalence of hepatitis B virus infection has remained very high. In Nigeria, the transmission of hepatitis B virus occurs mainly during childhood and all the risk factors (like blood transfusion, sexual promiscuity, lower socioecomic status etc implicated elsewhere in the spread of the virus in the general population also play role in Nigeria. Conclusion: Reduction in the of hepatitis B virus infection could be achieved by public enlightenment campaign, mass immunization of the children and adults at risk while antiviral drugs and immunostimulatory therapy should be provided for those already infected.

  16. Experimental St. Louis encephalitis virus infection of sloths and cormorants.

    Science.gov (United States)

    Seymour, C; Kramer, L D; Peralta, P H

    1983-07-01

    Experimental infection of 11 Bradypus variegatus and Choloepus hoffmanni sloths with St. Louis encephalitis (SLE) virus produced detectable viremias of seven to 27 (median 13) days duration and maximum titers of 2.7 to 6.5 (median 5.1) log10 median suckling mouse intracranial lethal doses (SMicLD50) per ml. Experimental SLE viremia onset was delayed and maximum titer depressed in two sloths concurrently infected with naturally acquired viruses. SLE viremias in four experimentally inoculated cormorants Phalacrocorax olivaceus were shorter, and of equal or lower titer, than in sloths. Colonized Culex pipiens quinquefasciatus mosquitoes were infected by feeding on sloths circulating at least 4.8 log10 SMicLD50 of SLE virus per ml, and subsequently transmitted the infection to mice and chicks. An uninoculated baby Bradypus became infected by contact transmission from its mother. The antibody response of sloths to SLE virus was slow, being undetectable until several weeks post-inoculation. However, both sloth species developed high and long-lasting neutralizing and hemagglutination-inhibition antibody titers. The complement-fixation antibody response in Bradypus was lower and slower to develop than in Choloepus. Sloths with naturally acquired SLE virus antibody did not become detectably viremic after experimental inoculation. Neither sloths nor cormorants become overly ill from SLE virus infection.

  17. Occurrence and distribution of viruses infecting the bean in Serbia

    Directory of Open Access Journals (Sweden)

    Petrović Dragana

    2010-01-01

    Full Text Available This work describes the incidence and distribution of the most important bean viruses in Serbia: Bean common mosaic virus (BCMV, Bean common mosaic necrosis virus (BCMNV, Bean yellow mosaic virus (BYMV, Cucumber mosaic virus (CMV and Alfalfa mosaic virus (AMV. The viral isolates were characterized serologically and biologically. BCMV was found in the largest number of plants (30.53%, followed by BCMNV (2.67%, CMV (5.34%, and AMV (3.41%, since BYMV was not determined. Mixed viral infections were found in several samples. The RT-PCR method was used to prove that the tested isolates belong to the BCMV, family Potyviridae and strains Russian and NL-3 D. Results obtained in this work will enable further studies of the genetic variability of bean virus isolates from Serbia. .

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

    Science.gov (United States)

    Abrao, Emiliana Pereira; da Fonseca, Benedito Antônio Lopes

    2016-02-01

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

  19. UV radiation and mouse models of herpes simplex virus infection

    Energy Technology Data Exchange (ETDEWEB)

    Norval, Mary; El-Ghorr, A.A. [Edinburgh Univ. Medical School (United Kingdom). Dept. of Medical Microbiology

    1996-08-01

    Orolabial human infections with herpes simplex virus type 1 (HSV-1) are very common; following the primary epidermal infection, the virus is retained in a latent form in the trigeminal ganglia from where it can reactivate and cause a recrudescent lesion. Recrudescences are triggered by various stimuli including exposure to sunlight. In this review three categories of mouse models are used to examine the effects of UV irradiation on HSV infections: these are UV exposure prior to primary infection, UV exposure as a triggering event for recrudescence and UV exposure prior to challenge with virus is mice already immunized to HSV. In each of these models immunosuppression occurs, which is manifest, in some instances, in increased morbidity or an increased rate of recrudescence. Where known, the immunological mechanisms involved in the models are summarized and their relevance to human infections considered. (Author).

  20. First case of imported Zika virus infection in Spain.

    Science.gov (United States)

    Bachiller-Luque, Pablo; Domínguez-Gil González, Marta; Álvarez-Manzanares, Jesús; Vázquez, Ana; De Ory, Fernando; Sánchez-Seco Fariñas, M Paz

    2016-04-01

    We report a case of Zika virus (ZIKV) infection in a patient with diarrhea, fever, synovitis, non-purulent conjunctivitis, and with discreet retro-orbital pain, after returning from Colombia in January 2016. The patient referred several mosquito bites. Presence of ZIKV was detected by PCR (polymerase chain reaction) in plasma. Rapid microbiological diagnosis of ZIKV infection is needed in European countries with circulation of its vector, in order to avoid autochthonous circulation. The recent association of ZIKV infection with abortion and microcephaly, and a Guillain-Barré syndrome highlights the need for laboratory differentiation of ZIKV from other virus infection. Women with potential risk for Zika virus infection who are pregnant or planning to become pregnant must mention that fact during prenatal visits in order to be evaluated and properly monitored.

  1. Effects of acute respiratory virus infection upon tracheal mucous transport

    Energy Technology Data Exchange (ETDEWEB)

    Gerrard, C.S.; Levandowski, R.A.; Gerrity, T.R.; Yeates, D.B.; Klein, E.

    Tracheal mucous velocity was measured in 13 healthy non-smokers using an aerosol labelled with /sup 99m/Tc and a multidetector probe during respiratory virus infections. The movement of boluses of tracheal mucous were either absent or reduced in number in five subjects with myxovirus infection (four influenza and one respiratory syncytial virus) within 48 hr of the onset of symptoms and in four subjects 1 wk later. One subject with influenza still had reduced bolus formation 12-16 wk after infection. Frequent coughing was a feature of those subjects with absent tracheal boluses. In contrast, four subjects with rhinovirus infection had normal tracheal mucous velocity at 48 hr after the onset of symptoms (4.1 +/- 1.3 mm/min). Tracheal mucous velocity was also normal (4.6 +/- 1.1 mm/min) in four subjects in whom no specific viral agent could be defined but had typical symptomatology of respiratory viral infection. During health tracheal mucous velocity was normal (4.8 +/- 1.6 mm/min) in the eleven subjects who had measurements made. Disturbances in tracheal mucous transport during virus infection appear to depend upon the type of virus and are most severe in influenza A and respiratory syncytial virus infection.

  2. Canine distemper virus infection in a lesser grison (Galictis cuja: first report and virus phylogeny

    Directory of Open Access Journals (Sweden)

    Jane Megid

    2013-02-01

    Full Text Available Infectious diseases in wild animals have been increasing as a result of their habitat alterations and closer contact with domestic animals. Canine distemper virus (CDV has been reported in several species of wild carnivores, presenting a threat to wildlife conservation. We described the first case of canine distemper virus infection in lesser grison (Galictis cuja. A free-ranging individual, with no visible clinical sigs, presented sudden death after one day in captivity. Molecular diagnosis for CDV infection was performed using whole blood collected by postmortem intracardiac puncture, which resulted positive. The virus phylogeny indicated that domestic dogs were the probable source of infection.

  3. Regional aggressive root resorption caused by neuronal virus infection

    DEFF Research Database (Denmark)

    Kjær, Inger; Strøm, Carsten; Worsaae, Nils

    2012-01-01

    of the patients was treated with dental implants. Virus spreading along nerve paths is a possible explanation for the unexpected resorptions. In both cases, the resorptions began cervically. The extent of the resorption processes in the dentition followed the virus infected nerve paths and the resorption process...... stopped when reaching regions that were innervated differently and not infected by virus. In one case, histological examination revealed multinuclear dentinoclasts. The pattern of resorption in the two cases indicates that innervation is a factor, which under normal conditions may protect the root surface...

  4. Cats as a potential source of emerging influenza virus infections

    Institute of Scientific and Technical Information of China (English)

    Taisuke; Horimoto; Fumihiro; Gen; Shin; Murakami; Kiyoko; Iwatsuki-Horimoto; Kentaro; Kato; Masaharu; Hisasue; Masahiro; Sakaguchi; Chairul; A.; Nidom; Yoshihiro; Kawaoka

    2015-01-01

    <正>Dear Editor,Historically,the influenza virus has not been regarded as a major pathogen of cats.However,since 2003,natural infections of domestic cats with highly pathogenic H5N1 avian virus causing fatal cases have been reported(Songserm et al.,2006;Yingst et al.,2006;Klopfleisch et al.,2007).Furthermore,infections of this animal with A(H1N1)pdm09 virus,causing respiratory illness with some fatal cases,have also been reported in various parts

  5. Chronic West Nile virus infection in kea (Nestor notabilis).

    Science.gov (United States)

    Bakonyi, Tamás; Gajdon, Gyula K; Schwing, Raoul; Vogl, Wolfgang; Häbich, Annett-Carolin; Thaller, Denise; Weissenböck, Herbert; Rudolf, Ivo; Hubálek, Zdenek; Nowotny, Norbert

    2016-02-01

    Six kea (Nestor notabilis) in human care, naturally infected with West Nile virus (WNV) lineage 2 in Vienna, Austria, in 2008, developed mild to fatal neurological signs. WNV RNA persisted and the virus evolved in the birds' brains, as demonstrated by (phylo)genetic analyses of the complete viral genomes detected in kea euthanized between 2009 and 2014. WNV antibodies persisted in the birds, too. Chronic WNV infection in the brain might contribute to the circulation of the virus through oral transmission to predatory birds.

  6. Alarming incidence of hepatitis C virus re-infection after treatment of sexually acquired acute hepatitis C virus infection in HIV-infected MSM

    NARCIS (Netherlands)

    F.A.E. Lambers; M. Prins; X. Thomas; R. Molenkamp; D. Kwa; K. Brinkman; J.T.M. van der Meer; J. Schinkel

    2011-01-01

    Recent data indicate that seroprevalence of sexually transmitted hepatitis C virus (HCV) infection among MSM is stabilizing in Amsterdam. However, little is known about the incidence of HCV re-infection in MSM who have cleared their HCV infection. We, therefore, studied the incidence of re-infection

  7. Experimental evidence of hepatitis A virus infection in pigs.

    Science.gov (United States)

    Song, Young-Jo; Park, Woo-Jung; Park, Byung-Joo; Kwak, Sang-Woo; Kim, Yong-Hyeon; Lee, Joong-Bok; Park, Seung-Yong; Song, Chang-Seon; Lee, Sang-Won; Seo, Kun-Ho; Kang, Young-Sun; Park, Choi-Kyu; Song, Jae-Young; Choi, In-Soo

    2016-04-01

    Hepatitis A virus (HAV) is the leading cause of acute viral hepatitis worldwide, with HAV infection being restricted to humans and nonhuman primates. In this study, HAV infection status was serologically determined in domestic pigs and experimental infections of HAV were attempted to verify HAV infectivity in pigs. Antibodies specific to HAV or HAV-like agents were detected in 3.5% of serum samples collected from pigs in swine farms. When the pigs were infected intravenously with 2 × 10(5) 50% tissue culture infectious dose (TCID50 ) of HAV, shedding of the virus in feces, viremia, and seroconversion were detected. In pigs orally infected with the same quantity of HAV, viral shedding was detected only in feces. HAV genomic RNA was detected in the liver and bile of intravenously infected pigs, but only in the bile of orally infected pigs. In further experiments, pigs were intravenously infected with 6 × 10(5) TCID50 of HAV. Shedding of HAV in feces, along with viremia and seroconversion, were confirmed in infected pigs but not in sentinel pigs. HAV genomic RNA was detected in the liver, bile, spleen, lymph node, and kidney of the infected pigs. HAV antigenomic RNA was detected in the spleen of one HAV-infected pig, suggesting HAV replication in splenic cells. Infiltration of inflammatory cells was observed in the livers of infected pigs but not in controls. This is the first experimental evidence to demonstrate that human HAV strains can infect pigs.

  8. Preference by a virus vector for infected plants is reversed after virus acquisition.

    Science.gov (United States)

    Rajabaskar, Dheivasigamani; Bosque-Pérez, Nilsa A; Eigenbrode, Sanford D

    2014-06-24

    Pathogens and their vectors can interact either directly or indirectly via their shared hosts, with implications for the persistence and spread of the pathogen in host populations. For example, some plant viruses induce changes in host plants that cause the aphids that carry these viruses to settle preferentially on infected plants. Furthermore, relative preference by the vector for infected plants can change to a preference for noninfected plants after virus acquisition by the vector, as has recently been demonstrated in the wheat-Rhopalosiphum padi-Barley yellow dwarf virus pathosystem. Here we document a similar dynamic in the potato-Myzus persicae (Sulzer)-Potato leaf roll virus (PLRV) pathosystem. Specifically, in a dual choice bioassay, nonviruliferous apterous M. persicae settled preferentially on or near potato plants infected with PLRV relative to noninfected (sham-inoculated) control plants, whereas viruliferous M. persicae (carrying PLRV) preferentially settled on or near sham-inoculated potato plants relative to infected plants. The change in preference after virus acquisition also occurred in response to trapped headspace volatiles, and to synthetic mimics of headspace volatile blends from PLRV-infected and sham-inoculated potato plants. The change in preference we document should promote virus spread by increasing rates of virus acquisition and transmission by the vector.

  9. The Aedes aegypti toll pathway controls dengue virus infection.

    Directory of Open Access Journals (Sweden)

    Zhiyong Xi

    2008-07-01

    Full Text Available Aedes aegypti, the mosquito vector of dengue viruses, utilizes its innate immune system to ward off a variety of pathogens, some of which can cause disease in humans. To date, the features of insects' innate immune defenses against viruses have mainly been studied in the fruit fly Drosophila melanogaster, which appears to utilize different immune pathways against different types of viruses, in addition to an RNA interference-based defense system. We have used the recently released whole-genome sequence of the Ae. aegypti mosquito, in combination with high-throughput gene expression and RNA interference (RNAi-based reverse genetic analyses, to characterize its response to dengue virus infection in different body compartments. We have further addressed the impact of the mosquito's endogenous microbial flora on virus infection. Our findings indicate a significant role for the Toll pathway in regulating resistance to dengue virus, as indicated by an infection-responsive regulation and functional assessment of several Toll pathway-associated genes. We have also shown that the mosquito's natural microbiota play a role in modulating the dengue virus infection, possibly through basal-level stimulation of the Toll immune pathway.

  10. Generation of Anti-platelet Autoantibody During Dengue Virus Infection

    Directory of Open Access Journals (Sweden)

    Huan-Yao Lei

    2008-01-01

    Full Text Available Dengue virus infection causes dengue fever, Dengue Hemorrhagic Fever (DHF and Dengue Shock Syndrome (DSS. Thrombocytopenia is common in dengue fever and is always found in DHF/DSS. The pathogenesis of thrombocytopenia is poorly understood. To further understand the relationship between anti-dengue virus antibody and anti-platelet antibody, we generated monoclonal anti-dengue virus antibodies from the dengue virus infected mice that developed transient thrombocytopenia post dengue infection. The analysis of a panel of monoclonal anti-NS-1 antibodies reveals three different patterns of platelet binding: strong, intermediate, or dull. Their isotypes are different, some are IgM while others are IgG1. Most of anti-platelet antibodies are cross-reactive with NS-1 of dengue virus and can be competitively inhibited by recombinant NS-1 protein, suggesting a molecular mimicry between dengue virus NS-1 protein and platelet. A clone, 13-F4-G5, preferentially bound activated platelets, can recognize two or three proteins around 150 kD on platelets. The binding to platelet would lyse the platelet in the presence of complement or enhance the ADP-induced platelet aggregation. Furthermore, some of these monoclonal antibodies would also react with the cellular antigens of BHK. Based on the data, we conclude that dengue virus infection induces auto anti-platelet antibodies which thereafter may involve in the manifestation of thrombocytopenia. A molecular mimicry between NS-1 and platelet is demonstrated.

  11. Identification of viruses infecting pumpkins (Cucurbita pepo L in Yugoslavia

    Directory of Open Access Journals (Sweden)

    Krstić Branka B.

    2002-01-01

    Full Text Available This study was carried out in order to identify the major viruses infecting pumpkins (Cucurbita pepogrown in Serbia. Leaf samples from virus-infected pumpkin plants were collected in mid-July 2001. Naked-seeded and hulled oil pumpkins, patty pan, zucchini and summer squash from three different locations were included (Table 1. Virus-infected plants showed different symptoms (Table 2 and Figures 1-4. Due to the great variability of the symptoms, the causal viruses could not be fully and precisely determined by visual examination only. The infected samples were tested by the biotest, as well as by two serological methods, ELISA and EBIA. Polyclonal antibodies raised against cucumber mosaic cucumovirus (CMV, zucchini yellow mosaic potyvirus (ZYMV, watermelon mosaic potyvirus 1 (WMV-1, watermelon mosaic potyvirus 2 (WMV-2 and squash mosaic comovirus (SqMV were used. In each of the 50 collected samples one or two viruses were detected (Tables 3 and 4. The most prevalent viruses infecting pumpkins were ZYMV (62% and CMV (58%. WMV-2 was extremely rare.

  12. Dengue virus life cycle : viral and host factors modulating infectivity

    NARCIS (Netherlands)

    Rodenhuis-Zybert, Izabela A.; Wilschut, Jan; Smit, Jolanda M.

    2010-01-01

    Dengue virus (DENV 1-4) represents a major emerging arthropod-borne pathogen. All four DENV serotypes are prevalent in the (sub) tropical regions of the world and infect 50-100 million individuals annually. Whereas the majority of DENV infections proceed asymptomatically or result in self-limited de

  13. Vaccination against acute respiratory virus infections and measles in man.

    NARCIS (Netherlands)

    A.D.M.E. Osterhaus (Albert); P. de Vries (Petra)

    1992-01-01

    textabstractSeveral viruses may cause more or less severe acute respiratory infections in man, some of which are followed by systemic infection. Only for influenza and measles are licensed vaccines available at present. The protection induced by influenza vaccines, which are based on inactivated who

  14. ZIKA VIRUS INFECTION; VERTICAL TRANSMISSION AND FOETAL CONGENITAL ANOMALIES.

    Science.gov (United States)

    Abbasi, Aziz-un-Nisa

    2016-01-01

    Zika virus (ZIKV) is an arbovirus belonging to flaviviridae family that includes Dengue, West Nile, and Yellow Fever among others. Zika virus was first discovered in 1947 in Zika forest of Uganda. It is a vector borne disease, which has been sporadically reported mostly from Africa, Pacific islands and Southeast Asia since its discovery. ZIKV infection presents as a mild illness with symptoms lasting for several days to a week after the bite of an infected mosquito. Majority of the patients have low grade fever, rash, headaches, joints pain, myalgia, and flu like symptoms. Pregnant women are more vulnerable to ZIKV infection and serious congenital anomalies can occur in foetus through trans-placental transmission. The gestation at which infection is acquired is important. Zika virus infection acquired in early pregnancy poses greater risk. There is no evidence so far about transmission through breast milk. Foetal microcephaly, Gillian Barre syndrome and other neurological and autoimmune syndromes have been reported in areas where Zika outbreaks have occurred. As infection is usually very mild no specific treatment is required. Pregnant women may be advised to take rest, get plenty of fluids. For fever and pain they can take antipyretics like paracetamol. So far no specific drugs or vaccines are available against Zika Virus Infection so prevention is the mainstay against this diseases. As ZIKV infection is a vector borne disease, prevention can be a multi-pronged strategy. These entail vector control interventions, personal protection, environmental sanitation and health education among others.

  15. Chronic hepatitis E virus infection in liver transplant recipients

    NARCIS (Netherlands)

    Haagsma, Elizabeth B.; van den Berg, Arie P.; Porte, Robert J.; Benne, Cornelis A.; Vennema, Harry; Reimerink, Johan H. J.; Koopmans, Marion P. G.

    2008-01-01

    Hepatitis E virus (HEV) infection is known to run a self-limiting course. Sporadic cases of acute hepatitis due to infection with HEV genotype 3, present in pig populations, are increasingly recognized. Zoonotic transmission seems infrequent. The entity of unexplained chronic hepatitis after liver t

  16. [Neurological symptoms with a hepatitis E virus infection

    NARCIS (Netherlands)

    Wardt, J. van de; Dubbelink, T.B. Olde; Visee, H.F.; Schneeberger, P.M.; Lutgens, S.P.; Eijk, J.J.J. van

    2016-01-01

    BACKGROUND: Infection with hepatitis E virus genotype 3 (HEV3) is an emerging zoonosis in the industrialized world. The infection usually proceeds asymptomatically. Extrahepatic sequelae including neurological symptoms have been described. CASE DESCRIPTION: A 52-year-old man presented at the emergen

  17. Leading edge analysis of transcriptomic changes during pseudorabies virus infection

    Science.gov (United States)

    Eight RNA samples taken from the tracheobronchial lymph nodes (TBLN) of pigs that were either infected or non-infected with a feral isolate of porcine pseudorabies virus (PRV) were used to investigate changes in gene expression related to the pathogen. The RNA was processed into fastq files for each...

  18. Analysis of resistance and tolerance to virus infection in Drosophila

    NARCIS (Netherlands)

    Merkling, S.H.; Rij, R.P. van

    2015-01-01

    Host defense to virus infection involves both resistance mechanisms that reduce viral burden and tolerance mechanisms that limit detrimental effects of infection. The fruit fly, Drosophila melanogaster, has emerged as a model for identifying and characterizing the genetic basis of resistance and tol

  19. Pulmonary disease in patients with human immunodeficiency virus infection

    DEFF Research Database (Denmark)

    Lundgren, J D; Orholm, Marianne; Lundgren, B;

    1989-01-01

    Pulmonary disease is the most important cause of morbidity and mortality in patients infected with human immunodeficiency virus (HIV). All parts of the hospital system are expected to be involved in the diagnosis and treatment of HIV infected patients in the coming years. Many different processes...

  20. Stable antigen is most effective for eliciting CD8+ T-cell responses after DNA vaccination and infection with recombinant vaccinia virus in vivo.

    Science.gov (United States)

    Schliehe, Christopher; Bitzer, Annegret; van den Broek, Maries; Groettrup, Marcus

    2012-09-01

    The induction of strong CD8(+) T-cell responses against infectious diseases and cancer has remained a major challenge. Depending on the source of antigen and the infectious agent, priming of CD8(+) T cells requires direct and/or cross-presentation of antigenic peptides on major histocompatibility complex (MHC) class I molecules by professional antigen-presenting cells (APCs). However, both pathways show distinct preferences concerning antigen stability. Whereas direct presentation was shown to efficiently present peptides derived from rapidly degraded proteins, cross-presentation is dependent on long-lived antigen species. In this report, we analyzed the role of antigen stability on DNA vaccination and recombinant vaccinia virus (VV) infection using altered versions of the same antigen. The long-lived nucleoprotein (NP) of lymphocytic choriomeningitis virus (LCMV) can be targeted for degradation by N-terminal fusion to ubiquitin or, as we show here, to the ubiquitin-like modifier FAT10. Direct presentation by cells either transfected with NP-encoding plasmids or infected with recombinant VV in vitro was enhanced in the presence of short-lived antigens. In vivo, however, the highest induction of NP-specific CD8(+) T-cell responses was achieved in the presence of long-lived NP. Our experiments provide evidence that targeting antigens for proteasomal degradation does not improve the immunogenicity of DNA vaccines and recombinant VVs. Rather, it is the long-lived antigen that is superior for the efficient activation of MHC class I-restricted immune responses in vivo. Hence, our results suggest a dominant role for antigen cross-priming in DNA vaccination and recombinant VV infection.

  1. Occult hepatitis C virus infection is more common than hepatitis B infection in maintenance hemodialysis patients

    Institute of Scientific and Technical Information of China (English)

    Pankaj Jain; Sandeep Nijhawan

    2008-01-01

    Patients of end stage renal disease on maintenance hemodialysis were enrolled to study the prevalence of occult and dual hepatitis B virus (HBV) and hepatitis C virus (HCV) infection and non-occult hepatitis B and C virus infection. One hundred and two patients were enrolled. Thirty patients had HCV infection, three of them were positive in anti-HCV. So, 27 (90%) of HCVpositive patients had occult HCV infection. Eleven (11%)patients had HBV infection. Five patients were positive in anti-HBc or HBV-DNA, but negative in HBsAg (occult HBV infection). Three (3%) patients had dual HBV and HCV infection. None of the patients showed changes in viral markers during the follow-up of 8 mo on average (1-12 mo).

  2. Neuromuscular Manifestations of West Nile Virus Infection

    Directory of Open Access Journals (Sweden)

    A. Arturo eLeis

    2012-03-01

    Full Text Available The most common neuromuscular manifestation of West Nile virus (WNV infection is a poliomyelitis syndrome with asymmetric paralysis variably involving one (monoparesis to four limbs (quadriparesis, with or without brainstem involvement and respiratory failure. This syndrome of acute flaccid paralysis may occur without overt fever or meningoencephalitis. Although involvement of anterior horn cells in the spinal cord and motor neurons in the brainstem are the major sites of pathology responsible for neuromuscular signs, inflammation also may involve skeletal or cardiac muscle (myositis, myocarditis, motor axons (polyradiculitis, peripheral nerve (Guillain-Barré syndrome, brachial plexopathy. In addition, involvement of spinal sympathetic neurons and ganglia provides a plausible explanation for autonomic instability seen in some patients. Many patients also experience prolonged subjective generalized weakness and disabling fatigue. Despite recent evidence that WNV may persist long term in the central nervous system or periphery in animals, the evidence in humans is controversial. WNV persistence would be of great concern in immunosuppressed patients or in those with prolonged or recurrent symptoms. Support for the contention that WNV can lead to autoimmune disease arises from reports of patients presenting with various neuromuscular diseases that presumably involve autoimmune mechanisms (GBS, other demyelinating neu¬ropathies, myasthenia gravis, brachial plexopathies, stiff-person syndrome, and delayed or recurrent symptoms. Although there is no specific treatment or vaccine currently approved in humans, and the standard remains supportive care, drugs that can alter the cascade of immunobiochemical events leading to neuronal death may be potentially useful (high-dose corticosteroids, interferon preparations, and intravenous immune globulin containing WNV-specific antibodies. Human experience with these agents seems promising based on anecdotal

  3. Acute kidney injury in dengue virus infection

    Science.gov (United States)

    Khalil, Muhammad A.M.; Sarwar, Sarfaraz; Chaudry, Muhammad A.; Maqbool, Baila; Khalil, Zarghoona; Tan, Jackson; Yaqub, Sonia; Hussain, Syed A.

    2012-01-01

    Background Dengue is a growing public health problem in Pakistan and acute kidney injury (AKI) is one of the least studied complications of dengue virus infection (DVI). The aim of this study was to determine the frequency, severity and predictors of AKI in patients with DVI and to study the impact of AKI on the length of hospital stay and mortality. Methods We retrospectively reviewed medical records of patients aged ≥14 years hospitalized with a primary diagnosis of DVI at Aga Khan University Hospital Karachi between January 2008 and December 2010. Binary logistic regression models were constructed to identify factors associated with the development of AKI and to study the impact of AKI on hospital stays of more than 3 days. Results Out of 532 patients, AKI was present in 13.3% (71/532). Approximately two-thirds (64.8%) of these patients had mild AKI and a third (35.2%) had moderate to severe AKI. Independent predictors for AKI were male gender [odds ratio (OD) 4.43; 95% CI 1.92–10.23], presence of dengue hemorrhagic and dengue shock syndrome (DSS, OD 2.14; 95% CI 1.06–4.32), neurological involvement (OD 12.08; 95% CI 2.82–51.77) and prolonged activated partial thromboplastin time (aPTT, OD 1.81; 95% CI 1.003–3.26). AKI was associated with a length of stay ≥3 days when compared with those who did not have AKI (OD 2.98; 95% CI 1.66–5.34). Eight patients (11.3%) with AKI died whereas there were no mortalities in patients without AKI (P < 0.001). Only 5 patients (7%) had persistent kidney dysfunction at discharge. Conclusions AKI in DVI is associated with neurological involvement, prolongation of aPTT, greater length of hospital stay and increased mortality. PMID:26019813

  4. Virus-induced secondary bacterial infection: a concise review

    Directory of Open Access Journals (Sweden)

    Hendaus MA

    2015-08-01

    Full Text Available Mohamed A Hendaus,1 Fatima A Jomha,2 Ahmed H Alhammadi3 1Department of Pediatrics, Academic General Pediatrics Division, Weill-Cornell Medical College, Hamad Medical Corporation, Doha, Qatar; 2School of Pharmacy, Lebanese International University, Khiara, Lebanon; 3Department of Pediatrics, Academic General Pediatrics Division, Weill-Cornell Medical College, Hamad Medical Corporation, Doha, Qatar Abstract: Respiratory diseases are a very common source of morbidity and mortality among children. Health care providers often face a dilemma when encountering a febrile infant or child with respiratory tract infection. The reason expressed by many clinicians is the trouble to confirm whether the fever is caused by a virus or a bacterium. The aim of this review is to update the current evidence on the virus-induced bacterial infection. We present several clinical as well in vitro studies that support the correlation between virus and secondary bacterial infections. In addition, we discuss the pathophysiology and prevention modes of the virus–bacterium coexistence. A search of the PubMed and MEDLINE databases was carried out for published articles covering bacterial infections associated with respiratory viruses. This review should provide clinicians with a comprehensive idea of the range of bacterial and viral coinfections or secondary infections that could present with viral respiratory illness. Keywords: bacteria, infection, risk, virus

  5. Virus enrichment for single virus infection by using 3D insulator based dielectrophoresis.

    Science.gov (United States)

    Masuda, Taisuke; Maruyama, Hisataka; Honda, Ayae; Arai, Fumihito

    2014-01-01

    We developed an active virus filter (AVF) that enables virus enrichment for single virus infection, by using insulator-based dielectrophoresis (iDEP). A 3D-constricted flow channel design enabled the production of an iDEP force in the microfluidic chip. iDEP using a chip with multiple active virus filters (AVFs) was more accurate and faster than using a chip with a single AVF, and improved the efficiency of virus trapping. We utilized maskless photolithography to achieve the precise 3D gray-scale exposure required for fabrication of constricted flow channel. Influenza virus (A PR/8) was enriched by a negative DEP force when sinusoidal wave was applied to the electrodes within an amplitude range of 20 Vp-p and a frequency of 10 MHz. AVF-mediated virus enrichment can be repeated simply by turning the current ON or OFF. Furthermore, the negative AVF can inhibit virus adhesion onto the glass substrate. We then trapped and transported one of the enriched viruses by using optical tweezers. This microfluidic chip facilitated the effective transport of a single virus from AVFs towards the cell-containing chamber without crossing an electrode. We successfully transported the virus to the cell chamber (v = 10 µm/s) and brought it infected with a selected single H292 cell.

  6. Virus enrichment for single virus infection by using 3D insulator based dielectrophoresis.

    Directory of Open Access Journals (Sweden)

    Taisuke Masuda

    Full Text Available We developed an active virus filter (AVF that enables virus enrichment for single virus infection, by using insulator-based dielectrophoresis (iDEP. A 3D-constricted flow channel design enabled the production of an iDEP force in the microfluidic chip. iDEP using a chip with multiple active virus filters (AVFs was more accurate and faster than using a chip with a single AVF, and improved the efficiency of virus trapping. We utilized maskless photolithography to achieve the precise 3D gray-scale exposure required for fabrication of constricted flow channel. Influenza virus (A PR/8 was enriched by a negative DEP force when sinusoidal wave was applied to the electrodes within an amplitude range of 20 Vp-p and a frequency of 10 MHz. AVF-mediated virus enrichment can be repeated simply by turning the current ON or OFF. Furthermore, the negative AVF can inhibit virus adhesion onto the glass substrate. We then trapped and transported one of the enriched viruses by using optical tweezers. This microfluidic chip facilitated the effective transport of a single virus from AVFs towards the cell-containing chamber without crossing an electrode. We successfully transported the virus to the cell chamber (v = 10 µm/s and brought it infected with a selected single H292 cell.

  7. Active Epstein-Barr virus infection after allogeneic stem cell transplantation : re-infection or reactivation?

    NARCIS (Netherlands)

    Meijer, E; Spijkers, S; Moschatsis, S; Boland, GJ; Thijsen, SFT; van Loon, AM; Verdonck, LF

    2005-01-01

    Recipients of allogeneic stem cell transplants (SCT) often show active Epstein-Barr virus (EBV) infection, which may progress to EBV-associated lymphoproliferative disorders. It is not known whether these EBV infections are true reactivations of the endogenous EBV strain or re-infections with an exo

  8. Research on viral dynamic models of hepatitis B virus infection

    Institute of Scientific and Technical Information of China (English)

    Lequan Min; Xisong Dong

    2004-01-01

    A mathematical model with cytotoxic cells of hepatitis B virus (HBV) infection is set up based on a basic model of virus dynamics without cytotoxic cells and experimental observation of anti-viral drug therapy for HBV infection patients. A quantitative analysis of dynamic behaviors shows that the model has three kinds of equilibrium points, which represent the patient's complete recovery without immune ability, complete recovery with immune ability, and HBV persistent infection at the end of the treatment with drug lamivudine, respectively. Our model may provide possible quantitative interpretations for the treatments of chronic HBV infections with the drug lamivudine, in particularly explain why the plasma virus of Nowak et al.'s patients turnover the original level after stopping the lamivudine treatment.

  9. Early Events in Chikungunya Virus Infection-From Virus Cell Binding to Membrane Fusion.

    Science.gov (United States)

    van Duijl-Richter, Mareike K S; Hoornweg, Tabitha E; Rodenhuis-Zybert, Izabela A; Smit, Jolanda M

    2015-07-07

    Chikungunya virus (CHIKV) is a rapidly emerging mosquito-borne alphavirus causing millions of infections in the tropical and subtropical regions of the world. CHIKV infection often leads to an acute self-limited febrile illness with debilitating myalgia and arthralgia. A potential long-term complication of CHIKV infection is severe joint pain, which can last for months to years. There are no vaccines or specific therapeutics available to prevent or treat infection. This review describes the critical steps in CHIKV cell entry. We summarize the latest studies on the virus-cell tropism, virus-receptor binding, internalization, membrane fusion and review the molecules and compounds that have been described to interfere with virus cell entry. The aim of the review is to give the reader a state-of-the-art overview on CHIKV cell entry and to provide an outlook on potential new avenues in CHIKV research.

  10. Interferon Response in Hepatitis C Virus (HCV) Infection: Lessons from Cell Culture Systems of HCV Infection.

    Science.gov (United States)

    Sung, Pil Soo; Shin, Eui-Cheol; Yoon, Seung Kew

    2015-01-01

    Hepatitis C virus (HCV) is a positive-stranded RNA virus that infects approximately 130-170 million people worldwide. In 2005, the first HCV infection system in cell culture was established using clone JFH-1, which was isolated from a Japanese patient with fulminant HCV infection. JFH-1 replicates efficiently in hepatoma cells and infectious virion particles are released into the culture supernatant. The development of cell culture-derived HCV (HCVcc) systems has allowed us to understand how hosts respond to HCV infection and how HCV evades host responses. Although the mechanisms underlying the different outcomes of HCV infection are not fully understood, innate immune responses seem to have a critical impact on the outcome of HCV infection, as demonstrated by the prognostic value of IFN-λ gene polymorphisms among patients with chronic HCV infection. Herein, we review recent research on interferon response in HCV infection, particularly studies using HCVcc infection systems.

  11. Virus and host factors affecting the clinical outcome of Bluetongue Virus infection

    NARCIS (Netherlands)

    Caporale, M.; Gialleonorado, L.; Janowicz, A.; Wilkie, G.; Shaw, A.; Savini, G.; Rijn, van P.A.; Mertens, P.; Ventura, M.; Palmarini, M.

    2014-01-01

    Bluetongue is a major infectious disease of ruminants caused by bluetongue virus (BTV), an arbovirus transmitted by Culicoides. Here, we assessed virus and host factors influencing the clinical outcome of BTV infection using a single experimental framework. We investigated how mammalian host species

  12. Identification of a pegivirus (GB virus-like virus) that infects horses

    DEFF Research Database (Denmark)

    Kapoor, Amit; Simmonds, Peter; Cullen, John M

    2013-01-01

    The recent identification of nonprimate hepaciviruses in dogs and then in horses prompted us to look for pegiviruses (GB virus-like viruses) in these species. Although none were detected in canines, we found widespread natural infection of horses by a novel pegivirus. Unique genomic features...

  13. New perspectives in occult hepatitis C virus infection

    OpenAIRE

    CARREÑO, VICENTE; Bartolomé, Javier; Castillo, Inmaculada; Quiroga, Juan Antonio

    2012-01-01

    Occult hepatitis C virus (HCV) infection, defined as the presence of HCV RNA in liver and in peripheral blood mononuclear cells (PBMCs) in the absence of detectable viral RNA in serum by standard assays, can be found in anti-HCV positive patients with normal serum levels of liver enzymes and in anti-HCV negative patients with persistently elevated liver enzymes of unknown etiology. Occult HCV infection is distributed worldwide and all HCV genotypes seem to be involved in this infection. Occul...

  14. Emerging Zika virus infection:What should we know?

    Institute of Scientific and Technical Information of China (English)

    Viroj Wiwanitkit

    2016-01-01

    Zika virus infection is a new emerging viral disease that becomes the present public health threat. At present, this infection can be seen in several countries. The clinical presentation of this infection is a dengue-like illness. Nevertheless, the new information shows that the disease can be sexually transmitted and transplacentally transmitted. In addition, the recent evidence from the recent epidemic in South America shows that the infection in pregnancy can cause neonatal neurological defect. In this short review, the author summarizes and presents interesting data on clinical features of this new emerging infection.

  15. Emerging Zika virus infection: What should we know?

    Directory of Open Access Journals (Sweden)

    Viroj Wiwanitkit

    2016-07-01

    Full Text Available Zika virus infection is a new emerging viral disease that becomes the present public health threat. At present, this infection can be seen in several countries. The clinical presentation of this infection is a dengue-like illness. Nevertheless, the new information shows that the disease can be sexually transmitted and transplacentally transmitted. In addition, the recent evidence from the recent epidemic in South America shows that the infection in pregnancy can cause neonatal neurological defect. In this short review, the author summarizes and presents interesting data on clinical features of this new emerging infection.

  16. Why Zika virus infection has become a public health concern?

    Science.gov (United States)

    Chen, Hui-Lan; Tang, Ren-Bin

    2016-04-01

    Prior to 2015, Zika Virus (ZIKV) outbreaks had occurred in areas of Africa, Southeast Asia, and the Pacific Islands. Although a causal relationship between Zika infection during pregnancy and microcephaly is strongly suspected, such a connection has not yet been scientifically proven. In May 2015, the outbreak of ZIKV infection in Brazil led to reports of syndrome and pregnant women giving birth to babies with birth defects and poor pregnancy outcomes; the Pan American Health Organization (PAHO) issued an alert regarding the first confirmed ZIKV infection in Brazil. Currently, ZIKV outbreaks are ongoing and it will be difficult to predict how the virus will spread over time. ZIKV is transmitted to humans primarily through the bite of infected mosquitos, Aedes aegypti and Aedes albopictus. These mosquitoes are the principle vectors of dengue, and ZIKV disease generally is reported to include symptoms associated with acute febrile illnesses that clinically resembles dengue fever. The laboratory diagnosis can be performed by using reverse-transcriptase polymerase chain reaction (RT-PCR) on serum, viral nucleic acid and virus-specific immunoglobulin M. There is currently no vaccine and antiviral treatment available for ZIKV infection, and the only way to prevent congenital ZIKV infection is to prevent maternal infection. In February 2016, the Taiwan Centers for Disease Control (Taiwan CDC) activated ZIKV as a Category V Notifiable Infectious Disease similar to Ebola virus disease and MERS.

  17. Antiviral activity of lanatoside C against dengue virus infection.

    Science.gov (United States)

    Cheung, Yan Yi; Chen, Karen Caiyun; Chen, Huixin; Seng, Eng Khuan; Chu, Justin Jang Hann

    2014-11-01

    Dengue infection poses a serious threat globally due to its recent rapid spread and rise in incidence. Currently, there is no approved vaccine or effective antiviral drug for dengue virus infection. In response to the urgent need for the development of an effective antiviral for dengue virus, the US Drug Collection library was screened in this study to identify compounds with anti-dengue activities. Lanatoside C, an FDA approved cardiac glycoside was identified as a candidate anti-dengue compound. Our data revealed that lanatoside C has an IC50 of 0.19μM for dengue virus infection in HuH-7 cells. Dose-dependent reduction in dengue viral RNA and viral proteins synthesis were also observed upon treatment with increasing concentrations of lanatoside C. Time of addition study indicated that lanatoside C inhibits the early processes of the dengue virus replication cycle. Furthermore, lanatoside C can effectively inhibit all four serotypes of dengue virus, flavivirus Kunjin, alphavirus Chikungunya and Sindbis virus as well as the human enterovirus 71. These findings suggest that lanatoside C possesses broad spectrum antiviral activity against several groups of positive-sense RNA viruses.

  18. Human immunodeficiency virus type 1 infection of human uterine epithelial cells: viral shedding and cell contact-mediated infectivity.

    Science.gov (United States)

    Asin, Susana N; Wildt-Perinic, Dunja; Mason, Sarah I; Howell, Alexandra L; Wira, Charles R; Fanger, Michael W

    2003-05-15

    We examined the mechanism of human immunodeficiency virus (HIV) type 1 infection of human uterine epithelial cells to gain a clearer understanding of the events by which HIV-1 infects cells within the female reproductive tract. We demonstrated that these cells can be productively infected by HIV-1 and that infection is associated with viral RNA reverse transcription, DNA transcription, and secretion of infectious virus. Levels of viral DNA and secreted virus decreased gradually after infection. Moreover, virus released by the uterine epithelial cells shortly after infection was able to infect human T cell lines, but virus released later did not. In contrast, human CD4(+) T cell lines were infected after cocultivation with epithelial cells at both early and late stages of infection. These data demonstrated that HIV-1 infects human epithelial cells of upper reproductive tract origin and that productive viral infection of epithelial cells may be an important mechanism of transmission of HIV-1 infection in women.

  19. Quantification of airborne African swine fever virus after experimental infection.

    Science.gov (United States)

    de Carvalho Ferreira, H C; Weesendorp, E; Quak, S; Stegeman, J A; Loeffen, W L A

    2013-08-30

    Knowledge on African Swine Fever (ASF) transmission routes can be useful when designing control measures against the spread of ASF virus (ASFV). Few studies have focused on the airborne transmission route, and until now no data has been available on quantities of ASF virus (ASFV) in the air. Our aim was to validate an air sampling technique for ASF virus (ASFV) that could be used to detect and quantify virus excreted in the air after experimental infection of pigs. In an animal experiment with the Brazil'78, the Malta'78 and Netherlands'86 isolates, air samples were collected at several time points. For validation of the air sampling technique, ASFV was aerosolised in an isolator, and air samples were obtained using the MD8 air scan device, which was shown to be suitable to detect ASFV. The half-life of ASFV in the air was on average 19 min when analysed by PCR, and on average 14 min when analysed by virus titration. In rooms with infected pigs, viral DNA with titres up to 10(3.2) median tissue culture infective dose equivalents (TCID50eq.)/m(3) could be detected in air samples from day 4 post-inoculation (dpi 4) until the end of the experiments, at dpi 70. In conclusion, this study shows that pigs infected with ASFV will excrete virus in the air, particularly during acute disease. This study provides the first available parameters to model airborne transmission of ASFV.

  20. Deep Sequencing Analysis of Apple Infecting Viruses in Korea

    Science.gov (United States)

    Cho, In-Sook; Igori, Davaajargal; Lim, Seungmo; Choi, Gug-Seoun; Hammond, John; Lim, Hyoun-Sub; Moon, Jae Sun

    2016-01-01

    Deep sequencing has generated 52 contigs derived from five viruses; Apple chlorotic leaf spot virus (ACLSV), Apple stem grooving virus (ASGV), Apple stem pitting virus (ASPV), Apple green crinkle associated virus (AGCaV), and Apricot latent virus (ApLV) were identified from eight apple samples showing small leaves and/or growth retardation. Nucleotide (nt) sequence identity of the assembled contigs was from 68% to 99% compared to the reference sequences of the five respective viral genomes. Sequences of ASPV and ASGV were the most abundantly represented by the 52 contigs assembled. The presence of the five viruses in the samples was confirmed by RT-PCR using specific primers based on the sequences of each assembled contig. All five viruses were detected in three of the samples, whereas all samples had mixed infections with at least two viruses. The most frequently detected virus was ASPV, followed by ASGV, ApLV, ACLSV, and AGCaV which were withal found in mixed infections in the tested samples. AGCaV was identified in assembled contigs ID 1012480 and 93549, which showed 82% and 78% nt sequence identity with ORF1 of AGCaV isolate Aurora-1. ApLV was identified in three assembled contigs, ID 65587, 1802365, and 116777, which showed 77%, 78%, and 76% nt sequence identity respectively with ORF1 of ApLV isolate LA2. Deep sequencing assay was shown to be a valuable and powerful tool for detection and identification of known and unknown virome in infected apple trees, here identifying ApLV and AGCaV in commercial orchards in Korea for the first time.

  1. Deep Sequencing Analysis of Apple Infecting Viruses in Korea.

    Science.gov (United States)

    Cho, In-Sook; Igori, Davaajargal; Lim, Seungmo; Choi, Gug-Seoun; Hammond, John; Lim, Hyoun-Sub; Moon, Jae Sun

    2016-10-01

    Deep sequencing has generated 52 contigs derived from five viruses; Apple chlorotic leaf spot virus (ACLSV), Apple stem grooving virus (ASGV), Apple stem pitting virus (ASPV), Apple green crinkle associated virus (AGCaV), and Apricot latent virus (ApLV) were identified from eight apple samples showing small leaves and/or growth retardation. Nucleotide (nt) sequence identity of the assembled contigs was from 68% to 99% compared to the reference sequences of the five respective viral genomes. Sequences of ASPV and ASGV were the most abundantly represented by the 52 contigs assembled. The presence of the five viruses in the samples was confirmed by RT-PCR using specific primers based on the sequences of each assembled contig. All five viruses were detected in three of the samples, whereas all samples had mixed infections with at least two viruses. The most frequently detected virus was ASPV, followed by ASGV, ApLV, ACLSV, and AGCaV which were withal found in mixed infections in the tested samples. AGCaV was identified in assembled contigs ID 1012480 and 93549, which showed 82% and 78% nt sequence identity with ORF1 of AGCaV isolate Aurora-1. ApLV was identified in three assembled contigs, ID 65587, 1802365, and 116777, which showed 77%, 78%, and 76% nt sequence identity respectively with ORF1 of ApLV isolate LA2. Deep sequencing assay was shown to be a valuable and powerful tool for detection and identification of known and unknown virome in infected apple trees, here identifying ApLV and AGCaV in commercial orchards in Korea for the first time.

  2. Deep Sequencing Analysis of Apple Infecting Viruses in Korea

    Directory of Open Access Journals (Sweden)

    In-Sook Cho

    2016-10-01

    Full Text Available Deep sequencing has generated 52 contigs derived from five viruses; Apple chlorotic leaf spot virus (ACLSV, Apple stem grooving virus (ASGV, Apple stem pitting virus (ASPV, Apple green crinkle associated virus (AGCaV, and Apricot latent virus (ApLV were identified from eight apple samples showing small leaves and/or growth retardation. Nucleotide (nt sequence identity of the assembled contigs was from 68% to 99% compared to the reference sequences of the five respective viral genomes. Sequences of ASPV and ASGV were the most abundantly represented by the 52 contigs assembled. The presence of the five viruses in the samples was confirmed by RT-PCR using specific primers based on the sequences of each assembled contig. All five viruses were detected in three of the samples, whereas all samples had mixed infections with at least two viruses. The most frequently detected virus was ASPV, followed by ASGV, ApLV, ACLSV, and AGCaV which were withal found in mixed infections in the tested samples. AGCaV was identified in assembled contigs ID 1012480 and 93549, which showed 82% and 78% nt sequence identity with ORF1 of AGCaV isolate Aurora-1. ApLV was identified in three assembled contigs, ID 65587, 1802365, and 116777, which showed 77%, 78%, and 76% nt sequence identity respectively with ORF1 of ApLV isolate LA2. Deep sequencing assay was shown to be a valuable and powerful tool for detection and identification of known and unknown virome in infected apple trees, here identifying ApLV and AGCaV in commercial orchards in Korea for the first time.

  3. Up-to-date knowledge of West Nile virus infection

    Directory of Open Access Journals (Sweden)

    Hrnjaković-Cvjetković Ivana

    2009-01-01

    Full Text Available Virus West Nile virus is a single-stranded RNA virus of the family Flaviviridae, genus Flavivirus. Epidemiology West Nile virus is maintained in the cycle involving culicine mosquitoes and birds .Humans typically acquire West Nile infection through a bite from infected adult mosquito. Person to person transmission can occur through organ transplantation, blood and blood product transfusions, transplacentally and via brest milk. Human cases of West Nile infections were recorded in Africa, Israel, Russia, India, Pakistan. In Romania in 1996 West Nile fever occurred with hundreds of neurologic cases and 17 fatalities. First human cases in the United States were in New York City where 59 persons were infected and had fever, meningitis, encephalitis and flaccid paralysis. Clinical manifestation Most human cases are asymptomatic. The majority of symptomatic patients have a self limited febrile illness. Fatigue, nausea, vomiting, eye pain, headache, myalgias, artralgias, lymphadenopathy and rash are common complaints. Less than 1% of all infected persons develop more severe neurologic illness including meningitis, encefalitis and flaccid paralysis. Laboratory diagnosis Diagnosis of West Nile virus infection is based on serologic testing, isolation of virus from patient samples and detection of viral antigen or viral genom. ELISA test and indirect immunofluorescenceassay are used for detecting IgM and IgG antibodies in serum and cerebrospinal fluid. Treatment In vitro studies have suggested that ribavirin and interferon alfa -2b may be useful in the treatment of West Nile virus disease. Prevention The most important measures are mosquito control program and personal protective measures. .

  4. Effects of interferons on hepatitis C virus infection

    Directory of Open Access Journals (Sweden)

    Bojić Ivanko

    2006-01-01

    Full Text Available Introduction. The consequences of hepatitis C virus infections (chronic hepatitis, liver cirrhosis and hepatocellular carcinoma are one of the major problems in clinical medicine. The persistence of infection in spite of high specific antibody titre suggests that the virus has the ability to "escape" the immunological response. Interferon therapy. Interferons are important components of the early host response to infection. They have antiviral, antiproliferative, and immunomodulatory activities. Many viruses have developed the ability to "annul" or alleviate the action of interferon by preventing its synthesis or by interfering with signaling pathways in the cells. During acute infection some of the non-structural proteins of HCV block regulatory factors that are responsible for the synthesis of endogenous infection. Within a cell, interferon induces a number of genes to produce proteins that prevent virus replication. Among them, the most important are RNA-dependent protein kinase and the eukaryotic initiation factor. However, viral proteins, especially viral envelope proteins and nonstructural protein 5A, prevent their phosphorylation and activation which enhance virus replication. These are the facts that have to be considered when using IFN in chronic hepatitis C patients. .

  5. Occult hepatitis B virus and hepatitis C virus infections.

    Science.gov (United States)

    Carreño, Vicente; Bartolomé, Javier; Castillo, Inmaculada; Quiroga, Juan Antonio

    2008-01-01

    Occult HBV infection is a well-recognised clinical entity characterised by the detection of HBV-DNA in serum and/or in liver in the absence of detectable hepatitis B surface antigen (HBsAg). Occult HBV infection has been described not only in patients who have resolved an acute or chronic HBV infection but also in patients without any serological markers of a past HBV infection. Occult HBV infection in patients with chronic HCV infection may induce more severe liver disease and lower response rate to interferon treatment. The existence of occult HCV infections has been also reported more recently. Occult HCV infection is characterised by the presence of HCV-RNA in liver and peripheral blood mononuclear cells in the absence of detectable serum HCV-RNA. Occult HCV infection may occur under two different clinical situations: in hepatitis C antibody-(anti-HCV) negative and serum HCV-RNA-negative patients with abnormal liver function tests and in anti-HCV-positive patients who have no detectable serum HCV-RNA and who have normal liver enzymes. The clinical relevance of occult HCV infections is still under investigation.

  6. Bordetella pertussis infection exacerbates influenza virus infection through pertussis toxin-mediated suppression of innate immunity.

    Directory of Open Access Journals (Sweden)

    Victor I Ayala

    Full Text Available Pertussis (whooping cough is frequently complicated by concomitant infections with respiratory viruses. Here we report the effect of Bordetella pertussis infection on subsequent influenza virus (PR8 infection in mouse models and the role of pertussis toxin (PT in this effect. BALB/c mice infected with a wild-type strain of B. pertussis (WT and subsequently (up to 14 days later infected with PR8 had significantly increased pulmonary viral titers, lung pathology and mortality compared to mice similarly infected with a PT-deficient mutant strain (ΔPT and PR8. Substitution of WT infection by intranasal treatment with purified active PT was sufficient to replicate the exacerbating effects on PR8 infection in BALB/c and C57/BL6 mice, but the effects of PT were lost when toxin was administered 24 h after virus inoculation. PT had no effect on virus titers in primary cultures of murine tracheal epithelial cells (mTECs in vitro, suggesting the toxin targets an early immune response to increase viral titers in the mouse model. However, type I interferon responses were not affected by PT. Whole genome microarray analysis of gene expression in lung tissue from PT-treated and control PR8-infected mice at 12 and 36 h post-virus inoculation revealed that PT treatment suppressed numerous genes associated with communication between innate and adaptive immune responses. In mice depleted of alveolar macrophages, increase of pulmonary viral titers by PT treatment was lost. PT also suppressed levels of IL-1β, IL-12, IFN-γ, IL-6, KC, MCP-1 and TNF-α in the airways after PR8 infection. Furthermore PT treatment inhibited early recruitment of neutrophils and NK cells to the airways. Together these findings demonstrate that infection with B. pertussis through PT activity predisposes the host to exacerbated influenza infection by countering protective innate immune responses that control virus titers.

  7. The virus-encoded chemokine vMIP-II inhibits virus-induced Tc1-driven inflammation

    DEFF Research Database (Denmark)

    Lindow, Morten; Nansen, Anneline; Bartholdy, Christina;

    2003-01-01

    virus-induced T-cell-mediated inflammation. This was done by use of the well-established model system murine lymphocytic choriomeningitis virus infection. Mice were infected in the footpad, and the induced CD8(+) T-cell-dependent inflammation was evaluated in mice subjected to treatment with vMIP-II. We...... found that inflammation was markedly inhibited in mice treated during the efferent phase of the antiviral immune response. In vitro studies revealed that vMIP-II inhibited chemokine-induced migration of activated CD8(+) T cells, but not T-cell-target cell contact, granule exocytosis, or cytokine release...... injected directly into the test site. In contrast to the marked inhibition of the effector phase, the presence of vMIP-II during the afferent phase of the immune response did not result in significant suppression of virus-induced inflammation. Taken together, these results indicate that chemokine...

  8. Pseudorabies virus infection alters neuronal activity and connectivity in vitro.

    Directory of Open Access Journals (Sweden)

    Kelly M McCarthy

    2009-10-01

    Full Text Available Alpha-herpesviruses, including human herpes simplex virus 1 & 2, varicella zoster virus and the swine pseudorabies virus (PRV, infect the peripheral nervous system of their hosts. Symptoms of infection often include itching, numbness, or pain indicative of altered neurological function. To determine if there is an in vitro electrophysiological correlate to these characteristic in vivo symptoms, we infected cultured rat sympathetic neurons with well-characterized strains of PRV known to produce virulent or attenuated symptoms in animals. Whole-cell patch clamp recordings were made at various times after infection. By 8 hours of infection with virulent PRV, action potential (AP firing rates increased substantially and were accompanied by hyperpolarized resting membrane potentials and spikelet-like events. Coincident with the increase in AP firing rate, adjacent neurons exhibited coupled firing events, first with AP-spikelets and later with near identical resting membrane potentials and AP firing. Small fusion pores between adjacent cell bodies formed early after infection as demonstrated by transfer of the low molecular weight dye, Lucifer Yellow. Later, larger pores formed as demonstrated by transfer of high molecular weight Texas red-dextran conjugates between infected cells. Further evidence for viral-induced fusion pores was obtained by infecting neurons with a viral mutant defective for glycoprotein B, a component of the viral membrane fusion complex. These infected neurons were essentially identical to mock infected neurons: no increased AP firing, no spikelet-like events, and no electrical or dye transfer. Infection with PRV Bartha, an attenuated circuit-tracing strain delayed, but did not eliminate the increased neuronal activity and coupling events. We suggest that formation of fusion pores between infected neurons results in electrical coupling and elevated firing rates, and that these processes may contribute to the altered neural

  9. Serodiagnosis of Helicobacter pylori infection in patients with human immunodeficiency virus infection

    DEFF Research Database (Denmark)

    Nielsen, H; Andersen, L P

    1995-01-01

    In contrast to the established role of Helicobacter pylori gastritis in gastritis and duodenal ulcer in general, conflicting results have been reported in patients with human immunodeficiency virus (HIV) infection and the acquired immunodeficiency syndrome. The seroprevalence during early HIV...

  10. Deep sequencing in the management of hepatitis virus infections.

    Science.gov (United States)

    Quer, Josep; Rodríguez-Frias, Francisco; Gregori, Josep; Tabernero, David; Soria, Maria Eugenia; García-Cehic, Damir; Homs, Maria; Bosch, Albert; Pintó, Rosa María; Esteban, Juan Ignacio; Domingo, Esteban; Perales, Celia

    2016-12-28

    The hepatitis viruses represent a major public health problem worldwide. Procedures for characterization of the genomic composition of their populations, accurate diagnosis, identification of multiple infections, and information on inhibitor-escape mutants for treatment decisions are needed. Deep sequencing methodologies are extremely useful for these viruses since they replicate as complex and dynamic quasispecies swarms whose complexity and mutant composition are biologically relevant traits. Population complexity is a major challenge for disease prevention and control, but also an opportunity to distinguish among related but phenotypically distinct variants that might anticipate disease progression and treatment outcome. Detailed characterization of mutant spectra should permit choosing better treatment options, given the increasing number of new antiviral inhibitors available. In the present review we briefly summarize our experience on the use of deep sequencing for the management of hepatitis virus infections, particularly for hepatitis B and C viruses, and outline some possible new applications of deep sequencing for these important human pathogens.

  11. Virus Infections on Prion Diseased Mice Exacerbate Inflammatory Microglial Response

    Science.gov (United States)

    Lins, Nara; Mourão, Luiz; Trévia, Nonata; Passos, Aline; Farias, José Augusto; Assunção, Jarila; Bento-Torres, João; Consentino Kronka Sosthenes, Marcia; Diniz, José Antonio Picanço; Vasconcelos, Pedro Fernando da Costa

    2016-01-01

    We investigated possible interaction between an arbovirus infection and the ME7 induced mice prion disease. C57BL/6, females, 6-week-old, were submitted to a bilateral intrahippocampal injection of ME7 prion strain (ME7) or normal brain homogenate (NBH). After injections, animals were organized into two groups: NBH (n = 26) and ME7 (n = 29). At 15th week after injections (wpi), animals were challenged intranasally with a suspension of Piry arbovirus 0.001% or with NBH. Behavioral changes in ME7 animals appeared in burrowing activity at 14 wpi. Hyperactivity on open field test, errors on rod bridge, and time reduction in inverted screen were detected at 15th, 19th, and 20th wpi respectively. Burrowing was more sensitive to earlier hippocampus dysfunction. However, Piry-infection did not significantly affect the already ongoing burrowing decline in the ME7-treated mice. After behavioral tests, brains were processed for IBA1, protease-resistant form of PrP, and Piry virus antigens. Although virus infection in isolation did not change the number of microglia in CA1, virus infection in prion diseased mice (at 17th wpi) induced changes in number and morphology of microglia in a laminar-dependent way. We suggest that virus infection exacerbates microglial inflammatory response to a greater degree in prion-infected mice, and this is not necessarily correlated with hippocampal-dependent behavioral deficits. PMID:28003864

  12. Innate immune targets of hepatitis B virus infection.

    Science.gov (United States)

    Zou, Zhi-Qiang; Wang, Li; Wang, Kai; Yu, Ji-Guang

    2016-06-18

    Approximately 400 million people are chronically infected with hepatitis B virus (HBV) globally despite the widespread immunization of HBV vaccine and the development of antiviral therapies. The immunopathogenesis of HBV infection is initiated and driven by complexed interactions between the host immune system and the virus. Host immune responses to viral particles and proteins are regarded as the main determinants of viral clearance or persistent infection and hepatocyte injury. Innate immune system is the first defending line of host preventing from virus invasion. It is acknowledged that HBV has developed active tactics to escape innate immune recognition or actively interfere with innate immune signaling pathways and induce immunosuppression, which favor their replication. HBV reduces the expression of pattern-recognition receptors in the innate immune cells in humans. Also, HBV may interrupt different parts of antiviral signaling pathways, leading to the reduced production of antiviral cytokines such as interferons that contribute to HBV immunopathogenesis. A full comprehension of the mechanisms as to how HBV inactivates various elements of the innate immune response to initiate and maintain a persistent infection can be helpful in designing new immunotherapeutic methods for preventing and eradicating the virus. In this review, we aimed to summarize different branches the innate immune targeted by HBV infection. The review paper provides evidence that multiple components of immune responses should be activated in combination with antiviral therapy to disrupt the tolerance to HBV for eliminating HBV infection.

  13. CD4+ T cell responses in hepatitis C virus infection

    Institute of Scientific and Technical Information of China (English)

    Nasser Semmo; Paul Klenerman

    2007-01-01

    Hepatitis C virus (HCV) infection is a major cause of liver damage, with virus-induced end-stage disease such as liver cirrhosis and hepatocellular carcinoma resulting in a high rate of morbidity and mortality worldwide. Evidence that CD4+ T cell responses to HCV play an important role in the outcome of acute infection has been shown in several studies. However, the mechanisms behind viral persistence and the failure of CD4+ T cell responses to contain virus are poorly understood. During chronic HCV infection, HCV-specific CD4+ T cell responses are relatively weak or absent whereas in resolved infection these responses are vigorous and multispecific. Persons with a T-helper type Ⅰ profile, which promotes cellular effector mechanisms are thought to be more likely to experience viral clearance, but the overall role of these cells in the immunopathogenesis of chronic liver disease is not known. To define this, much more data is required on the function and specificity of virus-specific CD4+ T cells,especially in the early phases of acute disease and in the liver during chronic infection. The role and possible mechanisms of action of CD4+ T cell responses in determining the outcome of acute and chronic HCV infection will be discussed in this review.

  14. Zika virus infections: An overview of current scenario.

    Science.gov (United States)

    Dasti, Javid Iqbal

    2016-07-01

    Zika virus (ZIKV) was discovered more than half a century ago, recently it has gained unprecedented attention by the global health community. Until 2007, only 14 cases of human ZIKV infections were reported around the globe, while during the current outbreak, estimated cases mounted to approximately 1.5 million in Brazil alone, the virus was disseminated to wider South-American territories and travel-associated ZIKV infections were reported in USA, Europe and recently in China. ZIKV infections remain asymptomatic in approximately 80% of the individuals, and no anti-viral treatments were recommended. Yet, neurological complications associated with the infections, such as infant microcephaly and Guillain-Barré syndrome are major cause of the concern. Although, based on small numbers of cases, existing evidence strongly supports an exclusive link of viral infection and observed neurological complications. However, much work remains to assign exact numbers of complications caused by ZIKV. Regarding its structural attributes ZIKV shows remarkable resemblance with dengue virus and West-Nile virus. Despite, genomes of different ZIKV strains have already been decoded; role of the viral components in infection process and particularly pathogenesis of the disease remain widely unclear. In vulnerable areas, most viable strategy to ensure public health safety is vector control and enhanced public awareness about the transmission of the disease.

  15. Innate immune targets of hepatitis B virus infection

    Institute of Scientific and Technical Information of China (English)

    Zhi-Qiang; Zou; Li; Wang; Kai; Wang; Ji-Guang; Yu

    2016-01-01

    Approximately 400 million people are chronically infected with hepatitis B virus(HBV) globally despitethe widespread immunization of HBV vaccine and the development of antiviral therapies. The immunopathogenesis of HBV infection is initiated and driven by complexed interactions between the host immune system and the virus. Host immune responses to viral particles and proteins are regarded as the main determinants of viral clearance or persistent infection and hepatocyte injury. Innate immune system is the first defending line of host preventing from virus invasion. It is acknowledged that HBV has developed active tactics to escape innate immune recognition or actively interfere with innate immune signaling pathways and induce immunosuppression, which favor their replication. HBV reduces the expression of pattern-recognition receptors in the innate immune cells in humans. Also, HBV may interrupt different parts of antiviral signaling pathways, leading to the reduced production of antiviral cytokines such as interferons that contribute to HBV immunopathogenesis. A full comprehension of the mechanisms as to how HBV inactivates various elements of the innate immune response to initiate and maintain a persistent infection can be helpful in designing new immunotherapeutic methods for preventing and eradicating the virus. In this review, we aimed to summarize different branches the innate immune targeted by HBV infection. The review paper provides evidence that multiple components of immune responses should be activated in combination with antiviral therapy to disrupt the tolerance to HBV for eliminating HBV infection.

  16. A Virus-type Specific Serological Diagnosis of Flavivirus Infection Using Virus-like Particles

    Institute of Scientific and Technical Information of China (English)

    Min QING; Zhi-ming YUAN; Pei-Yong Shi

    2009-01-01

    Many flaviviruses are emerging and reemerging pathogens, such as West Nile virus (WNV), dengue virus (DENV), yellow fever virus (YFV), and Japanese encephalitis virus. Serological assay is the dominant method for diagnosis of flavivirus infections in human. Because antibodies generated during flavivirus infections cross-react with other flavivirus members, plaque reduction neutralization test (PRNT) is the only available assay to determine the infecting flavivirus type.Since PRNT requires culturing raw viruses, it must be performed in biosafety level-3 or level-4 containment for many flaviviruses, and takes more than ten days to complete. To overcome these problems, we have developed flavivirus viral-like particles (VLPs) that could be used to replace raw viruses in the neutralization assay. The VLPs were prepared by trans packaging a luciferase-reporting replicon with viral structural proteins. This novel assay involves three simple steps: (ⅰ) VLPs from a panel of flaviviruses are incubated with flavivirus-infected sera at 37℃ for 1 h; (ⅱ)the neutralized VLPs are used to infect Vero cells; and (ⅲ) the infected cells are measured for luciferase activities at 22 h post-infection. The virus type whose VLP is most efficiently neutralized by the serum specimen (as quantified by the luciferase activities) is the etiologic agent. As a proof-of-concept, we show that a WNV-infected mouse serum neutralized the WNV VLP more efficiently and selectively than the DENV and YFV VLPs. Our results demonstrate that the VLP neutralization assay maintains the "gold standard" of the classic PRNT; importantly, it shortens the assay time from >10 days to <1 day, and can be performed in biosafety level-2 facility.

  17. Vaccinia Virus Infections in a Martial Arts Gym

    Centers for Disease Control (CDC) Podcasts

    2011-04-04

    This podcast discusses an outbreak of vaccinia virus in Maryland in 2008. Christine Hughes, a health scientist with the Poxvirus and Rabies Branch at CDC, and co-author of a paper in the April 2011 issue of CDC's journal, discusses vaccinia virus infections in a martial arts gym.  Created: 4/4/2011 by National Center for Emerging Zoonotic and Infectious Diseases (NCEZID).   Date Released: 4/5/2011.

  18. Background review for diagnostic test development for Zika virus infection

    OpenAIRE

    Charrel, Rémi N.; Leparc-Goffart, Isabelle; van der Pas, Suzan; de Lamballerie, Xavier; Koopmans, Marion; Reusken, Chantal

    2016-01-01

    Abstract Objective To review the state of knowledge about diagnostic testing for Zika virus infection and identify areas of research needed to address the current gaps in knowledge. Methods We made a non-systematic review of the published literature about Zika virus and supplemented this with information from commercial diagnostic test kits and personal communications with researchers in European preparedness networks. The review covered current knowledge about the geographical spread, pathog...

  19. Cohabitation reaction-diffusion model for virus focal infections

    Science.gov (United States)

    Amor, Daniel R.; Fort, Joaquim

    2014-12-01

    The propagation of virus infection fronts has been typically modeled using a set of classical (noncohabitation) reaction-diffusion equations for interacting species. However, for some single-species systems it has been recently shown that noncohabitation reaction-diffusion equations may lead to unrealistic descriptions. We argue that previous virus infection models also have this limitation, because they assume that a virion can simultaneously reproduce inside a cell and diffuse away from it. For this reason, we build a several-species cohabitation model that does not have this limitation. Furthermore, we perform a sensitivity analysis for the most relevant parameters of the model, and we compare the predicted infection speed with observed data for two different strains of the T7 virus.

  20. Targeting Viral Proteostasis Limits Influenza Virus, HIV, and Dengue Virus Infection.

    Science.gov (United States)

    Heaton, Nicholas S; Moshkina, Natasha; Fenouil, Romain; Gardner, Thomas J; Aguirre, Sebastian; Shah, Priya S; Zhao, Nan; Manganaro, Lara; Hultquist, Judd F; Noel, Justine; Sachs, David; Sachs, David H; Hamilton, Jennifer; Leon, Paul E; Chawdury, Amit; Tripathi, Shashank; Melegari, Camilla; Campisi, Laura; Hai, Rong; Metreveli, Giorgi; Gamarnik, Andrea V; García-Sastre, Adolfo; Greenbaum, Benjamin; Simon, Viviana; Fernandez-Sesma, Ana; Krogan, Nevan J; Mulder, Lubbertus C F; van Bakel, Harm; Tortorella, Domenico; Taunton, Jack; Palese, Peter; Marazzi, Ivan

    2016-01-19

    Viruses are obligate parasites and thus require the machinery of the host cell to replicate. Inhibition of host factors co-opted during active infection is a strategy hosts use to suppress viral replication and a potential pan-antiviral therapy. To define the cellular proteins and processes required for a virus during infection is thus crucial to understanding the mechanisms of virally induced disease. In this report, we generated fully infectious tagged influenza viruses and used infection-based proteomics to identify pivotal arms of cellular signaling required for influenza virus growth and infectivity. Using mathematical modeling and genetic and pharmacologic approaches, we revealed that modulation of Sec61-mediated cotranslational translocation selectively impaired glycoprotein proteostasis of influenza as well as HIV and dengue viruses and led to inhibition of viral growth and infectivity. Thus, by studying virus-human protein-protein interactions in the context of active replication, we have identified targetable host factors for broad-spectrum antiviral therapies.

  1. Marburg virus infection detected in a common African bat.

    Science.gov (United States)

    Towner, Jonathan S; Pourrut, Xavier; Albariño, César G; Nkogue, Chimène Nze; Bird, Brian H; Grard, Gilda; Ksiazek, Thomas G; Gonzalez, Jean-Paul; Nichol, Stuart T; Leroy, Eric M

    2007-08-22

    Marburg and Ebola viruses can cause large hemorrhagic fever (HF) outbreaks with high case fatality (80-90%) in human and great apes. Identification of the natural reservoir of these viruses is one of the most important topics in this field and a fundamental key to understanding their natural history. Despite the discovery of this virus family almost 40 years ago, the search for the natural reservoir of these lethal pathogens remains an enigma despite numerous ecological studies. Here, we report the discovery of Marburg virus in a common species of fruit bat (Rousettus aegyptiacus) in Gabon as shown by finding virus-specific RNA and IgG antibody in individual bats. These Marburg virus positive bats represent the first naturally infected non-primate animals identified. Furthermore, this is the first report of Marburg virus being present in this area of Africa, thus extending the known range of the virus. These data imply that more areas are at risk for MHF outbreaks than previously realized and correspond well with a recently published report in which three species of fruit bats were demonstrated to be likely reservoirs for Ebola virus.

  2. Marburg virus infection detected in a common African bat.

    Directory of Open Access Journals (Sweden)

    Jonathan S Towner

    Full Text Available Marburg and Ebola viruses can cause large hemorrhagic fever (HF outbreaks with high case fatality (80-90% in human and great apes. Identification of the natural reservoir of these viruses is one of the most important topics in this field and a fundamental key to understanding their natural history. Despite the discovery of this virus family almost 40 years ago, the search for the natural reservoir of these lethal pathogens remains an enigma despite numerous ecological studies. Here, we report the discovery of Marburg virus in a common species of fruit bat (Rousettus aegyptiacus in Gabon as shown by finding virus-specific RNA and IgG antibody in individual bats. These Marburg virus positive bats represent the first naturally infected non-primate animals identified. Furthermore, this is the first report of Marburg virus being present in this area of Africa, thus extending the known range of the virus. These data imply that more areas are at risk for MHF outbreaks than previously realized and correspond well with a recently published report in which three species of fruit bats were demonstrated to be likely reservoirs for Ebola virus.

  3. Detection and diagnosis of rice-infecting viruses

    Directory of Open Access Journals (Sweden)

    Tamaki Uehara Ichiki

    2013-10-01

    Full Text Available Rice-infecting viruses have caused serious damage to rice production in Asian, American, and African countries, where about 30 rice viruses and diseases have been reported. To control these diseases, developing accurate, quick methods to detect and diagnose the viruses in the host plants and any insect vectors of the viruses is very important. Based on an antigen–antibody reaction, serological methods such as latex agglutination reaction (LAR and enzyme-linked immunosorbent assay (ELISA have advanced to detect viral particles or major proteins derived from viruses. They aid in forecasting disease and surveying disease spread and are widely used for virus detection at plant protection stations and research laboratories. From the early 2000s, based on sequence information for the target virus, several other methods such as reverse transcription-polymerase chain reaction (RT-PCR and reverse transcription- loop-mediated isothermal amplification (RT-LAMP have been developed that are sensitive, rapid, and able to differentiate closely related viruses. Recent techniques such as real-time RT-PCR can be used to quantify the pathogen in target samples and monitor population dynamics of a virus, and metagenomic analyses using next-generation sequencing and microarrays show potential for use in the diagnosis of rice diseases.

  4. THE POSSIBLE COLLISIONS IN VIRUS INFECTION IMMUNODIAGNOSTICS AND VACCINATION

    Directory of Open Access Journals (Sweden)

    E. P. Kharchenko

    2016-01-01

    Full Text Available Antibodies (Ab, especially natural, display multiple specificity not only due to intrinsic conformational dynamics. With computational analysis the distribution of identical and homologous peptides has been studied in surface proteins from RNA and DNA viruses of widely distributed infections. It was established that each virus protein shared the fragments homologous to other virus proteins that allowed to propose the existence of the peptide continuum of the protein relationship (PCPR. Possible manifestations of PCPR are multiple reactivity and autoreactivity in Ab and therefore it is not possible to consider the immune methods of virus identification as high reliable because of crossing interactions. The PCPR excludes the existence of 100% specificity in immune tests for virus identification. Immunodiagnostic collisions may occur either in identification of virus itself or identification of Ab to viruses. Also PCPR may be responsible for heterologous immunity and consequently the infection associated with severe pathology. The comparative analysis of peptide relationship of H1N1 influenza virus nucleoprotein and human proteins found out, beyond early described its common motif with human hypocretin receptor 2, peptides homologous to those in melanotonin and glutamate receptors and three ion channels. It allows to propose that the sleep disorder narcolepsy associated with Pandemrix vaccination (an adjuvanted, influenza pandemic vaccine and also with infection by influenza virus during the 2009 A(H1N1 influenza pandemic may be determined not only by Ab to the peptide motif common to influenza nucleoprotein and hypocretin receptor but also Ab to melanotonin and glutamate receptors and ion channels. Decreasing and even avoiding risks of complications from vaccination may be feasible by means of a computer analysis of vaccine proteins for the occurrence of epitopes homologous to the human protein those and particularly by an analysis of Ab profiles

  5. TUBERCULOSIS IN HUMAN IMMUNODEFICIENCY VIRUS-EXPOSED OR VIRUS-INFECTED UNITED-STATES CHILDREN

    NARCIS (Netherlands)

    GUTMAN, LT; MOYE, J; ZIMMER, B; TIAN, C

    1994-01-01

    This study was designed to provide a preliminary assessment of the occurrence of tuberculosis exposure, infection and disease within a national sample of infants and children with human immunodeficiency virus (HIV) exposure or infection, and to determine the prevalence of Mycobacterium tuberculosis

  6. Early Events in Chikungunya Virus Infection-From Virus Cell Binding to Membrane Fusion

    NARCIS (Netherlands)

    van Duijl-Richter, Mareike K. S.; Hoornweg, Tabitha E.; Rodenhuis-Zybert, Izabela A.; Smit, Jolanda M.

    2015-01-01

    Chikungunya virus (CHIKV) is a rapidly emerging mosquito-borne alphavirus causing millions of infections in the tropical and subtropical regions of the world. CHIKV infection often leads to an acute self-limited febrile illness with debilitating myalgia and arthralgia. A potential long-term complica

  7. Argonaute 2 Suppresses Japanese Encephalitis Virus Infection in Aedes aegypti.

    Science.gov (United States)

    Sasaki, Toshinori; Kuwata, Ryusei; Hoshino, Keita; Isawa, Haruhiko; Sawabe, Kyoko; Kobayashi, Mutsuo

    2017-01-24

    There are three main innate immune mechanisms against viruses in mosquitoes. Infection with the flavivirus dengue virus is controlled by RNA interference (RNAi) and the JAK-STAT and Toll signaling pathways. This study showed that another flavivirus, Japanese encephalitis virus (JEV), did not invade the salivary glands of Aedes aegypti and that this may be a result of the innate immune resistance to the virus. Argonaute 2 (Ago2) plays a critical role in the RNAi pathway. To understand the mechanism of JEV resistance, we focused on Ago2 as a possible target of JEV. Here, we show that the expression of MyD88 (a mediator of Toll signaling) and Ago2 mRNAs was induced by JEV in the salivary glands of Ae. aegypti mosquitoes and that Ago2, JAK, and domeless (DOME) mRNAs were induced by JEV in the bodies of Ae. aegypti mosquitoes. Double-stranded (ds) Ago2 RNA enhanced JEV infection, and the virus was detected in salivary glands by immunofluorescence assay. In contrast, MyD88 dsRNA had no effect on JEV infection. These data suggest that Ago2 plays a crucial role in mediating the innate immune response of Ae. aegypti to JEV in a manner similar to that employed by dengue virus.

  8. Possible Association Between Zika Virus Infection and Microcephaly - Brazil, 2015.

    Science.gov (United States)

    Schuler-Faccini, Lavinia; Ribeiro, Erlane M; Feitosa, Ian M L; Horovitz, Dafne D G; Cavalcanti, Denise P; Pessoa, André; Doriqui, Maria Juliana R; Neri, Joao Ivanildo; Neto, Joao Monteiro de Pina; Wanderley, Hector Y C; Cernach, Mirlene; El-Husny, Antonette S; Pone, Marcos V S; Serao, Cassio L C; Sanseverino, Maria Teresa V

    2016-01-29

    In early 2015, an outbreak of Zika virus, a flavivirus transmitted by Aedes mosquitoes, was identified in northeast Brazil, an area where dengue virus was also circulating. By September, reports of an increase in the number of infants born with microcephaly in Zika virus-affected areas began to emerge, and Zika virus RNA was identified in the amniotic fluid of two women whose fetuses had been found to have microcephaly by prenatal ultrasound. The Brazil Ministry of Health (MoH) established a task force to investigate the possible association of microcephaly with Zika virus infection during pregnancy and a registry for incident microcephaly cases (head circumference ≥2 standard deviations [SD] below the mean for sex and gestational age at birth) and pregnancy outcomes among women suspected to have had Zika virus infection during pregnancy. Among a cohort of 35 infants with microcephaly born during August-October 2015 in eight of Brazil's 26 states and reported to the registry, the mothers of all 35 had lived in or visited Zika virus-affected areas during pregnancy, 25 (71%) infants had severe microcephaly (head circumference >3 SD below the mean for sex and gestational age), 17 (49%) had at least one neurologic abnormality, and among 27 infants who had neuroimaging studies, all had abnormalities. Tests for other congenital infections were negative. All infants had a lumbar puncture as part of the evaluation and cerebrospinal fluid (CSF) samples were sent to a reference laboratory in Brazil for Zika virus testing; results are not yet available. Further studies are needed to confirm the association of microcephaly with Zika virus infection during pregnancy and to understand any other adverse pregnancy outcomes associated with Zika virus infection. Pregnant women in Zika virus-affected areas should protect themselves from mosquito bites by using air conditioning, screens, or nets when indoors, wearing long sleeves and pants, using permethrin-treated clothing and gear

  9. A fatal case of chikungunya virus infection with liver involvement.

    Science.gov (United States)

    Chua, H H; Abdul Rashid, K; Law, W C; Hamizah, A; Chem, Y K; Khairul, A H; Chua, K B

    2010-03-01

    Recovery from chikungunya is previously considered universal and mortality due to the virus is rare and unusual. Findings from recent chikungunya outbreaks occurred in Reunion Island and India have since challenged the conventional view on the benign nature of the illness. Malaysia has experienced at least of 4 outbreaks of chikungunya since 1998. In the present on-going large outbreak due to chikungunya virus of Central/East African genotype, a previous healthy sixty six years gentleman without co-morbidity was noted to have severe systemic infection by the virus and involvement of his liver. He subsequently passed away due to cardiovascular collapse after 5 days of illness.

  10. Hepatitis C Virus Infection and Chronic Obstructive Pulmonary Disease

    Directory of Open Access Journals (Sweden)

    Ayten Kadanali

    2009-02-01

    Full Text Available Background and Aims: A growing pile of evidence supports the notion that pulmonary involvement is one of the extrahepatic manifestations of chronic hepatitis C virus (HCV infection. The objective of this study was to determine the prevalence of HCV infection in patients with chronic obstructive pulmonary disease (COPD, and vice versa.Methods: Two cross-sectional studies were performed: 1. A prevalence study of HCV infection among patients with COPD; 2. A prevalence study of COPD among patients with chronic HCV infection. COPD was diagnosed according to ATS/ERS guidelines. The prevalence of HCV infection in COPD group was compared with the result of a previous study which determined the prevalence of HCV infection in general population. Prevalence of COPD in patients with chronic HCV infection was also compared to those with chronic hepatitis B virus (HBV infection.Results: The study included 108 patients with COPD, 68 patients with chronic HCV infection, and 60 patients with chronic HBV infection. HCV infection was observed in 8.3% of patients with COPD, and 1.2% of the control subjects (P= 0.000. The prevalence of COPD among patients with chronic HCV and HBV infection was 17.6%, and 5%, respectively (P=0.03. Comparing COPD-positive and -negative chronic HCV patients for risk factors for COPD revealed that only the mean age was higher in COPD-positive patients (60.8±9.1 years vs. 46.5±11.5 years, P=0.000. In multivariate analysis, age was found to be the only independent predictor of COPD in HCV group.Conclusions: Patients with COPD have increased prevalence of HCV infection, and patients with HCV infection, have increased prevalence of COPD. COPD may be an extrahepatic disease associated with HCV infection.

  11. Extrahepatic manifestations of chronic hepatitis C virus infection.

    Science.gov (United States)

    Cacoub, Patrice; Gragnani, Laura; Comarmond, Cloe; Zignego, Anna Linda

    2014-12-15

    Hepatitis C virus (HCV) infected patients are known to be at risk of developing liver complications i.e. cirrhosis and liver cancer. However, the risks of morbidity and mortality are underestimated because they do not take into account non-liver consequences of chronic hepatitis C virus infection. Numerous extrahepatic manifestations have been reported in up to 74% of patients, from perceived to disabling conditions. The majority of data concern hepatitis C virus-related autoimmune and/or lymphoproliferative disorders, from mixed cryoglobulinaemia vasculitis to frank lymphomas. More recently, other hepatitis C virus-associated disorders have been reported including cardiovascular, renal, metabolic, and central nervous system diseases. This review aims to outline most of the extrahepatic manifestations that are currently being investigated, including some of autoimmune and/or lymphoproliferative nature, and others in which the role of immune mechanisms appears less clear. Beyond the liver, hepatitis C virus chronic infection should be analyzed as a multifaceted systemic disease leading to heavy direct and indirect costs. The accurate consideration of extrahepatic consequences of such a systemic infection significantly increases the weight of its pathological burden. The need for effective viral eradication measures is underlined.

  12. Hepatitis B and C virus co-infections in human immunodeficiency virus positive North Indian patients

    Institute of Scientific and Technical Information of China (English)

    Swati Gupta; Sarman Singh

    2006-01-01

    AIM:To determine the prevalence of hepatitis B and C virus infections in human immunodeficiency virus (HIV) -positive patients at a tertiary care hospital in New Delhi,India.METHODS:Serum samples from 451 HIV positive patients were analyzed for HBsAg and HCV antibodies during three years (Jan 2003-Dec 2005). The control group comprised of apparently healthy bone-marrow and renal donors.RESULTS:The study population comprised essentially of heterosexually transmitted HIV infection. The prevalence rate of HBsAg in this population was 5.3% as compared to 1.4% in apparently healthy donors (P < 0.001).Though prevalence of HCV co-infection (2.43%) was lower than HBV in this group of HIV positive patients,the prevalence was significantly higher (P < 0.05) than controls (0.7%). Triple infection of HIV, HBV and HCV was not detected in any patient.CONCLUSION:Our study shows a significantly high prevalence of hepatitis virus infections in HIV infected patients. Hepatitis viruses in HIV may lead to faster progression to liver cirrhosis and a higher risk of antiretroviral therapy induced hepatotoxicity. Therefore,it would be advisable to detect hepatitis virus coinfections in these patients at the earliest.

  13. A case of Mayaro virus infection imported from French Guiana.

    Science.gov (United States)

    Llagonne-Barets, Marion; Icard, Vinca; Leparc-Goffart, Isabelle; Prat, Christine; Perpoint, Thomas; André, Patrice; Ramière, Christophe

    2016-04-01

    Emergence of arboviruses is a rising problem in several areas in the world. Here we report a case of Mayaro virus infection that was diagnosed in a French citizen presenting a dengue-like syndrome with prolonged arthralgia following a travel in French Guiana. Diagnosis was based on serological testing, a newly developed specific RT-PCR and sequencing. The real incidence of this viral infection among travelers is poorly known but this case is the first reported in a European area where Aedes albopictus mosquitoes are established, which underscores the necessity to determine the vector competence of the European strain of this mosquito species for Mayaro virus.

  14. Multiphasic acute disseminated encephalomyelitis associated with atypical rubella virus infection.

    Science.gov (United States)

    Shinoda, Koji; Asahara, Hideaki; Uehara, Taira; Miyoshi, Katsue; Suzuki, Satoshi O; Iwaki, Toru; Kira, Jun-ichi

    2015-02-01

    We report the first case of an occurrence of multiphasic acute disseminated encephalomyelitis (ADEM) associated with atypical rubella virus infection with no rash and long-term increased titers of serum anti-rubella IgM in a 17-year-old male who had no history of rubella vaccination. He suffered from at least six clinical exacerbations with disseminated hyperintense lesions on FLAIR MR images during the course of 18 months. Repeated methylprednisolone pulse therapy and intravenous immunoglobulin therapy resolved the exacerbations. In patients with multiphasic ADEM of unknown etiology, clinicians should also consider the possibility of preceding infection with rubella virus.

  15. Tahyna virus genetics, infectivity, and immunogenicity in mice and monkeys

    Directory of Open Access Journals (Sweden)

    Whitehead Stephen S

    2011-03-01

    Full Text Available Abstract Background Tahyna virus (TAHV is a human pathogen of the California encephalitis virus (CEV serogroup (Bunyaviridae endemic to Europe, Asia, and Africa. TAHV maintains an enzootic life cycle with several species of mosquito vectors and hares, rabbits, hedgehogs, and rodents serving as small mammal amplifying hosts. Human TAHV infection occurs in summer and early fall with symptoms of fever, headache, malaise, conjunctivitis, pharyngitis, and nausea. TAHV disease can progress to CNS involvement, although unlike related La Crosse virus (LACV, fatalities have not been reported. Human infections are frequent with neutralizing antibodies present in 60-80% of the elderly population in endemic areas. Results In order to determine the genomic sequence of wild-type TAHV, we chose three TAHV isolates collected over a 26-year period from mosquitoes. Here we present the first complete sequence of the TAHV S, M, and L segments. The three TAHV isolates maintained a highly conserved genome with both nucleotide and amino acid sequence identity greater than 99%. In order to determine the extent of genetic relatedness to other members of the CEV serogroup, we compared protein sequences of TAHV with LACV, Snowshoe Hare virus (SSHV, Jamestown Canyon virus (JCV, and Inkoo virus (INKV. By amino acid comparison, TAHV was most similar to SSHV followed by LACV, JCV, and INKV. The sequence of the GN protein is most conserved followed by L, N, GC, NSS, and NSM. In a weanling Swiss Webster mouse model, all three TAHV isolates were uniformly neurovirulent, but only one virus was neuroinvasive. In rhesus monkeys, the virus was highly immunogenic even in the absence of viremia. Cross neutralization studies utilizing monkey immune serum demonstrated that TAHV is antigenically distinct from North American viruses LACV and JCV. Conclusions Here we report the first complete sequence of TAHV and present genetic analysis of new-world viruses, LACV, SSHV, and JCV with old

  16. Review: Occult hepatitis C virus infection: still remains a controversy.

    Science.gov (United States)

    Vidimliski, Pavlina Dzekova; Nikolov, Igor; Geshkovska, Nadica Matevska; Dimovski, Aleksandar; Rostaing, Lionel; Sikole, Aleksandar

    2014-09-01

    Occult hepatitis C virus (HCV) infection is characterized by the presence of HCV RNA in the liver cells or peripheral blood mononuclear cells of the patients whose serum samples test negative for HCV RNA, with or without presence of HCV antibodies. The present study reviews the existing literature on the persistence of occult hepatitis C virus infection, with description of the clinical characteristics and methods for identification of occult hepatitis C. Occult hepatitis C virus infection was detected in patients with abnormal results of liver function tests of unknown origin, with HCV antibodies and HCV RNA negativity in serum, and also in patients with spontaneous or treatment-induced recovery from hepatitis C. The viral replication in the liver cells and/or peripheral blood mononuclear cells was present in all clinical presentations of occult hepatitis C. The peripheral blood mononuclear cells represent an extra-hepatic site of HCV replication. The reason why HCV RNA was not detectable in the serum of patients with occult hepatitis C, could be the low number of circulating viral particles not detectable by the diagnostic tests with low sensitivity. It is uncertain whether occult hepatitis C is a different clinical entity or just a form of chronic hepatitis C virus infection. Data accumulated over the last decade demonstrated that an effective approach to the diagnosis of HCV infection would be the implementation of more sensitive HCV RNA diagnostic assays, and also, examination of the presence of viral particles in the cells of the immune system.

  17. Adaptive immune response during hepatitis C virus infection.

    Science.gov (United States)

    Larrubia, Juan Ramón; Moreno-Cubero, Elia; Lokhande, Megha Uttam; García-Garzón, Silvia; Lázaro, Alicia; Miquel, Joaquín; Perna, Cristian; Sanz-de-Villalobos, Eduardo

    2014-04-07

    Hepatitis C virus (HCV) infection affects about 170 million people worldwide and it is a major cause of liver cirrhosis and hepatocellular carcinoma. HCV is a hepatotropic non-cytopathic virus able to persist in a great percentage of infected hosts due to its ability to escape from the immune control. Liver damage and disease progression during HCV infection are driven by both viral and host factors. Specifically, adaptive immune response carries out an essential task in controlling non-cytopathic viruses because of its ability to recognize infected cells and to destroy them by cytopathic mechanisms and to eliminate the virus by non-cytolytic machinery. HCV is able to impair this response by several means such as developing escape mutations in neutralizing antibodies and in T cell receptor viral epitope recognition sites and inducing HCV-specific cytotoxic T cell anergy and deletion. To impair HCV-specific T cell reactivity, HCV affects effector T cell regulation by modulating T helper and Treg response and by impairing the balance between positive and negative co-stimulatory molecules and between pro- and anti-apoptotic proteins. In this review, the role of adaptive immune response in controlling HCV infection and the HCV mechanisms to evade this response are reviewed.

  18. Tacaribe virus but not junin virus infection induces cytokine release from primary human monocytes and macrophages.

    Directory of Open Access Journals (Sweden)

    Allison Groseth

    Full Text Available The mechanisms underlying the development of disease during arenavirus infection are poorly understood. However, common to all hemorrhagic fever diseases is the involvement of macrophages as primary target cells, suggesting that the immune response in these cells may be of paramount importance during infection. Thus, in order to identify features of the immune response that contribute to arenavirus pathogenesis, we have examined the growth kinetics and cytokine profiles of two closely related New World arenaviruses, the apathogenic Tacaribe virus (TCRV and the hemorrhagic fever-causing Junin virus (JUNV, in primary human monocytes and macrophages. Both viruses grew robustly in VeroE6 cells; however, TCRV titres were decreased by approximately 10 fold compared to JUNV in both monocytes and macrophages. Infection of both monocytes and macrophages with TCRV also resulted in the release of high levels of IL-6, IL-10 and TNF-α, while levels of IFN-α, IFN-β and IL-12 were not affected. However, we could show that the presence of these cytokines had no direct effect on growth of either TCRV of JUNV in macrophages. Further analysis also showed that while the production of IL-6 and IL-10 are dependent on viral replication, production of TNF-α also occurs after exposure to UV-inactivated TCRV particles and is thus independent of productive virus infection. Surprisingly, JUNV infection did not have an effect on any of the cytokines examined indicating that, in contrast to other viral hemorrhagic fever viruses, macrophage-derived cytokine production is unlikely to play an active role in contributing to the cytokine dysregulation observed in JUNV infected patients. Rather, these results suggest that an early, controlled immune response by infected macrophages may be critical for the successful control of infection of apathogenic viruses and prevention of subsequent disease, including systemic cytokine dysregulation.

  19. Schmallenberg virus experimental infection of sheep

    DEFF Research Database (Denmark)

    Wernike, Kerstin; Hoffmann, Bernd; Bréard, Emmanuel

    2013-01-01

    production and diarrhoea for a few days. However, the knowledge about clinical signs and pathogenesis in adult sheep is limited.In the present study, adult sheep of European domestic breeds were inoculated with SBV either as cell culture grown virus or as virus with no history of passage in cell cultures....... Various experimental set-ups were used. Sampling included blood collection at different time points during the experimental period and selected organ material at autopsy.Data from this study showed, that the RNAemic period in sheep was as short as reported for cattle; viral genome was detectable for about...... 3–5 days by real-time RT-PCR. In total, 13 out of 30 inoculated sheep became RNAemic, with the highest viral load in animals inoculated with virus from low cell culture passaged or the animal passaged material. Contact animals remained negative throughout the study. One RNAemic sheep showed...

  20. Aedes aegypti D7 Saliva Protein Inhibits Dengue Virus Infection

    Science.gov (United States)

    Conway, Michael J.; Londono-Renteria, Berlin; Troupin, Andrea; Watson, Alan M.; Klimstra, William B.; Fikrig, Erol; Colpitts, Tonya M.

    2016-01-01

    Aedes aegypti is the primary vector of several medically relevant arboviruses including dengue virus (DENV) types 1–4. Ae. aegypti transmits DENV by inoculating virus-infected saliva into host skin during probing and feeding. Ae. aegypti saliva contains over one hundred unique proteins and these proteins have diverse functions, including facilitating blood feeding. Previously, we showed that Ae. aegypti salivary gland extracts (SGEs) enhanced dissemination of DENV to draining lymph nodes. In contrast, HPLC-fractionation revealed that some SGE components inhibited infection. Here, we show that D7 proteins are enriched in HPLC fractions that are inhibitory to DENV infection, and that recombinant D7 protein can inhibit DENV infection in vitro and in vivo. Further, binding assays indicate that D7 protein can directly interact with DENV virions and recombinant DENV envelope protein. These data reveal a novel role for D7 proteins, which inhibits arbovirus transmission to vertebrates through a direct interaction with virions. PMID:27632170

  1. Oral conditions associated with Hepatitis C virus infection

    Directory of Open Access Journals (Sweden)

    Seyed-Moayed Alavian

    2013-01-01

    Full Text Available Hepatitis C virus (HCV infection in more than 170 million chronically infected patients with no developed preventive vaccine is a globally important issue. In addition to expected hepatic manifestations, a number of extrahepatic manifestations, such as mixed cryoglobulinemia, glomerulonephritis, polyarteritis nodosa, rashes, renal disease, neuropathy, and lymphoma, have been reported following HCV infection, which are believed to be influenced by the virus or the host immune response. HCV combination therapy with pegylated interferon and ribavirin might be associated with side effects as well. The association of HCV with special oral conditions has also been reported recurrently; the mechanism of most of which remains unclear. This article reviews the association of HCV infection with some of the oral conditions such as oral health, Sjogren′s syndrome, lichen planus and oral cancer.

  2. Phosphorylation of the viral coat protein regulates RNA virus infection

    Directory of Open Access Journals (Sweden)

    Hoover HS

    2016-11-01

    Full Text Available Haley S Hoover, C Cheng Kao Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, IN, USA Abstract: Coat proteins (CPs are the most abundant protein produced during a viral infection. CPs have been shown to regulate the infection processes of RNA viruses, including RNA replication and gene expression. The numerous activities of the CP in infection are likely to require regulation, possibly through posttranslational modifications. Protein posttranslational modifications are involved in signal transduction, expanding and regulating protein function, and responding to changes in the environment. Accumulating evidence suggests that phosphorylation of viral CPs is involved in the regulation of the viral infection process from enabling virion disassembly to regulation of viral protein synthesis and replication. CP phosphorylation also affects viral trafficking and virion assembly. This review focuses on the regulatory roles that phosphorylation of CPs has in the life cycle of viruses with RNA genomes. Keywords: viral capsid protein, posttranslational modification, phosphorylation, protein–RNA interaction

  3. Transcriptome analysis of feline infectious peritonitis virus infection.

    Science.gov (United States)

    Mehrbod, Parvaneh; Harun, Mohammad Syamsul Reza; Shuid, Ahmad Naqib; Omar, Abdul Rahman

    2015-01-01

    Feline infectious peritonitis (FIP) is a lethal systemic disease caused by FIP virus (FIPV). There are no effective vaccines or treatment available, and the virus virulence determinants and pathogenesis are not fully understood. Here, we describe the sequencing of RNA extracted from Crandell Rees Feline Kidney (CRFK) cells infected with FIPV using the Illumina next-generation sequencing approach. Bioinformatics analysis, based on Felis catus 2X annotated shotgun reference genome, using CLC bio Genome Workbench is used to map both control and infected cells. Kal's Z test statistical analysis is used to analyze the differentially expressed genes from the infected CRFK cells. In addition, RT-qPCR analysis is used for further transcriptional profiling of selected genes in infected CRFK cells and Peripheral Blood Mononuclear Cells (PBMCs) from healthy and FIP-diagnosed cats.

  4. Detection of Zika Virus Infection in Thailand, 2012–2014

    OpenAIRE

    Buathong, Rome; Hermann, Laura; Thaisomboonsuk, Butsaya; Rutvisuttinunt, Wiriya; Klungthong, Chonticha; Chinnawirotpisan, Piyawan; Manasatienkij, Wudtichai; Nisalak, Ananda; Fernandez, Stefan; Yoon, In-Kyu; Akrasewi, Passakorn; Plipat, Tanarak

    2015-01-01

    Zika virus (ZIKV) is an emerging mosquito-borne pathogen with reported cases in Africa, Asia, and large outbreaks in the Pacific. No autochthonous ZIKV infections have been confirmed in Thailand. However, there have been several cases reported in travelers returning from Thailand. Here we report seven cases of acute ZIKV infection in Thai residents across the country confirmed by molecular or serological testing including sequence data. These endemic cases, combined with previous reports in t...

  5. Transmission of hepatitis C virus infection to tree shrews

    OpenAIRE

    Xie, Z.C. (Zhi-Chun); Riezu-Boj, J.I. (José Ignacio); Lasarte, J.J. (Juan José); GUILLEN, J; Su, J. H.; Civeira, M P; Prieto, J.

    1998-01-01

    Although hepatitis C virus (HCV) infection can be reproduced in chimpanzees, these animals are rare and expensive. Tree shrews (tupaias) are small animals, closely related to primates, which adapt easily to a laboratory environment. In this work we have investigated the susceptibility of Tupaia belangeri chinensis to HCV infection. Tupaias caught in the wild in Yunnan (China) were inoculated in China with HCV genotype 1b (study A) and in Spain with a mixture of genotypes 1b, 1a, and 3 (study ...

  6. Extrahepatic manifestations of chronic hepatitis C virus infection

    OpenAIRE

    Cacoub, Patrice; Comarmond, Cloe; Domont, Fanny; Savey, Léa; Desbois, Anne claire; Saadoun, David

    2016-01-01

    International audience; During hepatitis C virus (HCV) chronic infection, extrahepatic manifestations are frequent and polymorphous. This article reports on a large cohort of patients with HCV-related autoimmune or lymphoproliferative disorders, from mixed cryoglobulinemia vasculitis to frank lymphomas. The relationship between HCV infection and such immune-related diseases has been formally demonstrated by epidemiological, clinical, immunological and pathological data, and results of therape...

  7. Recent advances in understanding and diagnosing hepatitis B virus infection

    OpenAIRE

    Fourati, Slim; Pawlotsky, Jean-Michel

    2016-01-01

    Hepatitis B virus (HBV) infects approximately 240 million individuals worldwide. Recent advances in the virology, immunopathogenesis, and diagnosis of HBV infection are summarized in this review article. The identification of a hepatocyte-specific cellular receptor for HBV, the sodium taurocholate co-transporting polypeptide (NTCP), made it possible to develop reliable cell culture systems and better understand the early steps of the viral lifecycle. Viral and host factors involved in covalen...

  8. The Effects of High Temperature on Infection by Potato virus Y, Potato virus A, and Potato leafroll virus

    Science.gov (United States)

    Chung, Bong Nam; Canto, Tomas; Tenllado, Francisco; Choi, Kyung San; Joa, Jae Ho; Ahn, Jeong Joon; Kim, Chun Hwan; Do, Ki Seck

    2016-01-01

    We examined the effects of temperature on acquisition of Potato virus Y-O (PVY-O), Potato virus A (PVA), and Potato leafroll virus (PLRV) by Myzus persicae by performing transmission tests with aphids that acquired each virus at different temperatures. Infection by PVY-O/PVA and PLRV increased with increasing plant temperature in Nicotiana benthamiana and Physalis floridana, respectively, after being transmitted by aphids that acquired them within a temperature range of 10–20°C. However, infection rates subsequently decreased. Direct qRT-PCR of RNA extracted from a single aphid showed that PLRV infection increased in the 10–20°C range, but this trend also declined shortly thereafter. We examined the effect of temperature on establishment of virus infection. The greatest number of plants became infected when N. benthamiana was held at 20°C after inoculation with PVY-O or PVA. The largest number of P. floridana plants became infected with PLRV when the plants were maintained at 25°C. PLRV levels were highest in P. floridana kept at 20–25°C. These results indicate that the optimum temperatures for proliferation of PVY-O/PVA and PLRV differed. Western blot analysis showed that accumulations of PVY-O and PVA coat proteins (CPs) were lower at 10°C or 15°C than at 20°C during early infection. However, accumulation increased over time. At 25°C or 30°C, the CPs of both viruses accumulated during early infection but disappeared as time passed. Our results suggest that symptom attenuation and reduction of PVY-O and PVA CP accumulation at higher temperatures appear to be attributable to increased RNA silencing. PMID:27493607

  9. Immunology and Pathology of Arena Virus Infections.

    Science.gov (United States)

    1992-04-15

    and incubated in FITC goat anti-guinea pig immunoglobulin G ( Kierkegaard - Perry) for 30 mins. After washing, slides or cover slips were counterstained...PV (adPV)-infected or strain 3739-infected Vero cell antigen dots and FITC goat anti-guinea pig IgG (H+L) ( Kierkegaard - Perry). Test sera were

  10. Zoonotic aspects of arenavirus infections.

    Science.gov (United States)

    Charrel, R N; de Lamballerie, X

    2010-01-27

    To date, the International Committee for Taxonomy of Viruses recognizes that the family Arenaviridae contains a unique genus Arenavirus that includes 22 viral species. There are nine additional arenaviruses that either have been discovered recently, or which taxonomic status remains pending. Arenaviruses have been classified according to their antigenic properties into two groups, the Lassa-Lymphocytic choriomeningitis (LCM) serocomplex and the Tacaribe serocomplex which has been further divided into four evolutionary lineages. Each arenavirus is more or less tightly associated with a mammal host. The distribution of the host dictates the distribution of the virus. Humans may become infected by arenaviruses through direct contact with infected rodents, including bites, or through inhalation of infectious rodent excreta and secreta. Lassa, Junin, Machupo, Guanarito, and Sabia viruses are known to cause a severe hemorrhagic fever, in western Africa, Argentina, Bolivia, Venezuela, and Brazil, respectively. Infection by LCM virus can result in acute central nervous system disease, congenital malformations, and infection in organ transplantation recipients. Detection of arenaviruses in their animal host can be achieved by virus isolation, and has recently taken advantage of PCR-based techniques. The approach based on consensus degenerate primers has shown efficient for both detection of known arenaviruses, and discovery of new arenaviruses.

  11. Simian varicella virus infection of Chinese rhesus macaques produces ganglionic infection in the absence of rash

    NARCIS (Netherlands)

    W.J.D. Ouwendijk (Werner ); R. Mahalingam (Ravi); V. Traina-Dorge (Vicki); G. van Amerongen (Geert); M. Wellish (Mary); A.D.M.E. Osterhaus (Albert); D. Gilden (Don); G.M.G.M. Verjans (George)

    2012-01-01

    textabstractVaricella-zoster virus (VZV) causes varicella (chickenpox), becomes latent in ganglia along the entire neuraxis, and may reactivate to cause herpes zoster (shingles). VZV may infect ganglia via retrograde axonal transport from infected skin or through hematogenous spread. Simian varicell

  12. The role of IKKβ in Venezuelan equine encephalitis virus infection.

    Directory of Open Access Journals (Sweden)

    Moushimi Amaya

    Full Text Available Venezuelan equine encephalitis virus (VEEV belongs to the genus Alphavirus, family Togaviridae. VEEV infection is characterized by extensive inflammation and studies from other laboratories implicated an involvement of the NF-κB cascade in the in vivo pathology. Initial studies indicated that at early time points of VEEV infection, the NF-κB complex was activated in cells infected with the TC-83 strain of VEEV. One upstream kinase that contributes to the phosphorylation of p65 is the IKKβ component of the IKK complex. Our previous studies with Rift valley fever virus, which exhibited early activation of the NF-κB cascade in infected cells, had indicated that the IKKβ component underwent macromolecular reorganization to form a novel low molecular weight form unique to infected cells. This prompted us to investigate if the IKK complex undergoes a comparable macromolecular reorganization in VEEV infection. Size-fractionated VEEV infected cell extracts indicated a macromolecular reorganization of IKKβ in VEEV infected cells that resulted in formation of lower molecular weight complexes. Well-documented inhibitors of IKKβ function, BAY-11-7082, BAY-11-7085 and IKK2 compound IV, were employed to determine whether IKKβ function was required for the production of infectious progeny virus. A decrease in infectious viral particles and viral RNA copies was observed with inhibitor treatment in the attenuated and virulent strains of VEEV infection. In order to further validate the requirement of IKKβ for VEEV replication, we over-expressed IKKβ in cells and observed an increase in viral titers. In contrast, studies carried out using IKKβ(-/- cells demonstrated a decrease in VEEV replication. In vivo studies demonstrated that inhibitor treatment of TC-83 infected mice increased their survival. Finally, proteomics studies have revealed that IKKβ may interact with the viral protein nsP3. In conclusion, our studies have revealed that the host IKK

  13. Hepatitis C virus infection management in 2012.

    NARCIS (Netherlands)

    Gulick, J.J. van; Lamers, M.H.; Drenth, J.P.H.

    2012-01-01

    Hepatitis C virus (HCV) is the most common infectious cause of chronic liver disease in Europe. With the introduction of interferon based therapy in combination with ribavirin treatment of chronic HCV has become feasible. This therapy has become the standard of care for patients with HCV and dependi

  14. ROLE OF THE SEROLOGIC TEST FOR DENGUE VIRUS INFECTION

    Directory of Open Access Journals (Sweden)

    Ni Luh Sinta Purnama Dewi

    2013-07-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE Dengue virus infection is infection disease cause by dengue virus. Dengue virus infection can cause a broad spectrum disease such as : dengue fever (DF, dengue hemorrhagic fever (DHF, and dengue shock syndrome (DSS. Currently dengue virus ranks eighth as a cause of illness in the State of South-East Asia and Western Pacific. Epidemic dengue hemorrhagic fever (DHF occur each year in Indonesia with a tendency incident and the affected area is increasing. Laboratory tests can be done to detect the dengue virus infection: a complete blood count and serology. Of serology test, positive IgM antibody showed that patients had a primary infection, whereas patients with secondary infections showed positive IgG antibodies, usually accompanied by antibody IgM positive. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

  15. Neutralizing Antibodies and Pathogenesis of Hepatitis C Virus Infection

    Directory of Open Access Journals (Sweden)

    Françoise Stoll-Keller

    2012-10-01

    Full Text Available Hepatitis C virus (HCV infection is a major cause of chronic liver disease worldwide. The interplay between the virus and host innate and adaptive immune responses determines the outcome of infection. There is increasing evidence that host neutralizing responses play a relevant role in the resulting pathogenesis. Furthermore, viral evasion from host neutralizing antibodies has been revealed to be an important contributor in leading both to viral persistence in acute liver graft infection following liver transplantation, and to chronic viral infection. The development of novel model systems to study HCV entry and neutralization has allowed a detailed understanding of the molecular mechanisms of virus-host interactions during antibody-mediated neutralization. The understanding of these mechanisms will ultimately contribute to the development of novel antiviral preventive strategies for liver graft infection and an urgently needed vaccine. This review summarizes recent concepts of the role of neutralizing antibodies in viral clearance and protection, and highlights consequences of viral escape from neutralizing antibodies in the pathogenesis of HCV infection.

  16. Mayaro virus infection cycle relies on casein kinase 2 activity.

    Science.gov (United States)

    Barroso, Madalena M S; Lima, Carla S; Silva-Neto, Mário A C; Da Poian, Andrea T

    2002-09-06

    Replication of Mayaro virus in Vero cells induces dramatic cytopathic effects and cell death. In this study, we have evaluated the role of casein kinase 2 (CK2) during Mayaro virus infection cycle. We found that CK2 was activated during the initial stages of infection ( approximately 36% after 4h). This activation was further confirmed when the enzyme was partially purified from the cellular lysate either by Mono Q 5/5Hr column or heparin-agarose column. Using this later column, we found that the elution profile of CK2 activity from infected cells was different from that obtained for control cell enzyme, suggesting a structural modification of CK2 after infection. Treatment of infected cells with a cell-permeable inhibitor of CK2, dichloro-1-(beta-D-ribofuranosyl)benzimidazole (DRB), abolished the cytopathic effect in a dose-dependent manner. Together this set of data demonstrates for the first time that CK2 activity in host cells is required in Mayaro virus infection cycle.

  17. Host sphingomyelin increases West Nile virus infection in vivo.

    Science.gov (United States)

    Martín-Acebes, Miguel A; Gabandé-Rodríguez, Enrique; García-Cabrero, Ana M; Sánchez, Marina P; Ledesma, María Dolores; Sobrino, Francisco; Saiz, Juan-Carlos

    2016-03-01

    Flaviviruses, such as the dengue virus and the West Nile virus (WNV), are arthropod-borne viruses that represent a global health problem. The flavivirus lifecycle is intimately connected to cellular lipids. Among the lipids co-opted by flaviviruses, we have focused on SM, an important component of cellular membranes particularly enriched in the nervous system. After infection with the neurotropic WNV, mice deficient in acid sphingomyelinase (ASM), which accumulate high levels of SM in their tissues, displayed exacerbated infection. In addition, WNV multiplication was enhanced in cells from human patients with Niemann-Pick type A, a disease caused by a deficiency of ASM activity resulting in SM accumulation. Furthermore, the addition of SM to cultured cells also increased WNV infection, whereas treatment with pharmacological inhibitors of SM synthesis reduced WNV infection. Confocal microscopy analyses confirmed the association of SM with viral replication sites within infected cells. Our results unveil that SM metabolism regulates flavivirus infection in vivo and propose SM as a suitable target for antiviral design against WNV.

  18. Alteration of cell cycle progression by Sindbis virus infection

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Ruirong; Saito, Kengo [Department of Molecular Virology, Graduate School of Medicine, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chiba 260-8670 (Japan); Isegawa, Naohisa [Laboratory Animal Center, Graduate School of Medicine, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chiba 260-8670 (Japan); Shirasawa, Hiroshi, E-mail: sirasawa@faculty.chiba-u.jp [Department of Molecular Virology, Graduate School of Medicine, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chiba 260-8670 (Japan)

    2015-07-10

    We examined the impact of Sindbis virus (SINV) infection on cell cycle progression in a cancer cell line, HeLa, and a non-cancerous cell line, Vero. Cell cycle analyses showed that SINV infection is able to alter the cell cycle progression in both HeLa and Vero cells, but differently, especially during the early stage of infection. SINV infection affected the expression of several cell cycle regulators (CDK4, CDK6, cyclin E, p21, cyclin A and cyclin B) in HeLa cells and caused HeLa cells to accumulate in S phase during the early stage of infection. Monitoring SINV replication in HeLa and Vero cells expressing cell cycle indicators revealed that SINV which infected HeLa cells during G{sub 1} phase preferred to proliferate during S/G{sub 2} phase, and the average time interval for viral replication was significantly shorter in both HeLa and Vero cells infected during G{sub 1} phase than in cells infected during S/G{sub 2} phase. - Highlights: • SINV infection was able to alter the cell cycle progression of infected cancer cells. • SINV infection can affect the expression of cell cycle regulators. • SINV infection exhibited a preference for the timing of viral replication among the cell cycle phases.

  19. Infection of brain-derived cells with the human immunodeficiency virus.

    Science.gov (United States)

    Chiodi, F; Fuerstenberg, S; Gidlund, M; Asjö, B; Fenyö, E M

    1987-01-01

    A malignant glioma cell line was infected with the human T-lymphotropic virus type IIIB isolate of the human immunodeficiency virus. Infection appeared to be latent rather than productive. Through contact with monocytic or lymphoid cells, the virus present in the glioma cells could be transmitted and gave rise to a fully productive infection. Images PMID:3644020

  20. Host DNA damage response facilitates African swine fever virus infection.

    Science.gov (United States)

    Simões, Margarida; Martins, Carlos; Ferreira, Fernando

    2013-07-26

    Studies with different viral infection models on virus interactions with the host cell nucleus have opened new perspectives on our understanding of the molecular basis of these interactions in African swine fever virus (ASFV) infection. The present study aims to characterize the host DNA damage response (DDR) occurring upon in vitro infection with the ASFV-Ba71V isolate. We evaluated protein levels during ASFV time-course infection, of several signalling cascade factors belonging to DDR pathways involved in double strand break repair - Ataxia Telangiectasia Mutated (ATM), ATM-Rad 3 related (ATR) and DNA dependent protein kinase catalytic subunit (DNA-PKcs). DDR inhibitory trials using caffeine and wortmannin and ATR inducible-expression cell lines were used to confirm specific pathway activation during viral infection. Our results show that ASFV specifically elicits ATR-mediated pathway activation from the early phase of infection with increased levels of H2AX, RPA32, p53, ATR and Chk1 phosphorylated forms. Viral p72 synthesis was abrogated by ATR kinase inhibitors and also in ATR-kd cells. Furthermore, a reduction of viral progeny was identified in these cells when compared to the outcome of infection in ATR-wt. Overall, our results strongly suggest that the ATR pathway plays an essential role for successful ASFV infection of host cells.

  1. Prevalence of hepatitis virus infections in Albanian refugees.

    Science.gov (United States)

    Santantonio, T; Lo Caputo, S; Germinario, C; Squarcione, S; Greco, D; Laddago, V; Pastore, G

    1993-09-01

    A sample of 393 Albanian refugees, including both children and adults, was tested for serological HAV, HBV, HDV and HCV markers. A high prevalence of infection with both the hepatitis A and B viruses was found, while HDV and HCV infections were uncommon. The overall prevalence of anti-HAV was 96%; it was very high in children 0-10 years, suggesting that HAV infection is largely acquired during childhood and that poor ambiental conditions influence the spreading of this viral infection. One or more serological markers of HBV infection were found in 295 Albanians (75%), confirming the endemic nature of this virus in the Albanian community. The overall prevalence of HBsAg was 19%, and the carrier rate was higher in males than in females. The high HBsAg prevalence among children suggests that HBV infection is usually acquired in early childhood. The serological data obtained in the Albanian sample examined clearly indicate the urgent need for measures to reduce the incidence of HAV and HBV infections and to avoid the further spread of HDV and HCV infections. Finally, the high prevalence of type B hepatitis indicates the necessity of vaccination against HBV for all risk groups and for all children at birth.

  2. Evidence of Apis cerana Sacbrood virus Infection in Apis mellifera

    Science.gov (United States)

    Gong, Hong-Ri; Chen, Xiu-Xian; Chen, Yan Ping; Hu, Fu-Liang; Zhang, Jiang-Lin; Lin, Zhe-Guang; Yu, Ji-Wei

    2016-01-01

    Sacbrood virus (SBV) is one of the most destructive viruses in the Asian honeybee Apis cerana but is much less destructive in Apis mellifera. In previous studies, SBV isolates infecting A. cerana (AcSBV) and SBV isolates infecting A. mellifera (AmSBV) were identified as different serotypes, suggesting a species barrier in SBV infection. In order to investigate this species isolation, we examined the presence of SBV infection in 318 A. mellifera colonies and 64 A. cerana colonies, and we identified the genotypes of SBV isolates. We also performed artificial infection experiments under both laboratory and field conditions. The results showed that 38 A. mellifera colonies and 37 A. cerana colonies were positive for SBV infection. Phylogenetic analysis based on RNA-dependent RNA polymerase (RdRp) gene sequences indicated that A. cerana isolates and most A. mellifera isolates formed two distinct clades but two strains isolated from A. mellifera were clustered with the A. cerana isolates. In the artificial-infection experiments, AcSBV negative-strand RNA could be detected in both adult bees and larvae of A. mellifera, although there were no obvious signs of the disease, demonstrating the replication of AcSBV in A. mellifera. Our results suggest that AcSBV is able to infect A. mellifera colonies with low prevalence (0.63% in this study) and pathogenicity. This work will help explain the different susceptibilities of A. cerana and A. mellifera to sacbrood disease and is potentially useful for guiding beekeeping practices. PMID:26801569

  3. Hepatitus B virus infection : factors influencing the outcome

    NARCIS (Netherlands)

    J. van Hattum (Jan)

    1986-01-01

    textabstractThis study was designed to find correlations between the various courses of disease after hepatitis B virus (HBV) infection and factors that could conceivably have influenced the course of disease. The aim of the study was to find correlations between parameters of viral replication and

  4. Transgenic tomato hybrids resistant to tomato spotted wilt virus infection.

    NARCIS (Netherlands)

    Haan, de P.; Ultzen, T.; Prins, M.; Gielen, J.; Goldbach, R.; Grinsven, van M.

    1996-01-01

    Tomato spotted wilt virus (TSWV) infections cause significant economic losses in the commercial culture of tomato (Lycopersicon esculentum). Culture practices have only been marginally effective in controlling TSWV. The ultimate way to minimize losses caused by TSWV is resistant varieties. These can

  5. Therapeutic vaccination against chronic hepatitis C virus infection

    NARCIS (Netherlands)

    Ip, Peng Peng; Nijman, Hans W.; Wilschut, Jan; Daemen, Toos

    2012-01-01

    Approximately 170 million people worldwide are chronic carriers of Hepatitis C virus (HCV). To date, there is no prophylactic vaccine available against HCV. The standard-of-care therapy for HCV infection involves a combination of pegylated interferon-α and ribavirin. This therapy, which is commonly

  6. Vaccination against feline immunodeficiency virus using fixed infected cells

    NARCIS (Netherlands)

    Horzinek, M.C.; Verschoor, E.J.; Vliet, A.L.W. van; Egberink, H.F.; Hesselink, W.; Alphen, W.E. van; Joosten, I.; Boog, C.J.P.; Ronde, A. de

    1995-01-01

    Crandell feline kidney cells and feline thymocytes, either feline immunodeficiency virus (FIV) infected or uninfected, were fixed with paraformaldehyde and used to vaccinate cats. The cells were mixed with a 30:70 water/mineral oil emulsion containing 250 mu g ml−1 N-acetyl-d-glucosaminyl-beta-(1 4)

  7. Human skin Langerhans cells are targets of dengue virus infection

    NARCIS (Netherlands)

    Wu, SJL; Grouard-Vogel, G; Mascola, [No Value; Brachtel, E; Putvatana, R; Louder, MK; Filgueira, L; Marovich, MA; Wong, HK; Blauvelt, A; Murphy, GS; Robb, ML; Innes, BL; Birx, DL; Hayes, CG; Frankel, SS

    2000-01-01

    Dengue virus (DV), an arthropod-borne flavivirus, causes a febrile illness for which there is no antiviral treatment and no vaccine(1,2). Macrophages are important in dengue pathogenesis; however, the initial target cell for DV infection remains unknown. As DV is introduced into human skin by mosqui

  8. Breaking barriers : Early events in chikungunya and dengue virus infections

    NARCIS (Netherlands)

    Hoornweg, Tabitha Elina

    2016-01-01

    Breaking Barriers – early events in chikungunya and dengue virus infections Chikungunya en dengue zijn twee door muggen overdraagbare virussen die voornamelijk voorkomen in (sub)tropische gebieden. Sinds 2006 verspreidt het chikungunyavirus zich in een razend tempo over de wereld. Miljoenen mensen r

  9. Epidemiology and Prevention of Hepatitis B Virus Infection

    Directory of Open Access Journals (Sweden)

    2005-01-01

    Full Text Available Hepatitis B is one of the most common infectious diseases globally. It has been estimated that there are 350 million chronic hepatitis B virus (HBV carriers worldwide. The prevalence of chronic HBV infection varies geographically, from high (>8%, intermediate (2-7% to low (

  10. Inhibition of Mayaro virus infection by bovine lactoferrin.

    Science.gov (United States)

    Carvalho, Carlos A M; Sousa, Ivanildo P; Silva, Jerson L; Oliveira, Andréa C; Gonçalves, Rafael B; Gomes, Andre M O

    2014-03-01

    Mayaro virus (MAYV) is an arbovirus linked to several sporadic outbreaks of a highly debilitating febrile illness in many regions of South America. MAYV is on the verge of urbanization from the Amazon region and no effective antiviral intervention is available against human infections. Our aim was to investigate whether bovine lactoferrin (bLf), an iron-binding glycoprotein, could hinder MAYV infection. We show that bLf promotes a strong inhibition of virus infection with no cytotoxic effects. Monitoring the effect of bLf on different stages of infection, we observed that virus entry into the cell is the heavily compromised event. Moreover, we found that binding of bLf to the cell is highly dependent on the sulfation of glycosaminoglycans, suggesting that bLf impairs virus entry by blocking these molecules. Our findings highlight the antiviral potential of bLf and reveal an effective strategy against one of the major emerging human pathogens in the neotropics.

  11. Caesarean Section and Hospitalization for Respiratory Syncytial Virus Infection

    DEFF Research Database (Denmark)

    Kristensen, Kim; Fisker, Niels; Haerskjold, Ann

    2015-01-01

    BACKGROUND AND OBJECTIVE:: Hospitalization for respiratory syncytial virus (RSV) infection and asthma share common determinants, and meta-analyses indicate that children delivered by caesarean section (CS) are at increased risk of asthma. We aimed to investigate whether birth by CS is associated ...

  12. Progression of experimental chronic Aleutian mink disease virus infection

    DEFF Research Database (Denmark)

    Jensen, Trine Hammer; Chriél, Mariann; Hansen, Mette Sif

    2016-01-01

    Aleutian mink disease virus (AMDV) is found world-wide and has a major impact on mink health and welfare by decreasing reproduction and fur quality. In the majority of mink, the infection is subclinical and the diagnosis must be confirmed by serology or polymerase chain reaction (PCR). Increased ...

  13. Regulatory T Cells in Chronic Hepatitis B Virus Infection

    NARCIS (Netherlands)

    J.N. Stoop (Jeroen Nicolaas)

    2007-01-01

    textabstractWorldwide 400 million people suffer from chronic hepatitis B virus (HBV) infection and approximately 1 million people die annually from HBV-related disease. To clear HBV, an effective immune response, in which several cell types and cytokines play a role, is important. It is known that p

  14. Neutralizing antibodies in cats infected with feline immunodeficiency virus.

    NARCIS (Netherlands)

    F. Tozzini; D. Matteucci; P. Bandecchi; F. Baldinotti; C.H.J. Siebelink (Kees); A.D.M.E. Osterhaus (Albert); M. Bendinelli

    1993-01-01

    textabstractSera from cats experimentally infected with five isolates of feline immunodeficiency virus (FIV) from various geographical regions and from FIV enzyme-linked immunosorbent assay-seropositive field cats from four European countries neutralized the Petaluma strain of FIV (FIV-P), originall

  15. Role of antibodies in controlling dengue virus infection

    NARCIS (Netherlands)

    van der Schaar, Hilde M.; Wilschut, Jan C.; Smit, Jolanda M.

    2009-01-01

    The incidence and disease burden of arthropod-borne flavivirus infections have dramatically increased during the last decades due to major societal and economic changes, including massive urbanization, lack of vector control, travel, and international trade. Specifically, in the case of dengue virus

  16. Hepatitis C virus infection of cholangiocarcinoma cell lines

    NARCIS (Netherlands)

    Fletcher, Nicola F.; Humphreys, Elizabeth; Jennings, Elliott; Osburn, William; Lissauer, Samantha; Wilson, Garrick K.; van Ijzendoorn, Sven C. D.; Baumert, Thomas F.; Balfe, Peter; Afford, Simon; McKeating, Jane A.

    2015-01-01

    Hepatitis C virus (HCV) infects the liver and hepatocytes are the major cell type supporting viral replication. Hepatocytes and cholangiocytes derive from a common hepatic progenitor cell that proliferates during inflammatory conditions, raising the possibility that cholangiocytes may support HCV re

  17. Clinical significance of occult hepatitis B virus infection

    Institute of Scientific and Technical Information of China (English)

    Miriam Romero; Antonio Madejón; Conrado Fernández-Rodríguez; Javier García-Samaniego

    2011-01-01

    Occult hepatitis B virus (HBV) infection (OBI) is defined as the presence of HBV DNA in the liver (with or without detectable HBV DNA in serum) for individuals testing HBV surface antigen negative. Until recently, the clinical effect of OBI was unclear on the progression of liver disease; on the development of hepatocellular carcinoma; and on the risk for reactivation or transmission of HBV infection. Several studies suggest a high prevalence of OBI among patients with cryptogenic chronic liver disease, but its role in the progression to cirrhosis remains unclear. Although OBI has been well documented in human immunodeficiency virus (HIV)-positive patients, especially among those coinfected with hepatitis C virus, further studies are needed to determine its current clinical impact in HIV setting.

  18. Special Issue: Viruses Infecting Fish, Amphibians, and Reptiles

    Directory of Open Access Journals (Sweden)

    V. Gregory Chinchar

    2011-09-01

    Full Text Available Although viruses infecting and affecting humans are the focus of considerable research effort, viruses that target other animal species, including cold-blooded vertebrates, are receiving increased attention. In part this reflects the interests of comparative virologists, but increasingly it is based on the impact that many viruses have on ecologically and commercially important animals. Frogs and other amphibians are sentinels of environmental health and their disappearance following viral or fungal (chytrid infection is a cause for alarm. Likewise, because aquaculture and mariculture are providing an increasingly large percentage of the “seafood” consumed by humans, viral agents that adversely impact the harvest of cultured fish and amphibians are of equal concern. [...

  19. Evidence of Apeu Virus Infection in Wild Monkeys, Brazilian Amazon.

    Science.gov (United States)

    Oliveira, Danilo B; Luiz, Ana Paula Moreira Franco; Fagundes, Alexandre; Pinto, Carla Amaral; Bonjardim, Cláudio A; Trindade, Giliane S; Kroon, Erna G; Abrahão, Jônatas S; Ferreira, Paulo C P

    2016-03-01

    Orthobunyaviruses are arboviruses in which at least 30 members are human pathogens. The members of group C orthobunyaviruses were first isolated in the Brazilian Amazon in 1950, since that time little information is accumulated about ecology and the medical impact of these virus groups in Brazil. Herein, we describe the evidence of Apeu virus (APEUV; an Orthobunyavirus member) infection in wild monkeys from the Brazilian Amazon forest. APEUV was detected by using a neutralizing antibody in serum and its RNA, suggesting past and acute infection of Amazonian monkeys by this virus. These results altogether represent an important contribution of orthobunyavirus ecology in the Amazon and an update about recent circulation and risk for humans with expansion of the cities to Amazon forest.

  20. Zika Virus Infection and Microcephaly: Evidence for a Causal Link

    Directory of Open Access Journals (Sweden)

    Jin-Na Wang

    2016-10-01

    Full Text Available Zika virus (ZIKV is a flavivirus related to the Dengue, yellow fever and West Nile viruses. Since the explosive outbreaks of ZIKV in Latin America in 2015, a sudden increase in the number of microcephaly cases has been observed in infants of women who were pregnant when they contracted the virus. The severity of this condition raises grave concerns, and extensive studies on the possible link between ZIKV infection and microcephaly have been conducted. There is substantial evidence suggesting that there is a causal link between ZIKV and microcephaly, however, future studies are warranted to solidify this association. To summarize the most recent evidence on this issue and provide perspectives for future studies, we reviewed the literature to identify existing evidence of the causal link between ZIKV infection and microcephaly within research related to the epidemics, laboratory diagnosis, and possible mechanisms.

  1. Current Approaches for Diagnosis of Influenza Virus Infections in Humans

    Directory of Open Access Journals (Sweden)

    Sai Vikram Vemula

    2016-04-01

    Full Text Available Despite significant advancement in vaccine and virus research, influenza continues to be a major public health concern. Each year in the United States of America, influenza viruses are responsible for seasonal epidemics resulting in over 200,000 hospitalizations and 30,000–50,000 deaths. Accurate and early diagnosis of influenza viral infections are critical for rapid initiation of antiviral therapy to reduce influenza related morbidity and mortality both during seasonal epidemics and pandemics. Several different approaches are currently available for diagnosis of influenza infections in humans. These include viral isolation in cell culture, immunofluorescence assays, nucleic acid amplification tests, immunochromatography-based rapid diagnostic tests, etc. Newer diagnostic approaches are being developed to overcome the limitations associated with some of the conventional detection methods. This review discusses diagnostic approaches currently available for detection of influenza viruses in humans.

  2. Tuberculosis and human immunodeficiency virus infection.

    Science.gov (United States)

    Telzak, E E

    1997-03-01

    Mycobacterium tuberculosis infects one third of the world's population, and tuberculosis remains one of the most common infectious diseases of humans. From a global perspective, tuberculosis may be one of the most common HIV-related opportunistic infections. HIV immunosuppression has had a dramatic influence on the epidemiology, natural history and clinical presentation of tuberculosis. Treatment is highly effective for drug susceptible tuberculosis and has been shown to have a significant impact on resistant, especially multidrug-resistant, tuberculosis if started promptly. Directly observed therapy and rigorous adherence to infection control principles have helped control the tuberculosis epidemic in the United States.

  3. Differential sensitivity of bat cells to infection by enveloped RNA viruses: coronaviruses, paramyxoviruses, filoviruses, and influenza viruses.

    Directory of Open Access Journals (Sweden)

    Markus Hoffmann

    Full Text Available Bats (Chiroptera host major human pathogenic viruses including corona-, paramyxo, rhabdo- and filoviruses. We analyzed six different cell lines from either Yinpterochiroptera (including African flying foxes and a rhinolophid bat or Yangochiroptera (genera Carollia and Tadarida for susceptibility to infection by different enveloped RNA viruses. None of the cells were sensitive to infection by transmissible gastroenteritis virus (TGEV, a porcine coronavirus, or to infection mediated by the Spike (S protein of SARS-coronavirus (SARS-CoV incorporated into pseudotypes based on vesicular stomatitis virus (VSV. The resistance to infection was overcome if cells were transfected to express the respective cellular receptor, porcine aminopeptidase N for TGEV or angiotensin-converting enzyme 2 for SARS-CoV. VSV pseudotypes containing the S proteins of two bat SARS-related CoV (Bg08 and Rp3 were unable to infect any of the six tested bat cell lines. By contrast, viral pseudotypes containing the surface protein GP of Marburg virus from the family Filoviridae infected all six cell lines though at different efficiency. Notably, all cells were sensitive to infection by two paramyxoviruses (Sendai virus and bovine respiratory syncytial virus and three influenza viruses from different subtypes. These results indicate that bat cells are more resistant to infection by coronaviruses than to infection by paramyxoviruses, filoviruses and influenza viruses. Furthermore, these results show a receptor-dependent restriction of the infection of bat cells by CoV. The implications for the isolation of coronaviruses from bats are discussed.

  4. Migration of activated CD8(+) T lymphocytes to sites of viral infection does not require endothelial selectins

    DEFF Research Database (Denmark)

    Bartholdy, C; Marker, O; Thomsen, Allan Randrup

    2000-01-01

    Using mice deficient of E-selectin and E/P-selectin, we have studied the requirement for endothelial selectins in extravasation of leukocytes at sites of viral infection, with major emphasis on the recruitment of virus-specific T(C)1 cells. Lymphocytic choriomeningitis virus (LCMV)-induced mening......Using mice deficient of E-selectin and E/P-selectin, we have studied the requirement for endothelial selectins in extravasation of leukocytes at sites of viral infection, with major emphasis on the recruitment of virus-specific T(C)1 cells. Lymphocytic choriomeningitis virus (LCMV...... or marginal reduction was found in E/P-sel -/- mice, compared with wild-type mice after local challenge with virus or immunodominant viral MHC class I restricted peptide, respectively. Similar results were obtained after adoptive transfer of wild-type effector cells into E/P-sel -/- recipients, whereas...... footpad swelling was markedly decreased in P-sel/ICAM-1 -/- and ICAM-1 -/- recipients. LCMV-induced footpad swelling was completely inhibited in ICAM-deficient mice transfused with donor cell preincubated with soluble VCAM-1-Ig chimeric protein. Taken together, the current findings strongly indicate...

  5. Human Ebola virus infection results in substantial immune activation.

    Science.gov (United States)

    McElroy, Anita K; Akondy, Rama S; Davis, Carl W; Ellebedy, Ali H; Mehta, Aneesh K; Kraft, Colleen S; Lyon, G Marshall; Ribner, Bruce S; Varkey, Jay; Sidney, John; Sette, Alessandro; Campbell, Shelley; Ströher, Ute; Damon, Inger; Nichol, Stuart T; Spiropoulou, Christina F; Ahmed, Rafi

    2015-04-14

    Four Ebola patients received care at Emory University Hospital, presenting a unique opportunity to examine the cellular immune responses during acute Ebola virus infection. We found striking activation of both B and T cells in all four patients. Plasmablast frequencies were 10-50% of B cells, compared with less than 1% in healthy individuals. Many of these proliferating plasmablasts were IgG-positive, and this finding coincided with the presence of Ebola virus-specific IgG in the serum. Activated CD4 T cells ranged from 5 to 30%, compared with 1-2% in healthy controls. The most pronounced responses were seen in CD8 T cells, with over 50% of the CD8 T cells expressing markers of activation and proliferation. Taken together, these results suggest that all four patients developed robust immune responses during the acute phase of Ebola virus infection, a finding that would not have been predicted based on our current assumptions about the highly immunosuppressive nature of Ebola virus. Also, quite surprisingly, we found sustained immune activation after the virus was cleared from the plasma, observed most strikingly in the persistence of activated CD8 T cells, even 1 mo after the patients' discharge from the hospital. These results suggest continued antigen stimulation after resolution of the disease. From these convalescent time points, we identified CD4 and CD8 T-cell responses to several Ebola virus proteins, most notably the viral nucleoprotein. Knowledge of the viral proteins targeted by T cells during natural infection should be useful in designing vaccines against Ebola virus.

  6. Malignant syphilis with human immunodeficiency virus infection

    Directory of Open Access Journals (Sweden)

    Jiby Rajan

    2011-01-01

    Full Text Available Malignant syphilis or Lues maligna, commonly reported in the pre-antibiotic era, has now seen a resurgence with the advent of human immunodeficiency virus (HIV. Immunosuppression and sexual promiscuity set the stage for this deadly association of HIV and Treponema pallidum that can manifest atypically and can prove to cause diagnostic problems. We report one such case in a 30-year-old female who responded favorably to treatment with penicillin.

  7. Atypical Presentations of Respiratory Syncytial Virus Infection; Case series

    Directory of Open Access Journals (Sweden)

    Nawal Al-Maskari

    2016-02-01

    Full Text Available The respiratory syncytial virus (RSV usually causes a lower respiratory tract infection in affected patients. RSV has also been infrequently linked to extrapulmonary diseases in children. We report four children who had unusually severe clinical manifestations of RSV infections requiring critical care admission. These patients presented to the Royal Hospital, Muscat, Oman, in December 2013 with acute necrotising encephalopathy (ANE, acute fulminant hepatic failure with encephalopathy, pneumatoceles and croup. A unique presentation of ANE has not previously been reported in association with an RSV infection. All patients had a positive outcome and recovered fully with supportive management.

  8. Association of hepatitis C virus infection and diabetes

    Institute of Scientific and Technical Information of China (English)

    Samir Rouabhia; Rachid Malek; Hocine Bounecer

    2009-01-01

    Epidemiologic studies have suggested a relation between hepatitis C virus (HCV) infection and diabetes mellitus. HCV infection is emerging as a metabolic disease, and diabetes mellitus as a risk factor for HCV infection. However, some data on the prevalence of antibodies to HCV in patients with diabetes are conflicting. These seroprevalence data should be interpreted with caution. Some potential bias may occur in those clinic-based studies that target a specific disease group. In this letter we explain some reasons for these conflicting studies.

  9. Morphology and infectivity of virus that persistently caused infection in an AGS cell line.

    Science.gov (United States)

    Ooi, Yukimasa; Daikoku, Eriko; Wu, Hong; Aoki, Hiroaki; Morita, Chizuko; Nakano, Takashi; Kohno, Takehiro; Takasaki, Tomohiko; Sano, Kouichi

    2011-12-01

    A recent report has indicated that proteins and genes of simian virus 5 (SV5) are detected in a human gastric adenocarcinoma (AGS) cell line, which is widely provided for oncology, immunology, and microbiology research. However, the production of infective virions has not been determined in this cell line. In this study, the morphology and infectivity of the virus particles of the AGS cell line were studied by light and electron microscopy and virus transmission assay. The virus particles were approximately 176.0 ± 41.1 nm in diameter. The particles possessed projections 8-12 nm long on the surface and contained a nucleocapsid determined to be 13-18 nm in width and less than 1,000 nm in length. The virus was transmissible to the Vero cell line, induced multinuclear giant cell formation, and reproduced the same shape of antigenic virions. In this study, the persistently infected virus in the AGS cell line was determined to be infective and form reproducible virions, and a new morphological feature of SV5 was determined.

  10. Early pathogenesis of transmucosal feline immunodeficiency virus infection.

    Science.gov (United States)

    Obert, Leslie A; Hoover, Edward A

    2002-06-01

    To identify the early target cells and tissues in transmucosal feline immunodeficiency virus (FIV) infection, cats were exposed to a clade C FIV isolate via the oral-nasal or vaginal mucosa and multiple tissues were examined by virus isolation coculture (VI), DNA PCR, catalyzed tyramide signal-amplified in situ hybridization (TSA-ISH), and immunohistochemistry between days 1 and 12 postinoculation (p.i.). FIV RNA was detected in tonsil and oral or vaginal mucosa as early as 1 day p.i. by TSA-ISH and in retropharyngeal, tracheobronchial, or external iliac lymph nodes and sometimes in spleen or blood mononuclear cells by day 2, indicating that regional and distant spread of virus-infected cells occurred rapidly after mucosal exposure. By day 8, viral RNA, DNA, and culturable virus were uniformly detected in regional and distant tissues, connoting systemic infection. TSA-ISH proved more sensitive than DNA PCR in detecting early FIV-infected cells. In mucosal tissues, the earliest demonstrable FIV-bearing cells were either within or subjacent to the mucosal epithelium or were in germinal centers of regional lymph nodes. The FIV(+) cells were of either of two morphological types, large stellate or small round. Those FIV RNA(+) cells which could be colabeled for a phenotype marker, were labeled for either dendritic-cell-associated protein p55 or T-lymphocyte receptor antigen CD3. These studies indicate that FIV crosses mucous membranes within hours after exposure and rapidly traffics via dendritic and T cells to systemic lymphoid tissues, a pathway similar to that thought to occur in the initial phase of infection by the human and simian immunodeficiency viruses.

  11. Herpes simplex Virus Esophagitis in an Immunocompetent Patient with Ebstein-Barr Virus Infection

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    M. Tzouvala

    2008-11-01

    Full Text Available Epstein-Barr virus infectious mononucleosis can cause transient immune deficiency which may predispose to reactivation of latent herpes simplex virus (HSV infection in the immunocompetent host. We report the case of a 15-year-old male who presented with severe odynophagia and herpes labialis during the course of Epstein-Barr virus infectious mononucleosis that had been diagnosed ten days before. Esophagoscopy revealed extensive ulcerations with distinct borders and whitish exudates at the mid and distal esophagus. Polymerase chain reaction detected HSV-1 DNA in the biopsy specimens. The patient was treated with intravenous acyclovir. The symptoms resolved rapidly within 3 days, in accordance with improved endoscopic findings.

  12. Crosstalk between innate and adaptive immunity inhepatitis B virus infection

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Hepatitis B virus (HBV) infection is a major public health problem worldwide. HBV is not directly cytotoxic toinfected hepatocytes; the clinical outcome of infectionresults from complicated interactions between the virusand the host immune system. In acute HBV infection,initiation of a broad, vigorous immune response is responsiblefor viral clearance and self-limited inflammatoryliver disease. Effective and coordinated innate andadaptive immune responses are critical for viral clearanceand the development of long-lasting immunity. Chronichepatitis B patients fail to mount efficient innate andadaptive immune responses to the virus. In particular,HBV-specific cytotoxic T cells, which are crucial for HBVclearance, are hyporesponsiveness to HBV infection.Accumulating experimental evidence obtained fromthe development of animal and cell line models hashighlighted the importance of innate immunity in theearly control of HBV spread. The virus has evolvedimmune escape strategies, with higher HBV loads andHBV protein concentrations associated with increasingimpairment of immune function. Therefore, treatmentof HBV infection requires inhibition of HBV replicationand protein expression to restore the suppressedhost immunity. Complicated interactions exist notonly between innate and adaptive responses, but alsoamong innate immune cells and different components ofadaptive responses. Improved insight into these complexinteractions are important in designing new therapeuticstrategies for the treatment HBV infection. In thisreview, we summarize the current knowledge regardingthe cross-talk between the innate and adaptive immuneresponses and among different immunocytes in HBVinfection.

  13. The innate immune playbook for restricting West Nile virus infection.

    Science.gov (United States)

    Quicke, Kendra M; Suthar, Mehul S

    2013-10-30

    West Nile virus (WNV) is an emerging mosquito-borne flavivirus that causes annual epidemics of encephalitic disease throughout the world. Despite the ongoing risk to public health, no approved vaccines or therapies exist for use in humans to prevent or combat WNV infection. The innate immune response is critical for controlling WNV replication, limiting virus-induced pathology, and programming protective humoral and cell-mediated immunity to WNV infection. The RIG-I like receptors, Toll-like receptors, and Nod-like receptors detect and respond to WNV by inducing a potent antiviral defense program, characterized by production of type I IFN, IL-1β and expression of antiviral effector genes. Recent research efforts have focused on uncovering the mechanisms of innate immune sensing, antiviral effector genes that inhibit WNV, and countermeasures employed by WNV to antagonize innate immune cellular defenses. In this review, we highlight the major research findings pertaining to innate immune regulation of WNV infection.

  14. Chronic Ulcerative Herpes Simplex Virus Infection of the Vulva

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    Kelly Griffith-Bauer

    2012-09-01

    Full Text Available Herpes simplex virus infections in HIV-infected individuals can be clinically unusual and difficult to treat due to underlying problems with cell-mediated immunity and the occurrence of antiviral resistance. Additionally, partial or incomplete restoration of immune function may result in chronic ulcerations that require rotational treatments. In this report, we describe the case of a 38-year-old HIV-positive woman who developed the ulcerative form of chronic herpes simplex infection despite highly active antiretroviral therapy and valacyclovir prophylaxis. Repeated intravenous courses of foscarnet and topical cidofovir finally controlled her erosions as her cell-mediated immunity was slowly restored. This case highlights the challenges that still exist in diagnosing and managing this rare presentation of herpes simplex virus

  15. Mouse Models of Hepatitis B Virus Infection Comprising Host-Virus Immunologic Interactions

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    Tadashi Inuzuka

    2014-04-01

    Full Text Available Hepatitis B virus (HBV infection is one of the most prevalent infectious diseases associated with various human liver diseases, including acute, fulminant and chronic hepatitis; liver cirrhosis; and hepatocellular carcinoma. Despite the availability of an HBV vaccine and the development of antiviral therapies, there are still more than 350 million chronically infected people worldwide, approximately 5% of the world population. To understand the virus biology and pathogenesis in HBV-infected patients, several animal models have been developed to mimic hepatic HBV infection and the immune response against HBV, but the narrow host range of HBV infection and lack of a full immune response spectrum in animal models remain significant limitations. Accumulating evidence obtained from studies using a variety of mouse models that recapitulate hepatic HBV infection provides several clues for understanding host-virus immunologic interactions during HBV infection, whereas the determinants of the immune response required for HBV clearance are poorly defined. Therefore, adequate mouse models are urgently needed to elucidate the mechanism of HBV elimination and identify novel targets for antiviral therapies.

  16. Innate immune responses in hepatitis B virus (HBV) infection.

    Science.gov (United States)

    Busca, Aurelia; Kumar, Ashok

    2014-02-07

    Hepatitis B virus (HBV) infection has a low rate of chronicity compared to HCV infection, but chronic liver inflammation can evolve to life threatening complications. Experimental data from HBV infected chimpanzees and HBV transgenic mice have indicated that cytotoxic T cells are the main cell type responsible for inhibition of viral replication, but also for hepatocyte lysis during chronic HBV infection. Their lower activation and impaired function in later stages of infection was suggested as a possible mechanism that allowed for low levels of viral replication. The lack of an interferon response in these models also indicated the importance of adaptive immunity in clearing the infection. Increased knowledge of the signalling pathways and pathogen associated molecular patterns that govern activation of innate immunity in the early stages of viral infections in general has led to a re-evaluation of the innate immune system in HBV infection. Numerous studies have shown that HBV employs active strategies to evade innate immune responses and induce immunosuppression. Some of the immune components targeted by HBV include dendritic cells, natural killer cells, T regulatory cells and signalling pathways of the interferon response. This review will present the current understanding of innate immunity in HBV infection and of the challenges associated with clearing of the HBV infection.

  17. Undetectable hepatitis C virus RNA during syphilis infection in two HIV/HCV-co-infected patients

    DEFF Research Database (Denmark)

    Salado-Rasmussen, Kirsten; Knudsen, Andreas; Krarup, Henrik Bygum;

    2014-01-01

    BACKGROUND: Treponema pallidum, the causative agent of syphilis, elicits a vigorous immune response in the infected host. This study sought to describe the impact of syphilis infection on hepatitis C virus (HCV) RNA levels in patients with HIV and chronic HCV infection. METHODS: Patients...... with chronic HIV/HCV and syphilis co-infection were identified by their treating physicians from 1 October 2010 to 31 December 2013. Stored plasma samples obtained before, during, and after syphilis infection were analysed for interleukin (IL)-2, IL-4, IL-6, IL-8, IL-10, tumour necrosis factor alpha (TNF......-α), interferon gamma (IFN-γ), and IFN-γ-inducible protein 10 kDa (IP-10). RESULTS: Undetectable HCV RNA at the time of early latent syphilis infection was observed in 2 patients with HIV and chronic HCV infection. After treatment of the syphilis infection, HCV RNA levels increased again in patient 1, whereas...

  18. Management of hepatitis C virus infection in HIV/HCV co-infected patients: Clinical review

    Institute of Scientific and Technical Information of China (English)

    Ashwani K Singal; Bhupinderjit S Anand

    2009-01-01

    Nearly one fourth of individuals with human immunodeficiency virus (HIV) infection have hepatitis C virus (HCV) infection in the US and Western Europe. With the availability of highly active antiretroviral therapy and the consequent reduction in opportunistic infections, resulting in the prolongation of the life span of HIV-infected patients, HCV co-infection has emerged as a significant factor influencing the survival of HIV patients. Patients with HIV/HCV co-infection have a faster rate of fibrosis progression resulting in more frequent occurrences of cirrhosis, end-stage liver disease, and hepatocellular carcinoma. However, the mechanism of interaction between the two viruses is not completely understood. The treatment for HCV in co-infected patients is similar to that of HCV monoinfection; i.e., a combination of pegylated interferon and ribavirin. The presence of any barriers to anti- HCV therapy should be identified and eliminated in order to recruit all eligible patients. The response to treatment in co-infected patients is inferior compared to the response in patients with HCV mono-infection. The sustained virologic response rate is only 38% for genotype-1 and 75% for genotype-2 and -3 infections. Liver transplantation is no longer considered a contraindication for end-stage liver disease in coinfected patients. However, the 5 year survival rate is lower in co-infected patients compared to patients with HCV mono-infection (33% vs 72%, P = 0.07). A better understanding of liver disease in co-infected patients is needed to derive new strategies for improving outcome and survival.

  19. Immune regulation in chronic hepatitis C virus infection

    DEFF Research Database (Denmark)

    Hartling, Hans Jakob; Ballegaard, Vibe Cecilie; Nielsen, Nick Schou;

    2016-01-01

    The immunological result of infection with Hepatitis C virus (HCV) depends on the delicate balance between a vigorous immune response that may clear the infection, but with a risk of unspecific inflammation and, or a less inflammatory response that leads to chronic infection. In general, exhaustion...... and impairment of cytotoxic function of HCV-specific T cells and NK cells are found in patients with chronic HCV infection. In contrast, an increase in immune regulatory functions is found primarily in form of increased IL-10 production possibly due to increased level and function of anti-inflammatory Tregs....... Thus, the major immune players during chronic HCV infection are characterized by a decrease of cytotoxic function and increase of inhibitory functions. This may be an approach to diminish intrahepatic and systemic inflammation. Finally, there has been increasing awareness of regulatory functions...

  20. Hendra virus infection dynamics in Australian fruit bats.

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    Hume Field

    Full Text Available Hendra virus is a recently emerged zoonotic agent in Australia. Since first described in 1994, the virus has spilled from its wildlife reservoir (pteropid fruit bats, or 'flying foxes' on multiple occasions causing equine and human fatalities. We undertook a three-year longitudinal study to detect virus in the urine of free-living flying foxes (a putative route of excretion to investigate Hendra virus infection dynamics. Pooled urine samples collected off plastic sheets placed beneath roosting flying foxes were screened for Hendra virus genome by quantitative RT-PCR, using a set of primers and probe derived from the matrix protein gene. A total of 1672 pooled urine samples from 67 sampling events was collected and tested between 1 July 2008 and 30 June 2011, with 25% of sampling events and 2.5% of urine samples yielding detections. The proportion of positive samples was statistically associated with year and location. The findings indicate that Hendra virus excretion occurs periodically rather than continuously, and in geographically disparate flying fox populations in the state of Queensland. The lack of any detection in the Northern Territory suggests prevalence may vary across the range of flying foxes in Australia. Finally, our findings suggest that flying foxes can excrete virus at any time of year, and that the apparent seasonal clustering of Hendra virus incidents in horses and associated humans (70% have occurred June to October reflects factors other than the presence of virus. Identification of these factors will strengthen risk minimization strategies for horses and ultimately humans.

  1. Proteasome Inhibition Suppresses Dengue Virus Egress in Antibody Dependent Infection.

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    Milly M Choy

    2015-11-01

    Full Text Available The mosquito-borne dengue virus (DENV is a cause of significant global health burden, with an estimated 390 million infections occurring annually. However, no licensed vaccine or specific antiviral treatment for dengue is available. DENV interacts with host cell factors to complete its life cycle although this virus-host interplay remains to be fully elucidated. Many studies have identified the ubiquitin proteasome pathway (UPP to be important for successful DENV production, but how the UPP contributes to DENV life cycle as host factors remains ill defined. We show here that proteasome inhibition decouples infectious virus production from viral RNA replication in antibody-dependent infection of THP-1 cells. Molecular and imaging analyses in β-lactone treated THP-1 cells suggest that proteasome function does not prevent virus assembly but rather DENV egress. Intriguingly, the licensed proteasome inhibitor, bortezomib, is able to inhibit DENV titers at low nanomolar drug concentrations for different strains of all four serotypes of DENV in primary monocytes. Furthermore, bortezomib treatment of DENV-infected mice inhibited the spread of DENV in the spleen as well as the overall pathological changes. Our findings suggest that preventing DENV egress through proteasome inhibition could be a suitable therapeutic strategy against dengue.

  2. Liver histology in co-infection of hepatitis C virus (HCV and Hepatitis G virus (HGV

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    STRAUSS Edna

    2002-01-01

    Full Text Available As little is known about liver histology in the co-infection of hepatitis C virus (HCV and hepatitis G virus (HGV, HGV RNA was investigated in 46 blood donors with hepatitis C, 22 of them with liver biopsy: co-infection HCV / HGV (n = 6 and HCV isolated infection (n = 16. Besides staging and grading of inflammation at portal, peri-portal and lobular areas (Brazilian Consensus, the fibrosis progression index was also calculated. All patients had no symptoms or signs of liver disease and prevalence of HGV / HCV co-infection was 15.2%. Most patients had mild liver disease and fibrosis progression index, calculated only in patients with known duration of infection, was 0.110 for co-infection and 0.130 for isolated HCV infection, characterizing these patients as "slow fibrosers". No statistical differences could be found between the groups, although a lesser degree of inflammation was always present in co-infection. In conclusion co-infection HCV / HGV does not induce a more aggressive liver disease, supporting the hypothesis that HGV is not pathogenic.

  3. Modelling Virus and Antibody Dynamics during Dengue Virus Infection Suggests a Role for Antibody in Virus Clearance.

    Directory of Open Access Journals (Sweden)

    Hannah E Clapham

    2016-05-01

    Full Text Available Dengue is an infection of increasing global importance, yet uncertainty remains regarding critical aspects of its virology, immunology and epidemiology. One unanswered question is how infection is controlled and cleared during a dengue infection. Antibody is thought to play a role, but little past work has examined the kinetics of both virus and antibody during natural infections. We present data on multiple virus and antibody titres measurements recorded sequentially during infection from 53 Vietnamese dengue patients. We fit mechanistic mathematical models of the dynamics of viral replication and the host immune response to these data. These models fit the data well. The model with antibody removing virus fits the data best, but with a role suggested for ADCC or other infected cell clearance mechanisms. Our analysis therefore shows that the observed viral and antibody kinetics are consistent with antibody playing a key role in controlling viral replication. This work gives quantitative insight into the relationship between antibody levels and the efficiency of viral clearance. It will inform the future development of mechanistic models of how vaccines and antivirals might modify the course of natural dengue infection.

  4. Health care-associated hepatitis C virus infection.

    Science.gov (United States)

    Pozzetto, Bruno; Memmi, Meriam; Garraud, Olivier; Roblin, Xavier; Berthelot, Philippe

    2014-12-14

    Hepatitis C virus (HCV) is a blood-borne pathogen that has a worldwide distribution and infects millions of people. Care-associated HCV infections represented a huge part of hepatitis C burden in the past via contaminated blood and unsafe injections and continue to be a serious problem of public health. The present review proposes a panorama of health care-associated HCV infections via the three mode of contamination that have been identified: (1) infected patient to non-infected patient; (2) infected patient to non-infected health care worker (HCW); and (3) infected HCW to non infected patient. For each condition, the circumstances of contamination are described together with the means to prevent them. As a whole, the more important risk is represented by unsafe practices regarding injections, notably with the improper use of multidose vials used for multiple patients. The questions of occupational exposures and infected HCWs are also discussed. In terms of prevention and surveillance, the main arm for combating care-associated HCV infections is the implementation of standard precautions in all the fields of cares, with training programs and audits to verify their good application. HCWs must be sensitized to the risk of blood-borne pathogens, notably by the use of safety devices for injections and good hygiene practices in the operating theatre and in all the invasive procedures. The providers performing exposed-prone procedures must monitor their HCV serology regularly in order to detect early any primary infection and to treat it without delay. With the need to stay vigilant because HCV infection is often a hidden risk, it can be hoped that the number of people infected by HCV via health care will decrease very significantly in the next years.

  5. Tick-borne encephalitis virus infection in humans

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    Hrnjaković-Cvjetković Ivana

    2016-01-01

    Full Text Available Introduction. Tick-borne meningoencephalitis virus is a flavivirus that causes the most important vector-borne central nervous system infection in many countries of Europe and Asia. There are three subtypes of tick-borne encephalitis virus: European, Siberian and the Far-Eastern subtype. Transmission. In endemic areas, the virus remains in transmissive cycles between Ixodes ticks and small rodents. Clinical picture. In most cases (70−98% infection goes asymptomatically. In about one-third of meningitis cases, meningoencephalitis or meningomyelitis is developed. Postencephalytic syndrome may be the complication of the infection, presenting with neurological symptoms. Diagnosis. Etiologic diagnosis of tick-borne meningoencephalitis is only made on basis of laboratory analyses. Reverse transcription-polymerase chain reaction is used for determining the presence of virus in the blood and cerebrospinal fluid. Antibodies in blood and cerebrospinal fluid can be detected by serological tests. Prevention. The most efficient way to control this potentially severe disease with possible serious long-term consequences is vaccination. It should be recommended to persons who live or travel to endemic areas. Conclusion. In Serbia, tick-borne encephalitis virus infection belongs to the list of reportable diseases; however, there are no reported cases because the diagnostics is not performed routinely. We believe that the significance of this zoonosis must be examined in our country and some of its parts because of preliminary positive serological findings found out in Vojvodina as well as because of reported cases in neighboring countries such as Hungary and Croatia and its worldwide distribution.

  6. Characterization of Lethal Zika Virus Infection in AG129 Mice.

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    Matthew T Aliota

    2016-04-01

    Full Text Available Mosquito-borne Zika virus (ZIKV typically causes a mild and self-limiting illness known as Zika fever, which often is accompanied by maculopapular rash, headache, and myalgia. During the current outbreak in South America, ZIKV infection during pregnancy has been hypothesized to cause microcephaly and other diseases. The detection of ZIKV in fetal brain tissue supports this hypothesis. Because human infections with ZIKV historically have remained sporadic and, until recently, have been limited to small-scale epidemics, neither the disease caused by ZIKV nor the molecular determinants of virulence and/or pathogenicity have been well characterized. Here, we describe a small animal model for wild-type ZIKV of the Asian lineage.Using mice deficient in interferon α/β and Ɣ receptors (AG129 mice, we report that these animals were highly susceptible to ZIKV infection and disease, succumbing within seven to eight days. Rapid viremic dissemination was observed in visceral organs and brain; but only was associated with severe pathologies in the brain and muscle. Finally, these results were consistent across challenge routes, age of mice, and inoculum doses. These data represent a mouse model for ZIKV that is not dependent on adapting ZIKV to intracerebral passage in mice.Foot pad injection of AG129 mice with ZIKV represents a biologically relevant model for studying ZIKV infection and disease development following wild-type virus inoculation without the requirement for adaptation of the virus or intracerebral delivery of the virus. This newly developed Zika disease model can be exploited to identify determinants of ZIKV virulence and reveal molecular mechanisms that control the virus-host interaction, providing a framework for rational design of acute phase therapeutics and for vaccine efficacy testing.

  7. Serological evidence of Ebola virus infection in Indonesian orangutans.

    Directory of Open Access Journals (Sweden)

    Chairul A Nidom

    Full Text Available Ebola virus (EBOV and Marburg virus (MARV belong to the family Filoviridae and cause severe hemorrhagic fever in humans and nonhuman primates. Despite the discovery of EBOV (Reston virus in nonhuman primates and domestic pigs in the Philippines and the serological evidence for its infection of humans and fruit bats, information on the reservoirs and potential amplifying hosts for filoviruses in Asia is lacking. In this study, serum samples collected from 353 healthy Bornean orangutans (Pongo pygmaeus in Kalimantan Island, Indonesia, during the period from December 2005 to December 2006 were screened for filovirus-specific IgG antibodies using a highly sensitive enzyme-linked immunosorbent assay (ELISA with recombinant viral surface glycoprotein (GP antigens derived from multiple species of filoviruses (5 EBOV and 1 MARV species. Here we show that 18.4% (65/353 and 1.7% (6/353 of the samples were seropositive for EBOV and MARV, respectively, with little cross-reactivity among EBOV and MARV antigens. In these positive samples, IgG antibodies to viral internal proteins were also detected by immunoblotting. Interestingly, while the specificity for Reston virus, which has been recognized as an Asian filovirus, was the highest in only 1.4% (5/353 of the serum samples, the majority of EBOV-positive sera showed specificity to Zaire, Sudan, Cote d'Ivoire, or Bundibugyo viruses, all of which have been found so far only in Africa. These results suggest the existence of multiple species of filoviruses or unknown filovirus-related viruses in Indonesia, some of which are serologically similar to African EBOVs, and transmission of the viruses from yet unidentified reservoir hosts into the orangutan populations. Our findings point to the need for risk assessment and continued surveillance of filovirus infection of human and nonhuman primates, as well as wild and domestic animals, in Asia.

  8. Inhibition of a plant virus infection by analogs of melittin.

    Science.gov (United States)

    Marcos, J F; Beachy, R N; Houghten, R A; Blondelle, S E; Pérez-Payá, E

    1995-01-01

    An approach that enables identification of specific synthetic peptide inhibitors of plant viral infection is reported. Synthetic analogs of melittin that have sequence and structural similarities to an essential domain of tobacco mosaic virus coat protein were found to possess highly specific antiviral activity. This approach involves modification of residues located at positions analogous to those that are critical for virus assembly. The degree of inhibition found correlates well with sequence similarities between the viral capsid protein and the melittin analogs studied as well as with the induced conformational changes that result upon interaction of the peptides and ribonucleic acid. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:8618922

  9. Early Pathogenesis of Transmucosal Feline Immunodeficiency Virus Infection

    OpenAIRE

    Obert, Leslie A.; Hoover, Edward A.

    2002-01-01

    To identify the early target cells and tissues in transmucosal feline immunodeficiency virus (FIV) infection, cats were exposed to a clade C FIV isolate via the oral-nasal or vaginal mucosa and multiple tissues were examined by virus isolation coculture (VI), DNA PCR, catalyzed tyramide signal-amplified in situ hybridization (TSA-ISH), and immunohistochemistry between days 1 and 12 postinoculation (p.i.). FIV RNA was detected in tonsil and oral or vaginal mucosa as early as 1 day p.i. by TSA-...

  10. Liver immune-pathogenesis and therapy of human liver tropic virus infection in humanized mouse models

    OpenAIRE

    Bility, Moses T.; Li, Feng; Cheng, Liang; Su, Lishan

    2013-01-01

    Hepatitis B virus (HBV) and hepatitis C virus (HCV) infect and replicate primarily in human hepatocytes. Few reliable and easy accessible animal models are available for studying the immune system’s contribution to the liver disease progression during hepatitis virus infection. Humanized mouse models reconstituted with human hematopoietic stem cells (HSCs) have been developed to study human immunology, human immunodeficiency virus 1 infection, and immunopathogenesis. However, a humanized mous...

  11. Inhibition of Bim enhances replication of varicella-zoster virus and delays plaque formation in virus-infected cells.

    Science.gov (United States)

    Liu, Xueqiao; Cohen, Jeffrey I

    2014-01-01

    Programmed cell death (apoptosis) is an important host defense mechanism against intracellular pathogens, such as viruses. Accordingly, viruses have evolved multiple mechanisms to modulate apoptosis to enhance replication. Varicella-zoster virus (VZV) induces apoptosis in human fibroblasts and melanoma cells. We found that VZV triggered the phosphorylation of the proapoptotic proteins Bim and BAD but had little or no effect on other Bcl-2 family members. Since phosphorylation of Bim and BAD reduces their proapoptotic activity, this may prevent or delay apoptosis in VZV-infected cells. Phosphorylation of Bim but not BAD in VZV-infected cells was dependent on activation of the MEK/extracellular signal-regulated kinase (ERK) pathway. Cells knocked down for Bim showed delayed VZV plaque formation, resulting in longer survival of VZV-infected cells and increased replication of virus, compared with wild-type cells infected with virus. Conversely, overexpression of Bim resulted in earlier plaque formation, smaller plaques, reduced virus replication, and increased caspase 3 activity. Inhibition of caspase activity in VZV-infected cells overexpressing Bim restored levels of virus production similar to those seen with virus-infected wild-type cells. Previously we showed that VZV ORF12 activates ERK and inhibits apoptosis in virus-infected cells. Here we found that VZV ORF12 contributes to Bim and BAD phosphorylation. In summary, VZV triggers Bim phosphorylation; reduction of Bim levels results in longer survival of VZV-infected cells and increased VZV replication.

  12. Modeling Powassan virus infection in Peromyscus leucopus, a natural host

    Science.gov (United States)

    Meade-White, Kimberly; Saturday, Greg; Scott, Dana; Bloom, Marshall E.

    2017-01-01

    The tick-borne flavivirus, Powassan virus (POWV) causes life-threatening encephalitis in humans in North America and Europe. POWV is transmitted by ixodid tick vectors that feed on small to medium-sized mammals, such as Peromyscus leucopus mice, which may serve as either reservoir, bridge or amplification hosts. Intraperitoneal and intracranial inoculation of 4-week old Peromyscus leucopus mice with 103 PFU of POWV did not result in overt clinical signs of disease. However, following intracranial inoculation, infected mice seroconverted to POWV and histopathological examinations revealed that the mice uniformly developed mild lymphocytic perivascular cuffing and microgliosis in the brain and spinal cord from 5 to 15 days post infection (dpi), suggesting an early inflammatory response. In contrast, intracranial inoculation of 4-week old C57BL/6 and BALB/c mice was lethal by 5 dpi. Intraperitoneal inoculation was lethal in BALB/c mice, but 40% (2/5) of C57BL/6 mice survived. We concluded that Peromyscus leucopus mice infected i.c. with a lethal dose of POWV support a limited infection, restricted to the central nervous system and mount an antibody response to the virus. However, they fail to develop clinical signs of disease and are able to control the infection. These results suggest the involvement of restriction factors, and the mechanism by which Peromyscus leucopus mice restrict POWV infection remains under study. PMID:28141800

  13. Molecular Biology and Infection of Hepatitis E Virus

    Directory of Open Access Journals (Sweden)

    Yuchen Nan

    2016-09-01

    Full Text Available Hepatitis E virus (HEV is a viral pathogen transmitted primarily via fecal-oral route. In humans, HEV mainly causes acute hepatitis and is responsible for large outbreaks of hepatitis across the world. The case fatality rate of HEV-induced hepatitis ranges from 0.5 to 3% in young adults and up to 30% in infected pregnant women. HEV strains infecting humans are classified into four genotypes. HEV strains from genotype 3 and 4 are zoonotic, whereas those from genotype 1 and 2 have no known animal reservoirs. Recently, notable progress has been accomplished for better understanding of HEV biology and infection, such as chronic HEV infection, in vitro cell culture system, quasi-enveloped HEV virions, functions of the HEV proteins, mechanism of HEV antagonizing host innate immunity, HEV pathogenesis and vaccine development. However, further investigation on the cross-species HEV infection, host tropism, vaccine efficacy and HEV-specific antiviral strategy is still needed. This review mainly focuses on molecular biology and infection of HEV and offers perspective new insight of this enigmatic virus.

  14. Molecular Biology and Infection of Hepatitis E Virus

    Science.gov (United States)

    Nan, Yuchen; Zhang, Yan-Jin

    2016-01-01

    Hepatitis E virus (HEV) is a viral pathogen transmitted primarily via fecal-oral route. In humans, HEV mainly causes acute hepatitis and is responsible for large outbreaks of hepatitis across the world. The case fatality rate of HEV-induced hepatitis ranges from 0.5 to 3% in young adults and up to 30% in infected pregnant women. HEV strains infecting humans are classified into four genotypes. HEV strains from genotypes 3 and 4 are zoonotic, whereas those from genotypes 1 and 2 have no known animal reservoirs. Recently, notable progress has been accomplished for better understanding of HEV biology and infection, such as chronic HEV infection, in vitro cell culture system, quasi-enveloped HEV virions, functions of the HEV proteins, mechanism of HEV antagonizing host innate immunity, HEV pathogenesis and vaccine development. However, further investigation on the cross-species HEV infection, host tropism, vaccine efficacy, and HEV-specific antiviral strategy is still needed. This review mainly focuses on molecular biology and infection of HEV and offers perspective new insight of this enigmatic virus. PMID:27656178

  15. Chayote mosaic virus, a New Tymovirus Infecting Cucurbitaceae.

    Science.gov (United States)

    Bernal, J J; Jiménez, I; Moreno, M; Hord, M; Rivera, C; Koenig, R; Rodríguez-Cerezo, E

    2000-10-01

    ABSTRACT Chayote mosaic virus (ChMV) is a putative tymovirus isolated from chayote crops in Costa Rica. ChMV was characterized at the host range, serological, and molecular levels. ChMV was transmitted mechanically and induced disease symptoms mainly in Cucurbitaceae hosts. Asymptomatic infections were detected in other host families. Serologically, ChMV is related to the Andean potato latent virus (APLV) and the Eggplant mosaic virus (EMV), both members of the genus Tymovirus infecting solanaceous hosts in the Caribbean Basin and South America. The sequence of the genomic RNA of ChMV was determined and its genetic organization was typical of tymoviruses. Comparisons with other tymoviral sequences showed that ChMV was a new member of the genus Tymovirus. The phylogenetic analyses of the coat protein gene were consistent with serological comparisons and positioned ChMV within a cluster of tymoviruses infecting mainly cucurbit or solanaceous hosts, including APLV and EMV. Phylogenetic analyses of the replicase protein gene confirmed the close relationship of ChMV and EMV. Our results suggest that ChMV is related to two tymoviruses (APLV and EMV) of proximal geographical provenance but with different natural host ranges. ChMV is the first cucurbit-infecting tymovirus to be fully characterized at the genomic level.

  16. Innate immune interferon responses to human immunodeficiency virus-1 infection.

    Science.gov (United States)

    Hughes, Rose; Towers, Greg; Noursadeghi, Mahdad

    2012-07-01

    Type I interferon (IFN) responses represent the canonical host innate immune response to viruses, which serves to upregulate expression of antiviral restriction factors and augment adaptive immune defences. There is clear evidence for type I IFN activity in both acute and chronic HIV-1 infection in vivo, and plasmacytoid dendritic cells have been identified as one important source for these responses, through innate immune detection of viral RNA by Toll-like receptor 7. In addition, new insights into the molecular mechanisms that trigger induction of type I IFNs suggest innate immune receptors for viral DNA may also mediate these responses. It is widely recognised that HIV-1 restriction factors share the characteristic of IFN-inducible expression, and that the virus has evolved to counteract these antiviral mechanisms. However, in some target cells, such as macrophages, IFN can still effectively restrict virus. In this context, HIV-1 shows the ability to evade innate immune recognition and thereby avoid induction of type I IFN in order to successfully establish productive infection. The relative importance of evasion of innate immune detection and evasion of IFN-inducible restriction in the natural history of HIV-1 infection is not known, and the data suggest that type I IFN responses may play a role in both viral control and in the immunopathogenesis of progressive disease. Further study of the relationship between HIV-1 infection and type I IFN responses is required to unravel these issues and inform the development of novel therapeutics or vaccine strategies.

  17. Zika virus infection damages the testes in mice.

    Science.gov (United States)

    Govero, Jennifer; Esakky, Prabagaran; Scheaffer, Suzanne M; Fernandez, Estefania; Drury, Andrea; Platt, Derek J; Gorman, Matthew J; Richner, Justin M; Caine, Elizabeth A; Salazar, Vanessa; Moley, Kelle H; Diamond, Michael S

    2016-12-15

    Infection of pregnant women with Zika virus (ZIKV) can cause congenital malformations including microcephaly, which has focused global attention on this emerging pathogen. In addition to transmission by mosquitoes, ZIKV can be detected in the seminal fluid of affected males for extended periods of time and transmitted sexually. Here, using a mouse-adapted African ZIKV strain (Dakar 41519), we evaluated the consequences of infection in the male reproductive tract of mice. We observed persistence of ZIKV, but not the closely related dengue virus (DENV), in the testis and epididymis of male mice, and this was associated with tissue injury that caused diminished testosterone and inhibin B levels and oligospermia. ZIKV preferentially infected spermatogonia, primary spermatocytes and Sertoli cells in the testis, resulting in cell death and destruction of the seminiferous tubules. Less damage was caused by a contemporary Asian ZIKV strain (H/PF/2013), in part because this virus replicates less efficiently in mice. The extent to which these observations in mice translate to humans remains unclear, but longitudinal studies of sperm function and viability in ZIKV-infected humans seem warranted.

  18. High Prevalence of Hepatitis B Virus Markers in Romanian Adolescents With Human Immunodeficiency Virus Infection

    Directory of Open Access Journals (Sweden)

    Ruta Simona

    2005-03-01

    Full Text Available Abstract Background We evaluated the frequency of hepatitis coinfection in Romanian adolescents who were diagnosed with human immunodeficiency virus (HIV infection prior to 1995. Methods One hundred sixty-one adolescents (13–18 years of age with symptomatic HIV infection, but without signs of hepatic dysfunction, and 356 age-matched, HIV-uninfected controls underwent laboratory testing for markers of parenterally acquired hepatitis virus infection. Results Seventy-eight percent of HIV-infected adolescents had markers of past or present hepatitis B virus (HBV infection, as compared with 32% of controls (P = .0001. The prevalence of HBV replicative markers was more than 5-fold higher in HIV-infected adolescents as compared with controls: 43.4% vs 7.9% (P = .0001, respectively, for hepatitis B surface antigen (HBsAg; and 11.2% vs 2.2% (P = .0001, respectively, for hepatitis B e antigen (HBeAg. The prevalence of HBsAg chronic carriers and the presence of HBV replicative markers was significantly higher in patients with immunologically defined AIDS (CD4+ cell counts P = .02 for HBsAg and 22.8% vs 5.7%, (P = .002 for HBV DNA. After 1 year of follow-up, the proportion of those who cleared the HBeAg was considerably lower in severely immunosuppressed coinfected patients: 4.7% vs 37.1% (P = .003. Four additional HIV-infected adolescents became HBsAg-positive over the term of follow-up (incidence rate, 24.9/1000 person-years, despite a record of immunization against hepatitis B. Conclusion A substantial percentage of HIV-infected and HIV-uninfected Romanian adolescents have evidence of past or present HBV infection. In HIV-infected adolescents, the degree of immunosuppression is correlated with persistence of HBV replicative markers, even in the absence of clinical or biochemical signs of liver disease.

  19. Temporal Analysis of Andes Virus and Sin Nombre Virus Infections of Syrian Hamsters▿

    Science.gov (United States)

    Wahl-Jensen, Victoria; Chapman, Jennifer; Asher, Ludmila; Fisher, Robert; Zimmerman, Michael; Larsen, Tom; Hooper, Jay W.

    2007-01-01

    Andes virus (ANDV) and Sin Nombre virus (SNV) are rodent-borne hantaviruses that cause a highly lethal hemorrhagic fever in humans known as hantavirus pulmonary syndrome (HPS). There are no vaccines or specific drugs to prevent or treat HPS, and the pathogenesis is not understood. Syrian hamsters infected with ANDV, but not SNV, develop a highly lethal disease that closely resembles HPS in humans. Here, we performed a temporal pathogenesis study comparing ANDV and SNV infections in hamsters. SNV was nonpathogenic and viremia was not detected despite the fact that all animals were infected. ANDV was uniformly lethal with a mean time to death of 11 days. The first pathology detected was lymphocyte apoptosis starting on day 4. Animals were viremic and viral antigen was first observed in multiple organs by days 6 and 8, respectively. Levels of infectious virus in the blood increased 4 to 5 logs between days 6 and 8. Pulmonary edema was first detected ultrastructurally on day 6. Ultrastructural analysis of lung tissues revealed the presence of large inclusion bodies and substantial numbers of vacuoles within infected endothelial cells. Paraendothelial gaps were not observed, suggesting that fluid leakage was transcellular and directly attributable to infecting virus. Taken together, these data imply that HPS treatment strategies aimed at preventing virus replication and dissemination will have the greatest probability of success if administered before the viremic phase; however, because vascular leakage is associated with infected endothelial cells, a therapeutic strategy targeting viral replication might be effective even at later times (e.g., after disease onset). PMID:17475651

  20. Tuberculous meningitis in patients infected with human immunodeficiency virus.

    Science.gov (United States)

    Garg, Ravindra Kumar; Sinha, Manish Kumar

    2011-01-01

    Tuberculosis is the most common opportunistic infection in human immunodeficiency virus (HIV) infected persons. HIV-infected patients have a high incidence of tuberculous meningitis as well. The exact incidence and prevalence of tuberculous meningitis in HIV-infected patients are not known. HIV infection does not significantly alter the clinical manifestations, laboratory, radiographic findings, or the response to therapy. Still, some differences have been noted. For example, the histopathological examination of exudates in HIV-infected patients shows fewer lymphocytes, epithelioid cells, and Langhan's type of giant cells. Larger numbers of acid-fast bacilli may be seen in the cerebral parenchyma and meninges. The chest radiograph is abnormal in up to 46% of patients with tuberculous meningitis. Tuberculous meningitis is likely to present with cerebral infarcts and mass lesions. Cryptococcal meningitis is important in differential diagnosis. The recommended duration of treatment in HIV-infected patients is 9-12 months. The benefit of adjunctive corticosteroids is uncertain. Antiretroviral therapy and antituberculosis treatment should be initiated at the same time, regardless of CD4 cell counts. Tuberculous meningitis may be a manifestation of paradoxical tuberculosis-associated immune reconstitution inflammatory syndrome. Some studies have demonstrated a significant impact of HIV co-infection on mortality from tuberculous meningitis. HIV-infected patients with multidrug-resistant tuberculous meningitis have significantly higher mortality. The best way to prevent HIV-associated tuberculous meningitis is to diagnose and isolate infectious cases of tuberculosis promptly and administer appropriate treatment.

  1. The Natural History of Hepatitis C Virus (HCV Infection

    Directory of Open Access Journals (Sweden)

    2006-04-01

    Full Text Available Hepatitis C virus (HCV is a leading cause of chronic liver disease, cirrhosis, and hepatocellular carcinoma, as well as the most common indication for liver transplantation in many countries. Although the incidence of hepatitis C infection has dramatically decreased during the past decade, the worldwide reservoir of chronically infected persons is estimated at 170 million, or 3% of the global population. There is much controversy surrounding the natural history of hepatitis C infection. The rate of chronic HCV infection is affected by a person's age, gender, race, and viral immune response. Approximately 75%-85% of HCV-infected persons will progress to chronic HCV infection, and are at risk for the development of extrahepatic manifestations, compensated and decompensated cirrhosis, and hepatocellular carcinoma (HCC. The rate of progression to cirrhosis is highly variable, and is influenced by several factors, including the amount of alcohol consumption, age of initial HCV infection, degree of inflammation and fibrosis on liver biopsy, HIV and HBV coinfection, and comordid conditions. An estimated 10%-15% of HCV-infected persons will advance to cirrhosis within the first 20 years. Persons with cirrhosis are at increased risk of developing HCC. An understanding of the natural history of hepatitis C is essential to effectively manage, treat, and counsel individuals with HCV infection.

  2. Begomoviruses infecting weeds in Cuba: increased host range and a novel virus infecting Sida rhombifolia.

    Science.gov (United States)

    Fiallo-Olivé, Elvira; Navas-Castillo, Jesús; Moriones, Enrique; Martínez-Zubiaur, Yamila

    2012-01-01

    As a result of surveys conducted during the last few years to search for wild reservoirs of begomoviruses in Cuba, we detected a novel bipartite begomovirus, sida yellow mottle virus (SiYMoV), infecting Sida rhombifolia plants. The complete genome sequence was obtained, showing that DNA-A was 2622 nucleotides (nt) in length and that it was most closely related (87.6% nucleotide identity) to DNA-A of an isolate of sida golden mosaic virus (SiGMV) that infects snap beans (Phaseolus vulgaris) in Florida. The DNA-B sequence was 2600 nt in length and shared the highest nucleotide identity (75.1%) with corchorus yellow spot virus (CoYSV). Phylogenetic relationship analysis showed that both DNA components of SiYMoV were grouped in the Abutilon clade, along with begomoviruses from Florida and the Caribbean islands. We also present here the complete nucleotide sequence of a novel strain of sida yellow vein virus found infecting Malvastrum coromandelianum and an isolate of euphorbia mosaic virus that was found for the first time infecting Euphorbia heterophylla in Cuba.

  3. Considerations in the Use of Nonhuman Primate Models of Ebola Virus and Marburg Virus Infection.

    Science.gov (United States)

    Geisbert, Thomas W; Strong, James E; Feldmann, Heinz

    2015-10-01

    The filoviruses, Ebola virus and Marburg virus, are zoonotic pathogens that cause severe hemorrhagic fever in humans and nonhuman primates (NHPs), with case-fatality rates ranging from 23% to 90%. The current outbreak of Ebola virus infection in West Africa, with >26 000 cases, demonstrates the long-underestimated public health danger that filoviruses pose as natural human pathogens. Currently, there are no vaccines or treatments licensed for human use. Licensure of any medical countermeasure may require demonstration of efficacy in the gold standard cynomolgus or rhesus macaque models of filovirus infection. Substantial progress has been made over the last decade in characterizing the filovirus NHP models. However, there is considerable debate over a variety of experimental conditions, including differences among filovirus isolates used, routes and doses of exposure, and euthanasia criteria, all of which may contribute to variability of results among different laboratories. As an example of the importance of understanding these differences, recent data with Ebola virus shows that an addition of a single uridine residue in the glycoprotein gene at the editing site attenuates the virus. Here, we draw on decades of experience working with filovirus-infected NHPs to provide a perspective on the importance of various experimental conditions.

  4. Antibody response of rainbow trout with single or double infections involving viral haemorrhagic septicaemia virus and infectious haematopoietic necrosis virus

    DEFF Research Database (Denmark)

    Fregeneda-Grandes, Juan Miguel; Skall, Helle Frank; Olesen, Niels Jørgen

    2009-01-01

    Juvenile rainbow trout Oncorhynchus mykiss were experimentally infected by immersion with viral haemorrhagic septicaemia virus (VHSV), infectious haematopoietic necrosis virus (IHNV) or with both viruses. The presence of neutralizing antibodies in the sera of infected fish were analysed by 50......% plaque neutralization tests (50%PNT). In Group 1 (infected with VHSV) and Group 2 (infected with IHNV) neutralizing antibodies were found in 41% and 21% of the serum samples, respectively. No cross-reacting antibodies were found in these 2 groups. In Group 3 (infected with both viruses) 30......% of the samples showed neutralizing antibodies against VHSV, 21% against IHNV and 12% against both viruses. Fish in Group 3 developed a double specific antibody reaction whose kinetics and intensity (mean of log10 titres) were similar to the antibody response of the single infected groups....

  5. Infection Functions for Virus Propagation in Computer Networks: An Empirical Study

    Institute of Scientific and Technical Information of China (English)

    YUAN Hua; WU Junjie; CHEN Guoqing

    2009-01-01

    There has been an increasing amount of interest in modeling virus propagation in recent years. However, the group-based infection mechanism of computer viruses is not well understood and the selec-tion of infection function in virus propagation modeling has not been well studied. This paper describes a point-to-group (P2G) infection mode to describe" virus propagation in networks with information sharing groups. Simulations compare the constant infection and I-type infection functions with the new E-type infec-lion function in the small-world-network environment. The simulation results show that the E-type infection function shows supedor performances to that of the traditional I-type infection function in modeling the P2G virus infection mechanism and the Ⅰ-type infection function shows better performance in modeling the ran-dom infection mechanism.

  6. Immunological aspects of antiviral therapy of chronic hepatitis B virus and hepatitis C virus infections.

    Science.gov (United States)

    Rehermann, Barbara; Bertoletti, Antonio

    2015-02-01

    Hepatitis B virus (HBV) and hepatitis C virus (HCV) cause a large proportion of acute and chronic liver disease worldwide. Over the past decades many immunological studies defined host immune responses that mediate spontaneous clearance of acute HBV and HCV infection. However, host immune responses are also relevant in the context of treatment-induced clearance of chronic HBV and HCV infection. First, the pretreatment level of interferon-stimulated genes as well as genetic determinants of innate immune responses, such as single nucleotide polymorphisms near the IFNL3 gene, are strong predictors of the response to interferon-alpha (IFN-α)-based therapy. Second, IFN-α, which has been a mainstay of HBV and HCV therapy over decades, and ribavirin, which has also been included in interferon-free direct antiviral therapy for HCV, modulate host immune responses. Third, both IFN-α-based and IFN-α-free treatment regimens of HBV and HCV infection alter the short-term and long-term adaptive immune response against these viruses. Finally, treatment studies have not just improved the clinical outcomes, but also provided opportunities to study virus-host interaction. This review summarizes our current knowledge on how a patient's immune response affects the treatment outcome of HBV and HCV infection and how innate and adaptive immune responses themselves are altered by the different treatment regimens.

  7. Tomato bushy stunt virus (TBSV) infecting Lycopersicon esculentum.

    Science.gov (United States)

    Hafez, El Sayed E; Saber, Ghada A; Fattouh, Faiza A

    2010-01-01

    Tomato bushy stunt virus (TBSV) was detected in tomato crop (Lycopersicon esculentum) in Egypt with characteristic mosaic leaf deformation, stunting, and bushy growth symptoms. TBSV infection was confirmed serologically by ELISA and calculated incidence was 25.5%. Basic physicochemical properties of a purified TBSV Egh isolate were identical to known properties of tombusviruses of isometric 30-nm diameter particles, 41-kDa coat protein and the genome of approximately 4800 nt. This is the first TBSV isolate reported in Egypt. Cloning and partial sequencing of the isolate showed that it is more closely related to TBSV-P and TBSV-Ch than TBSV-Nf and TBSV-S strains of the virus. However, it is distinct from the above strains and could be a new strain of the virus which further confirms the genetic diversity of tombusviruses.

  8. Annual Incidence of Lassa Virus Infection in Southern Mali.

    Science.gov (United States)

    Safronetz, David; Sogoba, Nafomon; Diawara, Sory Ibrahim; Bane, Sidy; Rosenke, Kyle; Maiga, Ousmane; Boisen, Matt; Garry, Robert F; Branco, Luis M; Lindsay, L Robbin; Traoré, Sékou F; Feldmann, Heinz; Doumbia, Seydou

    2017-01-16

    Previously, we reported a high seroprevalence rate of Lassa virus antibodies in inhabitants of three villages in southern Mali where infected rodents have been demonstrated. Herein, we report a 1-year follow-up study in which we were able to collect a second blood samples from 88.7% of participants of the same cohort. We identified 23 seroconversions for IgG antibodies reactive against Lassa virus, representing an incidence of 6.3% (95% confidence interval = 3.8-8.8%). Seroconversion was frequently seen in preteenage children (12/23, 51.7%) and two household/familial clusters were identified. These results confirm active transmission of Lassa virus is occurring in southern Mali and appropriate diagnostic testing should be established for this often severe etiological agent viral hemorrhagic fever.

  9. Gene silencing: a therapeutic approach to combat influenza virus infections.

    Science.gov (United States)

    Khanna, Madhu; Saxena, Latika; Rajput, Roopali; Kumar, Binod; Prasad, Rajendra

    2015-01-01

    Selective gene silencing technologies such as RNA interference (RNAi) and nucleic acid enzymes have shown therapeutic potential for treating viral infections. Influenza virus is one of the major public health concerns around the world and its management is challenging due to a rapid increase in antiviral resistance. Influenza vaccine also has its limitations due to the emergence of new strains that may escape the immunity developed by the previous year's vaccine. Antiviral drugs are the primary mode of prevention and control against a pandemic and there is an urgency to develop novel antiviral strategies against influenza virus. In this review, we discuss the potential utility of several gene silencing mechanisms and their prophylactic and therapeutic potential against the influenza virus.

  10. High seroprevalence of herpes simplex virus type 2 infection in French human immunodeficiency virus type 1-infected outpatients.

    Science.gov (United States)

    Andréoletti, Laurent; Piednoir, Emmanuel; Legoff, Jérôme; Brodard, Véronique; Beguinot, Isabelle; Strady, Christophe; Rouger, Christine; Piketty, Christophe; Si-Mohamed, Ali; Kazatchkine, Michel Daniel; Malkin, Jean-Elie; Bélec, Laurent

    2005-08-01

    Using commercially available herpes simplex virus (HSV) type-specific serological diagnostic tests, HSV type 2 (HSV-2) antibody prevalence was assessed in two parallel prospective studies including 534 human immunodeficiency virus type 1 (HIV-1)-infected outpatients living in two areas of northern France. In the first cohort of 434 subjects, 223 (51%) individuals demonstrated a positive HSV-2 serological status while 66 (66%) of 100 subjects in the second cohort were seropositive for HSV-2 (51 versus 66%; P = 0.08). Among the 223 HSV-2-seropositive subjects identified in the first study cohort, only 22 (10%) had suffered from recurrent anogenital lesions during the past 12 months while 154 (69%) had no clinical history of herpesvirus infection. Our findings demonstrate high proportions of subclinical and undiagnosed HSV-2 infection in HIV-1-infected individuals and suggest that HSV type-specific serological testing in the French HIV-1-infected subpopulation could be an efficient strategy to diagnose clinically asymptomatic HSV-2 infections.

  11. Simian varicella virus infection of rhesus macaques recapitulates essential features of varicella zoster virus infection in humans.

    Directory of Open Access Journals (Sweden)

    Ilhem Messaoudi

    2009-11-01

    Full Text Available Simian varicella virus (SVV, the etiologic agent of naturally occurring varicella in primates, is genetically and antigenically closely related to human varicella zoster virus (VZV. Early attempts to develop a model of VZV pathogenesis and latency in nonhuman primates (NHP resulted in persistent infection. More recent models successfully produced latency; however, only a minority of monkeys became viremic and seroconverted. Thus, previous NHP models were not ideally suited to analyze the immune response to SVV during acute infection and the transition to latency. Here, we show for the first time that intrabronchial inoculation of rhesus macaques with SVV closely mimics naturally occurring varicella (chickenpox in humans. Infected monkeys developed varicella and viremia that resolved 21 days after infection. Months later, viral DNA was detected only in ganglia and not in non-ganglionic tissues. Like VZV latency in human ganglia, transcripts corresponding to SVV ORFs 21, 62, 63 and 66, but not ORF 40, were detected by RT-PCR. In addition, as described for VZV, SVV ORF 63 protein was detected in the cytoplasm of neurons in latently infected monkey ganglia by immunohistochemistry. We also present the first in depth analysis of the immune response to SVV. Infected animals produced a strong humoral and cell-mediated immune response to SVV, as assessed by immunohistology, serology and flow cytometry. Intrabronchial inoculation of rhesus macaques with SVV provides a novel model to analyze viral and immunological mechanisms of VZV latency and reactivation.

  12. Host susceptibility to persistent hepatitis B virus infection

    Institute of Scientific and Technical Information of China (English)

    Ying-Li He; Ying-Ren Zhao; Shu-Lin Zhang; Shu-Mei Lin

    2006-01-01

    Genetic epidemiology researches such as twin studies, family-clustering of hepatitis B virus (HBV) infection studies and ethnic difference studies have provided the evidence that host genetic factors play an important role in determining the outcome of HBV infection. The opening questions include which human genes are important in infection and how to find them. Though a number of studies have sought genetic associations between HBV infection/persistence and gene polymorphisms, the candidate gene-based approach is clearly inadequate to fully explain the genetic basis of the disease. With the advent of new genetic markers and automated genotyping, genetic mapping can be conducted extremely rapid. This approach has been successful in some infectious diseases. Linkage analysis can find host genes susceptible to HBV and is of great clinical importance.

  13. Fracture risk in hepatitis C virus infected persons

    DEFF Research Database (Denmark)

    Eg Hansen, Ann-Brit; Haukali Omland, Lars; Krarup, Henrik;

    2014-01-01

    BACKGROUND & AIMS: The association between Hepatitis C virus (HCV)-infection and fracture risk is not well characterized. We compared fracture risk between HCV-seropositive (HCV-exposed) patients and the general population and between patients with cleared and chronic HCV-infection. METHODS......: Outcome measures were time to first fracture at any site, time to first low-energy and first non-low-energy (other) fracture in 12,013 HCV-exposed patients from the DANVIR cohort compared with a general population control cohort (n=60,065) matched by sex and age. Within DANVIR, 4500 patients with chronic...... HCV-infection and 2656 patients with cleared HCV-infection were studied. RESULTS: Compared with population controls, HCV-exposed patients had increased overall risk of fracture [adjusted incidence rate ratio (aIRR) 2.15, 95% Confidence Interval (CI) 2.03-2.28], increased risk of low-energy fracture (a...

  14. Angelica Sinensis May Provide Protection Against Human Immunodeficiency Virus Infection

    Directory of Open Access Journals (Sweden)

    mohammad Zarenezhad

    2008-05-01

    Full Text Available Increased oxidative stress and disturbed glutathione redox system play an important role in the pathogenesis of human immunodeficiency virus (HIV infection. Depletion in intracellular levels of reduced glutathione (GSH contributes to an increment in tumor necrosis factor α (TNF-α-stimulated-HIV-1-transcription, activation of HIV-1-replication, sensitivity to TNF-α-induced cell death, and impairment of CD4+ cell function and survival. Therefore, several studies have investigated the effect of GSH-enhancer agents such as N-acetyl cystein in the treatment of patients with HIV infection. With regard to the beneficial effects of Angelica sinensis, a Chinese medicinal herb, on GSH redox system and the pathogenic role of GSH depletion in HIV infection and the immunomodulator effects of active ingredients of this herb, we postulated that Angelica sinensis may be of value in the treatment of HIV-infected patients.

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

    Science.gov (United States)

    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.

  16. Co-infections with hepatitis B and C viruses in human immunodeficiency virus-infected patients in Morocco.

    Science.gov (United States)

    Rebbani, K; Ouladlahsen, A; Bensghir, A; Akil, A; Lamdini, H; Issouf, H; Brahim, I; Kitab, B; Fakhir, F Z; Wakrim, L; Marhoum El Filali, K; Himmich, H; Ezzikouri, S; Benjelloun, S

    2013-10-01

    Human immunodeficiency virus (HIV), hepatitis B virus (HBV) and hepatitis C virus (HCV) are major public health concerns. We aimed to determine the prevalence of HBV and HCV infections among HIV-infected patients, and to identify the main circulating hepatitis strains in Morocco. The study was carried out in 503 HIV-infected patients. Our survey indicated that the prevalence of HIV/hepatitis co-infection was 10.6%; 5.2% of patients were HBV surface antigen positive, and 5.4% of patients were anti-HCV positive. Among the HBV surface antigen-positive group, HBV DNA sequencing identified exclusively genotype D (D1: 26.7%; D7: 73.3%) in accordance with what is found in the general population. In contrast, sequencing of HCV isolates produced an unusual subtype distribution with a decreasing order of prevalence: 1a, 3a (both 23.5%), 1b, 4a (both 17.6%), 1c (11.8%) and 6h (6%).

  17. Predicted pattern of Zika virus infection distribution with reference to rainfall in Thailand.

    Science.gov (United States)

    Wiwanitkit, Somsri; Wiwanitkit, Viroj

    2016-07-01

    Zika virus infection is the present global medical problem. The disease appears in several countries around the world. The relationship between rainfall and occurrence of Zika virus infection was previously mentioned. Here, the authors use the mathematical modeling technique to reappraise on the previous data on immunoreactivity rate of Zika virus, dengue virus and Ckikungunya virus in Thailand and the reported interrelationship between arboviral infections and rainfall in Thailand for constructing of the predicted pattern of Zika virus distribution in Thailand. This data can be a useful tool for further disease surveillance in this area.

  18. Gamma interferon augments Fc gamma receptor-mediated dengue virus infection of human monocytic cells.

    OpenAIRE

    Kontny, U.; Kurane, I; Ennis, F A

    1988-01-01

    It has been reported that anti-dengue antibodies at subneutralizing concentrations augment dengue virus infection of monocytic cells. This is due to the increased uptake of dengue virus in the form of virus-antibody complexes by cells via Fc gamma receptors. We analyzed the effects of recombinant human gamma interferon (rIFN-gamma) on dengue virus infection of human monocytic cells. U937 cells, a human monocytic cell line, were infected with dengue virus in the form of virus-antibody complexe...

  19. Glomerular Diseases Associated with Hepatitis C Virus Infection

    Directory of Open Access Journals (Sweden)

    Miller Sara

    2000-01-01

    Full Text Available Renal diseases associated with hepatitis C virus (HCV infection are a significant problem for clinicians and diagnostic pathologists. A wide variety of disorders, including a spectrum of immune-complex glomerulonephritides, has been reported in association with hepatitis and cirrhosis caused by HCV. For some of these diseases, including membranoproliferative glomerulonephritis type I and cryoglobulinemic glomerulonephritis, plausible links between HCV and the glomerular pathology have been proposed. In other cases, the role of the virus in the pathogenesis of the renal disease is less certain. This communication catalogues the renal manifestations of HCV infection, providing clinical and pathological descriptions of the most prevalent disorders. Where available, evidence implicating HCV in the causation of the disorders is also discussed.

  20. Multiplex PCR for identification of herpes virus infections in adolescents.

    Science.gov (United States)

    Durzyńska, Julia; Pacholska-Bogalska, Joanna; Kaczmarek, Maria; Hanć, Tomasz; Durda, Magdalena; Skrzypczak, Magdalena; Goździcka-Józefiak, Anna

    2011-02-01

    The aim of the study was to develop a multiplex PCR (mPCR) for a rapid and simultaneous detection of herpes simplex 1 (HSV-1), herpes simplex 2 (HSV-2), and human cytomegalovirus (HCMV) DNA in squamous oral cells obtained from adolescents. Accuracy of the method was tested in a group of 513 adolescents, almost 11% of subjects were positive for infection with herpes viruses. Correlations with gender, age, and place of residence were sought. A similar incidence of HSV-2 and HCMV was found (4.3% and 5.4%, respectively) and the incidence of HSV-1 was the lowest (1%) in the study group. Conversely to HSV-2, HCMV was detected mostly in the youngest individuals. The same occurrence of all viruses was observed in boys and girls. The mPCR method described is suggested as a useful tool for epidemiologic studies of active herpes infections.

  1. In vivo models of hepatitis B and C virus infection.

    Science.gov (United States)

    Winer, Benjamin Y; Ding, Qiang; Gaska, Jenna M; Ploss, Alexander

    2016-07-01

    Globally, more than 500 million individuals are chronically infected with hepatitis B (HBV), delta (HDV), and/or C (HCV) viruses, which can result in severe liver disease. Mechanistic studies of viral persistence and pathogenesis have been hampered by the scarcity of animal models. The limited species and cellular host range of HBV, HDV, and HCV, which robustly infect only humans and chimpanzees, have posed challenges for creating such animal models. In this review, we will discuss the barriers to interspecies transmission and the progress that has been made in our understanding of the HBV, HDV, and HCV life cycles. Additionally, we will highlight a variety of approaches that overcome these barriers and thus facilitate in vivo studies of these hepatotropic viruses.

  2. Stability of the gorilla microbiome despite simian immunodeficiency virus infection.

    Science.gov (United States)

    Moeller, Andrew H; Peeters, Martine; Ayouba, Ahidjo; Ngole, Eitel Mpoudi; Esteban, Amadine; Hahn, Beatrice H; Ochman, Howard

    2015-02-01

    Simian immunodeficiency viruses (SIVs) have been discovered in over 45 primate species; however, the pathogenic potential of most SIV strains remains unknown due to difficulties inherent in observing wild populations. Because those SIV infections that are pathogenic have been shown to induce changes in the host's gut microbiome, monitoring the microbiota present in faecal samples can provide a noninvasive means for studying the effects of SIV infection on the health of wild-living primates. Here, we examine the effects of SIVgor, a close relative of SIVcpz of chimpanzees and HIV-1 of humans, on the gut bacterial communities residing within wild gorillas, revealing that gorilla gut microbiomes are exceptionally robust to SIV infection. In contrast to the microbiomes of HIV-1-infected humans and SIVcpz-infected chimpanzees, SIVgor-infected gorilla microbiomes exhibit neither rises in the frequencies of opportunistic pathogens nor elevated rates of microbial turnover within individual hosts. Regardless of SIV infection status, gorilla microbiomes assort into enterotypes, one of which is compositionally analogous to those identified in humans and chimpanzees. The other gorilla enterotype appears specialized for a leaf-based diet and is enriched in environmentally derived bacterial genera. We hypothesize that the acquisition of this gorilla-specific enterotype was enabled by lowered immune system control over the composition of the microbiome. Our results indicate differences between the pathology of SIVgor and SIVcpz/HIV-1 infections, demonstrating the utility of investigating host microbial ecology as a means for studying disease in wild primates of high conservation priority.

  3. Modeling Influenza Virus Infection: A Roadmap for Influenza Research

    Directory of Open Access Journals (Sweden)

    Alessandro Boianelli

    2015-10-01

    Full Text Available Influenza A virus (IAV infection represents a global threat causing seasonal outbreaks and pandemics. Additionally, secondary bacterial infections, caused mainly by Streptococcus pneumoniae, are one of the main complications and responsible for the enhanced morbidity and mortality associated with IAV infections. In spite of the significant advances in our knowledge of IAV infections, holistic comprehension of the interplay between IAV and the host immune response (IR remains largely fragmented. During the last decade, mathematical modeling has been instrumental to explain and quantify IAV dynamics. In this paper, we review not only the state of the art of mathematical models of IAV infection but also the methodologies exploited for parameter estimation. We focus on the adaptive IR control of IAV infection and the possible mechanisms that could promote a secondary bacterial coinfection. To exemplify IAV dynamics and identifiability issues, a mathematical model to explain the interactions between adaptive IR and IAV infection is considered. Furthermore, in this paper we propose a roadmap for future influenza research. The development of a mathematical modeling framework with a secondary bacterial coinfection, immunosenescence, host genetic factors and responsiveness to vaccination will be pivotal to advance IAV infection understanding and treatment optimization.

  4. Detection of Zika Virus Infection in Thailand, 2012-2014.

    Science.gov (United States)

    Buathong, Rome; Hermann, Laura; Thaisomboonsuk, Butsaya; Rutvisuttinunt, Wiriya; Klungthong, Chonticha; Chinnawirotpisan, Piyawan; Manasatienkij, Wudtichai; Nisalak, Ananda; Fernandez, Stefan; Yoon, In-Kyu; Akrasewi, Passakorn; Plipat, Tanarak

    2015-08-01

    Zika virus (ZIKV) is an emerging mosquito-borne pathogen with reported cases in Africa, Asia, and large outbreaks in the Pacific. No autochthonous ZIKV infections have been confirmed in Thailand. However, there have been several cases reported in travelers returning from Thailand. Here we report seven cases of acute ZIKV infection in Thai residents across the country confirmed by molecular or serological testing including sequence data. These endemic cases, combined with previous reports in travelers, provide evidence that ZIKV is widespread throughout Thailand.

  5. Multiple Pyarthrosis in Human Immunodeficiency Virus-Infected Hemophiliacs

    Directory of Open Access Journals (Sweden)

    Alistair Ingram

    1994-01-01

    Full Text Available Classically, a swollen, painful joint in a patient with hemophilia has been considered to be due to a hemarthrosis until otherwise proven, and treated immediately with appropriate coagulation factor replacement. Two cases of human immunodeficiency virus (hiv-infected hemophiliacs presenting with an initial apparent hemarthrosis, complicated subsequently by numerous pyarthroses and sepsis are described. In light of the prevalence of hiv infection in the adult hemophiliac population with arthropathy, a reappraisal of the clinical caveat of immediate infusion without joint aspiration is required.

  6. Neuromyelitis optica in patients with coexisting human immunodeficiency virus infections.

    Science.gov (United States)

    Feyissa, Anteneh M; Singh, Parbhdeep; Smith, Robert G

    2013-09-01

    Two patients with known human immunodeficiency virus (HIV) infections and receiving antiretroviral treatment developed neuromyelitis optica (Devic's disease). One patient tested positive for serum aquaporin-4 immunoglobulin G antibodies. Both patients were treated with high dose pulsed intravenous methylprednisolone followed by standard sessions of plasma exchange both at the onset attack and during disease relapses. For maintenance therapy, one patient received rituximab infusions and the second patient received mycophenolate mofetil orally. Despite treatment, both patients are currently wheelchair-bound due to severe paraparesis. Neuromyelitis optica can occur in the course of HIV infection and poses an ongoing therapeutic challenge.

  7. Occult hepatitis C virus infection in Iranian hemodialysis patients

    OpenAIRE

    Eslamifar, Ali; Ramezani, Amitis; Ehteram, Hassan; Razeghi, Effat; Ahmadi, Farrokhlagha; Amini, Manouchehr; Banifazl, Mohammad; Etemadi, Gelavizh; Keyvani, Hossein; Bavand, Anahita; Aghakhani, Arezoo

    2015-01-01

    Background: Occult hepatitis C virus (HCV) infection is defined as the presence of HCV-RNA in liver or peripheral blood mononuclear cells (PBMCs) in the absence of detectable hepatitis C antibody (anti-HCV) or HCV-RNA in the serum. Low concentrations of HCV-RNA may be detected in PBMCs of hemodialysis (HD) patients and this could have a great impact on the management of HD patients. Objectives: The aim of this study was to detect the occult HCV infection in Iranian HD patients. Patients and M...

  8. Innate immune responses in hepatitis C virus infection.

    Science.gov (United States)

    Li, Kui; Lemon, Stanley M

    2013-01-01

    Hepatitis C virus (HCV) is a major causative agent of chronic hepatitis and hepatocellular carcinoma worldwide and thus poses a significant public health threat. A hallmark of HCV infection is the extraordinary ability of the virus to persist in a majority of infected people. Innate immune responses represent the front line of defense of the human body against HCV immediately after infection. They also play a crucial role in orchestrating subsequent HCV-specific adaptive immunity that is pivotal for viral clearance. Accumulating evidence suggests that the host has evolved multifaceted innate immune mechanisms to sense HCV infection and elicit defense responses, while HCV has developed elaborate strategies to circumvent many of these. Defining the interplay of HCV with host innate immunity reveals mechanistic insights into hepatitis C pathogenesis and informs approaches to therapy. In this review, we summarize recent advances in understanding innate immune responses to HCV infection, focusing on induction and effector mechanisms of the interferon antiviral response as well as the evasion strategies of HCV.

  9. Does Zika virus infection affect mosquito response to repellents?

    Science.gov (United States)

    Leal, Walter S.; Barbosa, Rosângela M. R.; Zeng, Fangfang; Faierstein, Gabriel B.; Tan, Kaiming; Paiva, Marcelo H. S.; Guedes, Duschinka R. D.; Crespo, Mônica M.; Ayres, Constância F. J.

    2017-01-01

    The World Health Organization (WHO) recommends that people travelling to or living in areas with Zika virus (ZIKV) outbreaks or epidemics adopt prophylactic measures to reduce or eliminate mosquito bites, including the use of insect repellents. It is, however, unknown whether repellents are effective against ZIKV-infected mosquitoes, in part because of the ethical concerns related to exposing a human subject’s arm to infected mosquitoes in the standard arm-in-cage assay. We used a previously developed, human subject-free behavioural assay, which mimics a human subject to evaluate the top two recommended insect repellents. Our measurements showed that DEET provided significantly higher protection than picaridin provided against noninfected, host-seeking females of the southern house mosquito, Culex quinquefasciatus, and the yellow fever mosquito, Aedes aegypti. When tested at lower doses, we observed a significant reduction in DEET-elicited protection against ZIKV-infected yellow fever mosquitoes from old and recent laboratory colonies. The reduction in protection is more likely associated with aging than the virus infection and could be compensated by applying a 5x higher dose of DEET. A substantial protection against ZIKV-infected and old noninfected mosquitoes was achieved with 5% DEET, which corresponds approximately to a 30% dose in the conventional arm-in-cage assays. PMID:28205633

  10. Zika Virus Infection in Pregnant Women in Rio de Janeiro.

    Science.gov (United States)

    Brasil, Patrícia; Pereira, José P; Moreira, M Elisabeth; Ribeiro Nogueira, Rita M; Damasceno, Luana; Wakimoto, Mayumi; Rabello, Renata S; Valderramos, Stephanie G; Halai, Umme-Aiman; Salles, Tania S; Zin, Andrea A; Horovitz, Dafne; Daltro, Pedro; Boechat, Marcia; Raja Gabaglia, Claudia; Carvalho de Sequeira, Patrícia; Pilotto, José H; Medialdea-Carrera, Raquel; Cotrim da Cunha, Denise; Abreu de Carvalho, Liege M; Pone, Marcos; Machado Siqueira, André; Calvet, Guilherme A; Rodrigues Baião, Ana E; Neves, Elizabeth S; Nassar de Carvalho, Paulo R; Hasue, Renata H; Marschik, Peter B; Einspieler, Christa; Janzen, Carla; Cherry, James D; Bispo de Filippis, Ana M; Nielsen-Saines, Karin

    2016-12-15

    Background Zika virus (ZIKV) has been linked to central nervous system malformations in fetuses. To characterize the spectrum of ZIKV disease in pregnant women and infants, we followed patients in Rio de Janeiro to describe clinical manifestations in mothers and repercussions of acute ZIKV infection in infants. Methods We enrolled pregnant women in whom a rash had developed within the previous 5 days and tested blood and urine specimens for ZIKV by reverse-transcriptase-polymerase-chain-reaction assays. We followed women prospectively to obtain data on pregnancy and infant outcomes. Results A total of 345 women were enrolled from September 2015 through May 2016; of these, 182 women (53%) tested positive for ZIKV in blood, urine, or both. The timing of acute ZIKV infection ranged from 6 to 39 weeks of gestation. Predominant maternal clinical features included a pruritic descending macular or maculopapular rash, arthralgias, conjunctival injection, and headache; 27% had fever (short-term and low-grade). By July 2016, a total of 134 ZIKV-affected pregnancies and 73 ZIKV-unaffected pregnancies had reached completion, with outcomes known for 125 ZIKV-affected and 61 ZIKV-unaffected pregnancies. Infection with chikungunya virus was identified in 42% of women without ZIKV infection versus 3% of women with ZIKV infection (PBrasil and others.).

  11. Hepatitis A virus infection: Epidemiology and genetic diversity

    Directory of Open Access Journals (Sweden)

    Báez Triana, Paula Andrea

    2015-04-01

    Full Text Available Hepatitis A virus infection is a global public health problem. The virus has a wide range of distribution and it is the main cause of acute hepatitis transmitted by the enteric route in Latin America. The viral particle is stable under environmental conditions and conserves its infectivity for several weeks, enabling its transmission by contaminated water and food. Worldwide, different epidemiological patterns have been identified, which may change over time by modification of social and economic variables in the population such as vaccination and the improvement of hygiene and primary health conditions. This leaves new populations susceptible to infection. In Latin America the circulation of genotype I and subgenotypes A and B has been described, but more research is needed to provide the knowledge needed to manage the prevention and control plans for the worldwide reduction of the prevalence of infection. For this paper, a literature review was performed on the SciELO, PubMed and ScienceDirect databases under the search terms "Hepatitis A", "Epidemiology," "Seroprevalence" and "Infection." From the results obtained, only papers published in English and Spanish to describe epidemiological and molecular studies of interest in Latin America were included.

  12. Evidence of Apis cerana Sacbrood virus Infection in Apis mellifera.

    Science.gov (United States)

    Gong, Hong-Ri; Chen, Xiu-Xian; Chen, Yan Ping; Hu, Fu-Liang; Zhang, Jiang-Lin; Lin, Zhe-Guang; Yu, Ji-Wei; Zheng, Huo-Qing

    2016-04-01

    Sacbrood virus(SBV) is one of the most destructive viruses in the Asian honeybee Apis cerana but is much less destructive in Apis mellifera In previous studies, SBV isolates infecting A. cerana(AcSBV) and SBV isolates infecting A. mellifera(AmSBV) were identified as different serotypes, suggesting a species barrier in SBV infection. In order to investigate this species isolation, we examined the presence of SBV infection in 318A. mellifera colonies and 64A. cerana colonies, and we identified the genotypes of SBV isolates. We also performed artificial infection experiments under both laboratory and field conditions. The results showed that 38A. mellifera colonies and 37A. cerana colonies were positive for SBV infection. Phylogenetic analysis based on RNA-dependent RNA polymerase (RdRp) gene sequences indicated that A. cerana isolates and most A. mellifera isolates formed two distinct clades but two strains isolated fromA. mellifera were clustered with theA. cerana isolates. In the artificial-infection experiments, AcSBV negative-strand RNA could be detected in both adult bees and larvae ofA. mellifera, although there were no obvious signs of the disease, demonstrating the replication of AcSBV inA. mellifera Our results suggest that AcSBV is able to infectA. melliferacolonies with low prevalence (0.63% in this study) and pathogenicity. This work will help explain the different susceptibilities ofA. cerana and A. melliferato sacbrood disease and is potentially useful for guiding beekeeping practices.

  13. Regional Aggressive Root Resorption Caused by Neuronal Virus Infection

    Directory of Open Access Journals (Sweden)

    Inger Kjær

    2012-01-01

    Full Text Available During orthodontic treatment, root resorption can occur unexplainably. No clear distinction has been made between resorption located within specific regions and resorption occurring generally in the dentition. The purpose is to present cases with idiopathic (of unknown origin root resorption occurring regionally. Two cases of female patients, 26 and 28 years old, referred with aggressive root resorption were investigated clinically and radiographically. Anamnestic information revealed severe virus diseases during childhood, meningitis in one case and whooping cough in the other. One of the patients was treated with dental implants. Virus spreading along nerve paths is a possible explanation for the unexpected resorptions. In both cases, the resorptions began cervically. The extent of the resorption processes in the dentition followed the virus infected nerve paths and the resorption process stopped when reaching regions that were innervated differently and not infected by virus. In one case, histological examination revealed multinuclear dentinoclasts. The pattern of resorption in the two cases indicates that innervation is a factor, which under normal conditions may protect the root surface against resorption. Therefore, the normal nerve pattern is important for diagnostics and for predicting the course of severe unexpected root resorption.

  14. Experimental infection of house sparrows (Passer domesticus) with Rocio virus.

    Science.gov (United States)

    Monath, T P; Kemp, G E; Cropp, C B; Bowen, G S

    1978-11-01

    Rocio encephalitis is a new epidemic flaviviral infection of man, first described in São Paulo State, Brazil in 1975. The ecology of the viral transmission cycle remains largely unknown. Experimental studies were undertaken to assess the role of a wild avian species, the House Sparrow, as a maintenance or amplifying host. Approximately two-thirds of nesting and adult sparrows developed 2- to 3-day viremias of low to moderate magnitude (2.0--4.3 log/ml). Rocio-immune birds were not protected against challenge with St. Louis encephalitis (SLE) virus, but prior SLE viral infection prevented detectable viremia in birds challenged with Rocio virus. These studies provide some support for the hypothesis that birds are hosts for Rocio virus, but the House Sparrow probably plays a relatively minor role in viral transmission. Because sparrows are relatively inefficient viremic hosts, they would be expected to play a minor role in transmission should Rocio virus be introduced into the United States.

  15. Dynamic stochastic simulation as a tool for studying bovine virus diarrhoea virus infections at the herd level

    DEFF Research Database (Denmark)

    Sørensen, J.T.; Enevoldsen, Carsten

    1994-01-01

    Infectious diseases, such as bovine virus diarrhoea (BVD) virus infections in cattle, are often studied by Markov chain models. However, it is difficult to simulate dynamic interactions between production of a reproductive herd and the disease by this type of model. As an alternative, a dynamic...... stochastic model simulating the herd production was suggested. A dynamic stochastic model simulating the effect of BVD virus infection in a dairy cattle herd was used to exemplify how this type of model could be applied in research. The simulation example demonstrated that the effect of a BVD virus infection...

  16. Non-coding RNAs and heme oxygenase-1 in vaccinia virus infection

    Science.gov (United States)

    Meseda, Clement A.; Srinivasan, Kumar; Wise, Jasen; Catalano, Jennifer; Yamada, Kenneth M.; Dhawan, Subhash

    2017-01-01

    Small nuclear RNAs (snRNAs) are undetermined, a population of snRNAs is produced during the early phase of infection of cells by vaccinia virus. In the present study, we demonstrate a direct correlation between expression of the cytoprotective enzyme heme oxygenase-1 (HO-1), suppression of selective snRNA expression, and inhibition of vaccinia virus infection of macrophages. Hemin induced HO-1 expression, completely reversed virus-induced host snRNA expression, and suppressed vaccinia virus infection. This involvement of specific virus-induced snRNAs and associated gene clusters suggests a novel HO-1-dependent host-defense pathway in poxvirus infection. PMID:25450361

  17. Occult Hepatitis C Virus Infection among Hemodialysis Patients

    OpenAIRE

    G. Barril; Castillo, I.; Arenas, M.D. (María Dolores); Espinosa, M; Garcia-Valdecasas, J. (Juan); Garcia-Fernandez, N. (Nuria); E Gonzalez-Parra; Alcazar, J.M. (José María); Sanchez, C.; Diez-Baylon, J.C. (José Carlos); P. MARTINEZ; Bartolome, J; Carreño, V

    2008-01-01

    Occult hepatitis C virus (HCV) infection (i.e., detectable HCV-RNA in the liver or peripheral blood mononuclear cells) in the absence of both serum HCV-RNA and anti-HCV antibodies has not been investigated in hemodialysis patients. In this study, real-time PCR and in situ hybridization was used to test for the presence of genomic and antigenomic HCV-RNA in peripheral blood mononuclear cells of 109 hemodialysis patients with abnormal levels of live...

  18. Viral DNA in horses infected with equine infectious anemia virus.

    OpenAIRE

    Rice, N R; Lequarré, Anne-Sophie; Casey, J W; Lahn, S; Stephens, R. M.; Edwards, J.

    1989-01-01

    The amount and distribution of viral DNA were established in a horse acutely infected with the Wyoming strain of equine infectious anemia virus (EIAV). The highest concentration of viral DNA were found in the liver, lymph nodes, bone marrow, and spleen. The kidney, choroid plexus, and peripheral blood leukocytes also contained viral DNA, but at a lower level. It is estimated that at day 16 postinoculation, almost all of the viral DNA was located in the tissues, with the liver alone containing...

  19. Transgenic tomato hybrids resistant to tomato spotted wilt virus infection.

    OpenAIRE

    Haan, de, A.; Ultzen, T.; Prins, M.; Gielen, J; Goldbach, R; Grinsven, van, J.J.M.

    1996-01-01

    Tomato spotted wilt virus (TSWV) infections cause significant economic losses in the commercial culture of tomato (Lycopersicon esculentum). Culture practices have only been marginally effective in controlling TSWV. The ultimate way to minimize losses caused by TSWV is resistant varieties. These can be obtained by introgression of natural sources of resistance from wild relatives or by expressing viral sequences in transgenic tomato plants. We report high levels of resistance to TSWV obtained...

  20. Longitudinal study on oral shedding of herpes simplex virus 1 and varicella-zoster virus in individuals infected with HIV

    NARCIS (Netherlands)

    M. van Velzen (Monique); W.J.D. Ouwendijk (Werner ); S. Selke (Stacy); S.D. Pas (Suzan); F.B. van Loenen (Freek); A.D.M.E. Osterhaus (Albert); A. Wald (Anna); G.M.G.M. Verjans (George)

    2013-01-01

    textabstractPrimary herpes simplex virus 1 (HSV-1) and varicella-zoster virus (VZV) infection leads to a life-long latent infection of ganglia innervating the oral mucosa. HSV-1 and VZV reactivation is more common in immunocompromised individuals and may result in viral shedding in saliva. We determ

  1. Gene expression responses to highly pathogenic avian influenza H5N1 virus infections in ducks

    Science.gov (United States)

    Differences in host response to infection with avian influenza (AI) viruses were investigated by identifying genes differentially expressed in tissues of infected ducks. Clear differences in pathogenicity were observed among ducks inoculated with five H5N1 HPAI viruses. Virus titers in tissues cor...

  2. Blood Feeding Behavior of Vesicular Stomatitis Virus Infected Culicoides Sonorensis (Diptera: Ceratopogonidae)

    Science.gov (United States)

    To determine whether vesicular stomatitis virus (VSV) infection of Culicoides sonorensis affects subsequent blood feeding behavior, midges injected with either virus-infected or virus-free cell lysates were allowed to blood feed for short (10 min) or long (60 min) periods of time on days 2, 3, and 4...

  3. A dual drug regimen synergistically blocks human parainfluenza virus infection

    Science.gov (United States)

    Bailly, Benjamin; Dirr, Larissa; El-Deeb, Ibrahim M.; Altmeyer, Ralf; Guillon, Patrice; von Itzstein, Mark

    2016-04-01

    Human parainfluenza type-3 virus (hPIV-3) is one of the principal aetiological agents of acute respiratory illness in infants worldwide and also shows high disease severity in the elderly and immunocompromised, but neither therapies nor vaccines are available to treat or prevent infection, respectively. Using a multidisciplinary approach we report herein that the approved drug suramin acts as a non-competitive in vitro inhibitor of the hPIV-3 haemagglutinin-neuraminidase (HN). Furthermore, the drug inhibits viral replication in mammalian epithelial cells with an IC50 of 30 μM, when applied post-adsorption. Significantly, we show in cell-based drug-combination studies using virus infection blockade assays, that suramin acts synergistically with the anti-influenza virus drug zanamivir. Our data suggests that lower concentrations of both drugs can be used to yield high levels of inhibition. Finally, using NMR spectroscopy and in silico docking simulations we confirmed that suramin binds HN simultaneously with zanamivir. This binding event occurs most likely in the vicinity of the protein primary binding site, resulting in an enhancement of the inhibitory potential of the N-acetylneuraminic acid-based inhibitor. This study offers a potentially exciting avenue for the treatment of parainfluenza infection by a combinatorial repurposing approach of well-established approved drugs.

  4. [Zika virus infection or the future of infectious diseases].

    Science.gov (United States)

    Valerio Sallent, Lluís; Roure Díez, Sílvia; Fernández Rivas, Gema

    2016-10-07

    Zika virus belongs to the Flaviridae, an extended phylogenetic family containing dengue or yellow fever, viruses whose shared main vector are Aedes aegypti mosquitoes. The virus originally came from Central African simian reservoirs and, from there, expanded rapidly across the Pacific to South America. The disease is an example of exantematic fever usually mild. Mortality is very low and mainly limited to secondary Guillain-Barré or fetal microcephaly cases. Diagnostic confirmation requires a RT-PCR in blood up to the 5th day from the onset or in urine up to the 10-14th day. Specific IgM are identifiable from the 5th symptomatic day. Clinically, a suspected case should comply with: a) a journey to epidemic areas; b) a clinically compatible appearance with fever and skin rash, and c) a generally normal blood count/basic biochemistry. There is some evidence that causally relates Zika virus infection with fetal microcephaly. While waiting for definitive data, all pregnant women coming from Central or South America should be tested for Zika virus.

  5. [Hepatitis C virus infection in hemodialysis].

    Science.gov (United States)

    Simon, N

    1995-10-01

    The surveillance of HCV infections is now a must in the clinical management of hemodialysis patients. The natural history of HCV has shown acute hepatitis to be a constant feature although rarely symptomatic. Progression to chronicity occurs in 90% of the cases with detectable viremia in 80% of the cases. The long-term impact of the liver disease in chronic hemodialyzed patients remains to be defined. HCV is responsible for more than 90% of the non-A, non-B hepatitis case diagnosed among hemodialyzed patients. The transmission is either transfusional or nosocomial. Following recent transfusion safety regulations, the nosocomial risk became the predominant residual risk. Thus, all efforts should target HCV eradication. In the absence of specific prophylaxis, this can only be achieved by enforcement of very stringent precautions.

  6. Medical management of human immunodeficiency virus infection

    Directory of Open Access Journals (Sweden)

    Kempen John

    2008-01-01

    Full Text Available The human immunodeficiency virus (HIV/ acquired immune deficiency syndrome (AIDS pandemic has pervasive effects on culture, economics, policy, and human development. All organs can be affected by complications of HIV/AIDS, including the eye. When sufficient resources are available and widespread antiretroviral resistance does not exist, the four available classes of antiretroviral agents - nucleoside/nucleotide reverse transcriptase inhibitors, non-nucleoside reverse transcriptase inhibitors, protease inhibitors, and fusion inhibitors - can be combined to provide highly active antiretroviral therapy (HAART. For many (not all patients, HAART converts an inexorably fatal disease into a chronic disease with a fairly good prognosis. Use of HAART often induces partial immune recovery, which has predominantly beneficial effects on ocular complications of AIDS. However, HAART-induced immune recovery sometimes results in immune recovery inflammatory syndromes, such as immune recovery uveitis. Use of HAART is the single most useful intervention for most patients with ocular complications of AIDS. However, specific ocular therapy is also critical to avoid blindness in the early months before immune recovery can occur, or if HAART is unavailable. Increasing availability of HAART worldwide shows great promise to alleviate one of the world′s greatest plagues. However, predictable secular trends in the AIDS epidemic make it likely that the number of cases of ocular complications of AIDS will increase substantially before they decrease. Ophthalmologists worldwide should be familiar with the diagnosis and management of cytomegalovirus retinitis - the most common ocular complication of AIDS - and should establish partnerships with physicians who are able to provide HAART. Research is needed to determine the optimal approach for managing cytomegalovirus retinitis in resource-constrained settings.

  7. Prior infection of pigs with swine influenza viruses is a barrier to infection with avian influenza viruses.

    Science.gov (United States)

    De Vleeschauwer, Annebel; Van Reeth, Kristien

    2010-12-15

    Although pigs are susceptible to avian influenza viruses (AIV) of different subtypes, the incidence of AIV infections in the field appears to be low. Swine H1N1, H3N2 and H1N2 influenza viruses (SIV) are enzootic worldwide and most pigs have antibodies to 1 or more SIV subtypes. This study aimed to examine whether infection-immunity to H1N1 or H3N2 SIV may (1) protect pigs against subsequent infections with AIV of various haemagglutinin and/or neuraminidase subtypes and/or (2) interfere with the serological diagnosis of AIV infection by haemagglutination inhibition (HI) or virus neutralization (VN) tests. Pigs were inoculated intranasally with an H1N1 or H3N2 SIV or left uninoculated. Four or 6 weeks later all pigs were challenged intranasally with 1 of 3 AIV subtypes (H4N6, H5N2 or H7N1). Fifteen out of 17 challenge control pigs shed the respective AIV for 4-6 days post-inoculation and 16 developed HI and VN antibodies. In contrast, 28 of the 29 SIV-immune pigs did not have detectable AIV shedding. Only 12 SIV-immune pigs developed HI antibodies to the AIV used for challenge and 14 had VN antibodies. Antibody titres to the AIV were low in both control and SIV-immune pigs. Our data show that prior infection of pigs with SIV is a barrier to infection with AIV of unrelated subtypes. Serological screening in regions where SIV is enzootic is only useful when the AIV strain for which the pigs need to be tested is known.

  8. Piroxicam inhibits herpes simplex virus type 1 infection in vitro.

    Science.gov (United States)

    Astani, A; Albrecht, U; Schnitzler, P

    2015-05-01

    Piroxicam is a potent, nonsteroidal, anti-inflammatory agent (NSAID) which also exhibits antipyretic activity. The antiviral effect of piroxicam against herpes simplex virus type 1 (HSV-1) was examined in vitro on RC-37 monkey kidney cells using a plaque reduction assay. Piroxicam was dissolved in ethanol or dimethylsulfoxide (DMSO) and the 50% inhibitory concentration (IC50) was determined at 4 μg/ml and 75 μg/ml, respectively. The IC50 for the standard antiherpetic drug acyclovir was determined at 1.6 μM. At non-cytotoxic concentrations of these piroxicam solutions, plaque formation was significantly reduced by 62.4% for ethanolic piroxicam and 72.8% for piroxicam in DMSO. The mode of antiviral action of these drugs was assessed by time-on-addition assays. No antiviral effect was observed when cells were incubated with piroxicam prior to infection with HSV-1 or when HSV-1 infected cells were treated with dissolved piroxicam. Herpesvirus infection was, however, significantly inhibited when HSV-1 was incubated with piroxicam prior to the infection of cells. These results indicate that piroxicam affected the virus before adsorption, but not after penetration into the host cell, suggesting that piroxicam exerts a direct antiviral effect on HSV-1. Free herpesvirus was sensitive to piroxicam in a concentration-dependent manner and the inhibition of HSV-1 appears to occur before entering the cell but not after penetration of the virus into the cell. Considering the lipophilic nature of piroxicam, which enables it to penetrate the skin, it might be suitable for topical treatment of herpetic infections.

  9. Hepatitis B Virus Infection and Immunizations among Asian American College Students: Infection, Exposure, and Immunity Rates

    Science.gov (United States)

    Lee, Haeok; Kiang, Peter; Watanabe, Paul; Halon, Patricia; Shi, Ling; Church, Daniel R.

    2013-01-01

    Objectives: To evaluate the prevalence of hepatitis B virus (HBV) infection, exposure, and immunity among Asian American college students as a basis for evaluating HBV screening and vaccination policy. Participants and Methods: Self-identified Asian American college students aged 18 years or older were examined. Serological tests of HBV surface…

  10. The course of hepatitis E virus infection in pigs after contact-infection and intravenous inoculation

    NARCIS (Netherlands)

    Bouwknegt, M.; Rutjes, S.A.; Reusken, C.B.E.M.; Stockhofe-Zurwieden, N.; Frankena, K.; Jong, de M.C.M.; Roda Husman, de A.M.; Poel, van der W.H.M.

    2009-01-01

    Background - Worldwide, hepatitis E virus (HEV) genotype 3 is observed in pigs and transmission to humans is implied. To be able to estimate public health risks from e.g. contact with pigs or consumption of pork products, the transmission routes and dynamics of infection should be identified. Hence,

  11. Effect of tobacco mosaic virus infection on host and virus-specific protein synthesis in protoplasts

    Energy Technology Data Exchange (ETDEWEB)

    Siegel, A.; Hari, V.; Kolacz, K.

    1978-04-01

    The nature and rate of virus-specific protein synthesis were determined in tobacco mosaic virus-infected protoplasts as a function of time after inoculation. Samples of infected and mock-infected protoplasts were exposed to radioactive amino acid for relatively short sequential time periods and the consequent labeled proteins were assessed following SDS-polyacrylamide gel electrophoresis and fluorography. The synthesis of three virus-specific proteins of molecular weights 160,000, 135,000, and 17,500 was confirmed. Synthesis of all three proteins was first detected during the 5- to 7-hr postinoculation period at which time the synthetic rate of the 135,000-dalton protein was greatest.This was soon overtaken by the 17,500-dalton capsid protein, the synthetic rate of which kept increasing until it accounted for a major portion of total protoplast protein synthesis. At 1 day postinoculation, it accounted for 50% and, at not quite 2 days, 70% of the total protein synthesis. Evidence is presented to suggest that virus-specific protein synthesis occurs in addition to, rather than at the expense of, normal cellular protein synthesis.

  12. White spot syndrome virus envelope protein VP124 involved in the virus infection

    Institute of Scientific and Technical Information of China (English)

    ZHU Yanbing; WU Chenglin; YANG Feng

    2008-01-01

    White spot syndrome virus(WSSV)is one of the major shrimp pathogens causing large economic losses to shrimp farming.In an attempt to identify the envelope proteins involved in the virus infection,purified WSSV virions were mixed with three antisera against WSSV envelope proteins(VP39,VP124 and VP187),individually.And then they were injected intramuscularly into crayfish (Procambarus clarkii) to conduct in vivo neutralization assays.The results showed that for groups injected with virions only and groups injected with the mixture of virions and antiserum against VP124,the crayfish mortalities were 100% and 60% on the 8th day postinfection,individually.The virus infection could be delayed or neutralized by antibody against the envelope pro-tein VP124.Quantitative PCR was used to further investigate the influence of three antisera described above on the virus infec-tion.The results showed that the antiserum against VP124 could restrain the propagation of WSSV in crayfish.All of the results suggested that the viral envelope protein VP124 played a role in WSSV infection.

  13. Molecular characteristics and stages of chronic hepatitis B virus infection

    Institute of Scientific and Technical Information of China (English)

    Ying-Hui Shi; Chang-He Shi

    2009-01-01

    Hepatitis B virus (HBV) is a common viral pathogen that causes a substantial health burden worldwide. Remarkable progress has been made in our understanding of the natural stages of chronic HBV infection. A dynamic balance between viral replication and host immune response is pivotal to the pathogenesis of liver disease. Knowledge of the HBV genome organization and replication cycle can unravel HBV genotypes and molecular variants, which contribute to the heterogeneity in outcome of chronic HBV infection. Most HBV infections are spontaneously resolved in immunocompetent adults, whereas they become chronic in most neonates and infants at a great risk of developing complications such as cirrhosis and hepatocellular carcinoma (HCC). Those with chronic HBV infection may present in one of the four phases of infection: immune tolerance, immune clearance [hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB)], inactive carrier state, and reactivation (HBeAg-negative CHB). Understanding the dynamic nature of chronic HBV infection is crucial in the management of HBV carriers. Long-term monitoring and optimal timing of antiviral therapy for chronic HBV infection help to prevent progression of HBV-related liver disease to its later stage, particularly in patients with higher risk markers of HCC, such as serum DNA concentration, HBeAg status, serum aminotransferase, HBV genotypes, and pre-core or core mutants.

  14. Oral lesions in infection with human immunodeficiency virus.

    Science.gov (United States)

    Coogan, Maeve M.; Greenspan, John; Challacombe, Stephen J.

    2005-01-01

    This paper discusses the importance of oral lesions as indicators of infection with human immunodeficiency virus (HIV) and as predictors of progression of HIV disease to acquired immunodeficiency syndrome (AIDS). Oral manifestations are among the earliest and most important indicators of infection with HIV. Seven cardinal lesions, oral candidiasis, hairy leukoplakia, Kaposi sarcoma, linear gingival erythema, necrotizing ulcerative gingivitis, necrotizing ulcerative periodontitis and non-Hodgkin lymphoma, which are strongly associated with HIV infection, have been identified and internationally calibrated, and are seen in both developed and developing countries. They may provide a strong indication of HIV infection and be present in the majority of HIV-infected people. Antiretroviral therapy may affect the prevalence of HIV-related lesions. The presence of oral lesions can have a significant impact on health-related quality of life. Oral health is strongly associated with physical and mental health and there are significant increases in oral health needs in people with HIV infection, especially in children, and in adults particularly in relation to periodontal diseases. International collaboration is needed to ensure that oral aspects of HIV disease are taken into account in medical programmes and to integrate oral health care with the general care of the patient. It is important that all health care workers receive education and training on the relevance of oral health needs and the use of oral lesions as surrogate markers in HIV infection. PMID:16211162

  15. Human neuronal cell protein responses to Nipah virus infection

    Directory of Open Access Journals (Sweden)

    Hassan Sharifah

    2007-06-01

    Full Text Available Abstract Background Nipah virus (NiV, a recently discovered zoonotic virus infects and replicates in several human cell types. Its replication in human neuronal cells, however, is less efficient in comparison to other fully susceptible cells. In the present study, the SK-N-MC human neuronal cell protein response to NiV infection is examined using proteomic approaches. Results Method for separation of the NiV-infected human neuronal cell proteins using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE was established. At least 800 protein spots were resolved of which seven were unique, six were significantly up-regulated and eight were significantly down-regulated. Six of these altered proteins were identified using mass spectrometry (MS and confirmed using MS/MS. The heterogenous nuclear ribonucleoprotein (hnRNP F, guanine nucleotide binding protein (G protein, voltage-dependent anion channel 2 (VDAC2 and cytochrome bc1 were present in abundance in the NiV-infected SK-N-MC cells in contrast to hnRNPs H and H2 that were significantly down-regulated. Conclusion Several human neuronal cell proteins that are differentially expressed following NiV infection are identified. The proteins are associated with various cellular functions and their abundance reflects their significance in the cytopathologic responses to the infection and the regulation of NiV replication. The potential importance of the ratio of hnRNP F, and hnRNPs H and H2 in regulation of NiV replication, the association of the mitochondrial protein with the cytopathologic responses to the infection and induction of apoptosis are highlighted.

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

    Directory of Open Access Journals (Sweden)

    Héctor Moreno

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

  17. TLR3 deficiency renders astrocytes permissive to herpes simplex virus infection and facilitates establishment of CNS infection in mice

    DEFF Research Database (Denmark)

    Reinert, Line S; Harder, Louis; Holm, Christian K

    2012-01-01

    Herpes simplex viruses (HSVs) are highly prevalent neurotropic viruses. While they can replicate lytically in cells of the epithelial lineage, causing lesions on mucocutaneous surfaces, HSVs also establish latent infections in neurons, which act as reservoirs of virus for subsequent reactivation ...

  18. Hepatitis C virus infections among HIV-infected men who have sex with men: an expanding epidemic

    NARCIS (Netherlands)

    A.T. Urbanus; T.J. van de Laar; I.G. Stolte; J. Schinkel; T. Heijman; R.A. Coutinho; M. Prins

    2009-01-01

    Background: Since 2000 outbreaks of sexually transmitted hepatitis C Virus (HCV) infections have been reported among HIV-infected men who have sex with men (MSM). We studied the prevalence and determinants of HCV-infection among MSM attending a large sexually transmitted infection (STI) clinic in th

  19. Hepatitis C virus infection among transmission-prone medical personnel.

    Science.gov (United States)

    Zaaijer, H L; Appelman, P; Frijstein, G

    2012-07-01

    Hepatitis C virus (HCV)-infected physicians have been reported to infect some of their patients during exposure-prone procedures (EPPs). There is no European consensus on the policy for the prevention of this transmission. To help define an appropriate preventive policy, we determined the prevalence of HCV infection among EPP-performing medical personnel in the Academic Medical Center in Amsterdam, the Netherlands. The prevalence of HCV infection was studied among 729 EPP-performing health care workers. Serum samples, stored after post-hepatitis B virus (HBV) vaccination testing in the years 2000-2009, were tested for HCV antibodies. Repeat reactive samples were confirmed by immunoblot assay and the detection of HCV RNA. The average age of the 729 health care workers was 39 years (range 18-66), suggesting a considerable cumulative occupational exposure to the blood. Nevertheless, only one of the 729 workers (0.14%; 95% confidence interval [CI]: <0.01% to 0.85%) was tested and confirmed to be positive for anti-HCV and positive for HCV RNA, which is comparable to the prevalence of HCV among Amsterdam citizens. Against this background, for the protection of personnel and patients, careful follow-up after needlestick injuries may be sufficient. If a zero-risk approach is desirable and costs are less relevant, the recurrent screening of EPP-performing personnel for HCV is superior to the follow-up of reported occupational exposures.

  20. Chikungunya Virus Infection: An Update on Joint Manifestations and Management

    Directory of Open Access Journals (Sweden)

    Maria Krutikov

    2016-10-01

    Full Text Available The advent of sophisticated diagnostics has enabled the discovery of previously unknown arthropod-borne viruses like Chikungunya. This infection has become increasingly prevalent in the last 10 years across the Indian Ocean and has been brought to media attention by a recent outbreak in the Caribbean. The outbreak has been aided by a drastic rise in air travel, allowing infected individuals to transport the virus to previously unaffected regions. In addition, a recently documented viral mutation has allowed its transmission by the Aedes albopictus mosquito, therefore facilitating outbreaks in Southern Europe and the USA. The duration and extent of the arthritis seen peri- and post infection has become a topic of academic interest. Although published data are largely observational, there has been a definite increase in original research focusing on this. Symptoms can persist for years, particularly in older patients with pre-existing medical conditions. The etiology is still not fully understood, but viral persistence and immune activation within synovial fluid have been shown in mouse models. There have been no prospective clinical trials of treatment in humans; however, animal trials are in process. The mainstay of treatment remains anti-inflammatories and steroids where necessary. The clinical presentation seems to mimic common rheumatological conditions like rheumatoid arthritis; therefore recent recommendations suggest the use disease-modifying agents as a common practice for the specific syndrome. This review uses recent published data and draws on our own clinical experience to provide an overview of joint complications of Chikungunya infection.

  1. Cluster of Nipah virus infection, Kushtia District, Bangladesh, 2007.

    Directory of Open Access Journals (Sweden)

    Nusrat Homaira

    Full Text Available OBJECTIVE: In March 2007, we investigated a cluster of Nipah encephalitis to identify risk factors for Nipah infection in Bangladesh. METHODS: We defined confirmed Nipah cases by the presence of IgM and IgG antibodies against Nipah virus in serum. Case-patients, who resided in the same village during the outbreak period but died before serum could be collected, were classified as probable cases. RESULTS: We identified three confirmed and five probable Nipah cases. There was a single index case. Five of the secondary cases came in close physical contact to the index case when she was ill. Case-patients were more likely to have physical contact with the index case (71% cases versus 0% controls, p = <0.001. The index case, on her third day of illness, and all the subsequent cases attended the same religious gathering. For three probable cases including the index case, we could not identify any known risk factors for Nipah infection such as physical contact with Nipah case-patients, consumption of raw date palm juice, or contact with sick animals or fruit bats. CONCLUSION: Though person-to-person transmission remains an important mode of transmission for Nipah infection, we could not confirm the source of infection for three of the probable Nipah case-patients. Continued surveillance and outbreak investigations will help better understand the transmission of Nipah virus and develop preventive strategies.

  2. Pathogenesis of occult chronic hepatitis B virus infection

    Institute of Scientific and Technical Information of China (English)

    Rocio Aller de la Fuente; María L Gutiérrez; Javier Garcia-Samaniego; Conrado Fernández-Rodriguez; Jose Luis Lledó; Gregorio Castellano

    2011-01-01

    Occult hepatitis B infection (OBI) is characterized by hepatitis B virus (HBV) DNA in serum in the absence of hepatitis B surface antigen (HBsAg) presenting HBsAg-negative and anti-HBc positive serological patterns. Occult HBV status is associated in some cases with mutant viruses undetectable by HBsAg assays; but more frequently it is due to a strong suppression of viral replication and gene expression. OBI is an entity with world-wide diffusion. The failure to detect HBsAg, despite the persistence of the viral DNA, is due in most cases to the strong suppression of viral replication and gene expression that characterizes this "occult" HBV infection; although the mechanisms responsible for suppression of HBV are not well understood. The majority of OBI cases are secondary to overt HBV infection and represent a residual low viremia level suppressed by a strong immune response together with histological derangements which occurred during acute or chronic HBV infection. Much evidence suggests that it can favour the progression of liver fibrosis and the development of hepatocellular carcinoma.

  3. Phospholipid Synthesis in Sindbis Virus-Infected Cells

    Science.gov (United States)

    Waite, Marilynn R. F.; Pfefferkorn, E. R.

    1970-01-01

    We investigated the metabolic requirements for the decrease in phospholipid synthesis previously observed by Pfefferkorn and Hunter in primary cultures of chick embryo fibroblasts infected with Sindbis virus. The incorporation of 32PO4 into all classes of phospholipids was found to decline at the same rate and to the same extent; thus, incorporation of 14C-choline into acid-precipitable form provided a convenient measure of phospholipid synthesis that was used in subsequent experiments. Experiments with temperature-sensitive mutants suggested that some viral ribonucleic acid (RNA) synthesis was essential for the inhibition of choline incorporation, but that functional viral structural proteins were not required. The reduction in phospholipid synthesis was probably a secondary effect of infection resulting from viral inhibition of the cellular RNA and protein synthesis. All three inhibitory effects required about the same amount of viral RNA synthesis; the inhibition of host RNA and protein synthesis began sooner than the decline in phospholipid synthesis; and both actinomycin D and cycloheximide inhibited 14C-choline incorporation in uninfected cells. In contrast, incorporation of 14C-choline into BHK-21 cells was not decreased by 10 hr of exposure to actinomycin D and declined only slowly after cycloheximide treatment. Growth of Sindbis virus in BHK cells did not cause the marked stimulation of phospholipid synthesis seen in picornavirus infections of other mammalian cells; however, inhibition was seen only late in infection. PMID:5530011

  4. Host immune status and response to hepatitis E virus infection.

    Science.gov (United States)

    Krain, Lisa J; Nelson, Kenrad E; Labrique, Alain B

    2014-01-01

    Hepatitis E virus (HEV), identified over 30 years ago, remains a serious threat to life, health, and productivity in developing countries where access to clean water is limited. Recognition that HEV also circulates as a zoonotic and food-borne pathogen in developed countries is more recent. Even without treatment, most cases of HEV-related acute viral hepatitis (with or without jaundice) resolve within 1 to 2 months. However, HEV sometimes leads to acute liver failure, chronic infection, or extrahepatic symptoms. The mechanisms of pathogenesis appear to be substantially immune mediated. This review covers the epidemiology of HEV infection worldwide, the humoral and cellular immune responses to HEV, and the persistence and protection of antibodies produced in response to both natural infection and vaccines. We focus on the contributions of altered immune states (associated with pregnancy, human immunodeficiency virus [HIV], and immunosuppressive agents used in cancer and transplant medicine) to the elevated risks of chronic infection (in immunosuppressed/immunocompromised patients) and acute liver failure and mortality (among pregnant women). We conclude by discussing outstanding questions about the immune response to HEV and interactions with hormones and comorbid conditions. These questions take on heightened importance now that a vaccine is available.

  5. [BK virus infection in a pediatric renal transplant recipient].

    Science.gov (United States)

    Bonaventura, R; Vázquez, A; Exeni, A; Rivero, K; Freire, M C

    2005-01-01

    BK Human Polyomavirus causes an asymptomatic primary infection in children, then establishing latency mainly in the urinary tratt. Viral reactivation can lead to renal pathology in individuals with impaired cellular immune response. This is particularly important in pediatric transplant recipients, who can suffer a primary infection when immunosupressed. We followed up the case of a 5 years old patient who received a renal transplant in October 2003, and presented damaged graft 45 days after the intervention. The patient suffered 3 episodes of renal function failure between October 2003 and June 2004. Blood, urine, renal biopsy and lymphocele liquid samples were analyzed. A differential diagnosis between acute rejection and infectious causes was established by testing for BK, CMV and ADV viruses, and the cytological study of renal tissue. Laboratory findings together with clinical signs suggest the patient was infected by BK virus. As a final consideration, the great importance of differentiating between acute rejection and BK infection is emphasized, since immunosuppressant management is opposite in each case.

  6. Diagnostic strategy for occult hepatitis B virus infection

    Institute of Scientific and Technical Information of China (English)

    Sara Ocana; Maria Luisa Casas; Ingrid Buhigas; Jose Luis Lledo

    2011-01-01

    In 2008, the European Association for the study of the liver (EASL) defined occult hepatitis B virus infection (OBI) as the "presence of hepatitis B virus (HBV) DNA in the liver (with detectable or undetectable HBV DNA in the serum) of individuals testing hepatitis B surface antigen (HBsAg) negative by currently available assays". Several aspects of occult HBV infection are still poorly understood, including the definition itself and a standardized approach for laboratory-based detection, which is the purpose of this review. The clinical significance of OBI has not yet been established; however, in terms of public health, the clinical importance arises from the risk of HBV transmission. Consequently, it is important to detect high-risk groups for occult HBV infection to prevent transmission. The main issue is, perhaps, to identify the target population for screening OBI. Viremia is very low or undetectable in occult HBV infection, even when the most sensitive methods are used, and the detection of the viral DNA reservoir in hepatocytes would provide the best evaluation of occult HBV prevalence in a defined set of patients. However, this diagnostic approach is obviously unsuitable: blood detection of occult hepatitis B requires assays of the highest sensitivity and specificity with a lower limit of detection < 10 IU/mL for HBV DNA and < 0.1 ng/mL for HBsAg.

  7. Porcine epidemic diarrhea virus infection: Etiology, epidemiology, pathogenesis and immunoprophylaxis.

    Science.gov (United States)

    Jung, Kwonil; Saif, Linda J

    2015-05-01

    Porcine epidemic diarrhea virus (PEDV), a member of the genera Alphacoronavirus in the family Coronaviridae, causes acute diarrhea/vomiting, dehydration and high mortality in seronegative neonatal piglets. For the last three decades, PEDV infection has resulted in significant economic losses in the European and Asian pig industries, but in 2013-2014 the disease was also reported in the US, Canada and Mexico. The PED epidemic in the US, from April 2013 to the present, has led to the loss of more than 10% of the US pig population. The disappearance and re-emergence of epidemic PED indicates that the virus is able to escape from current vaccination protocols, biosecurity and control systems. Endemic PED is a significant problem, which is exacerbated by the emergence (or potential importation) of multiple PEDV variants. Epidemic PEDV strains spread rapidly and cause a high number of pig deaths. These strains are highly enteropathogenic and acutely infect villous epithelial cells of the entire small and large intestines although the jejunum and ileum are the primary sites. PEDV infections cause acute, severe atrophic enteritis accompanied by viremia that leads to profound diarrhea and vomiting, followed by extensive dehydration, which is the major cause of death in nursing piglets. A comprehensive understanding of the pathogenic characteristics of epidemic or endemic PEDV strains is needed to prevent and control the disease in affected regions and to develop an effective vaccine. This review focuses on the etiology, epidemiology, disease mechanisms and pathogenesis as well as immunoprophylaxis against PEDV infection.

  8. Effects of lyophilization on the infectivity of enveloped and non-enveloped viruses in bone tissue.

    Science.gov (United States)

    Uhlenhaut, Christine; Dörner, Thomas; Pauli, Georg; Pruss, Axel

    2005-11-01

    Recently reported qualitative experiments proved that retroviral infectivity is not destroyed by lyophilization performed on systemically infected bone and tendon. The now accomplished quantitative determination of residual infectivity for enveloped and non-enveloped viruses allows a validation of the production process regarding viral safety in freeze-dried bone transplants. The lyophilization effect on the infectivity of two non-enveloped viruses (Maus Elberfeld virus, MEV; Porcine parvovirus, PPV) and one enveloped virus (Vesicular Stomatitis virus, VSV) was examined for virus-spiked bone material in comparison to lyophilized viruses, original virus stock, and air-dried viruses. All experiments were carried out with both cell-free and cell-associated virus. Significant differences were observed regarding the reduction of virus titers (TCID50). Infectivity of VSV was reduced by about 3-4 log10 using lyophilization in presence of bone matrix and of MEV by 6-7 log10, while no substantial reduction in virus titers was observed for PPV. Lyophilization of cell-free or cell-associated virus is not sufficient to inactivate viruses completely. However, lyophilization could have an additive effect in line with other production steps used in the manufacturing process.

  9. Chronic Hepatitis B and C Virus Infection and Risk for Non-Hodgkin Lymphoma in HIV-Infected Patients

    DEFF Research Database (Denmark)

    Wang, Qing; De Luca, Andrea; Smith, Colette

    2017-01-01

    Background: Non-Hodgkin lymphoma (NHL) is the most common AIDS-defining condition in the era of antiretroviral therapy (ART). Whether chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infection promote NHL in HIV-infected patients is unclear. Objective: To investigate whether chronic HB...

  10. Impact of lipids and lipoproteins on hepatitis C virus infection and virus neutralization.

    Science.gov (United States)

    Vercauteren, Koen; Mesalam, Ahmed Atef; Leroux-Roels, Geert; Meuleman, Philip

    2014-11-21

    Hepatitis C virus (HCV) infections represent a major global health problem. End-stage liver disease caused by chronic HCV infection is a major indication for liver transplantation. However, after transplantation the engrafted liver inevitably becomes infected by the circulating virus. Direct acting antivirals are not yet approved for use in liver transplant patients, and limited efficacy and severe side effects hamper the use of pegylated interferon combined with ribavirin in a post-transplant setting. Therefore, alternative therapeutic options need to be explored. Viral entry represents an attractive target for such therapeutic intervention. Understanding the mechanisms of viral entry is essential to define the viral and cellular factors involved. The HCV life cycle is dependent of and associated with lipoprotein physiology and the presence of lipoproteins has been correlated with altered antiviral efficacy of entry inhibitors. In this review, we summarise the current knowledge on how lipoprotein physiology influences the HCV life cycle. We focus especially on the influence of lipoproteins on antibodies that target HCV envelope proteins or antibodies that target the cellular receptors of the virus. This information can be particularly relevant for the prevention of HCV re-infection after liver transplantation.

  11. 8 People Infected in Rare U.S. Outbreak of Rat Virus

    Science.gov (United States)

    ... Prevention. Seoul virus is a member of the Hantavirus family of rodent-borne viruses and is carried ... MedlinePlus Health Topics Animal Diseases and Your Health Hantavirus Infections About MedlinePlus Site Map FAQs Customer Support ...

  12. Chronic active Epstein-Barr virus infection in an adult with no detectable immune deficiency.

    NARCIS (Netherlands)

    Boer, M. de; Mol, M.J.T.M.; Bogman, M.J.J.T.; Galama, J.M.D.; Raymakers, R.A.P.

    2003-01-01

    INTRODUCTION: Epstein-Barr virus (EBV) establishes lifelong latent infection. In some patients the host-virus balance is disturbed, resulting in a chronic active EBV infection. The following case illustrates the difficulty in diagnosing and treating chronic EBV infection. CASE: A 30-year-old woman w

  13. Infection with A2 Hong Kong influenza virus in domestic cats.

    Science.gov (United States)

    Paniker, C K; Nair, C M

    1970-01-01

    The antigenic relationship of A2 Hong Kong influenza virus with equine influenza virus, and its ability to infect horses and baboons, have led to studies on the susceptibility of domestic animals to the virus.In this study it was found that cats could be infected with A2 Hong Kong influenza virus by intranasal inoculation or by contact with an infected cat or with a human influenza patient. There was no clinical illness, but infected animals shed the virus from the throat for 1 week and developed haemagglutination-inhibiting antibodies. A survey of normal cat sera showed that 6 out of 28 sera inhibited haemagglutination by A2 Hong Kong influenza virus.The results suggest that domestic cats may act as vectors in the transmission of influenza virus. Experimental infection in cats may be used as a laboratory model for influenza.

  14. Infection with A2 Hong Kong influenza virus in domestic cats*

    Science.gov (United States)

    Paniker, C. K. J.; Nair, C. M. G.

    1970-01-01

    The antigenic relationship of A2 Hong Kong influenza virus with equine influenza virus, and its ability to infect horses and baboons, have led to studies on the susceptibility of domestic animals to the virus. In this study it was found that cats could be infected with A2 Hong Kong influenza virus by intranasal inoculation or by contact with an infected cat or with a human influenza patient. There was no clinical illness, but infected animals shed the virus from the throat for 1 week and developed haemagglutination-inhibiting antibodies. A survey of normal cat sera showed that 6 out of 28 sera inhibited haemagglutination by A2 Hong Kong influenza virus. The results suggest that domestic cats may act as vectors in the transmission of influenza virus. Experimental infection in cats may be used as a laboratory model for influenza. PMID:5314017

  15. Orsay, Santeuil and Le Blanc viruses primarily infect intestinal cells in Caenorhabditis nematodes.

    Science.gov (United States)

    Franz, Carl J; Renshaw, Hilary; Frezal, Lise; Jiang, Yanfang; Félix, Marie-Anne; Wang, David

    2014-01-05

    The discoveries of Orsay, Santeuil and Le Blanc viruses, three viruses infecting either Caenorhabditis elegans or its relative Caenorhabditis briggsae, enable the study of virus-host interactions using natural pathogens of these two well-established model organisms. We characterized the tissue tropism of infection in Caenorhabditis nematodes by these viruses. Using immunofluorescence assays targeting proteins from each of the viruses, and in situ hybridization, we demonstrate viral proteins and RNAs localize to intestinal cells in larval stage Caenorhabditis nematodes. Viral proteins were detected in one to six of the 20 intestinal cells present in Caenorhabditis nematodes. In Orsay virus-infected C. elegans, viral proteins were detected as early as 6h post-infection. The RNA-dependent RNA polymerase and capsid proteins of Orsay virus exhibited different subcellular localization patterns. Collectively, these observations provide the first experimental insights into viral protein expression in any nematode host, and broaden our understanding of viral infection in Caenorhabditis nematodes.

  16. Molecular evidence of simian virus 40 infections in children

    Science.gov (United States)

    Butel, J. S.; Arrington, A. S.; Wong, C.; Lednicky, J. A.; Finegold, M. J.

    1999-01-01

    Recent studies have detected simian virus 40 (SV40) DNA in certain human tumors and normal tissues. The significance of human infections by SV40, which was first discovered as a contaminant of poliovirus vaccines used between 1955 and 1963, remains unknown. The occurrence of SV40 infections in unselected hospitalized children was evaluated. Polymerase chain reaction and DNA sequence analyses were done on archival tissue specimens from patients positive for SV40 neutralizing antibody. SV40 DNA was identified in samples from 4 of 20 children (1 Wilms' tumor, 3 transplanted kidney samples). Sequence variation among SV40 regulatory regions ruled out laboratory contamination of specimens. This study shows the presence of SV40 infections in pediatric patients born after 1982.

  17. An overview of occult hepatitis B virus infection

    Institute of Scientific and Technical Information of China (English)

    Zeinab Nabil Ahmed Said

    2011-01-01

    Occult hepatitis B virus (HBV) infection (OBI), alternatively defined as occult hepatitis B (OHB), is a challenging clinical entity. It is recognized by two main characteristics: absence of HBsAg, and low viral replication. The previous two decades have witnessed a remarkable progress in our nderstanding of OBI and its clinical implications. Appropriate diagnostic techniques must be adopted. Sensitive HBV DNA amplification assay is the gold standard assay for detection of OBI. Viral as well as host factors are implicated in the pathogenesis of OBI. However, published data reporting the infectivity of OBI by transfusion are limited. Several aspects including OBI transmission, infectivity and its relation to the development of chronic liver diseases and hepatocellular carcinoma have to be resolved. The aim of the present review is to highlight recent data on OBI with a focus on its virological diagnosis and clinical outcome.

  18. Clinical, Pathological and Immunological Aspects of Transplacental PRRS Virus Infection

    DEFF Research Database (Denmark)

    Nielsen, Jens

    2011-01-01

    The present paper describes Danish research activities on porcine reproductive and respiratory syndrome (PRRS) with emphasis on experimental infections in pregnant swine. The first case of PRRS was diagnosed in Denmark in 1992 and subsequently the disease spread to most other parts of the country....... The first animal experiments elucidated the pathogenicity of Danish PRRS virus (PRRSV) isolates in pregnant sows together with the effects of infection at various stages of gestation. In 1996, the introduction of a vaccination program using an attenuated live PRRS vaccine led to an epidemic of American type...... PRRSV in the previously unaffected Danish pig population. Acute PRRS like disease was observed in non-vaccinated as well as in vaccinated herds, and it was demonstrated that the vaccine strain had reverted to virulence. By experimental infection of late term pregnant sows, we demonstrated that a field...

  19. Hepatitis C virus infection in hemodialysis patients in Maracaibo, Venezuela

    Directory of Open Access Journals (Sweden)

    Francisca Monsalve-Castillo

    2012-02-01

    Full Text Available Over a two year period, the incidence of hepatitis C virus (HCV infection was evaluated in 29 hemodialysis patients, aged between 15 and 75 years (mean ± SD: 45 ± 39.5 years, from the University Hospital Hemodyalisis Unit, Maracaibo, Zulia State, Venezuela. Anti-HCV antibodies were determined using a fourth generation ELISA (Innotest HCV Ab IV kit and positive blood samples were tested using a recombinant assay kit (Inno-LIA HCV Ab III, both kits from Innogenetics N.V., Belgium. The findings indicate a lack of HCV seroconversion in the hemodialysis patients over the study period, confirmed by the recombinant assay. Risk factors for HCV infection were 0.3270 (95% confidence interval: 0.01323-8.080 in patients undergoing hemodialysis. The findings suggest a lack of significant sources for HCV infection due to the preventive measures to avoid its transmission in the hemodialysis unit.

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

    Directory of Open Access Journals (Sweden)

    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.

  1. Experimental Infections of Wild Birds with West Nile Virus

    Directory of Open Access Journals (Sweden)

    Elisa Pérez-Ramírez

    2014-02-01

    Full Text Available Avian models of West Nile virus (WNV disease have become pivotal in the study of infection pathogenesis and transmission, despite the intrinsic constraints that represents this type of experimental research that needs to be conducted in biosecurity level 3 (BSL3 facilities. This review summarizes the main achievements of WNV experimental research carried out in wild birds, highlighting advantages and limitations of this model. Viral and host factors that determine the infection outcome are analyzed in detail, as well as recent discoveries about avian immunity, viral transmission, and persistence achieved through experimental research. Studies of laboratory infections in the natural host will help to understand variations in susceptibility and reservoir competence among bird species, as well as in the epidemiological patterns found in different affected areas.

  2. Novel approaches towards conquering hepatitis B virus infection

    Institute of Scientific and Technical Information of China (English)

    Guo-Yi Wu; Hong-Song Chen

    2007-01-01

    Currently approved treatments for hepatitis B virus (HBV) infection include the immunomodulatory agent, IFN-a, and nucleos(t)ide analogues. Their efficacy is limited by their side effects, as well as the induction of viral mutations that render them less potent. It is thus necessary to develop drugs that target additional viral antigens. Chemicals and biomaterials by unique methods of preventing HBV replication are currently being developed, including novel nucleosides and newly synthesized compounds such as capsid assembling and mRNA transcription inhibitors. Molecular therapies that target different stages of the HBV life cycle will aid current methods to manage chronic hepatitis B (CHB) infection. The use of immunomodulators and gene therapy are also under consideration. This report summarizes the most recent treatment possibilities for CHB infection. Emerging therapies and their potential mechanisms, efficacy, and pitfalls are discussed.

  3. Emerging bone problems in patients infected with human immunodeficiency virus.

    Science.gov (United States)

    Mondy, Kristin; Tebas, Pablo

    2003-04-01

    Recently, a high incidence of osteopenia and osteoporosis has been observed in individuals infected with human immunodeficiency virus (HIV). This problem appears to be more frequent in patients receiving potent antiretroviral therapy. Other bone-related complications in HIV-infected individuals, including avascular necrosis of the hip and compression fracture of the lumbar spine, have also been reported. People living with HIV have significant alterations in bone metabolism, regardless of whether they are receiving potent antiretroviral therapy. The underlying mechanisms to account for these observations remain unknown, although studies are underway to examine the relationship between the bone abnormalities and other complications associated with HIV and antiretroviral therapy. HIV-infected patients with osteopenia or osteoporosis should be treated similarly to HIV-seronegative patients with appropriate use of nutritional supplements (calcium and vitamin D) and exercise. Hormone replacement and antiresorptive therapies might be also indicated.

  4. [Pulmonary complications in children with human immunodeficiency virus infection].

    Science.gov (United States)

    Brockmann V, Pablo; Viviani S, Támara; Peña D, Anamaría

    2007-08-01

    Pulmonary complications in children infected by human immunodeficiency virus (HIV) are common and may be the first manifestation of acquired immunodeficiency syndrome (AIDS). The aim of our study was to review pulmonary diseases and complications in pediatric patients with HIV infection in a large tertiary hospital in Santiago, Chile. We performed a retrospective, descriptive analysis of 17 patients with HIV infection controlled at the Hospital Dr. Sótero del Rio. Respiratory complications/diseases were: overall pneumonia (n: 14), recurrent pneumonia (n: 10), citomegalovirus associated pneumonia (n: 4), Pneumocystis jiroveci associated pneumonia (n: 1) pulmonary tuberculosis (n: 1), lymphoid interstitial pneumonia (n: 3) and chronic pulmonary disease (n: 7). Microorganisms isolated were mostly atypical and frequently associated with severe and chronic pulmonary damage. A high degree of suspicion is required to detect atypical microorganisms promptly, in order to rapidly implement pathogen targeted therapy that could potentially decrease the possibility of sequelae.

  5. Emphysematous Cholecystitis: A Rare Complication of Hepatitis A Virus Infection

    Directory of Open Access Journals (Sweden)

    Ahmet KARAKAS

    2015-03-01

    Full Text Available Hepatitis A virus (HAV causes an acute hepatitis associated with significant elevatation in liver enzymes. The liver is main target of HAV and extrahepatic manifestations are scarce. The diagnosis of acute HAV infection is made by the detection of anti-HAV IgM antibody in patients with the typical clinical presentation.. Here in, we present a 22-year old male presented with malaise, fever, nause, and intensive stomach ache. In physical examination, the patient had fever, jaundice, and hepatomegaly. Laboratory tests resulted in elevated liver enzymes. Abdominal ultrasonography demonstrated thickening of the gallbladder wall, and intramural air. As the patient's symptoms failed to regress in follow up laparoscopic cholecystectomy was performed. To sum up, HAV infection can be seen in all age groups, in developing countries, such as our country. It must be kept in mind that, although very rarely, HAV infections may exhibit extrahepatic complications. [Dis Mol Med 2015; 3(1.000: 5-7

  6. Transcriptome analysis of Aedes aegypti in response to mono-infections and co-infections of dengue virus-2 and chikungunya virus.

    Science.gov (United States)

    Shrinet, Jatin; Srivastava, Pratibha; Sunil, Sujatha

    2017-02-01

    Chikungunya virus (CHIKV) and Dengue virus (DENV) spread via the bite of infected Aedes mosquitoes. Both these viruses exist as co-infections in the host as well as the vector and are known to exploit their cellular machinery for their replication. While there are studies reporting the changes in Aedes transcriptome when infected with DENV and CHIKV individually, the effect both these viruses have on the mosquitoes when present as co-infections is not clearly understood. In the present study, we infected Aedes aegypti mosquitoes with DENV and CHIKV individually and as co-infection through nanoinjections. We performed high throughput RNA sequencing of the infected Aedes aegypti to understand the changes in the Aedes transcriptome during the early stages of infection, i.e., 24 h post infection and compared the transcriptome profiles during DENV and CHIKV mono-infections with that of co-infections. We identified 190 significantly regulated genes identified in CHIKV infected library, 37 genes from DENV library and 100 genes from co-infected library and they were classified into different pathways. Our study reveal that distinct pathways and transcripts are being regulated during the three types of infection states in Aedes aegypti mosquitoes.

  7. Differential proteome analysis of chikungunya virus infection on host cells.

    Directory of Open Access Journals (Sweden)

    Christina Li-Ping Thio

    Full Text Available BACKGROUND: Chikungunya virus (CHIKV is an emerging mosquito-borne alphavirus that has caused multiple unprecedented and re-emerging outbreaks in both tropical and temperate countries. Despite ongoing research efforts, the underlying factors involved in facilitating CHIKV replication during early infection remains ill-characterized. The present study serves to identify host proteins modulated in response to early CHIKV infection using a proteomics approach. METHODOLOGY AND PRINCIPAL FINDINGS: The whole cell proteome profiles of CHIKV-infected and mock control WRL-68 cells were compared and analyzed using two-dimensional gel electrophoresis (2-DGE. Fifty-three spots were found to be differentially modulated and 50 were successfully identified by MALDI-TOF/TOF. Eight were significantly up-regulated and 42 were down-regulated. The mRNA expressions of 15 genes were also found to correlate with the corresponding protein expression. STRING network analysis identified several biological processes to be affected, including mRNA processing, translation, energy production and cellular metabolism, ubiquitin-proteasome pathway (UPP and cell cycle regulation. CONCLUSION/SIGNIFICANCE: This study constitutes a first attempt to investigate alteration of the host cellular proteome during early CHIKV infection. Our proteomics data showed that during early infection, CHIKV affected the expression of proteins that are involved in mRNA processing, host metabolic machinery, UPP, and cyclin-dependent kinase 1 (CDK1 regulation (in favour of virus survival, replication and transmission. While results from this study complement the proteomics results obtained from previous late host response studies, functional characterization of these proteins is warranted to reinforce our understanding of their roles during early CHIKV infection in humans.

  8. Mouse models of dengue virus infection for vaccine testing.

    Science.gov (United States)

    Sarathy, Vanessa V; Milligan, Gregg N; Bourne, Nigel; Barrett, Alan D T

    2015-12-10

    Dengue is a mosquito-borne disease caused by four serologically and genetically related viruses termed DENV-1 to DENV-4. With an annual global burden of approximately 390 million infections occurring in the tropics and subtropics worldwide, an effective vaccine to combat dengue is urgently needed. Historically, a major impediment to dengue research has been development of a suitable small animal infection model that mimics the features of human illness in the absence of neurologic disease that was the hallmark of earlier mouse models. Recent advances in immunocompromised murine infection models have resulted in development of lethal DENV-2, DENV-3 and DENV-4 models in AG129 mice that are deficient in both the interferon-α/β receptor (IFN-α/β R) and the interferon-γ receptor (IFN-γR). These models mimic many hallmark features of dengue disease in humans, such as viremia, thrombocytopenia, vascular leakage, and cytokine storm. Importantly AG129 mice develop lethal, acute, disseminated infection with systemic viral loads, which is characteristic of typical dengue illness. Infected AG129 mice generate an antibody response to DENV, and antibody-dependent enhancement (ADE) models have been established by both passive and maternal transfer of DENV-immune sera. Several steps have been taken to refine DENV mouse models. Viruses generated by peripheral in vivo passages incur substitutions that provide a virulent phenotype using smaller inocula. Because IFN signaling has a major role in immunity to DENV, mice that generate a cellular immune response are desired, but striking the balance between susceptibility to DENV and intact immunity is complicated. Great strides have been made using single-deficient IFN-α/βR mice for DENV-2 infection, and conditional knockdowns may offer additional approaches to provide a panoramic view that includes viral virulence and host immunity. Ultimately, the DENV AG129 mouse models result in reproducible lethality and offer multiple

  9. Occult persistence and lymphotropism of hepatitis C virus infection

    Institute of Scientific and Technical Information of China (English)

    Tram NQ Pham; Tomasz I Michalak

    2008-01-01

    Recent discovery of occult hepatitis C virus (HCV)infection persisting after spontaneous or antiviral therapy-induced resolution of hepatitis C was made possible by the introduction of nucleic acid amplification assays capable of detecting HCV RNA at sensitivities superseding those offered by clinical tests. Although individuals with this seemingly silent HCV infection are usually anti-HCV antibody reactive and have normal liver function tests, occult HCV infection has also been reported in anti-HCV-negative individuals with persistently elevated liver enzymes of unknown etiology. Studies have shown that HCV RNA can persist for years in serum, iymphomononuciear cells and liver in the absence of clinical symptoms, although histological evidence of a mild inflammatory liver injury can be occasionally encountered. Furthermore, while HCV RNA can be detected in circulating lymphoid cells in approximately 30% of cases, a short-term culture under stimulatory conditions augments HCV replication in these cells allowing detection of virus in otherwise HCV-negative cases. HCV infects different immune cell subsets, including CD4+ and CD8+ T lymphocytes, B cells and monocytes. Studies employing cional sequencing and single-stranded conformational polymorphism analyses have revealed unique HCV variants residing in immune cells, further strengthening the notion of HCV lymphotropism. Overall, the data accumulated suggest that occult HCV infection is a common consequence of resolution of symptomatic hepatitis C and that examination of the cells of the immune system is an effective approach to diagnosis of HCV infection and its long-term persistence. Further work is required to fully realize pathogenic and epidemiological consequences of occult HCV persistence.

  10. Functional CD8+ T Cell Responses in Lethal Ebola Virus Infection

    Science.gov (United States)

    2008-03-15

    2003. Cutting edge: impairment of dendritic cells and adaptive immunity by Ebola and Lassa viruses . J. Immunol. 170: 2797–2801. 20. Bosio, C. M., B...Functional CD8 T Cell Responses in Lethal Ebola Virus Infection1 Steven B. Bradfute, Kelly L. Warfield, and Sina Bavari2 Ebola virus (EBOV) causes...the development of an effective adap- tive immune response, leading to overwhelming infection and death. Ebola virus (EBOV)3 is a single-stranded

  11. Occult hepatitis B virus infection and S gene escape mutants in HIV-infected patients after hepatitis B virus vaccination.

    Science.gov (United States)

    Aghakhani, Arezoo; Mohraz, Minoo; Aghasadeghi, Mohammad Reza; Banifazl, Mohammad; Vahabpour, Rouhollah; Karami, Afsaneh; Foroughi, Maryam; Ramezani, Amitis

    2016-10-01

    Hepatitis B virus (HBV) vaccination is recommended for HIV patients. Despite the relative success of HBV vaccination, breakthrough infections can occur infrequently in patients, and it can be due to occult HBV infection, vaccine unresponsiveness and/or emergence of escape mutants. This study assessed the presence of occult HBV infection and S gene escape mutants in HIV-positive patients after HBV vaccination. Ninety-two HIV-positive patients were enrolled in this study, including 52 responders to HBV vaccine and 40 non-responders. All of the cases received HBV vaccine according to routine HBV vaccination protocols. The presence of HBV-DNA was determined by real-time polymerase chain reaction (PCR). In HBV-DNA positive samples, the most conserved regions of S gene sequences were amplified by nested PCR and PCR products were sequenced. Occult HBV infection was detected in two cases. Glycine to arginine mutation at residue 145 (G145R) within the 'a' region of the S gene was detected in one of the occult HBV infection cases who was in the non-responder group. This study showed that the prevalence of occult HBV infection and vaccine escape mutants was low in our HBV-vaccinated HIV-positive patients in both responder and non-responder groups, so there was no alarming evidence indicating breakthrough HBV infection in our vaccinated HIV-positive cases.

  12. Taishan Pinus massoniana pollen polysaccharide inhibits subgroup J avian leucosis virus infection by directly blocking virus infection and improving immunity.

    Science.gov (United States)

    Yu, Cuilian; Wei, Kai; Liu, Liping; Yang, Shifa; Hu, Liping; Zhao, Peng; Meng, Xiuyan; Shao, Mingxu; Wang, Chuanwen; Zhu, Lijun; Zhang, Hao; Li, Yang; Zhu, Ruiliang

    2017-03-13

    Subgroup J avian leucosis virus (ALV-J) generally causes neoplastic diseases, immunosuppression and subsequently increases susceptibility to secondary infection in birds. The spread of ALV-J mainly depends on congenital infection and horizontal contact. Although ALV-J infection causes enormous losses yearly in the poultry industry worldwide, effective measures to control ALV-J remain lacking. In this study, we demonstrated that Taishan Pinus massoniana pollen polysaccharide (TPPPS), a natural polysaccharide extracted from Taishan Pinus massoniana pollen, can significantly inhibit ALV-J replication in vitro by blocking viral adsorption to host cells. Electron microscopy and blocking ELISA tests revealed that TPPPS possibly blocks viral adsorption to host cells by interacting with the glycoprotein 85 protein of ALV-J. Furthermore, we artificially established a congenitally ALV-J-infected chicken model to examine the anti-viral effects of TPPPS in vivo. TPPPS significantly inhibited viral shedding and viral loads in immune organs and largely eliminated the immunosuppression caused by congenital ALV-J infection. Additionally, pre-administration of TPPPS obviously reduced the size and delayed the occurrence of tumors induced by acute oncogenic ALV-J infection. This study revealed the prominent effects and feasible mechanisms of TPPPS in inhibiting ALV-J infection, thereby providing a novel prospect to control ALV-J spread.

  13. Occult hepatitis C virus infection among hemodialysis patients.

    Science.gov (United States)

    Barril, Guillermina; Castillo, Inmaculada; Arenas, María Dolores; Espinosa, Mario; Garcia-Valdecasas, Juan; Garcia-Fernández, Nuria; González-Parra, Emilio; Alcazar, José María; Sánchez, Carmen; Diez-Baylón, José Carlos; Martinez, Pilar; Bartolomé, Javier; Carreño, Vicente

    2008-12-01

    Occult hepatitis C virus (HCV) infection (i.e., detectable HCV-RNA in the liver or peripheral blood mononuclear cells) in the absence of both serum HCV-RNA and anti-HCV antibodies has not been investigated in hemodialysis patients. In this study, real-time PCR and in situ hybridization was used to test for the presence of genomic and antigenomic HCV-RNA in peripheral blood mononuclear cells of 109 hemodialysis patients with abnormal levels of liver enzymes. Occult HCV infection, determined by the presence of genomic HCV-RNA, was found in 45% of the patients; 53% of these patients had ongoing HCV replication, indicated by the presence of antigenomic HCV-RNA. Patients with occult HCV infection had spent a significantly longer time on hemodialysis and had significantly higher mean alanine aminotransferase levels during the 6 mo before study entry. Logistic regression analysis revealed that mortality was associated with age >60 yr (odds ratio 3.30; 95% confidence interval 1.05 to 10.33) and the presence of occult HCV infection (odds ratio 3.84; 95% confidence interval 1.29 to 11.43). In conclusion, the prevalence of occult HCV infection is high among hemodialysis patients with persistently abnormal values of liver enzymes of unknown cause. The clinical significance of occult HCV infection in these patients requires further study.

  14. Zika virus infection-the next wave after dengue?

    Science.gov (United States)

    Wong, Samson Sai-Yin; Poon, Rosana Wing-Shan; Wong, Sally Cheuk-Ying

    2016-04-01

    Zika virus was initially discovered in east Africa about 70 years ago and remained a neglected arboviral disease in Africa and Southeast Asia. The virus first came into the limelight in 2007 when it caused an outbreak in Micronesia. In the ensuing decade, it spread widely in other Pacific islands, after which its incursion into Brazil in 2015 led to a widespread epidemic in Latin America. In most infected patients the disease is relatively benign. Serious complications include Guillain-Barré syndrome and congenital infection which may lead to microcephaly and maculopathy. Aedes mosquitoes are the main vectors, in particular, Ae. aegypti. Ae. albopictus is another potential vector. Since the competent mosquito vectors are highly prevalent in most tropical and subtropical countries, introduction of the virus to these areas could readily result in endemic transmission of the disease. The priorities of control include reinforcing education of travellers to and residents of endemic areas, preventing further local transmission by vectors, and an integrated vector management programme. The container habitats of Ae. aegypti and Ae. albopictus means engagement of the community and citizens is of utmost importance to the success of vector control.

  15. Infection with Hepatitis C Virus among HIV-Infected Pregnant Women in Thailand

    Directory of Open Access Journals (Sweden)

    Denise J. Jamieson

    2008-01-01

    Full Text Available Objective. The purpose of this study was to describe the epidemiology of coinfection with hepatitis C virus (HCV and HIV among a cohort of pregnant Thai women. Methods. Samples from 1771 pregnant women enrolled in three vertical transmission of HIV studies in Bangkok, Thailand, were tested for HCV. Results. Among HIV-infected pregnant women, HCV seroprevelance was 3.8% and the active HCV infection rate was 3.0%. Among HIV-uninfected pregnant women, 0.3% were HCV-infected. Intravenous drug use by the woman was the factor most strongly associated with HCV seropositivity. Among 48 infants tested for HCV who were born to HIV/HCV coinfected women, two infants were HCV infected for an HCV transmission rate of 4.2% (95% 0.51–14.25%. Conclusions. HCV seroprevalence and perinatal transmission rates were low among this Thai cohort of HIV-infected pregnant women.

  16. Involvement of the plant nucleolus in virus and viroid infections: parallels with animal pathosystems.

    Science.gov (United States)

    Taliansky, M E; Brown, J W S; Rajamäki, M L; Valkonen, J P T; Kalinina, N O

    2010-01-01

    The nucleolus is a dynamic subnuclear body with roles in ribosome subunit biogenesis, mediation of cell-stress responses, and regulation of cell growth. An increasing number of reports reveal that similar to the proteins of animal viruses, many plant virus proteins localize in the nucleolus to divert host nucleolar proteins from their natural functions in order to exert novel role(s) in the virus infection cycle. This chapter will highlight studies showing how plant viruses recruit nucleolar functions to facilitate virus translation and replication, virus movement and assembly of virus-specific ribonucleoprotein (RNP) particles, and to counteract plant host defense responses. Plant viruses also provide a valuable tool to gain new insights into novel nucleolar functions and processes. Investigating the interactions between plant viruses and the nucleolus will facilitate the design of novel strategies to control plant virus infections.

  17. Modification of Non-Vector Aphid Feeding Behavior on Virus-Infected Host Plant

    OpenAIRE

    Hu, Zuqing; Zhao, Huiyan; Thieme, Thomas

    2013-01-01

    Virus-infected host plants can have positive, neutral or negative effects on vector aphids. Even though the proportion of non-vector aphids associated with a plant far exceeds that of vector species, little is known about the effect of virus-infected plants on non-vector aphids. In the present study, the English grain aphid Sitobion avenae (Fabricius) (Hemiptera: Aphididae), a non-vector of Wheat dwarf virus (WDV) and Cereal yellow dwarf virus-RPV (CYDV-RPV), was monitored on, virus-infected,...

  18. TT virus infection and pancreatic cancer: Relationship or accidental coexistence

    Institute of Scientific and Technical Information of China (English)

    Krzysztof Tomasiewicz; Roma Modrzewska; Anna Lyczak; Grazyna Krawczuk

    2005-01-01

    TT virus (TTV) was first isolated in 1997 from the patient with acute post-transfusion hepatitis. This fact led to the conclusion that the virus was hepatotropic and could be one of the causative agents of acute hepatitis. Afterwards, however, the virus was found in other human tissues and serological studies revealed that it was widespread. Multiple tropisms of TTV and the fact of its high incidence in general population are considered to indicate no medical significance of TTV in human pathology. Here we present a report of two cases of TTV infection in patients who developed pancreas cancer. The patients were hospitalized at the Department of Infectious Diseases due to hepatitis of unknown origin. Since serological and virological markers of common primary and secondary hepatotropic viruses were negative, TTV-DNA was found in serum and was believed to be the only causative agent with probable hepatotropic action. The patients later developed pancreas cancer and they underwent operation. The relationship is difficult to confirm, however the cases we present should be treated as a preliminary report and a comment on the real role of TTV in human pathology.

  19. Noninvasive Monitoring of Hepatic Damage from Hepatitis C Virus Infection

    Directory of Open Access Journals (Sweden)

    J. Alavez-Ramírez

    2011-01-01

    Full Text Available The mathematical model for the dynamics of the hepatitis C proposed in Avendaño et al. (2002, with four populations (healthy and unhealthy hepatocytes, the viral load of the hepatitis C virus, and T killer cells, is revised. Showing that the reduced model obtained by considering only the first three of these populations, known as basic model, has two possible equilibrium states: the uninfected one where viruses are not present in the individual, and the endemic one where viruses and infected cells are present. A threshold parameter (the basic reproductive virus number is introduced, and in terms of it, the global stability of both two possible equilibrium states is established. Other central result consists in showing, by model numerical simulations, the feasibility of monitoring liver damage caused by HCV, avoiding unnecessary biopsies and the undesirable related inconveniences/imponderables to the patient; another result gives a mathematical modelling basis to recently developed techniques for the disease assessment based essentially on viral load measurements.

  20. Epizootic canine distemper virus infection among wild mammals.

    Science.gov (United States)

    Kameo, Yuki; Nagao, Yumiko; Nishio, Yohei; Shimoda, Hiroshi; Nakano, Hitoshi; Suzuki, Kazuo; Une, Yumi; Sato, Hiroshi; Shimojima, Masayuki; Maeda, Ken

    2012-01-27

    In the spring of 2007, seven raccoon dogs and a weasel were captured near the city of Tanabe in Wakayama prefecture, Japan. The causative agent of the animals' death 1-2 days after capture was identified as canine distemper virus (CDV) by virus isolation, immunostaining with an anti-CDV polyclonal antibody, and a commercially available CDV antigen-detection kit. Sequence analysis of hemagglutinin genes indicated the isolated viruses belong to genotype Asia-1 and possess the substitution from tyrosine (Y) to histidine (H) at position 549 that is associated with the spread of CDV to non-canine hosts. A serosurvey for CDV was then conducted among wild animals in the region. The animals assayed consisted of 104 raccoons, 41 wild boars, 19 raccoon dogs, five Sika deer, two badgers, one weasel, one marten, one Siberian weasel and one fox. Virus-neutralization (VN) tests showed that, except for fox and weasel, all of the species assayed had VN antibodies to CDV. Interestingly, 11 of the 41 wild boars (27%) and two of the five Sika deer assayed possessed VN antibodies to CDV. These findings indicate that CDV infection was widespread among wild mammals during this epizootic.

  1. Modeling Within-Host Dynamics of Influenza Virus Infection Including Immune Responses

    OpenAIRE

    Pawelek, Kasia A.; Huynh, Giao T; Michelle Quinlivan; Ann Cullinane; Libin Rong; Perelson, Alan S.

    2012-01-01

    Influenza virus infection remains a public health problem worldwide. The mechanisms underlying viral control during an uncomplicated influenza virus infection are not fully understood. Here, we developed a mathematical model including both innate and adaptive immune responses to study the within-host dynamics of equine influenza virus infection in horses. By comparing modeling predictions with both interferon and viral kinetic data, we examined the relative roles of target cell availability, ...

  2. Bilateral Linear Lichen Planus Pigmentosus Associated with Hepatitis C Virus Infection

    Directory of Open Access Journals (Sweden)

    Vasanop Vachiramon

    2010-09-01

    Full Text Available Lichen planus pigmentosus is a rare subtype of lichen planus. We report a first case of lichen planus pigmentosus with bilateral linear distribution associated with hepatitis C virus infection. The lesion was improved after sun avoidance and treatment of hepatitis C virus infection with a combination of interferon and ribavirin. This case stresses the importance of screening for hepatitis C virus infection as lichen planus pigmentosus can be an associated condition.

  3. Dispersed gold nanoparticles potentially ruin gold barley yellow dwarf virus and eliminate virus infectivity hazards

    Science.gov (United States)

    Alkubaisi, Noorah A.; Aref, Nagwa M. A.

    2016-10-01

    Gold nanoparticles (AuNPs) application melted barley yellow dwarf virus-PAV (BYDV-PAV) spherical nanoparticle capsids. Synergistic therapeutic effects for plant virus resistance were induced by interaction with binding units of prepared AuNPs in a water solution which was characterized and evaluated by zeta sizer, zeta potential and transmission electron microscopy (TEM). The yield of purified nanoparticles of BYDV-PAV was obtained from Hordeum vulgare (Barley) cultivars, local and Giza 121/Justo. It was 0.62 mg/ml from 27.30 g of infected leaves at an A260/A280 ratio. Virus nanoparticle has a spherical shape 30 nm in size by TEM. BYDV-PAV combined with AuNPs to challenge virus function in vivo and in vitro. Dual AuNPs existence in vivo and in vitro affected compacted configuration of viral capsid protein in the interior surface of capsomers, the outer surface, or between the interface of coat protein subunits for 24 and 48 h incubation period in vitro at room temperature. The sizes of AuNPs that had a potentially dramatic deteriorated effect are 3.151 and 31.67 nm with a different intensity of 75.3% for the former and 24.7% for the latter, which enhances optical sensing applications to eliminate virus infectivity. Damages of capsid protein due to AuNPs on the surface of virus subunits caused variable performance in four different types of TEM named puffed, deteriorated and decorated, ruined and vanished. Viral yield showed remarkably high-intensity degree of particle symmetry and uniformity in the local cultivar greater than in Giza 121/Justo cultivar. A high yield of ruined VLPs in the local cultivar than Justo cultivar was noticed. AuNPs indicated complete lysed VLPs and some deteriorated VLPs at 48 h.

  4. Dispersed gold nanoparticles potentially ruin gold barley yellow dwarf virus and eliminate virus infectivity hazards

    Science.gov (United States)

    Alkubaisi, Noorah A.; Aref, Nagwa M. A.

    2017-02-01

    Gold nanoparticles (AuNPs) application melted barley yellow dwarf virus-PAV (BYDV-PAV) spherical nanoparticle capsids. Synergistic therapeutic effects for plant virus resistance were induced by interaction with binding units of prepared AuNPs in a water solution which was characterized and evaluated by zeta sizer, zeta potential and transmission electron microscopy (TEM). The yield of purified nanoparticles of BYDV-PAV was obtained from Hordeum vulgare (Barley) cultivars, local and Giza 121/Justo. It was 0.62 mg/ml from 27.30 g of infected leaves at an A260/A280 ratio. Virus nanoparticle has a spherical shape 30 nm in size by TEM. BYDV-PAV combined with AuNPs to challenge virus function in vivo and in vitro. Dual AuNPs existence in vivo and in vitro affected compacted configuration of viral capsid protein in the interior surface of capsomers, the outer surface, or between the interface of coat protein subunits for 24 and 48 h incubation period in vitro at room temperature. The sizes of AuNPs that had a potentially dramatic deteriorated effect are 3.151 and 31.67 nm with a different intensity of 75.3% for the former and 24.7% for the latter, which enhances optical sensing applications to eliminate virus infectivity. Damages of capsid protein due to AuNPs on the surface of virus subunits caused variable performance in four different types of TEM named puffed, deteriorated and decorated, ruined and vanished. Viral yield showed remarkably high-intensity degree of particle symmetry and uniformity in the local cultivar greater than in Giza 121/Justo cultivar. A high yield of ruined VLPs in the local cultivar than Justo cultivar was noticed. AuNPs indicated complete lysed VLPs and some deteriorated VLPs at 48 h.

  5. Expression of the Lassa virus nucleocapsid protein in insect cells infected with a recombinant baculovirus: application to diagnostic assays for Lassa virus infection.

    Science.gov (United States)

    Barber, G N; Clegg, J C; Lloyd, G

    1990-01-01

    The coding region of the gene for the nucleocapsid protein of Lassa virus has been inserted into the genome of Autographa californica nuclear polyhedrosis virus (AcNPV) using the transfer vector pAcYM1, so that expression of the foreign DNA is under the control of the promoter of the AcNPV polyhedrin gene. Infection of cultured Spodoptera frugiperda cells with recombinant virus resulted in the synthesis of high levels of a protein that was indistinguishable from the authentic Lassa virus protein by SDS gel electrophoresis and immunoblotting with a variety of specific immune sera and monoclonal antibodies (MAbs). The kinetics of appearance of the protein were comparable to those of polyhedrin production in wild-type AcNPV-infected cells. The recombinant material was antigenic when used in ELISA for Lassa virus-specific antibodies, reacting well with MAbs specific for the nucleocapsid protein and with sera from experimentally infected guinea-pigs. The recombinant ELISA was able to clearly distinguish sera from human cases of Lassa fever against a panel of known negative sera of African origin. Recombinant-infected insect cells were an effective substitute for mammalian cells infected with Lassa virus itself in the immunofluorescence assay for Lassa virus-specific antibodies. This system offers attractive alternatives to the use of Lassa virus-infected materials as reagents in diagnostic procedures.

  6. Zika Virus Infection in Mice Causes Panuveitis with Shedding of Virus in Tears

    Directory of Open Access Journals (Sweden)

    Jonathan J. Miner

    2016-09-01

    Full Text Available Zika virus (ZIKV is an emerging flavivirus that causes congenital abnormalities and Guillain-Barré syndrome. ZIKV infection also results in severe eye disease characterized by optic neuritis, chorioretinal atrophy, and blindness in newborns and conjunctivitis and uveitis in adults. We evaluated ZIKV infection of the eye by using recently developed mouse models of pathogenesis. ZIKV-inoculated mice developed conjunctivitis, panuveitis, and infection of the cornea, iris, optic nerve, and ganglion and bipolar cells in the retina. This phenotype was independent of the entry receptors Axl or Mertk, given that Axl−/−, Mertk−/−, and Axl−/−Mertk−/− double knockout mice sustained levels of infection similar to those of control animals. We also detected abundant viral RNA in tears, suggesting that virus might be secreted from lacrimal glands or shed from the cornea. This model provides a foundation for studying ZIKV-induced ocular disease, defining mechanisms of viral persistence, and developing therapeutic approaches for viral infections of the eye.

  7. Early events associated with infection of Epstein-Barr virus infection of primary B-cells.

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    Sabyasachi Halder

    Full Text Available Epstein Barr virus (EBV is closely associated with the development of a vast number of human cancers. To develop a system for monitoring early cellular and viral events associated with EBV infection a self-recombining BAC containing 172-kb of the Epstein Barr virus genome BAC-EBV designated as MD1 BAC (Chen et al., 2005, J.Virology was used to introduce an expression cassette of green fluorescent protein (GFP by homologous recombination, and the resultant BAC clone, BAC-GFP-EBV was transfected into the HEK 293T epithelial cell line. The resulting recombinant GFP EBV was induced to produce progeny virus by chemical inducer from the stable HEK 293T BAC GFP EBV cell line and the virus was used to immortalize human primary B-cell as monitored by green fluorescence and outgrowth of the primary B cells. The infection, B-cell activation and cell proliferation due to GFP EBV was monitored by the expression of the B-cell surface antigens CD5, CD10, CD19, CD23, CD39, CD40 , CD44 and the intercellular proliferation marker Ki-67 using Flow cytometry. The results show a dramatic increase in Ki-67 which continues to increase by 6-7 days post-infection. Likewise, CD40 signals showed a gradual increase, whereas CD23 signals were increased by 6-12 hours, maximally by 3 days and then decreased. Monitoring the viral gene expression pattern showed an early burst of lytic gene expression. This up-regulation of lytic gene expression prior to latent genes during early infection strongly suggests that EBV infects primary B-cell with an initial burst of lytic gene expression and the resulting progeny virus is competent for infecting new primary B-cells. This process may be critical for establishment of latency prior to cellular transformation. The newly infected primary B-cells can be further analyzed for investigating B cell activation due to EBV infection.

  8. Chemical Modifications of Antisense Morpholino Oligomers Enhance Their Efficacy against Ebola Virus Infection

    Science.gov (United States)

    2009-05-01

    specific PMOs in infected cells and mice during lethal Ebola virus challenge. Members of the Filoviridae family of viruses , Ebola virus (EBOV) and Marburg ...American Society for Microbiology. All Rights Reserved. Chemical Modifications of Antisense Morpholino Oligomers Enhance Their Efficacy against Ebola Virus ...sequence is complementary to a region spanning the start codon of VP24 mRNA were protected against lethal Ebola virus challenge. In the present study, we

  9. Protection against Influenza Virus Infection of Mice Fed Bifidobacterium breve YIT4064

    OpenAIRE

    1999-01-01

    Mice fed Bifidobacterium breve YIT4064 and immunized orally with influenza virus were more strongly protected against influenza virus infection of the lower respiratory tract than ones immunized with influenza virus only. The number of mice with enhanced anti-influenza virus immunoglobulin G (IgG) in serum upon oral administration of B. breve YIT4064 and oral immunization with influenza virus was significantly greater than that upon oral immunization with influenza...

  10. Equine herpes virus 2 infection in horse populations in Poland.

    Science.gov (United States)

    Ruszczyk, A; Cywinska, A; Banbura, M W

    2004-01-01

    The prevalence of Equine herpesvirus 2 (EHV-2) infections in the horse populations in Poland was investigated. Peripheral blood leukocytes (PBLs) of 139 horses were tested. The animals were divided into four groups: clinically healthy horses, horses suffering from respiratory disorders, mares with a recent abortion and horses with diagnosed ataxia. Thirty-four virus isolates were obtained from leukocytes of the tested animals by cocultivation with equine dermal cells and were identified as EHV-2 by PCR using primers for the gB gene of EHV-2 and/or primers for the sequence located upstream of the gene homologous to the equine interleukin 10 (IL-10) gene. These results indicate that EHV-2 is prevalent in horse populations in Poland. As the virus was most frequently isolated from horses with respiratory disorders its etiological importance may be considered.

  11. Interleukin 28B genetic polymorphism and hepatitis B virus infection.

    Science.gov (United States)

    Takahashi, Toru

    2014-09-14

    Interleukin (IL) 28B genetic polymorphism is significantly associated with the sustained virological response rate in patients with chronic hepatitis C treated with pegylated interferon-α (PEG-IFN) plus ribavirin and with spontaneous hepatitis C virus clearance. However, a consensus on the relationship between IL28B genetic polymorphism and the favorable outcome of chronic hepatitis B virus infection defined by hepatitis B e antigen seroconversion, and/or hepatitis B surface antigen seroclearance in patients treated with interferon or PEG-IFN has not been reached. Several reports failed to show a positive association, while some studies demonstrated a positive association in certain subject settings. More prospective studies including large cohorts are needed to determine the possible association between IL28B genetic polymorphism and the outcome of interferon or PEG-IFN treatment for chronic hepatitis B.

  12. Systems biology unravels interferon responses to respiratory virus infections

    Institute of Scientific and Technical Information of China (English)

    Andrea; L; Kroeker; Kevin; M; Coombs

    2014-01-01

    Interferon production is an important defence against viral replication and its activation is an attractive therapeutic target. However, it has long been known that viruses perpetually evolve a multitude of strategies to evade these host immune responses. In recent years there has been an explosion of information on virusinduced alterations of the host immune response that have resulted from data-rich omics technologies. Unravelling how these systems interact and determining the overall outcome of the host response to viral infection will play an important role in future treatment and vaccine development. In this review we focus primarily on the interferon pathway and its regulation as well as mechanisms by which respiratory RNA viruses interfere with its signalling capacity.

  13. Fungal DNA virus infects a mycophagous insect and utilizes it as a transmission vector

    Science.gov (United States)

    Liu, Si; Xie, Jiatao; Cheng, Jiasen; Li, Bo; Chen, Tao; Fu, Yanping; Li, Guoqing; Wang, Manqun; Jin, Huanan; Wan, Hu; Jiang, Daohong

    2016-01-01

    Mycoviruses are usually transmitted horizontally via hyphal anastomosis and vertically via sexual/asexual spores. Previously, we reported that a gemycircularvirus, Sclerotinia sclerotiorum hypovirulence-associated DNA virus 1 (SsHADV-1), could infect its fungal host extracellularly. Here, we discovered that SsHADV-1 could infect a mycophagous insect, Lycoriella ingenua, and use it as a transmission vector. Virus acquired by larvae feeding on colonies of a virus-infected strain of S. sclerotiorum was replicated and retained in larvae, pupae, adults, and eggs. Virus could be transmitted to insect offspring when larvae were injected with virus particles and allowed to feed on a nonhost fungus. Virus replication in insect cells was further confirmed by inoculating Spodoptera frugiperda cells with virus particles and analyzing with RT-PCR, Northern blot, immunofluorescence, and flow cytometry assays. Larvae could transmit virus once they acquired virus by feeding on virus-infected fungal colony. Offspring larvae hatched from viruliferous eggs were virus carriers and could also successfully transmit virus. Virus transmission between insect and fungus also occurred on rapeseed plants. Virus-infected isolates produced less repellent volatile substances to attract adults of L. ingenua. Furthermore, L. ingenua was easily observed on Sclerotinia lesions in rapeseed fields, and viruliferous adults were captured from fields either sprayed with a virus-infected fungal strain or nonsprayed. Our findings may facilitate the exploration of mycoviruses for control of fungal diseases and enhance our understanding of the ecology of SsHADV-1 and other newly emerging SsHADV-1–like viruses, which were recently found to be widespread in various niches including human HIV-infected blood, human and animal feces, insects, plants, and even sewage. PMID:27791095

  14. Additive interactions of unrelated viruses in mixed infections of cowpea (Vigna unguiculata L. Walp).

    Science.gov (United States)

    Nsa, Imade Y; Kareem, Kehinde T

    2015-01-01

    This study was carried out to determine the effects of single infections and co-infections of three unrelated viruses on three cowpea cultivars (one commercial cowpea cultivar "White" and 2 IITA lines; IT81D-985 and TVu 76). The plants were inoculated with Cowpea aphid-borne mosaic virus (CABMV), genus Potyvirus, Cowpea mottle virus (CMeV), genus Carmovirus and Southern bean mosaic virus (SBMV), genus Sobemovirus singly and in mixture (double and triple) at 10, 20, and 30 days after planting (DAP). The treated plants were assessed for susceptibility to the viruses, growth, and yield. In all cases of infection, early inoculation resulted in higher disease severity compared with late infection. The virus treated cowpea plants were relatively shorter than buffer inoculated control plants except the IT81D-985 plants that were taller and produced more foliage. Single infections by CABMV, CMeV, and SBMV led to a complete loss of seeds in the three cowpea cultivars at 10 DAP; only cultivar White produced some seeds at 30 DAP. Double and triple virus infections led to a total loss of seeds in all three cowpea cultivars. None of the virus infected IITA lines produced any seeds except IT81D-985 plants co-infected with CABMV and SBMV at 30 DAP with a reduction of 80%. Overall, the commercial cultivar "White" was the least susceptible to the virus treatments and produced the most yield (flowers, pods, and seeds). CABMV was the most aggressive of these viruses and early single inoculations with this virus resulted in the premature death of some of the seedlings. The presence of the Potyvirus, CABMV in the double virus infections did not appear to increase disease severity or yield loss. There was no strong evidence for synergistic interactions between the viruses in the double virus mixtures.

  15. The Innate Immune Playbook for Restricting West Nile Virus Infection

    Directory of Open Access Journals (Sweden)

    Kendra M. Quicke

    2013-10-01

    Full Text Available West Nile virus (WNV is an emerging mosquito-borne flavivirus that causes annual epidemics of encephalitic disease throughout the world. Despite the ongoing risk to public health, no approved vaccines or therapies exist for use in humans to prevent or combat WNV infection. The innate immune response is critical for controlling WNV replication, limiting virus-induced pathology, and programming protective humoral and cell-mediated immunity to WNV infection. The RIG-I like receptors, Toll-like receptors, and Nod-like receptors detect and respond to WNV by inducing a potent antiviral defense program, characterized by production of type I IFN, IL-1β and expression of antiviral effector genes. Recent research efforts have focused on uncovering the mechanisms of innate immune sensing, antiviral effector genes that inhibit WNV, and countermeasures employed by WNV to antagonize innate immune cellular defenses. In this review, we highlight the major research findings pertaining to innate immune regulation of WNV infection.

  16. A Susceptible Mouse Model for Zika Virus Infection.

    Science.gov (United States)

    Dowall, Stuart D; Graham, Victoria A; Rayner, Emma; Atkinson, Barry; Hall, Graham; Watson, Robert J; Bosworth, Andrew; Bonney, Laura C; Kitchen, Samantha; Hewson, Roger

    2016-05-01

    Zika virus (ZIKV) is a mosquito-borne pathogen which has recently spread beyond Africa and into Pacific and South American regions. Despite first being detected in 1947, very little information is known about the virus, and its spread has been associated with increases in Guillain-Barre syndrome and microcephaly. There are currently no known vaccines or antivirals against ZIKV infection. Progress in assessing interventions will require the development of animal models to test efficacies; however, there are only limited reports on in vivo studies. The only susceptible murine models have involved intracerebral inoculations or juvenile animals, which do not replicate natural infection. Our report has studied the effect of ZIKV infection in type-I interferon receptor deficient (A129) mice and the parent strain (129Sv/Ev) after subcutaneous challenge in the lower leg to mimic a mosquito bite. A129 mice developed severe symptoms with widespread viral RNA detection in the blood, brain, spleen, liver and ovaries. Histological changes were also striking in these animals. 129Sv/Ev mice developed no clinical symptoms or histological changes, despite viral RNA being detectable in the blood, spleen and ovaries, albeit at lower levels than those seen in A129 mice. Our results identify A129 mice as being highly susceptible to ZIKV and thus A129 mice represent a suitable, and urgently required, small animal model for the testing of vaccines and antivirals.

  17. Gastrointestinal opportunistic infections in human immunodeficiency virus disease

    Directory of Open Access Journals (Sweden)

    Al Anazi Awadh

    2009-01-01

    Full Text Available Gastrointestinal (GI opportunistic infections (OIs are commonly encountered at various stages of human immunodeficiency virus (HIV disease. In view of the suppressive nature of the virus and the direct contact with the environment, the GI tract is readily accessible and is a common site for clinical expression of HIV. The subject is presented based on information obtained by electronic searches of peer-reviewed articles in medical journals, Cochrane reviews and PubMed sources. The spectrum of GI OIs ranges from oral lesions of Candidiasis, various lesions of viral infections, hepatobiliary lesions, pancreatitis and anorectal lesions. The manifestations of the disease depend on the level of immunosuppression, as determined by the CD4 counts. The advent of highly active antiretroviral therapy has altered the pattern of presentation, resorting mainly to features of antimicrobial-associated colitis and side effects of antiretroviral drugs. The diagnosis of GI OIs in HIV/ acquired immunodeficiency syndrome patients is usually straightforward. However, subtle presentations require that the physicians should have a high index of suspicion when given the setting of HIV infection.

  18. A Susceptible Mouse Model for Zika Virus Infection.

    Directory of Open Access Journals (Sweden)

    Stuart D Dowall

    2016-05-01

    Full Text Available Zika virus (ZIKV is a mosquito-borne pathogen which has recently spread beyond Africa and into Pacific and South American regions. Despite first being detected in 1947, very little information is known about the virus, and its spread has been associated with increases in Guillain-Barre syndrome and microcephaly. There are currently no known vaccines or antivirals against ZIKV infection. Progress in assessing interventions will require the development of animal models to test efficacies; however, there are only limited reports on in vivo studies. The only susceptible murine models have involved intracerebral inoculations or juvenile animals, which do not replicate natural infection. Our report has studied the effect of ZIKV infection in type-I interferon receptor deficient (A129 mice and the parent strain (129Sv/Ev after subcutaneous challenge in the lower leg to mimic a mosquito bite. A129 mice developed severe symptoms with widespread viral RNA detection in the blood, brain, spleen, liver and ovaries. Histological changes were also striking in these animals. 129Sv/Ev mice developed no clinical symptoms or histological changes, despite viral RNA being detectable in the blood, spleen and ovaries, albeit at lower levels than those seen in A129 mice. Our results identify A129 mice as being highly susceptible to ZIKV and thus A129 mice represent a suitable, and urgently required, small animal model for the testing of vaccines and antivirals.

  19. Epidemiological changes of respiratory syncytial virus (RSV infections in Israel.

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    Shira Hirsh

    Full Text Available RSV is the leading cause of lower respiratory-tract infections in infants and therefore demands in-depth epidemiological characterization. We investigated here the distribution of RSV types in Israel between the years 2005-2012. Clinical samples were collected from 11,018 patients hospitalized due to respiratory illnesses and were evaluated for the presence of various respiratory viruses, including RSV A and RSV B. Until 2008, each year was characterized by the presence of one dominant type of RSV. However, from 2008, both RSV A and B types were detected at significant levels, particularly among infants aged 0-2 years. Furthermore, significant changes in the RSV A and RSV B subtypes circulating in Israel since 2008 were observed. Finally, we demonstrate that, irrespectively of the changes observed in RSV epidemiology, when the pandemic H1N1pdm09 influenza virus appeared in 2009, RSV infections were delayed and were detected when infection with H1N1pdm09 had declined.

  20. Congenital guinea pig infection with attenuated Junin virus strains.

    Science.gov (United States)

    Boxaca, M C; Gómez, M M; Malumbres, E; de Guerrero, L B

    1985-01-01

    Guinea pigs born from mothers infected before or during pregnancy with 10(3) PFU of the attenuated XJC13 or XJ0 strains of Junin virus (JV) by the intramuscular route showed 31.5% mortality that was not attributable to the mothers' clinical condition or to lack of care. There was a slight drop in mortality rate when the mothers were infected at the beginning or end of their gestation period. JV isolation from the 9 offspring killed from 1 to 125 days of age proved that virus transmitted transplacentally or soon after birth was able to persist, although titers were not higher than 10(2.7) PFU/g of tissue in various organs, including brain. Cell-associated viremia could thus account for viral spread after birth. Since an active humoral response was detected in the same animals, although Nt antibody titers were below 1:16, a state of tolerance did not exist in these congenitally infected animals. The carrier state appeared to modify guinea pig susceptibility to JV; after challenge with the pathogenic XJ strain of JV, 2 animals survived and developed normal humoral responses, while half of the remaining animals did not show typical signs of Argentine hemorrhagic fever. Although JV persistence appeared to cause no deleterious effects in surviving guinea pigs, its long-term risk remains to be determined.